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Time varying congestion pricing for multi-class and multi-mode transportation system with asymmetric cost functions
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作者 钟绍鹏 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期77-82,共6页
This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combin... This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combined applications of the space-time expanded network(STEN) and the conventional network equilibrium modeling techniques,a multi-class,multi-mode and multi-criteria traffic network equilibrium model is developed.Travelers of different classes have distinctive value of times(VOTs),and travelers from the same class perceive their travel disutility or generalized costs on a route according to different weights of travel time and travel costs.Moreover,the symmetric cost function model is extended to deal with the interactions between buses and private cars.It is found that there exists a uniform(anonymous) link toll pattern which can drive a multi-class,multi-mode and multi-criteria user equilibrium flow pattern to a system optimum when the system's objective function is measured in terms of money.It is also found that the marginal cost pricing models with a symmetric travel cost function do not reflect the interactions between traffic flows of different road sections,and the obtained congestion pricing toll is smaller than the real value. 展开更多
关键词 time varying congestion pricing ASYMMETRIC MULTI-CLASS MULTI-MODE MULTI-CRITERIA
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A simplified approach for negative skin friction calculation of special-shaped pile considering pile-soil interaction under surcharge 被引量:3
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作者 孔纲强 周航 +2 位作者 刘汉龙 丁选明 LIANG Robert 《Journal of Central South University》 SCIE EI CAS 2014年第9期3648-3655,共8页
A simplified approach was proposed to analyze the negative skin friction calculation of special-shaped pile considering pile-soil interaction under surcharge. Based on the concentric cylinder shearing theory, consider... A simplified approach was proposed to analyze the negative skin friction calculation of special-shaped pile considering pile-soil interaction under surcharge. Based on the concentric cylinder shearing theory, considering the changes of pile shape(such as, taper angle and diameters of pile base, etc.), the load-transfer of special-shaped pile was built. The accuracy of the developed simplified approach was verified by numerical simulation model with the same condition. Then, the influence factors, such as, taper angles, the diameter of pile base, surcharge, and pile-soil interface parameters were analyzed and discussed. The results show that the developed simplified approach can calculate NSF of special-shaped pile under surcharge effectively. A limited parametric study indicates that in many practical situations special-shaped piles(such as belled wedge pile shown in this work) offer a design option that is more economical than traditional uniform cross-section piles. 展开更多
关键词 negative skin friction special-shaped pile pile-soil interaction dragload downdrag SURCHARGE
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A multi-objective model for cordon-based congestion pricing schemes with nonlinear distance tolls 被引量:1
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作者 孙鑫 刘志远 +3 位作者 THOMPSON Russell G 别一鸣 翁金贤 陈淑燕 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1273-1282,共10页
Congestion pricing is an important component of urban intelligent transport system.The efficiency,equity and the environmental impacts associated with road pricing schemes are key issues that should be considered befo... Congestion pricing is an important component of urban intelligent transport system.The efficiency,equity and the environmental impacts associated with road pricing schemes are key issues that should be considered before such schemes are implemented.This paper focuses on the cordon-based pricing with distance tolls,where the tolls are determined by a nonlinear function of a vehicles' travel distance within a cordon,termed as toll charge function.The optimal tolls can give rise to:1) higher total social benefits,2) better levels of equity,and 3) reduced environmental impacts(e.g.,less emission).Firstly,a deterministic equilibrium(DUE) model with elastic demand is presented to evaluate any given toll charge function.The distance tolls are non-additive,thus a modified path-based gradient projection algorithm is developed to solve the DUE model.Then,to quantitatively measure the equity level of each toll charge function,the Gini coefficient is adopted to measure the equity level of the flows in the entire transport network based on equilibrium flows.The total emission level is used to reflect the impacts of distance tolls on the environment.With these two indexes/measurements for the efficiency,equity and environmental issues as well as the DUE model,a multi-objective bi-level programming model is then developed to determine optimal distance tolls.The multi-objective model is converted to a single level model using the goal programming.A genetic algorithm(GA) is adopted to determine solutions.Finally,a numerical example is presented to verify the methodology. 展开更多
关键词 distance-based toll charging schemes EQUITY path-based gradient projection algorithm non-additive goal programming
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The Impact of Automation in Service Industries" An Empirical Study
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作者 M. Eva Diz-Comesana Nuria Rodriguez-Lopez 《Chinese Business Review》 2014年第3期162-178,共17页
Academic research into service industries has explored the characteristics of interpersonal interactions between employees and customers, but there are few studies addressing the issues of consumer interaction with te... Academic research into service industries has explored the characteristics of interpersonal interactions between employees and customers, but there are few studies addressing the issues of consumer interaction with technology and its influence on the objectives and results of the operations subsystem. This study examines the elements of the service encounter, and the changes automation originates in them and their relationships. The paper also examines changes in the elements and results of the operations subsystem, as a result of automation. We propose that the customer's relationship with employees and/or technology and automated systems for the service impact the objectives and results of the operations subsystem, all of which could have an effect on the company's competitive position. The empirical study is focused on four industries, namely, toll motorways, car parks, carwash and video/DVD rental companies, in an attempt to identify objectives that lead companies to implement automated processes affecting the customer's relationship with the company. The hypotheses generated are contrasted with a structural equation modelling. The results confirm that the customer's relationship with employees and automated systems for the service impacts the objectives and results of the operations subsystem. Also, the results show how automation can enable firms simultaneously to achieve acceptable levels of flexibility and productivity, two dimensions that have traditionally been considered opposites. 展开更多
关键词 service encounter AUTOMATION technology operations subsystem objectives elements of service delivery COST time reduction FLEXIBILITY
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Bilevel linear programming model of charging for effluent based on price control
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作者 李煜华 李磊 +1 位作者 胡运权 邵海宏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期292-296,共5页
For the optimum price problem of charging for effluent, this paper analyzes the optimal Pigovian Tax and the serious information asymmetry problem existing in the application process of optimal Pigovian Tax, which is ... For the optimum price problem of charging for effluent, this paper analyzes the optimal Pigovian Tax and the serious information asymmetry problem existing in the application process of optimal Pigovian Tax, which is predominant in theory. Then the bilevel system optimizing decision-making theory is applied to give bilevel linear programming decision-making model of charging for effluent, in which the government (environmental protection agency) acts as the upper level decision-making unit and the polluting enterprises act as the lower level decision-making unit. To some extent, the model avoids the serious information asymmetry between the government and the polluting enterprises on charging for effluent. 展开更多
关键词 charging for effluent Pigovian Tax price control bilevel linear programming information asymmetry
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Establishment of Model Home Garden for Home Consumption and Income Generation of Poor and HIV Victim Women at Bahir Dar, Ethiopia
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作者 Habtamu Tegen Yazie Chanie Minuyelet Jembere 《Journal of Agricultural Science and Technology(A)》 2015年第3期183-189,共7页
For resource poor and HIV victim urban and pre-urban dwellers in developing countries, home garden is vital to enhance food and nutrient security. The availability of both ground and surface water in Bahir Dar city of... For resource poor and HIV victim urban and pre-urban dwellers in developing countries, home garden is vital to enhance food and nutrient security. The availability of both ground and surface water in Bahir Dar city of Ethiopia propels many poor families to produce vegetable and fruit crop for home consumption and income generation. Productivity of fruits and vegetables has been seriously affected due to lack of high yield with good quality varieties, poor knowledge of agronomic practices, poor water and fertilizer managements to exploit the full potential benefits of home garden to the area. To minimize those gaps, resource poor and HIV victim women headed households were selected and model home garden were established to demonstrate improved production practices. Subsequent trainings and experience sharing focused on the different techniques of vegetable and fruit crops production and management, methods of compost preparation and how to generate income from home garden were provided. The seeds of lettuce, Swiss chard, head cabbage, kale, carrot and improved banana sucker and coffee seedlings were supplied for each model home garden. Based on the training and experiences gained, different vegetable growing structures, such as old plastic containers, wooden boxes, vegetable growing shelves made from locally available materials and old used car tier, and "food always in the house" (FAITH) gardening techniques were established to maximize the potential of home garden both vertically and horizontally. Within one growing season, participants produced plenty leafy vegetable for home consumption and they started to generate income by supplying fresh vegetable products to the local market. Nowadays, participants have been sharing their knowledge and experiences to new neighboring gardeners through their model home gardens. Therefore, the respective stakeholders should provide continuous technical and financial support to strengthen the established model home garden as a training center to disseminate improved production techniques for Bahir Dar city residents for the future. 展开更多
关键词 Home garden VEGETABLES FRUITS women.
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Contributions of qqqq Components to Axial Charges of Proton and N(1440)
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作者 袁思刚 安春生 何军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期697-700,共4页
The axial charges of the proton and N(1440) are studied in the framework of an extended constituent quark model (CQM) including qqqqq components. The cancellation between the contributions of qqq components and qq... The axial charges of the proton and N(1440) are studied in the framework of an extended constituent quark model (CQM) including qqqqq components. The cancellation between the contributions of qqq components and qqqqq components gives a natural explanation to the experimental value of the proton axial charge, which can not be well reproduced in the traditional CQM even after the SU(6) × O(3) symmetry breaking is taken into account. The experimental value of axial charge pins down the proportion of the qqqqq component in the proton to about 20%, which is consistent with the ones given by the strong decay widths and helicity amplitudes. Besides, an axial charge for N(1440) about 1 is predicted with 30% qqqqq component, which is obtained by the strong and electromagnetic decays. 展开更多
关键词 axial charge five-quark component PROTON
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Study on urban housing consumption selection based on Logit model
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作者 Zhaoyun Li 《International English Education Research》 2015年第8期62-64,共3页
Housing problem is the problem of livelihood. The problem of housing consumer behavior has become one of the main concern of the Government after more than 10 years the rapid development of real estate. This article i... Housing problem is the problem of livelihood. The problem of housing consumer behavior has become one of the main concern of the Government after more than 10 years the rapid development of real estate. This article is based on the logit model, integrated family net worth, family income, labor factors and so on. Results showed that housing in Shanghai have household net worth is the most critical, followed by labour income and labour force. 展开更多
关键词 housing consumption logit model
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创优质服务“梨温品牌”
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作者 胡禾根 吴建刚 《当代江西》 2008年第8期33-33,共1页
梨温高速公路东起玉山县梨园,与浙江省杭金衢高速公路相接,西止进贤县温家圳,与温厚、乐温高速公路相连,全长245公里。它是江西与长三角接轨的富民路,是沟通东部地区与中部地区的连心桥,是支撑我省崛起的大动脉。
关键词 温家圳 乐温高速公路 富民路 路政执法 杭金衢高速 行车环境 养护管理 计重收费 收费 收费模
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Classification of Quasifinite Modules with Nonzero Central Charges for EALAs of Type A with Coordinates in Quantum Torus
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作者 Rencai LV 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第2期129-138,共10页
The author first constructs a Lie algebra ∑ :=∑(q, Wd) from rank 3 quantum torus, which is isomorphic to the core of EALAs of type Ad-1 with coordinates in quantum torus Cqd, and then gives the necessary and suff... The author first constructs a Lie algebra ∑ :=∑(q, Wd) from rank 3 quantum torus, which is isomorphic to the core of EALAs of type Ad-1 with coordinates in quantum torus Cqd, and then gives the necessary and sufficient conditions for the highest weight modules to be quasifinite nonzero central charges are Finally the irreducible Z-graded quasifinite ∑-modules with classified. 展开更多
关键词 Core of EALAs Graded modules Quasifinite module Highest weightmodule Quantum torus
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Effects of Surface Dipole Lengths on Evaporation of Tiny Water Aggregation
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作者 王棽 涂育松 +1 位作者 万荣正 方海平 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第5期623-628,共6页
Using molecular dynamics simulation, we compared evaporation behavior of a tiny amount of water molecules adsorbed on solid surfaces with different dipole lengths, including surface dipole lengths of 1 fold, 2 folds, ... Using molecular dynamics simulation, we compared evaporation behavior of a tiny amount of water molecules adsorbed on solid surfaces with different dipole lengths, including surface dipole lengths of 1 fold, 2 folds, 4 folds, 6 folds and 8 folds of 0.14 nm and different charges from 0.1e to 0.9e. Surfaces with short dipole lengths (1-fold system) can always maintain hydrophobic character and the evaporation speeds are not influenced, whether the surface charges are enhanced or weakened; but when surface dipole lengths get to 8 folds, surfaces become more hydrophilic as the surface charge increases, and the evaporation speeds increase gradually and monotonically. By tuning dipole lengths from 1-fold to 8-fold systems, we confirmed non-monotonic variation of the evaporation flux (first increases, then decreases) in 4 fold system with charges (0.1e-0.7e), reported in our previous paper [S. Wang, et al., J. Phys. Chem. B 116 (2012) 13863], and also show the process from the enhancement of this unexpected non-monotonic variation to its vanishment with surface dipole lengths increasing. Herein, we demonstrated two key factors to influence the evaporation flux of a tiny amount of water molecules adsorbed on solid surfaces: the exposed surficial area of water aggregation from where the water molecules can evaporate directly and the attraction potential from the substrate hindering the evaporation. In addition, more interestingly, we showed extra steric effect of surface dipoles on further increase of evaporation flux for 2-folds, 4-folds, 6-folds and 8-folds systems with charges around larger than 0.7e. (The steric effect is first reported by parts of our authors [C. Wang, et al., Sci. Rep. 2 (2012) 358]). This study presents a complete physical picture of the influence of surface dipole lengths on the evaporation behavior of the adsorbed tiny amount of water. 展开更多
关键词 EVAPORATION surficial water WETTABILITY dipole length molecular dynamics
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