bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research contributions to managing transit service reliability
Authors: Abkowitz Mark , Tozzi John 
Published: January 2010

AbstractService reliability problems are a major concern shared by transit system users and operators. Unreliable service leads to additional vehicle requirements and higher operating costs; passengers suffer increased wait time and higher travel time uncertainty, leading to a general dissatisfaction with service and the possibility of seeking other means of transport. Because of the significance of this problem, considerable research attention has been focused in recent years on developing ways to improve service reliability.This paper examines contributions which have been made to managing transit service reliability. This topic encompasses the subjects of vehicle run time, run time variation, headway variation, passenger wait time, and reliability control. Both theoretical and empirical approaches have been undertaken, and each has contributed to our knowledge in addressing the overall problem. Significant contributions to the state‐of‐the‐art are reported and the implications on present practice are discussed.
Geographical variation in traffic‐related mortality and morbidity among pedestrians in Quebec, 1983‐1988
Authors: Joly Marie‐France , Thouez Jean‐Pierre , Bourbeau Robert , Bussière Yves , Rannou André 
Published: January 2010

AbstractIn this study we analyze the dmographic and geographical distribution of pedestrian accidents (n=28,452) in the Quebec Municipalités régionales de comté (MRC) reported between January 1, 1983 and December 31, 1988. In order to be able to make comparisons between MRCs, we have created in Comparative Mortality Index and a Comparative Morbidity Index. We use a logistic regression model to single out explanatory factors. The main tendencies which are apparent in the demographic analysis are an overrepresentation of young persons and elderly persons in the accident statistics, and that men are more at risk than women. Men 15 years and under and men 65 years and over are more at risk of being involved in a fatal pedestrian accident. The geographic analysis show that among men, the average mortality rate is one and a half times greater in rural MRCs than in urban MRCs; among women, rural mortality is two and a half times greater than urban mortality. In the case of non‐severe injuries we note an over‐representation of urban MRCs. Young persons 15 years or less who live in an urban, populated zone are those most at risk of being involved in a pedestrian accident. Identifying high risk groups or areas is a prerequisite step for injury prevention and control.
Effect of local operational constraints on runway capacity ‐ A case study
Authors: Fan Henry S. L. 
Published: January 2010

AbstractThe estimation of runway capacity is important in airport planning and operational analysis. Standard procedures for capacity determination typically assume that there is no constraint on aircraft operations and do not provide good estimates when constraints exist. This paper presents a study of runway capacity at Singapore Changi Airport in which local operational constraints are taken into account. In addition, the impacts on capacity due to marine vessel crossings in a shipping channel near the airport, and the timing for implementation of simultaneous, independent instrument approach procedures are also investigated. The levels of annual aviation demand that could be served without excessive delays to aircraft under various operating scenarios are estimated.
Safe design of personal rapid transit systems
Authors: Anderson J. Edward 
Published: January 2010

AbstractThe safety of personal rapid transit systems involves careful attention to all features of the design such as the use of a hierarchy of fault‐tolerant redundant control systems, bi‐stable fail‐safe switching, back‐up power supplies, vehicle and passenger protection, and attention to the interaction of people with the system. Safety, together with reliability and adequate capacity, must be achieved while making the system economically attractive, hence techniques to achieve these goals at minimum life‐cycle cost are primary in PRT design. Building on theory of safe, reliable, environmentally acceptable, and cost‐effective design of PRT systems developed during the 1970′s, in 1981 the author and his colleagues initiated design of a new PRT system, now called Taxi 2000. The paper describes the relevant features of Taxi 2000 and principles of safe design incorporated into it.
Procurement methods for automated guideway transit systems
Authors: Jakes Andrew S. 
Published: January 2010

AbstractProcurement of an Automated Guideway Transit (AGT) system is a relatively new process for many procuring agencies worldwide. Outside of large airports, no single transit market sector has enough experience to establish well proven procurement methodologies for innovative transit technologies. Several methods, however, have emerged recently which, together with more conventional approaches, make the decision making process quite complex. The objective of this article is to review currently used and recently considered procurement methods and recommend a methodology for their selection depending on specific project requirements.
Automated transit and land use intentions: Alternate scenarios with PRT and shuttle/loop technologies
Authors: Warren Roxanne 
Published: January 2010

AbstractEcological impacts of urban sprawl on the land, as well as forces that engender sprawl are outlined. Long‐range land use priorities for more compact, transit‐oriented development (TOD) are seen as ecological imperatives. While Personal Rapid Transit (PRT) could solve some congestion, it does not address these priorities. Several assumptions that underlie the PRT concept, particularly the premise that denser land use is per se socially undesirable, are challenged in terms of historical precedent. Rather, the explosive scale of ubiquitous motoring is seen as the key component of today's resistance to dense development. With peripheral parking and medium‐capacity AGT links to regional transportation networks, new TOD could be redefined as pedestrian‐zoned and richly landscaped urban neighborhoods; this would help resolve essential traffic and environmental barriers to its realization. The simpler automated shuttle and loop technologies are seen as more compact and potentially affordable for this purpose. Steps that could help open the way toward realization of such development are discussed.
Dense network traffic models, Travel time reliability and traffic management. I: General introduction
Authors: Taylor Michael A P 
Published: January 2010

AbstractThis paper is the first of a pair of papers discussing two main themes concerning dense network modelling. These themes are: (1) the changing nature of traffic management technology and the underlying objectives behind traffic management practice, and (2) the use of measures of network reliability in models, especially as an element of the evaluation of alternative network configurations. This paper considers the role and function of dense network models, and their relationships with other transport network models on the basis of the hierarchical view of models. It then explores the peculiar characteristics of dense network models and provides examples of typical models. Changing needs for modelling capabilities, in terms of the evolution of traffic management technology and practice are discussed, pointing the way to future model developments. The companion paper develops the second theme through the definition and application of a set of network reliability indices that may be applied to different trip movements.
Dense network traffic models, travel time reliability and traffic management. Ii: Application to network reliability
Authors: Taylor Michael A P 
Published: January 2010

AbstractThis paper is the second of a pair of papers discussing two main themes concerning dense network modelling. These themes are: (1) the changing nature of traffic management technology and the underlying objectives behind traffic management practice, and (2) the use of measures of network reliability in models, especially as an element of the evaluation of alternative network configurations. This paper develops and applies the second theme, the use of network reliability concepts in the evaluation of traffic networks, through consideration of variations in travel times, distinction between local street and arterial road networks, and the definition and application of a set of reliability indices that may be used to study different trip movements in a network. It indicates how these indices may be used in appraising different traffic management plans for a dense network of local streets and arterial roads, using a case study application.
Estimation of link performance functions from incomplete flow data
Authors: Hazelton Martin L. , Pueschel John 
Published: January 2010

AbstractDespite the pivotal importance of link performance functions to models of transport systems, relatively little work has been done on practical aspects of estimating these functions from observed data. Furthermore it is difficult to find any examples in the literature of estimated urban link performance functions faithfully reproducing theoretical travel time‐flow relationships. One reason for the paucity of research in this area is the difficulty and expense of obtaining the requisite data. The increase in automatic collection of traffic flow data goes part way to resolving this problem, but matching such flows to manually recorded travel times can present considerable statistical difficulties in the estimation procedure. This paper considers the estimation of link performance functions from a combination of automatically recorded traffic counts and travel collected by hand, using a non‐standard statistical methodology. The study is motivated by a set of data of precisely this type, from the UK city of Leicester.
Transport economics: A personal view
Authors: Hensher David A. 
Published: January 2010

AbstractThe field of transportation attracts individuals from diverse backgrounds, seeking to make contributions to policy, planning, operations and strategy. Economists are one of the more visible subsets of players, who bring a specific focus to the transport problem. The key theme of this paper is economic efficiency and ways that transport economics seeks to achieve efficient outcomes in the presence of markets and institutions that to varying degrees distort the potential to fulfil this primary goal. We review some of the recent contributions to the literatures on institutional and market reform, travel choice and demand. As we enter the next century, there is a sense of promoting ‘back to basics’ (and redefinition of what skills transport specialists will require) in seeking a better understanding of the role of markets and institutions in guiding the destiny of the transport sector.
New waves in transportation in North‐Eastern Europe
Authors: Himanen Veli 
Published: January 2010

AbstractNorth‐Eastern Europe is a peripheral area around the Baltic Sea. In some parts i.e. Scandinavia high living standards including developed transport systems exist when at the same time rapid changes in the way of living in other parts ‐ Poland, the Baltic Countries and Russia ‐ are ongoing. Transport policies in the European Union are caught between demands for improved mobility and the concern on the environmental protection. In the former socialist countries the environmental issues are subdued by the demands for efficient transport. A fixed road and rail connection between Denmark and Sweden will change the transport geography of the western part of the area. Also the integration of the Baltic States and Poland to the Union will inside a few years change the economic and by that way also transport structure. After a short presentation of the geography and history the current European transport landscape will be described and current transport policies reviewed. Then some topics on the major changes during the last decennia as well as future studies will be presented. The paper draws heavily from the research projects ‐ SAMI, START and STEMM ‐ financed by the European Commission DGVII.
Transport planning for urban areas: A retrospective look and future prospects
Authors: Meyer Michael D. 
Published: January 2010

AbstractThis paper examines the evolution of urban transport planning since the 1960′s, identifies the key trends that have influenced such planning, describes the current state of urban transport planning, and speculates on the important characteristics that will influence urban transport planning over the next several decades. Fifteen planning conferences since 1957 are reviewed to show the changing perspectives on planning from the professional community. Ten areas are identified that will provide special challenge to future transport planners—demographic changes, the importance of economic production and market forces for transport system performance, multimodal perspectives for transport planning, adopting an operations focus, an important role for technology, developing a sense of community, laying the groundwork for pricing, integrating transport decision making with growth management, transport planning within a sustainability framework, and providing greater accountability of the decision making and planning processes.
Modelling the provision of transport with planned or market‐determined public transport services
Authors: Allsop Richard E. 
Published: January 2010

AbstractImplications of the difference between planned and market‐determined public transport services for the modelling of the transport system and its use are examined. In the former case, the task for government seeking to optimise performance of the transport system has a standard bi‐level form, but in the latter case, the lower‐level problem in the bi‐level formulation is to determine mutually consistent solutions to a pair of optimisation problems. The relevance of the mutually consistent solution in this context is contrasted with its sometimes misleading role in the context of optimisation of urban traffic signal control.
Operational objective functions in designing public transport routes
Authors: Ceder Avishai 
Published: January 2010

AbstractThis work proposes a framework for the construction of the operational objective functions of the public transport network design problem. This framework takes into account the passengers, operator and community interests. The methodology presented combines the philosophy of the mathematical programming approaches with decision‐making techniques, so as to allow the user to select from a number of alternatives. The nature of the overall formulation is nonlinear and mixed integer programming.
A system dynamics approach to land use/transportation system performance modeling Part I: Methodology
Authors: Haghani Ali , Lee Sang Y. , Byun Joon H. 
Published: January 2010

AbstractThis paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD.In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance.While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited due to data availability, the results indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling.
Network equilibrium for congested multi‐mode networks with elastic demand
Authors: Wu Z. X. , Lam William H. K. 
Published: January 2010

AbstractThis paper proposes an elastic demand network equilibrium model for networks with transit and walking modes. In Hong Kong, the multi‐mode transit system services over 90% of the total journeys and the demand on it is continuously increasing. Transit and walking modes are related to each other as transit passengers have to walk to and from transit stops. In this paper, the multi‐mode elastic‐demand network equilibrium problem is formulated as a variational inequality problem where the combined mode and route choices are modeled in a hierarchical logit structures and the total travel demand for each origin‐destination pair is explicitly given by an elastic demand function. In addition, the capacity constraint for transit vehicles and the effects of bi‐directional flows on walkways are considered in the proposed model. All these congestion effects are taken into account for modeling the travel choices. A solution algorithm is developed to solve the multi‐mode elastic‐demand network equilibrium model. It is based on a Block Gauss‐Seidel decomposition approach coupled with the method of successive averages. A numerical example is used to illustrate the application of the proposed model and solution algorithm.
Eukaryotic cold shock domain proteins: highly versatile regulators of gene expression
Authors: Mihailovich Marija , Militti Cristina , Gabaldón Toni , Gebauer Fátima 
Published: January 2010

AbstractCold shock domain (CSD)‐containing proteins have been found in all three domains of life and function in a variety of processes that are related, for the most part, to post‐transcriptional gene regulation. The CSD is an ancient β‐barrel fold that serves to bind nucleic acids. The CSD is structurally and functionally similar to the S1 domain, a fold with otherwise unrelated primary sequence. The flexibility of the CSD/S1 domain for RNA recognition confers an enormous functional versatility to the proteins that contain them. This review summarizes the current knowledge on eukaryotic CSD/S1 domain‐containing proteins with a special emphasis on UNR (upstream of N‐ras), a member of this family with multiple copies of the CSD.
Phyto‐bioconversion of hard coal in the Cynodon dactylon/coal rhizosphere
Authors: Igbinigie Eric E. , Mutambanengwe Cecil C. Z. , Rose Peter D. 
Published: January 2010

AbstractFundamental processes involved in the microbial degradation of coal and its derivatives have been well documented. A mutualistic interaction between plant roots and certain microorganisms to aid growth of plants such as Cynodon dactylon (Bermuda grass) on hard coal dumps has recently been suggested. In the present study coal bioconversion activity of nonmycorrhizal fungi was investigated in the C. dactylon/coal rhizosphere. Fungal growth on 2% Duff‐agar, gutation formation on nitric acid treated coal and submerged culture activity in nitrogen‐rich and ‐deficient broth formed part of the screening and selection of the fungi. The selected fungal isolates were confirmed to be found in pristine C. dactylon/coal rhizosphere. To simulate bioconversion, a fungal aliquot of this rhizosphere was used as inoculum for a Perfusate fixed bed bioreactor, packed with coal. The results demonstrate an enhanced coal bioconversion facilitated by low molecular weight organics and the bioconversion of coal may be initiated by an introduction of nitrogen moieties to the coal substrate. These findings suggest a phyto‐bioconversion of hard coal involving plant and microbes occurring in the rhizosphere to promote the growth of C. dactylon. An understanding of this relationship can serve as a benchmark for coal dumps rehabilitation as well as for the industrial scale bioprocessing of hard coal.
Exploiting biocatalysis in peptide self‐assembly
Authors: Williams Richard J. , Mart Robert J. , Ulijn Rein V. 
Published: January 2010

AbstractThis review article covers recent developments in the use of enzyme‐catalyzed reactions to control molecular self‐assembly (SA), an area that merges the advantages of biocatalysis with soft materials self‐assembly. This approach is attractive because it combines biological (chemo‐, regio‐, and enantio‐) selectivity with the versatility of bottom up nanofabrication through dynamic SA. We define enzyme‐assisted SA (e‐SA) as the production of molecular building blocks from nonassembling precursors via enzymatic catalysis, where molecular building blocks form ordered structures via noncovalent interactions. The molecular design of SA precursors is discussed in terms of three key components related to (i) enzyme recognition, (ii) molecular switching mechanisms, and (iii) supramolecular interactions that underpin SA. This is followed by a discussion of a number of unique features of these systems, including spatiotemporal control of nucleation and structure growth, the possibility of controlling mechanical properties and the defect correcting and component selecting capabilities of systems that operate under thermodynamic control. Applications in biomedicine (biosensing, controlled release, matrices for wound healing, controlling cell fate by gelation) and bio(nano)technology (biocatalysts immobilization, nanofabrication, templating, and intracellular imaging) are discussed. Overall, e‐SA allows for unprecedented control over SA processes and provides a step forward toward production of nanostructures of higher complexity and with fewer defects as desired for next generation nanomaterials. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94:107–117, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Wall effects in continuous microfluidic magneto‐affinity cell separation
Authors: Wu Liqun , Zhang Yong , Palaniapan Moorthi , Roy Partha 
Published: January 2010

AbstractContinuous microfluidic magneto‐affinity cell separator combines unique microscale flow phenomenon with advantageous nanobead properties, to isolate cells with high specificity. Owing to the comparable size of the cell–bead complexes and the microchannels, the walls of the microchannel exert a strong influence on the separation of cells by this method. We present a theoretical and experimental study that provides a quantitative description of hydrodynamic wall interactions and wall rolling velocity of cells. A transient convection model describes the transport of cells in two‐phase microfluidic flow under the influence of an external magnetic field. Transport of cells along the microchannel walls is also considered via an additional equation. Results show the variation of cell flux in the fluid phases and the wall as a function of a dimensionless parameter arising in the equations. Our results suggest that conditions may be optimized to maximize cell separation while minimizing contact with the wall surfaces. Experimentally measured cell rolling velocities on the wall indicate the presence of other near‐wall forces in addition to fluid shear forces. Separation of a human colon carcinoma cell line from a mixture of red blood cells, with folic acid conjugated 1 µm and 200 nm beads, is reported. Biotechnol. Bioeng. 2010; 106: 68–75. © 2010 Wiley Periodicals, Inc.