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Environmental risk assessment of the middle route of south-to-north water transferring source project in China
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作者 Wang Huadong Wang Fei(Institute of Environmental Sciences,Beijing Normal University, Beijing 100875, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第3期285-291,共7页
This paper focused on the environment risk of the middle route of south-to-north water transferring source project in China. Analytic hierarchy process was applied to risk identification,fuzzy probability-fault tree ... This paper focused on the environment risk of the middle route of south-to-north water transferring source project in China. Analytic hierarchy process was applied to risk identification,fuzzy probability-fault tree analysis to risk probability assessment,statistics and analogy process to risk consequences assessment, lastly, grey relevant analysis and comprehensive index process to risk impact evaluation. The main environment risk accident of the project is dam failure, the main causative factors of the accident are catastrophic flood and wrecking earthquake. The flash flood, due to dam failure, will impact on nature, society and economy. The major environment risk areas are Jingzhou and Xiangfan,Hubei Province. The environment risk management measures should be adopted in order to ensure the safety of the project-environment complex system. 展开更多
关键词 water source project environment risk risk assessment
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Seasonal differences in climatic controls of vegetation growth in the Beijing–Tianjin Sand Source Region of China 被引量:1
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作者 SHAN Lishan YU Xiang +3 位作者 SUN Lingxiao HE Bin WANG Haiyan XIE Tingting 《Journal of Arid Land》 SCIE CSCD 2018年第6期850-863,共14页
Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in v... Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of this project. Precipitation and essential climate variable-soil moisture (ECV-SM) conditions are typically considered to be the main drivers of vegetation growth in this region. Although many studies have investigated the inter-annual variations of vegetation growth, few concerns have been focused on the annual and seasonal variations of vegetation growth and their climatic drivers, which are crucial for understanding the relationships among the climate, vegetation, and human activities at the regional scale. Based on the normalized difference vegetation index (NDVI) derived from MODIS and the corresponding climatic data, we explored the responses of vegetation growth to climatic factors at annual and seasonal scales in the BTSSCP region during the period 2000–2014. Over the study region as a whole, NDVI generally increased from 2000 to 2014, at a rate of 0.002/a. Vegetation growth is stimulated mainly by the elevated temperature in spring, whereas precipitation is the leading driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. The warming in spring promotes vegetation growth but reduces ECV-SM. Summer greening has a strong cooling effect on land surface temperature. These results indicate that the ecological and environmental consequences of ecological restoration projects should be comprehensively evaluated. 展开更多
关键词 vegetation growth climatic drivers seasonal variation ecological engineering interaction Beiing–Tianjin Sand source Controlling project(BTSSCP) NDVI
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OSS Project Assessment Based on Discriminant Analysis and Jump Diffusion Process Model for Fault Big Data
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作者 Yoshinobu Tamura Hayato Watanabe Shigeru Yamada 《American Journal of Operations Research》 2020年第6期269-283,共15页
The bug tracking system is well known as the project support tool of open source software. There are many categorical data sets recorded on the bug tracking system. In the past, many reliability assessment methods hav... The bug tracking system is well known as the project support tool of open source software. There are many categorical data sets recorded on the bug tracking system. In the past, many reliability assessment methods have been proposed in the research area of software reliability. Also, there are several software project analyses based on the software effort data such as the earned value management. In particular, the software reliability growth models can </span><span style="font-family:Verdana;">apply to the system testing phase of software development. On the other</span><span style="font-family:Verdana;"> hand, the software effort analysis can apply to all development phase, because the fault data is only recorded on the testing phase. We focus on the big fault data and effort data of open source software. Then, it is difficult to assess by using the typical statistical assessment method, because the data recorded on the bug tracking system is large scale. Also, we discuss the jump diffusion process model based on the estimation method of jump parameters by using the discriminant analysis. Moreover, we analyze actual big fault data to show numerical examples of software effort assessment considering many categorical data set. 展开更多
关键词 Open source Software Big Fault Data Discriminant Analysis Open source project
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Reception pattern influence on magnetoacoustic tomography with magnetic induction 被引量:4
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作者 孙晓冬 王欣 +2 位作者 周雨琦 马青玉 章东 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期329-337,共9页
Based on the acoustic radiation theory of a dipole source, the influence of the transducer reception pattern is studied for magnetoacoustic tomography with magnetic induction(MAT-MI). Numerical studies are conducted... Based on the acoustic radiation theory of a dipole source, the influence of the transducer reception pattern is studied for magnetoacoustic tomography with magnetic induction(MAT-MI). Numerical studies are conducted to simulate acoustic pressures, waveforms, and reconstructed images with unidirectional, omnidirectional, and strong directional transducers.With the analyses of equivalent and projection sources, the influences of the model dimension and the layer effect are qualitatively analyzed to evaluate the performance of MAT-MI. Three-dimensional simulation studies show that the strong directional transducer with a large radius can reduce the influences of equivalent sources, projection sources, and the layer effect effectively, resulting in enhanced pressure and improved image contrast, which is beneficial for boundary pressure extraction in conductivity reconstruction. The reconstructed conductivity contrast images present the conductivity boundaries as stripes with different contrasts and polarities, representing the values and directions of the conductivity changes of the scanned layer. The favorable results provide solid evidence for transducer selection and suggest potential practical applications of MAT-MI in biomedical imaging. 展开更多
关键词 magnetoacoustic tomography with magnetic induction(MAT-MI) reception pattern projection source and equivalent source layer effects
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Design study of APS-U-type hybrid-MBA lattice for mid-energy DLSR 被引量:2
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作者 Yu Zhao Yi Jiao Sheng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第7期46-54,共9页
In recent years,a new generation of storage ring-based light sources,known as diffraction-limited storage rings(DLSRs),whose emittance approaches the diffraction limit for the range of X-ray wavelengths of interest to... In recent years,a new generation of storage ring-based light sources,known as diffraction-limited storage rings(DLSRs),whose emittance approaches the diffraction limit for the range of X-ray wavelengths of interest to the scientific community,has garnered significant attention worldwide.Researchers have begun to design and build DLSRs.Among various DLSR proposals,the hybrid multibend achromat(H-MBA)lattice enables sextupole strengths to be maintained at a reasonable level when minimizing the emittance;hence,it has been adopted in many DLSR designs.Based on the H-7BA lattice,the design of the Advanced Photon Source Upgrade Project(APS-U)can effectively reduce emittance by replacing six quadrupoles with anti-bends.Herein,we discuss the feasibility of designing an APS-U-type H-MBA lattice for the Southern Advanced Photon Source,a mid-energy DLSR light source with ultralow emittance that has been proposed to be built adjacent to the China Spallation Neutron Source.Both linear and nonlinear dynamics are optimized to obtain a detailed design of this type of lattice.The emittance is minimized,while a sufficiently large dynamic aperture(DA)and momentum acceptance(MA)are maintained.A design comprising 36 APS-U type H-7BAs,with an energy of 3 GeV and a circumference of 972 m,is achieved.The horizontal natural emittance is 20 pm·rad,with a horizontal DA of 5.8 mm,a vertical DA of 4.5 mm,and an MA of 4%,as well as a long longitudinal damping time of 120 ms.Subsequently,a few modifications are performed based on the APS-U-type lattice to reduce the maximum value of damping time from 120 to 44 ms while maintaining other performance parameters at the same level. 展开更多
关键词 Southern advanced photon source(SAPS) Diffraction-limited storage ring(DLSR) Hybrid multibend achromat(H-MBA) Advanced photon source upgrade project(APS-U) Lattice design
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Economic Evaluation of a Water Source Project
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作者 WANG Shilin(Institute of Systems Science, Academia Sinica, Beijing, 100080)XUE Yiming(Beijing Business College 100037, China) 《Systems Science and Systems Engineering》 CSCD 1996年第3期361-366,共6页
This paper describes a new method which is different with the shadow price method to evaluate the economic benefits of the water source project. The approach is to take the water source as a constraint on the regiona... This paper describes a new method which is different with the shadow price method to evaluate the economic benefits of the water source project. The approach is to take the water source as a constraint on the regional economic development, calculate the difference between the generaded when the water source project is in operation and the gross product generated when the project is nonexistent, and then review the economic benefits on the project. For this purpose, we have constructed an input-output linear programming model and compiled a compatible using the routines for solving the input-output linear programming model. The above models and the routines have been used in paractical calculation of economic benefits of a water source project for a region. The computation result are satisfactory. 展开更多
关键词 Economic Evaluation of a Water source project source
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OSS Effort Expense Optimization Based on Wiener Process Model and GA
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作者 Kodai Sugisaki Yoshinobu Tamura Shigeru Yamada 《Journal of Software Engineering and Applications》 2021年第1期11-25,共15页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Various open source software are managed by using several bug tracking systems. In particular, the open source softw... <div style="text-align:justify;"> <span style="font-family:Verdana;">Various open source software are managed by using several bug tracking systems. In particular, the open source software extends to the cloud service and edge computing. Recently, OSF Edge Computing Group is launched by OpenStack. There are big data behind the internet services such as cloud and edge computing. Then, it is important to consider the impact of big data in order to assess the reliability of open source software. Various optimal software release problems have been proposed by specific researchers. In the typical optimal software release problems, the cost parameters are defined as the known parameter. However, it is difficult to decide the cost parameter because of the uncertainty. The purpose of our research is to estimate the effort parameters included in our models. In this paper, we propose an estimation method of effort parameter by using the genetic algorithm. Then, we show the estimation method in section 3. Moreover, we analyze actual data to show numerical examples for the estimation method of effort parameter. As the research results, we found that the OSS managers would be able to comprehend the human resources required before the OSS project in advance by using our method.</span> </div> 展开更多
关键词 Fault Big Data Cost Optimization Reliability Analysis Wiener Process Model Open source project
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Outboard abnormal noise source localization method with curved surface projection based on time delay matching and weighting criterion
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作者 YU Wenjing HE Lin +2 位作者 CUI Lilin XU Rongwu LI Ruibiao 《Chinese Journal of Acoustics》 CSCD 2018年第4期448-462,共15页
An improved localization method consisting of "filtering-time delay estimationhyperbolic localization" is proposed. Combining the empirical mode decomposition(EMD)and time delay estimation method based on generali... An improved localization method consisting of "filtering-time delay estimationhyperbolic localization" is proposed. Combining the empirical mode decomposition(EMD)and time delay estimation method based on generalized average magnitude difference function,the original signals are decomposed into intrinsic mode function(IMF) components. The energy distribution criterion and spectrum consistency criterion are used to select the IMFs, which can represent the physical characteristics of the source signal. Several sets of signals are applied to estimate the time delay, and then a vector matching criterion is proposed to select the correct time delay estimation. Considering the hydrophones location, a shell model is established and projected to a plane according to the quadrant before the hyperbolic localization. Results of mooring and sailing tests show that the proposed method improves the localization accuracy,and reduces the error caused by time delay estimation. 展开更多
关键词 Outboard abnormal noise source localization method with curved surface projection based on time delay matching and weighting criterion
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Study on integrated calculation of ecological water demand for basin system 被引量:4
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作者 JIN Xin YAN DengHua +4 位作者 WANG Hao ZHANG Cheng TANG Yun YANG GuiYu WANG LingHe 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第10期2638-2648,共11页
The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecologi... The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s). 展开更多
关键词 ecological operation of reservoir ecological water demand integrated calculation distributed hydrological model west route of South-North Water Transfer project in Yalong River source area
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