Applied Sciences

Person re-identification (Re-ID) is a key technology used in the field of intelligent surveillance. The existing Re-ID methods are mainly realized by using convolutional neural networks (CNNs), but the feature information is easily lost in the operation process due to the down-sampling structure design in CNNs. Moreover, CNNs can only process one local neighbourhood at a time, which makes the global perception of the network poor. To overcome these shortcomings, in this study, we apply a pure transformer to a video-based Re-ID task by proposing an adaptive partitioning and multi-granularity (APMG) network framework. To enable the pure transformer structure better at adapting to the Re-ID task, we propose a new correlation-adaptive partitioning (CAP) of feature embedding modules that can adaptively partition person images according to structural correlations and thus retain the structure and semantics of local feature information in the images. To improve the Re-ID performance of the network, we also propose a multi-granularity (MG) module to better capture people feature information at different levels of granularity. We performed validation trials on three video-based benchmark datasets. The results show that the network structure based on the pure transformer can adapt to Re-ID tasks well, and our APMG network outperforms other state-of-the-art methods. Full article

Transport is one of the sectors with the highest greenhouse gas emissions (GHG) that is imperative to reduce in order to decrease global warming. Although modern vehicles and arterial roads have adopted technological and structural improvements to enhance fuel use efficiency, the emission of greenhouse gases (GHG) into the atmosphere by the transport sector has been increasing in different Mexican cities. In generating mitigation strategies, modeling scenarios of decreased equivalent carbon dioxide, CO₂e emissions, may be useful as an evaluation tool. In this study, the aim was to model a trend scenario and a scenario, including improvements with a projection to the year 2039 on one of the main urban roads of the border city of Mexicali, Mexico. In order to create a dynamic emission model of GHG, including emission factors, the main variables for the simulation were vehicle volume, travels, motor performance, and fuel consumption. These last two parameters were the most important for vehicular emissions estimations and for the projection of them in this period. As a result of the projections, CO₂e was observed to increase in a trend scenario, while modeled improvement actions resulted in emission reductions of up to 5%. The model showed that the key variable to achieve this reduction is vehicle engine performance (Pf), whose increase factor was 1.1% per year. Replicating this methodology to evaluate and mitigate the GHG emissions on different city roads or in other cities, can be a contribution for the urban designers, authorities, and involved institutions. Full article

In the present study, an attempt was made to enrich cookies with ground seeds of milk thistle (Silybum marianum L.) and to determine the effect of this addition on the quality of cookies. The content of nutrients, fibre, and calorific value, as well as, texture, spreadability factor, volume, colour and sensory parameters were tested. The biscuits were characterized by lower caloric value, hardness and volume, but higher spreadability. The cookies with 5% of milk thistle gained high consumer acceptance, but greater than 20% addition caused a worsening quality of the product. The biscuit fortification with ground milk thistle seeds seems to be justified, through enrichment of the products with fibre and the antioxidant compounds having health-promoting properties. Full article

Activated carbon (AC) is one of the most used air purification materials with excellent adsorption capacity for volatile organic compounds (VOCs). In this work, Bi₂O₂CO₃ (BOC) nanomaterials, as a photocatalysis component, are grown on the surface of the AC to construct BOC/AC composites. The as-synthesized composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and N₂ adsorption/desorption measurements. The results demonstrate that flower-like BOC can be grown in situ on the surface of AC. The photocatalytic properties for the removal of gaseous toluene (50.0 ppm) in air over the BOC/AC composites were investigated under simulated sunlight illumination. The results show that the BOC/AC photocatalyst can effectively degrade toluene to CO₂ and H₂O, with more than 90% degradation in 3 h. The excellent photocatalytic performance of the BOC/AC composite catalyst can be ascribed to the synergistic effect of the adsorption ability of AC and photocatalytic activity of both BOC nanosheets and AC. This work may provide useful guidance for indoor air purification, particularly for harmful trace gases such as VOCs. Full article

Saving fuel by splitting a flight mission with an intermediate stop for refuelling is described by the concept of intermediate stop operations. This can also be beneficial to the climate impact of aviation, if the flight level and intermediate stop airport are selected accordingly. This study aims to estimate the mitigation potential of an implementation of climate-optimised intermediate stop operations for European long-haul flights and compare it to fuel-optimal operations. For this purpose, fuel consumption and emissions are simulated along four-dimensional trajectories for the selected annual flight plan, and their average temperature response is calculated. A comparison between the reference case and climate-optimised as well as fuel-optimised scenarios shows a significant climate mitigation potential and reveals a shift of trajectories to lower latitudes and altitudes. However, increased flight times and fuel consumption limit implementation from stakeholders’ perspectives. Full article

The engineering technology of undercrossing an airport flight area is relatively mature; however, the use of shield tunnels crossing the operating airport flight area in high liquidity sandy cobble stratum has rarely been reported. To discuss the feasibility of a double-line shield tunnel undercrossing the airport flight area in a sandy cobble region. Based on the case of the Chengdu Metro Line 10 that undercrosses the Shuang-Liu Airport, which is located in sandy cobble region, the deformation and stress laws of airport runway pavement structures were investigated via a three-dimensional numerical model. Stratum displacement, ground settlement and pavement tensile stress under different tunnel depths were analysed. Then, the pavement tensile stress was taken as the safety evaluation index and the vulnerable area of the pavement structure was proposed. The results show that after excavation of the double-line tunnel, the maximum ground surface settlement occurred above the tunnel centreline and the ground settlement curves presented a V-type settlement trough instead of a W-type. The existence of a runway greatly limited the deformation of the surrounding soil; with increasing depth, the effect degree of the runway pavement on the soil settlement decreased. The most unfavourable region of the runway pavement structure under the influence of tunnel excavation was found. With increasing burial depth, the maximum settlement of the surface centre point decreased continuously. It is recommended that the tunnel burial depth not exceed 23.5 m in this project. According to the displacement and stress control limitation of the airport pavement, it can be judged that the shield construction method meets the structural stability requirements of the pavement. The calculated results provide a reference for the shield tunnel construction in the same geological condition areas. Full article

Due to the widespread integration of renewable energy sources connected to AC and DC power systems by means of power electronics converters, electromagnetic noise propagates along lines, and metallic earth-return structures. EMI filters are commonly used to mitigate the common mode and differential mode noise at the interface of distribution lines, and their suppression characteristics are usually assessed in standard test setups, the impedances of which are, however, scarcely representative of real-world applications. In this paper, an online, inductively coupled impedance measurement method is proposed. A sensitivity analysis to highlight the benefits of the proposed setup and experimental verification is performed. The proposed method enables non-intrusive impedance measurement in energized systems, including power converters. These measures, in turn, allow the evaluation of modal insertion losses of EMI filters in real-world operating conditions. The three-phase example considered in this study shows significant deviations from manufacturer specifications, thus justifying the need for more advanced estimation techniques. Full article

The lack of a complete and reliable data series often represents the main difficulty in carrying out climate studies. Diverse causes, such as human and instrumental errors, false and incomplete records, and the use of obsolete equipment in some meteorological stations, give rise to inhomogeneities that do not represent climatic reality. This work in the northern part of the Moroccan Middle Atlas used 22 meteorological stations with sometimes-incomplete monthly precipitation data from 1970 to 2019. The homogenization and estimation of the missing data were carried out with the R software package Climatol version 3.1.1. The trends in the series were quantified by the Mann–Kendall nonparametric test. The results obtained show a low root mean square error (RMSE), between the original and homogenized data, of between 0.5 and 38.7 mm per month, with an average of 8.5 mm. Rainfall trends for the months of December through June are generally downward. These negative trends are significantly stronger in the southern and eastern parts of the study area, especially during the month of April (the wettest month). On the other hand, July shows positive trends, with 71% of stations having an increasing precipitation tendency, although only five (or 1/3) of these are statistically significant. From August to November, generally positive trends were also observed. For these months, the percentage of series with a positive and significant trend varied between 55 and 77%. Full article

Data from past earthquakes is an important tool to reveal the impact of future earthquakes on engineering structures, especially in earthquake-prone regions. These data are important indicators for revealing the seismic loading effects that structures will be exposed to in future earthquakes. Five different earthquakes from six countries with high seismic risk were selected and were within the scope of this study. The measured peak ground acceleration (PGA) for each earthquake was compared with the suggested PGA for the respective region. Structural analyzes were performed for a reinforced-concrete (RC) building model with four different variables, including the number of storeys, local soil types, building importance class and concrete class. Target displacements specified in the Eurocode-8 were obtained for both the suggested and measured PGA values for each earthquake. The main goal of this study is to reveal whether the proposed and measured PGA values are adequately represented in different countries. We tried to reveal whether the seismic risk was taken into account at a sufficient level. In addition, target displacements have been obtained separately in order to demonstrate whether the measured and suggested PGA values for these countries are adequately represented in structural analysis and evaluations. It was concluded that both seismic risk and target displacements were adequately represented for some earthquakes, while not adequately represented for others. Comments were made about the existing building stock of the countries considering the obtained results. Full article

For the effect of two-sided sudden surcharge/unloading on existing shield tunnels, an indoor dimensional reduction model test was conducted at a scale of 1:15.5, measuring the ground settlement, lateral convergence of the shield tunnel, and additional surrounding pressure after changing the location and soil quality of surcharge/unloading, and an analysis was carried out. The results showed that the location of the maximum transverse convergence value of the existing shield tunnel is related to the position of the surcharge; when surcharging on both sides of the tunnel, as the position of the left surcharge’s offset increases from 0.2 m to 0.6 m, the transverse convergence value of the tunnel first increases and then becomes smaller; the ground settlement value of each measurement point in the unloading process also increases and then becomes smaller. The settlement value of each measurement point first increases and then decreases, and the alleviation effect of unloading on ground settlement is not obvious; after surcharge on one side of the tunnel, if the other side continues to surcharge, it will lead to a continued increase in the surrounding pressure. Unloading can effectively reduce the additional surrounding pressure of the tunnel, but the additional surrounding pressure cannot be immediately and completely eliminated; compared with dry sand, the maximum value of lateral convergence of the tunnel in wet sand is significantly decreased, and the peak value of ground settlement on both sides is not significant; when both sides are surcharged to 172 kg, the additional soil pressure of the tunnel’s subsoil shows three peaks, one of which occurs at measurement point 4 at the bottom of the tunnel, which may be due to the occurrence of stress concentration at the location. Full article

The growing trend of private car ownership in Malaysia is increasing traffic congestion. As part of a solution, the Malaysian Automotive Association (MAA) chose to develop technologies for an electric bus system in Kuala Lumpur and initiated a project to design and engineer an electric bus system with a focus on Human Centred Design (HCD) principles. In order to fulfil this a total of 28-hours of user observation was conducted in Kuala Lumpur (KL), Malaysia. Alongside this field research an online questionnaire study of future users (n = 102, Age 21–35) was conducted to further substantiate findings. As a result, we address the need for HCD considerations to be included in sustainable public transport systems in Malaysia. User observation revealed six key issues associated with the daily routine of a commuter which were then used to inform the questionnaire survey. Alarmingly, the survey revealed that over 60 per cent of respondents had never used the bus system in Kuala Lumpur stating problems such as frequency, comfort, driver attitude and bus shelter access. This provided a necessary platform for improvement resulting in eight key recommendations ranked by importance with the aim to increase bus usage in Malaysia. Full article

Acts of fraud have become much more prevalent in the financial industry with the rise of technology and the continued economic growth in modern society. Fraudsters are evolving their approaches continuously to exploit the vulnerabilities of the current prevention measures in place, many of whom are targeting the financial sector. To overcome and investigate financial frauds, this paper presents STALITA, which is an innovative platform for the analysis of bank transactions. STALITA enables graph-based data analysis using a powerful Neo4j graph database and the Cypher query language. Additionally, a diversity of other supporting tools, such as support for heterogeneous data sources, force-based graph visualisation, pivot tables, and time charts, enable in-depth investigation of the available data. In the Results section, we present the usability of the platform through real-world case scenarios. Full article

Textile-reinforced concrete (TRC) has many advantages, including corrosion resistance, but TRC is a novel composite material and there is limited experimental research on the flexural behavior of TRC members. This paper aims to experimentally evaluate the flexural behavior of TRC slabs reinforced with nine types of grid-type carbon fiber-reinforced plastic (CFRP) (hereafter referred to as carbon grid) with varying cross-sectional areas, spacings, tensile strengths, and elastic moduli of longitudinal strands. The experimental results show that the maximum load tends to be higher in specimens reinforced with carbon grids with small cross-sectional areas and spacings of strands but high tensile strength. Cross-sectional area and spacing were also revealed to influence the crack-formation stage behavior. On the other hand, stiffness decreased to approximately 8% or lower than the initial stiffness, with cracking in all carbon grid-reinforced specimens; post-peak behavior also exhibited dependency on tensile stress acting on the carbon grids under the maximum load, based on 80% of the tensile strength. Full article

This study investigated the impact of subcritical water extraction parameters on the polyphenols and flavonoids content in extracts made of the bark of walnut (Juglans regia L.), as well as antioxidant activity measured using the DPPH and FRAP methods. The total polyphenols (TPC) and flavonoid (TFC) were determined using the spectrophotometric (UV-Vis) method. The response surface methodology (RSM) was employed to optimize the yield of bioactive compounds. On the basis of developed model, the highest polyphenols (192.2 mg (GAE)/100 g (dry mass)) (GAE—gallic acid equivalent), flavonoids (88.3 mg(QE)/100 g (dry mass)) (QE—quercetin equivalent) contents and antioxidant activity (21.3∙10⁻⁶ MTE/1 g (dry mass)) (TE-Trolox equivalent) were obtained under the following extraction conditions: temperature 131.6 °C, raw material fraction size 0.9 mm and process time 10 min. The greatest impact on the extraction yield was observed in the case of the temperature, whereas the raw material fraction size and the process time had a secondary impact. Obtained results indicate that a smaller particle size and a shorter time may improve the process; however, a reduction in particle size can be challenging for a pressure cell filtration system and consequently increase the cost of the raw material pretreatment process. With the reduction in the process time, a lower cost of extract production can be achieved. This study confirmed the importance of a proper selection of extraction parameters to obtain the demanded extract composition. Full article

Prioritized experience replay (PER) is an important technique in deep reinforcement learning (DRL). It improves the sampling efficiency of data in various DRL algorithms and achieves great performance. PER uses temporal difference error (TD-error) to measure the value of experiences and adjusts the sampling probability of experiences. Although PER can sample valuable experiences according to the TD-error, freshness is also an important character of experiences. It implicitly reflects the potential value of experiences. Fresh experiences are produced by virtue of the current networks and they are more valuable for updating the current network parameters than the past. The sampling of fresh experiences to train the neural networks can increase the learning speed of the agent, but few algorithms can perform this job efficiently. To solve this issue, a novel experience replay method is proposed in this paper. We first define that the experience freshness is negatively correlated with the number of replays. A new hyper-parameter, the freshness discounted factor $\mu$, is introduced in PER to measure the experience freshness. Further, a novel experience replacement strategy in the replay buffer is proposed to increase the experience replacement efficiency. In our method, the sampling probability of fresh experiences is increased by raising its priority properly. So the algorithm is more likely to choose fresh experiences to train the neural networks during the learning process. We evaluated this method in both discrete control tasks and continuous control tasks via OpenAI Gym. The experimental results show that our method achieves better performance in both modes of operation. Full article

Lower limb movement disorders caused by various reasons are an important public health problem currently facing the world. To solve this problem, a novel spatial 8R mechanism with a stable structure and motion performance for human hip joint rehabilitation is proposed. Since the human body mainly performs coronal and sagittal plane movements, a spatial 8R mechanism with 2-DOF was designed to assist patients in rehabilitation training considering their actual circumstances. Based on the analysis of the Jacobian matrix and its condition number, the kinematics model and kinematics equation of the 8R mechanism in space were established. The mechanism has complete isotropic kinematics in single abduction and adduction, forward flexion and backward extension, and good dexterity and operability within the scope of the workspace; the correctness of the kinematics equation of the spatial 8R mechanism was verified by using the ADAMS software and theoretical calculation, and the regular variations of the mechanism’s movement in one period under different motions were obtained. We concluded that the spatial 8R mechanism has a stable performance and can move smoothly. Full article

The safety and reliability of a ventilation system relies on an accurate friction resistance coefficient (α), but obtaining α requires a great deal of tedious measurement work in order to determine the result, and many erroneous data are obtained. Therefore, it is vital that α be obtained quickly and accurately for the ventilation system design. In this study, a passive and active support indicator system was constructed for the prediction of α. An RF model, GSCV-RF model and BP model were constructed using the RF algorithm, GSCV algorithm and BP neural network, respectively, for α prediction. In the GSCV-RF and BP models, 160 samples complied with the prediction indicator system and were used to construct a prediction dataset and, this dataset was divided into a training set and a test set. The prediction results were based on the quantitative evaluation models of MAE, RMSE and R². The results show that, among the three models, the GSCV-RF model’s prediction result for α was the best, the RF model performed well and the BP model performed worst. In the prediction for all the datasets obtained by GSCV-RF model, all the values of MAE and RMSE were less than 0.5, the values of R² were more than 0.85 and the value of R² of the passive and active support test sets were 0.8845 and 0.9294, respectively. This proved that the GSCV-RF model can offer a more accurate α and aid in the reasonable design and the safe operation of a ventilation system. Full article

Unilateral vocal fold polyps can lead to incomplete glottal closure and irregular vocal fold vibration. Depending on polyp size and resulting dysphonia severity, voice therapy or surgery may be recommended. As part of voice therapy, patients may learn how to optimize intrinsic and extrinsic laryngeal muscle use to mitigate benign lesion effects, increase vocal efficiency, and improve voice quality. In this study, we used a low-dimensional mass model with a simulated unilateral vocal fold polyp and varied intra-laryngeal muscle activity to simulate vocal fold vibration across varied conditions. Differing muscle activation has different effects on frequency, periodicity, and intensity. Accordingly, learning how to optimize muscle activity in a unilateral polyp setting may help patients achieve the best possible periodic and most efficiently produced voice in the context of abnormal vocal fold morphology. Full article

With the increase in the complexity of communication systems, order statistics have become increasingly significant in performance evaluation, especially for advanced diversity techniques over fading channels. However, existing analytical approaches are not useful owing to their high complexity. In this paper, we present novel and insightful statistical results of the partial sums of ordered Gamma-distributed random variables. By adopting a unified analytical framework to obtain the desired joint probability density function from the joint moment-generating function, we redefine and derive the common key functions specialized for the Gamma distribution. The derived formula is presented in the form of either general closed-form expressions or at least a single integral form instead of the originally complicated multiple-integral form. In terms of a feasible application of our results, we present a complete and general closed-form analysis of the statistics of the combined received signal-to-noise ratio of the distributed cyclic delay diversity with the cyclic prefix single-carrier scheme. We also show that our analytical results can provide potential mathematical solutions for other wireless communication systems. Selected numerical examples are presented and discussed to illustrate the effectiveness of the applied approach and related results. All the derived analytical results were compared and verified by using Monte Carlo simulations to verify the accuracy of our analysis. Full article