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Experimental Research on Boundary Shear Stress in Typical Meandering Channel

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China Ocean Engineering 2018年第3期32卷 365-373页

作者： CHEN Kai-hua xia yun-feng ZHANG Shi-zhao WEN yun-cheng XU Hua Nanjing Hydraulic Research Institute Nanjing 210029China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China The State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210098China Key Laboratory of Port Waterway and Sedimentation Engineering of Ministry of TransportNanjing 210024China

A novel instrument named Micro-Electro-Mechanical System(MEMS) flexible hot-film shear stress sensor was used to study the boundary shear stress distribution in the generalized natural meandering open channel, and the mean sidewall shear stress distribution along the meandering channel, and the lateral boundary shear stress distribution in the typical cross-section of the meandering channel was analysed. Based on the measurement of the boundary shear stress, a semi-empirical semi-theoretical computing approach of the boundary shear stress was derived including the effects of the secondary flow, sidewall roughness factor, eddy viscosity and the additional Reynolds stress, and more importantly, for the first time, it combined the effects of the cross-section central angle and the Reynolds number into the expressions. Afterwards, a comparison between the previous research and this study was developed. Following the result, we found that the semi-empirical semi-theoretical boundary shear stress distribution algorithm can predict the boundary shear stress distribution precisely. Finally, a single factor analysis was conducted on the relationship between the average sidewall shear stress on the convex and concave bank and the flow rate, water depth, slope ratio,or the cross-section central angle of the open channel bend. The functional relationship with each of the above factors was established, and then the distance from the location of the extreme sidewall shear stress to the bottom of the open channel was deduced based on the statistical theory.

关键词： boundary shear stress flume physical model river bend MEMS flexible hot-film shear stress sensor

Justice in the Organizational Context： How Does Rating Disagreement Matter？

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Frontiers of Business Research in China 2013年第4期7卷 561-580页

作者： yun-xia feng Jun Liu School of Business Renmin University of China Beijing 100872 China Research Center for Corporate Innovation & Competitiveness (RCCIC) and School of Business Renmin University of China Beijing 100872 China

Since managers and employees play unequal roles in organizations, they have different perceptions regarding managerial practices. Understanding such differences and investigating the underlying causes help improve business administration and motivate organizational members. Employing data obtained from a sample of large SOEs （state owned enterprises）, this study evaluates disagreement between managers and employees in terms of their perception of organizational justice. Plausible causes of the disagreement and managerial implications are offered.

关键词： organizational justice perception rating disagreement structural equation modeling

Character Variable Numeralization Based on Dimension Expanding and its Application on Text Classification

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国际计算机前沿大会会议论文集 2016年第1期 62-64页

作者： Li-xun Xu Xu Yu Yong Wang yun-xia feng Sino-German Faculty Qingdao University of Science and TechnologyQingdao266061China School of Information Science and Technology Qingdao University of Science and TechnologyQingdao266061China College of Computer Science and Technology Harbin Engineering UniversityHarbin150001China

The character variable discrete numeralization destroyed the disorder of character variables. As text classification problem contains more character variable, discrete numeralization approach affects the classification performance of classifiers. In this paper, we propose a character variable numeralization algorithm based on dimension expanding. Firstly, the algorithm computes the number of different values which the character variable takes. Then it replaces the original values with the natural bases in the m-dimensional Euclidean space. Though the algorithm causes a dimension expanding, it reserves the disorder of character variables because the natural bases are no difference in size, so this algorithm is a better character variable numerical processing algorithm. Experiments on text classification data sets show that though the proposed algorithm costs a little more running time, its classification performance is better.

关键词： Character variable Natural bases Dimension expanding Text classification

Performance of the PRISM I,PIM2,PELOD-2 and PRISM IV scoring systems in western China:a multicenter prospective study

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World Journal of Pediatrics 2022年第12期18卷 818-824页

作者： Xue-Peng Zhang yun-xia feng Yang Li Guo-Yan Lu Xin-Yue Zhou Can-Zheng Wei Xi-Ying Gui Kai-Ying Yang Tong Qiu Jiang-Yuan Zhou Hua Yao Geng Zhang Wen-Qi Zhang Yu-Hang Hu Hong Wu Si-Yuan Chen Yi Ji Department of Pediatric Surgery West China Hospital of Sichuan UniversityChengdu610041China Department of Critical Care Medicine West China Hospital of Sichuan UniversityChengdu610041China Department of Nephrology Mianyang Central HospitalUniversity of Electronic Science and Technology of ChinaMianyang621000China Department of Pediatric Critical Care Medicine West China Women’s and Children’s HospitalSichuan UniversityChengdu610041China Department of Pediatric Critical Care Medicine Sichuan Provincial Maternity and Child Health Care HospitalChengdu610041China Department of Critical Care Medicine People’s Hospital of Tibet Autonomous RegionLhasa850000China Department of Anesthesiology the Affiliated Hospital of Guizhou Medical UniversityGuiyang550001China Department of Critical Care Medicine Mianyang Central HospitalUniversity of Electronic Science and Technology of ChinaMianyang621000China

Background The aim of this study was to evaluate the performance of the four scoring tools in predicting mortality in pediatric intensive care units(PICUs)in western *** This was a multicenter,prospective,cohort study conducted in six PICUs in western *** performances of the scoring systems were evaluated based on both discrimination and *** was assessed by calculating the area under the receiver operating characteristic curve(AUC)for each *** was measured across defined groups based on mortality risk using the Hosmer-Lemeshow goodness-of-fit *** A total of 2034 patients were included in this study,of whom 127(6.2%)*** the entire cohort,AUCs for Pediatric Risk of Mortality Score(PRISM)I,Pediatric Index of Mortality 2(PIM2),Pediatric Logistic Organ Dysfunction Score-2(PELOD-2)and PRISM IV were 0.88[95%confidence interval(CI)0.85–0.92],0.84(95%CI 0.80–0.88),0.80(95%CI 0.75–0.85),and 0.91(95%CI 0.88–0.94),*** Hosmer-Lemeshow goodness-of-fit Chi-square value was 12.71(P=0.12)for PRISM I,4.70(P=0.79)for PIM2,205.98(P<0.001)for PELOD-2,and 7.50(P=0.48)for PRISM IV[degree of freedom(df)=8].The standardized mortality ratios obtained with the PRISM I,PIM2,PELOD-2,and PRISM IV models were 0.87(95%CI,0.75–1.01),0.97(95%CI,0.85–1.12),1.74(95%CI,1.58–1.92),and 1.05(95%CI,0.92–1.21),*** PRISM IV performed best and can be used as a prediction tool in PICUs in Western ***,PRISM IV needs to be further validated in NICUs.

关键词： Illness severity score Intensive care Mortality prediction Pediatric

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抑郁状态与透析患者的心脑血管事件

中国血液净化 2020年第12期19卷 840-842页

作者：沈琳夏运风重庆医科大学附属第一医院肾内科重庆400016

抑郁状态是维持性血液透析(maintenance hemodialysis,MHD)患者最常见的心理异常表现,其发病率达MHD患者的20%~30%,是患者发生心脑血管事件及很多并发症的危险因素,严重影响患者的生活质量及预后。心脑血管事件是MHD患者的常见并发症,... 详细信息

抑郁状态是维持性血液透析(maintenance hemodialysis,MHD)患者最常见的心理异常表现,其发病率达MHD患者的20%~30%,是患者发生心脑血管事件及很多并发症的危险因素,严重影响患者的生活质量及预后。心脑血管事件是MHD患者的常见并发症,也是导致患者死亡的主要原因。现将MHD患者抑郁、心脑血管事件的发生情况及其相互联系综述如下,希望为相关的临床干预提供科学指导。

关键词：维持性血液透析抑郁心脑血管事件相关性

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资本市场中会计信息消费者结构的比较研究

财经理论与实践 2005年第5期26卷 37-40页

作者：夏云峰刘娜湘潭大学商学院湖南湘潭411105

通过对中外会计信息消费结构的比较可以发现,实施虚假消费的会计信息消费者倾向于与会计信息生产者合谋,侵占其他会计信息消费者的利益。优化会计信息消费者结构就是要找出具有强烈消费需求动力的会计信息消费者,促使其成熟,扩大他们的... 详细信息

通过对中外会计信息消费结构的比较可以发现,实施虚假消费的会计信息消费者倾向于与会计信息生产者合谋,侵占其他会计信息消费者的利益。优化会计信息消费者结构就是要找出具有强烈消费需求动力的会计信息消费者,促使其成熟,扩大他们的消费影响力。

关键词：资本市场会计信息消费者结构会计信息消费

Research on Measurement of Bed Shear Stress Under Wave-Current Interaction

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China Ocean Engineering 2015年第4期29卷 589-598页

作者：徐华夏云峰马炳和郝思禹张世钊杜德军 Nanjing Hydraulic Research Institute College of Harbor Coastal and Offshore Engineering Hohai University The State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering Waterway and Sediment Engineering of the Ministry of Communications Northwestern Polytechnical University

The movement of sediment in estuary and on coast is directly restricted by the bed shear stress. Therefore, the research on the basic problem of sediment movement by the bed shear stress is an important way to research the theory of sediment movement. However, there is not a measuring and computing method to measure the bed shear stress under a complicated dynamic effect like wave and current. This paper describes the measurement and test research on the bed shear stress in a long launder of direct current by the new instrument named thermal shearometer based on micro-nanotechnology. As shown by the research results, the thermal shearometer has a high response frequency and strong stability. The measured results can reflect the basic change of the bed shear stress under wave and wave-current effect, and confirm that the method of measuring bed shear stress under wave-current effect with thermal shearometer is feasible. Meanwhile, a preliminary method to compute the shear stress compounded by wave-current is put forward according to the tested and measured results, and then a reference for further study on the basic theory of sediment movement under a complicated dynamic effect is provided.

关键词： bed shear stress micro-nanotechnology thermal shearometer wave-current effect sediment movement

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-xia Dong yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

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福姜沙水道深水航道整治思路及工程布置

水运工程 2014年第7期 1-7页

作者：吴道文夏云峰南京水利科学研究院江苏南京210024

福姜沙河段目前呈三汊通航趋势,海轮航道走福南水道,江轮航道走福中水道,福北水道—如皋中汊为地方专用航道,目前三汊水深条件都不满足12.5 m深水航道要求尺度,为此必须进行整治。分析各汊道碍航情况及各汊道整治难度。针对各汊道碍航特... 详细信息

福姜沙河段目前呈三汊通航趋势,海轮航道走福南水道,江轮航道走福中水道,福北水道—如皋中汊为地方专用航道,目前三汊水深条件都不满足12.5 m深水航道要求尺度,为此必须进行整治。分析各汊道碍航情况及各汊道整治难度。针对各汊道碍航特性,提出整治原则及整治思路,在分析各汊道分流格局、水深条件、碍航特性等的基础上,提出整治工程平面布置形式。

关键词：深水航道整治思路布置形式