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Rider Optimization Algorithm Based Optimal Cloud Server Selection in E-Learning
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作者 R.Soundhara Raja Pandian C.Christopher Columbus 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1749-1762,共14页
Currently,e-learning is one of the most prevalent educational methods because of its need in today’s world.Virtual classrooms and web-based learning are becoming the new method of teaching remotely.The students exper... Currently,e-learning is one of the most prevalent educational methods because of its need in today’s world.Virtual classrooms and web-based learning are becoming the new method of teaching remotely.The students experience a lack of access to resources commonly the educational material.In remote loca-tions,educational institutions face significant challenges in accessing various web-based materials due to bandwidth and network infrastructure limitations.The objective of this study is to demonstrate an optimization and queueing tech-nique for allocating optimal servers and slots for users to access cloud-based e-learning applications.The proposed method provides the optimization and queue-ing algorithm for multi-server and multi-city constraints and considers where to locate the best servers.For optimal server selection,the Rider Optimization Algo-rithm(ROA)is utilized.A performance analysis based on time,memory and delay was carried out for the proposed methodology in comparison with the exist-ing techniques.The proposed Rider Optimization Algorithm is compared to Par-ticle Swarm Optimization(PSO),Genetic Algorithm(GA)and Firefly Algorithm(FFA),the proposed method is more suitable and effective because the other three algorithms drop in local optima and are only suitable for small numbers of user requests.Thus the proposed method outweighs the conventional techniques by its enhanced performance over them. 展开更多
关键词 Optimization QUEUING slot selection server selection rider optimization algorithm
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The Effects of Using a Specially Designed Stirrup on Kinetic Energy Absorption by the Knee Joint of 12 Show Jumping/Eventing Riders
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作者 Marta Kulikowska Franziska C. Wagner Adrian Harrison 《Open Journal of Veterinary Medicine》 CAS 2023年第2期13-21,共9页
The use of Winderen Knee Protection Solution stirrups compared to standard iron stirrups, reveals the following benefits: 1) A reduction of stress or strain time in the order of 14 seconds per minute of activity whils... The use of Winderen Knee Protection Solution stirrups compared to standard iron stirrups, reveals the following benefits: 1) A reduction of stress or strain time in the order of 14 seconds per minute of activity whilst walking and 5 - 7 seconds less whilst trotting or cantering for muscles around the knee. 2) A reduction of stress or strain time in the order of 25 seconds per minute of activity whilst walking and 9 - 10 seconds less whilst trotting or cantering for ligaments around the knee. 3) A significant improvement in the E-score (less time exposed to stress and shock) and ST-score (lower force around the knee) whilst walking. 4) A considerable improvement in rider comfort and feeling of leg stability (self-assessment) compared with the owners current stirrups, whilst riding. 展开更多
关键词 STIRRUPS Knee Stress Acoustic Myography riders
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BitTorrent系统中free riders的研究
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作者 于魁飞 程久军 +1 位作者 李玉宏 马建 《高技术通讯》 CAS CSCD 北大核心 2007年第3期238-242,共5页
针对BitTorent文件共享过程的特点,根据乐观疏通的思想,利用仿真实验分析了free riders对系统中其他类型的peers的下载进程的影响,给出了识别free riders的方法,提出了解决free riders问题的机制,并进行了仿真实验。结果表明:这种解决f... 针对BitTorent文件共享过程的特点,根据乐观疏通的思想,利用仿真实验分析了free riders对系统中其他类型的peers的下载进程的影响,给出了识别free riders的方法,提出了解决free riders问题的机制,并进行了仿真实验。结果表明:这种解决free riders问题的机制更好地激励了系统中的peers为系统做出贡献,从而获得利益;有效地控制了Bit-Torrent系统中的free riders,提高了系统的整体性能。 展开更多
关键词 对等网络(P2P) BITTORRENT free riders
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Fractional Rider Deep Long Short Term Memory Network for Workload Prediction-Based Distributed Resource Allocation Using Spark in Cloud Gaming 被引量:1
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作者 Koné Kigninman Désiré Kouassi Adlès Francis +3 位作者 Konan Hyacinthe Kouassi Eya Dhib Nabil Tabbane Olivier Asseu 《Engineering(科研)》 2021年第3期135-157,共23页
The modern development in cloud technologies has turned the idea of cloud gaming into sensible behaviour. The cloud gaming provides an interactive gaming application, which remotely processed in a cloud system, and it... The modern development in cloud technologies has turned the idea of cloud gaming into sensible behaviour. The cloud gaming provides an interactive gaming application, which remotely processed in a cloud system, and it streamed the scenes as video series to play through network. Therefore, cloud gaming is a capable approach, which quickly increases the cloud computing platform. Obtaining enhanced user experience in cloud gaming structure is not insignificant task because user anticipates less response delay and high quality videos. To achieve this, cloud providers need to be able to accurately predict irregular player workloads in order to schedule the necessary resources. In this paper, an effective technique, named as Fractional Rider Deep Long Short Term Memory (LSTM) network is developed for workload prediction in cloud gaming. The workload of each resource is computed based on developed Fractional Rider Deep LSTM network. Moreover, resource allocation is performed by fractional Rider-based Harmony Search Algorithm (Rider-based HSA). This Fractional Rider-based HSA is developed by combining Fractional calculus (FC), Rider optimization algorithm (ROA) and Harmony search algorithm (HSA). Moreover, the developed Fractional Rider Deep LSTM is developed by integrating FC and Rider Deep LSTM. In addition, the multi-objective parameters, namely gaming experience loss QE, Mean Opinion Score (MOS), Fairness, energy, network parameters, and predictive load are considered for efficient resource allocation and workload prediction. Additionally, the developed workload prediction model achieved better performance using various parameters, like fairness, MOS, QE, energy and delay. Hence, the developed Fractional Rider Deep LSTM model showed enhanced results with maximum fairness, MOS, QE of 0.999, 0.921, 0.999 and less energy and delay of 0.322 and 0.456. 展开更多
关键词 Cloud Computing rider Deep LSTM Fractional Calculus Workload Prediction Resource Allocation
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Investigation Motorcycle Safety at Exit Ramp Sections by Analyzing Historical Crash Data and Rider’s Perception
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作者 Hongyun Chen Chanyoung Lee Pei-Sung Lin 《Journal of Transportation Technologies》 2014年第1期107-115,共9页
The purpose of this study is to evaluate the safety performance of four exit ramp types and the major contributing factors on motorcycle crashes and injury severity of motorcycle riders. A six-year crash data were col... The purpose of this study is to evaluate the safety performance of four exit ramp types and the major contributing factors on motorcycle crashes and injury severity of motorcycle riders. A six-year crash data were collected in Florida, and a web-based survey (234 samples) was conducted. 573 crashes were found at 419 exits, including 178 diamond exits, 71 directional exits, 85 loop exits and 85 outer connection exits. For a diamond exit, both the survey and crash data showed that this type was safer and more preferable by motorcycle riders;while a loop exit was the most dangerous exit due to the sharp curve and a certain length of curve with limited visibility. For a directional exit, longer ramp lengths and the reverse curvature are the major factors causing motorcycle crashes. For an outer connection exit, the riders rated it as a safe type;however, the data showed higher average crash frequency and rate than those at diamond exits or directional exits. The possible reason could be the unexpected curvature in the middle of the ramp, which could be dangerous if the rider is not familiar with the exit ramp location or doesn’t pay attention to the ramp curvatures. The crash predictive model was developed, and the result indicated that if all remained the same, a directional exit, a loop exit, or an outer connection exit will have 16%, 27%, and 42% more crashes than a diamond exit, respectively. The findings from this study can help policy-makers and engineers to develop and apply effective countermeasures to reduce motorcycle crashes and injury severity levels for different exit ramp types. 展开更多
关键词 MOTORCYCLE SAFETY EXIT RAMP Configurations CRASH Modeling riders’ Survey
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Cultural Value of Ancient Chinese Terracotta Rider Figurines
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作者 CHAO Hong LU Chunli 《Journal of Landscape Research》 2016年第2期90-92,共3页
Terracotta rider fi gurines are common artifacts in the past, generally combinations of person riding animals like horse or camel, through these organic fi gures we can see vivid pictures of ancient social life and cu... Terracotta rider fi gurines are common artifacts in the past, generally combinations of person riding animals like horse or camel, through these organic fi gures we can see vivid pictures of ancient social life and cultural evolution. A lot of researches on terracotta fi gurines have been reported, but terracotta rider fi gurines have been less studied as an independent object. This paper studied terracotta rider fi gurines, and found that this cultural form originated from the Warring States Period, thrived in the Tang Dynasty, and declined gradually after the Yuan Dynasty. The declination of ancient terracotta rider fi gurine culture owes to the changing social environment in different historical periods. Researches on terracotta rider fi gurines explored social customs and conventions behind them, and provided signifi cant theoretical support for protecting the cultural heritage. 展开更多
关键词 Terracotta figurine Terracotta rider figurine Horse riding tradition
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The Use of Sputum Dashboard and Dispatch Riders in Mitigating Delay in Sputum Samples’ Processing—Evidence from an Intervention in Lagos State, Nigeria
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作者 Muse Olatunbosun Fadeyi Akinwumi Akindele +7 位作者 Adebayo Bakare Bolaji Ahmed Osman El-Tayeb Taofeekat Ali Yasir Othman Obioha Udunze Gbolahan Dairo Aderonke Agbaje 《Journal of Tuberculosis Research》 2021年第3期146-159,共14页
<span style="font-family:Verdana;">The act of referring TB presumptive individuals after verbal screening to another health facility/diagnostic centres for testing often results in large loss to follow... <span style="font-family:Verdana;">The act of referring TB presumptive individuals after verbal screening to another health facility/diagnostic centres for testing often results in large loss to follow-up, owing to the many barriers people face in accessing care. The transportation of sputum samples is an efficient method of increasing access to tuberculosis (TB) diagnostics in areas where testing is not currently available. One of the major reasons for the low yield of TB cases in the field was delay in sputum sample transportation to diagnostic laboratories among other factors. Damien Foundation Belgium, carried out a unique sputum riders initiatives in 20 LGAs of Lagos state between Q3-2019 and Q4-2020. A total of 25 sputum dispatch riders across the 20 LGAs in the State who are monitored routinely on an electronic dashboard were engaged for sputum logistics. Therefore, this report highlights how the initiatives ha</span><span style="font-family:Verdana;">ve </span><span style="font-family:Verdana;">contributed to increased TB case notification in a densely populated metropolitan city in Nigeria. </span><span style="font-family:Verdana;">Overall, </span><span style="font-family:Verdana;">48,265 units of sputum samples were transported to the laboratory from the facilities 99.9% of results </span><span style="font-family:Verdana;">which </span><span style="font-family:Verdana;">were received from the laboratory by the dispatch riders</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">The contribution of sputum riders to the overall TB case detection by the project progressively increased from 9% when the intervention began to 57% as at Q4 2020. The transportation of sputum samples by motorcycle dispatch riders is an efficient method of increasing access to TB diagnostic services in communities where testing is not currently available.</span> 展开更多
关键词 Sputum Samples Dispatch rider Electronic Dashboard Sputum Logistics TUBERCULOSIS
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Validation of a Low Cost Horse Saddle Stabilometric Platform to Analyze the Rider’s Balance
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作者 Dominique Prin-Conti William Bertucci Karl Debray 《Journal of Sports Science》 2019年第1期24-32,共9页
The purpose was to create a stabilometric platform to analyze the rider’s balance. After anatomical and saddle’s mark study, four bones support points representing the rider’s base were determined, that will allow ... The purpose was to create a stabilometric platform to analyze the rider’s balance. After anatomical and saddle’s mark study, four bones support points representing the rider’s base were determined, that will allow the construction of our rider posture diagnostic aid platform. The sensors profile was realized and the stirrups dynamometers were calibrated through an extensometry study. To validate by comparison with a stabilometric platform (OIML 6000 sensors), one series of 28 observations under the same conditions were carried out (the two platforms adjusted one on the other), statistical analyses on the X and Y axis were performed with normality distribution test (S-W), t test and non-parametric Wilcoxon-Mann-Whitney test (p-value > 0.05). To analyze our two methods of measuring the centre of pressure position, a Bland-Altman analysis has been plotted and the intra class correlation value computed. The Bland-Altman graph showed a small bias value (-0.4 ± 0.8mm) with acceptable limits of agreement for rider balance analyses. The results of the present study suggested that the new platform was accurate and reliable and could be used for further prospective studies in order to optimize the rider’s posture and preserve the horse’s health. 展开更多
关键词 LOW-COST new device rider BALANCE CENTRE of pressure stabilometric PLATFORM
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Prevalence and Predisposing Factors of Human Immunodeficiency Virus Infection among the Boda-Boda Riders in Mbarara Municipality-Uganda
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作者 Mathias Tumwebaze Emmanuel O. Otiam +1 位作者 Kakwezi Margaret Rukindo John Mwesigwa 《Open Journal of Epidemiology》 2020年第3期235-250,共16页
<strong>Background:</strong> Boda-Boda is a well-known and booming motorcycle taxi that employs youths to earn a living. They transport passengers at a faster rate where other means of transport are inacce... <strong>Background:</strong> Boda-Boda is a well-known and booming motorcycle taxi that employs youths to earn a living. They transport passengers at a faster rate where other means of transport are inaccessible or would be time consuming. Global statistics show that HIV has continued to be a major global Public Health issue especially among the “Most At-risk Populations” (MAPs) that include commercial transporters and Boda-Boda riders. <strong>Aim:</strong> This study aimed at assessing the prevalence and predisposing factors for HIV/AIDS among Boda-Boda riders living in Mbarara Municipality. Specifically, the study determined the prevalence of HIV among the Boda-Boda riders, identified social demographic predisposing factors for HIV and determined knowledge of Boda riders on prevention of HIV. <strong>Study setting:</strong> Boda-Boda operators in the transport sector are at high risk of HIV infection but the HIV status of the Boda Riders in Mbarara was not known a reason why the study was instituted: <strong>Study design:</strong> This was an analytical and descriptive cross-sectional study that employed quantitative methods of data collection. The study population comprised the registered Boda-Boda operators from two divisions of Kakoba and Kakiika in Mbarara municipality. <strong>Sample size and sampling methods:</strong> Using Morgan’s table (1970), the population of the registered Boda Riders was 15,041;this corresponded to a sample size of 375 respondents by Morgan Table. Systematic sampling procedure was used to get every 3rd registered rider on the list. <strong>Data collection:</strong> A pre-tested structured tool aided data collection after group pretest counseling. Individual counseling was also done prior to testing and giving results. The laboratory technologists drew blood to determine the sero-status of the respondents. Results were recorded as tested reactive (TRR) or tested non-reactive (TR). Unigold was used as tie breaker to confirm their diagnosis in order to ascertain those who were HIV positive on determine. <strong>Data analysis:</strong> Analysis was done at univariate, bivariate and multivariate using STATA version 13, Statistical significance of the relationship was determined for the p-value (p ≤ 0.05). Significant variables were then considered at multivariate level of analysis. <strong>Results:</strong> More than half 195 (52%) of the Boda-Boda cyclist had attained primary level of education and 36.5% secondary education. HIV prevalence among Boda-Boda riders was 9.9%. Riders who had never heard of VCT/HCT screening for HIV were three times likely to acquire HIV compared to those who ever heard of VCT/HCT screening (OR = 3.35;95% CI 1.14 9.83;p = 0.027). Those with multiple partners were six times more likely to acquire HIV/AIDS compared to those who buy sex from prostitutes (OR = 6.13;95% CI 1.54 24.38;p = 0.01). The level of awareness of VCT was found high at (94.7%), and the general knowledge about utilization and importance of VCT services was at 80%, however condom use as a preventive measure was found low at 44.3% among the respondent Boda-Boda riders. <strong>Conclusion:</strong> Boda-Boda riders had high HIV prevalence of 9.9% compared to that of Mbarara district at 6.1% and much higher than 5.7% national HIV prevalence level. The predisposing factors to acquire HIV/AIDS were having multiple sexual partners, not having heard of HIV counseling and testing as well as low and inconsistent condom use at 44.3%. The study recommends health service providers and HIV counselors to intensify awareness and behavior change campaigns on condom use among the Boda-Boda riders as preventive measure against HIV. 展开更多
关键词 Boda-Boda riders HIV Prevalence in Boda-Boda VCT/HCT Screening for HIV Condom Use
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霹雳游侠——Knight Rider 2008 Ford Shelby GT500KR
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作者 佳俊 《世界汽车》 北大核心 2008年第4期44-44,共1页
还记得儿时的一部电视剧吗?剧中主人公驾驶着一辆会说话的智能汽车奔驰在美国的大街小巷上,与层出不穷的邪恶势力英勇战斗。当时电视剧《霹雳游侠》让我们稚嫩的脑海中充满了幻想,我们经常幻想自己就是那个主人公,开着一辆会说话、会思... 还记得儿时的一部电视剧吗?剧中主人公驾驶着一辆会说话的智能汽车奔驰在美国的大街小巷上,与层出不穷的邪恶势力英勇战斗。当时电视剧《霹雳游侠》让我们稚嫩的脑海中充满了幻想,我们经常幻想自己就是那个主人公,开着一辆会说话、会思考,并且能成为朋友的汽车。 展开更多
关键词 游侠 Knight rider 2008 Ford Shelby GT500KR 查理斯
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P2P网络中Free-rider的平衡机制 被引量:1
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作者 李玉玲 刘玉华 +1 位作者 许凯华 潘华强 《计算机工程》 CAS CSCD 北大核心 2010年第22期111-112,115,共3页
针对P2P网络中出现的free-rider现象,提出一种控制点位于服务提供节点上的平衡机制。该机制充分考虑P2P网络拓扑结构不一致的问题,并允许一定数量的free-rider节点存在。实验证明,该机制既能有效利用网络资源,提高交易的成功率,又能对... 针对P2P网络中出现的free-rider现象,提出一种控制点位于服务提供节点上的平衡机制。该机制充分考虑P2P网络拓扑结构不一致的问题,并允许一定数量的free-rider节点存在。实验证明,该机制既能有效利用网络资源,提高交易的成功率,又能对严重的free-rider行为进行抑制。 展开更多
关键词 P2P网络 搭便车 效用值 平衡机制
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骑手出击:MIZUNO RIDER 11
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作者 最后的神 《中国服装(北京)》 2008年第2期52-53,共2页
在论坛上,跑鞋爱好者经常问到MIZUNO的哪款最好,MIZUNO给跑步者和潮流爱好者都提供了很多选择,然而,款式最经典、销量最高、适应人群最广的、各论坛出镜率最高的,还是RIDER系列。
关键词 MIZUNO rider 11 跑鞋 款式 功能 价格
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逍遥骑士easy rider
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作者 陈鹏 《摩托车信息》 2019年第7期66-67,共2页
1969年,《逍遥骑士》横空出世。这是一部充满惶惑、否定、叛逆和悲剧的存在主义式公路电影。《逍遥骑士》不仅是60年代美国垮掉运动的经典符号之一,更是开创新好莱坞黄金时代的分水岭。这部电影获得了奇迹般的成功,1969年获奥斯卡奖七... 1969年,《逍遥骑士》横空出世。这是一部充满惶惑、否定、叛逆和悲剧的存在主义式公路电影。《逍遥骑士》不仅是60年代美国垮掉运动的经典符号之一,更是开创新好莱坞黄金时代的分水岭。这部电影获得了奇迹般的成功,1969年获奥斯卡奖七项提名,同时在欧洲大受欢迎,在第22届戛纳电影节上,本片夺得了最佳处女作奖。它的奇迹还体现在票房上,本片投资40万美元,票房收入却高达2500万,难怪哥伦比亚公司要收购影片的版权,在当时,好莱坞大公司收买一部独立制片的小制作电影是不多见的。 展开更多
关键词 新好莱坞 EASY rider 公路电影
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China, Free Rider or Contributor?
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作者 ZHU FENG 《China Today》 2014年第10期16-17,共2页
IN an interview early last August with the New York Times,U.S.President Obama remarked that China had been a global free rider for the past 30 years,and that the U.S.does not expect China to do anything substantial in... IN an interview early last August with the New York Times,U.S.President Obama remarked that China had been a global free rider for the past 30 years,and that the U.S.does not expect China to do anything substantial in dealing with Iraq.Obama is in fact not the first to accuse China of being a free rider in the international community. 展开更多
关键词 rider interview dealing anything expect riding Deputy turmoil politics cooperation
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Analyzing Electric Bicycle Rider's Unsafe Crossing Behavior Based on Theory of Planned Behavior
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作者 Qingyuan Zhang Guoqiang Zhang Yuli Qi 《现代交通(中英文版)》 2013年第2期15-22,共8页
关键词 不安全行为 电动自行车 行为理论 骑士 道路运输系统 行为控制 交通安全意识 行车事故
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平台场域内中等收入人群“滑落”风险形成与治理机制——基于美团外卖骑手的案例研究 被引量:2
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作者 曲亮 包冰乐 《管理案例研究与评论》 北大核心 2024年第1期36-55,共20页
在中等收入人群绝对规模增加的过程中,也存在着“滑落”现象,以往对于中等收入人群的研究多从收入分配制度、人力资本等角度展开。通过美团案例的研究发现,中等收入人群“滑落”的根源为生态成员权责范围的模糊,“稳中”还需依赖平台治... 在中等收入人群绝对规模增加的过程中,也存在着“滑落”现象,以往对于中等收入人群的研究多从收入分配制度、人力资本等角度展开。通过美团案例的研究发现,中等收入人群“滑落”的根源为生态成员权责范围的模糊,“稳中”还需依赖平台治理。处于市场优势地位的美团,在供求失衡的市场机制和算法技术的支持下,通过灵活用工模式规避雇佣责任,但这种劳资关系并非稳定的和可持续的。外卖骑手可以通过自我赋能、维护自身主体性、多栖战略等途径抵御“滑落”,同时,制度缺口填补、平台与政府协同治理、平台企业垄断规制和多元主体赋权的方式也可以阻断外卖骑手的“滑落”通道。外卖骑手“滑落”是研究橄榄型社会结构构建的经典案例,对我国完善平台治理结构和发展共同富裕具有积极意义。 展开更多
关键词 中等收入人群 外卖骑手 “滑落”风险 平台治理理论
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平台梯度计酬制度与外卖骑手的过度劳动行为——基于剥削感知中介效应的检验 被引量:1
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作者 周蕾 宫月 《山东工会论坛》 2024年第1期11-20,共10页
平台经济的迅猛发展催生了外卖骑手这一新就业形态从业群体,但外卖平台通过计酬体系和奖惩制度影响外卖骑手决策,甚至引发过度劳动问题。文章基于南京市1186名外卖骑手的相关数据,研究平台梯度计酬制度对骑手过度劳动行为的影响,并探讨... 平台经济的迅猛发展催生了外卖骑手这一新就业形态从业群体,但外卖平台通过计酬体系和奖惩制度影响外卖骑手决策,甚至引发过度劳动问题。文章基于南京市1186名外卖骑手的相关数据,研究平台梯度计酬制度对骑手过度劳动行为的影响,并探讨骑手剥削感知在其中的中介作用。实证分析发现:梯度奖励幅度一方面直接正向影响骑手的过度劳动程度,另一方面通过降低剥削感知这一中介变量而间接影响过度劳动程度,即梯度奖励幅度越高,骑手剥削感知越弱,骑手的过度劳动状况越明显。因此,应建立外卖行业劳动定额并加强平台劳动监管,以保障骑手劳动权益、规范平台经济环境与促进新业态经济健康发展。 展开更多
关键词 过度劳动 梯度计酬制度 外卖骑手 剥削感知
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马术骑手髋腰部慢性损伤的影像学和生物力学分析
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作者 何俊良 程克强 +1 位作者 孙琪 邵明昊 《医用生物力学》 CAS CSCD 北大核心 2024年第1期151-156,共6页
目的 通过分析专业马术骑手腰椎及髋关节影像学和表面肌电信息,了解马术骑手髋部和腰部慢性疾病发病率,探究骑手慢性疼痛的发病原因。方法 选取25名上海市马术运动管理中心马术骑手,按照病史分为慢性腰部疼痛组和慢性髋部疼痛组。同时选... 目的 通过分析专业马术骑手腰椎及髋关节影像学和表面肌电信息,了解马术骑手髋部和腰部慢性疾病发病率,探究骑手慢性疼痛的发病原因。方法 选取25名上海市马术运动管理中心马术骑手,按照病史分为慢性腰部疼痛组和慢性髋部疼痛组。同时选取12名无髋腰部疼痛普通人作为对照组,收集受试者髋腰部相关病史资料和髋腰部X线、磁共振成像及核心肌群表面肌电数据。结果 慢性腰痛者腰椎JOA评分明显低于对照组(P<0.05)。骑手慢性髋关节疼痛相对较轻,但Harris评分明显低于对照组(P<0.05)。马术骑手腰部JOA评分与Pfirrmann分级明显相关。而髋部疼痛视觉模拟评分和Harris评分与影像学参数无明显相关性。腹直肌、竖脊肌、股直肌、臀中肌和多裂肌在骑坐姿势的均方根振幅大于正常坐位(P<0.05)。结论 马术骑手的慢性腰部疼痛发病原因主要可能与软组织过度劳损和腰椎退变相关;腰-髋矢状位序列骨盆倾斜角和骶骨倾斜角的变化可以反映马术骑手腰部僵硬程度。 展开更多
关键词 马术骑手 髋腰部损伤 慢性损伤 影像学检查 生物力学
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外卖平台在线订单分配及骑手调度优化
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作者 王新玉 唐加福 +1 位作者 赵志明 张琪 《系统工程学报》 CSCD 北大核心 2024年第5期724-734,共11页
新兴技术(大数据/人工智能/移动互联网等)的发展和本地生活服务O2O(Online to Offline)商业模式兴起,催生了即时配送新兴物流形态,而外卖配送平台线上强履约要求成为即时配送业务痛点之一.考虑了实时外卖订单和动态变化的骑手等因素,将... 新兴技术(大数据/人工智能/移动互联网等)的发展和本地生活服务O2O(Online to Offline)商业模式兴起,催生了即时配送新兴物流形态,而外卖配送平台线上强履约要求成为即时配送业务痛点之一.考虑了实时外卖订单和动态变化的骑手等因素,将问题建模为带取送约束和时间约束的实时车辆调度优化问题.基于滚动时域机制将连续时间的动态问题划分为一系列离散静态子问题,设计了邻域搜索启发式算法进行求解.最后,基于大连市某外卖平台的订单业务数据对算法进行了验证,与已有文献中的方法相比,算法能有效降低平均配送时间及超时订单数量,在大规模问题场景下求解算法对平台履约影响更大,高效的调度优化算法有利于外卖平台降本增效. 展开更多
关键词 外卖平台 在线订单分配 骑手调度优化
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基于三方演化博弈的外卖骑手违规驾驶协同治理研究
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作者 耿纪超 李雪 杨力 《衡阳师范学院学报》 2024年第3期108-119,共12页
近年来,外卖已成为了大城市年轻人首选的用餐方式。由于消费者对快速送达的需求、平台企业对订单准时率的追求,外卖骑手不得不加快自己的送餐速度,导致违规驾驶,交通事故屡屡发生。为了科学、系统治理外卖人员的违规驾驶问题,本文设计... 近年来,外卖已成为了大城市年轻人首选的用餐方式。由于消费者对快速送达的需求、平台企业对订单准时率的追求,外卖骑手不得不加快自己的送餐速度,导致违规驾驶,交通事故屡屡发生。为了科学、系统治理外卖人员的违规驾驶问题,本文设计平台监管惩罚、商家规范出餐、骑手规范驾驶的合作机制,构建外卖平台、商家、骑手之间的三方演化博弈模型,分析三方主体策略选择和博弈系统均衡点的稳定性,并结合数值仿真方法考察不同参数取值对三方主体演化稳定策略的影响。最后,以企业、商家、骑手三方协同治理为抓手,针对配送机制、商家环境和政府治理等方面提出相关对策建议,形成利益三方共享,矛盾问题三方联调的良性互动。 展开更多
关键词 外卖配送 骑手安全 三方演化博弈 协同治理
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