نتایج جستجو برای: and rail costs

تعداد نتایج: 16840016  

2012
M. Oregui Z. Li

Rail joints have a shorter service life than most other railway track components. The discontinuity between rail ends turns the rail joint into a weak spot, and consequently, into a track component demanding more frequent maintenance measures, which result in high maintenance costs. Moreover, difficulties are often found when assessing the damage condition of rail joints since damage conditions...

2015
Andrew S.J. Smith Phill E. Wheat Chris A. Nash

This paper provides an up-to-date reviewof the previous literature concerning the impact of passenger rail franchising on productivity and costs in Britain, and also presents important new evidence. In particular, the extension in time of previously-used datasets offers the first opportunity to study the impacts of re-franchising. The previous literature emphasised the failure of franchising to...

ژورنال: Journal of Railway Research 2014
Fazel, Seyed Saeed ,

Due to the high potential of urban rail transport systems as an effective solution to improve urban mobility services, these systems have faced an increasing demand in recent years. High capacity, reliability and absence of local emissions are some of the most promising advantages of these transportation systems. However, with the increase in capacity demands, energy costs and environmental ...

2001
JONATHAN RICHMOND A. Alfred Taubman John F. Kennedy

New transit capital expenditures are typically evaluated in isolation from the transit/transport systems to which they belong. Problems with reporting performance elements such as ridership and costs are discussed. A focus on evaluating the total transport systems impact of new transit project implementation is called for. On this basis, new US rail transit systems have generally performed poor...

Train braking energy regeneration in urban electrical rail transportation systems can reduce energy consumption and operational cost of the system. In this paper, optimal design of an onboard energy storage system (OESS) with volume constraint is presented for urban electrical rail transportation systems (ERTS). Onboard super-capacitors are considered as the storage system. The objective functi...

Journal: :Environmental science & technology 2005
Joule A Bergerson Lester B Lave

We examine the life cycle costs, environmental discharges, and deaths of moving coal via rail, coal gas via pipeline, and electricity via wire from the Powder River Basin (PRB) in Wyoming to Texas. Which method has least social cost depends on how much additional investment in rail line, transmission, or pipeline infrastructure is required, as well as how much and how far energy is transported....

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه پیام نور - دانشگاه پیام نور استان تهران - دانشکده علوم اجتماعی و اقتصادی 1389

abstract nowadays, the science of decision making has been paid to more attention due to the complexity of the problems of suppliers selection. as known, one of the efficient tools in economic and human resources development is the extension of communication networks in developing countries. so, the proper selection of suppliers of tc equipments is of concern very much. in this study, a ...

2013
Francisco Calvo Juan de Oña Andrew Nash

A pricing methodology adapted to specific railroad infrastructures and the trains that use them is one way to ensure that railroad networks used by several different operators are used optimally. The diversity of railway networks (new lines and old lines) and services (long-distance and suburban passenger trains, freight trains, etc.) make it difficult to develop such a pricing methodology. Thi...

ژورنال: اقتصاد مالی 2012

چکیده خدمات ریلی از مقوله های مهم نظام حمل و نقل ایران است که در دهه اخیر توجه بیشتری به این بخش شده است. با این وجود بهینه یابی قیمت در عرضه این خدمات همواره مورد مناقشه بوده است، و بروز رسانی یا ترقی قیمت در ماههای اخیر بسیار مورد انتقاد بوده است. آنچه در این پژوهش آزمون شده است اثرات ناشی از ترقی قیمت ناشی از عوامل هزینه ای و کیفی بر تقاضای عموم است. ملاحظه شده است که ارتقاء قیمت بر میزان ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - پژوهشکده مهندسی فرایند 1395

abstract: mineral scaling in oil and gas production equipment is one of the most important problem that occurs while water injection and it has been recognized to be a major operational problem. the incompatibility between injected and formation waters may result in inorganic scale precipitation in the equipment and reservoir and then reduction of oil production rate and water injection rate. ...

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