As state transportation planners seek to build or support sustainable transportation systems in an era of economic challenges, they find few publicly available rail analysis models for stakeholders to examine the environmental impacts, socio-economic effects and costs associated in investing in rail infrastructure. This paper, taken from a University Transportation Center Program (UTCP Region 6...

This report evaluates criticism of rail transit systems. It examines claims that rail transit is ineffective at increasing public transit ridership and improving transportation system performance, that rail transit investments are not cost effective, and that transit is an outdated form of transportation. It finds that critics often misrepresent issues and use biased and inaccurate analysis. Th...

Presented is a 0.9 V rail-to-rail constant gm CMOS amplifier input stage consisting of complementary differential pairs and a gm control circuit. The gm control circuit eliminates the gm dead zone, which occurs in the conventional rail-to-rail amplifier with ultra-low supply voltages. The proposed amplifier input stage has a constant gm that varies by +2.3% for rail-to-rail input common-mode le...

Preventing broken-rail-caused derailments is a high priority for the rail industry and government. The current practice is to periodically inspect rails using non-destructive technologies such as ultrasonic rail inspection. Determining the optimal inspection frequency is a critical decision in railway infrastructure management. The objective of this paper is to develop an analytical framework t...

Rail surface defects such as the abrasion, scratch and peeling often cause damages to the train wheels and rail bearings. An efficient and accurate detection of rail defects is of vital importance for the safety of railway transportation. In the past few decades, automatic rail defect detection has been studied; however, most developed methods use optic-imaging techniques to collect the rail su...

The type and magnitude of loads passing through the track superstructure have a great impact on both the design and the performance of concrete sleepers and fastening systems. To date, the majority of North American research focusing on quantifying rail infrastructure loading conditions has been conducted on heavy-haul freight railroads. However, the results and recommendations from these studi...

Compared to fibre-dominated behaviour, a response dominated by the matrix under shear loading can considerably limit load-bearing capability and restrict utilisation of composite materials. It is therefore practically significative understand This paper presents detailed experimental numerical investigation on fracture behaviour laminates subjected shear-dominated loading. Composite specimen wi...

OBJECTIVE To evaluate the experience of 37 years regarding etiology, complications and evolving practice of the management of stricture urethra patients at the Sindh Institute of Urology and Transplantation, Karachi. METHODS The retrospective descriptive study included 1600 cases of stricture urethra admitted to the Urology Section of the institute from 1972 to 2009. Files of all patients wer...

This chapter describes basic logic circuits. This can be seen as largely background material for applications in later chapters in the design of dividers and phase detectors in frequency synthesizers. The types of logic discussed will be CMOS rail-to-rail logic, CMOS current mode logic (CML), bipolar CML, and bipolar emitter coupled logic (ECL). Note that CML is a general term and applies to bo...

This study evaluates rail transit benefits based on a comprehensive analysis of transportation system performance in major U.S. cities. It finds that cities with large, wellestablished rail systems have significantly higher per capita transit ridership, lower average per capita vehicle ownership and annual mileage, less traffic congestion, lower traffic death rates, lower consumer expenditures ...