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Effects of piezoelectric potential on the transport characteristics of metal-ZnO nanowire-metal field effect transistor

Gao, Zhiyuan; Zhou, Jun; Gu, Yudong; Fei, Peng; Hao, Yue; Bao, Gang; Wang, Zhong Lin
Fonte: American Institute of Physics Publicador: American Institute of Physics
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.91%
We have investigated the effects of piezoelectric potential in a ZnO nanowire on the transport characteristics of the nanowire based field effect transistor through numerical calculations and experimental observations. Under different straining conditions including stretching, compressing, twisting, and their combination, a piezoelectric potential is created throughout the nanowire to modulate∕alternate the transport property of the metal-ZnO nanowire contacts, resulting in a switch between symmetric and asymmetric contacts at the two ends, or even turning an Ohmic contact type into a diode. The commonly observed natural rectifying behavior of the as-fabricated ZnO nanowire can be attributed to the strain that was unpurposely created in the nanowire during device fabrication and material handling. This work provides further evidence on piezopotential governed electronic transport and devices, e.g., piezotronics.

Thermodynamic and transport property modeling in super critical water

Kutney, Michael C. (Michael Charles)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 418 p.
ENG
Relevância na Pesquisa
46.32%
Supercritical water oxidation (SCWO) is a thermally-based, remediation and waste-treatment process that relies on unique property changes of water when water is heated and pressurized above its critical point. Above its critical point (374.1 ⁰C and 220.9 bar), water becomes gas-like and somewhat non-polar due to the decrease in density and disruption of the hydrogen-bond network. When oxidants and organic compounds are combined with supercritical water (SCW), they rapidly form a single phase, and these organics are quickly and completely oxidized to simple molecules including water and carbon dioxide. Laboratory research is currently being conducted in order to increase the level of understanding of key SCWO areas including reaction kinetics, corrosion, and salt-related phenomena and in order to develop realistic SCWO process and fluid-dynamic simulators. Understanding the phenomena in each of these areas requires accurate thermodynamic- and transport-property predictions. However, these often do not exist. Furthermore, available correlations are often used in operating regimes where they were not originally validated, thereby potentially reducing their accuracy. This thesis focuses on the development of accurate thermodynamic-property and diffusivity- transport-property models for use at typical SCWO operating conditions...

On Measuring the Benefits of Lower Transport Costs

Jacoby, Hanan G.; Minten, Bart
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
36%
Despite large amounts invested in rural roads in developing countries, little is known about their benefits. This paper derives an expression for the willingness-to-pay for a reduction in transport costs from the canonical agricultural household model and uses it to estimate the benefits of a hypothetical road project. Estimation is based on novel cross-sectional data collected in a small region of Madagascar with enormous, yet plausibly exogenous, variation in transport cost. A road that essentially eliminated transport costs in the study area would boost the incomes of the remotest households-those facing transport costs of about USD 75/ton-by nearly half, mostly by raising non-farm earnings. This benefit estimate is contrasted to one based on a hedonic approach.

Transport as a Factor in the Investment Climate

Aoki, Naomi; Roberts, Peter
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
36.02%
This Note shows how, through a process of consultation between the World Bank Transport Sector and Private Sector Department, some focus on transport has been introduced into the Global "core" module of the Investment Climate Survey. The Note also shows the scope for achieving much more focus on specific transport constraints in Investment Climate Assessments for countries where these are expected to be particularly important. Examples are given of questionnaires which have been developed to complement the "core" module and specifically to meet the needs of two Regions, Africa and Latin America and the Caribbean, where different aspects of transport have been identified as significant considerations for investors. For Africa the focus is on the availability of suitable transport services. For Latin America the emphasis is rather on the role of transport in influencing the location of enterprises. Application of these revised questionnaires will provide more data on the contribution of transport to doing business in different countries.

Notes on the Economic Evaluation of Transport Projects

Mackie, Peter; Nellthorp, John; Laird, James
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
36.01%
In response to many requests for help in the application of both conventional cost benefit analysis in transport and addressing of the newer topics of interest, we have prepared a series of Economic Evaluation Notes that provide guidance on some of issues that have proven more difficult to deal with. The Economic Evaluation Notes are arranged in three groups. The first group (TRN-6 to TRN-10) provides criteria for selection a particular evaluation technique or approach; the second (TRN-11 to TRN-17) addresses the selection of values of various inputs to the evaluation, and the third (TRN-18 to TRN-26) deals with specific problematic issues in economic evaluation. The Notes are preceded by a Framework (TRN-5), that provides the context within which we use economic evaluation in the transport sector. Economic evaluation involves the assessment of the net value of projects and policies. In the transport sector we value projects in terms of their net worth, the difference between the value of their benefits and their costs...

A National Framework for Sustainable Urban Transport Systems : Proposals for Improving Urban Transportation in Russian Cities

World Bank
Fonte: World Bank, Moscow Publicador: World Bank, Moscow
EN_US
Relevância na Pesquisa
36.03%
In many Russian cities, these growing demands for mobility are not adequately met by the existing urban transport infrastructure and services. Most municipalities have had difficulties in planning and managing the development of their urban transport systems in a coherent manner, which is a precondition for successful resolution of the existing transport problems. In addition, there is a need to develop and put in place a sound legal and regulatory framework. Thus, in order to create favorable conditions for addressing the existing transport problems, there is a need to develop a national framework that would contribute to the creation of pre-requisites for sustainable development of urban transport systems. The purpose of this work is to develop proposals for the formation of the national framework for improvement of the quality and sustainability of urban transport and road traffic safety in Russian cities.

Mainstreaming Gender in Road Transport : Operational Guidance for World Bank Staff

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
36.03%
The paper aims to provide guidance for both transport and gender specialists on how to mainstream gender-related considerations into road transport projects to improve development effectiveness, sustainability and to reduce gender inequality. The paper draws attention to the most basic ways in which gender affects and is affected by transport policies and projects and provides practical approaches to address gender-related problems in road transport projects. Women and men have different travel and transport needs due to their different social and economic roles and activities. Women also face different constraints than men in accessing, using and paying for transport services. Transport can play a significant role in ameliorating or exacerbating the life conditions of women, particularly when poor and living in developing countries, depending on the extent to which gender differences are taken into account. The paper provides examples of entry points for mainstreaming gender into various road project contexts in urban...

A Framework for Urban Transport Projects : Operational Guidance for World Bank Staff

Mitric, Slobodan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
36.03%
This paper starts with a brief perspective on urban transport in developing countries, followed by a detailed presentation of an overall framework for making projects in this sector. Additional details on cities and projects used as case studies are given in the accompanying tables. The challenge for the Bank is to assist client cities in providing transport infrastructure and services that respond to demographic, spatial and economic growth in ways that balance the many different competing interests. Reflecting the importance that poverty and environmental factors are given in its development lending, the key strategic goal of the Bank is to protect and nurture public transport services and non-motorized transport modes, with underlying meta-objectives of equity and sustainability. In the policy dimension, the following approach features: (i) the equitable allocation of existing/new street space to protect and nurture public transport, and non-motorized modes; (ii) a for-the market rather than in the market...

Improving Accessibility to Transport for People with Limited Mobility : A Practical Guidance Note

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
36.02%
This document aims to provide practical guidance on how best to include consideration of accessibility for People with Limited Mobility (PLM). While disabled people are a primary focus, the definition of PLM considered within this guidance note therefore also encompasses this broader range of users with mobility constraints and needs. Barriers to addressing the needs of PLM are often a product of a lack of information for transport professionals and facility designers, combined with limited resources. To assist client countries with implementing the principles and binding obligations of the United Nations Convention on the Rights of Persons with Disabilities (UNCRPD), it is clear that World Bank Task Team Leaders (TTLs) need to understand how to build in accessibility for disabled people in the design and implementation of transport projects. This guidance note therefore aims to aid World Bank TTLs when specifying and managing Bank funded transport projects in order to improve the accessibility of transport systems for PLM. It is intended to serve primarily as a point of reference for TTLs on how to include...

Developing the Public Transport Sector in China

Gwilliam, Ken
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
36.03%
The focus of this discussion paper is on institutional arrangements for the provision of public transport bus services, including the introduction of private capital in bus operations, the value of competitive tendering mechanisms as a determining factor in selecting suppliers, and the role of regulation. The purpose of this paper is to assist Chinese municipalities by describing the experience of other countries that have attempted to implement similar reforms, which may be considered relevant to China. The goal of this paper is to assist interested municipalities, the Ministry of Construction, and other relevant Chinese authorities to: 1) identify models of regulation and competition for the urban bus industry, based on the experience of Chinese and international practices, which are best, suited for the current and projected future of the urban bus industry in China; and 2) provide guidance for municipalities that are considering restructuring their bus industries.

A Review of International Legal Instruments : Facilitation of Transport and Trade in Africa, Second Edition

de Matons, Jean Grosdidier
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
36.22%
This is the second edition of the 2003 paper entitled "Facilitation of transport and trade in Sub-Saharan Africa : a review of international legal instruments - Treaties, conventions, protocols, decisions, directives." Three major reasons motivated this update and an expansion of its scope. First, African countries are increasingly cooperating, especially in the area of corridors, to achieve full connectivity, mobility and accessibility. To that end, they are concluding new agreements and conventions. Second, this new edition has been extended to the whole of the African continent, including the Maghreb, which was not in the previous inventory. Third, air transport and associated agreements and conventions were added at the request of countries. Indeed, the future of air transport in Africa is bright. It is likely that it becomes an affordable mode of transport to reach remote areas.

Transport Policies and Development

Berg, Claudia N.; Deichmann, Uwe; Liu, Yishen; Selod, Harris
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
36.02%
This survey reviews the current state of the economic literature, assessing the impact of transport policies on growth, inclusion, and sustainability in a developing country context. The findings are summarized and methodologies are critically assessed, especially those dealing with endogeneity issues in empirical studies. The specific implementation challenges of transport policies in developing countries are discussed.

Advanced methods for structural characterization and structure-property correlation for functional materials of layered compounds

Dürrschnabel, Michael Thomas
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
Relevância na Pesquisa
36.24%
A large number of functional materials have layered structures yielding anisotropic physical properties and an exciting physics of extended defects. For the understanding of both phenomena extensive computational methods are necessary for calculating anisotropic physical properties in an ab-initio approach. Calculating high-energy electron scattering is essential to yield quantitative results on defect structures by electron microscopy and spectroscopy. In this thesis superconducting ReBa2Cu3O7-x (ReBCO, Re = rare earth) coated conductors and thermoelectric Bi2Te3-related device-relevant materials were analyzed in detail. For both compounds various computational methods were applied to yield a quantitative structure-property correlation. The microstructure and the chemical composition of a material affecting its macroscopic physical properties is referred to as structure-property correlation. Coated conductors consist of multilayer thin film structures and are high-temperature superconducting (HTS) wires of the second generation. The analyzed coated conductors were grown by two methods: (i) chemical solution deposition (CSD) and (ii) inclined substrate deposition (ISD). In this work both materials were analyzed and compared to each other...

“Governance in the Protection of Immovable Property Rights in Albania: A Continuing Challenge” : A World Bank Issue Brief - Second Edition

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Institutional and Governance Review (IGR); Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
36.04%
Despite several attempts at reform, immovable property rights in Albania are not adequately secure and represent an important governance challenge. Problems have resulted from incomplete first title registration, the lack of accurate cadastral records, and, in many cases, the absence of reliable evidence of ownership. Although Albania has adopted legislation calling for restitution or compensation for owners whose property was expropriated under communism, implementation is incomplete. In Albania, rapid internal migration has resulted in informal occupation of land and unauthorized construction on a mass scale, thus compounding the problems associated with the incomplete transfer of property. During the 1990s, as much as one-third of the population of some northern and mountainous regions migrated to urban, peri-urban, and coastal areas in search of income generation opportunities, despite the lack of adequate housing infrastructure or public service provision. Internal migration continues, albeit at a slower pace. Gaps in territorial planning legislation and administrative failures in the issuance of construction permits have made it difficult to obtain an appropriate construction permit...

World Bank Urban Transport Strategy Review : The Case of Cairo, Egypt

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Other Urban Study
ENGLISH; EN_US
Relevância na Pesquisa
36.02%
The increased density and sprawl of Cairo's urban areas are the consequence of a number of factors, of which the major ones are the physical and geographic features, transport supply, urban policy and the control of urban development, market laws, government aid, property developers, consumer sensitivity to building quality and costs, travelling distances, tariffs, the immediate surrounding area, etc. The purpose of this study is to measure the impact of a transport policy on the accessibility and development of the Cairo urban area. Cairo's transport policy has encouraged tremendous development of major road infrastructures, partial liberalization of the surface public transport network resulting in a considerable expansion of private microbus lines, and an extension of the bus network at the expense of the density of supply and of regularity, and without creating segregated lanes as recommended in successive transport and urban studies, amongst other significant developments. This report explores the influence of transport on the development of urban areas...

Poland - Public Land and Property Asset Management in Warsaw : Strategic Opportunities

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Policy Note; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
36.01%
The report is addressed to two audiences: the World Bank team and the decision makers and technical experts at the city administration who define the future of land and asset management in Warsaw. The report starts (section two) from reviewing municipal property holdings and associated institutional arrangements. This section focuses primarily on land and financial aspects of asset management, due to the overall orientation of the report and its limited scope. Portfolios of built-up properties are considered only partly, mainly for indicating the grand magnitude of the total holdings. For the same reason, the institutional arrangements are analyzed only at the level that identify main issues, but not details. Section three reviews main achievements, challenges, and risks related to municipal land and asset management in Warsaw. Section four considers the experiences of Warsaw with public-private partnerships (PPPs) in the past and on city's plans. This section also includes a discussion of a PPP potential related to such transportation facilities as Park and Ride (P&R)...

Characterizing the transplanar and in-plane water transport of textiles with gravimetric and image analysis technique: Spontaneous Uptake Water Transport Tester

Tang, K. P. M.; Wu, Y. S.; Chau, K. H.; Kan, C. W.; Fan, J. T.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 15/04/2015 EN
Relevância na Pesquisa
36.02%
Water absorption and transport property of textiles is important since it affects wear comfort, efficiency of treatment and functionality of product. This paper introduces an accurate and reliable measurement tester, which is based on gravimetric and image analysis technique, for characterising the transplanar and in-plane wicking property of fabrics. The uniqueness of this instrument is that it is able to directly measure the water absorption amount in real-time, monitor the direction of water transport and estimate the amount of water left on skin when sweating. Throughout the experiment, water supply is continuous which simulates profuse sweating. Testing automation could even minimise variation caused by subjective manipulation, thus enhancing testing accuracy. This instrument is versatile in terms of the fabrics could be tested. A series of shirting fabrics made by different fabric structure and yarn were investigated and the results show that the proposed method has high sensitivity in differentiating fabrics with varying geometrical differences. Fabrics with known hydrophobicity were additionally tested to examine the sensitivity of the instrument. This instrument also demonstrates the flexibility to test on high performance moisture management fabrics and these fabrics were found to have excellent transplanar and in-plane wicking properties.

Reading charge transport from spin dynamics on the surface of topological insulator

Liu, Xin; Sinova, Jairo
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.05%
Resolving the conductance of the topological surface states (TSSs) from the bulk contribution has been a great challenge for studying the transport property of topological insulators. By developing a non-purturbative diffusion equation that describes fully the spin-charge dynamics in the strong spin-orbit coupling regime, we present a proposal to read the charge transport information of TSSs from its spin dynamics which can be isolated from the bulk contribution by time-resolved second harmonic generation pump-probe measurement. We demonstrate the qualitatively different Dyaknov-Perel spin relaxation behavior between the TSSs and the two-dimensional spin-orbit coupling electron gas. The decay time of both in-plane and out-of-plane spin polarization is naturally proved to be identical to the charge transport time. The out-of-plane spin dynamics is shown to be in the experimentally reachable regime of the femtosecond pump probe spectroscopy and thereby we suggest experiments to detect the charge transport property of the TSSs from their unique spin dynamics.; Comment: 5 pages, 2 figures + Supplementary Material; Accepted by Physical Review Letters

Impact of Calcium on Transport Property of Graphene

Katoch, Jyoti; Ishigami, Masa
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/12/2011
Relevância na Pesquisa
45.98%
We have measured the impact of calcium adsorbates on the transport property of graphene. Although calcium renders conductivity linearly dependent on the carrier density of graphene as predicted, our experimental results diverge from the existing theoretical calculations. Our data expose the inadequacy of any existing theory to describe the minimum conductivity of graphene and indicate that a more complete testing of the impurity scattering calculations will require improving the experimental capabilities by minimizing the contribution from the substrate-bound charged impurities and developing an ability to count the number of adsorbates while measuring transport.; Comment: 8 pages, 5 figures

Impact of the Gautrain on property development around station precincts

Mushongahande,R; Cloete,C E; Venter,C J
Fonte: Journal of the South African Institution of Civil Engineering Publicador: Journal of the South African Institution of Civil Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
36.18%
The paper assesses the impact of the recently completed Gautrain Rapid Rail link in Gauteng on property development in the vicinity of stations along the route. Our particular interest is in examining the extent to which the Gautrain, as a major public transport investment, has managed to stimulate and support the creation of Transit-Oriented Development (TOD) by leveraging private sector action, with the ultimate aim of moving towards more sustainable land use / transport environments. Data sources include property development records, aerial photographs and municipal zoning applications for the areas surrounding the Pretoria, Midrand, and Rosebank stations for the period 2000 to 2011, and interviews with officials and private property developers. The research found evidence of accelerated property development and increasing mixed use in all three station precincts, but significant variation in the extent to which TOD principles have been applied. Property developers considered the Gautrain to be a major factor attracting them to develop in station precincts, suggesting that the locational benefits offered by a high-quality public transport system are also present locally. However, when comparing the vibrant Rosebank with the slower-growing Pretoria and Midrand precincts...