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Knowledge graph construction and complementation for research projects
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作者 LI Tongxin LIN Mu +2 位作者 WANG Weiping LI Xiaobo WANG Tao 《Journal of Systems Engineering and Electronics》 2025年第3期725-735,共11页
Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often comple... Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often complex and inadequate,making it challenging for researchers to conduct in-depth data mining to improve policies or management.To address this problem,this paper adopts a top-down approach to construct a knowledge graph(KG)for research projects.Firstly,we construct an integrated ontology by referring to the metamodel of various architectures,which is called the meta-model integration conceptual reference model.Subsequently,we use the dependency parsing method to extract knowledge from unstructured textual data and use the entity alignment method based on weakly supervised learning to classify the extracted entities,completing the construction of the KG for the research projects.In addition,a knowledge inference model based on representation learning is employed to achieve knowledge completion and improve the KG.Finally,experiments are conducted on the KG for research projects and the results demonstrate the effectiveness of the proposed method in enriching incomplete data within the KG. 展开更多
关键词 research projects knowledge graph(KG) KG completion
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Ranking environmental projects model based on multicriteria decision-making and the weight sensitivity analysis 被引量:5
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作者 Jiang Yan Tian Dagang Pan Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期534-539,共6页
With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental qua... With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports' information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals (WSI), the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them. 展开更多
关键词 multicriteria decision-making ranking environmental projects model PROMETHEE method sensitivity analysis weight stability intervals.
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Minimal feasible sets in variable resource constrained projects
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作者 Cui Wanan~(1,2,3),Yue Chaoyuan~3,Chen Yingchun~4 & Cao Xiuning~5 1.Coll.of Management,Guangxi Univ.for Nationalities,Nanning 530006,P.R.China 2.School of Economics and Management,Wuhan Univ.,Wuhan 430072,P.R.China +2 位作者 3.Inst.of Systems Engineering,Huazhong Univ.of Science and Technology,Wuhan 430074,P.R.China 4.Unit 91388 of the PLA,Zhanjiang 524022,P.R.China 5.School of Business,Hunan Univ.of Science and Technology,Xiangtan 411201,P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期974-984,共11页
To determine the reasonable resource dependent relations between activities for the purpose of exactly computing the total floats and the free floats of activities, correctly identifying critical activities and critic... To determine the reasonable resource dependent relations between activities for the purpose of exactly computing the total floats and the free floats of activities, correctly identifying critical activities and critical sequences in a project schedule with variable resource constraints, the concept of the minimal feasible set (MFS) is proposed and the properties of MFS are discussed. The methods to identify optimal MFSs and resource links are then studied. Furthermore, MFS is generalized to the situation that the preconditions of MFS are not satisfied. Contrastive results show that in establishing resource links and resolving floats, MFS is at least not inferior to other methods in all cases and is superior in most situations. 展开更多
关键词 project schedule resource constraint minimal feasible set resource dependent relation.
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IMPACTS OF THE SOUTH-TO-NORTH WATER DIVERSION PROJECTS (MIDDLE ROUTE)ON THE WATER ENVIRONMENT OF THE MIDDLE AND LOWER REACHES OF THE HANJIANG RIVER
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作者 FAN Bei-Lin, WAN Jian-Rong, ZHANG Jie and LIN Qiu-Sheng (Yangtze River Scientific Research Institute,River Research Deparment, Wuhan 430010,China) 《水生生物学报》 CAS CSCD 北大核心 2006年第6期643-646,共4页
In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well... In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well as their impacts on the environment of the middle and lower reaches of the Hanjiang River. The results showed that the 95×10 8m 3 water diversion scheme will cause less erosion and water level decrease than the 15×10 8m 3 water diversion scheme. Using a water diversion scheme of 95×10 8m 3, the decrease of water quantity can impact the river hydrodynamic regime substantially and the environments of the middle and lower reaches of the Hanjiang River will be greatly affected. It is therefore necessary to develop new water resources or build projects to meet the need of the environment and the needs for navigation. 展开更多
关键词 South-to-North Water Diversion Project River regime Water environment Mathematical model
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JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING NOTES FOR CONTRIBUTORS
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《深圳大学学报(理工版)》 北大核心 2025年第4期F0003-F0003,共1页
Aim Journal of Shenzhen University Science and Engineering,a bimonthly journal with its first issuing in 1984,is now administered and sponsored by Shenzhen University and published by the Science Press.It is a peer-re... Aim Journal of Shenzhen University Science and Engineering,a bimonthly journal with its first issuing in 1984,is now administered and sponsored by Shenzhen University and published by the Science Press.It is a peer-reviewed journal that publishes original papers of high scientific value.Innovation is always the starting point for the progress of our journal.We pay more attention to funded projects and major topics during manuscript organization to present the latest scientific and engineering achievements in China,as well as innovations in Shenzhen and Shenzhen University. 展开更多
关键词 scientific value original papers manuscript organization funded projects peer reviewed journal major topics innovation
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Color projector light intensity adaptive high dynamic range 3D measurement method
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作者 HUANG Hao-zhen NIU Bin +2 位作者 CHENG Shen QU Xing-hua ZHANG Fu-min 《中国光学(中英文)》 北大核心 2025年第5期1219-1229,共11页
The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,re... The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,resulting in point cloud loss or reduced accuracy.To address this issue,unlike the pixel modulation method of projectors,we utilize the characteristics of color projectors where the intensity of the three-channel LED can be controlled independently.We propose a method for separating the projector's three-channel light intensity,combined with a color camera,to achieve single exposure and multi-intensity image acquisition.Further,the crosstalk coefficient is applied to predict the three-channel reflectance of the measured object.By integrating clustering and channel mapping,we establish a pixel-level mapping model between the projector's three-channel current and the camera's three-channel image intensity,which realizes the optimal projection current prediction and the high dynamic range(HDR)image acquisition.The proposed method allows for high-precision three-dimensional(3D)data acquisition of HDR scenes with a single exposure.The effectiveness of this method has been validated through experiments with standard planes and standard steps,showing a significant reduction in mean absolute error(44.6%)compared to existing singleexposure HDR methods.Additionally,the number of images required for acquisition is significantly reduced(by 70.8%)compared to multi-exposure fusion methods.This proposed method has great potential in various FPP-related fields. 展开更多
关键词 fringe projection profilometry crosstalk coefficient optimal projection currents high dynamic range
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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Current status and diversity of fish resources in the Pinglu Canal Century Project
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal Project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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微项目化学习在人教版初中英语新教材中的实施路径——以Project板块为例
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作者 吕勇民 《中小学英语教学与研究》 北大核心 2025年第1期72-76,共5页
2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习... 2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习的实施路径,即学生在真实情境中发现问题,通过小组合作分解问题,在探索实践中解决问题,接着相互交流分享心得并评价作品,进而对作品升级迭代,再自评参与表现,最终实现素养发展。希望能以此促进课堂教学方式转变,提升教学效能。 展开更多
关键词 初中英语 新教材 PROJECT板块 微项目化学习
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Progress of Taiji-2 Project 被引量:1
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作者 LUO Ziren ZHANG Min +1 位作者 WANG Jianyu WU Yueliang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期674-676,共3页
Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced ... Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced here. 展开更多
关键词 Gravitational wave Taiji program Taiji-2 project
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Novel method for extraction of ship target with overlaps in SAR image via EM algorithm 被引量:1
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作者 CAO Rui WANG Yong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期874-887,共14页
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition... The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method. 展开更多
关键词 expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)
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Construction and Research Progress of the Chinese Meridian Project in 2022–2023
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作者 WANG Chi CHEN Zhiqing XU Jiyao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期704-711,共8页
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing... The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research. 展开更多
关键词 Chinese Meridian Project(CMP) MAGNETOSPHERE IONOSPHERE Middle and upper atmosphere
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A process monitoring method for autoregressive-dynamic inner total latent structure projection
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作者 CHEN Yalin KONG Xiangyu LUO Jiayu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1326-1336,共11页
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos... As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system. 展开更多
关键词 dynamic characteristic fault detection feature extraction process monitoring projection to latent structure(PLS) quality-related spatial partitioning
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货币政策、企业异质性与债务期限结构
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作者 雷国胜 杨阳 《管理现代化》 北大核心 2024年第4期59-69,共11页
基于2007-2022年A股上市公司季度数据,考察货币政策冲击对企业债务期限结构的影响。研究结果表明:在紧缩性货币政策冲击的影响下,企业债务期限结构受到显著的负面影响,但是这种影响不是瞬时的,而是在冲击发生后的第一个季度才显示出来,... 基于2007-2022年A股上市公司季度数据,考察货币政策冲击对企业债务期限结构的影响。研究结果表明:在紧缩性货币政策冲击的影响下,企业债务期限结构受到显著的负面影响,但是这种影响不是瞬时的,而是在冲击发生后的第一个季度才显示出来,并且随时间的推移其下降趋势先增后减,整体呈现“U”型;从融资约束视角来看,融资约束越大的企业其债务期限结构在货币政策冲击发生时受到影响更大,且受影响时间更长;从行业视角来看,相较于技术密集型行业,资本密集型和劳动密集型行业更为敏感,对货币政策冲击对债务期限结构的影响更加显著。研究结果丰富了货币政策对债务期限结构影响的研究,并为相关政策的制定提供了有益参考。 展开更多
关键词 货币政策 债务期限结构 融资约束 Proxy-SVAR Local Projection
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Ship recognition based on HRRP via multi-scale sparse preserving method
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作者 YANG Xueling ZHANG Gong SONG Hu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期599-608,共10页
In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) ba... In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance. 展开更多
关键词 ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction
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Progress of International Meridian Circle Program
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作者 WANG Chi BLANC Michel +13 位作者 ZHANG Shunrong DENARDINI Clezio Marcos LIU William SHEN Xuhui WU Jian XU Jiyao LI Hui ZHANG Qinghe REN Liwen ZHU Yajun LI Guozhu DING Zonghua LIU Zhengkuan YANG Fang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期741-745,共5页
In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the I... In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil. 展开更多
关键词 Chinese Meridian Project(CMP) International Meridian Circle Program(IMCP) China-Brazil Joint Laboratory for Space Weather North Pole and Southeast Asia networks
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WEPP细沟剥蚀率模型正确性的理论分析与实验验证 被引量:17
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作者 张晴雯 雷廷武 +2 位作者 姚春梅 潘英华 王辉 《农业工程学报》 EI CAS CSCD 北大核心 2004年第1期35-39,共5页
基于物理过程基础上的WEPP土壤水蚀预报模型将坡面侵蚀分为细沟侵蚀和细沟间侵蚀,建立了独立的细沟间模型和细沟模型。其中细沟侵蚀产沙方程从概念上可以预报细沟侵蚀过程,但没经实验或理论验证。该文经过理论分析表明,WEPP模型中的剥... 基于物理过程基础上的WEPP土壤水蚀预报模型将坡面侵蚀分为细沟侵蚀和细沟间侵蚀,建立了独立的细沟间模型和细沟模型。其中细沟侵蚀产沙方程从概念上可以预报细沟侵蚀过程,但没经实验或理论验证。该文经过理论分析表明,WEPP模型中的剥蚀率是水流含沙量的线性函数,并由给定的试验条件计算得到了函数中的参数。将理论分析结果和已有的实验结果进行了比较,验证了WEPP中的侵蚀产沙模型。同时将已得到的确定细沟剥蚀率的微分方程代入细沟侵蚀产沙方程并求解,从理论上得到了含沙量随沟长变化的函数关系。将理论分析结果和由实验所得的结果进行了对比,进一步验证了WEPP中的侵蚀产沙模型。该文从细沟剥蚀率和产沙量两方面对WEPP模型中细沟侵蚀产沙模型进行了验证。 展开更多
关键词 WEPP(Water EROSION PREDICTION Project) 细沟侵蚀 剥蚀率 模型验证
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OPLS方法的原理及其在代谢组学数据判别分析中的应用 被引量:16
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作者 李俊南 侯艳 +1 位作者 孙凤宇 李康 《中国卫生统计》 CSCD 北大核心 2014年第5期765-769,共5页
目的探讨orthogonal projection to latent structures(OPLS)方法的原理、特点及其在代谢组学高维数据分析中的应用。方法通过R语言编程实现OPLS方法,利用模拟试验探索OPLS的特性及适用条件,并通过实际数据进行验证。结果利用一个OPLS... 目的探讨orthogonal projection to latent structures(OPLS)方法的原理、特点及其在代谢组学高维数据分析中的应用。方法通过R语言编程实现OPLS方法,利用模拟试验探索OPLS的特性及适用条件,并通过实际数据进行验证。结果利用一个OPLS预测主成分的模型拟合效果与利用偏最小二乘(PLS)多个主成分的模型拟合效果相同,同时具有较好的判别能力,其得分图的可视化效果优于PLS。结论 OPLS能够有效去除自变量矩阵X中与因变量Y无关的信息,使模型变得简单、易于解释,同时具有较好的可视化效果,可有效地用于代谢组学数据分析中。 展开更多
关键词 ORTHOGONAL PROJECTION to LATENT structures(OPLS) 模型拟合 可视化 代谢组学
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全球变暖减缓期陆地地表气温变化特征和CMIP5多模式的未来情景预估 被引量:11
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作者 何金海 詹丰兴 +1 位作者 祁莉 王迪 《大气科学》 CSCD 北大核心 2016年第1期33-45,共13页
2000年后全球气温的增温率显著下降,全球进入变暖减缓期。本文基于CRU(Climatic Research Unit)观测资料,分析讨论了2000年后全球及欧亚中高纬度地区全球变暖的减缓特征,评估了CMIP5(Coupled Model Intercomparison Project Phase 5... 2000年后全球气温的增温率显著下降,全球进入变暖减缓期。本文基于CRU(Climatic Research Unit)观测资料,分析讨论了2000年后全球及欧亚中高纬度地区全球变暖的减缓特征,评估了CMIP5(Coupled Model Intercomparison Project Phase 5)试验多模式对全球变暖减缓的模拟及未来气温变化预估。结果表明,2000年后全球陆地平均地面气温的增温率大幅下降至0.14°C(10 a)-1,仅为1976~1999年加速期增温率的一半。全球陆地13个区域中有9个地区的增温率小于2000年前,4个地区甚至出现了降温。其中以欧亚中高纬地区最为特殊。加速期(1976~1999年)增温率达到0.50°C(10 a)-1,为全球陆地最大,2000年后陡降至-0.17°C(10 a)-1,为全球最强降温区,为全球变暖的减缓贡献了49.13%。并且具有显著的季节依赖,减缓期冬季增温率下降了-2.68°C(10a)-1,而秋季升高了0.86°C(10 a)-1,呈现反位相变化特征。CMIP5多模式计划中仅BCC-CSM1.1在RCP2.6情景下和MRI-ESM1模式在RCP8.5下的模拟较好地预估了全球及欧亚中高纬地区在2000年后增温率的下降以及欧亚中高纬秋、冬温度的反位相变化特征。BCC-CSM1.1在RCP2.6情景下预估欧亚中高纬地区2012年后温度距平保持在1.2°C左右,2020年后跃至2°C附近振荡。而MRI-ESM1在RCP8.5情景下预估的欧亚中高纬度温度在2030年前一直维持几乎为零的增温率,之后迅速升高。 展开更多
关键词 全球变暖减缓 欧亚中高纬 CMIP5(Coupled Model Intercomparison PROJECT Phase 5)
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PBL在“教学系统设计”课程教学中的应用 被引量:14
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作者 杜世友 吴忠良 王毅 《中国电化教育》 CSSCI 北大核心 2011年第8期96-99,共4页
"教学系统设计"是一门教与学"两难"的必修课程,将PBL教学模式应用于该课程教学可以充分调动学生参与学习的积极性,提高学生的问题解决能力。经过探索,本文总结出了以"课前预习、项目实践,教师精讲、引导,学生... "教学系统设计"是一门教与学"两难"的必修课程,将PBL教学模式应用于该课程教学可以充分调动学生参与学习的积极性,提高学生的问题解决能力。经过探索,本文总结出了以"课前预习、项目实践,教师精讲、引导,学生项目报告,学生讨论、教师点评"为主要内容的"课下"+"课堂"的"教学系统设计"PBL教学模式,并对应用PBL教学模式需注意的问题做了讨论,最后对教学效果进行了总结。 展开更多
关键词 教学系统设计 Project—basedLeaHling 教学模式
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