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Financial Calculation Problems and Countermeasure Analysis of Large-Scale Engineering Construction Projects
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作者 Qiong Hou 《Proceedings of Business and Economic Studies》 2024年第2期15-21,共7页
The financial aspects of large-scale engineering construction projects profoundly influence their success.Strengthening cost control and establishing a scientific financial evaluation system can enhance the project’s... The financial aspects of large-scale engineering construction projects profoundly influence their success.Strengthening cost control and establishing a scientific financial evaluation system can enhance the project’s economic benefits,minimize unnecessary costs,and provide decision-makers with a robust financial foundation.Additionally,implementing an effective cash flow control mechanism and conducting a comprehensive assessment of potential project risks can ensure financial stability and mitigate the risk of fund shortages.Developing a practical and feasible fundraising plan,along with stringent fund management practices,can prevent fund wastage and optimize fund utilization efficiency.These measures not only facilitate smooth project progression and improve project management efficiency but also enhance the project’s economic and social outcomes. 展开更多
关键词 large-scale engineering construction projects Financial calculation Fund management
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Modular Extremely Large-Scale Array Communication:Near-Field Modelling and Performance Analysis 被引量:2
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作者 Xinrui Li Haiquan Lu +2 位作者 Yong Zeng Shi Jin Rui Zhang 《China Communications》 SCIE CSCD 2023年第4期132-152,共21页
This paper investigates the wireless communication with a novel architecture of antenna arrays,termed modular extremely large-scale array(XLarray),where array elements of an extremely large number/size are regularly m... This paper investigates the wireless communication with a novel architecture of antenna arrays,termed modular extremely large-scale array(XLarray),where array elements of an extremely large number/size are regularly mounted on a shared platform with both horizontally and vertically interlaced modules.Each module consists of a moderate/flexible number of array elements with the inter-element distance typically in the order of the signal wavelength,while different modules are separated by the relatively large inter-module distance for convenience of practical deployment.By accurately modelling the signal amplitudes and phases,as well as projected apertures across all modular elements,we analyse the near-field signal-to-noise ratio(SNR)performance for modular XL-array communications.Based on the non-uniform spherical wave(NUSW)modelling,the closed-form SNR expression is derived in terms of key system parameters,such as the overall modular array size,distances of adjacent modules along all dimensions,and the user's three-dimensional(3D)location.In addition,with the number of modules in different dimensions increasing infinitely,the asymptotic SNR scaling laws are revealed.Furthermore,we show that our proposed near-field modelling and performance analysis include the results for existing array architectures/modelling as special cases,e.g.,the collocated XL-array architecture,the uniform plane wave(UPW)based far-field modelling,and the modular extremely large-scale uniform linear array(XL-ULA)of onedimension.Extensive simulation results are presented to validate our findings. 展开更多
关键词 modular extremely large-scale array practical deployment projected apertures non-uniform spherical wave near-field modelling
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The Jiao Tong University Spectroscopic Telescope Project 被引量:1
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作者 JUST Team Chengze Liu +28 位作者 Ying Zu Fabo Feng Zhaoyu Li Yu Yu Hua Bai Xiangqun Cui Bozhong Gu Yizhou Gu Jiaxin Han Yonghui Hou Zhongwen Hu Hangxin Ji Yipeng Jing Wei Li Zhaoxiang Qi Xianyu Tan Cairang Tian Dehua Yang Xiangyan Yuan Chao Zhai Congcong Zhang Jun Zhang Haotong Zhang Pengjie Zhang Yong Zhang Yi Zhao Xianzhong Zheng Qingfeng Zhu Xiaohu Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期16-30,共15页
The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a di... The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 m.JUST provides two Nasmyth platforms for placing science instruments.One Nasmyth focus fits a field of view of 10′and the other has an extended field of view of 1.2°with correction optics.A tertiary mirror is used to switch between the two Nasmyth foci.JUST will be installed at a site at Lenghu in Qinghai Province,China,and will conduct spectroscopic observations with three types of instruments to explore the dark universe,trace the dynamic universe,and search for exoplanets:(1)a multi-fiber(2000 fibers)medium-resolution spectrometer(R=4000-5000)to spectroscopically map galaxies and large-scale structure;(2)an integral field unit(IFU)array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy;(3)a high-resolution spectrometer(R~100000)designed to identify Jupiter analogs and Earth-like planets,with the capability to characterize the atmospheres of hot exoplanets. 展开更多
关键词 Astronomical instrumentation Optical telescopes large-scale structure of the universe Redshift surveys Time domain astronomy Exoplanet astronomy
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Design of High Precision Horizontal Control Network for Large-Scale Hydropower Project
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作者 ZHANG Zhenglu LUO Changlin +1 位作者 DENG Yong XIE Niansheng 《Geo-Spatial Information Science》 2006年第4期235-239,共5页
A new solution of combination network of GPS and high precise distance measurements with EDM is proposed. Meanwhile, it’s inadvisable only using GPS network without distance measurements. Three schemes: terrestrial n... A new solution of combination network of GPS and high precise distance measurements with EDM is proposed. Meanwhile, it’s inadvisable only using GPS network without distance measurements. Three schemes: terrestrial network, GPS network and combination network are discussed for horizontal control network design of Xiangjiaba Dam in view of precision, reliability, coordinate and outlay in detail. 展开更多
关键词 large-scale hydropower project terrestrial network GPS network combination network of GPS and high precise distance measurements with EDM
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A Large-Scale Survey for Extremely Cold Young Stellar Objects in the Galaxy
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作者 Yang Ji 1,2 ,Jiang Zhibo 1,2 ,Wang Min 1,2 ,Wang Hongchi 1,2 ,Hiroshi Kimura 1,3 1(Purple Mountain Observatory, The Chinese Academy of Sciences, Nanjing 210008, China) 2(National Astronomical Observatories, The Chinese Academy of 《天文研究与技术》 CSCD 1999年第S1期166-174,共9页
We conducted a large-scale survey of the extremely-cold infrared sources(ECISs) along the Galactic plane. There are 1912 (IRAS) sources selected on the basis of their color indices and their association with recent st... We conducted a large-scale survey of the extremely-cold infrared sources(ECISs) along the Galactic plane. There are 1912 (IRAS) sources selected on the basis of their color indices and their association with recent star formation. A quick survey was made toward 724 sources. There are 251 sources detected with significant CO emission during the quick survey above the detection limit of 0 9 K. Among the various sources detected, there are 147 sources found to have broad CO wing emission, including 116 newly detected sources. These sources comprise a new database for future study of star formation in our Galaxy. Using the known outflow sources as an effective indicator, we found the outflow detection rate of the quick survey is 62%, reasonably sensitive in survey for new outflow sources. Results from limited follow-up studies are introduced. 展开更多
关键词 Stellar Objects in the Galaxy A large-scale survey for Extremely Cold Young
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Comparison of life cycle assessment of large-scale biogas projects with different raw materials in China
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作者 Jiazheng Sun Youpei Qu +4 位作者 Xiaoyi Lyu Xinjie Ding Xinying Miao Mukesh Kumar Awasthi Jingbo Qu 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第2期268-279,共12页
The anaerobic digestion(AD)disposal of stover and cattle manure is of great significance to the development of low-carbon economy and green energy in China,but it will also have an impact on the environment,and the de... The anaerobic digestion(AD)disposal of stover and cattle manure is of great significance to the development of low-carbon economy and green energy in China,but it will also have an impact on the environment,and the degree of influence is different for various raw materials.In this study,life cycle assessment(LCA)methods were applied to analyze and compare the impact of corn stovers biogas projects(CSBP)and dairy manure biogas projects(DMBP)on the environment during the whole operation stage.The results of inventory analysis were evaluated by ReCiPe2016 Hierarchy(H)mid-point(problem-oriented)and end-point(destruction-oriented)method,respectively.The results showed that the net energy efficiency of CSBP was higher(763.903 kW·h/FU)and the greenhouse gas(GHG)emission reduction of DMBP was more(5541.418 kg CO_(2)-eq/FU).The anaerobic digestion(AD)units have the greatest environmental impacts,and human carcinogenic toxicity is the largest environmental impact category(1.16-1.43 PE).The key to reducing environmental impact is reducing the input of chemical substances and the waste of electric energy.Both CSBP and DMBP have a favorable impact on ecosystem quality and resources,and CSBP is more beneficial to the environment(-10.297 Pt).Co-digestion is an important measure to reduce the environmental damage from biogas projects.These research results provide theoretical support for the selection of raw materials for large-scale biogas projects in China,provide technical basis for reducing the impact of actual operation on the environment,and promote the resource utilization of agricultural waste and carbon dioxide emission reduction and sequestration. 展开更多
关键词 life cycle assessment environmental impact assessment large-scale biogas projects BIOENERGY carbon dioxide emission reduction
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Inaccuracy of Self-reported Low Sodium Diet among Chinese: Findings from Baseline Survey for Shandong & Ministry of Health Action on Salt and Hypertension(SMASH) Project 被引量:2
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作者 ZHANG Juan GUO Xiao Lei +13 位作者 Dong Chul SEO XU Ai Qiang XUN Peng Cheng MA Ji Xiang SHI Xiao Ming Nicole LI YAN Liu Xia LI Yuan LU Zi Long ZHANG Ji Yu TANG Jun Li REN Jie ZHAO Wen Hua LIANG Xiao Feng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第2期161-167,共7页
This study was aimed to evaluate the agreement between the self-reported sodium intake level and 24-h urine sodium excretion level in Chinese. The 24-h urine collection was conducted among 2112 adults aged 18-69 years... This study was aimed to evaluate the agreement between the self-reported sodium intake level and 24-h urine sodium excretion level in Chinese. The 24-h urine collection was conducted among 2112 adults aged 18-69 years randomly selected in Shandong Province, China. The subjects were asked whether their sodium intake was low, moderate, or high. The weighted kappa statistics was calculated to assess the agreement between 24-h urine sodium excretion level and self-reported sodium intake level. One third of the subjects reported low sodium intake level. About 70% of the subjects had mean 24-h sodium excretion 〉9 g/d, but reported low or moderate sodium intake. 展开更多
关键词 Ministry of Health Action on Salt and Hypertension Findings from Baseline survey for Shandong SMASH project
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Summary Report of the Sample Survey on School Attendance in Project Counties of Guizhou
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《China Population Today》 1994年第2期14-17,1,共5页
In ordcr to asscss the school attendance status of children aged 7-14 to determine the causes of non-at-tendance,and to formulate appropriate policics for the implementation of the ninc-ycar compulsory cduca-tion prog... In ordcr to asscss the school attendance status of children aged 7-14 to determine the causes of non-at-tendance,and to formulate appropriate policics for the implementation of the ninc-ycar compulsory cduca-tion programme,a sample survcy on school--agc:children was carried out in Jianhc,Lcishan and Taijang,Guizhou Province in October 1993. 展开更多
关键词 GUIZHOU Counties ATTENDANCE project REPORT SAMPLE SCHOOL SUMMARY survey in
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On the Large-Scale Structure of the Universe as given by the Voronoi Diagrams
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作者 L. Zaninetti 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第4期387-395,共9页
The size distributions of 2D and 3D Voronoi cells and of cells of Vp(2, 3),--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter (re-scaled) gamma distribution playing a central role in the analy... The size distributions of 2D and 3D Voronoi cells and of cells of Vp(2, 3),--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter (re-scaled) gamma distribution playing a central role in the analytical fitting. Observational evidence for a cellular universe is briefly reviewed. A simulated Vp(2, 3) map with galaxies lying on the cell boundaries is constructed to compare, as regards general appearance, with the observed CfA map of galaxies and voids, the parameters of the simulation being so chosen as to reproduce the largest observed void size. 展开更多
关键词 surveys -- galaxies CLUSTERS general -- (cosmology:) large-scale structure of Universe
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A Survey of the Xia-Shang-Zhou Chronology Project
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作者 Xi Zezong(Institute for the History of Natural Science, CAS) 《Bulletin of the Chinese Academy of Sciences》 2002年第1期34-41,共8页
Ⅰ. Goals In connection with the history of science, the XiaShang-Zhou Chronology Project is one of the important projects of the National Key Science and Technology Research and Development Programme of the Ninth Fiv... Ⅰ. Goals In connection with the history of science, the XiaShang-Zhou Chronology Project is one of the important projects of the National Key Science and Technology Research and Development Programme of the Ninth Five-Year Plan. It officially began in May 1996.After five years of effort by more than 200 scholars and experts from the Chinese Academy of Sciences,the Chinese Academy of Social Sciences, Peking University and other institutions, the project has attained its goal. The general goal of the project is to establish a chronological table for the three dynasties by means of combining the humanities and social sciences with the natural sciences. The concrete goals for different historical periods are: 展开更多
关键词 King BC A survey of the Xia-Shang-Zhou Chronology project
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering
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Survey and technological analysis of laser and its defense applications 被引量:13
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作者 Syed Affan Ahmed Mujahid Mohsin Syed Muhammad Zubair Ali 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期583-592,共10页
The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electron... The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military weapons.Owing to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive roles.In modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground targets.Additionally,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial applications.Moreover,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical operations.Furthermore,the developments in space sciences and laser technology have given synergistic potential outcomes to use laser systems in space operations.This paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in space.Additionally,a detailed analysis has been done on recent advancements of the laser technology for target indicators and range-finders.It also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and advancements in the domain of high energy directed laser weapons that have revolutionized the evolving military battlefield.Besides offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains. 展开更多
关键词 Laser systems Laser military applications Directed energy weapons Non-lethal weapons Laser military projects survey TAXONOMY
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Main progress and prospect for China’s hydrogeological survey 被引量:6
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作者 WU Ai-min HAO Ai-bing +6 位作者 GUO Hai-peng LIU Jing-tao ZHANG Er-yong WANG Huang WANG Xin-feng WEN Xue-ru ZHANG Cui-guang 《Journal of Groundwater Science and Engineering》 2020年第3期195-209,共15页
This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeologic... This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeological survey in the“14th Five-year Plan”.The significant progress includes:China established the 1:50000 standard hydrogeological survey system with Chinese characteristics and produced the new generation of highquality hydrogeological maps;the national groundwater monitoring project was completed and accepted,which marks China taking the leading position in groundwater monitoring internationally;fruitful results were achieved in the national groundwater quality survey,and groundwater quality background values were basically identified and checked;hydrogeological and environmental geological survey was continuously promoted in karst areas and the ecological restoration of rocky desertification achieved remarkable results;China strengthened layer exploration techniques for groundwater,integrating the key and practical techniques of layer exploration and monitoring;the exploration of groundwater in the poverty-stricken regions and old revolutionary base areas were effectively promoted to strongly guarantee the poverty alleviation and drinking water safety;the mystery of desert groundwater was uncovered,making up for the shortage of 1:250000 hydrogeological survey in the Badain Jaran Desert;and more efforts were made to conduct survey on the water resources in the basin,and to finish the unified measurement of national-scale groundwater level. 展开更多
关键词 Hydrogeological survey National Groundwater Monitoring project Groundwater quality background values Ecological restoration of rocky desertification China
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Practice and experience of engineering culture development in the Sutong Bridge project
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作者 Yu Chunsheng Yao Bei Wang Qian 《Engineering Sciences》 EI 2009年第1期87-92,共6页
To keep up with the time,culture is integrated to large-scale construction project management in China,which will absolutely add more vitality into construction project management in our country.Engineering culture is... To keep up with the time,culture is integrated to large-scale construction project management in China,which will absolutely add more vitality into construction project management in our country.Engineering culture is an integration of project construction and engineering culture.However,engineering culture development enjoys its own particularity as a project is constructed once only within a limited period of time.This paper gives affirmative opinion that engineering culture development in large-scale projects backs project management on the basis of thorough investigation of engineering culture development in Sutong Bridge Project and after deepened analysis,proposes new thinking pattern of engineering culture development in large-scale projects in a systematic manner,including thorough understanding of the essence of engineering culture,principle and contents of engineering culture development as well as efficient method in respect of establishment and implementation of engineering culture,and therefore provides a standard reference and systematic thinking pattern for engineering culture development in future large-scale projects. 展开更多
关键词 large-scale projects engineering culture engineering culture development systematic thinking pattern
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Monotone projected gradient methods for large-scale box-constrained quadratic programming 被引量:3
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作者 ZHOU Bin, GAO Li & DAI Yuhong School of Mathematical Sciences and LMAM, Peking University, Beijing 100871, China State Key Laboratory of Scientific and Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China 《Science China Mathematics》 SCIE 2006年第5期688-702,共15页
Inspired by the success of the projected Barzilai-Borwein (PBB) method for largescale box-constrained quadratic programming, we propose and analyze the monotone projected gradient methods in this paper. We show by exp... Inspired by the success of the projected Barzilai-Borwein (PBB) method for largescale box-constrained quadratic programming, we propose and analyze the monotone projected gradient methods in this paper. We show by experiments and analyses that for the new methods,it is generally a bad option to compute steplengths based on the negative gradients. Thus in our algorithms, some continuous or discontinuous projected gradients are used instead to compute the steplengths. Numerical experiments on a wide variety of test problems are presented, indicating that the new methods usually outperform the PBB method. 展开更多
关键词 projected gradients MONOTONE GRADIENT methods box-constrained QUADRATIC programming large-scale problems.
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Variations in tidal currents and suspended sediment concentration of the upper part of the North Channel of Changjiang Estuary over the past 10 years 被引量:1
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作者 刘高伟 程和琴 +3 位作者 计娜 乔远英 胡浩 王冬梅 《Marine Science Bulletin》 CAS 2015年第2期9-24,共16页
The tidal current duration (TCD) and velocity (TCV) and suspended sediment concentration (SSC) were measured in the dry season in December, 2011 and in the flood season in June, 2012 at the upper part of the Nor... The tidal current duration (TCD) and velocity (TCV) and suspended sediment concentration (SSC) were measured in the dry season in December, 2011 and in the flood season in June, 2012 at the upper part of the North Channel of Changjiang Estuary. They were assimilated with the measured data in 2003, 2004, 2006 and 2007, using the tidal range's proportion conversion. Variations in TCD and TCV, preferential flow and SSC have been calculated. Influences of typical engineering projects such as Qingcaosha fresh water reservoir, Yangtze River Bridge, and land reclamation on the ebb and flood TCD, TCV and SSC in the North Channel for the last 10 years are discussed. The results show that: (1) currently, in the upper part of North Channel, the ebb tide dominates; after the construction of the typical projects, ebb TCD and TCV tends to be larger and the vertical average ebb and flood SSC decrease during the flood season while SSC increases during the dry season; (2) changes in the vertical average TCV are mainly contributed by seasonal runoff variation during the flood season, which is larger in the flood season than that in the dry season; the controlling parameters of increasing ebb TCD and TCV are those large-scale engineering projects in the North Channel; variation in SSC may result mainly from the reduction of basin annual sediment loads, large-scale nearshore projects and so on. 展开更多
关键词 changes in tidal currents and suspended sediment concentration preferential flow data assimilation large-scale engineering projects Changjiang Estuary
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The hydrochemical characteristics and its significance of geothermal water in both sides of large fault: Taking northern section of the Liaokao fault in north China as an example 被引量:5
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作者 Bao-jian Zhang Tian Zhao +6 位作者 Yan-yan Li Yi-fei Xing Gui-ling Wang Jun Gao Xian-chun Tang Wen-zhen Yuan Dai-lei Zhang 《China Geology》 2019年第4期512-521,共10页
Based on comparative analysis on hydrochemical characteristics of geothermal water in the north part of Liaokao fault,this research focuses on studying the indicative significance of hydrochemical characteristics for ... Based on comparative analysis on hydrochemical characteristics of geothermal water in the north part of Liaokao fault,this research focuses on studying the indicative significance of hydrochemical characteristics for the formation of geothermal water.The result shows that:(1)There is no obvious hydraulic connection between the karst geothermal water(occurred in the east part of the Liaokao fault)and the sandstone geothermal water(occurred in the west part of Liaokao fault).(2)In a close hydrological environment,caused by tectonic activities,geothermal water remains longer time in reservoir,hence the water-rock interaction is more complete,with high degree of concentrations,whereas the renewable capacity of the water is weaker.(3)There is no high temperature mantle source fluid mixed in the geothermal water.Karst geothermal water occurred deep circulatory convection along Liaokao fault and its secondary fault,therefore there is deep crust source fluid added into the geothermal water,closer to the Liaokao fault,the greater affected by the deep crust fluid.However,sandstone geothermal water has weak deep circulatory convection. 展开更多
关键词 GEOTHERMAL survey engineering large-scale FAULT HYDROCHEMISTRY GEOTHERMAL water ZONAL characteristics Indicative MEANING Liaokao FAULT North China
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Economical Requirements Elicitation Techniques During COVID-19: A Systematic Literature Review
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作者 Tauqeer ul Amin Basit Shahzad +1 位作者 Fazal-e-Amin Muhammad Shoaib 《Computers, Materials & Continua》 SCIE EI 2021年第5期2665-2680,共16页
Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and... Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and a project may fail if there are excessive costs and schedule overruns.COVID-19 has affected the software industry by reducing interactions between developers and customers.Such a lack of interaction is a key reason for the failure of software projects.Projects can also fail when customers do not know precisely what they want.Furthermore,selecting the unsuitable elicitation technique can also cause project failure.The present study,therefore,aimed to identify which requirements elicitation technique is the most cost-effective for large-scale projects when time to market is a critical issue or when the customer is not available.To that end,we conducted a systematic literature review on requirements elicitation techniques.Most primary studies identified introspection as the best technique,followed by survey and brainstorming.This finding suggests that introspection should be the first choice of elicitation technique,especially when the customer is not available or the project has strict time and cost constraints.Moreover,introspection should also be used as the starting point in the elicitation process of a large-scale project,and all known requirements should be elicited using this technique. 展开更多
关键词 COVID-19 software engineering requirements engineering requirements elicitation INTROSPECTION project failure SLR on elicitation techniques large-scale projects economical elicitation techniques costeffective time constraints
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Forecasts of cosmological constraints from HI intensity mapping with FAST,BINGO and SKA-I
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作者 Elimboto Yohana Yi-Chao Li Yin-Zhe Ma 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第12期343-360,共18页
We forecast the cosmological constraints of the neutral hydrogen(HI) intensity mapping(IM)technique with radio telescopes by assuming 1-year of observational time. The current and future radio telescopes that we consi... We forecast the cosmological constraints of the neutral hydrogen(HI) intensity mapping(IM)technique with radio telescopes by assuming 1-year of observational time. The current and future radio telescopes that we consider here are Five-hundred-meter Aperture Spherical radio Telescope(FAST), Baryon acoustic oscillations In Neutral Gas Observations(BINGO), and Square Kilometre Array phase Ⅰ(SKA-Ⅰ) single-dish experiments. We also forecast the combined constraints of the three radio telescopes with Planck. We find that the 1σ errors of(w0, wa) for BINGO, FAST and SKA-Ⅰ with respect to the fiducial values are respectively,(0.9293, 3.5792),(0.4083, 1.5878) and(0.3158, 0.4622). This is equivalent to(56.04%, 55.64%) and(66.02%, 87.09%) improvements in constraining(w0, wa) for FAST and SKA-Ⅰ respectively relative to BINGO. Simulations further show that SKA-Ⅰ will put more stringent constraints than both FAST and BINGO when each of the experiments is combined with Planck measurements. The 1σ errors for(w0, wa), BINGO + Planck, FAST + Planck and SKA-Ⅰ + Planck covariance matrices are respectively(0.0832, 0.3520),(0.0791, 0.3313) and(0.0678, 0.2679) implying there is an improvement in(w0, wa) constraints of(4.93%, 5.88%) for FAST + Planck relative to BINGO + Planck and an improvement of(18.51%, 23.89%) in constraining(w0, wa) for SKA-Ⅰ + Planck relative to BINGO + Planck. We also compared the performance of Planck data plus each single-dish experiment relative to Planck alone,and find that the reduction in(w0, wa) 1σ errors for each experiment plus Planck, respectively, imply the(w0, wa) constraints improvement of(22.96%, 8.45%),(26.76%, 13.84%) and(37.22%, 30.33%) for BINGO + Planck, FAST + Planck and SKA-Ⅰ + Planck relative to Planck alone. For the nine cosmological parameters in consideration, we find that there is a trade-off between SKA-Ⅰ and FAST in constraining cosmological parameters, with each experiment being more superior in constraining a particular set of parameters. 展开更多
关键词 surveys galaxies:statistics cosmology:observations large-scale structure of Universe galaxies:kinematics and dynamics
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Strategic Height of Standards Arena
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作者 李春田 《China Standardization》 2015年第3期68-77,共10页
The article explains the meaning and its extreme importance of the strategic heights for the standardization field, deliberates over the challenges for traditional standardization, and proposes the urgency of the tran... The article explains the meaning and its extreme importance of the strategic heights for the standardization field, deliberates over the challenges for traditional standardization, and proposes the urgency of the transformation towards modernized standardization. Affirming the limited role of existing methods like modularization and comprehensive standardization, the author insists on the necessity of accelerating the development of modernized standardization to meet the increasing demand of modern society towards standardization. It is a historical mission for current standardizers to focus on theories, methodologies and innovations in the modern standardization arena. 展开更多
关键词 STANDARDIZATION large-scale project complex product system MODULARIZATION comprehensivestandardization modern standardization
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