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The Additive Manufacturing Process of Electric Power Fittings Fabricated by Metal Droplet Deposition
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作者 Haihua Wu Guangxi Zhao Zhengying Wei 《Mechanical Engineering Science》 2019年第1期26-31,共6页
Metal droplet deposition is a kind of additive manufacturing(3D Printing)technique that fabricates near-net part through droplets deposition with lower cost and higher efficiency.This paper proposed a solution to prob... Metal droplet deposition is a kind of additive manufacturing(3D Printing)technique that fabricates near-net part through droplets deposition with lower cost and higher efficiency.This paper proposed a solution to problems of electric power fittings that large inventories,high procurement costs,low manufacturing efficiency and transportation cost.Using additive Manufacturing technique-metal droplet deposition,electric power fittings fabricated on power construction site.This paper describes the manufacturing process of typical thin-walled samples(the structure optimized based on additive manufacturing principle)and ball head rings of electric power fittings.Aiming at the integral AM forming for ball and ball socket electric power fitting workpiece,a novel easy removal forming support material(ceramics and gypsum mixed with UV cured resin)have been developed.Here this support material was used to fabricate nested integral workpieces.Dimensional accuracy and microstructure of the test pieces were analyzed.The error of the height and width of the forming workpiece is within 5%.No obvious overlap trace(such as overlap line and cracks)observed,and the internal microstructure is equiaxial crystal.The average density of the component is 99.51%,which measured by drainage method and 13.39%higher than the cast raw material. 展开更多
关键词 ADDITIVE manufacturing METAL droplets Electric power fittings THIN-WALLED sample BALL head RINGS workpiece.
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Effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness:A multi-country cluster randomized controlled trial
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作者 Tania Pinto-Escalona Erica Gobbi +5 位作者 Pedro L.Valenzuela Simon J.Bennett Pierluigi Aschieri Manuel Martin-Loeches Antonio Paoli Oscar Martinez-de-Quel 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期90-98,共9页
Purpose:To examine the effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness in children aged 7-8 years.Methods:Twenty schools in 5 different European coun... Purpose:To examine the effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness in children aged 7-8 years.Methods:Twenty schools in 5 different European countries(2 second-grade classrooms per school)participated in a cluster randomized controlled trial(Sport at School trial).Participants were assigned to either a control group,which continued with their habitual physical education lessons,or to an intervention group,which replaced these lessons with a 1-year karate intervention(Karate Mind and Movement program).A total of 721 children(344 girls and 377 boys,7.4±0.5 years old,mean±SD)completed the study,of which 333 and 388 were assigned to the control group and intervention group,respectively.Outcomes included academic performance(average grade),psychosocial functioning(Strengths and Difficulties Questionnaire for parents),and different markers of physical fitness(cardiorespiratory fitness,balance,and flexibility).Results:The intervention provided small but significant benefits compared to the control group for academic achievement(d=0.16;p=0.003),conduct problems(d=-0.28;p=0.003),cardiorespiratory fitness(d=0.36;p<0.001),and balance(d=0.24;p=0.015).There was a trend towards significant benefits for flexibility(d=0.24;p=0.056).No significant benefits were observed for other variables,including psychosocial difficulties,emotional symptoms,hyperactivity/inattention,peer problems,or prosocial behaviour(all p>0.05).Conclusion:A 1-year school-based karate intervention was effective in improving academic achievement,conduct problems,and physical fitness in primary school children.The results support the inclusion of karate during physical education lessons. 展开更多
关键词 Academic performance Cardiorespiratory fitness Conduct problems KARATE Physical fitness
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Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly
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作者 Tim Böttrich Pascal Bauer +11 位作者 Vincent Gröober Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski Franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten Krüger Christopher Weyh 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期288-296,I0002,共10页
Background:Atherosclerosis forms the pathological basis for the development of cardiovascular disease.Since pathological processes initially develop without clinically relevant symptoms,the identification of early mar... Background:Atherosclerosis forms the pathological basis for the development of cardiovascular disease.Since pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early interventions.There is evidence that regulatory T cells(Tregs)are involved in the development of atherosclerosis.Therefore,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated signatures.Methods:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking medication.Ultrasound of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were performed.Additionally,tests were conducted to assess blood lipids and determine glucose levels.Immunophenotyping of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow cytometry.Participants were categorized according to atherosclerotic plaque status.Linear and logistic regression models were used to analyze associations between parameters.Results:SAP was detected in a total of 29 participants.The participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and mTregs(OR=1.05(95%CI:1.021.10))as independent risk factors for SAP.Stepwise linear regression could reveal an association of peak oxygen uptake(b=0.441),low-density lipoprotein(LDL)(b=0.096),and SAP(b=6.733)with mTregs and LDL(b=0.104)with rTregs.Conclusion:While at an early stage of SAP,the total proportion of Tregs gives no indication of vascular changes,this is indicated by a shift in the Treg subgroups.Factors such as serum LDL or cardiopulmonary fitness may be associated with this shift and may also be additional diagnostic indicators.This could be used to initiate lifestyle-based preventive measures at an early stage,which may have a protective effect against disease progression. 展开更多
关键词 Cardiorespiratory fitness ELDERLY Regulatory T cells Subclinical atherosclerosis
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e^(+)e^(-)→Λ_(c)+Λ_(c)^(- ) Cross Sections and the Λ_(c)^(+) Electromagnetic Form Factors within the Extended Vector Meson Dominance Model
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作者 陈诚 闫冰 谢聚军 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期36-41,共6页
Within the extended vector meson dominance model,we investigate the𝑒e^(+)e^(-)→Λ_(c)+Λ_(c)^(- ) reaction and the electromagnetic form factors of the charmed baryon𝛬 Λ_(c)^(+)𝑐.The model par... Within the extended vector meson dominance model,we investigate the𝑒e^(+)e^(-)→Λ_(c)+Λ_(c)^(- ) reaction and the electromagnetic form factors of the charmed baryon𝛬 Λ_(c)^(+)𝑐.The model parameters are determined by fitting them to the cross sections of the process𝑒e^(+)e^(-)→Λ_(c)+Λ_(c)^(- ) and the magnetic form factor|G_(M)|of Λ_(c)^(+) .By considering four charmonium-like states,called𝜓(4500),𝜓(4660),𝜓(4790),and𝜓(4900),we can well describe the current data on the𝑒e^(+)e^(-)→Λ_(c)+Λ_(c)^(- ) reaction from the reaction threshold up to 4.96 GeV.In addition to the total cross sections and|𝐺M|,the ratio|G_(E)/G_(M)|and the effective form factor|Geff|for Λ_(c)^(+) 𝑐are also calculated,and found that these calculations are consistent with the experimental data.Within the fitted model parameters,we have also estimated the charge radius of the charmed Λ_(c)^(+) baryon. 展开更多
关键词 fitted RADIUS MESON
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A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes
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作者 LuHuai Jiao Xin Ma +3 位作者 YuanNong Zhang TaiFeng Jin Song Fu BinBin Ni 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期368-374,共7页
The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation belts.Increased measurements have indicated that the commonly used Maxwellian and Kappa di... The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation belts.Increased measurements have indicated that the commonly used Maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt electrons.Here we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen Probes.By calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic conditions.In this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the Maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions. 展开更多
关键词 radiation belt electron Kappa-type distribution fitting geomagnetic storm
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Microscopic defects formation and dynamic mechanical response analysis of Q345 steel plate subjected to explosive load
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作者 Zhengqing Zhou Zechen Du +6 位作者 Yulong Zhang Guili Yang Ruixiang Wang Yuzhe Liu Peize Zhang Yaxin Zhang Xiao Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期430-442,共13页
As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate unde... As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate under the explosive load and its macroscopic dynamics simulation. Firstly, the defect characteristics of the steel plate were investigated by stereoscopic microscope(SM) and scanning electron microscope(SEM). At the macroscopic level, the defect was the formation of cave which was concentrated in the range of 0-3.0 cm from the explosion center, while at the microscopic level, the cavity and void formation were the typical damage characteristics. It also explains that the difference in defect morphology at different positions was the combining results of high temperature and high pressure. Secondly, the variation rules of mechanical properties of steel plate under explosive load were studied. The Arbitrary Lagrange-Euler(ALE) algorithm and multi-material fluid-structure coupling method were used to simulate the explosion process of steel plate. The accuracy of the method was verified by comparing the deformation of the simulation results with the experimental results, the pressure and stress at different positions on the surface of the steel plate were obtained. The simulation results indicated that the critical pressure causing the plate defects may be approximately 2.01 GPa. On this basis, it was found that the variation rules of surface pressure and microscopic defect area of the Q345 steel plate were strikingly similar, and the corresponding mathematical relationship between them was established. Compared with Monomolecular growth fitting models(MGFM) and Logistic fitting models(LFM), the relationship can be better expressed by cubic polynomial fitting model(CPFM). This paper illustrated that the explosive defect characteristics of metal plate at the microscopic level can be explored by analyzing its macroscopic dynamic mechanical response. 展开更多
关键词 Explosive load Q345 steel Micro defect Finite element simulation Dynamic response Data fitting
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Determination of Material Parameters of EVA Foam under Uniaxial Compressive Testing Using Hyperelastic Models
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作者 Nattapong Sangkapong Fasai Wiwatwongwana Nattawit Promma 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期800-804,共5页
The objective of this research was to determine the mechanical parameter from EVA foam and also investigate its behavior by using Blatz-Ko,Neo-Hookean,Mooney model and experimental test.The physical characteristic of ... The objective of this research was to determine the mechanical parameter from EVA foam and also investigate its behavior by using Blatz-Ko,Neo-Hookean,Mooney model and experimental test.The physical characteristic of EVA foam was also evaluated by scanning electron microscopy(SEM).The results show that Blatz-Ko and Neo-Hookean model can fit the curve at 5%and 8%strain,respectively.The Mooney model can fit the curve at 50%strain.The modulus of rigidity evaluated from Mooney model is 0.0814±0.0027 MPa.The structure of EVA foam from SEM image shows that EVA structure is a closed cell with homogeneous porous structure.From the result,it is found that Mooney model can adjust the data better than other models.This model can be applied for mechanical response prediction of EVA foam and also for reference value in engineering application. 展开更多
关键词 hyperelastic models modulus of rigidity EVA foam curve fitting method strain energy function uniaxial compressive testing
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The Impact and Intervention of Handheld Tai Chi Water-Resistance Fitness Ball on Middle-Aged and Elderly Patients with Parkinson’s Disease
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作者 He Huang 《Health》 2024年第4期319-349,共31页
Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionna... Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionnaire on exercise compliance for patients with Parkinson’s disease was developed, and its reliability and validity were tested. Then, a survey was conducted to investigate the current status of exercise compliance among Parkinson’s disease patients, including general information, scoring status, and single and multiple factor analyses of influencing factors [1]. The results of the study show that through qualitative research, the dimensions and item pools of the questionnaire were initially constructed, and the reliability analysis of the questionnaire was conducted through Delphi expert consultation, with favorable results in terms of its reliability and validity [2]. Regarding the current status of exercise compliance among Parkinson’s disease patients, the study found that the level of exercise compliance needs improvement, and there are significant differences in exercise compliance levels among patients under different circumstances. Finally, the research results were discussed and conclusions were drawn. The innovation of this study lies in the development of a questionnaire on exercise compliance for patients with Parkinson’s disease and the preliminary qualitative research and Delphi expert consultation conducted on it, providing new ideas and methods for the study of exercise compliance. However, the study also has limitations as it did not examine the effects of other interventions on Parkinson’s disease, so further research should be conducted [3]. 展开更多
关键词 Parkinson’s Disease Exercise Compliance Tai Chi Water Resistance Fitness Ball Influencing Factors Intervention Effectiveness
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Method for Improving Digital Elevation Model Precision of Consumer Level Unmanned Aerial Vehicles
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作者 Qiuxin XIA Zhong LI +2 位作者 Yong ZHOU Ensi ZHANG Gang YANG 《Meteorological and Environmental Research》 2024年第2期71-77,共7页
Currently,the aerial survey system of low-altitude unmanned aerial vehicles(UAVs)has been widely used in acquiring digital map 4D products,mapping,digital linear maps,and other aspects.However,there are problems,such ... Currently,the aerial survey system of low-altitude unmanned aerial vehicles(UAVs)has been widely used in acquiring digital map 4D products,mapping,digital linear maps,and other aspects.However,there are problems,such as low precision and weak practicability in constructing digital elevation model(DEM)products through the data collected using consumption level UAVs.Therefore,improving the accuracy of DEM products obtained by consumption level UAVs is a crucial and complex issue in the research of UAV aerial survey systems.In precision elevation measurement,the geodetic height of a certain number of ground points with reasonable distribution in the region is often obtained first.Then,the normal height of the ground points is obtained by leveling,and the elevation residual value surface of the region is fitted.Finally,the normal height of the points to be solved in the region is obtained by fitting the elevation residual surface.Therefore,the elevation residual fitting method was used to improve the accuracy of consumer UAV DEM products in this study.First,a high-quality ground point cloud was obtained by constructing the gradient filtering-cloth simulation filtering(GF-CSF)model.Second,an abnormal elevation fitting residual DEM model was constructed.Lastly,the final DEM was obtained using the DEM difference method.The experimental results show that among the 20 random sampling inspection points,the average elevation residual was 2.3 mm,and the root mean square error(RMSE)was 16.7 mm after the DEM accuracy was improved by the method.The average elevation residual without improving the DEM accuracy was 28.6 mm,and RMSE was 33.7 mm. 展开更多
关键词 UAV aerial survey GF CSF DEM Surface fitting
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Exploring a New Lifetime Distribution for Modelling the Waiting Time of Bank Customers
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作者 Simon A. Ogumeyo Jacob C. Ehiwario Festus C. Opone 《Journal of Applied Mathematics and Physics》 2024年第1期194-209,共16页
The fitting of lifetime distribution in real-life data has been studied in various fields of research. With the theory of evolution still applicable, more complex data from real-world scenarios will continue to emerge... The fitting of lifetime distribution in real-life data has been studied in various fields of research. With the theory of evolution still applicable, more complex data from real-world scenarios will continue to emerge. Despite this, many researchers have made commendable efforts to develop new lifetime distributions that can fit this complex data. In this paper, we utilized the KM-transformation technique to increase the flexibility of the power Lindley distribution, resulting in the Kavya-Manoharan Power Lindley (KMPL) distribution. We study the mathematical treatments of the KMPL distribution in detail and adapt the widely used method of maximum likelihood to estimate the unknown parameters of the KMPL distribution. We carry out a Monte Carlo simulation study to investigate the performance of the Maximum Likelihood Estimates (MLEs) of the parameters of the KMPL distribution. To demonstrate the effectiveness of the KMPL distribution for data fitting, we use a real dataset comprising the waiting time of 100 bank customers. We compare the KMPL distribution with other models that are extensions of the power Lindley distribution. Based on some statistical model selection criteria, the summary results of the analysis were in favor of the KMPL distribution. We further investigate the density fit and probability-probability (p-p) plots to validate the superiority of the KMPL distribution over the competing distributions for fitting the waiting time dataset. 展开更多
关键词 KM-Transformation Power Lindley Distribution Data Fitting MOMENTS QUANTILES
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Market Positioning Analysis of CJ Brand Fitness Equipment
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作者 Bohan Liu Yuying Li +2 位作者 Ping Yu Jiayue Zhou Kang Fang 《Proceedings of Business and Economic Studies》 2024年第2期89-94,共6页
CJ Health Technology Co.has been an export-oriented supplier of fitness equipment,boasting leading technology innovation and manufacturing capabilities.However,in the process of expanding into the domestic market,the ... CJ Health Technology Co.has been an export-oriented supplier of fitness equipment,boasting leading technology innovation and manufacturing capabilities.However,in the process of expanding into the domestic market,the challenges of unclear market positioning and lack of brand awareness have emerged as major obstacles.To address these issues,a SWOT analysis was conducted to explore a suitable market positioning strategy for the CJ brand.The analysis reveals that the market demand for commercial fitness equipment is relatively saturated,with fierce competition.In contrast,the home fitness market represents a new blue ocean with promising development opportunities for the CJ brand.Leveraging excellent product quality,stringent quality control measures,and innovation-driven cutting-edge technology,it is recommended that CJ brand fitness equipment target young customers aged between 25 and 35 years old.Additionally,vigorously developing the home fitness product line is proposed to capitalize on this burgeoning market segment. 展开更多
关键词 Fitness equipment Brand planning Market positioning SWOT
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Research on the Deep Integration Mechanism of National Fitness Campaign and College Physical Education Teaching:Taking Guangdong University of Science and Technology as an Example
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作者 Junmei Cui Yanqing Yan 《Journal of Contemporary Educational Research》 2024年第1期107-115,共9页
By using the methods of literature review,questionnaire survey,and expert interview,this paper discusses and analyzes the deep integration mechanism of national fitness campaign and college physical education teaching... By using the methods of literature review,questionnaire survey,and expert interview,this paper discusses and analyzes the deep integration mechanism of national fitness campaign and college physical education teaching,in order to promote the development of college physical education teaching reform,expand ideas,explore new fields,and provide novel development directions.The purpose is to enhance the national physical quality,improve the public service system,enhance the health awareness of the citizens,and provide guidelines for promoting the development of sports. 展开更多
关键词 National fitness campaign College physical education Deep integration Mechanism
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海外
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《中国会展》 2024年第3期17-17,共1页
西班牙2024年第44届西班牙国际旅游展召开。本刊讯(编辑赵一霖)第44届西班牙国际旅游交易会(英文简写:FITUR 2024,中文名称也被译为西班牙国际旅游展或马德里国际旅游展)于1月24日—28日在马德里成功举办。在为期五天的展会期间,据官方... 西班牙2024年第44届西班牙国际旅游展召开。本刊讯(编辑赵一霖)第44届西班牙国际旅游交易会(英文简写:FITUR 2024,中文名称也被译为西班牙国际旅游展或马德里国际旅游展)于1月24日—28日在马德里成功举办。在为期五天的展会期间,据官方报告显示,FITUR 2024的参展企业数量创下历史新高。 展开更多
关键词 官方报告 英文简写 中文名称 马德里 历史新高 FIT 西班牙 参展企业
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Optimizing Grey Wolf Optimization: A Novel Agents’ Positions Updating Technique for Enhanced Efficiency and Performance
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作者 Mahmoud Khatab Mohamed El-Gamel +2 位作者 Ahmed I. Saleh Asmaa H. Rabie Atallah El-Shenawy 《Open Journal of Optimization》 2024年第1期21-30,共10页
Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of ... Grey Wolf Optimization (GWO) is a nature-inspired metaheuristic algorithm that has gained popularity for solving optimization problems. In GWO, the success of the algorithm heavily relies on the efficient updating of the agents’ positions relative to the leader wolves. In this paper, we provide a brief overview of the Grey Wolf Optimization technique and its significance in solving complex optimization problems. Building upon the foundation of GWO, we introduce a novel technique for updating agents’ positions, which aims to enhance the algorithm’s effectiveness and efficiency. To evaluate the performance of our proposed approach, we conduct comprehensive experiments and compare the results with the original Grey Wolf Optimization technique. Our comparative analysis demonstrates that the proposed technique achieves superior optimization outcomes. These findings underscore the potential of our approach in addressing optimization challenges effectively and efficiently, making it a valuable contribution to the field of optimization algorithms. 展开更多
关键词 Grey Wolf Optimization (GWO) Metaheuristic Algorithm Optimization Problems Agents’ Positions Leader Wolves Optimal Fitness Values Optimization Challenges
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清华大学等40所高校联合组织互联网创新 国家未来互联网试验设施FITI项目推进会举行
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作者 吴建平 《中国教育网络》 2023年第5期8-8,共1页
5月12日,未来网络试验设施国家重大科技基础设施:未来互联网试验设施FITI项目推进工作会议在清华大学举行。清华大学等40所项目承建高校负责人员100多人参会。FITI项目负责人,清华大学吴建平院士表示,FITI项目是面向未来互联网体系结构... 5月12日,未来网络试验设施国家重大科技基础设施:未来互联网试验设施FITI项目推进工作会议在清华大学举行。清华大学等40所项目承建高校负责人员100多人参会。FITI项目负责人,清华大学吴建平院士表示,FITI项目是面向未来互联网体系结构创新的国家重大科技基础设施,旨在为研究和设计各种创新未来网络体系结构提供国际领先的开放性试验环境,是继中国教育和科研计算机网CERNET和CERNET2之后,由清华大学等40所高校联合攻关的又一个重大互联网实验平台。 展开更多
关键词 未来互联网 未来网络体系结构 CERNET2 试验设施 吴建平 互联网创新 清华大学 FIT
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Scoping review on health-related physical fitness in patients with inflammatory bowel disease:Assessment,interventions,and future directions 被引量:1
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作者 Karlijn Demers Michiel T J Bak +4 位作者 Bart C Bongers Annemarie C de Vries Daisy M A E Jonkers Marieke J Pierik Laurents P S Stassen 《World Journal of Gastroenterology》 SCIE CAS 2023年第38期5406-5427,共22页
BACKGROUND Reaching the Selecting Therapeutic Targets in Inflammatory Bowel Disease-II(STRIDE-II)therapeutic targets for inflammatory bowel disease(IBD)requires an interdisciplinary approach.Lifestyle interventions fo... BACKGROUND Reaching the Selecting Therapeutic Targets in Inflammatory Bowel Disease-II(STRIDE-II)therapeutic targets for inflammatory bowel disease(IBD)requires an interdisciplinary approach.Lifestyle interventions focusing on enhancing and preserving health-related physical fitness(HRPF)may aid in improving subjective health,decreasing disability,or even controlling inflammation.However,ambiguity remains about the status and impact of HRPF(i.e.body composition,cardiorespiratory fitness,muscular strength,muscular endurance,and flexibility)in IBD patients,hindering the development of physical activity and physical exercise training guidelines.AIM To review HRPF components in IBD patients and the impact of physical activity and physical exercise training interventions on HRPF.METHODS A systematic search in multiple databases was conducted for original studies that included patients with IBD,assessed one or more HRPF components,and/or evaluated physical activity or physical exercise training interventions.RESULTS Sixty-eight articles were included.No study examined the complete concept of HRPF,and considerable heterogeneity existed in assessment methods,with frequent use of non-validated tests.According to studies that used gold standard tests,cardiorespiratory fitness seemed to be reduced,but findings on muscular strength and endurance were inconsistent.A limited number of studies that evaluated physical activity or physical exercise training interventions reported effects on HRPF,overall showing a positive impact.CONCLUSION We performed a scoping review using a systematic and iterative approach to identify and synthesize an emerging body of literature on health-related physical fitness in patients with IBD,highlighting several research gaps and opportunities for future research.Findings of this review revealed a gap in the literature regarding the accurate assessment of HRPF in patients with IBD and highlighted important methodological limitations of studies that evaluated physical activity or physical exercise training interventions.This scoping review is a step towards performing studies and systematic reviews in the future,which was not possible at present given the heterogeneity in endpoints and designs of the available studies on this topic.Future well-designed studies are required to determine the optimal training paradigm for improving HRPF in patients with IBD before guidelines can be developed and integrated into the therapeutic strategy. 展开更多
关键词 Inflammatory bowel disease Physical fitness ASSESSMENT INTERVENTION Physical activity EXERCISE
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A Robust Indoor Localization Algorithm Based on Polynomial Fitting and Gaussian Mixed Model 被引量:1
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作者 Long Cheng Peng Zhao +1 位作者 Dacheng Wei Yan Wang 《China Communications》 SCIE CSCD 2023年第2期179-197,共19页
Wireless sensor network(WSN)positioning has a good effect on indoor positioning,so it has received extensive attention in the field of positioning.Non-line-of sight(NLOS)is a primary challenge in indoor complex enviro... Wireless sensor network(WSN)positioning has a good effect on indoor positioning,so it has received extensive attention in the field of positioning.Non-line-of sight(NLOS)is a primary challenge in indoor complex environment.In this paper,a robust localization algorithm based on Gaussian mixture model and fitting polynomial is proposed to solve the problem of NLOS error.Firstly,fitting polynomials are used to predict the measured values.The residuals of predicted and measured values are clustered by Gaussian mixture model(GMM).The LOS probability and NLOS probability are calculated according to the clustering centers.The measured values are filtered by Kalman filter(KF),variable parameter unscented Kalman filter(VPUKF)and variable parameter particle filter(VPPF)in turn.The distance value processed by KF and VPUKF and the distance value processed by KF,VPUKF and VPPF are combined according to probability.Finally,the maximum likelihood method is used to calculate the position coordinate estimation.Through simulation comparison,the proposed algorithm has better positioning accuracy than several comparison algorithms in this paper.And it shows strong robustness in strong NLOS environment. 展开更多
关键词 wireless sensor network indoor localization NLOS environment gaussian mixture model(GMM) fitting polynomial
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Association between cardiorespiratory fitness level and insulin resistance in adolescents with various obesity categories 被引量:1
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作者 Lavinia La Grasta Sabolic Marija Pozgaj Sepec +1 位作者 Bernardica Valent Moric Maja Cigrovski Berkovic 《World Journal of Diabetes》 SCIE 2023年第7期1126-1136,共11页
BACKGROUND An association between cardiorespiratory fitness(CRF)and insulin resistance in obese adolescents,especially in those with various obesity categories,has not been systematically studied.There is a lack of kn... BACKGROUND An association between cardiorespiratory fitness(CRF)and insulin resistance in obese adolescents,especially in those with various obesity categories,has not been systematically studied.There is a lack of knowledge about the effects of CRF on insulin resistance in severely obese adolescents,despite their continuous rise.AIM To investigate the association between CRF and insulin resistance in obese adolescents,with special emphasis on severely obese adolescents.METHODS We performed a prospective,cross-sectional study that included 200 pubertal adolescents,10 years to 18 years of age,who were referred to a tertiary care center due to obesity.According to body mass index(BMI),adolescents were classified as mildly obese(BMI 100% to 120% of the 95^(th)percentile for age and sex)or severely obese(BMI≥120% of the 95^(th)percentile for age and sex or≥35 kg/m^(2),whichever was lower).Participant body composition was assessed by bioelectrical impedance analysis.A homeostatic model assessment of insulin resistance(HOMA-IR)was calculated.Maximal oxygen uptake(VO_(2)max)was determined from submaximal treadmill exercise test.CRF was expressed as VO_(2)max scaled by total body weight(TBW)(mL/min/kg TBW)or by fat free mass(FFM)(mL/min/kg FFM),and then categorized as poor,intermediate,or good,according to VO_(2)max terciles.Data were analyzed by statistical software package SPSS(IBM SPSS Statistics for Windows,Version 24.0).P<0.05 was considered statistically significant.RESULTS A weak negative correlation between CRF and HOMA-IR was found[Spearman’s rank correlation coefficient(rs)=-0.28,P<0.01 for CRF_(TBW);(r_(s))=-0.21,P<0.01 for CRF_(FFM)].One-way analysis of variance(ANOVA)revealed a significant main effect of CRF on HOMA-IR[F(2200)=6.840,P=0.001 for CRF_(TBW);F_((2200))=3.883,P=0.022 for CRF_(FFM)].Subsequent analyses showed that obese adolescents with poor CRF had higher HOMA-IR than obese adolescents with good CRF(P=0.001 for CRF_(TBW);P=0.018 for CRF_(FFM)).Two-way ANOVA with Bonferroni correction confirmed significant effect of interaction of CRF level and obesity category on HOMA-IR[F_((2200))=3.292,P=0.039 for CRF_(TBW)].Severely obese adolescents had higher HOMA-IR than those who were mildly obese,with either good or poor CRF.However,HOMA-IR did not differ between severely obese adolescents with good and mildly obese adolescents with poor CRF.CONCLUSION CRF is an important determinant of insulin resistance in obese adolescents,regardless of obesity category.Therefore,CRF assessment should be a part of diagnostic procedure,and its improvement should be a therapeutic goal. 展开更多
关键词 Cardiorespiratory fitness Insulin resistance Obese adolescents Severe obesity Obesity category
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Nintendo Wii Fit联合主动呼吸循环技术在老年慢阻肺的临床应用效果 被引量:1
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作者 李水文 姚琴 《医学理论与实践》 2023年第6期1059-1062,共4页
目的:研究Nintendo Wii Fit联合主动呼吸循环技术在老年慢阻肺(COPD)中的临床应用效果。方法:选取2020年6月—2021年7月在江西省贵溪市东信医院就诊的110例老年COPD患者作为观察对象,随机数表法分为实验组与对照组,各55例。对照组实施... 目的:研究Nintendo Wii Fit联合主动呼吸循环技术在老年慢阻肺(COPD)中的临床应用效果。方法:选取2020年6月—2021年7月在江西省贵溪市东信医院就诊的110例老年COPD患者作为观察对象,随机数表法分为实验组与对照组,各55例。对照组实施常规治疗和主动呼吸循环技术,试验组在对照组治疗方案基础上进行Nintendo Wii Fit运动训练干预,比较两组干预效果。结果:干预12周后实验组FVC、FEV_(1)、FEV_(1)/FVC、6MWT、握力测试、CAT和mMRC均显著优于对照组(P<0.001)。结论:Nintendo Wii Fit联合主动呼吸循环技术在老年COPD中的临床应用能改善肺功能、缓解呼吸困难、提升老年人身体素质与平衡水平、提高生活质量。 展开更多
关键词 NINTENDO Wii Fit COPD 运动训练 主动呼吸循环技术
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Look into my eyes:What can eye-based measures tell us about the relationship between physical activity and cognitive performance?
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作者 Liye Zou Fabian Herold +11 位作者 Sebastian Ludyga Keita Kamijo Notger G.Muller Matthew B.Pontifex Matthew Heath Ryuta Kuwamizu Hideaki Soya Charles H.Hillman Soichi Ando Brandon L.Alderman Boris Cheval Arthur F.Kramer 《Journal of Sport and Health Science》 SCIE CAS CSCD 2023年第5期568-591,共24页
Background:There is a growing interest to understand the neurobiological mechanisms that drive the positive associations of physical activity and fitness with measures of cognitive performance.To better understand tho... Background:There is a growing interest to understand the neurobiological mechanisms that drive the positive associations of physical activity and fitness with measures of cognitive performance.To better understand those mechanisms,several studies have employed eye-based measures(e.g., eye movement measures such as saccades,pupillary measures such as pupil dilation,and vascular measures such as retinal vessel diameter)deemed to be proxies for specific neurobiological mechanisms.However,there is currently no systematic review providing a comprehensive overview of these studies in the field of exercise-cognition science.Thus,this review aimed to address that gap in the literature.Methods:To identify eligible studies,we searched 5 electronic databases on October 23,2022.Two researchers independently extracted data and assessed the risk of bias using a modified version of the Tool for the assEssment of Study qualiTy and reporting in EXercise(TESTEX scale,for interventional studies) and the critical appraisal tool from the Joanna Briggs Institute(for cross-sectional studies).Results:Our systematic review(n=35 studies) offers the following main findings:(a) there is insufficient evidence available to draw solid conclusions concerning gaze-fixation-based measures;(b) the evidence that pupillometric measures,which are a proxy for the noradrenergic system,can explain the positive effect of acute exercise and cardiorespiratory fitness on cognitive performance is mixed;(c) physical training-or fitness-related changes of the cerebrovascular system(operationalized via changes in retinal vasculature) are,in general,positively associated with cognitive performance improvements;(d) acute and chronic physical exercises show a positive effect based on an oculomotor-based measure function(operationalized via antisaccade tasks);and(e) the positive association between cardiorespiratory fitness and cognitive performance is partly mediated by the dopaminergic system(operationalized via spontaneous eye-blink rate).Conclusion:This systematic review offers confirmation that eye-based measures can provide valuable insigt into the neurobiological mechanisms that may drive positive associations between physical activity and fitness and measures of cognitive performance.However,due to the limited number of studies utilizing specific methods for obtaining eye-based measures(e.g.,pupillometry,retinal vessel analysis,spontaneous eye blink rate) or investigating a possible dose-response relationship,further research is necessary before more nuanced conclusions can be drawn.Given that eye-based measures are economical and non-invasive,we hope this review will foster the future application of eye-based measures in the field of exercise-cognition science. 展开更多
关键词 COGNITION EXERCISE FITNESS Pupil size RetinaTagedAPTARAEnd
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