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Impact of the administration type for normobaric hypoxia on the maximal aerobic capacity:A systematic review and meta-analysis
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作者 Sergio Pérez-Regalado Cristina Benavente +1 位作者 Filipa Almeida Belén Feriche 《Sports Medicine and Health Science》 2026年第2期153-162,共10页
Purpose: Normobaric hypoxia(NH) is a frequent strategy for training under hypoxic conditions that can be administered through different equipment, including face masks or hypoxic chambers/tents. Nonetheless, the versa... Purpose: Normobaric hypoxia(NH) is a frequent strategy for training under hypoxic conditions that can be administered through different equipment, including face masks or hypoxic chambers/tents. Nonetheless, the versatility of administration methods may influence the outcomes.Methods: Web of Science, Scopus, SPORTDiscus and Pub Med/MEDLINE were searched to identify studies assessing the effect of NH administered by face mask or chamber/tent equipment on maximal oxygen uptake( VO2max) after a training period. An overall meta-analysis and sub-analysis of total program session volume(low, moderate, high), participants' training level(trained, active, sedentary), and the severity of hypoxia(moderate, severe) were conducted to explore the effects of the NH-administration system.Results: Eighteen studies were included. Compared with normoxia, NH showed a moderate global improvement in VO2max(standardized mean difference [SMD] = 0.74;p = 0.06), favoring the chamber/tent(SMD = 1.30;p< 0.01) over the face mask. Sub-analysis showed a very large effect in support of the hypoxic chamber/tent among sedentary individuals and training programs with a high volume of sessions. Severe hypoxia did not yield conclusive findings in VO2max improvements, although the chamber/tent proved more effective(SMD = 1.42;p< 0.01) than the face mask under moderate hypoxia.Conclusions: Chambers/tents may slightly accentuate the benefit of NH on aerobic performance, particularly in participants with limited training experience following a high volume of sessions under moderate hypoxia.However, the variability of sub-analysis factors(session volume, participants' training level, and methodological approaches) between studies using each type of hypoxia-generating equipment may influence this result. 展开更多
关键词 Environmental physiology Exercise testing HYPOXIA Hypoxic systems Sports performance
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Radar Beampattern Gain Maximization for MIMO Integrated Sensing and Communication Systems
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作者 Ren Hong Zhang Ruoyu +2 位作者 Chen Guangyi Lin Xu Wu Wen 《China Communications》 2026年第2期268-284,共17页
Integrated sensing and communication(ISAC)is an appealing approach to address spectrum congestion and beamforming is an effective method to realize ISAC.In this paper,we investigate the beamforming design problem for ... Integrated sensing and communication(ISAC)is an appealing approach to address spectrum congestion and beamforming is an effective method to realize ISAC.In this paper,we investigate the beamforming design problem for multiple-input multipleoutput(MIMO)ISAC systems and propose to maximize the radar beampattern gain of the target direction while ensuring the signal-to-interference-plus-noise ratio(SINR)constraints of communication users.Particularly,we discuss two cases of ISAC transmit beamforming,i.e.,Case-Ⅰand Case-Ⅱ,which do not have and do have the dedicated probing signal,respectively.For these two cases of transmit beamforming design problems,we start from the single-user scenario and provide the closed-form solutions for MIMO ISAC beamforming vectors.Then,we consider the multiuser scenario and utilize the semidefinite relaxation technique to convert the beamforming design problems into convex semidefinite programming problems.Furthermore,we investigate the impact of the channel correlation between radar and communication on the performance gain of MIMO ISAC systems and characterize the performance tradeoff.Numerical results validate that the dedicated probing signal is unnecessary in the single-user scenario,whereas it has a slight improvement in target detection performance at low SINR thresholds in the multi-user scenario.It is also shown that the stronger the correlation between radar and communication channels,the greater the performance gain of the system. 展开更多
关键词 integrated sensing and communication multiple-input multiple-output performance tradeoff radar beampattern gain semidefinite relaxation
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Environmental Sustainability through Waste-to-Wealth Automotive Oil Usage in a Thermal Storage System Integrated with Circulating-Air Solar Air Heater
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作者 Shaymaa Husham Abdulmalek Ali Ahmed Gitan +2 位作者 Israa Sami Farhan Oras Fadhil Khalaf Sayf Waleed Albayati 《Energy Engineering》 2026年第3期117-131,共15页
The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heat... The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heater(SAH)integrated with an internal thermal storage unit using Waste Automotive Oil(WAO).The SAH was designed based on the circulation of confined air around the internal thermal storage unit due to the updraft effects of hot air.Two SAHs were tested to compare the performance of WAO and water,with the results being compared to previous work that utilised phase change material.Results showed that WAO responds faster in the early stage,while water has slightly higher daytime efficiency,with a maximum temperature of 60℃,while WAO reached a maximum temperature of 76℃.During the discharge cycle,WAO achieved an efficiency of 65.7%,while the water’s efficiency 73.2% within the same period.The highest outlet air temperatures recorded were 43℃ for WAO and 33.8℃ for water.These findings support that water is suitable for applications requiring rapid thermal charging,while WAO offers extended thermal stability.The study highlights the feasibility of using low-cost materials,such as WAO and water,to enhance the performance of solar energy systems,thereby making them more viable for industrial applications like drying and heating. 展开更多
关键词 Solar air heater phase change materials(PCM) thermal performance thermal storage waste oil
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The Income Security System in Japanese Traditional Performing Arts: A Strategy for Utilizing the Nation's Traditional Arts Resources
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作者 Tadashi Yagi Chisako Takashima Yoshinori Usui 《Journal of Modern Accounting and Auditing》 2013年第5期697-710,共14页
The objective of this paper is to examine an effective strategy for maintaining and utilizing the traditional arts resources of Japan. The authors explore two pillars of the strategy. One is to improve the quality of ... The objective of this paper is to examine an effective strategy for maintaining and utilizing the traditional arts resources of Japan. The authors explore two pillars of the strategy. One is to improve the quality of Japanese traditional performing arts by securing incomes for artists. The other is to utilize the traditional arts as a medium to expand Japanese cultural influence in foreign countries and to improve Japan's branding as a nation. First, the authors focus on the income security system practiced in traditional Japanese music and describe the discrepancy between short- and long-run optimality. The authors prove that the reputation of this art form affects its popularity and that it is optimal for the Iemoto (the head of the music school) to restrict the number of pupils in onstage performances in order to maintain stage quality. Second, the authors provide evidence that effective methods for a country to expand its cultural influence across the world differ among nations. The authors conduct willingness-to-pay (WTP) experiments and find that while German audiences largely prefer traditional Japanese music, those in the USA are slightly partial to its mixed fusion form. Therefore, the effective ways to expand Japanese cultural influence in foreign countries differ from one country to another. 展开更多
关键词 traditional performing arts the Iemoto system income security system stage quality cultural influence national branding
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An Improved Repetitive-Control System Using a Complex-Coefficient Filter 被引量:1
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作者 Qicheng Mei Jinhua She +1 位作者 Fei Long Yanjun Shen 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期282-284,共3页
Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter us... Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter used in the conventional repetitive controller(CRC), the complex-coefficient filter causes less change in the phase and amplitude of a signal at the frequencies of the periodic signal, especially at the fundamental frequency, when the two filters have the same cutofffrequency. 展开更多
关键词 improved repetitive controller irc periodic signals repetitive control system complex coefficient filter tracking performance conventional repetitive controller crc periodic signal enhance tracking performance
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Enhanced solid-electrolyte interface efficiency for practically viable hydrogen-air fuel cell systems 被引量:1
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作者 Venkitesan Sakthivel Dong Jin Yoo 《Journal of Energy Chemistry》 2025年第1期356-368,共13页
Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall performance.Currently,sulfonated poly(1,4-phenylene... Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall performance.Currently,sulfonated poly(1,4-phenylene ether-ether sulfone)(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion polymers.However,the long-term durability and stability of SPEES present a significant challenge.In this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate (A–Fe_(2)TiO_(5)),which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in PEMFCs.The modified SPEES/A–Fe_(2)TiO_(5)composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative stability.Notably,the SPEES membrane loaded with 1.2 wt%of A–Fe_(2)TiO_(5)demonstrates a maximum proton conductivity of 155 mS ccm^(-1),a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity (RH).Furthermore,the 1.2 wt%of A–Fe_(2)TiO_(5)/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm^(-2)and a current density of 1148 mA cm^(-2)at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous operation.This study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications. 展开更多
关键词 ACID-BASE Hybrid membrane Proton conductivity Polymer electrolyte fuel cell Single-cell performance
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Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach 被引量:1
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作者 Yi Huang Guo-Ping Liu +1 位作者 Yi Yu Wenshan Hu 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期478-480,共3页
Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectiv... Dear Editor,In this letter,a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated(HOFA)systems with noises.The method can effectively deal with nonlinearities,constraints,and noises in the system,optimize the performance metric,and present an upper bound on the stable output of the system. 展开更多
关键词 optimal control problem constrained networked predictive control strategy Performance Optimization present upper bound Nonlinear systems NOISES Constrained Networked Predictive Control High Order Fully Actuated systems
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Preparation and performance evaluation of sand consolidation and water blocking system for loose sandstone reservoir
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作者 Zhiwei Huang Yongqian Jian +1 位作者 Mingqiang Zhou Jinlong Liu 《日用化学工业(中英文)》 北大核心 2025年第11期1395-1401,共7页
Sand production and high water content in oil wells are two major challenges that restrict high and stable production in loose sandstone reservoirs.In this paper,nano SiO_(2),coupling agent triethoxysilane,phenolic re... Sand production and high water content in oil wells are two major challenges that restrict high and stable production in loose sandstone reservoirs.In this paper,nano SiO_(2),coupling agent triethoxysilane,phenolic resin and n-octanol were used to synthesize the main agent SCA-2.Hexamethylenetetramine and vinyl carbonate were selected to prepare the curing agent YGA-1,which was then compounded with SCA-2 to develop a sand fixation and water plugging system.Firstly,single-factor experiments were conducted to determine the optimal concentrations of SCA-2 and YGA-1,subsequently,the system’s sand fixation and water blocking performance were evaluated.Finally,a pilot test was carried out in the mining site.Experimental results showed that the optimal formula composition of the system was 10%SCA-2+5%YGA-1.The gelation time of the system was 180 minutes and the viscosity after gelation could reach 108.4 mPa·s.When the dosage of the drug system was 0.6 PV,the sand production rate remained below 0.08%.Dual-tube parallel experiments showed that the sand fixation and water plugging system had a water flow channel plugging rate of 87.5%,while the oil flow channel plugging rate was only 11.3%,indicating minimal damage to the oil-bearing reservoir.The field test showed that after the measures taken in Well M of X oilfield,the sand free oil recovery period exceeded 360 days,the water content decreased by 5.0%and the cumulative oil production increased by 7092 m^(3).This study provides new ideas for efficient development of loose sandstone reservoirs. 展开更多
关键词 solidify sand and block water loose sandstone formula optimization performance evaluation field test
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Optimal Fuzzy Tracking Synthesis for Nonlinear Discrete-Time Descriptor Systems with T-S Fuzzy Modeling Approach
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作者 Yi-Chen Lee Yann-Horng Lin +2 位作者 Wen-Jer Chang Muhammad Shamrooz Aslam Zi-Yao Lin 《Computer Modeling in Engineering & Sciences》 2025年第5期1433-1461,共29页
An optimal fuzzy tracking synthesis for nonlinear discrete-time descriptor systems is discussed through the Parallel Distributed Compensation(PDC)approach and the Proportional-Difference(P-D)feedback framework.Based o... An optimal fuzzy tracking synthesis for nonlinear discrete-time descriptor systems is discussed through the Parallel Distributed Compensation(PDC)approach and the Proportional-Difference(P-D)feedback framework.Based on the Takagi-Sugeno Fuzzy Descriptor Model(T-SFDM),a nonlinear discrete-time descriptor system is represented as several linear fuzzy subsystems,which facilitates the linear P-D feedback technique and streamlines the fuzzy controller design process.Leveraging the P-D feedback fuzzy controller,the closed-loop T-SFDM can be transformed into a standard system that guarantees non-impulsiveness and causality for the nonlinear discrete-time descriptor system.In view of the disturbance problems,a passive performance constraint is incorporated into the fuzzy tracking synthesis to achieve dissipativity of disturbance energy.To achieve a better balance between state and control responses,the H2 performance requirement is considered and a minimization constraint is applied to optimize the H2 index.It is observed that there is a lack of research focusing on both disturbance and control input issues in nonlinear descriptor systems.Extending the Lyapunov theory,a stability analysis method is proposed for the tracking purpose with the combination of the free-weighting matrix to relax the analysis process while complying multiple performance constraints.Finally,two simulation examples are presented to demonstrate the feasibility and applicability of the proposed approach in practical control scenarios for nonlinear descriptor systems. 展开更多
关键词 Nonlinear descriptor system takagi-sugeno fuzzy model H2 performance passive performance robust-ness fuzzy tracking syhthesis
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Study the effect of using a dual rotor system on the performance of horizontal axis wind turbines using CFD
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作者 Amr Mokhtar Mahmoud Fouad +1 位作者 Mohamed Rashed Mostafa Mokhtar 《Global Energy Interconnection》 2025年第3期497-509,共13页
This research aims to improve the power output of a horizontal axis wind turbine(HAWT)by using an auxiliary rotor in front of the main rotor,this configuration is called a dual-rotor wind turbine(DRWT).The three-blade... This research aims to improve the power output of a horizontal axis wind turbine(HAWT)by using an auxiliary rotor in front of the main rotor,this configuration is called a dual-rotor wind turbine(DRWT).The three-bladed main rotor has a diameter of 0.9 m and both rotors with NREL S826 airfoil.ANSYS Fluent CFD simulation was used to optimize the DRWT performance where the numerical model was solved using the Realizable k-εt urbulence model.Four parameters are used,diameter ratio between the auxiliary front rotor and the main rear rotor(D_(R)=0.25,D_(R)=0.5,and D_(R)=0.75),axial free stream velocity according to the normal wind speed range in Egypt(V_(o)=5 m/s,V_o=7.5 m/s,and V_(o)=10 m/s),tip speed ratio which ranges from 2 to 8,and the number of blades of the front rotor(B=2,B=3 and B=4).The results show that increasing the number of blades positively impacts performance but at lower tip speed ratios.Smaller diameter ratios yield better performance,while increasing wind speed results in higher power.The best performance was achieved at freestream velocity V_(o)=10 m/s,diameter ratio D_(R)=0.25,front rotor number of blades B=4,and tip speed ratioλ=5 in which the overall maximum power coefficient Cp max=0.552 with an increase with 36.75%compared to the single rotor case. 展开更多
关键词 DUAL-ROTOR Power Freestream PERFORMANCE TURBINE AUXILIARY Diameter ratio
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Does ischemic preconditioning enhance sports performance more than placebo or no intervention?A systematic review with meta-analysis
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作者 Hiago L.R.Souza Géssyca T.Oliveira +5 位作者 Anderson Meireles Marcelo P.dos Santos Joao G.Vieira Rhai A.Arriel Stephen D.Patterson Moacir Marocolo 《Journal of Sport and Health Science》 2025年第2期21-34,共14页
Background:Ischemic preconditioning(IPC)is purported to have beneficial effects on athletic performance,although findings are inconsistent,with some studies reporting placebo effects.The majority of studies have inves... Background:Ischemic preconditioning(IPC)is purported to have beneficial effects on athletic performance,although findings are inconsistent,with some studies reporting placebo effects.The majority of studies have investigated IPC alongside a placebo condition,but without a control condition that was devoid of experimental manipulation,thereby limiting accurate determination of the IPC effects.Therefore,the aims of this study were to assess the impact of the IPC intervention,compared to both placebo and no intervention,on exercise capacity and athletic performance.Methods:A systematic search of PubMed,Embase,SPORTDiscus,Cochrane Library,and Latin American and Caribbean Health Sciences Literature(LILACS)covering records from their inception until July 2023 was conducted.To qualify for inclusion,studies had to apply IPC as an acute intervention,comparing it with placebo and/or control conditions.Outcomes of interest were performance(force,number of repetitions,power,time to exhaustion,and time trial performance),physiological measurements(maximum oxygen consumption,and heart rate),or perceptual measurements(RPE).For each outcome measure,we conducted 3 independent meta-analyses(IPC vs.placebo,IPC vs.control,placebo vs.control)using an inverse-variance random-effects model.The between-treatment effects were quantified by the standardized mean difference(SMD),accompanied by their respective 95%confidence intervals.Additionally,we employed the Grading of Recommendations,Assessment,Development and Evaluation(GRADE)approach to assess the level of certainty in the evidence.Results:Seventy-nine studies were included in the quantitative analysis.Overall,IPC demonstrates a comparable effect to the placebo condition(using a low-pressure tourniquet),irrespective of the subjects'training level(all outcomes presenting p>0.05),except for the outcome of time to exhaustion,which exhibits a small magnitude effect(SMD=0.37;p=0.002).Additionally,the placebo exhibited effects notably greater than the control condition(outcome:number of repetitions;SMD=0.45;p=0.03),suggesting a potential influence of participants'cognitive perception on the outcomes.However,the evidence is of moderate to low certainty,regardless of the comparison or outcome.Conclusion:IPC has significant effects compared to the control intervention,but it did not surpass the placebo condition.Its administration might be influenced by the cognitive perception of the receiving subject,and the efficacy of IPC as an ergogenic strategy for enhancing exercise capacity and athletic performance remains questionable. 展开更多
关键词 DECEPTION Nocebo effects Athletic performance REPERFUSION TOURNIQUETS
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Do compression garments enhance running performance?An updated systematic review and meta-analysis
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作者 Wei Wang Yana Wang +7 位作者 Yufeng Zhang Dongyang Si Xingyang Li Qingsong Liang Qianteng Li Lingyan Huang Shutao Wei Yu Liu 《Journal of Sport and Health Science》 2025年第3期109-119,共11页
Background:Despite the wide use of compression garments to enhance athletic running performance,evidence supporting improvements has not been conclusive.This updated systematic review and meta-analysis of randomized c... Background:Despite the wide use of compression garments to enhance athletic running performance,evidence supporting improvements has not been conclusive.This updated systematic review and meta-analysis of randomized controlled trials(RCTs)compared the effects of compression garment wearing with those of non-compression garment wearing(controls)during running on improving running performance.Methods:A comprehensive search was conducted in the electronic databases(Web of Science,EBSCOhost,PubMed,Embase,Scopus,and Cochrane)for RCTs comparing running performance between runners wearing compression garments and controls during running,from inception to September 2024.Independent reviewers screened studies,extracted data,appraised risk of bias(RoB 2)and certainty of evidence(Grading of Recommendations Assessments,Development and Evaluation(GRADE)).Primary outcomes were race time and time to exhaustion.Secondary outcomes covered running speed and race pace,submaximal oxygen uptake,tissue oxygenation,and soft tissue vibration.Randomeffects meta-analyses were conducted to generate pooled estimates,expressed in standardized mean difference(SMD).Subgroup differences of garment,race type,and contact surface were tested in moderator analyses.Results:The search yielded 51 eligible studies comprising 899 participants,of which 33 studies were available for meta-analysis of primary outcomes.Runners wearing compression garments during running showed no significant improvement in race time(SMD=-0.07,95%CI:-0.22 to 0.09;p=0.40)or time to exhaustion(SMD=0.04,95%CI:-0.20 to 0.29;p=0.72).Moderator analyses indicated no effects from garment type,race type,or surface.Secondary outcomes also showed no performance benefits,although compression garments significantly reduced soft tissue vibration(SMD=-0.43,95%CI:-0.70 to-0.15;p<0.01).Certainty of evidence was rated low to very low.Conclusion:Data synthesis of current RCTs offers no updated evidence favoring the support of wearing compression garments during running as a viable strategy for improving running and endurance performance among runners of varying performance levels and types of running races. 展开更多
关键词 RUNNERS Performance enhancement SPRINT ENDURANCE
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Investigation on the Influence of Mooring System Configuration on the Hydrodynamic Performance of an Oscillating Water Column Array System
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作者 XU Sheng JU Kun +2 位作者 JI Chun-yan DAI Sai-shuai YUAN Zhi-ming 《China Ocean Engineering》 2025年第6期1054-1069,共16页
This paper presents a multi-module oscillating water column(OWC)wave energy converter(WEC)array system,comprising seven interconnected OWC modules.The modules are connected by elastic ropes with clumped weights positi... This paper presents a multi-module oscillating water column(OWC)wave energy converter(WEC)array system,comprising seven interconnected OWC modules.The modules are connected by elastic ropes with clumped weights positioned at the ropes'midpoints.Three distinct mooring systems are designed for this OWC array,and the impact of mooring configurations on the hydrodynamic responses of the OWCs and mooring tensions is thoroughly examined.Three-dimensional potential flow theory is applied to perform time domain analyses.The motion responses of representative modules,the tension of specific mooring lines,and the spacing between adjacent modules in the array system are investigated through a comprehensive coupled dynamic analysis in the time domain.Based on these analyses,recommendations are provided for the optimal mooring system configuration for the array system. 展开更多
关键词 OWC array system mooring system hydrodynamic performance
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In-band full-duplex MIMO PLC systems for relaying networks
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作者 Francisco J.Canete Gautham Prasad Lutz Lampe 《Digital Communications and Networks》 2025年第1期145-159,共15页
In Power Line Communications(PLC),there are regulatory masks that restrict the transmit power spectral density for electromagnetic compatibility reasons,which creates coverage issues despite the not too long distances... In Power Line Communications(PLC),there are regulatory masks that restrict the transmit power spectral density for electromagnetic compatibility reasons,which creates coverage issues despite the not too long distances.Hence,PLC networks often employ repeaters/relays,especially in smart grid neighborhood area networks.Even in broadband indoor PLC systems that offer a notable data rate,relaying may pave the way to new applications like being the backbone for wireless technologies in a cost-effective manner to support the Internet-of-things paradigm.In this paper,we study Multiple-Input Multiple-Output(MIMO)PLC systems that incorporate inband full-duplex functionality in relaying networks.We present several MIMO configurations that allow end-to-end half-duplex or full-duplex operations and analyze the achievable performance with state-of-the-art PLC systems.To reach this analysis,we get channel realizations from random network layouts for indoor and outdoor scenarios.We adopt realistic MIMO channel and noise models and consider transmission techniques according to PLC standards.The concepts discussed in this work can be useful in the design of future PLC relay-aided networks for different applications that look for a coverage extension and/or throughput:smart grids with enhanced communications in outdoor scenarios,and“last meter”systems for high-speed connections everywhere in indoor ones. 展开更多
关键词 PLC MIMO Relaying networks OFDM Spatial correlation Performance analysis
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Improving the Performance of Thermoelectric Systems for Air Conditioning Using Different Configurations
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作者 Hind Abdulrahman Mahmood Ameer Abed Jaddoa Mohammed K.Al-Saadi 《Frontiers in Heat and Mass Transfer》 2025年第4期1281-1302,共22页
Thermoelectric air conditioning systems based on the Peltier effect had two modes:heating and cooling.In this work,the proposed design provides continuous improvement in COP from the first minute of operation.In cooli... Thermoelectric air conditioning systems based on the Peltier effect had two modes:heating and cooling.In this work,the proposed design provides continuous improvement in COP from the first minute of operation.In cooling mode,the coefficient of performance(COP)was 1.176 due to the techniques used in this device,and it increased to 1.24 in the last minute of operation.Concerning the steady-state scenario,from the first minute,the Qc was larger than the W for the entire duration of the operation.The output temperature reaches 18.97℃ ,and the temperature on the cold side reaches 4.96℃ in the fifteen minutes of operation.The cooling mood was checked in Iraq/Baghdad in October with a temperature of 31℃ .Furthermore,the heating mode was checked in December with a temperature of 22℃ .Due to the size of the component on the cold side being small compared with the size of the component on the heat side,it reached a steady state in 13 min.This means the COP in heating mode reached 1.01 in 14 min.Furthermore,due to the presence of a thermal insulator made inside the device to separate the cold side and the hot side,the difference in temperature causes a noticeable little ascent.This is why the COP increased because it kept the degree differences low.Performance enhancements were achieved by optimizing the behavior of thermoelectric materials.The device contains 3 Peltier elements,a water-cooled system with one Peltier,a heat sink,and a fan.The design of the dehumidification system addresses the humidity issue commonly associated with thermoelectric air conditioners.In this context,the results indicate that the humidity rates had decreased and the cooling rate had increased with these innovative techniques,and thus,excellent performance can be achieved even if the Seebeck coefficient is not at its highest based on the condition of providing the Peltier elements’reliability and optimal thermal performance for various applications requiring both cooling and heating functions.The insulation plays a critical role in maintaining the efficiency of the system,reducing energy consumption,and ensuring long-term functionality.The proposed system is valuable for devices or environments that demand precise and dual thermal control with minimal energy wastage. 展开更多
关键词 Peltier effect Seebeck coefficient COP THERMOELECTRIC air conditioning performance enhancement
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A Systematic Review of YOLO-Based Object Detection in Medical Imaging:Advances,Challenges,and Future Directions
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作者 Zhenhui Cai Kaiqing Zhou Zhouhua Liao 《Computers, Materials & Continua》 2025年第11期2255-2303,共49页
The YOLO(You Only Look Once)series,a leading single-stage object detection framework,has gained significant prominence in medical-image analysis due to its real-time efficiency and robust performance.Recent iterations... The YOLO(You Only Look Once)series,a leading single-stage object detection framework,has gained significant prominence in medical-image analysis due to its real-time efficiency and robust performance.Recent iterations of YOLO have further enhanced its accuracy and reliability in critical clinical tasks such as tumor detection,lesion segmentation,and microscopic image analysis,thereby accelerating the development of clinical decision support systems.This paper systematically reviews advances in YOLO-based medical object detection from 2018 to 2024.It compares YOLO’s performance with othermodels(e.g.,Faster R-CNN,RetinaNet)inmedical contexts,summarizes standard evaluation metrics(e.g.,mean Average Precision(mAP),sensitivity),and analyzes hardware deployment strategies using public datasets such as LUNA16,BraTS,andCheXpert.Thereviewhighlights the impressive performance of YOLO models,particularly from YOLOv5 to YOLOv8,in achieving high precision(up to 99.17%),sensitivity(up to 97.5%),and mAP exceeding 95%in tasks such as lung nodule,breast cancer,and polyp detection.These results demonstrate the significant potential of YOLO models for early disease detection and real-time clinical applications,indicating their ability to enhance clinical workflows.However,the study also identifies key challenges,including high small-object miss rates,limited generalization in low-contrast images,scarcity of annotated data,and model interpretability issues.Finally,the potential future research directions are also proposed to address these challenges and further advance the application of YOLO models in healthcare. 展开更多
关键词 YOLO medical imaging object detection performance analysis core challenges
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Modeling and Performance Evaluation of Streaming Data Processing System in IoT Architecture
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作者 Feng Zhu Kailin Wu Jie Ding 《Computers, Materials & Continua》 2025年第5期2573-2598,共26页
With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Alth... With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Although distributed streaming data processing frameworks such asApache Flink andApache Spark Streaming provide solutions,meeting stringent response time requirements while ensuring high throughput and resource utilization remains an urgent problem.To address this,the study proposes a formal modeling approach based on Performance Evaluation Process Algebra(PEPA),which abstracts the core components and interactions of cloud-based distributed streaming data processing systems.Additionally,a generic service flow generation algorithmis introduced,enabling the automatic extraction of service flows fromthe PEPAmodel and the computation of key performance metrics,including response time,throughput,and resource utilization.The novelty of this work lies in the integration of PEPA-based formal modeling with the service flow generation algorithm,bridging the gap between formal modeling and practical performance evaluation for IoT systems.Simulation experiments demonstrate that optimizing the execution efficiency of components can significantly improve system performance.For instance,increasing the task execution rate from 10 to 100 improves system performance by 9.53%,while further increasing it to 200 results in a 21.58%improvement.However,diminishing returns are observed when the execution rate reaches 500,with only a 0.42%gain.Similarly,increasing the number of TaskManagers from 10 to 20 improves response time by 18.49%,but the improvement slows to 6.06% when increasing from 20 to 50,highlighting the importance of co-optimizing component efficiency and resource management to achieve substantial performance gains.This study provides a systematic framework for analyzing and optimizing the performance of IoT systems for large-scale real-time streaming data processing.The proposed approach not only identifies performance bottlenecks but also offers insights into improving system efficiency under different configurations and workloads. 展开更多
关键词 system modeling performance evaluation streaming data process IoT system PEPA
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Ethical implications of artificial intelligence in sport:A systematic scoping review
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作者 Jae-Hak Kim Janghyeon Kim +1 位作者 Hoseok Kang Bo-Young Youn 《Journal of Sport and Health Science》 2025年第4期11-21,共11页
Background:Although there is growing evidence of the use of artificial intelligence(AI)techniques in sports,ethical issues surrounding AI use are being discussed at a minimal level.Thus,this systematic scoping review ... Background:Although there is growing evidence of the use of artificial intelligence(AI)techniques in sports,ethical issues surrounding AI use are being discussed at a minimal level.Thus,this systematic scoping review aimed to summarize the current ethical implications associated with using AI in sports.Methods:In this study,a total of 9 databases-MEDLINE/PubMed,Embase,Cochrane Library,ProQuest,EBSCOhost,IEEE Xplore,Web of Science,Scopus,and Google Scholar--were searched.The review protocol was registered(https://osfio/42a8q)before extracting data.The search yielded 397 studies,and 25 studies met the inclusion and exclusion criteria.Results:The 25 studies were categorized into 4 primary ethical concerns:fairness and bias,transparency and explainability,privacy and data ethics,and accountability in AI's application in sports.These categorizations were derived based on the systematic review ofethical issues highlighted across the selected studies.Fifteen studies delved into fairness and bias,focusing on how AI can perpetuate existing inequalities in sports.Thirteen studies addressed the lack of transparency,emphasizing the challenges in interpretability and trust in AI-driven decisions.Privacy and data ethics emerged as significant in22 studies,highlighting risks related to the misuse of athletes’sensitive data.Finally,account-ability was examined in 8 studies,stressing the ethical obligations of AI developers and users in sports contexts.The thematic analysis revealed overlapping concerns,as some studies addressed multiple issues simultaneously.Conclusion:Future research should focus on developing ethical frameworks tailored to underrepresented sports contexts and creating global standards for AI regulation in sports.This includes investigating the implications of AI applications in amateur sports,enhancing diversity in AI training datasets,and exploring the integration of ethical AI practices across various sports governance structures. 展开更多
关键词 ATHLETES Sports performance Sports technology Sports dat Sports governance
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Strategic Role of Green Accounting in the Digital Era:A Systematic Review of Its Impact on ESG Disclosure and Investment Decisions
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作者 Reyinhard Sinaga Willman Sihotang +1 位作者 Iskandar Muda Erlina 《Journal of Modern Accounting and Auditing》 2025年第3期183-196,共14页
Accounting's emphasis has changed from standard financial reporting to sustainability reporting that takes environmental factors into account as a result of the sustainable development paradigm's evolution.In ... Accounting's emphasis has changed from standard financial reporting to sustainability reporting that takes environmental factors into account as a result of the sustainable development paradigm's evolution.In order to facilitate the incorporation of environmental data into the ESG(Environmental,Social,and Governance)reporting framework,green accounting has become a popular strategic approach.A comprehensive evaluation of recent research on the effects of green accounting on the quality of ESG disclosure,risk perception,and investment decision-making,as well as the use of digital technology in corporate operations,is the goal of this study.By analyzing 74 Scopus-indexed articles published between 2021 and 2024,this study finds that the integration of green accounting enhances the transparency and accountability of environmental reporting,influences firm valuation,and serves as a credibility signal to the market.Furthermore,the adoption of technologies such as AI,blockchain,and big data has proven to improve the accuracy and effectiveness of green accounting practices,although technical and resource-related challenges remain,particularly in developing countries and the SME sector.This study makes both theoretical and practical contributions to support more sustainable decision-making and proposes a future research agenda that position green accounting as a strategic instrument within the green economy. 展开更多
关键词 green accounting environmental accounting sustainability accounting ESG performance
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