Search Results (633)

Background: There is an emerging need for new scalable behavioral assays, i.e., assays that are feasible to administer from the comfort of the person’s home, with ease and at higher frequency than clinical visits or visits to laboratory settings can afford us today. This need poses several challenges which we address in this work along with scalable solutions for behavioral data acquisition and analyses aimed at diversifying various populations under study here and to encourage citizen-driven participatory models of research and clinical practices. Methods: Our methods are centered on the biophysical fluctuations unique to the person and on the characterization of behavioral states using standardized biorhythmic time series data (from kinematic, electrocardiographic, voice, and video-based tools) in naturalistic settings, outside a laboratory environment. The methods are illustrated with three representative studies (58 participants, 8–70 years old, 34 males, 24 females). Data is presented across the nervous systems under a proposed functional taxonomy that permits data organization according to nervous systems’ maturation and decline levels. These methods can be applied to various research programs ranging from clinical trials at home, to remote pedagogical settings. They are aimed at creating new standardized biometric scales to screen and diagnose neurological disorders across the human lifespan. Results: Using this remote data collection system under our new unifying statistical platform for individualized behavioral analysis, we characterize the digital ranges of biophysical signals of neurotypical participants and report departure from normative ranges in neurodevelopmental and neurodegenerative disorders. Each study provides parameter spaces with self-emerging clusters whereby data points corresponding to a cluster are probability distribution parameters automatically classifying participants into different continuous Gamma probability distribution families. Non-parametric analysis reveals significant differences in distributions’ shape and scale (p < 0.01). Data reduction is realizable from full probability distribution families to a single parameter, the Gamma scale, amenable to represent each participant within each subclass, and each cluster of similar participants within each cohort. We report on data integration from stochastic analyses that serve to differentiate participants and propose new ways to highly scale our research, education, and clinical practices. Conclusions: This work highlights important methodological and analytical techniques for developing personalized and scalable biometrics across various populations outside a laboratory setting. Full article

Climate change and urbanization are intensifying the urban heat island effect and negatively impacting outdoor thermal comfort in cities. Innovative planning strategies are required to design more livable and resilient urban spaces. Building on a state of the art of current Urban Digital Twins (UDTs) for outdoor thermal comfort analysis, this paper presents the design and implementation of a functional UDT prototype. Developed for a pilot area in Huelva, Spain, the system integrates real-time environmental data, spatial modeling, and simulation tools within an open-source architecture. The literature reveals that while UDTs are increasingly used in urban management, their application to outdoor thermal comfort remains limited and technically challenging, especially in terms of real-time data, modeling accuracy, and user interaction. The case study demonstrates the feasibility of a modular, open-source UDT capable of simulating mean radiant temperature and outdoor thermal comfort indexes at high resolution and visualizing the results in a 3D interactive environment. UDTs have strong potential for supporting microclimate-sensitive planning and improving outdoor thermal comfort. However, important challenges remain, particularly in simulation efficiency, model detail, and stakeholder accessibility. The proposed prototype addresses several of these gaps and provides a basis for future improvements. Full article

This paper presents the final implemented design and performance evaluation of the ground-based C-band Cheia radar system, developed to enhance Romania’s contribution to the EU Space Surveillance and Tracking (EU SST) network. All data used for performance analysis are real-time, real-life measurements of true spatial test objects orbiting Earth. The radar is based on two decommissioned 32 m satellite communication antennas already present at the Cheia Satellite Communication Center, that were retrofitted for radar operation in a quasi-monostatic architecture. A Linear Frequency Modulated Continuous Wave (LFMCW) Radar design was implemented, using low transmitted power (2.5 kW) and advanced software-defined signal processing for detection and tracking of Low Earth Orbit (LEO) targets. System validation involved dry-run acceptance tests and calibration campaigns with known reference satellites. The radar demonstrated accurate measurements of range, Doppler velocity, and angular coordinates, with the capability to detect objects with radar cross-sections as low as 0.03 m² at slant ranges up to 1200 km. Tracking of medium and large Radar Cross Section (RCS) targets remained robust under both fair and adverse weather conditions. This work highlights the feasibility of re-purposing legacy satellite infrastructure for SST applications. The Cheia radar provides a cost-effective, EUSST-compliant performance solution using primarily commercial off-the-shelf components. The system strengthens the EU SST network while demonstrating the advantages of LFMCW radar architectures in electromagnetically congested environments. Full article

In response to the IMO’s decarbonisation strategy, hydrogen—especially green hydrogen—becomes a promising alternative fuel in shipping. This article provides a comparative analysis of two hydrogen propulsion technologies suitable for a service vessel (SOV) operating in offshore wind farms: hydrogen fuel cells and hydrogen-powered internal combustion engines. This study focuses on the use of liquid hydrogen (LH₂) stored in cryogenic tanks and fuel cells as an alternative to the previously considered solution based on compressed hydrogen (CH₂) stored in high-pressure cylinders (700 bar) and internal combustion engines. The research aims to examine the feasibility of a fully hydrogen-powered SOV energy system. The analyses showed that the use of liquefied hydrogen in SOVs leads to the threefold reduction in tank volume (1001 m³ LH₂ vs. 3198 m³ CH₂) and the weight of the storage system (243 t vs. 647 t). Despite this, neither of the technologies provides the expected 2-week autonomy of SOVs. LH₂ storage allows for a maximum of 10 days of operation, which is still an improvement over the CH₂ gas variant (3 days). The main reason for this is that hydrogen tanks can only be located on the open deck. Although hydrogen fuel cells take up on average 13.7% more space than internal combustion engines, they are lower (by an average of 24.3%) and weigh less (by an average of 50.6%), and their modular design facilitates optimal arrangement in the engine room. In addition, the elimination of the exhaust system and lubrication simplifies the engine room layout, reducing its weight and space requirements. Most importantly, however, the use of fuel cells eliminates exhaust gas emissions into the atmosphere. Full article

Background/Objectives: Vertical ridge augmentation remains a challenging procedure in alveolar bone reconstruction, with existing techniques often limited by surgical complexity, graft instability, and high resorption rates. This study evaluates the clinical and histological outcomes of a novel vertical ridge augmentation technique using a wide-head tenting pole screw (WHTPS) combined with sticky bone graft material. Methods: Five patients with vertical bone deficiencies (6–10 mm) in the maxilla or mandible underwent augmentation using a single WHTPS (rectangular or round wide-head type). Sticky bone was prepared using autologous tooth bone, allografts, or xenografts, combined with fibrin glue and covered with concentrated growth factor (CGF) membranes and/or resorbable collagen membranes. After 5–6 months of healing, the WHTPS was removed, and bone biopsies were taken for histological analysis. Results: Radiographic and histological evaluations confirmed successful ridge augmentation in all cases. Newly formed bone ranged from 21.2% to 57.5%. All patients proceeded to implant placement without complications. Radiographic, clinical, and histological assessments consistently showed that new bone formation extended up to the level of the screw head, indicating complete vertical fill of the augmented space. Histology showed well-integrated, mineralized bone with no signs of inflammation. The wide-head tenting pole screw was observed to support stable space maintenance and facilitate surgical handling and favorable outcomes in vertical ridge augmentation. Conclusions: In this case series, a single wide-head tenting pole screw appeared sufficient to maintain space and resist soft tissue pressure in wide alveolar bone defects during healing. This case series suggests that the wide-head tenting pole screw technique may be a feasible option for managing severe alveolar bone deficiencies. Full article

Government-managed urban green spaces in Bangkok produce large quantities of leaf waste, which are typically sent to landfills, incurring considerable costs. This study assessed a novel method for valorizing this waste by converting dried, ground leaf material into compressed planting blocks (PL) to serve as a soil substitute. Annual leaf waste data from three government agencies were used to estimate production capacity and inform economic modeling. Agronomic trials with Mitragyna speciosa (Korth.) Havil. compared PL, coconut fiber (PC), and mixed soil with fertilizer over eight weeks in controlled nursery conditions. The results indicated that PL supported plant growth with a final mean height of 20.10 ± 2.01 cm, similar to PC (20.70 ± 1.90 cm) and significantly greater than soil (14.40 ± 1.50 cm) (p < 0.001). Economic analysis showed high net present values (THB 9.16–13.76 million) and very short payback periods (less than 0.08 years). The process proved technically feasible and profitable, while also reducing waste disposal costs, minimizing landfill emissions, and providing a cost-effective, biodegradable planting medium. This method presents a scalable solution for sustainable organic waste management in tropical urban areas, supporting several Sustainable Development Goals and advancing the circular bioeconomy. Full article

This study investigates the application potential of large language models (LLMs), particularly GPT-4o, in generating geometric parameter suggestions during the early stages of structural design. Design recommendations from the LLM are validated using a finite-element solver (FFE Plus solver), forming the core workflow of the proposed approach. To assess its effectiveness, the LLM’s performance is compared against traditional regression-based surrogate models, which serve as baseline references. A two-hole hanger bracket serves as the case study, evaluating prediction accuracy, data efficiency, generalization capability, and workflow complexity across three materials: 6061-T6, AISI 304, and AISI 1020. The key evaluation indicators include safety factor (SF) and Mass. The results show that the regression models offer high accuracy and interpretability but require extensive amounts of simulation data; in this study, each material required 252 samples to adequately cover the design space. In contrast, GPT-4o produced feasible design suggestions using only 18 initial samples, combining semantic prompting and finite-element analysis. Its prediction accuracy improved significantly with a small number of iterations, demonstrating superior data efficiency and cross-material adaptability. Overall, the findings suggest that, when paired with appropriate prompting strategies and validation mechanisms, LLMs hold great promise as an assistive tool in early-stage structural design optimization. Full article

With the acceleration of climate change and urbanisation, Chinese cities are facing increasingly severe flood risks. To address this challenge, China began implementing its sponge city policy in 2013, leveraging low-impact development, green infrastructure construction, and integrated water resource management to enhance urban resilience to floods and improve water security. This study utilises the Web of Science database as a reference, retrieving 201 relevant literature sources. From these, 61 studies closely related to China’s sponge city policy and urban flood management were selected. CiteSpace was employed to conduct keyword co-occurrence and temporal evolution analyses, comprehensively outlining the research hotspots and developmental trajectory of this field. The results indicate that research content has gradually shifted from early engineering-based flood control models to multi-objective, interdisciplinary comprehensive management, encompassing flood risk assessment, policy implementation mechanisms, integration of green infrastructure, and economic feasibility analysis. Based on this, this paper constructs an analytical framework incorporating technical, environmental, institutional, and social dimensions to integrate existing research findings, while identifying gaps in cross-scale coordination, smart management, and public participation. The research conclusions can provide valuable references for future policy optimisation and urban sustainable development. Full article

Severe pressure pulsations caused by complex flow fields in pumped-storage power stations significantly threaten operational safety and stability. With advances in computational technology, fully three-dimensional simulations coupling pipelines and pump-turbine units have become feasible. In this study, a fully three-dimensional analysis model was developed, coupling the water conveyance system and a finely modeled prototype-scale pump-turbine with splitter blades, to numerically simulate the compressible flow field under the maximum head pump mode. The study reveals a strong bidirectional coupling between the flow in the long outlet pipe and the internal flow within the pump-turbine unit. Influenced by structural features such as bifurcations and flow impingement at the T-junction, complex three-dimensional vortices arise and cannot be neglected. Based on the flow field, the study further investigates the time-domain, frequency-domain, and spatial characteristics of pressure pulsations at various downstream hydraulic components, ranging from the vaneless space to the outlet of the long outlet pipe. The pressure pulsation frequencies are shown to be affected by both rotor–stator interactions and the complex vortical structures in the flow. These findings clearly demonstrate the necessity of fully three-dimensional simulations that incorporate both the water conveyance system and the pump-turbine unit. Full article

To address stability and safety issues in hydraulic support design under inclined–declined and large-dip-angle working conditions, this paper proposes a design-driven dynamic pose–load co-evolution solution method based on the physical entity of the ZFY12000/21/36D hydraulic support. The feasibility of the proposed method is demonstrated through theoretical analysis, spatial modeling, and experimental verification. First, a spatial coordinate system describing hydraulic support pose is established based on Denavit–Hartenberg (DH) theory, constructing a “physical space-geometric coordinate system-DH parameter space” pose mapping model via DH principles, matrix iteration, and kinematic simulation. Second, a load-bearing characteristic analytical method is developed through systematic coupling analysis of dip angle, pose, and load distribution. Finally, coal mine field data collection and hydraulic support test platform experiments analyze load-bearing characteristics under varying poses and loads. Results show Root Mean Square Error (RMSE) values of 0.836° for the front link inclination, 0.756° for the rear link, 0.114° for the balance ram, and 0.372° for the column; load-bearing state evolution under pose–load synergy aligns with theoretical models, confirming method feasibility. This approach fills a domain gap in hydraulic support dip–pose–load co-solving and provides critical references for designing hydraulic support products under extreme dip-angle operations. Full article

The inter-satellite laser interferometer, which functions as a high-performance displacement sensor, will be used in forthcoming space-based gravitational wave detection missions. The readout of these interferometers is typically performed by phasemeters based on all-digital phase-locked loops (ADPLLs) implemented in FPGAs. This paper proposes a feasible loop parameter design workflow and a comprehensive noise model, providing guidelines for designing and optimizing an ADPLL to meet specified bandwidth and precision requirements. The validity of our analysis is demonstrated through numerical performance measurements based on the modified digital splitting test. Full article

A bioresorbable cannulated bone screw was developed using PLA/PCL-based composites reinforced with hydroxyapatite (HA) and titanium dioxide (TiO₂), two additives previously reported to enhance mechanical compliance, biocompatibility, and molding feasibility in biodegradable polymer systems. The design incorporated a crest-trimmed thread and a strategically positioned gate in the thin-wall zone opposite the hexagonal socket to preserve torque-transmitting geometry during micromolding. To investigate shrinkage behavior, a Taguchi orthogonal array was employed to systematically vary micromolding parameters, generating a structured dataset for training a back-propagation neural network (BPNN). Analysis of variance (ANOVA) identified melt temperature as the most influential factor affecting shrinkage quality, defined by a combination of shrinkage rate and dimensional variation. A hybrid AI framework integrating the BPNN with genetic algorithms and particle swarm optimization (GA–PSO) was applied to predict the optimal shrinkage conditions. This is the first use of BPNN–GA–PSO for cannulated bone screw molding, with the shrinkage rate as a targeted output. The AI-predicted solution, interpolated within the Taguchi design space, achieved improved shrinkage quality over all nine experimental groups. Beyond the specific PLA/PCL-based systems studied, the modeling framework—which combines geometry-specific gate design and normalized shrinkage prediction—offers broader applicability to other bioresorbable polymers and hollow implant geometries requiring high-dimensional fidelity. This study integrates composite formulation, geometric design, and data-driven modeling to advance the precision micromolding of biodegradable orthopedic devices. Full article

A mill relining manipulator is key maintenance equipment for liners exchanged and operated by workers inside a grinding mill. To improve the operation efficiency and safety, real-time path planning and end deformation compensation should be performed prior to actual execution. This paper proposes a five-dimensional digital twin framework to realize virtual–real interaction between a physical manipulator and virtual model. First, a real-time digital twin scene is established based on OpenGL. The involved technologies include scene rendering, a camera system, the light design, model importation, joint control, and data transmission. Next, different solving methods are introduced into the service space for relining tasks, including a kinematics model, collision detection, path planning, and end deformation compensation. Finally, a user application is developed to realize real-time condition monitoring and simulation analysis visualization. Through comparison experiments, the superiority of the proposed path planning algorithm is demonstrated. In the case of a long-distance relining task, the planning time and path length of the proposed algorithm are 1.7 s and 15,299 mm, respectively. For motion smoothness, the joint change curve exhibits no abrupt variation. In addition, the experimental results between original and modified end trajectories further verified the effectiveness and feasibility of the proposed end effector compensation method. This study can also be extended to other heavy-duty manipulators to realize intelligent automation. Full article

This study introduces a novel space feasibility assessment process and evaluates its effectiveness through a comparative analysis with a conventional manual process. The proposed method is designed to enhance spatial comprehension and integrate building performance analysis, thereby supporting budgetary considerations during the early design phase. By providing a more intuitive and interactive environment, the system enables stakeholders—such as building owners—to communicate their spatial requirements to architects and professionals more clearly and efficiently. To validate the effectiveness of the proposed approach, participants completed two distinct scenarios: (1) a manual space feasibility assessment, and (2) a system-supported space feasibility assessment utilizing the proposed method. Participant performance was measured in terms of speed and accuracy in each scenario. Additionally, a user satisfaction survey was conducted to evaluate the usability of the system’s functionality. The experimental results provide an empirical basis for comparing the proposed process with the manual approach. Findings demonstrate that the proposed process enables more efficient and accurate space feasibility assessments, thereby validating its effectiveness as a user-centered decision-support tool during early-stage architectural planning. Full article

To address the challenge of determining the borehole layout scheme in the practical application of high-pressure gas expansion rock breaking, this study takes the excavation of the safety passage at Kaixuan Road Station on the North Extension Line 2 of Chongqing Metro Line 18 as the engineering background. The rock-breaking capacity was evaluated by analyzing the damaged zone volume caused by gas expansion using FLAC3D 6.0 numerical simulation software, and vibration monitoring was conducted for the historical buildings on the surface. This study revealed the following: (1) When the borehole depth is 1.2 m and the charge length is 0.6 m, the optimal angle is 70°, with the optimal vertical and horizontal spacing between holes being 1200 mm and 2000 mm, respectively. (2) The numerical simulations indicated that by adjusting the charge density, the optimized sandstone borehole network parameters could be applied to mudstone strata, and the rock-breaking effect was similar. The difference in the volume of the damaged zones obtained in the two strata was less than 3%. (3) The vibration analysis demonstrated that the peak particle velocity generated by high-pressure gas expansion rock fracturing at the ancient building directly above was 0.06316 cm/s, which was lower than the threshold value of 0.1 cm/s and approximately 67.95% lower than that of explosive blasting. Furthermore, when the tunnel depth exceeded 29 m, the vibration velocity of surface structures remained within the safety range. The results verified the feasibility of applying the same borehole network parameters to different strata, providing theoretical support for the practical application of high-pressure gas expansion rock fracturing technology in engineering projects. Full article