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Travel time uncertainty has significant impacts on individual activity-travel scheduling, but at present these impacts have not been considered in most accessibility studies. In this paper, an accessibility evaluation framework is proposed for urban areas with uncertain travel times. A reliable space-time service region RSTR model is introduced to represent the space-time service region of a facility under travel time uncertainty. Based on the RSTR model, four reliable place-based accessibility measures are proposed to evaluate accessibility to urban services by incorporating the effects of travel time reliability. To demonstrate the applicability of the proposed framework, a case study using large-scale taxi tracking data is carried out. The results of the case study indicate that the proposed accessibility measures can evaluate large-scale place-based accessibility well in urban areas with uncertain travel times. Conventional place-based accessibility indicators ignoring travel time reliability can significantly overestimate the accessibility to urban services.

Refined instruments of multidimensional country image scale are applied along with structural equation modeling (SEM), paired-samples t-test, and compared means statistical techniques to analyze 203 structured questionnaires collected by combining mall-intercept with online surveys to study whether country image effectively influences consumers’ quality evaluation of intangible services. The context is airlines from three sourcing countries categorized as developing and developed economy entities. The stream of country image research to date has been disproportionately focused on products. The results of this investigation, based on the theory of reasoned action by using the hierarchy-of-effects model, demonstrate that a single cue, country image, positively affects consumers’ evaluation of intangible services. These results supplement the long disregarded research in services; especially in the ever-increasing globalization of the service sector in the new information-based economy.

This paper presents a detailed design and analysis of a resonant dc—link inverter driving system. A 3—phase, 4KW resonant dc—link inverter has been constructed and successfully tested to drive a permanent magnet synchronous system based on a field-oriented control. Details of the design, analysis and implementation of the whole drive system are described. In addition, the efficiency analysis of the whole system, which consists of an inverter and a motor, is discussed. Experimental case studies that correlate simulation and measurement results are provided. The experimental results not only validate the theoretical development but also prove that this new system has better performance than traditional systems.