Herramienta funcional para desarrollo y manejo de un modelo de gestión de inventarios

Esta tesis surge como una oportunidad de crear una herramienta de mejora en las empresas, para controlar los inventarios de la manera más adecuada. Debido a los desórdenes de los precios en el mercado, las promociones no planeadas, y la confrontación de pronósticos optimistas Vs. Pronósticos conservadores, se presenta un gran volumen de devoluciones, repercutiendo en el deterioro de la cartera y afectando directamente las metas estratégicas de las empresas. Tras esta clara oportunidad de mejora, se toma la decisión de evaluar el modelo de pronóstico que arroje los valores más acertados para la planeación de la demanda. Por otro lado, se analizo el mejor modelo de inventarios con sus respectivos indicadores de control. Dando como resultado una herramienta parametrizada en Excel, que arroja datos de pronósticos de ventas más acertados y optimiza la gestión de los inventarios. Esta herramienta contiene un modelo de gestión de inventarios de revisión continua, lo cual brinda información más acertada de la demanda que enfrenta la compañía, las ventas que puede generar, y los procesos que necesita planear para respaldar su actividad.

Neural networks of human nature and nurture

Neural network methods have facilitated the unification of several unfortunate splits in psychology, including nature versus nurture. We review the contributions of this methodology and then discuss tentative network theories of caring behavior, of uncaring behavior, and of how the frontal lobes are involved in the choices between them. The implications of our theory are optimistic about the prospects of society to encourage the human potential for caring. 

A atitude dos professores em relação às vantagens da educação inclusiva

À medida que a escola pretende cada vez mais inserir no seu seio todos os alunos, independentemente das suas características e necessidades, coloca-se um grande desafio para as instituições escolares: educar estes alunos de forma adequada. Nos últimos anos, o conceito de Inclusão foi sofrendo uma grande evolução, tendo como principio fulcral o ajuste das necessidades de aprendizagem e adaptação das perspectivas de ensino, às dificuldades dos indivíduos. A adopção de uma filosofia inclusiva tende assim, uma reestruturação da própria escola e revoga uma acção e atitude em prol dos direitos humanos e dos cidadãos. O objectivo deste estudo passa então por investigar as atitudes dos professores em relação às vantagens da educação inclusiva, quer em relação aos alunos ditos normais, quer com deficiência, e perceber de que formas essas atitudes são influenciáveis, tendo em conta o género dos docentes, e de que modo o contacto com pessoas com deficiência na infância/juventude influencia positivamente a atitude dos mesmos. O estudo foi realizado com uma amostra de 741 professores (N= 535 do género feminino e N= 206 do género masculino). Foi aplicado o questionário APIAD – A Atitude dos Professores face à Inclusão de Alunos com Deficiência (Leitão, 2011). A análise dos resultados obtidos permitiu-nos concluir que os professores que tiveram na sua infância/juventude contacto com pessoas com deficiência têm uma atitude mais favorável relativamente às vantagens da inclusão para os alunos com deficiência (p≤0,10). Relativamente ao Género dos docentes, as professoras têm uma atitude mais favorável relativamente às vantagens da inclusão do que os professores (p = 0,023). Quanto às vantagens da inclusão para os alunos normais e alunos com deficiência, os resultados mantêm-se, com uma atitude mais favorável por parte das professoras relativamente ao professores, sendo as diferenças estatisticamente significativas (p = 0,017.) e (p ≤ 0,10).ABSTRACT: While school aims at increasing the inclusion of its students, regardless of their specific characteristics or needs, there is a greater challenge for the institutions: that of educating its students adequately. In the last few years, the concept of inclusion has developed, having as its core value the adjustment of needs and the integration of teaching propositions in relation to students. The adoption of an inclusive philosophy tends, thus, to restructure the school itself and revokes certain actions and attitudes in accordance to human rights. One of the aims of this study includes the investigation of the attitudes of teachers regarding the advantages of inclusion in education, whether towards students said normal or those with a disability. Another aim is to understand how these attitudes can be influenced, taking into account the gender of faculty members and how the contact with people with disabilities in childhood/teenage years may have a positive influence in the attitudes of teachers. The study was carried out with a sample of 741 teachers (N= 535 females and N= 206 males). We used the APIAD questionnaire - A Atitude dos Professores face à Inclusão de Alunos com Deficiência/Teacher‟s Attitudes towards the Inclusion of Disabled Students (Leitão, 2011) The collected data helped us conclude that teachers who had contact with disabled people during their childhood/teenage years have a more positive attitude towards the advantages of inclusion. (p 0,10). Regarding the gender of faculty members, female teachers have a more positive attitude in relation to said advantages than male teachers (p= 0,023). As for the advantages of inclusion towards „normal‟ children and those who are disabled, the results are the same: female teachers have a more optimistic attitude than male teachers. The differences are statistically significant (p = 0.017) and (p  0,10).

A restauração nos transportes turísticos : o catering no comboio TGV europeu : projecto de empresa para explorar o catering do TGV em Portugal

Este projecto apresenta-se em três capítulos, antecedida da introdução onde serão apresentadas as questões teóricas, metodológicas e conceptuais. No primeiro capítulo faremos um enquadramento dos conceitos relacionados com o transporte turístico, em particular o ferroviário, onde serão focalizados a estratégia e competitividade, a gastronomia, a restauração, bem como catering. No segundo capítulo faremos a análise do catering do TGV europeu, analisando os serviços de catering de cada TGV, examinaremos a importância das linhas TGV para o futuro do turismo no espaço europeu, bem como esboçaremos um indicador de atractividade potencial do catering a bordo do TGV. No terceiro capítulo concentraremos o foco na concepção de um projecto empresarial para a exploração do catering a bordo do TGV para ligação de Lisboa a Madrid, tendo por base as previsões de passageiros anunciadas pela RAVE, projectando receitas e despesas potenciais para os próximos cinco anos, respeitando os indicadores de gestão para o sector, com base em três cenários (realista, optimista e pessimista). Finalmente, inferiremos se a empresa apresentará potencial para ser viável ou inviável do ponto de vista operacional e financeiro, com base nas opções tomadas ao longo do projecto de dissertação.

Ao encontro da inclusão: Uma tentativa de promover a autonomia e o sucesso de uma aluna com autismo, na disciplina de Matemática, através de estratégias de aprendizagem cooperativa

A Escola Inclusiva é a conquista recente de uma sociedade culta e democrática que vê na educação um campo de luta pelo cumprimento dos direitos à igualdade de todos os cidadãos independentemente das suas características individuais, exigindo uma escola que não discrimine e aceite a diferença. O trabalho apresentado é decorrente do Projeto de Intervenção, fundamentado na investigação-ação, realizado no âmbito do Curso de 2º ciclo em Educação Especial. Com este projeto quisemos minimizar dificuldades apresentadas por uma aluna com características do espectro do autismo, na área curricular disciplinar de Matemática e da socialização, numa perspectiva inclusiva. O enquadramento teórico abordou a Educação Inclusiva, a Escola Inclusiva, a Aprendizagem Cooperativa e as Perturbações do Espectro do Autismo. Como instrumentos, utilizámos a pesquisa documental, a entrevista semi-directiva à professora de Educação Espacial, a observação naturalista e a sociometria. A planificação global da intervenção, equacionada numa perspectiva de escola inclusiva, foi elaborada a partir do relacionamento/ cruzamento dos dados que resultaram da análise da informação recolhida, avaliados ao longo de todo o processo. A intervenção permitiu-nos constatar que a aluna fez aprendizagens significativas na área académica e social. Assim, nesta intervenção, confrontámo-nos com o desafio de práticas educativas, diferenciadas e inclusivas. Estas práticas, por sua vez, contribuíram para que os colegas e pais a olhassem de forma mais optimista e com um maior respeito face à sua problemática.

Anatomías contrariadas: la representación del cuerpo en la literatura sobre los Andes (Estudios)

La autora analiza tres textos latinoamericanos que muestran construcciones del imaginario andino, extendidas a ciertos estereotipos sobre la corporalidad andina: frágil, dolorida, para la cual la esperanza de liberación radica en un azar. En «Boletín y Elegía de las Mitas», César Dávila presenta una versión del cuerpo indio «exclusivamente centrada en la vejación de lo anatómico» (de su cabeza y genitales, de órganos tan profundos como el corazón y el esqueleto), con lo que el cuerpo desnudo y forzado se convierte en ajeno. En «El sueño del Pongo», de José María Arguedas, el cuerpo del indio oprimido es diminuto, y porta una «gestualidad comprimida que se pone en juego a partir de posturas humilladas». Pese al final aparentemente optimista de ambos textos, se trata de productos culturales que cumplen un rol en el ejercicio de control social. En «Barraquera», de José de la Cuadra, el cuerpo de esta mujer es fundado a partir de violaciones, muertes y migraciones forzadas: habituado a sufrir y callar, para este cuerpo el dolor se convierte en la única vía posible de acceso al placer. Se remarca que el tiempo cronológico de los tres relatos es el de la espera, el tiempo del destino. Para estos cuerpos-lugares siempre vulnerables y violentados, burlados o invisibilizados, lo fatal fundamentaría un cierre de lo histórico.

Age-specific survival of male Golden-cheeked Warblers on the Fort Hood Military Reservation, Texas

Population models are essential components of large-scale conservation and management plans for the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia; hereafter GCWA). However, existing models are based on vital rate estimates calculated using relatively small data sets that are now more than a decade old. We estimated more current, precise adult and juvenile apparent survival (Φ) probabilities and their associated variances for male GCWAs. In addition to providing estimates for use in population modeling, we tested hypotheses about spatial and temporal variation in Φ. We assessed whether a linear trend in Φ or a change in the overall mean Φ corresponded to an observed increase in GCWA abundance during 1992-2000 and if Φ varied among study plots. To accomplish these objectives, we analyzed long-term GCWA capture-resight data from 1992 through 2011, collected across seven study plots on the Fort Hood Military Reservation using a Cormack-Jolly-Seber model structure within program MARK. We also estimated Φ process and sampling variances using a variance-components approach. Our results did not provide evidence of site-specific variation in adult Φ on the installation. Because of a lack of data, we could not assess whether juvenile Φ varied spatially. We did not detect a strong temporal association between GCWA abundance and Φ. Mean estimates of Φ for adult and juvenile male GCWAs for all years analyzed were 0.47 with a process variance of 0.0120 and a sampling variance of 0.0113 and 0.28 with a process variance of 0.0076 and a sampling variance of 0.0149, respectively. Although juvenile Φ did not differ greatly from previous estimates, our adult Φ estimate suggests previous GCWA population models were overly optimistic with respect to adult survival. These updated Φ probabilities and their associated variances will be incorporated into new population models to assist with GCWA conservation decision making.

Sampling uncertainties in surface radiation budget calculations in RADAGAST

In the Radiative Atmospheric Divergence Using ARM Mobile Facility GERB and AMMA Stations (RADAGAST) project we calculate the divergence of radiative flux across the atmosphere by comparing fluxes measured at each end of an atmospheric column above Niamey, in the African Sahel region. The combination of broadband flux measurements from geostationary orbit and the deployment for over 12 months of a comprehensive suite of active and passive instrumentation at the surface eliminates a number of sampling issues that could otherwise affect divergence calculations of this sort. However, one sampling issue that challenges the project is the fact that the surface flux data are essentially measurements made at a point, while the top-of-atmosphere values are taken over a solid angle that corresponds to an area at the surface of some 2500 km2. Variability of cloud cover and aerosol loading in the atmosphere mean that the downwelling fluxes, even when averaged over a day, will not be an exact match to the area-averaged value over that larger area, although we might expect that it is an unbiased estimate thereof. The heterogeneity of the surface, for example, fixed variations in albedo, further means that there is a likely systematic difference in the corresponding upwelling fluxes. In this paper we characterize and quantify this spatial sampling problem. We bound the root-mean-square error in the downwelling fluxes by exploiting a second set of surface flux measurements from a site that was run in parallel with the main deployment. The differences in the two sets of fluxes lead us to an upper bound to the sampling uncertainty, and their correlation leads to another which is probably optimistic as it requires certain other conditions to be met. For the upwelling fluxes we use data products from a number of satellite instruments to characterize the relevant heterogeneities and so estimate the systematic effects that arise from the flux measurements having to be taken at a single point. The sampling uncertainties vary with the season, being higher during the monsoon period. We find that the sampling errors for the daily average flux are small for the shortwave irradiance, generally less than 5 W m−2, under relatively clear skies, but these increase to about 10 W m−2 during the monsoon. For the upwelling fluxes, again taking daily averages, systematic errors are of order 10 W m−2 as a result of albedo variability. The uncertainty on the longwave component of the surface radiation budget is smaller than that on the shortwave component, in all conditions, but a bias of 4 W m−2 is calculated to exist in the surface leaving longwave flux.

The effects of environmental perturbation and measurement error on estimates of the shape parameter in the theta-logistic model of population regulation

The theta-logistic is a widely used generalisation of the logistic model of regulated biological processes which is used in particular to model population regulation. Then the parameter theta gives the shape of the relationship between per-capita population growth rate and population size. Estimation of theta from population counts is however subject to bias, particularly when there are measurement errors. Here we identify factors disposing towards accurate estimation of theta by simulation of populations regulated according to the theta-logistic model. Factors investigated were measurement error, environmental perturbation and length of time series. Large measurement errors bias estimates of theta towards zero. Where estimated theta is close to zero, the estimated annual return rate may help resolve whether this is due to bias. Environmental perturbations help yield unbiased estimates of theta. Where environmental perturbations are large, estimates of theta are likely to be reliable even when measurement errors are also large. By contrast where the environment is relatively constant, unbiased estimates of theta can only be obtained if populations are counted precisely Our results have practical conclusions for the design of long-term population surveys. Estimation of the precision of population counts would be valuable, and could be achieved in practice by repeating counts in at least some years. Increasing the length of time series beyond ten or 20 years yields only small benefits. if populations are measured with appropriate accuracy, given the level of environmental perturbation, unbiased estimates can be obtained from relatively short censuses. These conclusions are optimistic for estimation of theta. (C) 2008 Elsevier B.V All rights reserved.

The challenges facing privatization of infrastructure projects in Libya

Libya with its strategic location and natural resources stands as a crucial link between the Arab world, Europe, and Africa. The people of Libya have an optimistic outlook with regard to the Libyan economy after the suspension of the United Nations sanctions in 1999 that had been imposed on Libya in 1992, as well as the recent emphasis on privatization from the government. Since then, local and foreign investors have been encouraged to take a more prominent role in order to help privatize some of the state run-industries; the attention to privatization is aimed to help Libya’s economic growth and reduce its heavy dependency on oil revenues. Considering the economic situation, Libya is a rich country. However, it needs to modernize, it needs more and better infrastructure, it needs non-oil based financing, furthermore, it needs to develop a financial model for development and investment from the private sector. Although the Libyan government is working on the improvement of the business environment to make it more attractive for foreign investors in a way to move towards privatization, they have ignored some of the challenges that privatization will be facing in Libya. Privatization can not be implemented overnight. They have taken this for granted without careful consideration of its challenges. This paper attempts to investigate and discuss the challenges that need to be taken into account before privatization of infrastructure projects can be introduced in Libya. This paper is based on interviews with senior technical officials in the government.

Nonlinear data assimilation in geosciences: an extremely efficient particle filter

Almost all research fields in geosciences use numerical models and observations and combine these using data-assimilation techniques. With ever-increasing resolution and complexity, the numerical models tend to be highly nonlinear and also observations become more complicated and their relation to the models more nonlinear. Standard data-assimilation techniques like (ensemble) Kalman filters and variational methods like 4D-Var rely on linearizations and are likely to fail in one way or another. Nonlinear data-assimilation techniques are available, but are only efficient for small-dimensional problems, hampered by the so-called ‘curse of dimensionality’. Here we present a fully nonlinear particle filter that can be applied to higher dimensional problems by exploiting the freedom of the proposal density inherent in particle filtering. The method is illustrated for the three-dimensional Lorenz model using three particles and the much more complex 40-dimensional Lorenz model using 20 particles. By also applying the method to the 1000-dimensional Lorenz model, again using only 20 particles, we demonstrate the strong scale-invariance of the method, leading to the optimistic conjecture that the method is applicable to realistic geophysical problems. Copyright c 2010 Royal Meteorological Society

Changing climate and the Irish landscape

The impacts of current and future changes in climate have been investigated for Irish vegetation. Warming has been observed over the last two decades, with impacts that are also strongly influenced by natural oscillations of the surrounding ocean, seen as fluctuations in the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. Satellite observations show that vegetation greenness increases in warmer years, a feature mirrored by increases in net ecosystem production observed for a grassland and a plantation forest. An ensemble of general circulation model simulations of future climates indicate temperature rises over the twenty-first century ranging from 1°C to 7°C, depending on future scenarios of greenhouse gas emissions. Net primary production is simulated to increase under all scenarios, due to the positive impacts of rising temperature, a modest rise of precipitation and rising carbon dioxide concentrations. In an optimistic scenario of reducing future emissions, CO2 concentration is simulated to flatten from about 2070, although temperatures continue to increase. Under this scenario Ireland could become a source of carbon, whereas under all other emission scenarios Ireland is a sink for carbon that may increase by up to three-fold over the twenty-first century. A likely and unavoidable impact of changing climate is the arrival of alien plant species, which may disrupt ecosystems and exert negative impacts on native biodiversity. Alien species arrive continually, with about 250 dated arrivals in the twentieth century. A simulation model indicates that this rate of alien arrival may increase by anything between two and ten times, dependent on the future climatic scenario, by 2050. Which alien species may become severely disruptive is, however, not known.

Estimating reliability and resolution of probability forecasts through decomposition of the empirical score

References (20)Cited By (1)Export CitationAboutAbstract Proper scoring rules provide a useful means to evaluate probabilistic forecasts. Independent from scoring rules, it has been argued that reliability and resolution are desirable forecast attributes. The mathematical expectation value of the score allows for a decomposition into reliability and resolution related terms, demonstrating a relationship between scoring rules and reliability/resolution. A similar decomposition holds for the empirical (i.e. sample average) score over an archive of forecast–observation pairs. This empirical decomposition though provides a too optimistic estimate of the potential score (i.e. the optimum score which could be obtained through recalibration), showing that a forecast assessment based solely on the empirical resolution and reliability terms will be misleading. The differences between the theoretical and empirical decomposition are investigated, and specific recommendations are given how to obtain better estimators of reliability and resolution in the case of the Brier and Ignorance scoring rule.

Forecasting economic and financial time series with non-linear models

In this paper we discuss the current state-of-the-art in estimating, evaluating, and selecting among non-linear forecasting models for economic and financial time series. We review theoretical and empirical issues, including predictive density, interval and point evaluation and model selection, loss functions, data-mining, and aggregation. In addition, we argue that although the evidence in favor of constructing forecasts using non-linear models is rather sparse, there is reason to be optimistic. However, much remains to be done. Finally, we outline a variety of topics for future research, and discuss a number of areas which have received considerable attention in the recent literature, but where many questions remain.

When rules and principles are not enough: insiders’ views and narratives on the global financial crisis

Much has been written about Wall Street and the global financial crisis (GFC). From a fraudulent derivatives market to a contestable culture of banking bonuses, culpability has been examined within the frames of American praxis, namely that of American exceptionalism. This study begins with an exploratory analysis of non-US voices concerning the nature of the causes of the GFC. The analysis provides glimpses of the globalized extent of assumptions shared, but not debated within the globalization convergence of financial markets as the neo-liberal project. Practical and paradigmatic tensions are revealed in the capture of a London-based set of views articulated by senior financial executives of financial service organizations, the outcomes of which are not overly optimistic for any significant change in praxis within the immediate future.