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The integration of a composite of porous medium with phase change material (PCM) offers significant advantages in thermal management systems, enhancing heat transfer efficiency and addressing various thermal regulation challenges. This approach utilizes the PCM's latent heat absorption and the enhanced thermal conductivity provided by the porous medium, resulting in optimized system performance. Its applicability spans across electronics cooling and building insulation systems. However, predicting the thermal behavior of this composite material is challenging, necessitating computational tools to anticipate its response under different conditions and evaluate its influence on cooling strategies. The objective of this study is to create a computational tool specifically tailored to evaluate constitutive parameters of this composite material, thereby providing a comprehensive description of its thermal behavior. To achieve this goal, the multiscale homogenization principle is employed to assess the composite's effective thermophysical material properties using the representative volume element approach. The repeating unit cell of the aluminum lattice is incorporated into the PCM to define a representative volume element. The finite element method (FEM) is utilized to solve the three-dimensional homogenization problem, yielding an orthotropic effective thermal conductivity due to the inherent symmetry of the repeating material cell. Moreover, the study leverages the apparent heat capacity method to effectively manage the phase transitions within the PCM domain, utilizing smooth and temperature-dependent functions to accurately describe the thermophysical properties of the PCM. Integrating the composite into battery pack thermal management, this study thoroughly examines thermal dynamics by comparing outcomes with and without PCM integration. The transient thermal problem is accurately tackled using the FEM, employing the evaluated effective constitutive parameters of the homogenized composite to minimize computational effort. The results indicate a notable decline in the highest temperatures of the battery pack, leading to a reduction of about 14 °C at the specific moment when the phase change material fully transitions into its liquid form. The obtained results emphasize the effectiveness and practical feasibility of the proposed thermal management strategy. The modeling approach presented provides a robust tool with significant efficiency in reducing computational time for analyzing the thermal behavior of large models, as the utilization of the homogenization technique notably decreases the computational time. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Outgassing of human-landed objects on the Moon create high-density local atmospheres. • Airlocks, rovers, landers, backpacks, mining of ice, and trash were considered. • Backpacks, airlock releases, and landers can create locally collisional atmospheres. • Anthropogenic water makes an assessment of the natural environment difficult. • Gas releases from mining operations and trash to gas are uncertain at present. Outgassing from materials, whether through the ascent/descent stages of lunar vehicles, airlock depressurizing, rover or astronaut suit outgassing, may cause an effect of unwanted accumulation of volatiles at the surface and exosphere. This is especially important at (or proximal) to permanently shadowed regions (PSRs) at the lunar poles. Herein, we provide estimates of expected outgassing from various human-landed objects on the Moon, including backpacks, airlocks, rovers, landers, trash and mining operations. Astronaut suits produce some level of oxygen outgassing (Helou et al., 2022), which may transport and condense in these PSRs, even in micro- cold traps (Glavin et al., 2010).We estimate the outgassing from drill mining and trash-to-gas conversion assuming a specific technology is operating. These outgassing systems can create local, temporary atmospheres in the vicinity (∼100 km radius) of the sources. The atmosphere may be particularly high within meters of the source. To obtain column densities for these temporary atmospheres, we first bracket ranges for the gas number loss as a function of time. We then derive the maximum distance traveled and the time the released molecules remain in the exosphere for a single ballistic hop, assuming the molecules are ejected from the surface of the object at its surface temperature. In some cases, such as the astronaut backpack and the rover, the temperature is that of the source. Given this information, an average and peak local exospheric density and column density can be estimated. We find that backpacks, airlock releases, and the Starship lander can create relatively high-density local atmospheres, with local near-lander outgassing water densities exceeding 107/cm3. This local water exosphere is over 106 times greater than the LADEE-derived lower limit of the natural water exosphere at ∼3/cm3. Thus, the anthropogenic temporary water exosphere will likely dominate the environment near the lander, making an assessment of the natural exospheric water environment difficult. [ABSTRACT FROM AUTHOR]

The 1 | s-batch (∞) , r j | ∑ w j U j scheduling problem takes as input a batch setup time Δ and a set of n jobs, each having a processing time, a release date, a weight, and a due date; the task is to find a sequence of batches that minimizes the weighted number of tardy jobs. This problem was introduced by Hochbaum and Landy (Oper Res Lett 16(2):79–86, 1994); as a wide generalization of Knapsack, it is NP -hard. In this work, we provide a multivariate complexity analysis of the 1 | s-batch (∞) , r j | ∑ w j U j problem with respect to several natural parameters. That is, we establish a classification into fixed-parameter tractable and W [ 1 ] -hard problems, for parameter combinations of (i) # p = number of distinct processing times, (ii) # w = number of distinct weights, (iii) # d = number of distinct due dates, (iv) # r = number of distinct release dates. Thereby, we significantly extend the work of Hermelin et al. (Ann Oper Res 298:271–287, 2018) who analyzed the parameterized complexity of the non-batch variant of this problem without release dates. As one of our key results, we prove that 1 | s-batch (∞) , r j | ∑ w j U j is W [ 1 ] -hard parameterized by the number of distinct processing times and distinct due dates. To the best of our knowledge, these are the first parameterized intractability results for scheduling problems with few distinct processing times. Further, we show that 1 | s-batch (∞) , r j | ∑ w j U j is fixed-parameter tractable parameterized by # d + # p + # r , and parameterized by # d + # w if there is just a single release date. Both results hold even if the number of jobs per batch is limited by some integer b. [ABSTRACT FROM AUTHOR]

Investigations into the use of urease inhibitors for reducing ammonia emission in dairy farming have been published in several papers. The aim of this study is to expand the existing knowledge on the use of urease inhibitors for reducing ammonia emissions in fattening pig houses. In this respect, in addition to the proven standard application approach using a backpack sprayer, the investigation was extended to include different application techniques. Urease inhibitor was applied on two farms over six experimental periods throughout the year using three different application techniques: a backpack sprayer, and a semi-automatic system that applies the inhibitor both on-floor and under-floor. Two identical compartments, alternated between treatment and control, were used on each farm. A linear mixed model with repeated measurements was used to quantify the reduction effect of the urease inhibitor. The use of the backpack sprayer led to a reduction in ammonia emissions of 22.9% (standard error, SE: 4.9%). The on-floor application system reduced the emissions by 16.6% (SE: 4.9%), and the under-floor application system resulted in no significant reduction. The development of the semi-automatic application system can be considered beneficial for reducing emissions. However, further development and improvement of this application system is necessary for its widespread practical use, especially regarding the distribution accuracy of the application liquid, contamination issues, and the manual workload. In addition, the effects of the presence of the animals during the application process need to be investigated in more detail. • Investigation of different urease inhibitor application techniques in pig houses. • A 22,9% reduction in ammonia emissions was achieved with a backpack sprayer. • On-floor application system shows a comparable reduction in ammonia emissions. • Under-floor application system showed no significant ammonia emission reduction. [ABSTRACT FROM AUTHOR]

Routines are an essential aspect of innovation processes as all new ideas must be implemented into daily routines to work. Previously, public management theory has understood routines as barriers to innovation that constrain collaboration due to inertia. This study aims to introduce a new understanding of routines as a precondition for innovation processes. By employing organizational theory and public management theory, we investigate routines through the micro-processes involved. Based on findings from an ethnographic fieldwork study involving the introduction of at-home chemotherapy, we suggest a rethinking of the notion of routines by explicating intra- and inter-organizational interactions and value creation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Trolley bags have gained popularity among students, but there is limited research comparing them to backpack-style school bags. OBJECTIVE: This study aimed to compare how carrying a backpack versus a trolley bag affects the activity of trunk and lower limb muscles in secondary school students. METHODS: Electromyographic activity was measured in 25 students (13.4±1.1 years) as they walked on level ground and up/down stairs while carrying both types of bags. The activity of the gastrocnemius, tibialis anterior, semitendinosus, rectus femoris, lumbar erector spinae, and rectus abdominis muscles was assessed on both the dominant and non-dominant sides. RESULTS: The study found significantly reduced muscle activation in most of the targeted muscles when walking on level ground with the trolley bag and when going up/down stairs with the backpack. CONCLUSIONS: Lifting a trolley bag depends on the slope of the walking surface and is more efficient on level ground, while carrying a backpack is more efficient when going up and down stairs. Since it is not practical to switch bags when encountering stairs in schools, a bag with a mixed model design incorporating features of both trolley and backpack may be more beneficial and practical for students to use. Students, parents, and teachers should be aware of the injury risks associated with carrying different types of bags. [ABSTRACT FROM AUTHOR]

The complementarity knapsack problem (CKP) is a knapsack problem with real-valued variables and complementarity conditions between pairs of variables. We extend the polyhedral studies of de Farias et al. for CKP, by proposing three new families of cutting-planes that are obtained from a combinatorial concept known as pack. Sufficient conditions for these inequalities to be facet-defining, based on the new concept of a maximal switching pack , are also provided. Moreover, we answer positively a conjecture by de Farias et al. about the separation complexity of the inequalities introduced in their work, and propose efficient separation algorithms for our newly defined cutting-planes. [ABSTRACT FROM AUTHOR]

Pesticide application development has grown exponentially in recent decades thanks to the implementation of new technologies and improved quality of spray input application. Electrostatic technology for increasing deposition has proven to be a suitable tool under specific study conditions, such as when working with very small droplet sizes, with air assistance, or typically in greenhouse environments. However, its effectiveness in hydraulic spraying, as well as its application from a commercial point of view in agriculture, is still challenging. The aim of this study was to evaluate the performance of this technology by implementing a modified lance on a small commercial knapsack sprayer, equipped with a hydraulic nozzle providing a range of droplet size values (Dv50) from 136 μm to 386 μm in the pressure range between 2 and 6 bar. This setup allowed operation under normal conditions (disconnected electrostatic system: NES) or with the connected electrostatic system (ES), with both configurations being tested in this study. Liquid distribution profiling as well as qualitative and quantitative evaluation of deposition were carried out both under laboratory conditions and in tomato crops under greenhouse conditions. The results showed no differences between the ES and NES in terms of flow rate (L min−1) characterization or in the total accumulated volume collected with the vertical bench. The impact of the electrostatic system connection was clearly observed in laboratory trials, with total deposition increases of up to 66%. In field trials, this effect decreased in unexposed areas and in denser sections of the crop. However, the overall increase in deposition, mainly associated with the exposed side, continued to be significant. [ABSTRACT FROM AUTHOR]

• Contrasting colours were used to enhance e-scooter rider visibility for drivers. • Detection time was lower with contrasting colours on both the e-scooter and rider. • Conspicuity ratings were higher for e-scooters with contrasting aids than grey clothes. • Contrasting visibility aids can reduce accidents from poor e-scooter visibility. This study explores how different visibility aids of contrasting colours could enhance the e-scooter riders' conspicuity under daylight conditions. With the rise in popularity of shared e-scooter services, an increase in incidents involving e-scooter riders and motorized counterparts was noticed. 48 licensed drivers (mean age = 24.6 years) detected the e-scooter riders in the videos and images featuring a simulated urban road environment in daylight, while performing a secondary task (n-back). The time to detect standing and moving e-scooter riders and subjective conspicuity ratings were assessed in three visibility aid conditions: Control (grey clothes and grey backpack), Patterned Jacket (jacket and backpack with checkerboard black and yellow pattern) and Wheels-Backpack (yellow stripes on the e-scooter wheels and on a dark backpack). Improved detectability was observed for e-scooter riders in the Wheels-Backpack condition, resulting in a minimum 168 ms increase in detection time compared to other two conditions. In terms of conspicuity ratings, participants gave higher scores to riders wearing Wheels-Backpack and Patterned Jacket (6.02 and 6.31, respectively, on a Likert 10-point scale), with no significant difference between them. Detection from videos or images showed similar effects. For all of these analyses, Bonferroni post-hoc tests followed a Repeated-measures ANOVA. Distributing contrasting colours across the e-scooter and the rider enhanced their daylight conspicuity better than when contrasting colours were located on the riders' upper body. However, drivers did not realise that these two visibility aids were not equal in terms of conspicuity benefits. [ABSTRACT FROM AUTHOR]

Abstract Background Freshwater mussels are important keystone and indicator species of aquatic ecosystems. Recent advances in sensor technology facilitate applications to individually track mussels and to record and monitor their behavior and physiology. These approaches require the attachment of sensor devices as “backpacks” to the outer shell surface. The interpretation of such data makes it necessary to understand the influence of these attachments on the horizontal and vertical movement behaviors of freshwater mussels. Over a series of mesocosm experiments, this study systematically investigated the effects of three size- and wiring-specific variants of artificially attached backpacks on the horizontal and vertical movement behavior of Anodonta anatina. Results Across all experiments, equipping mussels with backpacks did not result in a significant influence on horizontal movement for any of the backpack variants. In contrast to this finding, the big backpacks with a high ratio between backpack volume and mussel length resulted in a significantly negative effect on vertical movement, indicating a potential for adverse effects of such devices on mussels, especially in natural settings. Conclusions The findings of this study show that assessing the effects of attached devices on mussels requires a species-specific evaluation of potential impacts on the endpoints of interest. Especially for vertical movement patterns, selection of the smallest available devices appears mandatory.

Background: Carrying backpacks is believed to contribute to the musculoskeletal problems in school children. Studies on the use of backpacks by Nigerian school children are scanty. Objectives: To evaluate the use of backpack and associated problems among primary school children. Methods: A cross-sectional descriptive study was carried out on 813 children in six primary schools in Ado-Ekiti. Information about backpack use and associated problems were obtained. Results: 788 (96.9%) children carried backpacks daily. The backpacks were all double strapped and 85% pupils wore them on both shoulders. The backpacks of 64.1% of the pupils contained educational materials. In 79.1% of cases, the backpacks exceeded 10% of their body weights. Pain and loss of sporting time were associated with carrying backpacks in 23.2% and 8.2% respectively, 15.3% took analgesic and 5.5% had medical consultations because of backpack injuries. No pupil missed school and none was hospitalised for backpack injury. Complaint of pain was significantly associated with older subjects, carrying heavier backpack and longer period of carrying packs (p

In 2009, Lyubashevsky proposed a lattice-based signature scheme using the Schnorr-like identification and the Fiat-Shamir heuristic and proved its security under the collision resistance of a generalized compact knapsack function. However, their security analysis requires the witness indistinguishability property, leading to significant inefficiency and an increase of sizes of public key and signature. To overcome the efficiency issue associated with the WI property, we introduce a new lattice-based assumption, called the target-modified one-wayness problem of the GCK function and show its reduction to well-known lattice-based problems. Additionally, we present a simple and efficient GCK-based signature scheme, GCKSign, whose security is based on the Module GCK-TMO problem in the random oracle model. GCKSign is a natural extension of Lyubashevsky's scheme in a module setting, but achieves considerable efficiency gains due to eliminating the witness indistinguishability property. As a result, GCKSign achieves approximately 3.4 times shorter signature size and 2.4 times shorter public key size at the same security level. [ABSTRACT FROM AUTHOR]

Background: Young students with skeletal immaturity report an increasing number of musculoskeletal symptoms associated with daily use of heavy backpacks. This cross-sectional study investigated the relationship between heavy backpack use and reports of pain. Methods: Data were collected from 300 students aged 11 to 18 at the University of Toronto Schools. Results: Students, on average, carried 15.9% of their body weight. 54% of students reported physiological complaints, primarily back, shoulder, neck, and leg pain. Backpack weight as a % of body weight was strongly associated with pain complaints. Younger students and those with longer commutes were more likely to report heavy backpacks (50% compared to 22.6% of older students, p< .001) and pain. Conclusion: Carrying heavy backpacks could result in increased musculoskeletal complaints in young students. Findings suggest that even the upper bound of currently recommended guidelines (20% of body weight) may be too high, especially for younger children. [ABSTRACT FROM AUTHOR]

A variant of the online knapsack problem is considered in the setting of predictions. In Unit Profit Knapsack, the items have unit profit, i.e., the goal is to pack as many items as possible. For Online Unit Profit Knapsack, the competitive ratio is unbounded. In contrast, it is easy to find an optimal solution offline: Pack as many of the smallest items as possible into the knapsack. The prediction available to the online algorithm is the average size of those smallest items that fit in the knapsack. For the prediction error in this hard online problem, we use the ratio r = a a ^ where a is the actual value for this average size and a ^ is the prediction. We give an algorithm which is e - 1 e -competitive, if r = 1 , and this is best possible among online algorithms knowing a and nothing else. More generally, the algorithm has a competitive ratio of e - 1 e r , if r ≤ 1 , and e - r e r , if 1 ≤ r < e . Any algorithm with a better competitive ratio for some r < 1 will have a worse competitive ratio for some r > 1 . To obtain a positive competitive ratio for all r, we adjust the algorithm, resulting in a competitive ratio of 1 2 r for r ≥ 1 and r 2 for r ≤ 1 . We show that improving the result for any r < 1 leads to a worse result for some r > 1 . [ABSTRACT FROM AUTHOR]

To accelerate the convergence rate of high-dimensional optimization problems, inspired by the cooperative hunting process of spider colonies named Anelosimus eximius, a new A. eximius colony algorithm (AECA) was proposed to solve combinatorial optimization problems. In the AECA, a certain direction component of the problem solution is represented as a certain direction in which a spider travels, so that a high-dimensional optimization problem can be transformed into multiple low-dimensional optimization problems. The AECA includes two intelligent behaviors: the random walk of spiders and the summoning of the initiator. The random walk of spiders ensures the diversity of spider colonies, whereas the summoning of the initiator can accelerate the convergence rate. We theoretically proved that the AECA is globally convergent. The inversion method of asteroid spectrum reflectance template can be used to solve the problem that the measured planetary spectrum is affected by the asteroid absorption effect and improves the accuracy of celestial Doppler difference velocimetry, which uses celestial spectrum to provide the information of velocity measurement for navigation. The essence of this method is the optimal combination problem of intrinsic mode functions (IMFs). We applied the AECA to the inversion of the planetary spectrum reflectance template. Experimental results show that, compared with genetic algorithms (GAs), the AECA can obtain the optimal combination of spectrum reflectance templates faster. In addition, to verify the universality of the AECA, for the classical knapsack problem, the AECA has a better optimization effect, faster convergence rate, and higher stability than other swarm intelligence algorithms such as GA, discrete particle swarm optimization, and the quantum genetic algorithm. [ABSTRACT FROM AUTHOR]

Background: The work-related motorcyclist is prone to driving-related issues due to the longer duration of riding positions and might not be aware of the improper posture they hold throughout the day and land up causing several problems There is a need for a posture corrector device which can help the motorcyclist maintain their proper posture and reduce pain. Objectives: The objective of the study was to assess the musculoskeletal pain in the motorcyclist, to assess the range of motion of the spinal and cervical joint and to evaluate the effectiveness of the customized backrest with post-assessment. Materials and Methods: An analytical study was done among motorcyclists working in Karad. Detailed assessment was taken with the VAS (visual analogue scale) and range of motion of the cervical and spine. Proper consent and ethical permission were taken, the prototype was given to the motorcyclist for use for 30 days and an assessment was done after the use of the backrest. Results: In our study, the participants experienced that the pain they had during riding and the musculoskeletal problems they had dure to improper posture while riding were reduced after the use of the customized device and was also supportive for the back and easy to use for daily need. Conclusion: We conclude that the effect of a backrest for the motorcyclist is a need of cause. The results observed after the use of the backrest were significant, the pain rating was reduced and the altered range of motion was also improved in post-assessment. [ABSTRACT FROM AUTHOR]

Background: Freshwater mussels are important keystone and indicator species of aquatic ecosystems. Recent advances in sensor technology facilitate applications to individually track mussels and to record and monitor their behavior and physiology. These approaches require the attachment of sensor devices as "backpacks" to the outer shell surface. The interpretation of such data makes it necessary to understand the influence of these attachments on the horizontal and vertical movement behaviors of freshwater mussels. Over a series of mesocosm experiments, this study systematically investigated the effects of three size- and wiring-specific variants of artificially attached backpacks on the horizontal and vertical movement behavior of Anodonta anatina. Results: Across all experiments, equipping mussels with backpacks did not result in a significant influence on horizontal movement for any of the backpack variants. In contrast to this finding, the big backpacks with a high ratio between backpack volume and mussel length resulted in a significantly negative effect on vertical movement, indicating a potential for adverse effects of such devices on mussels, especially in natural settings. Conclusions: The findings of this study show that assessing the effects of attached devices on mussels requires a species-specific evaluation of potential impacts on the endpoints of interest. Especially for vertical movement patterns, selection of the smallest available devices appears mandatory. [ABSTRACT FROM AUTHOR]

The multi-dimensional investor or backpack problem is an important and well-known difficult constrained combinatorial optimization problem in operations research and optimization. Nowadays, algorithms inspired by nature have become extremely important in solving many mathematical problems, including the investor’s portfolio problem. In order to reach the best solutions, this research reviewed the bat algorithm and the updates that occurred to it in solving this problem. [ABSTRACT FROM AUTHOR]

Teaching practices are moving from decontextualised to more representative curricula. Although this is argued to be a positive step, low motor competence is a continual issue in primary-aged school children. One methodological approach to investigate ways to improve motor competence, eye tracking, is moving to more representative tasks. So far, eye-tracking research using static activities has demonstrated a positive association between motor competence and earlier fixation and longer duration. However, this research has been constrained to laboratory settings and tasks, or discrete activities (e.g., throw and catch). This study seeks to understand how to conduct more representative eye-tracking research in primary school-aged children. To this end, thirteen 10–11-year-old children were fitted with an eye-tracker during a typical football coaching session. Children were asked acceptability-based questions, and eye-gaze data were captured to illustrate what children attended to under a representative dynamic football-based activity. Based on the voices of children and captured eye-gaze data, six practical implications for research in this population are proposed: (1) conduct eye-tracking research indoors (where possible); (2) ensure long hair or fringes are secured so as not to obscure line of sight; (3) run the same activity to increase comparability across children wearing the eye-tracker; (4) use a properly fitted backpack (if a backpack is to be used); (5) assure children about the capability and hardiness of the eye-tracker, as they do not need to change the way they move; (6) explain there may be some discomfort with the nose clip, head strap, and battery weight and ensure that children wish to continue. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Backpacks are a convenient means of carrying the load. Its continuous usage has led to severe shoulder injuries and back pain due to the dynamic forces exerted by the weight of the backpack on the shoulders of the wearer during running or walking. A traditional backpack moves up and down repeatedly with the shoulder of the wearer during walking or running. Such repetitive movements of the backpack cause discomfort and strain on the wearer's shoulders. Hence, a mechanism is proposed here that can be assembled with the normal backpack in a way that the backpack stays at a constant position with respect to the ground by moving it relative to the wearer. The proposed mechanism was designed, fabricated, and assembled with a normal backpack and checked for the impact force experienced by the wearer with different loads of 10 kg, 12.5 kg, and 15 kg. An Arduino-based setup with a load cell sensor was implemented into the mechanism to measure the impact forces exerted on the wearer's shoulder. The impact forces experienced by the wearer were found to be considerably lower when using the enhanced backpack with the mechanism compared to a normal backpack without the mechanism for a load equal to or more than 15 kg. [ABSTRACT FROM AUTHOR]

Emerging technologies, such as the fifth generation (5G) and the Internet of Things (IoT), increase the communication capabilities of components such as smart vehicles in intelligent transportation systems. Consequently, there is a demand for vehicular services to fulfil the purpose of safe driving and comfort in smart transportation and augmented reality assistants. These vehicular services are delay-sensitive tasks and computation-intensive tasks. Hence, these tasks are not ideal for vehicle processing due to stringent deadlines, finite resource constraints and the battery life of vehicles. Therefore, they are handled by offloading into roadside infrastructures (e.g., roadside units or high power nodes), called fog nodes (FNs), for further processing. However, when the delay-sensitive tasks increase in the network during peak time, the processing of such tasks in FNs poses a challenge regarding meeting deadlines and energy consumption. Therefore, we propose an energy and priority-aware scheduling (EPAS) algorithm to handle the delay-sensitive tasks in the overlap coverage areas of fog-enabled vehicular networks (FEVNs) such that the energy consumption of FNs is reduced while meeting deadlines. Task scheduling among FNs is a multiple 0/1 knapsack, a well-known nondeterministic polynomial (NP)-hard problem. Hence, the EPAS is a greedy-based sub-optimal solution to the task scheduling problem with a finite number of tasks and FNs in FEVNs. The performance of EPAS is evaluated by considering the peak arrival of tasks into the network. The simulation outcomes depict that the EPAS algorithm lowers the FN's energy consumption compared to benchmark algorithms. [ABSTRACT FROM AUTHOR]

The aim of the research presented in the article is to use the Metalog family of probability distributions to assess the technical condition of traction battery packs from electric and hybrid vehicles. The description of the research object, which is a battery pack from a hybrid vehicle, will be provided. Then, a system for controlled charging and discharging of individual cells in a battery pack will be reviewed. It is an essential diagnostic and research device used to determine the capacity of individual cells. The capacity values of all battery cells will then be analyzed using the Metalog probability distribution family. The use of this tool allows us to determine the Probability Density Function for the entire battery pack. Based on this, the diagnostician is able to assess the technical condition of the tested package and decide on its further fate. It can be intended for repair, employed as a stationary energy storage facility, or used for disposal. The algorithm for assessing the technical condition of traction batteries proposed by the authors can be used in all battery packs regardless of the type of cells used and their energy capacity. [ABSTRACT FROM AUTHOR]

This paper investigates the correlation between a pilot's brain electroencephalographic (EEG) activity and his driving posture, addressing the intricate relationship between cognition and behavior in aviation. We designed and implemented a simulated experiment that recorded the fly pilot's attitude and collected EEG information as experimental data. The experiment is only based on EEG data to predict flight posture (pull, down, left, right). We propose a flight-driving attitude prediction model (CA-FAP) based on CEBRA and self-attention mechanism, with a prediction accuracy of 0.83. This model is better than common spatial pattern (CSP) and uniform manifold approximation and projection (UMAP) dimension reduction methods in the experiment. Moreover, a better effect can be obtained in the larger attitude radian dataset (accuracy is 0.85), and the effect is not obvious in the dataset of closing the six-axis motion platform, indicating that the model prediction of flight attitude is closely related to the pilot position transformation. By comparing the prediction effect of each category, the pull-up and drop are better than the steering prediction result. The study can help pilots adjust their posture and decisions, and serve as a basis for studying flight pilot cognitive load, mental load, mood changes, and flight performance. [ABSTRACT FROM AUTHOR]

To improve water access while working and contribute to fewer heat-related illnesses (HRI), backpack hydration systems were provided to over 200 farmworkers to use during the 2022 growing season. Acceptability of the water intake intervention was assessed among farmworkers in eastern North Carolina, USA. With a pre-established community–university partnership, the acceptability of the intervention was assessed using a cross-sectional survey. The backpack brand selected included a 3-liter water bladder and attached drinking hose. Data analysis included descriptive and correlation statistics. Among 47 male, migrant farmworkers, most (90%) reported the hydration backpack to be acceptable or completely acceptable to workplace fluid intake. Most (53%) reported using the backpack some of the time, compared to 28% who used it often. The participants reported an average of 4.8 (SD 2.2) liters of water intake from the backpack on a typical workday. Most reported the backpack improved the quantity and frequency of their water consumption. This study was an important first step in implementation of hydration backpack systems as an HRI-preventative intervention among farmworkers. Future interventional studies could assess the efficacy of the backpacks on health outcomes, including incidence of dehydration and symptoms of HRI. [ABSTRACT FROM AUTHOR]

We close three open problems on the separation complexity of valid inequalities for the knapsack polytope. Specifically, we establish that the separation problems for extended cover inequalities, (1, k)-configuration inequalities, and weight inequalities are all N P -complete. We also show that, when the number of constraints of the LP relaxation is constant and its optimal solution is an extreme point, then the separation problems of both extended cover inequalities and weight inequalities can be solved in polynomial time. Moreover, we provide a natural generalization of (1, k)-configuration inequality which is easier to separate and contains the original (1, k)-configuration inequality as a strict sub-family. [ABSTRACT FROM AUTHOR]

The urban three-dimensional (3-D) model, which can truly and vividly express the 3-D spatial information of ground objects, was an essential link in the process of smart city construction. The backpack 3-D laser scanning systems had gradually become an important technical means to build urban 3-D models because of their high efficiency and high fineness. In this paper, the error source of backpack point cloud data was analysed based on the composition of backpack 3-D laser scanning system. The distribution of point cloud error was statistically analysed by designing experiments. It was found that there was a systematic error in the backpack 3-D laser scanning point cloud. There were many factors influencing the system errors and they were superimposed on each other. In order to solve this problem, an error compensation model with additional system parameters based on a multiple linear regression algorithm was constructed. The results showed that this model can weaken the influence of system errors on the backpack point cloud, effectively improve the accuracy of the backpack point cloud, and provide reliable point cloud data for subsequent processing of the building point cloud. [ABSTRACT FROM AUTHOR]

Due to the unique conditions of the Wudong subvertical coal seam, damage to the underground roadway occurs frequently during the coal mining process. With the increase in mining depth, the energy and incidence of microseismic events increase significantly, showing characteristics of zoning and grading along the strike. Therefore, the damage to the underground roadway of the Wudong coal seam was studied with a focus on dynamic load disturbance. The results showed that the underground roadway damage exhibits asymmetric characteristics, with significant sinking on the north shoulder and various degrees of bulging on both sides of the roadway. The existing support scheme in the mine could not effectively control the deformation and damage to the rock surrounding the underground roadway under the action of dynamic loads. Therefore, the asymmetric support scheme with the high prestressed anchoring long and short anchor cable network was proposed to provide targeted reinforcement for the underground roadway, which has been shown to effectively mitigate the deformation of the surrounding rock. Eventually, considering the characteristics of microseismic event distribution and the observed increase in the rock damage with the increase of the seismic source energy, a segmented and asymmetric support scheme was suggested to tactically support the underground roadway. The findings of this study could potentially improve the ground safety of underground roadways under similar mining conditions. [ABSTRACT FROM AUTHOR]

The optimization of Multidimensional Knapsacks with Family‐Split Penalties has been introduced in the literature as a variant of the more classical Multidimensional Knapsack and Multi‐Knapsack problems. This problem deals with a set of items partitioned in families, and when a single item is picked to maximize the utility, then all items in its family must be picked. Items from the same family can be assigned to different knapsacks, and in this situation split penalties are paid. This problem arises in real applications in various fields. This paper proposes a new exact and fast algorithm based on a specific Combinatorial Benders Cuts scheme. An extensive experimental campaign computationally shows the validity of the proposed method and its superior performance compared to both commercial solvers and state‐of‐the‐art approaches. The paper also addresses algorithmic flexibility and scalability issues, investigates challenging cases, and analyzes the impact of problem parameters on the algorithm behavior. Moreover, it shows the applicability of the proposed approach to a wider class of realistic problems, including fixed costs related to each knapsack utilization. Finally, further possible research directions are considered. [ABSTRACT FROM AUTHOR]

The results of traditional vegetation-measuring methods are mostly two-dimensional data, which can only convey limited information. The greening situation of many cities or regions in the world cannot be fully assessed by these results. In this regard, this paper proposes the use of the air–ground integrated point cloud data acquisition mode for measuring vegetation. This mode combines a backpack-mounted laser scanning system, a vehicle-mounted laser scanning system, and UAV tilt photography technology to collect greening data in a comprehensive park and along a municipal road in Guangzhou, China. To classify the collected greening data, we propose the BiFPN-KPointNet-CBAM model, which was derived from PointNet. The model was introduced to analyze the distribution of green plants in study areas. The experimental findings indicate that our model achieved a notable enhancement in the overall accuracy by approximately 8% compared with other state-of-the-art models. Compared with the traditional greening survey method, this method obtained three-dimensional and more accurate greening data, and thus, provides higher quality greening data for urban managers. [ABSTRACT FROM AUTHOR]

In this paper, we address the difficulty of solving large-scale multi-dimensional knapsack instances (MKP), presenting a novel deep reinforcement learning (DRL) framework. In this DRL framework, we train different agents compatible with a discrete action space for sequential decision-making while still satisfying any resource constraint of the MKP. This novel framework incorporates the decision variable values in the 2D DRL where the agent is responsible for assigning a value of 1 or 0 to each of the variables. To the best of our knowledge, this is the first DRL model of its kind in which a 2D environment is formulated, and an element of the DRL solution matrix represents an item of the MKP. Our framework is configured to solve MKP instances of different dimensions and distributions. We propose a K-means approach to obtain an initial feasible solution that is used to train the DRL agent. We train four different agents in our framework and present the results comparing each of them with the CPLEX commercial solver. The results show that our agents can learn and generalize over instances with different sizes and distributions. Our DRL framework shows that it can solve medium-sized instances at least 45 times faster in CPU solution time and at least 10 times faster for large instances, with a maximum solution gap of 0.28% compared to the performance of CPLEX. Furthermore, at least 95% of the items are predicted in line with the CPLEX solution. Computations with DRL also provide a better optimality gap with respect to state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

Using backpacks causes many problems for the body and has a negative impact on the user. Continuous use of a backpack will cause irreversible changes to the user. The heavy load on a backpack doesn't just have an impact on shoulder pain. Analytical observational method with a cross-sectional approach, the research was carried out by weighing the bag, distributing questionnaires to assess the length of time the bag was used and age, and measuring the position of the right and left shoulders using a measuring scale. Results; bag weighing ± 3.52 kg with a minimum bag weight of 1.90 kg and a maximum of 7.6 kg. using the bag on average ±27.25 minutes, with a minimum time of 5 minutes and a maximum time of 120 minutes. The average left shoulder posture is ± 124.28, the minimum value is 108 and the maximum value is 145. The average right shoulder posture is ± 123.50, the minimum value is 107 and the maximum value is 141. Conclusion; there is no relationship between the weight of the bag used by the respondent and the posture of the respondent's right shoulder, as evidenced by the resulting significance value of 0.607

We consider Bandits with Knapsacks (henceforth, BwK), a general model for multi-armed bandits under supply/budget constraints. In particular, a bandit algorithm needs to solve a well-known knapsack problem: find an optimal packing of items into a limited-size knapsack. The BwK problem is a common generalization of numerous motivating examples, which range from dynamic pricing to repeated auctions to dynamic ad allocation to network routing and scheduling.While the priorwork on BwK focused on the stochastic version, we pioneer the other extreme in which the outcomes can be chosen adversarially. This is a considerably harder problem, compared to both the stochastic version and the “classic” adversarial bandits, in that regret minimization is no longer feasible. Instead, the objective is to minimize the competitive ratio: the ratio of the benchmark reward to algorithm’s reward. We design an algorithm with competitive ratio O(logT ) relative to the best fixed distribution over actions, whereT is the time horizon; we also prove a matching lower bound. The key conceptual contribution is a new perspective on the stochastic version of the problem. We suggest a new algorithm for the stochastic version, which builds on the framework of regret minimization in repeated games and admits a substantially simpler analysis compared to prior work. We then analyze this algorithm for the adversarial version, and use it as a subroutine to solve the latter. Our algorithm is the first “black-box reduction” frombandits to BwK: it takes an arbitrary bandit algorithm and uses it as a subroutine. We use this reduction to derive several extensions. [ABSTRACT FROM AUTHOR]

Nowadays, what captures consumers' primary attention is how to purchase electric vehicles with long range and desirable price. Lightweight construction stands as one of the most effective approaches for prolonging range and lowering costs. As a consequence, it is particularly imperative to undertake lightweight design optimization for the battery bracket of new energy vehicles by applying 3D printing technology. To actualize this goal, Rhino software was initially employed for 3D modeling to design the battery bracket system for a pure electric vehicle in China. Subsequently, topology optimization design of the battery bracket was carried out by adopting Altair Inspire software. Last but not least, manufacturing and assembly inspection were completed using a 3D printer. The results show that the maximum displacement of the battery lower tray bracket after topology optimization is 3.20 mm, which is slightly higher than before, but still relatively small. The maximum Mises equivalent stress rose to 240.7 MPa post-optimization, but brought about a uniform stress distribution at the bottom of the bracket. In comparison, the minimum factor of safety met design requirements at 1. The mass was lessened to 0.348 kg, representing a 49.2% decrease in comparison with pre-optimization levels. The 3D-printed bracket was fabricated by employing a 3D printer, thereby achieving the aforementioned mass abatement. The battery pack parts exhibited a bright surface with low roughness and no discernible warping or deformation defects. As revealed by the assembly results, the components of the battery pack bracket are tightly coordinated with each other, with no evident assembly conflicts, revealing that the dimensional accuracy and fit of the completed parts meet production requirements. These findings lay solid groundwork for the mass production of high-performance battery pack brackets. [ABSTRACT FROM AUTHOR]

The present study aims to optimize the structural design of a Z-type flow lithium-ion battery pack with a forced air-cooling system known as BTMS (battery thermal management system). The main goal is to minimize Tmax (maximum temperature) and ΔTmax (maximum temperature difference) while ensuring an even airflow distribution within the battery module. The present study thoroughly investigates critical factors, such as the inlet air velocity, tapered inlet manifold, and the number of secondary outlets, to evaluate their impact on thermal performance and airflow uniformity within the battery module. Increasing the inlet air velocity from 3 to 4.5 m/s significantly improves the thermal cooling performance of the BTMS, resulting in a decrease of 4.57 °C (10.05%) in Tmax and 0.29 °C (9.79%) in ΔTmax compared to the original 3 m/s velocity. Further, the study assesses the significance of a tapered inlet manifold as a critical factor, revealing its substantial impact on cooling performance and temperature reductions in battery cells 3–9. It also facilitates a more uniform airflow distribution, decreasing the velocity difference between channel 9 and channel 1 from 3.32 to 2.50 m/s. Incorporating seven secondary outlets significantly improves the heat dissipation ability of the BTMS, resulting in a decrease of 0.894 °C (2.18%) in Tmax and 2.23 °C (72.84%) in ΔTmax compared to the configuration with 0 secondary outlets. By optimizing these parameters, the aim is to enhance BTMS's capabilities, improving LIB (lithium-ion battery) packs' performance and reliability. The optimized structural design parameters proposed in this study yield practical applications that extend beyond theoretical insights, impacting diverse fields reliant on lithium-ion battery technology. Through enhanced thermal management systems, applications in electric vehicles and portable electronics are poised to experience improved performance and longevity. Furthermore, these advancements inform the development of next-generation battery packs, promising reduced overheating risks and extended battery life. Such innovations are critical in energy storage systems for renewable energy applications and electric vehicle technology, facilitating faster charging times and increased driving range. Moreover, the implications extend to aerospace applications, ensuring the reliability of batteries in extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Recent advances in sensor and algorithmic technologies have led to the exploration of remote/proximal sensing for automated forest inventory at various scales. For detailed below-canopy mapping to derive critical forest biometrics, such as diameter at breast height (DBH), merchantable height, and debris volume, under-canopy mobile LiDAR mapping is preferred. These mapping systems typically rely on an onboard integrated global navigation satellite system/inertial navigation system (GNSS/INS) unit for point cloud generation. The main challenge of such under-canopy mapping is the intermittent access to the GNSS signal, which is crucial to deriving accurately georeferenced mapping products. Advances in Simultaneous Localization and Mapping (SLAM) offer an alternative to GNSS/INS-assisted georeferencing in GNSS-denied/challenging scenarios. In this study, we propose a general and comprehensive Forest Feature LiDAR SLAM framework that encompasses odometry and mapping threads for a 3D LiDAR unit mounted on backpack systems to achieve accurate forest inventories. In the odometry thread, ground/tree trunk features are extracted from LiDAR scans (i.e., points from a full revolution of the laser beams) and used to estimate the transformation between successive scans. The mapping thread performs local/global least squares adjustment (LSA) using derived features to register LiDAR scans to a common reference frame. One advantage of the proposed framework is that the tree trunk features and ground information – which are critical to forest inventory applications – are directly derived in the SLAM process, making it superior to other geometric feature-based approaches. Additionally, relative trajectory information provided by onboard navigation units and/or reference point clouds from other sources can be incorporated into the process. In this study, three in-house developed backpack systems with varying specifications were used to collect data in complex forest areas. The proposed SLAM strategy was performed on these datasets and compared with point clouds acquired by uncrewed aerial vehicle (UAV) and a commercial backpack LiDAR system. Experimental results suggested that the proposed framework can produce point clouds with satisfactory intra-dataset alignment quality (in the range of 2–4 cm) and positional accuracy (around 10 cm) for all backpack systems. [ABSTRACT FROM AUTHOR]

Background: The promotion of cycling for children is beneficial from a health and environmental perspective, however road safety and awareness amongst this age group remain a considerable issue. As children are developing their cognitive and physical abilities, they are considered a high-risk group for injuries and fatalities on the roads. Virtual learning environments have demonstrated promising ways to engage children in learning about road risks and teach children about safe cycling. Intervention: A web-based Virtual Learning Environment (VLE) and Virtual Reality (VR) environment was designed to offer a platform for schoolchildren to learn about safe cycling and to develop skills for them to better detect hazards in traffic. Both learning environments were used by 455 school children and 20 class teachers. Methods: Fun toolkit methods, specifically designed for child participants were used to assess the design of the technology, and for teachers a qualitative survey to provide evidence around the use of both learning environments. Results: Results suggest both learning environments were appealing for lower school grade participants. For grades five and six a need to review the relevance and user design of the learning content was evident. The VR environment was highly attractive across all school grades, suggesting that VR could be a feasible way to teach road safety and safe cycling for school children. Discussion: Although VLE and VR environment were attractive and fun to use, some users of VR experienced motion sickness. This would need to be considered and further examined before engaging a young learner in a VR learning environment. Several considerations are provided for teachers, practitioners, researchers, and designers seeking means to promote safe cycling for children. [ABSTRACT FROM AUTHOR]

The Multi-Objective Mixed-Integer Programming (MOMIP) problem is one of the most challenging. To derive its Pareto optimal solutions one can use the well-known Chebyshev scalarization and Mixed-Integer Programming (MIP) solvers. However, for a large-scale instance of the MOMIP problem, its scalarization may not be solved to optimality, even by state-of-the-art optimization packages, within the time limit imposed on optimization. If a MIP solver cannot derive the optimal solution within the assumed time limit, it provides the optimality gap, which gauges the quality of the approximate solution. However, for the MOMIP case, no information is provided on the lower and upper bounds of the components of the Pareto optimal outcome. For the MOMIP problem with two and three objective functions, an algorithm is proposed to provide the so-called interval representation of the Pareto optimal outcome designated by the weighting vector when there is a time limit on solving the Chebyshev scalarization. Such interval representations can be used to navigate on the Pareto front. The results of several numerical experiments on selected large-scale instances of the multi-objective multidimensional 0–1 knapsack problem illustrate the proposed approach. The limitations and possible enhancements of the proposed method are also discussed. [ABSTRACT FROM AUTHOR]

The security of communication networks can be compromised through both known and novel attack methods. Protection against such attacks may be achieved through the use of an intrusion detection system (IDS), which can be designed by training machine learning models to detect cyberattacks. In this paper, the KOMIG (knapsack optimization and mutual information gain) IDS was developed to detect network intrusions. The KOMIG IDS combined the strengths of optimization and machine learning together to achieve a high intrusion detection performance. Specifically, KOMIG IDS comprises a 2-stage feature selection procedure; the first was accomplished with a knapsack optimization algorithm and the second with a mutual information gain filter. In particular, we developed an optimization model for the selection of the most important features from a network intrusion dataset. Then, a new set of features was synthesized from the selected features and combined with the selected features to form a candidate features set. Next, we applied an information gain filter to the candidate features set to prune out redundant features, leaving only the features that possess the maximum information gain, which were used to train machine learning models. The proposed KOMIG IDS was applied to the UNSW-NB15 dataset, which is a well-known network intrusion evaluation dataset, and the resulting data, after optimization operation, were used to train four machine learning models, namely, logistic regression (LR), random forest (RF), decision tree (DT), and K-nearest neighbors (KNN). Simulation experiments were conducted, and the results revealed that our proposed KNN-based KOMIG IDS outperformed comparative schemes by achieving an accuracy score of 97.14%, a recall score of 99.46%, a precision score of 95.53%, and an F1 score of 97.46%. [ABSTRACT FROM AUTHOR]

Obesity is a systemic and chronic inflammation, which seriously endangers people's health. People tend to diet to control weight, and the short-term effect of dieting in losing weight is significant, but the prognosis is limited. With weight loss and recovery occurring frequently, people focus on weight cycling. The effect of weight cycling on a certain tissue of the body also has different conclusions. Therefore, this article systematically reviews the effects of body weight cycling on the body and finds that multiple weight cycling (1) increased fat deposition in central areas, lean mass decreased in weight loss period, and fat mass increased in weight recovery period, which harms body composition and skeletal muscle mass; (2) enhanced the inflammatory response of adipose tissue, macrophages infiltrated into adipose tissue, and increased the production of pro-inflammatory mediators in adipocytes; (3) blood glucose concentration mutation and hyperinsulinemia caused the increase or decrease in pancreatic β-cell population, which makes β-cell fatigue and leads to β-cell failure; (4) resulted in additional burden on the cardiovascular system because of cardiovascular rick escalation. Physical activity combined with calorie restriction can effectively reduce metabolic disease and chronic inflammation, alleviating the adverse effects of weight cycling on the body. [ABSTRACT FROM AUTHOR]

Waste management is one of the many major challenges faced by all urban cities around the world. With the increase in population, the current mechanisms for waste collection and disposal are under strain. The waste management problem is a global challenge that requires a collaborative effort from different stakeholders. Moreover, there is a need to develop technology-based solutions besides engaging the communities and establishing novel policies. While there are several challenges in waste management, the collection of waste using the current infrastructure is among the top challenges. Waste management suffers from issues such as a limited number of collection trucks, different types of household and industrial waste, and a low number of dumping points. The focus of this paper is on utilizing the available waste collection transportation capacity to efficiently dispose of the waste in a time-efficient manner while maximizing toxic waste disposal. A novel knapsack-based technique is proposed that fills the collection trucks with waste bins from different geographic locations by taking into account the amount of waste and toxicity in the bins using IoT sensors. Using the Knapsack technique, the collection trucks are loaded with waste bins up to their carrying capacity while maximizing their toxicity. The proposed model was implemented in MATLAB, and detailed simulation results show that the proposed technique outperforms other waste collection approaches. In particular, the amount of high-priority toxic waste collection was improved up to 47% using the proposed technique. Furthermore, the number of waste collection visits is reduced in the proposed scheme as compared to the conventional method, resulting in the recovery of the equipment cost in less than a year. [ABSTRACT FROM AUTHOR]

To better understand how vocalisations are used during interactions of multiple individuals, studies are increasingly deploying on‐board devices with a microphone on each animal. The resulting recordings are extremely challenging to analyse, since microphone clocks drift non‐linearly and record the vocalisations of non‐focal individuals as well as noise. Here we address this issue with callsync, an R package designed to align recordings, detect and assign vocalisations to the caller, trace the fundamental frequency, filter out noise and perform basic analysis on the resulting clips. We present a case study where the pipeline is used on a dataset of six captive cockatiels (Nymphicus hollandicus) wearing backpack microphones. Recordings initially had a drift of ~2 min, but were aligned to within ~2 s with our package. Using callsync, we detected and assigned 2101 calls across three multi‐hour recording sessions. Two had loud beep markers in the background designed to help the manual alignment process. One contained no obvious markers, in order to demonstrate that markers were not necessary to obtain optimal alignment. We then used a function that traces the fundamental frequency and applied spectrographic cross correlation to show a possible analytical pipeline where vocal similarity is visually assessed. The callsync package can be used to go from raw recordings to a clean dataset of features. The package is designed to be modular and allows users to replace functions as they wish. We also discuss the challenges that might be faced in each step and how the available literature can provide alternatives for each step. [ABSTRACT FROM AUTHOR]

In the railway industry, there is ongoing research on incorporating large-capacity energy storage system (ESS) into railway vehicles to reduce carbon emissions and enhance energy efficiency. Lithium-ion batteries are widely used in ESSs due to their high energy density. However, their high chemical reactivity can lead to a higher risk of malfunction. This compromises the reliability of railway vehicles using a high-capacity ESS as a propulsion power source. This study aims to improve the reliability of the battery packs used in railway vehicles by introducing a novel circuit configuration that integrates a bypass circuit into the traditional redundant circuit configuration used in lithium batteries. In conventional ESS systems, an additional battery pack needs to be equipped to sustain normal operation in the case of a battery malfunction event. However, this leads to a substantial increase in the volume and weight of the ESS. The circuit configuration proposed in this paper guarantees the normal operation of the ESS in the case of a battery failure using a few additional circuit components. The feasibility of the proposed circuit configuration and its operation are examined using railway vehicle battery pack specifications. [ABSTRACT FROM AUTHOR]

To solve the high heat dissipation problem of lithium ion battery, the air‐cooled heat dissipation with fins is adopted for the thermal management. Heat dissipation characteristics of two types of air inlets and outlets (single air inlet and outlet, and double air inlet and outlet) and two types of surfaces (smooth and fin structure) were simulated and compared. When the air inlet and outlet are single inlet and single outlet, compared with smooth battery packs, finned construction packs can increase the Nusselt number by 24.9%. When the air inlet and outlet are double inlet and double outlet, compared with smooth battery packs, finned construction packs can increase the Nusselt number by 13.3%. The double‐air inlet and outlet battery pack can significantly reduce the average temperature of the battery pack compared with the single‐air inlet and outlet battery pack. Compared with the single‐inlet and single‐outlet solar smooth battery pack, it can increase the Nu by 131.6%, and the comprehensive performance index can reach 1.66. [ABSTRACT FROM AUTHOR]