Topical Collection "Feature Innovation Papers"

Editor

Prof. Dr. Chien-Hung Liu
E-Mail Website
Collection Editor
Department of Mechanical Engineering, National Chung Hsing University, 250 Kuo Kuang Rd., Taichung 402, Taiwan
Interests: high precision instrument design; laser engineering; smart sensors and actuators; optical device; optical measurement; metrology
Special Issues, Collections and Topics in MDPI journals

Topical Collection Information

Dear Colleagues,

This is a collection of top quality papers from the editorial board members, or those who have been invited by the editorial office and the Editor-in-Chief. The topics include:

  • New innovation ideas
  • New innovation technologies
  • New innovation products

The papers should be research papers (or review papers) with the detailed description and verification of the author’s own work.

Prof. Dr. Chien-Hung Liu
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the collection website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Inventions is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1500 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • innovation idea
  • innovation technology
  • innovation product

Published Papers (71 papers)

2023

Jump to: 2022, 2021, 2020, 2018, 2017, 2016

Article
A 2-DoF Kinematic Chain Analysis of a Magnetic Spring Excited by Vibration Generator Based on a Neural Network Design for Energy Harvesting Applications
Inventions 2023, 8(1), 34; https://doi.org/10.3390/inventions8010034 - 30 Jan 2023
Viewed by 221
Abstract
In this paper, an original mathematical model and experimental results for the vibration generator and the magnetic spring prototype that converts mechanical energy to electrical energy are proposed. The magnetic spring model is developed by a robotic approach based on Denavit–Hartenberg’s notation and [...] Read more.
In this paper, an original mathematical model and experimental results for the vibration generator and the magnetic spring prototype that converts mechanical energy to electrical energy are proposed. The magnetic spring model is developed by a robotic approach based on Denavit–Hartenberg’s notation and designed by the 2-degrees of freedom kinematic chain for determination of its motion and estimation of several resonance frequencies useful in many energy harvesting applications. The vibration generator that moves the magnetic spring is modeled by neural networks and the magnetic spring potential energy is calculated by the finite elements method (FEM). Furthermore, the magnetic spring and the vibration generator are designed by the Simulink block diagram. Testing results of the magnetic spring and vibration generator displacement conducted in laboratory have shown good agreement with simulation results. Full article
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Article
A Generalized Framework for Adopting Regression-Based Predictive Modeling in Manufacturing Environments
Inventions 2023, 8(1), 32; https://doi.org/10.3390/inventions8010032 - 29 Jan 2023
Viewed by 179
Abstract
In this paper, the growing significance of data analysis in manufacturing environments is exemplified through a review of relevant literature and a generic framework to aid the ease of adoption of regression-based supervised learning in manufacturing environments. To validate the practicality of the [...] Read more.
In this paper, the growing significance of data analysis in manufacturing environments is exemplified through a review of relevant literature and a generic framework to aid the ease of adoption of regression-based supervised learning in manufacturing environments. To validate the practicality of the framework, several regression learning techniques are applied to an open-source multi-stage continuous-flow manufacturing process data set to typify inference-driven decision-making that informs the selection of regression learning methods for adoption in real-world manufacturing environments. The investigated regression learning techniques are evaluated in terms of their training time, prediction speed, predictive accuracy (R-squared value), and mean squared error. In terms of training time (TT), k-NN20 (k-Nearest Neighbour with 20 neighbors) ranks first with average and median values of 4.8 ms and 4.9 ms, and 4.2 ms and 4.3 ms, respectively, for the first stage and second stage of the predictive modeling of the multi-stage continuous-flow manufacturing process, respectively, over 50 independent runs. In terms of prediction speed (PS), DTR (decision tree regressor) ranks first with average and median values of 5.6784×106 observations per second (ob/s) and 4.8691×106 observations per second (ob/s), and 4.9929×106 observations per second (ob/s) and 5.8806×106 observations per second (ob/s), respectively, for the first stage and second stage of the predictive modeling of the multi-stage continuous-flow manufacturing process, respectively, over 50 independent runs. In terms of R-squared value (R2), BR (bagging regressor) ranks first with average and median values of 0.728 and 0.728, respectively, over 50 independent runs, for the first stage of the predictive modeling of the multi-stage continuous-flow manufacturing process, and RFR (random forest regressor) ranks first with average and median values of 0.746 and 0.746, respectively, over 50 independent runs, for the second stage of the predictive modeling of the multi-stage continuous-flow manufacturing process. In terms of mean squared error (MSE), BR (bagging regressor) ranks first with average and median values of 2.7 and 2.7, respectively, over 50 independent runs, for the first stage of the predictive modeling of the multi-stage continuous-flow manufacturing process, and RFR (random forest regressor) ranks first with average and median values of 3.5 and 3.5, respectively, over 50 independent runs, for the second stage of the predictive modeling of the multi-stage continuous-flow manufacturing process. All methods are further ranked inferentially using the statistics of their performance metrics to identify the best method(s) for the first and second stages of the predictive modeling of the multi-stage continuous-flow manufacturing process. A Wilcoxon rank sum test is then used to statistically verify the inference-based rankings. DTR and k-NN20 have been identified as the most suitable regression learning techniques given the multi-stage continuous-flow manufacturing process data used for experimentation. Full article
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Communication
An Automatic Question Generator for Chinese Comprehension
Inventions 2023, 8(1), 31; https://doi.org/10.3390/inventions8010031 - 28 Jan 2023
Viewed by 159
Abstract
Question generation (QG) is a natural language processing (NLP) problem that aims to generate natural questions from a given sentence or paragraph. QG has many applications, especially in education. For example, QG can complement teachers’ efforts in creating assessment materials by automatically generating [...] Read more.
Question generation (QG) is a natural language processing (NLP) problem that aims to generate natural questions from a given sentence or paragraph. QG has many applications, especially in education. For example, QG can complement teachers’ efforts in creating assessment materials by automatically generating many related questions. QG can also be used to generate frequently asked question (FAQ) sets for business. Question answering (QA) can benefit from QG, where the training dataset of QA can be enriched using QG to improve the learning and performance of QA algorithms. However, most of the existing works and tools in QG are designed for English text. This paper presents the design of a web-based question generator for Chinese comprehension. The generator provides a user-friendly web interface for users to generate a set of wh-questions (i.e., what, who, when, where, why, and how) based on a Chinese text conditioned on a corresponding set of answer phrases. The web interface allows users to easily refine the answer phrases that are automatically generated by the web generator. The underlying question generation is based on the transformer approach, which was trained on a dataset combined from three publicly available Chinese reading comprehension datasets, namely, DRUD, CMRC2017, and CMRC2018. Linguistic features such as parts of speech (POS) and named-entity recognition (NER) are extracted from the text, which together with the original text and the answer phrases, are then fed into a machine learning algorithm based on a pre-trained mT5 model. The generated questions with answers are displayed in a user-friendly format, supplemented with the source sentences in the text used for generating each question. We expect the design of this web tool to provide insight into how Chinese question generation can be made easily accessible to users with low computer literacy. Full article
Article
Reverse Engineering of a Racing Motorbike Connecting Rod
Inventions 2023, 8(1), 23; https://doi.org/10.3390/inventions8010023 - 16 Jan 2023
Viewed by 359
Abstract
The following scientific paper aims to analyze in detail the methodology for reverse engineering of a racing motorcycle connecting rod. The objective is to start with a product available on the market as a spare part, reconstruct its CAD model with a high [...] Read more.
The following scientific paper aims to analyze in detail the methodology for reverse engineering of a racing motorcycle connecting rod. The objective is to start with a product available on the market as a spare part, reconstruct its CAD model with a high standard of accuracy, then proceed with lightening modifications to arrive at a new, improved design. The innovative aspect of the procedure lies in the fact that in order to ensure accuracy on the order of a tenth of a millimeter during reconstruction, it was decided to use a FARO articulated arm laser to scan the component’s outer surface. By taking advantage of appropriate redesign CAD software (Geomagic Design X), a reconstruction can proceed within the high standard of accuracy imposed. In conclusion, the modifications made through material removal allow an improvement in product efficiency, ensuring high performance. Full article
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Article
Mechanical Chaotic Duffing System with Magnetic Springs
Inventions 2023, 8(1), 19; https://doi.org/10.3390/inventions8010019 - 11 Jan 2023
Viewed by 418
Abstract
Mechanical systems with inherent chaotic behavior are of notable practical interest due to their applicability in many fields of technology, from industrial mills and concrete mixers to microscopic micromechanical random bit generators. One of the most generic mathematical models for designing chaotic mechanical [...] Read more.
Mechanical systems with inherent chaotic behavior are of notable practical interest due to their applicability in many fields of technology, from industrial mills and concrete mixers to microscopic micromechanical random bit generators. One of the most generic mathematical models for designing chaotic mechanical systems is the Duffing oscillator, which demonstrates chaotic motion under periodic excitation. The mechanical implementation of Duffing oscillator requires nonlinear springs, which can be implemented using different physical principles. In the current study, we propose the mechanical Duffing oscillator with magnetic springs as a low-wear, robust and easy-to-implement solution. We show by simulation and experimentation that the developed mechanical system performs chaotic oscillations in a wide range of parameters. The proposed design can be revised in a problem-specific manner and achieve many practical applications. Full article
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Article
Information Protection in Complexes with Unmanned Aerial Vehicles Using Moving Target Technology
Inventions 2023, 8(1), 18; https://doi.org/10.3390/inventions8010018 - 11 Jan 2023
Viewed by 514
Abstract
This article is devoted to the problem of information security in complexes with unmanned aerial vehicles (UAV). Science knows a new promising method of information protection: moving target defense (MTD). The essence of this method is that due to periodic changes in the [...] Read more.
This article is devoted to the problem of information security in complexes with unmanned aerial vehicles (UAV). Science knows a new promising method of information protection: moving target defense (MTD). The essence of this method is that due to periodic changes in the parameters of the infocommunication network the information about the information infrastructure collected by the attacker at the reconnaissance stage becomes irrelevant, and the attack becomes ineffective. This article also discusses the features and types of confidential information processed in complexes with UAV and provides a review of the experience of creating systems for protecting information from unauthorized access of complexes with UAV. The proposed hypothesis is tested using a model created using a tool: the GNS3 program. The model in the form of a test network in the GNS3 emulator recreates the proposed method. It was concluded that the effectiveness of the harmful impact on the complex with UAV was reduced by three times. The disadvantages of the proposed method include the problem of ensuring the availability of protected information resources for other legitimate, authorized participants in network interaction, as well as the need to solve the problem of choosing the optimal frequency of changing parameters. Full article
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Article
Equivalent Exchange Method for Decision-Making in Case of Alternatives with Incomparable Attributes
Inventions 2023, 8(1), 12; https://doi.org/10.3390/inventions8010012 - 06 Jan 2023
Viewed by 373
Abstract
The paper is focused on searching for novel methods aimed at improving the performance and usability of a common decision-making process where a panel of experts are assisted by specialized software systems. An equivalent exchange method (EEM) is considered in the paper as [...] Read more.
The paper is focused on searching for novel methods aimed at improving the performance and usability of a common decision-making process where a panel of experts are assisted by specialized software systems. An equivalent exchange method (EEM) is considered in the paper as a potential candidate for a versatile method applicable in expert decision-making process for solving problems in various subject domains. The method is formally described in the paper in the form of an iterative algorithm where each iteration leads to the reduce in the number of alternatives under consideration until it converges to the preferable one. The key feature of EEM consists in the fact that the original comparison between multiple alternatives described by many attributes measured in different units is replaced by the sequence of simple exchanges between pairs of alternatives where only two attributes are engaged at once. The numerical example illustrating the full run of the algorithm is thoroughly described, so the actions performed in the steps of the algorithm are explained. The case of the successful implementation of EEM as the module of Expert Decision Support System is also presented. Full article
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2022

Jump to: 2023, 2021, 2020, 2018, 2017, 2016

Article
Execution Time Decrease for Controllers Based on Adaptive Particle Swarm Optimization
Inventions 2023, 8(1), 9; https://doi.org/10.3390/inventions8010009 - 30 Dec 2022
Viewed by 605
Abstract
Execution time is an important topic when using metaheuristic-based optimization algorithms within control structures. This is the case with Receding Horizon Control, whose controller makes predictions based on a metaheuristic algorithm. Because the closed loop’s main time constraint is that the controller’s run [...] Read more.
Execution time is an important topic when using metaheuristic-based optimization algorithms within control structures. This is the case with Receding Horizon Control, whose controller makes predictions based on a metaheuristic algorithm. Because the closed loop’s main time constraint is that the controller’s run time must be smaller than the sampling period, this paper joins the authors’ previous work in investigating decreasing execution time. In this context, good results have been obtained by introducing the “reference control profile” concept that leads to the idea of adapting the control variables’ domains for each sampling period. This paper continues to address this concept, which is adjusted to harmonize with the Particle Swarm Optimization algorithm. Moreover, besides adapting the control variables’ domains, the proposed controller’s algorithm tunes these domains to avoid losing convergence. A simulation study validates the new techniques using a nontrivial process model and considering three modes in which the controller works. The results showed that the proposed techniques have practical relevance and significantly decrease execution time. Full article
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Article
Robust Hierarchical Control Design for the Power Sharing in Hybrid Shipboard Microgrids
Inventions 2023, 8(1), 7; https://doi.org/10.3390/inventions8010007 - 29 Dec 2022
Viewed by 825
Abstract
Hybrid microgrid optimization, integration, and control are becoming increasingly important. Renewable energy source integrations are being used more often in shipping ports, as well as on short-distance cruises and ferries. Several seaports presently lack cold ironing services, which are shore-based power stations that [...] Read more.
Hybrid microgrid optimization, integration, and control are becoming increasingly important. Renewable energy source integrations are being used more often in shipping ports, as well as on short-distance cruises and ferries. Several seaports presently lack cold ironing services, which are shore-based power stations that provide electricity to ships from the main utility grids. Furthermore, diesel engines and diesel generator-based shipboards must be continuously running and on-line when docking to provide additional loads of ships due to the absence of cold-ironing services at many ports. In this research, we analytically presented the robustness of our proposed hierarchical control design for the hybrid shipboard Microgrid system containing multiple DGs and renewable energy resource (RES) integrations. The performance comparison of the conventional proportional integral (PI) vs. Sliding Mode Controller (SMC)-based control design is validated with simulation tests under different static and dynamical load conditions for both AC and DC types of loads. We further considered multi-DGs and RES integrations into our system to validate our design’s robustness against noise and unwanted faulty load conditions. The complete system stability analysis and designing of the control law are performed. Mathematical derivations and simulation results prove the robustness of the proposed hierarchical control architecture and compare the performance characteristics of two secondary controllers designed using a MATLAB/Simulink environment. Full article
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Article
D2D Communication Underlaying UAV-Enabled Network: A Content-Sharing Perspective
Inventions 2023, 8(1), 5; https://doi.org/10.3390/inventions8010005 - 26 Dec 2022
Viewed by 474
Abstract
The last era has witnessed an unprecedented demand for digital content. To meet these rigorous demands, researchers have been busy developing content-sharing applications and services. The advancement in technology has aided this process. Unmanned aerial vehicles (UAVs) have gained a lot of attention [...] Read more.
The last era has witnessed an unprecedented demand for digital content. To meet these rigorous demands, researchers have been busy developing content-sharing applications and services. The advancement in technology has aided this process. Unmanned aerial vehicles (UAVs) have gained a lot of attention in assisting cellular networks since they play a paramount role in disaster management, capacity enhancement, on-demand communication, and content dissemination. In this study, we consider content-centric UAV communication underlaid device-to-device (D2D) users. Different from the current research trends, this study considers clustering the D2D users (i.e., ground users) and UAV only deliver the requested content to the cluster heads. We considered the clustering approach since the UAV is an energy constraint device and the aim is to reduce the energy consumed by the UAV during the communication phase. Clustering the ground nodes will allow the UAV to communicate to only cluster heads as compared with a bigger group of users. Cluster heads are then responsible to forward the cached contents to their respective cluster members. A comprehensive performance evaluation of the proposed scheme was conducted by benchmarking it against state-of-the-art research works and considering various performance parameters such as throughput, energy consumption, and content delivery delay. The proposed scheme produced promising results for all parameters and against other research works as well. Full article
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Article
QFD and SDE Methods Applied to Autonomous Minibus Redesign and an Innovative Mobile Charging System (MBS)
Inventions 2023, 8(1), 1; https://doi.org/10.3390/inventions8010001 - 21 Dec 2022
Viewed by 443
Abstract
Urban mobility scenarios are constantly evolving, and today’s solutions may not be adequate in the future. Through innovative analysis and design methods encapsulated by the IDeS methodology, it is possible to plausibly hypothesize a number of key scenarios to be analyzed, for which [...] Read more.
Urban mobility scenarios are constantly evolving, and today’s solutions may not be adequate in the future. Through innovative analysis and design methods encapsulated by the IDeS methodology, it is possible to plausibly hypothesize a number of key scenarios to be analyzed, for which vehicles can be designed in order to solve the main problems. Scenarios such as the steady growth in public mobility, based on the sharing of electric mini-buses at the expense of the privatization of the means of transport, lead to the gradual rethinking of citizens’ needs and the supporting infrastructure. Problems such as the lack of privacy of public vehicles, the efficiency of the infrastructure and recharging modes of e-buses, and autonomous driving are addressed here through methods such as QFD (quality function deployment) and SDE (stylistic design engineering), with the aim of outlining a proposal that, to date, is futuristic but is designed to be concrete and feasible within the next decade. These methodologies were applied to the design of a sustainable urban transport system consisting of an electric mini-bus, effected by rethinking the layout of the interior spaces in favor of areas enabling greater privacy and a mobile recharging system (MBS) capable of offering a new management strategy for the non-stop recharging phase. Through the use of an MBS, which functions as a mobile ‘energy bank’ module that is capable of autonomously reaching a mini-bus in need of recharging and extending its autonomy by connecting and recharging it, the proposed system can potentially be enabled to perform its required service during the day without any need to spend time making intermediate stops for the purpose of recharging. Full article
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Article
Design and 3D Manufacturing of an Improved Heliostatic Illuminator
Inventions 2022, 7(4), 127; https://doi.org/10.3390/inventions7040127 - 19 Dec 2022
Viewed by 598
Abstract
Increasing daylighting levels contributes to improving the energy efficiency of buildings and consequently to the fight against climate change. This work presents a new illuminator based on a previous single-axis polar heliostat. This heliostat allows redirecting sunlight to a specific space to be [...] Read more.
Increasing daylighting levels contributes to improving the energy efficiency of buildings and consequently to the fight against climate change. This work presents a new illuminator based on a previous single-axis polar heliostat. This heliostat allows redirecting sunlight to a specific space to be illuminated at any time of the day. The system presented is simple but compact in size. It has been manufactured by 3D printing with recyclable PETG plastics. Three-dimensional printing has allowed reduction of the mass of the system to less than 5 kg, which means high stability and manageability. Moreover, the system has been provided with an assembly structure that facilitates its correct installation by a single operator. The result is a heliostatic illuminator with an average pointing error of 10 mrad, an acceptable error for urban applications. Finally, a low-cost and high-replicability device has been achieved, which makes it an easily reproducible illuminator and favors its extensive installation. Full article
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Article
Method of the Mechanical Properties Evaluation of Polyethylene Gas Pipelines with Portable Hardness Testers
Inventions 2022, 7(4), 125; https://doi.org/10.3390/inventions7040125 - 13 Dec 2022
Viewed by 503
Abstract
This article is devoted to the study of means and methods for non-destructive testing mechanical properties of polyethylene gas pipelines that have been in operation for 25–55 years. In order to assess mechanical properties, stress at yield was chosen as a key parameter. [...] Read more.
This article is devoted to the study of means and methods for non-destructive testing mechanical properties of polyethylene gas pipelines that have been in operation for 25–55 years. In order to assess mechanical properties, stress at yield was chosen as a key parameter. Stress at yield is determined from the results of tensile tests and is associated with the limiting circumferential (hoop) stress, determined from the results of tests for short-term pressure. Tensile tests require sample cutting and the shutdown of pipelines’ service. To solve this problem of nondestructive testing of pipelines, tests were carried out using the methods of Shore, Leeb and dynamic instrumental indentation. According to the test results, it was revealed that the correlation coefficient between the values of stress at yield and hardness, obtained by the method of dynamic instrumental indentation, is 0.98 which confirms the possibility of the evaluation of the mechanical properties of pipelines by the method of dynamic instrumental indentation. Full article
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Article
A New Mechanism of Male Plug for Electrical Protection
Inventions 2022, 7(4), 123; https://doi.org/10.3390/inventions7040123 - 13 Dec 2022
Viewed by 516
Abstract
There are many inventions to avoid the risk of electric contact in the plug. However, the objective of the invention resulting from the research is the proposal of a complementary measure to the existing ones, solving the specific problem of electrocutions that occur [...] Read more.
There are many inventions to avoid the risk of electric contact in the plug. However, the objective of the invention resulting from the research is the proposal of a complementary measure to the existing ones, solving the specific problem of electrocutions that occur in the action of connection and disconnection, due to the contact of the user with the active parts of the plug. The research has focused on the proposal of a design solution that solves the problem of electrocution in these particular and common cases. The objective of this article is the disclosure of a male plug protection mechanism, which has been carried out solely with the use of mechanical methods. Its importance lies in the simplicity and feasibility of the registered utility model as well as in the importance that its implementation may entail for the prevention of serious accidents in the electrical field for domestic and industrial use. The work shows the mechanism and operation of the invention of the proposed male plug in terms of protection against electrical hazards. Full article
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Article
Study of the Effect of External Magnetic Fields on the Parameters of the Electrical Communications Probing System for a Microtunneling Shield
Inventions 2022, 7(4), 121; https://doi.org/10.3390/inventions7040121 - 12 Dec 2022
Viewed by 453
Abstract
The issues were reviewed in assessing external electromagnetic fields’ effect on the parameters of an electrical power line probing system based on three-component ferroprobes for detecting active underground power cable lines during microtunnel construction using the thrust boring method (by tunneling shield) in [...] Read more.
The issues were reviewed in assessing external electromagnetic fields’ effect on the parameters of an electrical power line probing system based on three-component ferroprobes for detecting active underground power cable lines during microtunnel construction using the thrust boring method (by tunneling shield) in densely populated urban areas. A study was conducted on the change in the topology of the energized cable magnetic field located in the external magnetic field area created by operating electrical equipment under the influence of an external electromagnetic field and a tunneling shield with installed magneto-sensitive detectors. Experimental studies of the probing system were made. Options have been proposed for compensating the inductance component of the external magnetic field during tunnel driving in urban development and industrial area conditions. Full article
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Article
Decrease in the Starting Temperature of the Reaction for Fabricating Carbides of Refractory Metals When Using Carbon Nanoparticles as Precursors
Inventions 2022, 7(4), 120; https://doi.org/10.3390/inventions7040120 - 12 Dec 2022
Viewed by 622
Abstract
Metal matrix composites with a matrix of refractory metals (niobium, tungsten) and reinforcing nanodiamond particles were prepared for studying the possibility of decreasing the starting temperature of carbide synthesis. The size of primary nanodiamond particles was 4–6 nm, but they were combined in [...] Read more.
Metal matrix composites with a matrix of refractory metals (niobium, tungsten) and reinforcing nanodiamond particles were prepared for studying the possibility of decreasing the starting temperature of carbide synthesis. The size of primary nanodiamond particles was 4–6 nm, but they were combined in large-sized agglomerates. Mechanical alloying was used for producing the composites by crushing agglomerates and distributing nanodiamonds evenly in the metal matrix. The initial and fabricated materials were investigated by X-ray diffraction, differential scanning calorimetry, and transmission and scanning electron microscopy. Thermal processing leads to the reaction for carbide synthesis. Studies have found that the usage of carbon nanoparticles (nanodiamonds) as precursors for fabricating carbides of refractory metals leads to a dramatic decrease in the synthesis temperature in comparison with macro-precursors: lower than 200 °C for tungsten and lower than 350 °C for niobium. Full article
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Article
Analysis of Thermo-Hygrometric Conditions of an Innovative Underwater Greenhouse
Inventions 2022, 7(4), 118; https://doi.org/10.3390/inventions7040118 - 07 Dec 2022
Viewed by 344
Abstract
Nemo’s Garden® Project aims at creating a green, alternative, and original agriculture system based on underwater greenhouses (biospheres) developed for areas where plant growth is difficult in the terrestrial environment due to climate conditions and new global warming issues. Experiments were designed [...] Read more.
Nemo’s Garden® Project aims at creating a green, alternative, and original agriculture system based on underwater greenhouses (biospheres) developed for areas where plant growth is difficult in the terrestrial environment due to climate conditions and new global warming issues. Experiments were designed and performed to measure the thermal and hygrometric behaviour inside the biosphere; a simple theoretical model was developed to analyse the temperature and humidity of the air inside the biosphere in dynamic conditions and to interpret the experimental observations. The main findings of this research were: (i) the photosynthetically active radiation measured inside the underwater biosphere was 25–30% of that at sea level, (ii) the air temperature and relative humidity inside the biosphere showed cyclic daily variations that permitted a water evaporation/vapour condensation process, allowing the self-production of water for plant irrigation, and (iii) the results given by the lumped-parameter theoretical model were in a good agreement with the experiments. Full article
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Article
The Extraction Method of Navigation Line for Cuttage and Film Covering Multi-Functional Machine for Low Tunnels
Inventions 2022, 7(4), 113; https://doi.org/10.3390/inventions7040113 - 02 Dec 2022
Viewed by 1577
Abstract
Aiming at the problem of low intelligence in the automatic navigation of the cuttage and film covering multi-functional machine for low tunnels, this study proposed a navigation line extraction method based on the improved YOLOv5s model, which can achieve the accurate extraction of [...] Read more.
Aiming at the problem of low intelligence in the automatic navigation of the cuttage and film covering multi-functional machine for low tunnels, this study proposed a navigation line extraction method based on the improved YOLOv5s model, which can achieve the accurate extraction of navigation lines based on two planting methods of seedling transplanting and direct seeding. Firstly, we pre-processed the acquired images using inverse perspective transformation. Next, the Coordinate Attention and Ghost modules were applied to improve the YOLOv5s architecture, increasing the detection accuracy and speed of field targets. Finally, we extracted the feature points and fit the navigation lines based on the shape features of the targets using the geometric method. The experimental results showed that, compared with other algorithms, the accuracy of the proposed algorithm could reach more than 96%, the accuracy of navigation line extraction reached 98%, and the average detection time was 51 ms. The proposed method was robust and universal, and it can provide reliable navigation paths for the cuttage and film covering multi-functional machine. Full article
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Article
American Sign Language Alphabet Recognition Using Inertial Motion Capture System with Deep Learning
Inventions 2022, 7(4), 112; https://doi.org/10.3390/inventions7040112 - 01 Dec 2022
Viewed by 650
Abstract
Sign language is designed as a natural communication method for the deaf community to convey messages and connect with society. In American sign language, twenty-six special sign gestures from the alphabet are used for the fingerspelling of proper words. The purpose of this [...] Read more.
Sign language is designed as a natural communication method for the deaf community to convey messages and connect with society. In American sign language, twenty-six special sign gestures from the alphabet are used for the fingerspelling of proper words. The purpose of this research is to classify the hand gestures in the alphabet and recognize a sequence of gestures in the fingerspelling using an inertial hand motion capture system. In this work, time and time-frequency domain features and angle-based features are extracted from the raw data for classification with convolutional neural network-based classifiers. In fingerspelling recognition, we explore two kinds of models: connectionist temporal classification and encoder-decoder structured sequence recognition model. The study reveals that the classification model achieves an average accuracy of 74.8% for dynamic ASL gestures considering user independence. Moreover, the proposed two sequence recognition models achieve 55.1%, 93.4% accuracy in word-level evaluation, and 86.5%, 97.9% in the letter-level evaluation of fingerspelling. The proposed method has the potential to recognize more hand gestures of sign language with highly reliable inertial data from the device. Full article
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Article
Investigation and Numerical Simulation of the Acoustic Target Strength of the Underwater Submarine Vehicle
Inventions 2022, 7(4), 111; https://doi.org/10.3390/inventions7040111 - 01 Dec 2022
Viewed by 510
Abstract
Modern weapon systems’ survival hinges on their detection capabilities more than anything else. In the active sonar equation, the acoustic target strength is crucial. Under the assumption of plane wave propagation, the standard target strength equation is used to forecast the reradiated intensity [...] Read more.
Modern weapon systems’ survival hinges on their detection capabilities more than anything else. In the active sonar equation, the acoustic target strength is crucial. Under the assumption of plane wave propagation, the standard target strength equation is used to forecast the reradiated intensity for the far field. The ability of a submarine to remain unnoticed while on patrol or accomplishing a mission is its primary defense. Sonar, sometimes known as sound navigation ranging, is a popular method for locating submarines. This is because saltwater effectively absorbs radio frequencies. Sonar technology is used in more than just the commercial fishing business; it is also used in undersea research. The submarine’s designers consider the reflection of acoustic waves to minimize the amount of space required for such reflections. The Target Strength (TS) metric is used to assess the sonar objects’ size. This manuscript explains and demystifies the Benchmark Target Echo Strength Simulation (BeTTSi) benchmark submarine’s TS analysis. This model’s Pressure Acoustic-Boundary Element Model (PA-BEM) interface has been stabilized, and the model itself is pretty huge acoustically. Full article
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Article
A Fast and Cost-Effective (FACE) Instrument Setting to Construct Focus-Extended Images
Inventions 2022, 7(4), 110; https://doi.org/10.3390/inventions7040110 - 29 Nov 2022
Viewed by 1148
Abstract
Image stacking is a crucial method for micro or macro photography. It captures images at different focal planes and then merges them into a single, all-in-focus image with extended focus. This method has been extensively used for digital documentation by scientists working at [...] Read more.
Image stacking is a crucial method for micro or macro photography. It captures images at different focal planes and then merges them into a single, all-in-focus image with extended focus. This method has been extensively used for digital documentation by scientists working at museums or research institutions. However, the traditional image stacking method relies on expensive instruments to conduct precise image stacking using a computer-based stepper motor controller. In this study, we reported how to conduct image focus extensions with comparable quality to those done by a motorized stepper using a cost-effective instrument setting and an efficient manual stacking method. This method provides a shorter operation time and capability to capture images of living objects and high flexibility in obtaining the images of objects from cm to mm scale. However, it also has some limitations, including the inability to control aperture and exposure time, relatively short working distance at high magnification, requires additional steps to convert the video into images, and heavily relies on the user’s manual observation prior to a video recording. Nevertheless, the authors believe that the current method can be applied as an alternative method to conduct image stacking. The development of such an instrument and method offers a promising avenue for scientists to perform image stacking with greater flexibility and speed in macro photography. Full article
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Article
On the Avant-Garde IDeS Method for the Future of Car Design Applied to an SUV Project
Inventions 2022, 7(4), 106; https://doi.org/10.3390/inventions7040106 - 17 Nov 2022
Viewed by 698
Abstract
This case study aims to develop a new innovative SUV (Sport Utility Vehicle) model exploiting IDeS (Industrial Design Structure), which is an engineering approach conceived to optimize car design projects in the automotive industry like never before. A compact SUV was chosen because [...] Read more.
This case study aims to develop a new innovative SUV (Sport Utility Vehicle) model exploiting IDeS (Industrial Design Structure), which is an engineering approach conceived to optimize car design projects in the automotive industry like never before. A compact SUV was chosen because it is a type of vehicle that is highly requested by customers, and it is extremely successful in the market due to its versatility. In fact, compact SUVs are mixed vehicles that combine the pragmatism of a car with the typical robustness of an off-road vehicle making them suitable both for urban and off-road scenarios. The following pages will illustrate the steps followed for the realization of the final product using the SDE (Stylistic Design Engineering) method and other various design technologies, such as Quality Function Deployment (QFD), Benchmarking (BM) and Top Flop Analysis (TPA). In the final part of this project, the virtual prototyping of the product is carried out using Additive Manufacturing (AM) with an FDM 3D printer. The combination of these methods forms, to all intents and purposes, the IDeS, a newly developed innovative and cutting-edge discipline capable of schematically guiding the new product development process in companies with unprecedented efficiency. Full article
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Article
Periodontal Maintenance Therapy: Efficacy of Oral Irrigator in the Home Oral Hygiene Protocol Associated with Microbiological Analysis with Phase Contrast Microscope
Inventions 2022, 7(4), 104; https://doi.org/10.3390/inventions7040104 - 15 Nov 2022
Viewed by 564
Abstract
Objective: The aim of this research was to assess how the application of an oral irrigator modifies the subgingival bacterial flora in patients undergoing periodontal maintenance therapy. We used a qualitative microbiological analysis with a phase contrast microscope that can differentiate a non-pathogenic [...] Read more.
Objective: The aim of this research was to assess how the application of an oral irrigator modifies the subgingival bacterial flora in patients undergoing periodontal maintenance therapy. We used a qualitative microbiological analysis with a phase contrast microscope that can differentiate a non-pathogenic (immobile) bacterial flora from a pathogenic (mobile). Methods: In this study, 60 patients with a diagnosis of moderate periodontitis were enrolled. They were treated with non-surgical laser-assisted causal therapy and after one month a re-evaluation was performed that established the stabilization of the periodontal pathology. They were instructed in the home oral hygiene protocol with sonic toothbrush, interdental brushes and oral irrigator, and were included in the periodontal maintenance therapy program with a phase contrast microscope control every 6 months. At T0 phase contrast–phase microscopic examinations, the existence of non-pathogenic bacterial flora was displayed in all patients. They were then randomly divided into two groups, A and B. After professional oral hygiene treatment, group B suspended the usage of oral irrigator. Patients of group A, after the professional oral hygiene treatment, were motivated to continue their oral hygiene protocol at home. After three months, the patients underwent microscopic analysis of the bacterial plaque. Results: At T1 in Group B, 90% of patients had undergone a pathogenic bacterial flora change. In group A, in which patients kept using the oral irrigator for the three months, 100% of them showed immobile plaque on phase contrast microscopic analysis. Conclusions: This research showed that oral irrigator in the practice of home hygiene protocols plays a role in the long-term maintenance of a non-pathogenic bacterial flora in periodontal patients. Full article
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Article
Algebras of Vector Functions over Normed Fields
Inventions 2022, 7(4), 102; https://doi.org/10.3390/inventions7040102 - 14 Nov 2022
Viewed by 464
Abstract
This article is devoted to study of vector functions in Banach algebras and Banach spaces over normed fields. A structure of their Banach algebras is investigated. Banach algebras of vector functions with values in ∗-algebras, finely regular algebras, B-algebras, and operator [...] Read more.
This article is devoted to study of vector functions in Banach algebras and Banach spaces over normed fields. A structure of their Banach algebras is investigated. Banach algebras of vector functions with values in ∗-algebras, finely regular algebras, B-algebras, and operator algebras are scrutinized. An approximation of vector functions is investigated. The realizations of these algebras by operator algebras are studied. Full article
Article
Activated Plasma Albumin Gel (APAG) in Transalveolar Technique for Maxillary Sinus Lift: A Case Series
Inventions 2022, 7(4), 99; https://doi.org/10.3390/inventions7040099 - 26 Oct 2022
Viewed by 695
Abstract
Over the past 20 years, transalveolar techniques have progressively improved. They have become increasingly predictable and reliable, with the additional advantage of simplified procedures that are less operator dependent. The aim of this study is to evaluate the effectiveness of a new technique [...] Read more.
Over the past 20 years, transalveolar techniques have progressively improved. They have become increasingly predictable and reliable, with the additional advantage of simplified procedures that are less operator dependent. The aim of this study is to evaluate the effectiveness of a new technique to lift the maxillary sinus through a transalveolar approach, Simple Minimal Safe (SMS), with use of activated plasma albumin gel (APAG). A total of 33 patients (22 female and 11 male), aged between 36 and 79, were consecutively operated on, with 44 implants positioned using the SMS technique. All were placed in the premolar or molar areas of the maxillary bone. No implant was lost during the follow-up period (6 months) and all implants were then prosthetically loaded. The average bone gain was 4.43 mm. In the first quadrant, sites 15, 16 and 17 were involved with an average bone gain of 3.5 mm, 4.6 mm and 4.5 mm, respectively. In the second quadrant the sites 24, 25, 26 and 27 were involved with an average bone gain of 4.25 mm, 4.5 mm, 4.4 mm and 4.5 mm, respectively. Analyzing the data considering the sex, implants in women had an average gain of 4.66 mm, while in men the average gain was 3.83 mm. With the SMS technique, we achieved a reduction in post-operatory morbidity and in the frequency of Schneiderian membrane perforation. In conclusion, maxillary sinus augmentation via the transalveolar approach has become a more predictable surgical procedure and an easier technique due to less operator-dependent processes. Full article
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Article
Treatment of Medication-Related Osteonecrosis of the Jaw (MRONJ) with Er:YaG Laser and Ozone Therapy: A Case Series
Inventions 2022, 7(4), 97; https://doi.org/10.3390/inventions7040097 - 20 Oct 2022
Viewed by 693
Abstract
The purpose of this study is to evaluate the efficacy of the combination of ozone gel and Er:YAG laser treatment in respect of medication-related osteonecrosis of the jaw (MRONJ) for normal procedures. Consequently, the following techniques are compared in the study: medical therapy [...] Read more.
The purpose of this study is to evaluate the efficacy of the combination of ozone gel and Er:YAG laser treatment in respect of medication-related osteonecrosis of the jaw (MRONJ) for normal procedures. Consequently, the following techniques are compared in the study: medical therapy (MT); MT + conservative surgery with rotary/piezoelectric instruments; MT + ozone therapy; MT + surgical treatment + laser Er:YAG; and MT + ozone therapy + surgical treatment + laser Er:YAG. Fifty-seven patients with MRONJ stages I, II, and III were treated. The protocol was different for each group of patients and included MT, the application of an ozone gel, an Er:YAG laser surgery session, conservative surgery with rotary/piezoelectric instruments, or surgical treatment, and then the monitoring of healing for at least 12 months. The protocols were performed once a week until complete recovery. Patients were reassessed weekly for the first month after treatment, monthly for the following quarter, and then every 3 months until the end of one year. The radiographic surveys were carried out 6 and 12 months after the last treatment. All of the patients in Group 4 (treated with medical therapy + ozone therapy + surgical treatment + laser Er:YAG) achieved complete clinical and radiographic recovery (100%) with complete remission of osteonecrosis. The proposed combined treatment of ozone therapy using laser Er:YAG and the MT + surgical treatment allowed us to obtain excellent results in the resolution of MRONJ. This success was explained by a series of characteristics specific to laser technology; in fact, thanks to its photoacoustic, photochemical, photothermal, and photomechanical properties, the laser made it possible to reduce the bacterial load at the intervention site. Full article
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Article
Patterned Colouring via Variable-Speed Single Stretching
Inventions 2022, 7(4), 93; https://doi.org/10.3390/inventions7040093 - 12 Oct 2022
Viewed by 672
Abstract
We demonstrate a cost-effective, highly reliable/stable and environmentally friendly approach for the patterned colouring of a commercial transparent polyethylene terephthalate (PET). We show that different colour patterns (transparent, white/translucent, complete white/silver and different combinations of these three colours) can be realised in PET [...] Read more.
We demonstrate a cost-effective, highly reliable/stable and environmentally friendly approach for the patterned colouring of a commercial transparent polyethylene terephthalate (PET). We show that different colour patterns (transparent, white/translucent, complete white/silver and different combinations of these three colours) can be realised in PET strips upon varying the speed during continuous stretching. The conditions for good quality colour patterns are investigated, and the length of transient region during speed change is investigated. Full article
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Article
IDeS Method Applied to an Innovative Motorbike—Applying Topology Optimization and Augmented Reality
Inventions 2022, 7(4), 91; https://doi.org/10.3390/inventions7040091 - 10 Oct 2022
Viewed by 743
Abstract
This study is on the conception of the DS700 HYBRID project by the application of the Industrial Design Structure method (IDeS), which applies different tools sourced from engineering and style departments, including QFD and SDE, used to create the concept of a hybrid [...] Read more.
This study is on the conception of the DS700 HYBRID project by the application of the Industrial Design Structure method (IDeS), which applies different tools sourced from engineering and style departments, including QFD and SDE, used to create the concept of a hybrid motorbike that could reach the market in the near future. SDE is an engineering approach for the design and development of industrial design projects, and it finds important applications in the automotive sector. In addition, analysis tools such as QFD, comprising benchmarking and top-flop analysis are carried out to maximize the creative process. The key characteristics of the bike and the degree of innovation are identified and outlined, the market segment is identified, and the stylistic trends that are most suitable for a naked motorbike of the future are analyzed. In the second part the styling of each superstructure and of all the components of the vehicle is carried out. Afterwards the aesthetics and engineering perspectives are accounted for to complete the project. This is achieved with modelling and computing tools such as 3D CAD, visual renderings, and FEM simulations, and virtual prototyping thanks to augmented reality (AR), and finally physical prototyping with the use of additive manufacturing (AM). The result is a product conception able to compete in the present challenging market, with a design that is technically feasible and also reaches new lightness targets for efficiency. Full article
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Article
Study on Road Friction Database for Traffic Safety: Construction of a Road Friction-Measuring Device
Inventions 2022, 7(4), 90; https://doi.org/10.3390/inventions7040090 - 03 Oct 2022
Cited by 1 | Viewed by 650
Abstract
This study focuses on the possibility of constructing a database on friction coefficients for actual roads from the viewpoint of traffic safety. A measurement algorithm is established to construct a road friction-measuring device. Next, the tires are selected for use in the measurements [...] Read more.
This study focuses on the possibility of constructing a database on friction coefficients for actual roads from the viewpoint of traffic safety. A measurement algorithm is established to construct a road friction-measuring device. Next, the tires are selected for use in the measurements and their characteristics are measured using a bench tire characteristic tester. The measuring device is designed and constructed based on these characteristics. Finally, using this device, the measurement results of the road friction characteristics for two types of road surfaces are presented. Full article
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Article
Application of Fixed-Length Ultrasonic Interferometry to Determine the Kinetics of Light-/Heat-Induced Damage to Biological Membranes and Protein Complexes
Inventions 2022, 7(4), 87; https://doi.org/10.3390/inventions7040087 - 30 Sep 2022
Viewed by 800
Abstract
This manuscript describes the application of a fixed-length ultrasonic spectrometer to determine the kinetics of heat- and photo-induced damage to biological membranes and protein complexes and provides examples of the test measurements. We implemented a measurement scheme using the digital analysis of harmonic [...] Read more.
This manuscript describes the application of a fixed-length ultrasonic spectrometer to determine the kinetics of heat- and photo-induced damage to biological membranes and protein complexes and provides examples of the test measurements. We implemented a measurement scheme using the digital analysis of harmonic signals. To conduct the research, the fixed-length ultrasonic spectrometer was modernized: the speed was increased; lighting was supplied to the sample cells; the possibility of changing the gas atmosphere and mixing the sample was given. Using solutions containing natural concentrations of deuterium oxide, a high sensitivity of the spectrometer was shown. The spectrometer performed well in the measurement of phase state of dimyristoylphosphatidylcholine liposomes, both in the absence and in the presence of additions, which are capable of changing the lipid properties (sodium dodecyl sulfate, palmitic acid, and calcium ions). The heat- and photo-induced changes in the state of photosystem II core complexes were demonstrated using a fixed-length ultrasonic spectrometer. Transitions at 35.5 °C, 43.5 °C, 56.5 °C, and 66.7 °C were revealed. It is proposed that the transitions reflect the disassembly of the complexes and protein denaturation. Thus, the present study demonstrates that a fixed-length ultrasonic spectrometer can be applied to determine the kinetics of heat- and photo-induced damage to biological membranes and protein complexes. Full article
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Article
Stepped-Frequency Continuous-Wave Signal Processing Method for Human Detection Using Radars for Sensing Rooms through the Wall
Inventions 2022, 7(3), 79; https://doi.org/10.3390/inventions7030079 - 05 Sep 2022
Cited by 3 | Viewed by 917
Abstract
The problem of detecting moving and stationary people in a room with a specialized radar system sensing through the wall is considered in the paper. The high-range resolution of the system is achieved by effective processing of reflected ultra-wideband stepped-frequency continuous-wave signals (SFCW). [...] Read more.
The problem of detecting moving and stationary people in a room with a specialized radar system sensing through the wall is considered in the paper. The high-range resolution of the system is achieved by effective processing of reflected ultra-wideband stepped-frequency continuous-wave signals (SFCW). The paper presents a new method which is based on normalization of complex-valued samples of the received SFCW signals and extends traditional processing steps including quadrature-phase demodulation, sampling and inverse discrete Fourier transform. The proposed method is aimed at improving the performance of the interperiodic difference and variance of sample algorithms which are briefly described in relation to the SFCW radar system. The computer modeling showed that the introduced normalization mitigates the background noise and merely decreases the artifacts commonly appearing in radar images due to the non-uniform amplitude-frequency characteristics of the radar circuits. The described algorithms were implemented in a software part of the real-time working prototype of the radar system designed and assembled at the University research center. The results of field experiments confirmed the advantage of the proposed method in typical scenarios and showed the increase of the signal-to-noise ratio to 5 dB compared to traditional radar algorithm-processing SFCW signals. Full article
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Article
Several Aspects of Interaction between Chrome and Nanodiamond Particles in Metal Matrix Composites When Being Heated
Inventions 2022, 7(3), 75; https://doi.org/10.3390/inventions7030075 - 02 Sep 2022
Cited by 1 | Viewed by 813
Abstract
The paper considers the development of a technological scheme for preparing metal matrix nanocomposites based on the interaction between nanodiamond reinforcing particles and a chromium matrix when being heated, forming chromium carbide nanoparticles. These carbides are in situ synthesized ceramic reinforcing nanoparticles. The [...] Read more.
The paper considers the development of a technological scheme for preparing metal matrix nanocomposites based on the interaction between nanodiamond reinforcing particles and a chromium matrix when being heated, forming chromium carbide nanoparticles. These carbides are in situ synthesized ceramic reinforcing nanoparticles. The first stage of preparing composites is to obtain composites with the chromium matrix and nanodiamond reinforcing particles. For this purpose, mechanical alloying is used, i.e., processing in planetary mills. The size of a primary nanodiamond particle is 5 nm, but they are combined in agglomerates that are hundreds of micrometers in size. The time of processing in the planetary mill defines the crushing degree of the agglomerates. In this study, processing was carried out for 0.5 h, 2 h, and 4 h. The second stage for obtaining composites with reinforcing particles of chromium carbides is thermal processing. Explorations using the method of differential scanning calorimetry showed that reducing the size of nanodiamond reinforcing particles (by prolonging the time of processing in the planetary mill) leads to a decrease in the initial temperature of the reaction for developing carbides. The worked-out technique for obtaining composites was patented in the Russian Federation (the patent for invention 2772480). Full article
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Article
Biosafety Construction Composite Based on Iron Oxide Nanoparticles and PLGA
Inventions 2022, 7(3), 61; https://doi.org/10.3390/inventions7030061 - 20 Jul 2022
Cited by 3 | Viewed by 1296
Abstract
Nanocomposites based on polymers and nanoparticles are used in agriculture for photoconversion of solar radiation, as a basis for covering material, as a packaging material, and as functional films. At the same time, nanocomposites are almost never used in agriculture as biosafe structural [...] Read more.
Nanocomposites based on polymers and nanoparticles are used in agriculture for photoconversion of solar radiation, as a basis for covering material, as a packaging material, and as functional films. At the same time, nanocomposites are almost never used in agriculture as biosafe structural materials. In this work, we have developed a technology for obtaining a nanocomposite based on PLGA and iron oxide nanoparticles. The nanocomposite has unique physical and chemical properties and also exhibits pronounced antibacterial properties at a concentration of iron oxide nanoparticles of more than 0.01%. At the same time, the nanocomposite does not affect the growth and development of pepper and is biocompatible with mammalian cells. Nanocomposites based on PLGA and iron oxide nanoparticles can be an attractive candidate for the manufacture of structural and packaging materials in agriculture. Full article
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Article
The Application of X-ray Micro-CT in the Study of HTS Tape Coils
Inventions 2022, 7(3), 60; https://doi.org/10.3390/inventions7030060 - 14 Jul 2022
Viewed by 994
Abstract
In the process of manufacturing products from high-temperature superconductors (HTS), quality control must be carried out. Traditionally, for HTS coils, electrical tests are carried out to determine critical current. In the case of an unacceptable result, it is necessary to determine the cause. [...] Read more.
In the process of manufacturing products from high-temperature superconductors (HTS), quality control must be carried out. Traditionally, for HTS coils, electrical tests are carried out to determine critical current. In the case of an unacceptable result, it is necessary to determine the cause. Therefore, it is necessary to develop nondestructive testing methods. This article proposes a technology for manufacturing quality evaluation. It is based on determining the actual location of the tape and the gaps between the turns and rows of the coil and analyzing these values. For this purpose, samples were scanned using computed tomography (CT) with a Nordson Dage XD7600NT X-ray inspection system with a μCT module. The obtained data were analyzed using VolumeGraphics VGStudio 2.2 software. Furthermore, the proposed technology can be used as part of a predictive analysis of the state of HTS coils in the windings of electrical machines. Full article
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Article
Research and Development of Trinary Power Cycles
Inventions 2022, 7(3), 56; https://doi.org/10.3390/inventions7030056 - 04 Jul 2022
Cited by 2 | Viewed by 1112
Abstract
The most effective and environmentally safe fossil fuel power production facilities are the combined cycle gas turbine (CCGT) ones. Electric efficiency of advanced facilities is up to 58% in Russia and up to 64% abroad. The further improvement of thermal efficiency by increase [...] Read more.
The most effective and environmentally safe fossil fuel power production facilities are the combined cycle gas turbine (CCGT) ones. Electric efficiency of advanced facilities is up to 58% in Russia and up to 64% abroad. The further improvement of thermal efficiency by increase of the gas turbine inlet temperature (TIT) is limited by performance of heat resistance alloys that are used for the hot gas path components and the cooling system efficiency. An alternative method for the CCGT efficiency improvement is utilization of low potential heat of the heat recovery steam generator (HRSG) exhaust gas in an additional cycle operating on a low-boiling heat carrier. This paper describes a thermodynamic analysis of the transition from binary cycles to trinary ones by integration of the organic Rankine cycle (ORC). A mathematical model of a cooled gas turbine plant (GT) has been developed to carry out calculations of high-temperature energy complexes. Based on the results of mathematical modeling, recommendations were made for the choice of the structure and parameters of the steam turbine cycle, as well as the ORC, to ensure the achievement of the maximum thermal efficiency of trinary plants. It is shown that the transition from a single pressure CCGT to a trinary plant allows the electric power increase from 213.4 MW to 222.7 MW and the net efficiency increase of 2.14%. The trinary power facility has 0.45% higher efficiency than the dual pressure CCGT. Full article
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Article
Calculation and Experimental Study of Low-Cycle Fatigue of Gas Turbine Engines Booster Drum
Inventions 2022, 7(3), 49; https://doi.org/10.3390/inventions7030049 - 23 Jun 2022
Cited by 1 | Viewed by 871
Abstract
A calculation-experimental study of durability of titanium booster drum of gas turbine engine (GTE) was carried out. A methodology of experimental estimation of titanium component life of GTE using structurally similar elements (SSE) has been proposed. A series of three-dimensional calculations by the [...] Read more.
A calculation-experimental study of durability of titanium booster drum of gas turbine engine (GTE) was carried out. A methodology of experimental estimation of titanium component life of GTE using structurally similar elements (SSE) has been proposed. A series of three-dimensional calculations by the finite element method of SSE cut out of the finished part was carried out to estimate the strength of the booster drum. A methodology for testing the durability of SSE in the low-cycle fatigue (LCF) area was developed, and statistical processing of the test results was performed. Tests of SSE allowed carrying out advanced-edge assessment of the durability of a full-size drum, taking into account the manufacturing technology. Full article
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Article
Incorporating Human Preferences in Decision Making for Dynamic Multi-Objective Optimization in Model Predictive Control
Inventions 2022, 7(3), 46; https://doi.org/10.3390/inventions7030046 - 21 Jun 2022
Viewed by 815
Abstract
We present a new two-step approach for automatized a posteriori decision making in multi-objective optimization problems, i.e., selecting a solution from the Pareto front. In the first step, a knee region is determined based on the normalized Euclidean distance from a hyperplane defined [...] Read more.
We present a new two-step approach for automatized a posteriori decision making in multi-objective optimization problems, i.e., selecting a solution from the Pareto front. In the first step, a knee region is determined based on the normalized Euclidean distance from a hyperplane defined by the furthest Pareto solution and the negative unit vector. The size of the knee region depends on the Pareto front’s shape and a design parameter. In the second step, preferences for all objectives formulated by the decision maker, e.g., 50–20–30 for a 3D problem, are translated into a hyperplane which is then used to choose a final solution from the knee region. This way, the decision maker’s preference can be incorporated, while its influence depends on the Pareto front’s shape and a design parameter, at the same time favorizing knee points if they exist. The proposed approach is applied in simulation for the multi-objective model predictive control (MPC) of the two-dimensional rocket car example and the energy management system of a building. Full article
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Article
Blitz Vision: Development of a New Full-Electric Sports Sedan Using QFD, SDE and Virtual Prototyping
Inventions 2022, 7(2), 41; https://doi.org/10.3390/inventions7020041 - 08 Jun 2022
Cited by 1 | Viewed by 1575
Abstract
In this paper, industrial design structure (IDeS) is applied for the development of two new full-electric sports sedan car proposals that go by the names Blitz Vision AS and Retro. With a deep analysis of the trends dominating the automotive industry, a [...] Read more.
In this paper, industrial design structure (IDeS) is applied for the development of two new full-electric sports sedan car proposals that go by the names Blitz Vision AS and Retro. With a deep analysis of the trends dominating the automotive industry, a series of product requirements was identified using quality function deployment (QFD). The results of such analysis led to the definition of the technical specifications of the product via benchmarking (BM) and top-flop analysis (TFA). The product architecture was then defined by making use of a modular platform chassis capable of housing a variety of vehicle bodyworks. The structured methodology of stylistic design engineering (SDE) was used. This can be divided in six phases: (1) stylistic trends analysis; (2) sketches; (3) 2D CAD drawings; (4) 3D CAD models; (5) virtual prototyping; (6) solid stylistic model. The chassis of the CAD model was verified structurally by means of FEM analysis, whereas the drag coefficients of the two vehicle proposals were compared with one of the main competitor’s vehicles via CFD simulations. The resulting car models are both aesthetically appealing and can be further developed, leading eventually to the production stage. This proves the effectiveness of IDeS and SDE in car design. Full article
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Article
Thermal Performance Improvement by Rotating Thermosyphon Loop in Rotor of an Interior Permanent Magnet Synchronous Electric Motor
Inventions 2022, 7(2), 37; https://doi.org/10.3390/inventions7020037 - 05 May 2022
Viewed by 1321
Abstract
As an attempt to enable a further increase in the power-to-weight ratio of an electric motor by improving its cooling performance, rotating thermosyphon loops in a rotor of a permanent magnet synchronous electric motor are proposed. The effective thermal conductivity and airflow heat-transfer [...] Read more.
As an attempt to enable a further increase in the power-to-weight ratio of an electric motor by improving its cooling performance, rotating thermosyphon loops in a rotor of a permanent magnet synchronous electric motor are proposed. The effective thermal conductivity and airflow heat-transfer rate of the rotating thermosyphon loop and the convective heat-transfer coefficient over the annular interior surface of the air chamber are measured to permit the definition of the thermal boundary conditions for simulating the temperature fields of the electric motors. The axial heat-transfer pathway with extremely high effective thermal conductivity attributing to the phase-change activities in the rotating thermosyphon loop acts synergistically with the heat convection enhancement induced by the stirring effect of the spinning condenser bend in the air chamber to improve the heat transmission out of the rotor core. The spatially average temperature gradients in the rotor with the thermosyphon loops are considerably moderated from those without the thermosyphon loop. At rotor speeds and electrical currents in the ranges of 1200–1500 rev/min and 1000–1200 A, the maximum temperatures in the rotors with the single- and twin-end rotating thermosyphon loops are, respectively, reduced 8–14 °C and 10–22 °C from those without a rotor-cooling scheme, affirming the effectiveness of a phase-change cooling device in a rotor for thermal performance improvement of an electric motor. Full article
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Article
IDeS (Industrial Design Structure) Method Applied to the Automotive Design Framework: Two Sports Cars with Shared Platform
Inventions 2022, 7(2), 36; https://doi.org/10.3390/inventions7020036 - 07 Apr 2022
Cited by 1 | Viewed by 2101
Abstract
The present study was set to validate two different suburban-type sportscar bodies with shared common underpinnings. The chosen method to develop this project was the Industrial Design Structure (IDeS), which characterizes the ability to use the different innovative techniques known within the industrial [...] Read more.
The present study was set to validate two different suburban-type sportscar bodies with shared common underpinnings. The chosen method to develop this project was the Industrial Design Structure (IDeS), which characterizes the ability to use the different innovative techniques known within the industrial field, across the whole organization. This method is embodied by following a series of structured analysis tools, such as QFD (Quality Function Deployment), Benchmarking (BM), Top-Flop analysis (TFA), Stylistic Design Engineering (SDE), Prototyping, Testing, Budgeting and Planning. This project aims to study the present-day car market and to foresee deployment in the near future. This attempt was confirmed by delivering the complete styling and technical feasibility characteristics of two different sports cars, obtained by the IDeS methodology. This approach of embodying design together with phases of product development would provide a better engineered, target-oriented product, that uses state-of-the-art style and CAD environments to reduce product development time and, hence, overall Time to Market (TTM). Full article
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Correction
Correction: Majeed, A.; Lee, S. Towards Privacy Paradigm Shift Due to the Pandemic: A Brief Perspective. Inventions 2021, 6, 24
Inventions 2022, 7(1), 28; https://doi.org/10.3390/inventions7010028 - 25 Feb 2022
Viewed by 1296
Abstract
The authors made a mistake while publishing this paper [...] Full article
Article
Mechanism Cleaning of the Ear Canal
Inventions 2022, 7(1), 20; https://doi.org/10.3390/inventions7010020 - 30 Jan 2022
Viewed by 2292
Abstract
The cleaning of the ear canal is very important, and it is crucial that it is performed by an otolaryngologist as it requires a high level of competence and skill. The accumulation of cerumen or earwax in the ear canal is one of [...] Read more.
The cleaning of the ear canal is very important, and it is crucial that it is performed by an otolaryngologist as it requires a high level of competence and skill. The accumulation of cerumen or earwax in the ear canal is one of the most commonly observed problems in patients, and ignoring it may cause hearing loss, irritation and discomfort. There are a number of techniques that have been utilized in the past for cleaning the ear canal, including irrigation, i.e., curettage and water pick, and syringing. There are many patients who are unable to clean their ear canal through a natural self-cleaning process. The main aim of this study is to develop a unique model for ear cleaning free of irritation or discomfort, especially for those patients who have disorders of the self-cleaning ear canal process. The tool is designed specifically considering patient safety and comfort. However, the commercialization of this tool requires research and modification for improved quality results considering primarily the patient’s health. Full article
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Review
The Latest Advances in Wireless Communication in Aviation, Wind Turbines and Bridges
Inventions 2022, 7(1), 18; https://doi.org/10.3390/inventions7010018 - 29 Jan 2022
Cited by 3 | Viewed by 2682
Abstract
Present-day technologies used in SHM (Structural Health Monitoring) systems in many implementations are based on wireless sensor networks (WSN). In the context of the continuous development of these systems, the costs of the elements that form the monitoring system are decreasing. In this [...] Read more.
Present-day technologies used in SHM (Structural Health Monitoring) systems in many implementations are based on wireless sensor networks (WSN). In the context of the continuous development of these systems, the costs of the elements that form the monitoring system are decreasing. In this situation, the challenge is to select the optimal number of sensors and the network architecture, depending on the wireless system’s other parameters and requirements. It is a challenging task for WSN to provide scalability to cover a large area, fault tolerance, transmission reliability, and energy efficiency when no events are detected. In this article, fundamental issues concerning wireless communication in structural health monitoring systems (SHM) in the context of non-destructive testing sensors (NDT) were presented. Wireless technology developments in several crucial areas were also presented, and these include engineering facilities such as aviation and wind turbine systems as well as bridges and associated engineering facilities. Full article
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Article
Improvement of the Liquefied Natural Gas Vapor Utilization System Using a Gas Ejector
Inventions 2022, 7(1), 14; https://doi.org/10.3390/inventions7010014 - 14 Jan 2022
Cited by 4 | Viewed by 1829
Abstract
The production, transportation, and storage of liquefied natural gas (LNG) is a promising area in the gas industry due to a number of the fuel’s advantages, such as its high energy intensity indicators, its reduced storage volume compared to natural gas in the [...] Read more.
The production, transportation, and storage of liquefied natural gas (LNG) is a promising area in the gas industry due to a number of the fuel’s advantages, such as its high energy intensity indicators, its reduced storage volume compared to natural gas in the gas-air state, and it ecological efficiency. However, LNG storage systems feature a number of disadvantages, among which is the boil-off gas (BOG) recovery from an LNG tank by flaring it or discharging it to the atmosphere. Previous attempts to boil-off gas recovery using compressors, in turn, feature such disadvantages as large capital investments and operating costs, as well as low reliability rates. The authors of this article suggest a technical solution to this problem that consists in using a gas ejector for boil-off gas recovery. Natural gas from a high-pressure gas pipeline is proposed as a working fluid entraining the boil-off gas. The implementation of this method was carried out according to the developed algorithm. The proposed technical solution reduced capital costs (by approximately 170 times), metal consumption (by approximately 100 times), and power consumption (by approximately 55 kW), and improved the reliability of the system compared to a compressor unit. The sample calculation of a gas ejector for the boil-off gas recovery from an LNG tank with a capacity of 300 m3 shows that the ejector makes it possible to increase the boil-off gas pressure in the system by up to 1.13 MPa, which makes it possible to not use the first-stage compressor unit for the compression of excess vapours. Full article
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Article
DSP Processer-in-the-Loop Tests Based on Automatic Code Generation
Inventions 2022, 7(1), 12; https://doi.org/10.3390/inventions7010012 - 11 Jan 2022
Cited by 1 | Viewed by 1517
Abstract
The digital signal processing (DSP) processor-in-the-loop tests based on automatic code generation technology are studied. Firstly, the idea of model-based design is introduced, and the principle and method of embedded code automatic generation technology are analyzed by taking the automatic code generation of [...] Read more.
The digital signal processing (DSP) processor-in-the-loop tests based on automatic code generation technology are studied. Firstly, the idea of model-based design is introduced, and the principle and method of embedded code automatic generation technology are analyzed by taking the automatic code generation of the DSP control algorithm for pulse width modulation (PWM) output as an example. Then, the control system model is established on MATLAB/Simulink. After verifying the model through simulation, the target board platform is established with DSP as the core processor, and the automatically generated code is tested by the processor-in-the-loop (PIL). The results show that the technology greatly shortens the development cycle of the project, improves the robustness and consistency of the control code, and can be widely used in the complex algorithm development process of the controller, from intelligent design and modeling to implementation. Full article
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2021

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Article
The Mathematical Models of the Operation Process for Critical Production Facilities Using Advanced Technologies
Inventions 2022, 7(1), 8; https://doi.org/10.3390/inventions7010008 - 30 Dec 2021
Viewed by 1296
Abstract
The paper presents data on the problems of monitoring and diagnosing the technical conditions of critical production facilities, such as torpedo ladle cars, steel ladles. The accidents with critical production facilities, such as torpedo ladle cars, lead to losses and different types of [...] Read more.
The paper presents data on the problems of monitoring and diagnosing the technical conditions of critical production facilities, such as torpedo ladle cars, steel ladles. The accidents with critical production facilities, such as torpedo ladle cars, lead to losses and different types of damages in the metallurgical industry. The paper substantiates the need for a mathematical study of the operation process of the noted critical production facilities. A Markovian graph has been built that describes the states of torpedo ladle cars during their operation. A mathematical model is presented that allows determining the optimal frequency of diagnostics of torpedo ladle cars, which, in contrast to the existing approaches, take into account the procedures for preventive diagnostics of torpedo ladle cars, without taking them out of service. Dependence of the utilization coefficient on the period of diagnostics of PM350t torpedo ladle cars was developed. The results (of determining the optimal period of diagnostics for PM350t torpedo ladle cars) are demonstrated. The system for automated monitoring and diagnosing the technical conditions of torpedo ladle cars, without taking them out of service, has been developed and described. Full article
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Article
Production of PP Composites Reinforced with Flax and Hemp Woven Mesh Fabrics via Compression Molding
Inventions 2022, 7(1), 5; https://doi.org/10.3390/inventions7010005 - 21 Dec 2021
Cited by 4 | Viewed by 1985
Abstract
Hemp and flax fibers are among the most interesting vegetable fibers that can be used to reinforce polymeric matrices. In line with the global environmental requests, the use of these fibers especially coupled with thermoforming polymers are increasing more and more in order [...] Read more.
Hemp and flax fibers are among the most interesting vegetable fibers that can be used to reinforce polymeric matrices. In line with the global environmental requests, the use of these fibers especially coupled with thermoforming polymers are increasing more and more in order to expand their applications and replace synthetic fibers and thermosetting plastics. However, one of the major limitations of vegetable fibers is their poor adhesion with polymeric matrices that is often overcome by fibers chemical treatments or by using coupling agents within the matrix. Aiming to produce polypropylene (PP) bio composite laminates reinforced by hemp and flax fibers without additional process steps, this paper deals on the study of their production via the compression molding technique by using woven fabrics characterized by a large mesh size able to ensure a mechanical anchoring between fibers and matrix. Two different forming strategies that differ in the time required for reaching the maximum values of compression pressure and in the dwelling time at this value were used in order to investigate how the yarn impregnation was affected by them. To expand the applications of composites under investigation, tensile, bending, Izod, heat deflection temperature (HDT) and bearing tests were carried out. The results highlighted how the use of a waiting time before the reaching of the maximum moulding pressure allowed a better matrix flow within the vegetable yarn leading to higher mechanical performances. Full article
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Article
The Operation of a Three-Bladed Horizontal Axis Wind Turbine under Hailstorm Conditions—A Computational Study Focused on Aerodynamic Performance
Inventions 2022, 7(1), 2; https://doi.org/10.3390/inventions7010002 - 21 Dec 2021
Cited by 1 | Viewed by 2106
Abstract
The aim of this study is the aerodynamic degradation of a three-bladed Horizontal Axis Wind Turbine (HAWT) under the influence of a hailstorm. The importance and originality of this study are that it explores the aerodynamic performance of an optimum wind turbine blade [...] Read more.
The aim of this study is the aerodynamic degradation of a three-bladed Horizontal Axis Wind Turbine (HAWT) under the influence of a hailstorm. The importance and originality of this study are that it explores the aerodynamic performance of an optimum wind turbine blade during a hailstorm, when hailstones and raindrops are present. The commercial Computational Fluid Dynamics (CFD) code ANSYS Fluent 16.0 was utilized for the simulation. The first step was the calculation of the optimum blade geometry characteristics for a three-bladed rotor, i.e., twist and chord length along the blade, by a user-friendly application. Afterwards, the three-dimensional blade and the flow field domain were designed and meshed appropriately. The rotary motion of the blades was accomplished by the application of the Moving Reference Frame Model and the simulation of hailstorm conditions by the Discrete Phase Model. The SST k–ω turbulence model was also added. The produced power of the wind turbine, operating in various environmental conditions, was estimated and discussed. Contours of pressure, hailstone and raindrop concentration and erosion rate, on both sides of the blade, are presented. Moreover, contours of velocity at various cross sections parallel to the rotor are demonstrated, to understand the effect of hailstorms on the wake behavior. The results suggest that the aerodynamic performance of a HAWT degrades due to impact and breakup of the particles on the blade. Full article
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Article
Effects of In-Process Temperatures and Blending Polymers on Acrylonitrile Butadiene Styrene Blends
Inventions 2021, 6(4), 93; https://doi.org/10.3390/inventions6040093 - 24 Nov 2021
Viewed by 1576
Abstract
Acrylonitrile butadiene styrene (ABS) is a renowned commodity polymer for additive manufacturing, particularly fused deposition modelling (FDM). The recent large-scale applications of 3D-printed ABS require stable mechanical properties than ever needed. However, thermochemical scission of butadiene bonds is one of the contemporary challenges [...] Read more.
Acrylonitrile butadiene styrene (ABS) is a renowned commodity polymer for additive manufacturing, particularly fused deposition modelling (FDM). The recent large-scale applications of 3D-printed ABS require stable mechanical properties than ever needed. However, thermochemical scission of butadiene bonds is one of the contemporary challenges affecting the overall ABS stability. In this regard, literature reports melt-blending of ABS with different polymers with high thermal resistance. However, the comparison for the effects of different polymers on tensile strength of 3D-printed ABS blends was not yet reported. Furthermore, the cumulative studies comprising both blended polymers and in-process thermal variables for FDM were not yet presented as well. This research, for the first time, presents the statistical comparison of tensile properties for the added polymers and in-process thermal variables (printing temperature and build surface temperature). The research presents Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) to explain the thermochemical reasons behind achieved mechanical properties. Overall, ABS blend with PP shows high tensile strength (≈31 MPa) at different combinations of in-process parameters. Furthermore, some commonalities among both blends are noted, i.e., the tensile strength improves with increase of surface (bed) and printing temperature. Full article
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Article
Efficient Model for Accurate Assessment of Frequency Support by Large Populations of Plug-in Electric Vehicles
Inventions 2021, 6(4), 89; https://doi.org/10.3390/inventions6040089 - 18 Nov 2021
Cited by 3 | Viewed by 1503
Abstract
In recent years, plug-in electric vehicles (PEVs) have gained immense popularity and are on a trajectory of constant growth. As a result, power systems are confronted with new issues and challenges, threatening their safety and reliability. PEVs are currently treated as simple loads [...] Read more.
In recent years, plug-in electric vehicles (PEVs) have gained immense popularity and are on a trajectory of constant growth. As a result, power systems are confronted with new issues and challenges, threatening their safety and reliability. PEVs are currently treated as simple loads due to their low penetration. However, as their numbers are growing, PEVs could potentially be exploited as distributed energy storage devices providing ancillary services to the network. Batteries used in PEVs are developed to deliver instantaneously active power, making them an excellent solution for system frequency support. This paper proposes a detailed dynamic model that is able to simulate frequency support capability from a large number of PEVs, using an innovative aggregate battery model that takes into account the most significant constraints at PEV and aggregate battery levels. The cost optimization algorithm, which is the most time-consuming process of the problem, is executed only at the aggregate battery level, thereby reducing the computational requirements of the model without compromising the obtained accuracy. The proposed method is applied to the power system of Crete exploiting detailed statistical data of EV mobility. It is proven that PEVs can effectively support power system frequency fluctuations without any significant deviation from their optimal operation. Full article
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Article
Operation Safety of a 2-DoF Planar Mechanism for Arm Rehabilitation
Inventions 2021, 6(4), 85; https://doi.org/10.3390/inventions6040085 - 15 Nov 2021
Viewed by 1528
Abstract
The operation safety of rehabilitation devices must be addressed early in the development process and before being tested on people. In this paper, the operation safety of a 2-DoF (degrees of freedom) planar mechanism for arm rehabilitation is addressed. Then, the safety and [...] Read more.
The operation safety of rehabilitation devices must be addressed early in the development process and before being tested on people. In this paper, the operation safety of a 2-DoF (degrees of freedom) planar mechanism for arm rehabilitation is addressed. Then, the safety and efficiency of the device operation is assessed through the Transmission Index (TI) distribution in its workspace. Furthermore, the produced stresses on the human arm are assessed via the FEM (finite element method) when the rehabilitation device reaches five critical positions within its workspace. The TI distribution showed that the proposed design has a proper behaviour from a force transmission point of view, avoiding any singular configuration that might cause a control failure and subsequent risk for the user and supporting the user’s motion with a good efficiency throughout its operational workspace. The FEM analysis showed that Nurse operation is safe for the human arm since a negligible maximum stress of 6.55 × 103 N/m2 is achieved by the human arm when the device is located on the evaluated critical positions. Full article
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Article
Design and Research Sowing Devices for Aerial Sowing of Forest Seeds with UAVs
Inventions 2021, 6(4), 83; https://doi.org/10.3390/inventions6040083 - 10 Nov 2021
Cited by 1 | Viewed by 3088
Abstract
Modern unmanned aerial vehicles (UAV) can be effectively used for aerial sowing of forests. A feature of aerial sowing is the possibility of rapid reforestation at low costs, which is extremely important in the current environmental situation. The purpose of this study is [...] Read more.
Modern unmanned aerial vehicles (UAV) can be effectively used for aerial sowing of forests. A feature of aerial sowing is the possibility of rapid reforestation at low costs, which is extremely important in the current environmental situation. The purpose of this study is to develop a set of sowing devices intended for use with UAVs. For this, the metering devices and seed distribution devices were analyzed, used on the UAV or having prospects for such use. The existing studies of metering devices, implemented by numerical methods, are analyzed. Further, the synthesis of eight different designs of sowing devices in the 3D CAD was carried out and their comparative assessment was completed in terms of mass and a set of technological parameters. Based on its results, a sowing device was selected that is most suitable for a specific given technology. Discrete Element Method (DEM) was used to simulate the workflow: imitation of loading of the sowing device, study of work in various modes, study of the process of impact interaction of seeds with the soil environment. The complex of developed sowing devices can provide sowing of almost any type of forest seeds within the framework of various technologies and soil climatic conditions. Full article
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