期刊文献+
共找到67,067篇文章
< 1 2 250 >
每页显示 20 50 100
Study on the Alignment Between Talent Training Directions and Employment Market Demands in the Landscape Architecture Industry
1
作者 Fengyi Xu Yang Su 《Journal of Contemporary Educational Research》 2024年第5期80-84,共5页
Currently,talent training in Chinese universities for landscape architecture is mainly divided into three directions:“landscape planning and design,”“landscape construction management,”and“landscape plant plantin... Currently,talent training in Chinese universities for landscape architecture is mainly divided into three directions:“landscape planning and design,”“landscape construction management,”and“landscape plant planting and maintenance.”However,with the background of the slowing urbanization process and the widespread demand for composite talents in society,it remains to be verified whether the traditional three major talent training directions in landscape architecture align with the job demands in the current construction market.Based on a survey and analysis of over 300 industry practitioners,this study found a clear trend of merging the three major employment directions into“landscape design and construction”and“landscape plant planting and maintenance.”This presents new requirements and directions for the skill training of landscape architecture majors in universities and provides insights into the alignment between talent training and employment demands in other industries. 展开更多
关键词 Landscape architecture profession Professional skills Employer demands Integration of industry and education
下载PDF
A Study on the Acceptance of the English Translation of Romance of the Three Kingdoms by Overseas Readers Based on Python Data Analysis Technology
2
作者 LIU Wei ZOU Jianling 《Sino-US English Teaching》 2023年第5期187-194,共8页
Paperless reading has become a prevalent trend among global readers,leading to the accumulation of vast amounts of reading data on numerous book websites.This offers new perspectives for studying translated works.This... Paperless reading has become a prevalent trend among global readers,leading to the accumulation of vast amounts of reading data on numerous book websites.This offers new perspectives for studying translated works.This paper utilizes Python-based data processing technology to collect and analyze reader reviews of Romance of the Three Kingdoms on Amazon and Goodreads,presenting trends in review volume,word cloud maps,and readers’emotional attitudes in a quantitative manner.The findings indicate that overseas readers generally exhibit a positive emotional tendency towards Romance of the Three Kingdoms and recognize its cultural value.However,negative opinions do exist,focusing on aspects of the book’s quality,such as printing quality and proofreading.These results provide valuable insights for the foreign translation of canonical texts. 展开更多
关键词 Romance of the Three Kingdoms readers’comment emotional analysis
下载PDF
Research on design methodology for railway freight service combination plans to meet diverse demands
3
作者 Yao Wang 《Railway Sciences》 2023年第4期525-538,共14页
Purpose–Facing the diverse needs of large-scale customers,based on available railway service resources and service capabilities,this paper aims to research the design method of railway freight service portfolio,selec... Purpose–Facing the diverse needs of large-scale customers,based on available railway service resources and service capabilities,this paper aims to research the design method of railway freight service portfolio,select optimal service solutions and provide customers with comprehensive and customized freight services.Design/methodology/approach–Based on the characteristics of railway freight services throughout the entire process,the service system is decomposed into independent units of service functions,and a railway freight service combination model is constructed with the goal of minimizing response time,service cost and service time.A model solving algorithm based on adaptive genetic algorithm is proposed.Findings–Using the computational model,an empirical analysis was conducted on the entire process freight service plan for starch sold from Xi’an to Chengdu as an example.The results showed that the proposed optimization model and algorithm can effectively guide the design of freight plans and provide technical support for real-time response to customers’diversified entire process freight service needs.Originality/value–With the continuous optimization and upgrading of railway freight source structure,customer demands are becoming increasingly diverse and personalized.Studying and designing a reasonable railway freight service plan throughout the entire process is of great significance for timely response to customer needs,improving service efficiency and reducing design costs. 展开更多
关键词 Diverse demands Service pattern Service quality Continuous clustering
下载PDF
Use of the “Veda-Lab Easy Reader+” for the Determination of T3, T4 and TSH Hormones in the Mountainous Population of Benin: Case of Natitingou
4
作者 Pamphile Thierry Houngbo Natacha Aivodji +1 位作者 Rodrigue Akotegnon Alphonse Sezan 《Advances in Bioscience and Biotechnology》 CAS 2024年第1期39-51,共13页
The thyroid, an endocrine gland located at the base of the neck, produces thyroid hormones (triiodothyronine (T3) and thyroxine (T4)). The production of these hormones is possible by iodine and other nutrients such as... The thyroid, an endocrine gland located at the base of the neck, produces thyroid hormones (triiodothyronine (T3) and thyroxine (T4)). The production of these hormones is possible by iodine and other nutrients such as selenium and certain vitamins. To assess the thyroid disturbances in the mountain population of Benin, a survey was conducted in Natitingou, a mountain town located in the department of Atacora, in the northwest of Benin, on a sample of thirty (30) adults (15 men and 15 women), most of whom are educated. The results of the questionnaire revealed that 43% of the surveyed population acknowledged having knowledge on the mentioned subject and have dietary habits based on the consumption of seafood, and also legumes (20%). The examination of the serum results of the dosage of T3, T4 and TSH hormones revealed cases of thyroid disturbances in the region (36.32% in men and 44.98% in women). The analysis of a comparative table including the “VEDALAB Easy Reader+” and five (05) other readers, presents the performance, reading techniques, principles, advantages and disadvantages of each device. Pending further studies, some recommendations were made at the end of this study to the academic authorities regarding probable cases of dysthyroidism for which additional examinations are required and an awareness for the improvement of dietary habits. 展开更多
关键词 Thyroid TSH T3 T4 “VEDALAB Easy reader+”
下载PDF
Research on Demand Response Potential of Adjustable Loads in Demand Response Scenarios
5
作者 Zhishuo Zhang Xinhui Du +3 位作者 Yaoke Shang Jingshu Zhang Wei Zhao Jia Su 《Energy Engineering》 EI 2024年第6期1577-1605,共29页
To address the issues of limited demand response data,low generalization of demand response potential evaluation,and poor demand response effect,the article proposes a demand response potential feature extraction and ... To address the issues of limited demand response data,low generalization of demand response potential evaluation,and poor demand response effect,the article proposes a demand response potential feature extraction and prediction model based on data mining and a demand response potential assessment model for adjustable loads in demand response scenarios based on subjective and objective weight analysis.Firstly,based on the demand response process and demand response behavior,obtain demand response characteristics that characterize the process and behavior.Secondly,establish a feature extraction and prediction model based on data mining,including similar day clustering,time series decomposition,redundancy processing,and data prediction.The predicted values of each demand response feature on the response day are obtained.Thirdly,the predicted data of various characteristics on the response day are used as demand response potential evaluation indicators to represent different demand response scenarios and adjustable loads,and a demand response potential evaluation model based on subjective and objective weight allocation is established to calculate the demand response potential of different adjustable loads in different demand response scenarios.Finally,the effectiveness of the method proposed in the article is verified through examples,providing a reference for load aggregators to formulate demand response schemes. 展开更多
关键词 demand response potential demand response scenarios data mining adjustable load evaluation system subjective and objective weight allocation
下载PDF
A Combination Prediction Model for Short Term Travel Demand of Urban Taxi
6
作者 Mingyuan Li Yuanli Gu +1 位作者 Qingqiao Geng Hongru Yu 《Computers, Materials & Continua》 SCIE EI 2024年第6期3877-3896,共20页
This study proposes a prediction model considering external weather and holiday factors to address the issue of accurately predicting urban taxi travel demand caused by complex data and numerous influencing factors.Th... This study proposes a prediction model considering external weather and holiday factors to address the issue of accurately predicting urban taxi travel demand caused by complex data and numerous influencing factors.The model integrates the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)and Convolutional Long Short Term Memory Neural Network(ConvLSTM)to predict short-term taxi travel demand.The CEEMDAN decomposition method effectively decomposes time series data into a set of modal components,capturing sequence characteristics at different time scales and frequencies.Based on the sample entropy value of components,secondary processing of more complex sequence components after decomposition is employed to reduce the cumulative prediction error of component sequences and improve prediction efficiency.On this basis,considering the correlation between the spatiotemporal trends of short-term taxi traffic,a ConvLSTM neural network model with Long Short Term Memory(LSTM)time series processing ability and Convolutional Neural Networks(CNN)spatial feature processing ability is constructed to predict the travel demand for urban taxis.The combined prediction model is tested on a taxi travel demand dataset in a certain area of Beijing.The results show that the CEEMDAN-ConvLSTM prediction model outperforms the LSTM,Autoregressive Integrated Moving Average model(ARIMA),CNN,and ConvLSTM benchmark models in terms of Symmetric Mean Absolute Percentage Error(SMAPE),Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and R2 metrics.Notably,the SMAPE metric exhibits a remarkable decline of 21.03%with the utilization of our proposed model.These results confirm that our study provides a highly accurate and valid model for taxi travel demand forecasting. 展开更多
关键词 Urban transport taxi travel demand prediction CEEMDAN-ConvLSTM modal components
下载PDF
Optimal dispatching strategy for residential demand response considering load participation
7
作者 Xiaoyu Zhou Xiaofeng Liu +2 位作者 Huai Liu Zhenya Ji Feng Li 《Global Energy Interconnection》 EI CSCD 2024年第1期38-47,共10页
To facilitate the coordinated and large-scale participation of residential flexible loads in demand response(DR),a load aggregator(LA)can integrate these loads for scheduling.In this study,a residential DR optimizatio... To facilitate the coordinated and large-scale participation of residential flexible loads in demand response(DR),a load aggregator(LA)can integrate these loads for scheduling.In this study,a residential DR optimization scheduling strategy was formulated considering the participation of flexible loads in DR.First,based on the operational characteristics of flexible loads such as electric vehicles,air conditioners,and dishwashers,their DR participation,the base to calculate the compensation price to users,was determined by considering these loads as virtual energy storage.It was quantified based on the state of virtual energy storage during each time slot.Second,flexible loads were clustered using the K-means algorithm,considering the typical operational and behavioral characteristics as the cluster centroid.Finally,the LA scheduling strategy was implemented by introducing a DR mechanism based on the directrix load.The simulation results demonstrate that the proposed DR approach can effectively reduce peak loads and fill valleys,thereby improving the load management performance. 展开更多
关键词 Residential demand response Flexible loads Load participation Load aggregator
下载PDF
Stochastic programming based coordinated expansion planning of generation,transmission,demand side resources,and energy storage considering the DC transmission system
8
作者 Liang Lu Mingkui Wei +4 位作者 Yuxuan Tao Qing Wang Yuxiao Yang Chuan He Haonan Zhang 《Global Energy Interconnection》 EI CSCD 2024年第1期25-37,共13页
With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage co... With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage coordinated expansion planning model based on stochastic programming was proposed to suppress the impact of wind and solar energy fluctuations.Multiple types of system components,including demand response service entities,converter stations,DC transmission systems,cascade hydropower stations,and other traditional components,have been extensively modeled.Moreover,energy storage systems are considered to improve the accommodation level of renewable energy and alleviate the influence of intermittence.Demand-response service entities from the load side are used to reduce and move the demand during peak load periods.The uncertainties in wind,solar energy,and loads were simulated using stochastic programming.Finally,the effectiveness of the proposed model is verified through numerical simulations. 展开更多
关键词 Hydro-wind-solar complementary Expansion planning demand response Energy storage system Source-network-demand-storage coordination
下载PDF
Optimal Bidding Strategies of Microgrid with Demand Side Management for Economic Emission Dispatch Incorporating Uncertainty and Outage of Renewable Energy Sources
9
作者 Mousumi Basu Chitralekha Jena +1 位作者 Baseem Khan Ahmed Ali 《Energy Engineering》 EI 2024年第4期849-867,共19页
In the restructured electricity market,microgrid(MG),with the incorporation of smart grid technologies,distributed energy resources(DERs),a pumped-storage-hydraulic(PSH)unit,and a demand response program(DRP),is a sma... In the restructured electricity market,microgrid(MG),with the incorporation of smart grid technologies,distributed energy resources(DERs),a pumped-storage-hydraulic(PSH)unit,and a demand response program(DRP),is a smarter and more reliable electricity provider.DER consists of gas turbines and renewable energy sources such as photovoltaic systems and wind turbines.Better bidding strategies,prepared by MG operators,decrease the electricity cost and emissions from upstream grid and conventional and renewable energy sources(RES).But it is inefficient due to the very high sporadic characteristics of RES and the very high outage rate.To solve these issues,this study suggests non-dominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ)for an optimal bidding strategy considering pumped hydroelectric energy storage and DRP based on outage conditions and uncertainties of renewable energy sources.The uncertainty related to solar and wind units is modeled using lognormal and Weibull probability distributions.TOU-based DRP is used,especially considering the time of outages along with the time of peak loads and prices,to enhance the reliability of MG and reduce costs and emissions. 展开更多
关键词 MICRO-GRID distributed energy resources demand response program UNCERTAINTY OUTAGE
下载PDF
A Novel Defender-Attacker-Defender Model for Resilient Distributed Generator Planning with Network Reconfiguration and Demand Response
10
作者 Wenlu Ji Teng Tu Nan Ma 《Energy Engineering》 EI 2024年第5期1223-1243,共21页
To improve the resilience of a distribution system against extreme weather,a fuel-based distributed generator(DG)allocation model is proposed in this study.In this model,the DGs are placed at the planning stage.When a... To improve the resilience of a distribution system against extreme weather,a fuel-based distributed generator(DG)allocation model is proposed in this study.In this model,the DGs are placed at the planning stage.When an extreme event occurs,the controllable generators form temporary microgrids(MGs)to restore the load maximally.Simultaneously,a demand response program(DRP)mitigates the imbalance between the power supply and demand during extreme events.To cope with the fault uncertainty,a robust optimization(RO)method is applied to reduce the long-term investment and short-term operation costs.The optimization is formulated as a tri-level defenderattacker-defender(DAD)framework.At the first level,decision-makers work out the DG allocation scheme;at the second level,the attacker finds the optimal attack strategy with maximum damage;and at the third level,restoration measures,namely distribution network reconfiguration(DNR)and demand response are performed.The problem is solved by the nested column and constraint generation(NC&CG)method and the model is validated using an IEEE 33-node system.Case studies validate the effectiveness and superiority of the proposed model according to the enhanced resilience and reduced cost. 展开更多
关键词 Distribution system RESILIENCE defender-attacker-defender distributed generator demand response microgrids formation
下载PDF
A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
11
作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) INVENTORY Time-Proportional Deterioration Two-Phased demand
下载PDF
Fuzzy Inventory Model under Selling Price Dependent Demand and Variable Deterioration with Fully Backlogged Shortages
12
作者 Tanzim S. Shaikh Santosh P. Gite 《American Journal of Operations Research》 2024年第2期87-103,共17页
The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. Shortages are allowed and fu... The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. Shortages are allowed and fully backlogged. Fuzzy optimal solution is obtained by considering hexagonal fuzzy numbers and for defuzzification Graded Mean Integration Representation Method. A numerical example is provided for the illustration of crisp and fuzzy, both models. To observe the effect of changes in parameters, sensitivity analysis is carried out. 展开更多
关键词 DETERIORATION Selling Price Dependent demand Fully Backlogged Hexagonal Fuzzy Numbers Graded Mean Integration Representation Method
下载PDF
Demand and Analysis of Clinical Research Curriculum in Medical Universities
13
作者 Jingxuan Liu Li Wang 《Journal of Clinical and Nursing Research》 2024年第7期296-302,共7页
Objective:To investigate the needs of medical students regarding clinical research curricula to provide scientifically sound offerings and cultivate their clinical research thinking.Methods:From June to October 2022,m... Objective:To investigate the needs of medical students regarding clinical research curricula to provide scientifically sound offerings and cultivate their clinical research thinking.Methods:From June to October 2022,medical students at medical universities in Shaanxi Province were surveyed using online questionnaires.The survey covered their demographic information,awareness of their major,understanding of clinical research,and preferences for curriculum content.Results:A total of 341 valid questionnaires were analyzed.Medical students demonstrated a strong awareness of their majors but a relatively low awareness of clinical research.There was significant demand for clinical research courses,with preferences for professionally oriented(81.8%),market-oriented(100%),theoretically and practically integrated teaching(78.6%),and application-focused(73.0%)courses.Conclusion:Medical colleges and universities should align clinical research curricula with the actual needs of medical students and clinical practice.Reforms in curriculum design and teaching methods are essential to better prepare students for careers in public health. 展开更多
关键词 Medical college Clinical research CURRICULUM demand ANALYSIS
下载PDF
Survey on the Demand for Elderly Care Services of Community Residents in Beijing and Analysis of Influencing Factors
14
作者 Yue Zhai Xianguo Bi +3 位作者 Weimin Liu Hong Wang Xinxin Zhang Jing Chen 《Journal of Clinical and Nursing Research》 2024年第4期79-87,共9页
Objective: To investigate the current situation of the demand for geriatric care services of community residents in Beijing and analyze the influencing factors to provide a reference basis for meeting the demand for d... Objective: To investigate the current situation of the demand for geriatric care services of community residents in Beijing and analyze the influencing factors to provide a reference basis for meeting the demand for diversified and professional geriatric care services. Methods: A self-made questionnaire was used to randomly survey 1558 elderly individuals at community health service centers in 8 urban districts where elderly care centers were planned to be built. The influencing factors of the different characteristics of elderly care service needs from three aspects were analyzed using a dichotomous logistic regression model: predisposing, enabling, and, need factors. Results: 69.7% of the elderly required home care services, 22.8% wanted to get care services at elderly care centers, 15.9% wanted to get care services at nursing homes, 12.3% required community care services, and 7.4% didn’t know where to access care services. 68.5% of the elderly required care services for disabilities/semi-disabilities, 58.0% for dementia, 54.7% for common diseases, 34.9% for rehabilitation training, 33.0% for plumbing care, and 7.5% for hospice care. At the same time, there were urban- rural differences in the demand for elderly care services, with suburban elderly having a higher demand for care services than those living in urban areas (P < 0.05). The elderly’s demand for care services was mainly related to age, place of residence, and gender in the causative factors, mode of residence and physical condition among able factors, and mode of care services and care needs among need factors (P < 0.05). Conclusion: The demand for elderly care services was differentiated by factors including place of residence, age, and gender. It is crucial to accurately match the demand for elderly care services, innovate the mode of elderly care services, and improve the service quality to improve the elderly health service system. 展开更多
关键词 Elderly care Service system demand Population ageing Influencing factors
下载PDF
Research on Adaptability Analysis of Environmental Space Demand and Design Optimization of Daycare Centers: Taking Chongqing’s Community F as an Example
15
作者 Tijin Gui Minna Yu +1 位作者 Bin Chen Jun Tao 《Journal of World Architecture》 2024年第3期49-56,共8页
Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to de... Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to demand”as a central aspect.It examines indoor and outdoor environmental space needs at a micro level,considering both functional requirements and spiritual needs based on existing research.The analysis incorporates three adaptive elements:current construction,surrounding environment,and operational management.It explores the feasibility of restructuring spatial layouts,utilizing local resources,and integrating Bayu cultural characteristics.Finally,through design optimization practices,the study proposes three strategies for aging optimization:functional integration and interaction,user-friendly facilities,and emotional connections to place. 展开更多
关键词 Daycare center Environmental space Willingness to demand Design optimization
下载PDF
Link Demands对.NET Framework分布式系统安全性的影响
16
作者 杜树杰 林晓彤 刘士才 《计算机工程与应用》 CSCD 北大核心 2004年第8期143-147,共5页
客观地讲,.NET安全体系是采用全新的模式建立的,更多地考虑了基于.NET的应用系统在安全性和执行效率上的统一,这一点是可以理解的。它提出了基于WEB的分布式应用系统在安全核心技术上新的设计思想。影响.NETFramework应用系统安全性的... 客观地讲,.NET安全体系是采用全新的模式建立的,更多地考虑了基于.NET的应用系统在安全性和执行效率上的统一,这一点是可以理解的。它提出了基于WEB的分布式应用系统在安全核心技术上新的设计思想。影响.NETFramework应用系统安全性的因素有很多,其中由链接请求(Linkdemands)引起的影响系统安全性的潜在错误相当多。文章分析了Linkdemands可能带来的系统安全性隐患,并就此提出了一些建议。 展开更多
关键词 链接请求 .NET Framework JIT 堆栈遍历 CLR 中间语言
下载PDF
Ductility demands on buckling-restrained braced frames under earthquake loading 被引量:11
17
作者 Larry A.Fahnestock Richard Sause +1 位作者 James M.Ricles Le-Wu Lu 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期255-268,共14页
Accurate estimates of ductility demands on buckling-restrained braced frames(BRBFs)are crucial to performance-based design of BRBFs.An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS ... Accurate estimates of ductility demands on buckling-restrained braced frames(BRBFs)are crucial to performance-based design of BRBFs.An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS Center,Lehigh University to prepare for an upcoming experimental program.The analysis program DRAIN-2DX was used to model a one-bay,four-story prototype BRBF including material and geometric nonlinearities.The buckling- restrained brace(BRB)model incorporates both isotropic and kinematic hardening.Nonlinear static pushover and time- history analyses were performed on the prototype BRBF.Performance objectives for the BRBs were defined and used to evaluate the time-history analysis results.Particular emphasis was placed on global ductility demands and ductility demands on the BRBs.These demands were compared with anticipated ductility capacities.The analysis results,along with results from similar previous studies,are used to evaluate the BRBF design provisions that have been recommended for codification in the United States.The results show that BRB maximum ductility demands can be as high as 20 to 25.These demands significantly exceed those anticipated by the BRBF recommended provisions.Results from the static pushover and time- history analyses are used to demonstrate why the ductility demands exceed those anticipated by the recommended provisions. The BRB qualification testing protocol contained in the BRBF recommended provisions is shown to be inadequate because it requires only a maximum ductility demand of at most 7.5.Modifications to the testing protocol are recommended. 展开更多
关键词 BUILDINGS buckling-restrained braced frames buckling-restrained braces structural response seismic response ductility demand seismic codes and standards
下载PDF
Time-variant fragility analysis of the bridge system considering time-varying dependence among typical component seismic demands 被引量:4
18
作者 Song Shuai Qian Yongjiu +2 位作者 Liu Jing Xie Xiaorui Wu Gang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第2期363-377,共15页
This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Bas... This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Based on material deterioration mechanisms and incremental dynamic analysis, the time-evolving seismic demands of components were obtained in the form of marginal probability distributions. The time-varying dependences among bridge components were then captured with the best fitting copula function, which was selected from the commonly used copula classes by the empirical distribution based analysis method. The system time-variant fragility curves at different damage states were developed and the effects of time-varying dependences among components on the bridge system fragility were investigated. The results indicate the time-varying dependence among components significantly affects the time-variant fragility of the bridge system. The copula technique captures the nonlinear dependence among component seismic demands accurately and easily by separating the marginal distributions and the dependence among them. 展开更多
关键词 system FRAGILITY CHLORIDE corrosion TIME-VARYING DEPENDENCE COPULA function probabilistic seismic demand
下载PDF
Investigation of Direct Causes of Drug Relapse and Abstainers’ Demands in a Compulsive Detoxification Center in Wuhan City of China 被引量:3
19
作者 ZENG-ZHEN WANG QING WANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第5期404-409,共6页
Objective To identify the direct causes of drug relapse and abstainers’ demand, and to develop programs for the prevention of drug relapse. Methods Abstainers in a Compulsive Detoxification Center in Wuhan City, capi... Objective To identify the direct causes of drug relapse and abstainers’ demand, and to develop programs for the prevention of drug relapse. Methods Abstainers in a Compulsive Detoxification Center in Wuhan City, capital of Hubei Province were randomly selected. An investigation on the direct causes of drug relapse and abstainers’ demands was conducted with multiple-choice questionnaires and face to face interviews. Data were analyzed with SPSS 12.0. Results The direct causes leading to drug relapse included: temptation to use drug again by themselves or by their drug mates, seeking pleasure and ecstasy from drug use, relatively well off living, mental stress, irritation, demoralization, family conflicts, unemployment, feeling distrusted by the family, lack of care and love from the family, and discrimination by others. abstainers’ demands after detoxification and returning to the society included: care and support from the family, employment assistance, changing living environment, understanding by others, support from the society, and keeping far away from drugs. Conclusions Environmental factors are the direct causes of drug relapse, and negative irritation is its predisposing causes. Leaving former residence, more care and help given by both the family and the society and raising their overall quality of life are the demands of abstainers. 展开更多
关键词 Drug abuse Causes of drug relapse demands
下载PDF
An improved modal pushover analysis procedure for estimating seismic demands of structures 被引量:5
20
作者 毛建猛 翟长海 谢礼立 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第1期25-31,共7页
The pushover analysis (POA) procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis (MPA) procedur... The pushover analysis (POA) procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis (MPA) procedure was proposed by Chopra et al. (2001). However, invariable lateral force distributions are still adopted in the MPA. In this paper, an improved MPA procedure is presented to estimate the seismic demands of structures, considering the redistribution of inertia forces after the structure yields. This improved procedure is verified with numerical examples of 5-, 9- and 22-story buildings. It is concluded that the improved MPA procedure is more accurate than either the POA procedure or MPA procedure. In addition, the proposed procedure avoids a large computational effort by adopting a two-phase lateral force distribution.. 展开更多
关键词 seismic demand estimation pushover analysis improved modal pushover analysis two-phase lateral forcedistribution capacity curve
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部