An Impact of Gas Prices on Transit Demand Using a Time-series Analysis and a Regression Analysis
Abstract Depending most of its energy sources on foreign countries, Korea efforts to reduce energy consumption in transportation. While studies on the relationship between gas price and transportation demand are many in number, most previous studies have focused on automobile and Seoul. This study analyzes the impact of gas price on transit (bus and subway) demand using monthly data and for various metropolitan areas (Seoul, Busan, Daejeon, Daegu and Gwangju). The research utilizes a time-series model and a multiple regression model, and calculates modal demand elasticities of gas price. The result shows that elasticities of subway demand with respect to gas price is higher than those of bus demand. In addition, elasticities of predominantly automobile cities are more likely to be more sensitive to gas price than those of cities with well-structured transit system.국내에서 소비되는 에너지의 대부분을 해외에 의존하고 있는 우리나라는 교통부문에서도 에너지 절감을 위해 많은 노력을 하고 있다 . 휘발유가격과 교통수요와의 관계는 국내외적으로 꾸준히 연구되어 왔으나 국내 선행연구는 승용차 및 수도권 중심으로 연구되어 왔다 . 본 연구에서는 휘발유가격이 대중교통수요에 미치는 영향을 분석하며 월별 자료를 활용하여 대중교통 수단별 (버스, 도시철도) 및 광역권별(수도권, 부산, 대전, 대구, 광주)로 실증적으로 비교분석했다. 분석을 위해 시계열모형과 다중회귀모형을 사용하였으며 회귀모형의 계수를 활용하여 유가에 대한 대중교통수요의 탄력성을 비교하였다 . 유가에 대한 수요탄력성이 버스보다 도시철도가 높게 나타났고 , 대중교통체계가 잘 갖춰진 수도권보다 승용차 의존적인 지방 광역권이 유가에 더 민감한 것으로 나타났다 .
Rising Gas Price and Transit Ridership
In July 2008, gas prices peaked at unprecedented levels in both nominal and real dollars. Americans also took more transit trips in 2008 than in any year since 1956. Past research has demonstrated a correlation between increases in gas price and increases in transit ridership. Using the Philadelphia, Pennsylvania, metropolitan area as a case study, this research confirms and provides new insight into this relationship. Multivariate linear regressions were developed both to demonstrate and to measure the correlation while accounting for seasonal differences and to provide insight into what future gas price scenarios could mean for a transit system in a city like Philadelphia. One set of models was developed for the Regional Rail system and another was developed for the City Transit system. Both models demonstrated correlations of statistical significance. Comparison of the models showed that the price of gas had both a more significant correlation with and a higher impact on Regional Rail rider-ship than on City Transit ridership. The models were also used to explore the cross elasticity for transit demand. The results suggest various cross elasticities of between 0.15 and 0.23 for City Transit services and between 0.27 and 0.38 for Regional Rail services. The problems with attempting to isolate a value for cross elasticity are discussed. This analysis also explores the possibilities of a nonlinear relationship that explains past trends and discusses the difficulties in using these models to predict future transit demand.
Research on integral error calibrating system of high-voltage electric energy measurement device
To the question that there is no accuracy grade to the existed HV energy measuring system, a design scheme to calibrate the integer error of HV energy measuring device is provided in this paper. The hardware of the calibrating system, including test power source, signal source, power benchmark system, power source measuring and regulating circuit, has been introduced in detail. The function of the monitoring and operating software is also discussed in the paper.