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981.
In this paper, the problems of combustion instability and high-temperature corrosion of pulverized coal fired boiler are investigated by numerical simulation and analysis of the momentum moment. Elbow and twisting plate type of burners are used in the boiler, and the reverse moment of momentum is formed at the outlet of the fuel-rich side of the burner. The momentum moment in the boiler is opposite to the designed tangential circle, and the tangential circle in the boiler is reversed rotation. The reverse moment of momentum at the burner outlet can be eliminated by using louver horizontal bias pulverized coal burner, while the problems of combustion instability and high-temperature corrosion of the boiler are solved, and the combustion efficiency is improved. Accordingly,economic benefit is obviously got. 相似文献
982.
The relationship between financial system, law framework or economic growth has attracted considerable attention for years. However, there are some questions still remaining unanswered: between tangible assets protection and intellectual property protection, which is more important? Between external financing and property rights protection, which does play a greater role for the economic development? According to the dynamic stochastic general equilibrium(DSGE) model with non-free market factors, we study the effectiveness of property protection and external financing, and try to answer these questions. The model fits the data well, and we find:(1) protection of intellectual property plays a more important role than that of tangible asset, in the promotion of economy;(2) relaxation of financial constraints on corporate is more effective in the short run, while the protection of intellectual property is more effectual in the long term. 相似文献
983.
It is a rather challenging project to seek the amount of funds raised by funds-raising companies. This paper is focused on China private equity funds that have succeeded in raising their funds. The grey systemic model is applied in the research and a formula is established for the law of fund-raising of the private equity funds in order to sum up the capacity of China private equity investment funds and to establish a model accordingly. 相似文献
984.
The dispute settlement mechanism (DSM) has long been the focus of attention because of its significant role in the institutional construction of China’s free trade agreements (FTAs). Thus, this paper is to make an analysis of the DSMs of China’s established FTAs from a legal perspective of international regime study, which leads to the finding of a co-existence mode of formal and informal DSMs in China’s FTAs. This paper also discusses the motivation and significance of such a choice. 相似文献
985.
It has been over fifteen years since the Morgantown PRT system went into passenger service. Its start was marked by cost overruns, high operating costs and poor reliability. However over time, these initial problems and difficulties have been overcome, and today the system provides an extremely important and reliable service that links downtown Morgantown with three campuses of West Virginia University. It is still running. This paper provides background on the development of the system and current operating characteristics of this famous transit demonstration project. 相似文献
986.
A review on travel behaviour modelling in dynamic traffic simulation models for evacuations 总被引:1,自引:0,他引:1
Dynamic traffic simulation models are frequently used to support decisions when planning an evacuation. This contribution
reviews the different (mathematical) model formulations underlying these traffic simulation models used in evacuation studies
and the behavioural assumptions that are made. The appropriateness of these behavioural assumptions is elaborated on in light
of the current consensus on evacuation travel behaviour, based on the view from the social sciences as well as empirical studies
on evacuation behaviour. The focus lies on how travellers’ decisions are predicted through simulation regarding the choice
to evacuate, departure time choice, destination choice, and route choice. For the evacuation participation and departure time
choice we argue in favour of the simultaneous approach to dynamic evacuation demand prediction using the repeated binary logit
model. For the destination choice we show how further research is needed to generalize the current preliminary findings on
the location-type specific destination choice models. For the evacuation route choice we argue in favour of hybrid route choice
models that enable both following instructed routes and en-route switches. Within each of these discussions, we point at current
limitations and make corresponding suggestions on promising future research directions. 相似文献
987.
This study explores the relationships between adoption and consideration of three travel-related strategy bundles (travel
maintaining/increasing, travel reducing, and major location/lifestyle change), linking them to a variety of explanatory variables.
The data for this study are the responses to a fourteen-page survey returned by nearly 1,300 commuting workers living in three
distinct San Francisco Bay area neighborhoods in May 1998. We first identified patterns of adoption and consideration among
the bundles, using pairwise correlation tests. The test results indicate that those who have adopted coping strategies continue
to seek for improvements across the spectrum of generalized cost, but perhaps most often repeating the consideration of a
previously-adopted bundle. Furthermore, we developed a multivariate probit model for individuals’ simultaneous consideration
of the three bundles. It is found that in addition to the previous adoption of the bundles, qualitative and quantitative Mobility-related
variables, Travel Attitudes, Personality, Lifestyle, Travel Liking, and Sociodemographics significantly affect individual
consideration of the strategy bundles. Overall, the results of this study give policy makers and planners insight into understanding
the dynamic nature of individuals’ responses to travel-related strategies, as well as differences between the responses to
congestion that are assumed by policy makers and those that are actually adopted by individuals.
Sangho Choo is a Research Associate at The Korea Transport Institute. His research interests include travel demand modeling, travel survey methods with GPS, and travel behavior modeling. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, chair of the interdisciplinary Transportation Technology and Policy MS/PhD program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She has been modeling travel behavior and attitudes for more than 30 years. 相似文献
Patricia L. Mokhtarian (Corresponding author)Email: |
Sangho Choo is a Research Associate at The Korea Transport Institute. His research interests include travel demand modeling, travel survey methods with GPS, and travel behavior modeling. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, chair of the interdisciplinary Transportation Technology and Policy MS/PhD program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She has been modeling travel behavior and attitudes for more than 30 years. 相似文献
988.
Dynamic system‐optimal traffic assignment for a city using the continuum modeling approach 下载免费PDF全文
This paper presents a continuum dynamic traffic assignment model for a city in which the total cost of the traffic system is minimized: the travelers in the system are organized to choose the route to their destinations that minimizes the total cost of the system. Combined with the objective function, which defines the total cost and constraints such as certain physical and boundary conditions, a continuum model can be formulated as an optimization scheme with a feasible region in the function space. To obtain an admissible locally optimal solution to this problem, we first reformulate the optimization in discrete form and then introduce a heuristic method to solve it. This method converges rapidly with attractive computational cost. Numerical examples are used to demonstrate the effectiveness of the method. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
989.
The second-best congestion pricing schemes including common optimum, one cordon, and multiple cordons schemes are compared with the first-best optimum pricing scheme. A cross-subsidy effect exists in these second-best pricing models. However, the scheme with more cordons will diminish the cross-subsidy and approach an efficient and equitable outcome. The relative efficiency of a cordon pricing scheme for the case of Taipei metropolis is very high. One single cordon yields excellent performance of 93% relative efficiency. There might be some factors causing the good results: the uncongested traffic condition, the linear unit distance cost in traffic flow forming a nonlinear cost function, and the trip demands with continuous space and the same destination (the central business district) in the network. 相似文献
990.
The growth of a city or a metropolis requires well-functioning transit systems to accommodate the ensuing increase in travel demand. As a result, mass transit networks have to develop and expand from simple to complex topological systems over time to meet this demand. Such an evolution in the networks’ structure entails not only a change in network accessibility, but also a change in the level of network reliability on the part of stations and the entire system as well. Network accessibility and reliability are popular measures that have been widely applied to evaluate the resilience and vulnerability of a spatially networked system. However, the use of a single measure, either accessibility or reliability, provides different results, which demand an integrated measure to evaluate the network’s performance comprehensively. In this paper, we propose a set of integrated measures, named ACCREL (Integrated Accessibility and Reliability indicators) that considers both metrics in combination to evaluate a network’s performance and vulnerability. We apply the new measures for hypothetical mass transit system topologies, and a case study of the metro transit system in Seoul follows, highlighting the dynamics of network performance with four evolutionary stages. The main contribution of this study lies in the results from the experiments, which can be used to inform how transport network planning can be prepared to enhance the network functionality, thereby achieving a well-balanced, accessible, and reliable system. Insights on network vulnerability are also drawn for public transportation planners and spatial decision makers. 相似文献