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611.
A continuous-time stochastic model is constructed to analyze how to control rent seeking behaviors. Using the stochastic optimization methods based on the modem risky theory, a unique positive solution to the dynamic model is derived. The effects of preference-related parameters on the optimal control level of rent seeking are discussed, and some policy measures are given. The results show that there exists a unique solution to the stochastic dynamic model under some macroeconomic assumptions, and that raising public expenditure may have reverse effects on rent seeking in an underdeveloped or developed economic environment. 相似文献
612.
我国高等院校核心竞争力结构解析 总被引:1,自引:0,他引:1
金红 《南通航运职业技术学院学报》2008,7(2):99-103
随着我国高等教育市场改革进程的加快,我国高等院校之间的竞争将日趋激烈,从而催生了我国高校核心竞争力培育战略的大力实施。有效地进行核心竞争力结构体系解析是高等院校实施核心竞争力培育战略的基础性前提。验证性因子分析可以为结构体系的有效性和现实性提供实证检验。 相似文献
613.
素数模19的同余方程的整数解 总被引:1,自引:0,他引:1
邹兆南 《重庆交通大学学报(自然科学版)》2008,27(3):491-492
证明了连续正整数偶次幂之和,关于素数模19同余方程的若干性质,并给出了全部整数解。 相似文献
614.
结合规范及相关资料推导出桩基础在横向荷载作用下的挠曲微分方程并给出计算桩基础位移及内力的计算公式.公式的形式简单,方便用于桥梁桩基础计算. 相似文献
615.
616.
Jiang et al. (Jiang, Y.Q., Wong, S.C., Ho, H.W., Zhang, P., Liu, R.X., Sumalee, A., 2011. A dynamic traffic assignment model for a continuum transportation system. Transportation Research Part B 45 (2), 343–363) proposed a predictive continuum dynamic user-optimaDUO-l to investigate the dynamic characteristics of traffic flow and the corresponding route-choice behavior of travelers. Their modeled region is a dense urban city that is arbitrary in shape and has a single central business district (CBD). However, we argue that the model is not well posed due to an inconsistency in the route-choice strategy under certain conditions. To overcome this inconsistency, we revisit the PDUO-C problem, and construct an improved path-choice strategy. The improved model consists of a conservation law to govern the density, in which the flow direction is determined by the improved path-choice strategy, and a Hamilton–Jacobi equation to compute the total travel cost. The simultaneous satisfaction of both equations can be treated as a fixed-point problem. A self-adaptive method of successive averages (MSA) is proposed to solve this fixed-point problem. This method can automatically determine the optimal MSA step size using the least squares approach. Numerical examples are used to demonstrate the effectiveness of the model and the solution algorithm. 相似文献
617.
ABSTRACTSustainability has become an important issue in container terminal operations. However, relatively little research has been conducted to assess its association with sustainable supply chain management (SSCM). In this study, SSCM consists of internal sustainability practices and external sustainability collaboration. We empirically examined the effects of internal sustainability practices and external sustainability collaboration on sustainability performance in container terminal operations at the Port of Kaohsiung in Taiwan. We developed a model adopting the SSCM construct, which consisted of two dimensions: internal sustainability practices and external sustainability collaboration. Several research hypotheses were formulated from the theory and the hypotheses were tested using survey data collected from 141 employees who worked with container terminals. We found that internal sustainability practices and external sustainability collaboration positively affected sustainability performance, whereas external sustainability collaboration had a positive influence on internal sustainability practices. There is a discussion of the implications of these findings for developing sustainability and improving sustainability performance in container terminals and ports. 相似文献
618.
In this paper, we investigate the boundedness character, the global attractivity and the periodic nature of the svstem of ratiol difference equatious:xn+1=p+yn-k/xn,yn+1=q+xn-k/yn,n=0,1,2..., where p>0, q>0, k∈ of the system of rational difference equations:xn+1=P+yn-k/xn, yn=q+xn-k/yn,n=0,1,2 {1,2,…} and the initial values x1, y1∈(0,∞), i=- k, -k+1,… 0. Some new results are obtained. 相似文献
619.
根据交通流系统所具有的物理量对时间的全导数的积分公式,即系统内物理量对时间的全导数等于控制域内该物理量对时间的偏导数与单位时间经过控制线的该物理量的通量之和,结合质点系动量定理,建立了积分形式的交通流动量方程,即系统内的交通流动量对时间的导数等于作用在系统上的外力的矢量和,计算了控制域内动量随时间的变化率,以此判断其交通状况。 相似文献
620.
Wireless ICTs are often used in public transport. Using survey data collected amongst 98 train travellers this article aims
to gain insight into important factors that affect train travellers’ intentions to communicate with distant others while travelling.
More specifically, the focus is on the decision-making process that leads to the intention to choose for a confidential conversation
either via ‘audible’ mobile phone or via ‘silent’ SMS/e-mail. An approach that is related to the Extended Model of Goal-directed
Behaviour (EMGB) is applied. Structural equation modelling results indicate that in particular past SMS behaviour, the desire
to communicate (goal desire), the perceived efficacy and controllability influence the intention to conduct a confidential
phone conversation in the train. The influence of the social environment (e.g. eavesdropping) seems to be less important.
Several EMGB constructs are strongly influenced by age. It seems that older respondents have more negative attitudes towards
telephoning while travelling by train, and find it more difficult to call other people in such a situation. Finally, they
have a lower intention than younger respondents to conduct a confidential conversation over the phone while travelling.
相似文献
Martin DijstEmail: |