Reflection of matter waves in potential structures

In this paper the behavior of matter waves in suddenly terminated potential structures is investigated numerically. It is shown that there is no difference between a fully quantum mechanical treatment and a semiclassical one with regards to energy redistribution. For the quantum case it is demonstrated that there can be substantial reflection at the termination. The neglect of backscattering by the semiclassical method brings about major differences in the case of low kinetic energies. A simple phenomenological model is shown to partially explain the observed backscattering using dynamics of reduced dimensionality.

Adiabatic propagation in potential structures

In this work the adiabatic approximation is applied to the propagation of matter waves in confined geometries like those experimentally realized in recent atom optical experiments. Adiabatic propagation along a channel is assumed not to mix the various transverse modes. Nonadiabatic corrections arise from the potential squeezing and bending. Here we investigate the effect of the former. Detailed calculations of two-dimensional propagation are carried out both exactly and in an adiabatic approximation. This offers the possibility to analyze the validity of adiabaticity criteria. A semiclassical (sc) approach, based on the sc Massey parameter is shown to be inadequate, and the diffraction due to wave effects must be included separately. This brings in the Fresnel parameter well known from optical systems. Using these two parameters, we have an adequate understanding of adiabaticity on the system analyzed. Thus quantum adiabaticity must also take cognizance of the intrinsic diffraction of matter waves.

Real time video segmentation for recognising paint marks on bad wooden railway sleepers

Wooden railway sleeper inspections in Sweden are currently performed manually by a human operator; such inspections are based on visual analysis. Machine vision based approach has been done to emulate the visual abilities of human operator to enable automation of the process. Through this process bad sleepers are identified, and a spot is marked on it with specific color (blue in the current case) on the rail so that the maintenance operators are able to identify the spot and replace the sleeper. The motive of this thesis is to help the operators to identify those sleepers which are marked by color (spots), using an ���Intelligent Vehicle��� which is capable of running on the track. Capturing video while running on the track and segmenting the object of interest (spot) through this vehicle; we can automate this work and minimize the human intuitions. The video acquisition process depends on camera position and source light to obtain fine brightness in acquisition, we have tested 4 different types of combinations (camera position and source light) here to record the video and test the validity of proposed method. A sequence of real time rail frames are extracted from these videos and further processing (depending upon the data acquisition process) is done to identify the spots. After identification of spot each frame is divided in to 9 regions to know the particular region where the spot lies to avoid overlapping with noise, and so on. The proposed method will generate the information regarding in which region the spot lies, based on nine regions in each frame. From the generated results we have made some classification regarding data collection techniques, efficiency, time and speed. In this report, extensive experiments using image sequences from particular camera are reported and the experiments were done using intelligent vehicle as well as test vehicle and the results shows that we have achieved 95% success in identifying the spots when we use video as it is, in other method were we can skip some frames in pre-processing to increase the speed of video but the segmentation results we reduced to 85% and the time was very less compared to previous one. This shows the validity of proposed method in identification of spots lying on wooden railway sleepers where we can compromise between time and efficiency to get the desired result.

Effect Of Different Hydrological Model Structures On The Assimilation Of Distributed Uncertain Observations

The reliable evaluation of the flood forecasting is a crucial problem for assessing flood risk and consequent damages. Different hydrological models (distributed, semi-distributed or lumped) have been proposed in order to deal with this issue. The choice of the proper model structure has been investigated by many authors and it is one of the main sources of uncertainty for a correct evaluation of the outflow hydrograph. In addition, the recent increasing of data availability makes possible to update hydrological models as response of real-time observations. For these reasons, the aim of this work it is to evaluate the effect of different structure of a semi-distributed hydrological model in the assimilation of distributed uncertain discharge observations. The study was applied to the Bacchiglione catchment, located in Italy. The first methodological step was to divide the basin in different sub-basins according to topographic characteristics. Secondly, two different structures of the semi-distributed hydrological model were implemented in order to estimate the outflow hydrograph. Then, synthetic observations of uncertain value of discharge were generated, as a function of the observed and simulated value of flow at the basin outlet, and assimilated in the semi-distributed models using a Kalman Filter. Finally, different spatial patterns of sensors location were assumed to update the model state as response of the uncertain discharge observations. The results of this work pointed out that, overall, the assimilation of uncertain observations can improve the hydrologic model performance. In particular, it was found that the model structure is an important factor, of difficult characterization, since can induce different forecasts in terms of outflow discharge. This study is partly supported by the FP7 EU Project WeSenseIt.

Public policies impacts on Latin American labor structures, preparing for integration

One of the Main Subjects to Be Discussed, in Order to Adjust Latin American Economies to a Regional Integration Network, as Imposed By Mercosul or Other Economic Common Markets, is Related to the Employment and Other Labor Markets Public Policies. the Question to Be Posed Is: Having in Mind the Characteristics of Different Labor Markets and Labor Forces, What are the Impacts of Governmental Measures Presented in the Diverse Economic Conditions of Those Countries. Having in Mind These Impacts, This Paper Aims to Examine the Requisites to Adjust the Labor Structure Standards of Latin American Countries and What Would Be the Reforms to Be Performed By These Countries in Order to Prepare These Markets and Labor Forces to Adapt to Regional Integration Networks Represented By Mercosul, Alca or Other Common Markets. There are Evaluated the Impacts of the Globalization Process, Economic Stabilization and Reform Policies Undertaken By Some Selected Latin American Countries Since the Eighties on the Labor Structure Standards, Considering the Specific Adjustment Measures to Cope With the Negative Effects of These Policies. Next, Some Cases of Europe Union (Eu) Countries Measures to Prepare to Integration is Examined, in Order to Provide Some Elements to Better Understand the Possibilities to Handle With the Extensive Changes in External Conditions. in Sequence Some Statistical Indicatives of the Impacts of These Measures on the Occupational Structuring are Analyzed For a Group of Selected Latin American and Eu Countries.

The influence of urban structures on entrepreneurial decision-making: a comparative analysis of Mexico City and S��o Paulo

Promover a atividade empreendedora �� hoje mais do que nunca uma prioridade para as economias em desenvolvimento. Em diferentes partes do mundo, empreendedores t��m sido reconhecidos como verdadeiros agentes de transforma����o, e as novas empresas que eles criam tornam-se condutoras de inova����o, que ao final pode ser difundida ao resto da economia. Teorias de economia urbana, que analisam a din��mica da rela����o entre aglomera����o urbana e atividade econ��mica, enfatizam a import��ncia da concentra����o espacial das ind��strias num mesmo setor industrial. Entender os incentivos que d��o in��cio �� atividade empreendedora �� algo novo e o foco desses estudos tem sido principalmente em alguns poucos casos de economias industrializadas. N��o obstante, o sucesso de um punhado de clusters de alta tecnologia, como o Vale do Sil��cio, por exemplo, na Calif��rnia, Estados Unidos, n��o pode ser replicado, e as condi����es locais devem ser consideradas a fim de entender a surgimento desses ecossistemas. Este estudo pretende investigar os crit��rios em que os empreendedores fundamentam suas decis��es quando selecionam as localiza����es do seu neg��cio. Especificamente, a pesquisa explora o recente movimento dos ecossistemas de empreendedores na Cidade do M��xico e em S��o Paulo, as duas maiores ��reas metropolitanas da Am��rica Latina, �� luz das teorias de economia urbana. A fim de chegar aos resultados, a pesquisa segue o m��todo baseado sobre uma an��lise comparativa de estudo de casos em dois bairros: Vila Leopoldina em S��o Paulo e a Col��nia Roma Norte na Cidade do M��xico. Os resultados consolidados baseados em entrevistas qualitativas realizadas nos dois bairros revelam que o lugar/sitio urbano, definido em termos de la��os locais assim como da atmosfera geral do ambiente, continua sendo importante para os atores apesar das comunica����es de alta velocidade que produzem mais intera����es entre as regi��es do mundo. Al��m disso, a rela����o entre o empreendedor e o seu entorno �� altamente dependente do est��gio de desenvolvimento e da natureza da atividade da empresa; redes informais revelam-se essenciais para identificar as oportunidades de neg��cio antes de serem progressivamente substitu��das por rela����es institu��das com fundos de capital de risco ou incubadoras. Estes dois ecossistemas nascentes geram suas pr��prias caracter��sticas, o que j�� pode sugerir suas futuras evolu����es.

Electoral institutions,cleavage structures,and the number of parties

Theory: A classic question in political science concems ",hat deteImines the number of parties that compete in a given polity. Broadly speaking, there are two approaches to answering this question, one that emphasizes the role of electorallaws in structuring coalitional incentives, another that emphasizes the importance of pre-existing social cleavages. In tbis paper, we view the number of parties as a product of the interaction between these two forces, following Powell (1982) and Ordeshook and Shvetsova (1994). Hypotheses: The effective number of parties in a polity should be a multiplicative rather than an additive function ofthe peImissiveness ofthe electoral system and the heterogeneity ofthe society. Methods: Multiple regression on cross-sectional aggregate electoral statistics. Unlike previous studies, we (1) do not confine attention to developed democracies; (2) explicitly control for the influence of presidential elections, taking account of whether they are concurrent or nonconcurrent, and ofthe effective number ofpresidential candidates; and (3) also control for the presence and operation of upper tiers in legislative elections. Results: The hypothesis is confiImed, both as regards the number of legislative and the number of presidential parties .