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电子商务平台中刷单行为对商家间竞争的影响

系统工程理论与实践 2021年第11期41卷 2876-2886页

作者：鲍立江仲伟俊梅姝娥东南大学经济管理学院南京210096

刷单成为电子商务平台中商家恶性竞争的工具之一.商家通过刷单制造虚假销量影响消费者的购买决策,从而影响商家之间的竞争.本文利用两阶段博弈模型分析了电子商务平台中刷单行为对两个商家竞争的影响.研究结果表明,市场中只有一个商家... 详细信息

刷单成为电子商务平台中商家恶性竞争的工具之一.商家通过刷单制造虚假销量影响消费者的购买决策,从而影响商家之间的竞争.本文利用两阶段博弈模型分析了电子商务平台中刷单行为对两个商家竞争的影响.研究结果表明,市场中只有一个商家进行刷单,同时,刷单成本较高时,刷单商家能够通过刷单获益;刷单成本较低时,不刷单商家反而能够从刷单商家的刷单行为收益.所以,即使电商平台提高刷单成本,仍不能完全抑制商家刷单.两个商家同时刷单,刷单成本较高时,高"价值-成本差"的商家刷单行为更加激进并能够获得更多收益;刷单成本较低时,低"价值-成本差"的商家刷单行为更加激进并能够获得更多收益;刷单成本更低时,低"价值-成本差"的商家刷单行为更加激进但收益受到伤害.由此,电商平台需要在高刷单成本下重点监控高"价值-成本差"商家,在低刷单成本下重点监控低"价值-成本差"商家.此外,商家在选择刷单策略时,刷单成本很低时,会陷入囚徒困境;而刷单成本较高时,二者将同时减少刷单并从中获利.因而,电商平台适度提高刷单成本对商家非但无害,反而有利.

关键词：刷单点击欺诈电子商务商业竞争

Reliability Analysis of a Switched Reluctance Starter/Generator

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Protection and Control of Modern Power Systems 2024年第1期9卷 112-121页

作者： Hao Chen Fan Yang Lijun Xu Qiwei Lu Xiqiang Chang Xing Wang lijiang Dong Yi Wen Jiang Chen Gang Miao Jianmin Hu Guanjun Wang Wei Li Xiaohua bao School of Electrical Engineering China University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China International Joint Research Center of Central and Eastern European Countries on New Energy Electric Vehicle Technology and Equipment Xuzhou 221008China International Cooperation Joint Laboratory of New Energy Power Generation and Electric Vehicles of Jiangsu Province Colleges and Universities Xuzhou 221008China School of Information and Electrical Engineering China University of Mining and TechnologyXuzhouChina China University of Mining and Technology(Beijing) BeijingChina State Grid Xingjiang Electric Power Co. Ltd.UrumqiXinjiangChina China University of Mining and Technology XuzhouChina State Grid Xinjiang Company Limited Electric Power Research Institute UrumqiXinjiangChina Xinjiang Fukang Pumped Storage Power Company Limited UrumqiXinjiangChina State Grid Urumqi Electric Power Supply Company UrumqiXinjiangChina Wuxi Inspection and Testing Certification Research Institute WuxiJiangsuChina Anhui Wannan Electric Machine Co. Ltd.WannanAnhuiChina Hefei University of Technology in Electrical and Automation Engineering

In this paper,the combined k-out-of-n:G model and reliability block diagram model is used to analyze the reliability of a switched reluctance starter/generator ***,the different operational modes of a switched reluctance motor starter/generator are analyzed,and the fault states of the system are briefly *** the fault criteria of the system in different operational states are put ***,a relia-bility block diagram model is established to calculate the system-level reliability,and the k-out-of-n:G model is adopted to analyze the reliability of each part of the switched reluctance starter/generator *** verify effectiveness,the first-order Markov model is also used to analyze the reliability of each part of the switched reluc-tance starter/generator *** the compu-tational complexity and accuracy of the system,the k-out-of-n:G model is more suitable for system component level reliability ***,a 6/4 switched reluctance motor is used as the simulated and experimental platform *** final results verify the effectiveness of the reliability analysis model.

关键词： system switched generator

Metabolic and transcriptomic analyses elucidate a novel insight into the network for biosynthesis of carbohydrate and secondary metabolites in the stems of a medicinal orchid Dendrobium nobile

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Plant Diversity 2023年第3期45卷 326-336页

作者： Yu-Wen Zhang Yu-Cen Shi Shi-bao Zhang Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Yunnan Key Laboratory for Wild Plant Resources Kunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang 674100YunnanChina

Dendrobium nobile is an important medicinal and nutraceutical *** the ingredients of *** have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is ***,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of ***.A total of 1005 metabolites and 31,745 genes were detected in the stems of *** majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid *** analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite *** analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid *** regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.

关键词： Dendrobium nobile Transcriptome Metabolome Polysaccharides Alkaloids Secondary metabolite biosynthesis

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纺织品中全氟己烷磺酸及其盐类测定方法研究

针织工业 2023年第7期 86-90页

作者：卢金保琦蓓程利江于纪棉宁波卫生职业技术学院浙江宁波315100

基于REACH法规将全氟己烷磺酸及其盐类(PFHxS)列为高度关注物质SVHC清单,限量为0.1%,开展试验室全氟己烷磺酸及其盐类的测定方法研究非常必要。文章采用制备的阳性样品建立了高效液相色谱-串联质谱(HPLC-MS/MS)分析方法,对纺织品中PFHx... 详细信息

基于REACH法规将全氟己烷磺酸及其盐类(PFHxS)列为高度关注物质SVHC清单,限量为0.1%,开展试验室全氟己烷磺酸及其盐类的测定方法研究非常必要。文章采用制备的阳性样品建立了高效液相色谱-串联质谱(HPLC-MS/MS)分析方法,对纺织品中PFHxS的含量进行测定。结果表明,该测定方法的定量下限为0.03 mg/kg,在3个加标浓度水平下平均加标回收率为91.8%~97.4%,相对标准偏差(RSD)为2.60%~7.50%,该方法操作简便、科学适用、定量下限远低于REACH法规的限量要求,可用于纺织品中PFHxS含量的日常检测。

关键词：纺织品全氟己烷磺酸及其盐类高效液相色谱-串联质谱法定量限

采用杠杆定位手法结合电磁经络通治疗腰椎间盘突出症的临床疗效分析

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高电压技术 2014年第12期40卷 3755-3761页

作者：吕立江包家立朱朝阳王晓东范炳华应晓明浙江中医药大学附属第三医院推拿科杭州310005 浙江大学医学院浙江省生物电磁学重点实验室生物物理与医学工程研究组杭州310058

为比较杠杆定位扳法结合电磁经络通与电磁经络通单独治疗腰椎间盘突出症（LDH）的疗效,以233例住院患者作为研究对象进行了统计比较。被观察患者包括男127例、女106例,年龄在18~72岁之间,其中50岁以上39例;患者病症包括膨出型97例、突出... 详细信息

为比较杠杆定位扳法结合电磁经络通与电磁经络通单独治疗腰椎间盘突出症（LDH）的疗效,以233例住院患者作为研究对象进行了统计比较。被观察患者包括男127例、女106例,年龄在18~72岁之间,其中50岁以上39例;患者病症包括膨出型97例、突出型85例、游离型51例。将患者按随机数字表法分为结合组（118例）和对照组（115例）。结合组采用杠杆定位扳法结合电磁经络通仪中的频脉冲电场对患者进行治疗;对照组采用电磁经络通仪单独进行治疗。观察患者症状和体征的指标积分,并按《中医病症诊断疗效标准》比较了2种方法治疗效果的差异。结果表明,治疗1个疗程后,结合组的症状与体征明显优于对照组（统计学中P〈0.001）。因此采用杠杆定位扳法结合电磁经络通治疗腰椎间盘突出症可以取得更好的疗效。

关键词：脉冲电场电磁经络通正骨手法椎间盘突出症腰椎临床观察

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汽车差动继动阀压铸结构工艺优化研究

热加工工艺 2016年第7期45卷 117-119页

作者：鲍家华周辉段立江吕俊杰应富强浙江工业大学浙江省特种装备制造与先进加工技术重点实验室浙江杭州310014

针对浙江某企业汽车差动继动阀产品合格率较低的问题,本文利用专业模流分析软件Procast对产品现有的压铸结构工艺进行数值模拟研究,观察铸件充型过程和模拟结果,分析缺陷成因。以此为依据,对原铸件压铸结构进行优化设计。结果表明:改进... 详细信息

针对浙江某企业汽车差动继动阀产品合格率较低的问题,本文利用专业模流分析软件Procast对产品现有的压铸结构工艺进行数值模拟研究,观察铸件充型过程和模拟结果,分析缺陷成因。以此为依据,对原铸件压铸结构进行优化设计。结果表明:改进后的铸件毛坯结构能改善该产品的缺陷问题,提高其合格率。

关键词：差动继动阀 Procast 压铸结构工艺合格率

河流风景区生态系统健康评价研究——以桂林漓江风景区为例

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自然灾害学报 2015年第2期24卷 122-127页

作者：鲍青青粟维斌桂林旅游高等专科学校旅游交通运营与服务系广西桂林541006 广西旅游科学研究所广西桂林541006

基于河流风景区生态系统特征及功能分析,提出了河流风景区生态系统健康的概念,并结合PSR评价框架和河流风景区生态系统的特点,建立了河流风景区生态系统健康评价模型。在此基础上,利用漓江风景区2002-2011年间10a的相关数据,对漓江风景... 详细信息

基于河流风景区生态系统特征及功能分析,提出了河流风景区生态系统健康的概念,并结合PSR评价框架和河流风景区生态系统的特点,建立了河流风景区生态系统健康评价模型。在此基础上,利用漓江风景区2002-2011年间10a的相关数据,对漓江风景区生态系统健康状况进行了评价。结果显示:漓江风景区生态系统总体健康状况逐年好转,但其压力评价要素长期处于亚健康至疾病状态。针对生态环境压力,从4个方面提出了加强桂林漓江风景区生态系统健康管理的措施。

关键词：河流风景区生态系统健康评价漓江风景名胜区

High-resolution visible imaging with piezoelectric deformable secondary mirror: experimental results at the 1.8-m adaptive telescope

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Opto-Electronic Advances 2023年第12期6卷 15-26页

作者： Youming Guo Kele Chen Jiahui Zhou Zhengdai Li Wenyu Han Xuejun Rao Hua bao Jinsheng Yang Xinlong Fan Changhui Rao The Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China University of Chinese Academy of Sciences Beijing 100049China School of Electronic Electrical and Commutation EngineeringUniversity of Chinese Academy of ScienceBeijing 100049China National Key Laboratory of Optical Field Manipulation Science and Technology Chengdu 610209China.

Integrating deformable mirrors within the optical train of an adaptive telescope was one of the major innovations in astronomical observation technology,distinguished by its high optical throughput,reduced optical surfaces,and the incorporation of the deformable ***,voice-coil actuators are used,which require additional position sensors,internal control electronics,and cooling systems,leading to a very complex *** deformable secondary mirror technologies were proposed to overcome these ***,a high-order piezoelectric deformable secondary mirror has been developed and installed on the 1.8-m telescope at lijiang Observatory in China to make it an adaptive *** system consists of a 241-actuator piezoelectric deformable secondary mirror,a 192-sub-aperture Shack-Hartmann wavefront sensor,and a multi-core-based real-time *** actuator spacing of the PDSM measures 19.3 mm,equivalent to approximately 12.6 cm when mapped onto the primary mirror,significantly less than the voicecoil-based adaptive telescopes such as LBT,Magellan and *** a result,stellar images with Strehl ratios above 0.49 in the R band have been *** our knowledge,these are the highest R band images captured by an adaptive telescope with deformable secondary ***,we report the system description and on-sky performance of this adaptive telescope.

关键词： adaptive optics deformable secondary mirror visible imaging

市县级政策与管理在古村落保护和旅游中的重要性——以黄山市、大理州和丽江市为例

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建筑学报 2006年第12期 45-47页

作者：车震宇保继刚昆明理工大学建筑学系昆明650224 中山大学旅游发展与规划研究中心广州510275

在古村落保护和旅游中,由于国家级和省级的农村建房、村落保护和土地使用政策存在一些争论条例和“模糊地带”,这些政策在执行过程中产生的矛盾都集中于市县级政府。市县级政府面对各种矛盾的调解与利益的得失,结合当地实际和自身利益,... 详细信息

在古村落保护和旅游中,由于国家级和省级的农村建房、村落保护和土地使用政策存在一些争论条例和“模糊地带”,这些政策在执行过程中产生的矛盾都集中于市县级政府。市县级政府面对各种矛盾的调解与利益的得失,结合当地实际和自身利益,施行不同的市县级政策和管理,这对指导村民和开发商如何修建和保护房屋起到了关键作用,并最终影响到村落形象和村落旅游。

关键词：政策管理村落旅游村落保护