Repetition and Variability in Urban Travel

Most travel models and theories assume the existence of habitual behavior, yet few empirical studies have examined the question of how much repetition or variability characterizes daily travel. We first review the arguments for expecting both repetition and variability in urban travel-activity patterns and then conduct an empirical analysis of repetition and variability in travel over a five-week period. The results show that, whereas many behaviors that make up the daily pattern are highly repetitious (they occur with high frequency over the 35 days), the similarity between daily travel patterns on different days in an individual's longitudinal record is quite low. Even the day that is the most typical of the individual's travel is a poor indicator of that person's overall travel pattern. Moreover, we found that each person generates several archetypical daily patterns over 35 days, and this finding has important implications for data collection and modeling in studies of urban travel.     

Levels of Spatial Knowledge and Urban Travel Modeling

Models of spatial behavior implicitly assume a direct connection between the individual's utility function and his actual behavior. In reality, this link is mediated by the extent and quality of his spatial knowledge. Without sufficient knowledge, the chosen behavior will be selected from a small number of known alternatives. Using a route choice study in Beer Sheva, this paper investigates the extent and the level of spatial knowledge exhibited by the public in episodic, nonroutine travel. It demonstrates that their knowledge stabilizes at the intermediate “route level,” whereas only professional drivers attain the highest “survey level.” The cognitive opportunity sets of drivers at the route level are idiosyncratic. Accordingly, route selection by the general public was found largely unpredictable. Implications for urban travel modeling are discussed.     

The Evaluation of Urban Public Facility Location: An Alternative to Benefit-Cost Analysis

This paper attempts to overcome some specific problems which exist with the use of benefit-cost analysis in evaluating the impact of public facilities. The concepts developed explicitly recognize the importance of the spatial distribution of impacts and the fact that tastes can differ substantially among people. By utilizing the concepts of the generalized environment and of place utility, a more general and valuable conceptual model can be developed which may be useful in preventing much current conflict over public investment decisions. The model has an explicit concern with the problem of equity and is thus only a small step in a growing field of inquiry within geography.     

大型旅行社空间扩张的区位选择--"上海春秋"案例

旅行社是介于旅游吸引物与旅游者之间的组织者,它对地理区位的选择是本文的探讨重点。本文以上海春秋国际旅行社为例,归纳它在国内宏、微观选址的经验,得到其以省会城市、著名旅游城市、新兴经济发达城市为节点的宏观网络和以中心门市及社区门市为节点的微观网络;根据区位因素理论,初步分析了与旅行社空间区位选择有关的一些因素,包括对市场、成本等一般性因素的分析和对行为等特殊性因素的分析;最后,提出旅行社的区位扩张不仅要重视物理空间,也要重视网络信息空间。     

An Economic-Mathematical Model of the Location of Farm Production by Regions of the Soviet Union

A standard model for the optimal use of production capacities is modified by two additional conditions to yield a model of the optimal location of agricultural production. The two conditions are designed to take account of the soil-depleting effect of various crop groups and of crops whose sown areas must be limited for various reasons. The model was used in 1961 and 1962 for 16 crops and 24 regional units.     

A Model for Location of Capacitated Alternative-Fuel Stations

Increased interest in alternative fuels is attributable, in part, to rising oil prices and increasing concern about global warming. A lack of a refueling infrastructure, however, has inhibited the adoption of alternative-fuel vehicles. Little economic incentive exists to mass-produce alternative-fuel vehicles until a network of stations exists that can refuel a reasonable number of trips. The flow refueling location model (FRLM) was developed to minimize the investment necessary to create a refueling infrastructure by optimizing the location of fueling stations. The original uncapacitated FRLM assumes that the presence of a refueling station is sufficient to serve all flows passing through a node, regardless of their volume. This article introduces the capacitated flow refueling location model that limits the number of vehicles refueled at each station. It also introduces a modified objective function maximizing vehicle-miles traveled instead of trips, applies both models to an intercity network for Arizona, and formulates several other extensions.     

中国出境旅游市场失效性分析及其对策

本分析了出境旅游市场失效的现状及其根源,并提出解决出境旅游市场失效性的对策。     

The Location of Services in the Urban Hierarchy and the Regions of the United States

We use regression and factor analyses to explain intermetropolitan variation in the proportion of jobs in disaggregated service sectors in American metropolitan areas. Central place theory postulates of centrally located establishments serving a surrounding complementary region partially explain the positive relationship between metropolitan size and the proportion of jobs in an area in services. Regional variation in demand following several decades of substantial shifts in population and economic output is an additional influence. Intermetropolitan clustering of service sectors is also occurring. A factor analysis of employment proportions in twenty-two disaggregate service sectors identified five intersectoral service clusters. The factor analysis accounted for substantially more variance than the regression equations. We interpret this result as evidence of the emergence of service-based spatial industrial complexes. We argue that agglomeration of information-intensive intermediate services is driven by an attraction to labor markets endowed with pools of skilled professionals who can flexibly apply their talents in a variety of sectors. Unusual demographic characteristics of some metropolitan areas probably explain clusters of final demand services.     

高校学生旅游市场营销策略分析

高校学生是一个特定的旅游需求和消费群体,也是一个极富增长潜力的细分市场。本文通过对高校学生出游动机和出游特点的分析,探讨了该目标市场的成长空间;通过SWOT分析,论证了开发高校学生旅游市场的必要性和可行性。笔者以广东省肇庆市为案例,结合当地资源禀赋特征和高校学生的旅游需求特征,探讨了为高校学生设计定制化旅游产品的方法,并就促销手段和服务意识两方面提出了针对该细分市场的营销策略。     

A Climatic Model of Urban Energy Budgets

A deductive model of the energy budgets of urban landscapes, based on the exchanges of energy, mass, and momentum, is introduced. The absorption of shortwave and longwave radiation and their dissipation via the channels of reradiation, convection, conduction, and evaporation are generated by the model in order to simulate the interplay of the many energy cascades among the myriad of city surfaces. A city can be geographically analyzed by determining its energy budget and resultant surface temperatures on a block-by-block basis. In spite of some simplifying assumptions, the predictions of surface temperatures of this initial model compare favorably with observations.     

A Partitioning Model of Urban Retail Structure

A model based on renewal theory generates the number of retail establishments in a place as the outcome of a competitive partitioning process. The available market, measured for example by population or by existing retail sales, is shared among businesses until no market potential market remains. Competing businesses obtain different shares of the market, and the number of establishments is predicted as a discrete random variable. Several alternative formulations are presented of varying generality. One version is successfully tested, using GLIM, on ten business types (SIC two-digit classes) in 232 cities of New York State for 1977 and 1987. The model correctly predicts the form and the variance structure of the relationship between number of establishments and place size. It is shown how the model may be combined with models of city-size distributions to predict aggregate frequency distributions of retail establishments across urban systems.