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Data-driven methods for predicting the representative temperature of bridge cable based on limited measured data
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作者 WANG Fen DAI Gong-lian +2 位作者 HE Chang-lin GE Hao RAO Hui-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3168-3186,共19页
Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai... Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges. 展开更多
关键词 cable-stayed bridges representative temperature gradient boosted regression trees(GBRT)method field test limited measured data
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The Realization of Ecological Ideas of Economic Gardens——A Case Study of "Red ribbon" Park in Qinhuangdao City
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作者 王颖 孔繁德 《Journal of Landscape Research》 2009年第3期17-20,共4页
The aim of this study is to analyze the ecological ideas of local habitat conservation,least intervention and concise ecological design in the design of Red Ribbon Park,and meanwhile put forward the suggestion that th... The aim of this study is to analyze the ecological ideas of local habitat conservation,least intervention and concise ecological design in the design of Red Ribbon Park,and meanwhile put forward the suggestion that the ecosystem health level of Tanghe River should be promoted as a whole. 展开更多
关键词 Tanghe River ZONAL PARK Red RIBBON ECOLOGICAL ideas ECONOMIC gardens ECOSYSTEM health
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On Application of Mathematic Idea and Method in English Grammar Teaching and Learning
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作者 李海 《海外英语》 2011年第1X期35-37,共3页
English grammar is at any time the important part of English learning,even if under the implementation of the New Course Standard.However,English grammar is considered to be difficult due to its complexity.My paper he... English grammar is at any time the important part of English learning,even if under the implementation of the New Course Standard.However,English grammar is considered to be difficult due to its complexity.My paper here is to explore and study the application of mathematic ideas and methods in English grammar teaching and learning,helping to facilitate the students to master the regularities,accuracy and systematization of English grammar,to improve learning efficiency,to enhance the learners' logic thinking,and at the same time,pointing out the specific strategies in practical use,which can be of great significance to the students' innovation and creativity and the students' development of the ability of cross-subject study advocated by both the Quality-Education and New Curriculum Standard. 展开更多
关键词 mathematic ideas and methods English GRAMMAR APPLICATION specific strategies FEASIBILITY and significance
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From Major-Countries Coordination to Global Mechanisms:an Analysis of the Global Governance of Large AI Models
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作者 Gao Qiqi 《Contemporary World》 2024年第4期5-9,共5页
The global governance of large artificial intelligence(AI)models calls for urgent actions.Large models,representing a type of technological innovation,is advancing global technological progress and is also compelling ... The global governance of large artificial intelligence(AI)models calls for urgent actions.Large models,representing a type of technological innovation,is advancing global technological progress and is also compelling the international community’s attention to the role of global governance system in coordinating the development of AI.In building a global governance mechanism for large models,both traditional governance system and new international system should be explored to construct Regime Complexes for the governance of large models. 展开更多
关键词 system representing TECHNOLOGICAL
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Assessing the impact of climate change on agricultural production in central Afghanistan
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作者 Homayoon RAOUFI Hamidreza JAFARI +1 位作者 Wakil Ahmad SARHADI Esmail SALEHI 《Regional Sustainability》 2024年第3期12-23,共12页
Afghanistan has faced extreme climatic crises such as drought,rising temperature,and scarce precipitation,and these crises will likely worsen in the future.Reduction in crop yield can affect food security in Afghanist... Afghanistan has faced extreme climatic crises such as drought,rising temperature,and scarce precipitation,and these crises will likely worsen in the future.Reduction in crop yield can affect food security in Afghanistan,where the majority of population and economy are completely dependent on agriculture.This study assessed the interaction between climate change and crop yield in Kabul of Afghanistan during the reference(1990–2020)and future(2025–2100)periods.Climate data(1990–2020)were collected from four meteorological stations and three local organizations,and wheat yield data(1990–2020)were acquired from the United States Agriculture Department.Data during the reference period(1990–2020)were used for the validation and calibration of the statistical downscaling models such as the Statistical Downscaling Model(SDSM)and Long Ashton Research Station Weather Generator(LARS-WG).Furthermore,the auto-regression model was used for trend analysis.The results showed that an increase in the average annual temperature of 2.15℃,2.89℃,and 4.13℃will lead to a reduction in the wheat yield of 9.14%,10.20%,and 12.00%under Representative Concentration Pathway(RCP)2.6,RCP4.5,and RCP8.5 during the future period(2025–2100),respectively.Moreover,an increase in the annual maximum temperature of 1.79℃,2.48℃,and 3.74℃also causes a significant reduction in the wheat yield of 2.60%,3.60%,and 10.50%under RCP2.6,RCP4.5,and RCP8.5,respectively.Furthermore,an increase in the annual minimum temperature of 2.98℃,2.23℃,and 4.30℃can result in an increase in the wheat yield of 6.50%,4.80%,and 9.30%under RCP2.6,RCP4.5,and RCP8.5,respectively.According to the SDSM,the decrease of the average monthly precipitation of 4.34%,4.10%,and 5.13%results in a decrease in the wheat yield of 2.60%,2.36%,and 3.18%under RCP2.6,RCP4.5,and RCP8.5,respectively.This study suggests that adaptation strategies can be applied to minimize the consequences of climate change on agricultural production. 展开更多
关键词 Climate change Wheat yield Food security representative Concentration Pathway(RCP) AFGHANISTAN
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Intention and Standing Image:Interpretation of the Aesthetic Intention of Arhat Portrait on Mount Wutai
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作者 LI Lei 《Journal of Literature and Art Studies》 2024年第9期749-758,共10页
Mount Wutai,a place endowed with fine spirits of humanities and prolific remains of Arhats portrait art.The existing Mount Wutai Arhats portrait spans the Ming,Qing,and Republic of China periods,and through the artist... Mount Wutai,a place endowed with fine spirits of humanities and prolific remains of Arhats portrait art.The existing Mount Wutai Arhats portrait spans the Ming,Qing,and Republic of China periods,and through the artistic creation of successive generations of literati painters,exquisite Arhats portraits are painted on different artistic carriers.On the basis of inheriting the traditional Chinese paradigm painting expression,the portrait of Mount Wutai Arhats constantly draws on folk nutrients.It integrates foreign Buddhist culture for refinement and sublimation.The reconstructed portrait pays attention to the image expression of its objects and the shaping of spiritual temperament.The shape is ancient and vivid,and the scene is ethereal and mysterious,which rationally expresses the Buddhist philosophy of generosity,benevolence and kindness,and contains unique oriental aesthetics. 展开更多
关键词 Buddhist art Portrait of Arhats aesthetic idea
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Multidimensional Perspectives on the Teaching and Practice of Typography Design
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作者 Chen Kun Xiao Daibo +2 位作者 Kuang Xiuxin Xie Hao Wu Can 《教育技术与创新》 2024年第3期1-13,共13页
With the deepening of the curriculum teaching reform in colleges and universities,the teaching reform of art design professional courses is imperative.The study found that the current art design professional font desi... With the deepening of the curriculum teaching reform in colleges and universities,the teaching reform of art design professional courses is imperative.The study found that the current art design professional font design course teaching there are more solidified teaching methods,students operating ability is relatively homogenised,the teaching content to the"westernised"based,resulting in poor adaptability of students and other prominent problems.This paper starts from the"three effects"of"effect","efficiency"and"effectiveness",and adopts a multi-dimensional and emotional thinking perspective to carry out the curriculum of typeface design.This paper starts from the"three effects"of"effect","efficiency"and"effectiveness",and adopts a multi-dimensional and emotional perspective of thinking to carry out the teaching and practice of typeface design in order to strengthen the visual information of Chinese culture,and at the same time,to explore the creative potential of the students,so as to improve the students'innovation and creativity. 展开更多
关键词 Multidimensional Perspective Typography Design Course Teaching Improvement ideas
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An Evaluation of the Critical Success Factors in Sustainable Food Supply Chains in Developing Countries
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作者 Muhammad Ahasan Habib Deen Islam Preyo +1 位作者 Muhammad Kamruzzaman Ahasan Md. Maruf Hossain 《World Journal of Engineering and Technology》 2024年第3期466-492,共27页
Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcin... Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcing and the growing technological, social, and environmental concerns. The food business faces serious sustainability and growth challenges in developing countries. A comprehensive analysis of the critical success factors (CSFs) influencing the performance outcome and the sustainable supply chain management (SSCM) process. A theoretical framework is established to explain how they are used to examine the organizational aspect of the food supply chain life cycle analysis. This study examined the CSFs and revealed the relationships between them using a methodology that included a review of literature, interpretative structural modeling (ISM), and cross-impact matrix multiplication applied in classification (MICMAC) tool analysis of soil liquefaction factors. The findings of this research demonstrate that the quality and safety of food are important factors and have a direct effect on other factors. To make sustainable food supply chain management more adequate, legislators, managers, and experts need to pay attention to this factor. In this work. It also shows that companies aiming to create a sustainable business model must make sustainability a fundamental tenet of their organization. Practitioners and managers may devise effective long-term plans for establishing a sustainable food supply chain utilizing the recommended methodology. 展开更多
关键词 Supply Chain Collaboration Interpretative Structural Modeling Cross-Impact Matrix Multiplication SUSTAINABILITY Critical Success Factors Multi-Criteria Decision Making Technique for Order of Preference by Similarity to idea Solution
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Understanding the spatial representativeness of air quality monitoring network and its application to PM_(2.5)in the China's Mainland 被引量:3
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作者 Ling Su Chanchan Gao +7 位作者 Xiaoli Ren Fengying Zhang Shanshan Cao Shiqing Zhang Tida Chen Mengqing Liu Bingchuan Ni Min Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第3期130-138,共9页
Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regi... Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regional air pollutants.The spatial representativeness of AQMS is a critical parameter when choosing the location of stations and assessing effects on the population to long-term exposure to air pollution.In this paper,we proposed a methodological framework for assessing the spatial representativeness of the regional air quality monitoring network and applied it to ground-based PM_(2.5)observation in the mainland of China.Weighted multidimensional Euclidean distance between each pixel and the stations was used to determine the representativeness of the existing monitoring network.In addition,the K-means clustering method was adopted to improve the spatial representativeness of the existing AQMS.The results showed that there were obvious differences among the representative area of 1820 stations in the mainland of China.The monitoring stations could well represent the PM_(2.5)spatial distribution of the entire region,and the effectively represented area(i.e.the area where the Euclidean distance between the pixels and the stations was lower than the average value)accounted for 67.32%of the total area and covered 93.12%of the population.Forty additional stations were identified in the Northwest,North China,and Northeast regions,which could improve the spatial representativeness by 14.31%. 展开更多
关键词 PM_(2.5) Euclidean distance Spatial representativeness China
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Representative value of cross-fault in the northeastern margin of the Qinghai-Tibet block and case analysis of the 2016 Menyuan Ms6.4 earthquake 被引量:1
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作者 Ruisha Li Xi Zhang +2 位作者 Shouwen Gong Hongtao Tang Peng Jia 《Geodesy and Geodynamics》 2016年第4期268-274,共7页
The equation for determining cross-fault representative value is calculated based on hanging wall and foot wall reference level surfaces. The cross-fault data reliability are analyzed base on the stability of referenc... The equation for determining cross-fault representative value is calculated based on hanging wall and foot wall reference level surfaces. The cross-fault data reliability are analyzed base on the stability of reference datum and observation points, thereby facili- tating plotting of the representative value curves after removing interference. The spatial and temporal characteristics of fault deformation abnormalities before the 2016 Menyuan Ms6.4 earthquake, as well as the fault-movement characteristics reflected by representa- tive value, are summarized. The results show that many site trends had changed 1-3 years before the Menyuan Ms6.4 earthquake in the Qilian Fault, reflecting certain background abnormalities. The short-term abnormalities centrally had appeared in the 6 months to 1 year period before the earthquake near and in the neighborhood of the source region, demonstrating a significantly increased number of short-term abnormalities. Many sites near and in the neighborhood of the source region had strengthened inverse activities or had changed from positive to inverse activities in the most recent 2-3 years, which reflect stress-field enhancements or adjustment features. 展开更多
关键词 Northeastern margin of Qinghai- Tibet representative value of cross-faul t Menyuan Ms6.4 earthquake Fault activity Precursor Reference datum Stability
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Three-dimensional spatial structure of the macro-pores and flow simulation in anthracite coal based on X-ray μ-CT scanning data 被引量:3
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作者 Hui-Huang Fang Shu-Xun Sang Shi-Qi Liu 《Petroleum Science》 SCIE CAS CSCD 2020年第5期1221-1236,共16页
The three-dimensional(3 D) structures of pores directly affect the CH4 flow.Therefore,it is very important to analyze the3 D spatial structure of pores and to simulate the CH4 flow with the connected pores as the carr... The three-dimensional(3 D) structures of pores directly affect the CH4 flow.Therefore,it is very important to analyze the3 D spatial structure of pores and to simulate the CH4 flow with the connected pores as the carrier.The result shows that the equivalent radius of pores and throats are 1-16 μm and 1.03-8.9 μm,respectively,and the throat length is 3.28-231.25 μm.The coordination number of pores concentrates around three,and the intersection point between the connectivity function and the X-axis is 3-4 μm,which indicate the macro-pores have good connectivity.During the single-channel flow,the pressure decreases along the direction of CH4 flow,and the flow velocity of CH4 decreases from the pore center to the wall.Under the dual-channel and the multi-channel flows,the pressure also decreases along the CH4 flow direction,while the velocity increases.The mean flow pressure gradually decreases with the increase of the distance from the inlet slice.The change of mean flow pressure is relatively stable in the direction horizontal to the bedding plane,while it is relatively large in the direction perpendicular to the bedding plane.The mean flow velocity in the direction horizontal to the bedding plane(Y-axis) is the largest,followed by that in the direction horizontal to the bedding plane(X-axis),and the mean flow velocity in the direction perpendicular to the bedding plane is the smallest. 展开更多
关键词 X-rayμ-CT representative elementary volume Pore network model Geometric and topological structures Flow simulation COMSOL
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Three Phase Composite Cylinder Assemblage Model for Analyzing the Elastic Behavior of MWCNT-Reinforced Polymers 被引量:1
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作者 Puneet Kumar J.Srinivas 《Computers, Materials & Continua》 SCIE EI 2018年第1期1-20,共20页
Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube(CNT)reinforced polymer composites recently.This paper presents the composite cylinder as... Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube(CNT)reinforced polymer composites recently.This paper presents the composite cylinder assemblage(CCA)approach based on continuum mechanics for investigating the elastic properties of a polymer resin reinforced by multi-walled carbon nanotubes(MWCNTs).A three-phase cylindrical representative volume element(RVE)model is employed based on CCA technique to elucidate the effects of inter layers,chirality,interspacing,volume fraction of MWCNT,interphase properties and temperature conditions on the elastic modulus of the composite.The interface region between CNT and polymer matrix is modeled as the third phase with varying material properties.The constitutive relations for each material system have been derived based on solid mechanics and proper interfacial traction continuity conditions are imposed.The predicted results from the CCA approach are in well agreement with RVE-based finite element model.The outcomes reveal that temperature softening effect becomes more pronounced at higher volume fractions of CNTs. 展开更多
关键词 Multi-walled carbon nanotube composite cylinder assemblage CONTINUUM representative volume element variable interphase
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Analysing the behavioural finance impact of ‘fake news’phenomena on financial markets:a representative agent model and empirical validation 被引量:1
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作者 Bryan Fong 《Financial Innovation》 2021年第1期1169-1198,共30页
This paper proposes an original behavioural finance representative agent model,to explain how fake news’empirical price impacts can persist in finance despite contradicting the efficient-market hypothesis.The model r... This paper proposes an original behavioural finance representative agent model,to explain how fake news’empirical price impacts can persist in finance despite contradicting the efficient-market hypothesis.The model reconciles empirically-observed price overreactions to fake news with empirically-observed price underreactions to real news,and predicts a novel secondary impact of fake news:that fake news in a security amplifies underreactions to subsequent real news for the security.Evaluating the model against a large-sample event study of the 2019 Chinese ADR Delisting Threat fake news and debunking event,this paper finds strong qualitative validation for its model’s dynamics and predictions. 展开更多
关键词 Behavioural finance Fake news representative agent model Event study BOOTSTRAPPING
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COADJOINT ORBITS FOR THE CENTRAL EXTENSION OF Diff^+(S^1) AND THEIR REPRESENTATIVES
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作者 戴佳玲 Doug pickrell 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期185-205,共21页
According to Kirillov's idea, the irreducible unitary representations of a Lie group G roughly correspond to the coadjoint orbits (?).In the forward direction one applies the methods of geometric quantization to p... According to Kirillov's idea, the irreducible unitary representations of a Lie group G roughly correspond to the coadjoint orbits (?).In the forward direction one applies the methods of geometric quantization to produce a representation, and in the reverse direction one computes a transform of the character of a representation, to obtain a coadjoint orbit. The method of orbits in the representations of Lie groups suggests the detailed study of coadjoint orbits of a Lie group G in the space (?)~* dual to the Lie algebra (?) of G. In this paper, two primary goals are achieved: one is to completely classify the smooth coadjoint orbits of Virasoro group for nonzero central charge c; the other is to find representatives for coadjoint orbits. These questions have been considered previously by Segal, Kirillov, and Witten, but their results are not quite complete. To accomplish this, the authors start by describing the coadjoint action of D-the Lie group of all orientation preserving diffeomorphisms on the circle S^1, and its central extension (?), then the authors will give a complete classification of smooth coadjoint orbits. In fact, they can be parameterized by a subspace Of conjugacy classes of (?)(1,1). Finally, the authors will show how to find representatives f coadjoint orbits by analyzing the vector fields stabilizing the orbits, and describe the amazing connection between the characteristic (trace) of conjugacy classes of (?)(1, 1) and that of vector fields stabilizing orbits. 展开更多
关键词 Coadjoint representations coadjoint orbits STABILIZERS vector fields representatives
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On the Angular Distribution of the Representative Points of Bases of Human Protein Coding Sequences
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作者 Zhou Guoxiang Wang Aikun He Wenchen(Mathematics and Physics Department,Hebei University of Technology, 300130, Tianjin, China) 《河北工业大学学报》 CAS 1997年第A01期1-4,共4页
A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture i... A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture is clearer and more intuitive than that in [1] .A rule on the angular distribution of the representative points of bases of protein sequences is given. Besides, in 300 representative pointS of human protein sequence samples we find that there are three (not only one) points outside the sphere. 展开更多
关键词 ANGULAR DISTRIBUTION representative point of BASES of protein CODING sequence/ DISTRIBUTION SPHERE
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Minimum Representative Size in Comparing Research Performance of Universities:the Case of Medicine Faculties in Romania
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作者 Xiaoling Liu Mihai Paunescu +1 位作者 Viorel Proteasa Jinshan Wu 《Journal of Data and Information Science》 CSCD 2018年第3期32-42,共11页
Purpose: The main goal of this study is to provide reliable comparison of performance in higher education. In this respect, we use scientometric measures associated with faculties of medicine in the six health studie... Purpose: The main goal of this study is to provide reliable comparison of performance in higher education. In this respect, we use scientometric measures associated with faculties of medicine in the six health studies universities in Romania.Design/methodology/approach: The method to estimate the minimum necessary size, proposed in in Shen et al.(2017), is applied in this article. We collected data from the Scopus data-base for the academics of the departments of medicine within the six health studies universities in Romania during the 2009 to 2014. And two kind of statistic treatments based on that method are implemented, pair-wise comparison and one-to-the-rest comparison. All the results of these comparisons are shown.Findings: According to the results: We deem that Cluj and Tg. Mure? have the superior and inferior performance respectively, since their reasonably small value of the minimum representative size, in either of the kinds of comparison, whichever indexes of citations, h-index, or g-index is used. we can not reliably distinguish differences among the rest of the faculties, since the quite large value of their minimum representative size.Research limitations: There is only six faculties of medicine in health studies universities in Romania are analyzed.Practical implications: Our methods of comparison play an important role in ranking data sets associated with different collective units, such as faculties, universities, institutions, based on some aggregate scores like mean and totality. Originality/value: We applied the minimum representative size to a new emprical context- that of the departments of medicine in the health studies universities in Romania. 展开更多
关键词 Research evaluation Minimum representative size Bootstrap sampling Medicine departments
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Idea and goals of environmental protection and ecological construction in the 11^(th) five-year plan period 被引量:2
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作者 Liu Yuanqing Su Yang 《Ecological Economy》 2006年第1期69-76,共8页
In this paper, the executive of the 10th Five- Year Plan in the field of environmental protection and ecological constrution is reviewed, and the charactristics of economic growth and its environmental impact on the 1... In this paper, the executive of the 10th Five- Year Plan in the field of environmental protection and ecological constrution is reviewed, and the charactristics of economic growth and its environmental impact on the 11^th Five-Year Plan is forecasted and analyzed. A principal idea of eavironmental protection and ecological construction is put forward for the 11^th Five-Year Plan pertod: strensgthen the point treatment in key areas and set the main targets based on the idea. The relating countermeasures in national level are proposed as follows: set up appropriate ideas for official achievements by launching resources and environmental cost acconting; adjust the industrial struacture actively by industrial policies and strenuous work; develop circular economy, change the mode of environmental protecgon from end treatment to headstream and proeess control: strengthen the market mechanism in the process of pollution treatment, set up the system of "who treats who benefits" ; perfect interrelated laws and standards, strengthen the ability of environmental munagement; lay extra emphasis on two key targets: water pollution tretment in key river basins and management of the reserves; and combine the ecological consnuction and poverty alleviation in higher level. 展开更多
关键词 the H th Five- Year Plan: Environmental protection Principal idea Countermeasures in national level
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District Partisan Homogeneity, Communications, and the Electoral Motive: An Analysis of the Facebook Posts of Members of the U.S. House of Representatives
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作者 Scot Schraufnagel Quan Li Adam Schuster 《Social Networking》 2017年第2期148-163,共16页
The research examines the way in which members of the U.S. House of Representative represent themselves on the social network site Facebook. Each member’s activity is observed on seven different occasions and the fre... The research examines the way in which members of the U.S. House of Representative represent themselves on the social network site Facebook. Each member’s activity is observed on seven different occasions and the frequency and substantive character of posts made during the second half of 2013 are established. The focus is on position-taking posts versus posts which mention the district the member serves in. Our expectation is that members from electorally safe districts will be more likely to advertise their policy positions while members from marginal districts will be more inclined to advertise their district connections. We control for minority party status, gender, and ideological extremism among other concerns and learn electoral safety is a good predictor of both “position-taking” and “district mentions”. Consistent with an electoral motive, we also find members from the minority party less likely to take positions on the issues of the day and more likely to mention the district they serve in. 展开更多
关键词 U.S. House of representatives FACEBOOK POSTS Electoral Motives CREDIT Claiming
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Applications-Some Influences of Engineering Ideas on Biology Being the fifth in a series of essays on the materials of nature 被引量:1
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作者 Julian F.V.Vincent 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第2期99-114,共16页
Ideas from engineering have helped the understanding of biological organisms for thousands of years. However, the mechanical aspects of biological materials and structures can, if properly interpreted and analysed, le... Ideas from engineering have helped the understanding of biological organisms for thousands of years. However, the mechanical aspects of biological materials and structures can, if properly interpreted and analysed, lead to a deeper understanding of the biology of organisms. Such an approach, although always current in some form, is nevertheless subject to the vagaries of fashion and the availability of analytical techniques. At present we are in a period of upturn. Areas of interest are deployable structures (applications in aerospace), palaeontology (how little do we need to know in order to create a credible biosphere) and food science (we need a rational approach to the mechanics of food). 展开更多
关键词 Applications-Some Influences of Engineering ideas on Biology Being the fifth in a series of essays on the materials of nature
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Representativeness of suspected measles cases reported in a southern district of Nigeria
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作者 Akinola A Fatiregun Chuks C Odega 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第2期153-156,共4页
Objective:To compare the characteristics of suspected measles cases at the health facilities and to determine the representativeness of the data.Methods:We visited 25 hospitals in the Aniocha Local Government Area(LGA... Objective:To compare the characteristics of suspected measles cases at the health facilities and to determine the representativeness of the data.Methods:We visited 25 hospitals in the Aniocha Local Government Area(LGA) of Delta State,Nigeria,from which information on reportable diseases was collected.In particular,the suspected measles cases in their registries between January 1,2007,and June 30,2008,were reviewed.We compared the characteristics,including age,sex,location,and month of reporting,of the suspected cases with the LGA surveillance records.Results:In the LGA records,10%cases involved individuals older than 14 years, compared with 20%in the same age group in the health facility records.Based on geographic location,53%of the measles cases among the hospital records came from a single location,in contrast to only 30%of the cases among the LGA records.An analysis considering time revealed that 30%of the cases in the LGA records occurred in August 2007,whereas 20%of hospital cases were reported in February and May 2008 combined.Conclusions:The two record types differed considerably in all of the characteristics used in this comparison. 展开更多
关键词 representativeness of data Suspected measles Surveillance evaluation NIGERIA
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