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Trust model based on individual experience
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作者 王少杰 郑雪峰 +2 位作者 初俐君 于真 徐光美 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期373-376,共4页
To improve the accuracy of node trust evaluation in a distributed network, a trust model based on the experience of individuals is proposed, which establishes a new trust assessment system by introducing the experienc... To improve the accuracy of node trust evaluation in a distributed network, a trust model based on the experience of individuals is proposed, which establishes a new trust assessment system by introducing the experience factor and the comparative experience factor. The new evaluation system considers the differences between individuals and interactive histories between nodes, which solves the problem that nodes have inaccurate assessments due to the asymmetry of nodes to a certain extent. The algorithm analysis indicates that the new model uses different deviating values of tolerance evaluation for different individuals and uses different updating values embodying node individuation when updating feedback credibility of individuals, which evaluates the trust value more reasonably and more accurately. In addition, the proposed algorithm can be used in various trust models and has a good scalability. 展开更多
关键词 trust model individual experience feedback trust value
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Modeling and simulation for individualized therapy of amisulpride in Chinese patients with schizophrenia:focus on inter interindi⁃vidual variability,therapeutic reference range and laboratory alert level 被引量:4
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作者 HUANG Shan-qing LI Lu +7 位作者 WANG Zhan-zhang XIAO Tao LI Xiao-lin LIU Shu-jing ZHANG Ming LU Hao-yang WEN Yu-guan SHANG De-wei 《中国药理学与毒理学杂志》 CAS 北大核心 2021年第9期661-662,共2页
OBJECTIVE To explain the high inter-individual variability and the frequency of exceeding the therapeutic reference range and the laboratory alert level of amisulpride,a popula⁃tion pharmacokinetic model in Chinese pa... OBJECTIVE To explain the high inter-individual variability and the frequency of exceeding the therapeutic reference range and the laboratory alert level of amisulpride,a popula⁃tion pharmacokinetic model in Chinese patients with schizophrenia was built based on therapeu⁃tic drug monitoring data to guide individualized therapy.METHODS Plasma concentration data(330 measurements from 121 patients)were ana⁃lyzed using a nonlinear mixed-effects model⁃ing approach with first-order conditional estima⁃tion with interaction(FOCE I).The concentra⁃tions of amisulpride were detected by HPLC-MS/MS.Age,weight,sex,combination medication history and renal function status were evaluated as main covariates.The model was internally val⁃idated using goodness-of-fit,bootstrap and nor⁃malized prediction distribution error.Recom⁃mended dosage regimens for patients with key covariates were estimated on the basis of Monte Carlo simulations and the established model.RESULTS A one-compartment model with first-order absorption and elimination was found to adequately characterize amisulpride concentra⁃tion in Chinese patients with schizophrenia.The population estimates of the apparent volume of distribution(V/F)and apparent clearance(CL/F)were 12.7 L and 1.12 L·h-1,respectively.Age sig⁃nificantly affected the clearance of amisulpride and the final model was as follow:CL/F=1.04×(AGE/32)-0.624(L·h-1).To avoid exceeding the lab⁃oratory alert level(640μg·L-1),the model-based simulation results showed that the recommended dose of amisulpride was no more than 600 mg per day for patients aged 60 years,800 mg per day for those aged 40 years and 1200 mg per day for those aged 20 years,respectively.CON⁃CLUSION Dosage optimization of amisulpride can be carried out according to age to reduce the risk of adverse reactions.The model can be used as a suitable tool for designing individual⁃ized therapy for Chinese patients with schizo⁃phrenia. 展开更多
关键词 AMISULPRIDE population pharmacoki⁃netics therapeutic drug monitoring modeling and simulation individualized therapy
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Modeling and Analyzing Dynamic Response for An Offshore Bottom-Fixed Wind Turbine with Individual Pitch Control 被引量:1
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作者 XIE Shuang-yi ZHANG Kai-fei +2 位作者 HE Jiao GAO Jian ZHANG Cheng-lin 《China Ocean Engineering》 SCIE EI CSCD 2022年第3期372-383,共12页
The asymmetric or periodically varying blade loads resulted by wind shear become more significant as the blade length is increased to capture more wind power.Additionally,compared with the onshore wind turbines,their ... The asymmetric or periodically varying blade loads resulted by wind shear become more significant as the blade length is increased to capture more wind power.Additionally,compared with the onshore wind turbines,their offshore counterparts are subjected to additional wave loadings in addition to wind loadings within their lifetime.Therefore,vibration control and fatigue load mitigation are crucial for safe operation of large-scale offshore wind turbines.In view of this,a multi-body model of an offshore bottom-fixed wind turbine including a detailed drivetrain is established in this paper.Then,an individual pitch controller(IPC)is designed using disturbance accommodating control.State feedback is used to add damping in flexible modes of concern,and a state estimator is designed to predict unmeasured signals.Continued,a coupled aero-hydro-servo-elastic model is constructed.Based on this coupled model,the load reduction effect of IPC and the dynamic responses of the drivetrain are investigated.The results showed that the designed IPC can effectively reduce the structural loads of the wind turbine while stabilizing the turbine power out-put.Moreover,it is found that the drivetrain dynamic responses are improved under IPC. 展开更多
关键词 wind turbine individual pitch controller disturbance accommodating control multi-body modeling drivetrain
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Modelling the Effect of Self-Immunity and the Impacts of Asymptomatic and Symptomatic Individuals on COVID-19 Outbreak 被引量:1
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作者 M.H.A.Biswas M.A.Islam +5 位作者 S.Akter S.Mandal M.S.Khatun S.A.Samad A.K.Paul M.R.Khatun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期1033-1060,共28页
COVID-19 is one of themost highly infectious diseases ever emerged and caused by newly discovered severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).It has already led the entire world to health and economic ... COVID-19 is one of themost highly infectious diseases ever emerged and caused by newly discovered severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).It has already led the entire world to health and economic crisis.It has invaded the whole universe all most every way.The present study demonstrates with a nine mutually exclusive compartmental model on transmission dynamics of this pandemic disease(COVID-19),with special focus on the transmissibility of symptomatic and asymptomatic infection from susceptible individuals.Herein,the compartmental model has been investigated with mathematical analysis and computer simulations in order to understand the dynamics of COVID-19 transmission.Initially,mathematical analysis of the model has been carried out in broadly by illustrating some well-known methods including exactness,equilibrium and stability analysis in terms of basic reproduction number.We investigate the sensitivity of the model with respect to the variation of the parameters’values.Furthermore,computer simulations are performed to illustrate the results.Our analysis reveals that the death rate from coronavirus disease increases as the infection rate increases,whereas infection rate extensively decreases with the increase of quarantined individuals.The quarantined individuals also lead to increase the concentration of recovered individuals.However,the infection rate of COVID-19 increases more surprisingly as the rate of asymptomatic individuals increases than that of the symptomatic individuals.Moreover,the infection rate decreases significantly due to increase of self-immunity rate. 展开更多
关键词 COVID-19 asymptomatic and symptomatic individuals selfimmunity mathematical model basic reproductive ratio numerical simulations
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Lewin Behavior Model-Based Study on Influence Factors of Individuals to Mobile Service Demand 被引量:1
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作者 Tong Lili, Li Xiaowen 《China Communications》 SCIE CSCD 2012年第6期154-162,共9页
How to fmd main influence factors of individuals to mobile service demand is investiga- ted. The empirical research is conducted in the sample of high-value customers in China mobile market. Based on Lewin behavior mo... How to fmd main influence factors of individuals to mobile service demand is investiga- ted. The empirical research is conducted in the sample of high-value customers in China mobile market. Based on Lewin behavior model, this pa- per establishes factors-matrix from personal and environmental dimensions. Relationships among multiple factors are tested in the structural equa- tion model and their impacts on customers' de- mands are elaborated. Findings indicate that opera- tional convenience and business brand image have significant effects on sample users' demands. Fur- thermore, annual income, gender, occupation, the needs of access to information and the needs of enriching and improving social relationships are al- so important factors for high-value users. The re- suits may provide further insights into mobile service demand and the model can be popularized to other behavior researches. 展开更多
关键词 individuals' behavior research distin-guish path Lewin behavior model influence fac-tors mobile service demand
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Development and evaluation of an individual tree growth and yield model for the mixed species forest of the Adirondacks Region of New York, USA
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作者 Aaron Weiskittel Christian Kuehne +1 位作者 John Paul McTague Mike Oppenheimer 《Forest Ecosystems》 SCIE CSCD 2017年第1期66-82,共17页
Background: Growth and yield models are important tools for forest planning. Due to its geographic location, topology, and history of management, the forests of the Adirondacks Region of New York are unique and compl... Background: Growth and yield models are important tools for forest planning. Due to its geographic location, topology, and history of management, the forests of the Adirondacks Region of New York are unique and complex. However, only a relatively limited number of growth and yield models have been developed and/or can be reasonably extended to this region currently. Methods: in this analysis, 571 long-term continuous forest inventory plots with a total of 10 - 52 years of measurement data from four experimental forests maintained by the State University of New York College of Environmental Science and Forestry and one nonindustrial private forest were used to develop an individual tree growth model for the primary hardwood and softwood species in the region. Species-specific annualized static and dynamic equations were developed using the available data and the system was evaluated for long-term behavior. Results: Equivalence tests indicated that the Northeast Variant of the Forest Vegetation Simulator (FVS-NE) was biased in its estimation of tree total and bole height, diameter and height increment, and mortality for most species examined. In contrast, the developed static and annualized dynamic, species-specific equations performed quite well given the underlying variability in the data. Long-term model projections were consistent with the data and suggest a relatively robust system for prediction. Conclusions: Overall, the developed growth model showed reasonable behavior and is a significant improvement over existing models for the region. The model also highlighted the complexities of forest dynamics in the region and should help improve forest planning efforts there. 展开更多
关键词 individual tree growth model Mixed species Forest vegetation simulator
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An imputation/copula-based stochastic individual tree growth model for mixed species Acadian forests: a case study using the Nova Scotia permanent sample plot network
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作者 John A. Kershaw Jr Aaron R. Weiskittel +1 位作者 Michael B. Lavigne Elizabeth McGarrigle 《Forest Ecosystems》 SCIE CSCD 2017年第4期251-263,共13页
Background: A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection... Background: A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection system. Methods: The Nova Scotia, Canada permanent sample plot network is used as a case study to develop and test the modelling approach. Predictions from this model are compared to predictions from the Acadian variant of the Forest Vegetation Simulator, a widely used statistical individual tree growth and yield model. Results: Diameter and height growth rates were predicted with error rates consistent with those produced using statistical models. Mortality and ingrowth error rates were higher than those observed for diameter and height, but also were within the bounds produced by traditional approaches for predicting these rates. Ingrowth species composition was very poorly predicted. The model was capable of reproducing a wide range of stand dynamic trajectories and in some cases reproduced trajectories that the statistical model was incapable of reproducing. Conclusions: The model has potential to be used as a benchmarking tool for evaluating statistical and process models and may provide a mechanism to separate signal from noise and improve our ability to analyze and learn from large regional datasets that often have underlying flaws in sample design. 展开更多
关键词 Nearest neighbor imputation Copula sampling individual tree growth model Mortality INGROWTH Mixed species stand development Acadian forests Nova Scotia
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Steady States in SIRS Epidemical Model of Mobile Individual
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作者 ZHANG Duan-Ming HE Min-Hua +7 位作者 YU Xiao-Ling PAN Gui-Jun SUN Hong-Zhang SU Xiang-Ying SUN Fan YIN Yah-Ping LI Rui LIU Dan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期105-108,共4页
We consider an epidemical model within soclally interacting mobile individuals to study the behaviors of steady states of epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations... We consider an epidemical model within soclally interacting mobile individuals to study the behaviors of steady states of epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations, we recover the usual epidemic behavior with critical thresholds δc and pc below which infectious disease dies out. For the population density δ far above δc it is found that there is linear relationship between contact rate λ and the population density δ in the main. At the same time, the result obtained from mean-field approximation is compared with our numerical result, and it is found that these two results are similar by and large but not completely the same. 展开更多
关键词 small world epidemical model mobile individual mean-field equation
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Quantitative Structural Models to Assess Credit Risk on Individuals
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作者 Akorede K. Oluwo Enrique Villamor 《Journal of Applied Mathematics and Physics》 2022年第7期2313-2340,共28页
Default Probabilities quantitatively measures the credit risk that a borrower will be unable or unwilling to repay its debt. An accurate model to estimate, as a function of time, these default probabilities is of cruc... Default Probabilities quantitatively measures the credit risk that a borrower will be unable or unwilling to repay its debt. An accurate model to estimate, as a function of time, these default probabilities is of crucial importance in the credit derivatives market. In this work, we adapt Merton’s [1] original works on credit risk, consumption and portfolio rules to model an individual wealth scenario, and apply it to compute this individual default probabilities. Using our model, we also compute the time depending individual default intensities, recovery rates, hazard rate and risk premiums. Hence, as a straight-forward application, our model can be used as novel way to measure the credit risk of individuals. 展开更多
关键词 Merton Structural model individual Default Intensities Hazard Rate for individuals individual Risk Premium
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Interpersonal Perception in Virtual Groups: Examining Homophily, Identification and Individual Attraction Using Social Relations Model in Network
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作者 Zuoming Wang 《Social Networking》 2023年第2期45-56,共12页
With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social rela... With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social relations model (SRM) [1], this paper investigates interpersonal perception in virtual groups from a multilevel perspective. In particular, it examines the following three areas: homophily, identification, and individual attraction, and explores how much of these directional and dyadic relational evaluations can be attributed to the effect of the actor, the partner, and the relationship. 展开更多
关键词 Virtual Groups Interpersonal Perception Social Relations model HOMOPHILY IDENTIFICATION individual Attraction
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The Game Model Analysis between the Individual and the Group
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作者 Dehai Liu Dagang Wang Shulin Liu 《Chinese Business Review》 2004年第2期29-32,共4页
This paper analyses the game model between the individual and the group that has the characteristics of Stackelberg model in traditional game theory and replicator dynamic model in evolutionary game theory. In the fir... This paper analyses the game model between the individual and the group that has the characteristics of Stackelberg model in traditional game theory and replicator dynamic model in evolutionary game theory. In the first phase of game, the bounded rationality group players adopt the replicator dynamic behavior. Secondly, the full rationality individual player decides the own response function by the strategies distribution of group players. The shortsighted individual player will take the risk-dominant strategy. This model has some unique characteristics. 展开更多
关键词 the individual and the group Stackelberg model replicator dynamic group decision-making
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Individual and Systemic Factors of Under-five Mortality in Nigeria:A Cox Proportional Hazard Model
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作者 Titus Kolawole Ojewumi 《Macro Management & Public Policies》 2023年第3期16-33,共18页
Despite considerable efforts to reduce under-five mortality nationwide,Nigeria has fallen short of achieving the Millennium Development Goals(MDGs)target of 67 deaths per 1,000 live births by 2015.Of all the documente... Despite considerable efforts to reduce under-five mortality nationwide,Nigeria has fallen short of achieving the Millennium Development Goals(MDGs)target of 67 deaths per 1,000 live births by 2015.Of all the documented factors of under-five mortality,little evidence exists on the impact of systemic barriers and individual factors(maternal health-seeking behaviour)on under-five mortality in Nigeria.The study used a nationally representative sample from Nigeria Demographic and Health Survey(NDHS)2013 dataset.The target population was 20,192 women aged 15-59 years who had given birth to 31,480 children five years before the survey.Stata software was used for data analysis.The risk of death was estimated using Cox proportional hazard models and results are presented as hazards ratios(HR)with 95%confidence intervals(CI).Findings from the overall Model I-IV revealed individual factors(maternal health-seeking indicators)as significant factors of under-five deaths(p<0.05).Children whose mothers received antenatal care coverage(ANC)outside health care facilities(HCF)(HR:1.60,CI:1.0-2.4,p<0.05);or delivered outside HCF(HR:1.02,CI:0.7-1.5,p<0.05)had elevated hazard risk of death before age five.Conversely,children who were presented for postnatal check within two weeks of delivery(HR:0.60,CI:0.5-0.8,p<0.05),or delivered within the longer birth interval(HR:0.67,CI:0.6-0.8,p<0.001)had significantly lower hazard risk of death before age five.As part of systemic factors,children whose mothers were covered by health insurance scheme had significantly(HR:0.52,CI:0.2-1.2,p<0.001)lower risk of death when compared with their counterparts without health insurance coverage.The study emphasized the need to revitalize strategies and programs to improve women health seeking behaviour and investment in the health sector through health insurance,infrastructure,and supplies. 展开更多
关键词 individual SYSTEMIC Under-five MORTALITY Cox-proportional Hazards model NIGERIA
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Research on individual motivation model of software engineering
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作者 SONG Yu WANG Ming 《通讯和计算机(中英文版)》 2009年第11期12-16,共5页
关键词 工程模型 软件项目 软件工程师 AMP CC模型 样式 字符 公证
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An Individual-Based Modeling Approach to Investigate Sympatric Speciation via Specialized Resource Usage
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作者 Maryam Karim Pour Sara Bandehbahman +1 位作者 Robin Gras Melania E. Cristescu 《Open Journal of Ecology》 2017年第3期222-269,共48页
An individual-based model, EcoSim, was employed to investigate if specialized resource use could promote sympatric speciation. Prey individuals in the original version of EcoSim were supplied with a single primary foo... An individual-based model, EcoSim, was employed to investigate if specialized resource use could promote sympatric speciation. Prey individuals in the original version of EcoSim were supplied with a single primary food resource. A dual resource version with different food resources (Food 1 and Food 2) was also developed to create favorable conditions for the emergence of specialized food consumption among prey individuals. The single resource version was used as the control to determine the impact of the presence of multiple food resources on the occurrence of sympatric speciation. Each unit of Food 2 contained a higher amount of energy than Food 1, and Food 1 was more accessible than Food 2. Initially, prey individuals mostly fed on Food 1. How-ever, after the emergence of food specialization, the consumption rate of Food 2 signifi-cantly exceeded the consumption rate of Food 1;although prey individuals more frequently encountered Food 1. While sympatric speciation was observed in the dual resource version runs, we could not identify any sympatric species in the single resource version runs. Machine learning techniques were also employed to identify the most influential initial conditions leading to sympatric speciation. According to the obtained results, in most lineages sympatric speciation occurred at the beginning of the food specialization pro-cess. When the lineage had a high special diversity, the lineage needed two different criteria to diverge sympatrically: possessing high genetic diversity and a large population size. In support of previous findings, this study demonstrated that the most accurate determination of initial conditions leading to sympatric speciation can be obtained from lineages that are at the beginning of the divergence process. In conclusion, this study indicated that divergent foraging behavior could potentially lead to the sympatric emergence of new species in the absence of geographic isolation. 展开更多
关键词 individual-BASED models Disruptive Selection DIVERGENT FEEDING Behavior modeling SYMPATRIC SPECIATION
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The Life-Cycle Model with Optimal Individual Years of Schooling and Simulation
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作者 Donghan Cai Huan Yang Zhongbin Chen 《数学计算(中英文版)》 2014年第2期44-48,共5页
关键词 生命周期模型 学校教育 年限 仿真 人力资本 数值模拟 分离式 增长率
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A basal area increment model for individual trees in mixed continuous cover forests in Iranian Caspian forests
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作者 Nishtman Hatami Peter Lohmander +1 位作者 Mohammad Hadi Moayeri Soleiman Mohammadi Limaei 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期99-106,共8页
The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran.Weanalyzed 421 core samples from 6 main species in the forest area to develop our ... The aim of this study was to develop and test a new basal area growth model in mixed species continuous cover forests in northern Iran.Weanalyzed 421 core samples from 6 main species in the forest area to develop our growth model.In each plot,we measured variables such as total tree height(m),diameter at breast height(DBH)(cm)and basal area of larger trees as cumulative basal areas of trees(GCUM)ofDBH[5 cm.The empirical data were analyzed using regression analysis.There was a statistically significant nonlinear function between the annual basal area increment,as the dependent variable,and the basal area of the individual trees and competition as explanatory variables.Reference area from the largest trees,was circular plot with area of 0.1 ha.GCUM was estimated for trees of DBH>5 cm.Furthermore,we investigated the dependencies of diameter growth of different species on stand density at different levels of competition,and diameter development of individual trees through time.The results indicate that competition caused by larger neighborhood trees has a negative effect on growth.In addition,the maximum diameter increment is affected by competition level.Therefore,the maximum diameter increment of species occurs when the trees are about 35–40 cm in dense-forest(40 to 0 m^2 per ha)and when the trees are about 60 to 70 cm in very dense forest(60 to 0 m^2 per ha)which is more likely to Caspian natural forests with high level density due to uneven-aged composition of stands. 展开更多
关键词 individual-tree model Iranian Caspian forests Continuous cover forestry Mixed stands Uneven-aged management
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从TVAAS到Individual Growth:美国田纳西州增值性教师评价发展新趋势 被引量:25
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作者 岳伟 陈俊源 +1 位作者 胡祥恩 莫伦 《现代教育管理》 CSSCI 北大核心 2019年第9期69-77,共9页
TVAAS是美国田纳西州创立的增值性教师评价方式,其核心特征是以学生成绩增幅衡量教师效能.TVAAS考虑到学生的原有基础与进步幅度,引导教师关注学生的成长状态.但是,TVAAS仍然存在分数价值导向、评价过程缺乏透明度以及无法为非测试型教... TVAAS是美国田纳西州创立的增值性教师评价方式,其核心特征是以学生成绩增幅衡量教师效能.TVAAS考虑到学生的原有基础与进步幅度,引导教师关注学生的成长状态.但是,TVAAS仍然存在分数价值导向、评价过程缺乏透明度以及无法为非测试型教师创造公正合理的成长分数等问题.学生成长档案袋评价是田纳西州增值性评价的新发展,它以学生作品为依据,以教师自评为基础,以同行评审为矫正,为非测试型教师提供了一个更为真实与个性化的评价经历.TVAAS与学生成长档案袋评价模式互为补充,使每位教师都能获得基于自身教学实际的个人增值(individual growth). 展开更多
关键词 增值性教师评价 TVAAS 学生成长档案袋评价 个人增值
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Epidemic spreading in scale-free networks including the effect of individual vigilance 被引量:2
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作者 Gong Yong-Wang Song Yu-Rong Jiang Guo-Ping 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期41-45,共5页
In this paper, we study the epidemic spreading in scale-flee networks and propose a new susceptible-infected- recovered (SIR) model that includes the effect of individual vigilance. In our model, the effective sprea... In this paper, we study the epidemic spreading in scale-flee networks and propose a new susceptible-infected- recovered (SIR) model that includes the effect of individual vigilance. In our model, the effective spreading rate is dynamically adjusted with the time evolution at the vigilance period. Using the mean-field theory, an analytical result is derived. It shows that individual vigilance has no effect on the epidemic threshold. The numerical simulations agree well with the analytical result. Purthermore, we investigate the effect of individual vigilance on the epidemic spreading speed. It is shown that individual vigilance can slow the epidemic spreading speed effectively and delay the arrival of peak epidemic infection. 展开更多
关键词 scale-free network susceptible-infected-recovered model individual vigilance epidemicthreshold
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Study on individualized information service for the reader in the library based on the network 被引量:1
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作者 唐振宇 李莘 +1 位作者 陈凤岩 冯玉强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第6期779-783,共5页
With the massive increase of digital resource based on the network,it becomes very important that how to help readers acquire the information needed according to the individualized requirement and interest in an accur... With the massive increase of digital resource based on the network,it becomes very important that how to help readers acquire the information needed according to the individualized requirement and interest in an accurate,convenient and prompt method. Therefore,it is very urgent to investigate individualized information service of library. In this paper,based on the development of the individualized information service for the reader in the college library,the individualized information service is clarified by using three perspectives,including establishment of individualized information demand model,integration of internal and external resource and protection of the reader privacy. Finally,the corresponding strategy and related measure are presented. 展开更多
关键词 individualized information service Demand model of the reader Resource integration Protection of the reader privacy
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Individual tree segmentation and biomass estimation based on UAV Digital aerial photograph
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作者 SUN Zhao WANG Yi-fu +6 位作者 DING Zhi-dan LIANG Rui-ting XIE Yun-hong LI Rui LI Hao-wei PAN Lei SUN Yu-jun 《Journal of Mountain Science》 SCIE CSCD 2023年第3期724-737,共14页
Digital aerial photograph(DAP)data is processed based on Structure from Motion(Sf M)algorithm and regional net adjustment method to generate digital surface discrete point clouds similar to Light Detection and Ranging... Digital aerial photograph(DAP)data is processed based on Structure from Motion(Sf M)algorithm and regional net adjustment method to generate digital surface discrete point clouds similar to Light Detection and Ranging(LiDAR)and digital orthophoto mosaic(DOM)similar to optical remote sensing image.In this study,we obtained highresolution images of mature forests of Chinese fir by unmanned aerial vehicle(UAV)flying through crossroute flight,and then reconstructed the threedimensional point clouds in the UAV aerial area by SfM technique.The point cloud segmentation(PCS)algorithm was used for the individual tree segmentation,and the F-score of the three sample plots were 0.91,0.94,and 0.94,respectively.Individual tree biomass modeling was conducted using 155 mature Chinese fir forests which were correctly segmented.The relative root mean squared error(rRMSE)values of random forest(RF),bagged tree(BT)and support vector regression(SVR)were 34.48%,35.74%and 40.93%,respectively.Our study demonstrated that DAP point clouds had great potential to extract forest vertical parameters and could be applied successfully in individual tree segmentation and individual tree biomass modeling. 展开更多
关键词 UAV images Structure from motion DAP point clouds individual tree segmentation individual tree biomass models
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