855 resultados para travel cost method
Resumo:
Professionals who are responsible for coastal environmental and natural resource planning and management have a need to become conversant with new concepts designed to provide quantitative measures of the environmental benefits of natural resources. These amenities range from beaches to wetlands to clean water and other assets that normally are not bought and sold in everyday markets. At all levels of government — from federal agencies to townships and counties — decisionmakers are being asked to account for the costs and benefits of proposed actions. To non-specialists, the tools of professional economists are often poorly understood and sometimes inappropriate for the problem at hand. This handbook is intended to bridge this gap. The most widely used organizing tool for dealing with natural and environmental resource choices is benefit-cost analysis — it offers a convenient way to carefully identify and array, quantitatively if possible, the major costs, benefits, and consequences of a proposed policy or regulation. The major strength of benefit-cost analysis is not necessarily the predicted outcome, which depends upon assumptions and techniques, but the process itself, which forces an approach to decision-making that is based largely on rigorous and quantitative reasoning. However, a major shortfall of benefit-cost analysis has been the difficulty of quantifying both benefits and costs of actions that impact environmental assets not normally, nor even regularly, bought and sold in markets. Failure to account for these assets, to omit them from the benefit-cost equation, could seriously bias decisionmaking, often to the detriment of the environment. Economists and other social scientists have put a great deal of effort into addressing this shortcoming by developing techniques to quantify these non-market benefits. The major focus of this handbook is on introducing and illustrating concepts of environmental valuation, among them Travel Cost models and Contingent Valuation. These concepts, combined with advances in natural sciences that allow us to better understand how changes in the natural environment influence human behavior, aim to address some of the more serious shortcomings in the application of economic analysis to natural resource and environmental management and policy analysis. Because the handbook is intended for non-economists, it addresses basic concepts of economic value such as willingness-to-pay and other tools often used in decision making such as costeffectiveness analysis, economic impact analysis, and sustainable development. A number of regionally oriented case studies are included to illustrate the practical application of these concepts and techniques.
Resumo:
Professionals who are responsible for coastal environmental and natural resource planning and management have a need to become conversant with new concepts designed to provide quantitative measures of the environmental benefits of natural resources. These amenities range from beaches to wetlands to clean water and other assets that normally are not bought and sold in everyday markets. At all levels of government — from federal agencies to townships and counties — decisionmakers are being asked to account for the costs and benefits of proposed actions. To non-specialists, the tools of professional economists are often poorly understood and sometimes inappropriate for the problem at hand. This handbook is intended to bridge this gap. The most widely used organizing tool for dealing with natural and environmental resource choices is benefit-cost analysis — it offers a convenient way to carefully identify and array, quantitatively if possible, the major costs, benefits, and consequences of a proposed policy or regulation. The major strength of benefit-cost analysis is not necessarily the predicted outcome, which depends upon assumptions and techniques, but the process itself, which forces an approach to decision-making that is based largely on rigorous and quantitative reasoning. However, a major shortfall of benefit-cost analysis has been the difficulty of quantifying both benefits and costs of actions that impact environmental assets not normally, nor even regularly, bought and sold in markets. Failure to account for these assets, to omit them from the benefit-cost equation, could seriously bias decisionmaking, often to the detriment of the environment. Economists and other social scientists have put a great deal of effort into addressing this shortcoming by developing techniques to quantify these non-market benefits. The major focus of this handbook is on introducing and illustrating concepts of environmental valuation, among them Travel Cost models and Contingent Valuation. These concepts, combined with advances in natural sciences that allow us to better understand how changes in the natural environment influence human behavior, aim to address some of the more serious shortcomings in the application of economic analysis to natural resource and environmental management and policy analysis. Because the handbook is intended for non-economists, it addresses basic concepts of economic value such as willingness-to-pay and other tools often used in decision making such as costeffectiveness analysis, economic impact analysis, and sustainable development. A number of regionally oriented case studies are included to illustrate the practical application of these concepts and techniques.
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This paper gives a brief review of R&D researches for light olefin synthesis directly and indirectly from synthesis gas in the Dalian Institute of Chemical Physics (DICP). The first pilot plant test was on methanol to olefin (MTO) reaction and was finished in 1993, which was based on ZSM-5-type catalyst and fixed bed reaction. In the meantime, a new indirect method designated as SDTO (syngas via dimethylether to olefin) was proposed. In this process, metal-acid bifunctional catalyst was applied for synthesis gas to dimethylether(DME) reaction, and modified SAPO-34 catalyst that was synthesized by a new low-cost method with optimal crystal size was used to convert DME to light olefin on a fluidized bed reactor. The pilot plant test on SDTO was performed and finished in 1995. Evaluation of the pilot plant data showed that 190-200 g of DME were yielded by single-pass for each standard cubic meter of synthesis gas. For the second reaction, 1.880 tons of DME or 2.615 tons of methanol produced 1 ton of light olefins, which constitutes of 0.533 ton of ethylene, 0.349 ton of propylene and 0.118 ton of butene. DICP also paid some attention on direct conversion of synthesis gas to light olefins. A semi-pilot plant test (catalyst 1.8 1) was finished in 1995 with a CO conversion > 70% and a C(2)(=)-C(4)(=) olefin selectivity 71-74% in 1000 h. (C) 2000 Published by Elsevier Science B.V. All rights reserved.
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Investment funds provide a low cost method of sharing in the rewards from capitalism. Recently “alternative investments” such as hedge funds have grown rapidly and the trading strategies open to hedge funds are now becoming available to mutual funds and even to ordinary retail investors. In this paper we analyze problems in assessing fund performance and the prospects for investment fund sectors. Choosing genuine outperformers among top funds requires a careful assessment of non-normality, order statistics and the possibility of false discoveries. The risk adjusted performance of the average hedge fund over the last 10-15 is actually not that impressive, although the “top” funds do appear to have statistically significant positive alphas.
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We demonstrate a new approach to understanding the role of fuelwood in the rural household economy by applying insights from travel cost modeling to author-compiled household survey data and meso-scale environmental statistics from Ruteng Park in Flores, Indonesia. We characterize Manggarai farming households' fuelwood collection trips as inputs into household production of the utility yielding service of cooking and heating. The number of trips taken by households depends on the shadow price of fuelwood collection or the travel cost, which is endogenous. Econometric analyses using truncated negative binomial regression models and correcting for endogeneity show that the Manggarai are 'economically rational' about fuelwood collection and access to the forests for fuelwood makes substantial contributions to household welfare. Increasing cost of forest access, wealth, use of alternative fuels, ownership of kerosene stoves, trees on farm, park staff activity, primary schools and roads, and overall development could all reduce dependence on collecting fuelwood from forests. © 2004 Cambridge University Press.
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This paper compares the Random Regret Minimization and the Random Utility Maximization models for determining recreational choice. The Random Regret approach is based on the idea that, when choosing, individuals aim to minimize their regret – regret being defined as what one experiences when a non-chosen alternative in a choice set performs better than a chosen one in relation to one or more attributes. The Random Regret paradigm, recently developed in transport economics, presents a tractable, regret-based alternative to the dominant choice paradigm based on Random Utility. Using data from a travel cost study exploring factors that influence kayakers’ site-choice decisions in the Republic of Ireland, we estimate both the traditional Random Utility multinomial logit model (RU-MNL) and the Random Regret multinomial logit model (RR-MNL) to gain more insights into site choice decisions. We further explore whether choices are driven by a utility maximization or a regret minimization paradigm by running a binary logit model to examine the likelihood of the two decision choice paradigms using site visits and respondents characteristics as explanatory variables. In addition to being one of the first studies to apply the RR-MNL to an environmental good, this paper also represents the first application of the RR-MNL to compute the Logsum to test and strengthen conclusions on welfare impacts of potential alternative policy scenarios.
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In recent years, there has been a significant increase in the number of bridges which are being instrumented and monitored on an ongoing basis. This is in part due to the introduction of bridge management systems designed to provide a high level of protection to the public and early warning if the bridge becomes unsafe. This paper investigates a novel alternative; a low-cost method consisting of the use of a vehicle fitted with accelerometers on its axles to monitor the dynamic behaviour of bridges. A simplified half-car vehicle-bridge interaction model is used in theoretical simulations to test the effectiveness of the approach in identifying the damping ratio of the bridge. The method is tested for a range of bridge spans and vehicle velocities using theoretical simulations and the influences of road roughness, initial vibratory condition of the vehicle, signal noise, modelling errors and frequency matching on the accuracy of the results are investigated.
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PURPOSE:
To evaluate reasons for non-compliance with post-cataract surgical follow-up in rural China, and assess the impact of incentives on improving compliance.
METHODS:
Patients having undergone cataract surgery more than 3 months previously at cataract surgery training hospitals in Guangdong were invited by telephone and advertisements to a hospital-based study examination, with compensation for travel costs (US$7). Information on prior post-surgical follow up was collected by questionnaire at the hospital or by telephone. Logistic regression was used to assess predictors of post-operative attendance with or without compensation.
RESULTS:
Among 518 eligible patients, 426 (82.2%) underwent interviews and 342 (66.0%) attended the compensated study examination. Ninety nine participants (23.2%) reported previously returning for uncompensated follow-up ≥ 3 months post-operatively, and 225 (52.8%) had returned for any prior post-operative examination. Uncompensated follow-up at ≥ 3 months was associated with higher income (P = 0.037), and recalling instruction by a doctor to follow-up (P = 0.001), while age, gender, travel cost, and post-operative satisfaction and vision were not associated. Younger (P = 0.002) patients and those reporting being instructed to follow up (P = 0.008) were more likely to return for the compensated research examination. Among all interviewed subjects, only 170 (39.9%) reported knowing they were to return to hospital.
CONCLUSIONS:
Modest compensation, advertisements and telephone contact can increase medium-term follow-up rates after cataract surgery by three-fold. Better communication of specific targets for follow-up may improve follow-up compliance.
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A low-cost method is proposed to classify wine and whisky samples using a disposable voltammetric electronic tongue that was fabricated using gold and copper substrates and a pattern recognition technique (Principal Component Analysis). The proposed device was successfully used to discriminate between expensive and cheap whisky samples and to detect adulteration processes using only a copper electrode. For wines, the electronic tongue was composed of copper and gold working electrodes and was able to classify three different brands of wine and to make distinctions regarding the wine type, i.e., dry red, soft red, dry white and soft white brands. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.
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The work presented in this thesis concerns the dimensioning of an Energy Storage System (ESS) which will be used as an energy buffer for a grid-connected PV plant. This ESS should help managing the PV plant to inject electricity into the grid according to the requirements of the grid System Operator. It is desired to obtain a final production not below 1300kWh/kWp with a maximum ESS budget of 0.9€/Wp. The PV plant will be sited in Martinique Island and connected to the main grid. This grid is a small one where the perturbations due clouds in the PV generation are not negligible anymore. A software simulation tool, incorporating a model for the PV-plant production, the ESS and the required injection pattern of electricity into the grid has been developed in MS Excel. This tool has been used to optimize the relevant parameters defining the ESS so that the feed-in of electricity into the grid can be controlled to fulfill the conditions given by the System Operator. The inputs used for this simulation tool are, besides the conditions given by the System Operator on the allowed injection pattern, the production data from a similar PV-plant in a close-by location, and variables for defining the ESS. The PV production data used is from a site with similar climate and weather conditions as for the site on the Martinique Island and hence gives information on the short term insolation variations as well as expected annual electricity production. The ESS capacity and the injected electric energy will be the main figures to compare while doing an economic study of the whole plant. Hence, the Net Present Value, Benefit to Cost method and Pay-back period studies are carried on as dependent of the ESS capacity. The conclusion of this work is that it is possible to obtain the requested injection pattern by using an ESS. The design of the ESS can be made within an acceptable budget. The capacity of ESS to link with the PV system depends on the priorities of the final output characteristics, and it also depends on which economic parameter that is chosen as a priority.
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GPS technology has been embedded into portable, low-cost electronic devices nowadays to track the movements of mobile objects. This implication has greatly impacted the transportation field by creating a novel and rich source of traffic data on the road network. Although the promise offered by GPS devices to overcome problems like underreporting, respondent fatigue, inaccuracies and other human errors in data collection is significant; the technology is still relatively new that it raises many issues for potential users. These issues tend to revolve around the following areas: reliability, data processing and the related application. This thesis aims to study the GPS tracking form the methodological, technical and practical aspects. It first evaluates the reliability of GPS based traffic data based on data from an experiment containing three different traffic modes (car, bike and bus) traveling along the road network. It then outline the general procedure for processing GPS tracking data and discuss related issues that are uncovered by using real-world GPS tracking data of 316 cars. Thirdly, it investigates the influence of road network density in finding optimal location for enhancing travel efficiency and decreasing travel cost. The results show that the geographical positioning is reliable. Velocity is slightly underestimated, whereas altitude measurements are unreliable.Post processing techniques with auxiliary information is found necessary and important when solving the inaccuracy of GPS data. The densities of the road network influence the finding of optimal locations. The influence will stabilize at a certain level and do not deteriorate when the node density is higher.
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Com a globalização do mercado e o alto nível de competitividade no setor educacional, as organizações, para manterem-se, devem ser ágeis e competentes. Neste contexto, a gestão eficiente dos recursos e a obtenção de informações precisas que apóiem a tomada de decisão dependerão, em grande parte, de um sistema de informações de custos. Este sistema deverá ter como base um método de custeio que forneça informações, a fim de atender as distintas necessidades dos gestores dos diversos níveis hierárquico e das diversas áreas de atuação. O trabalho consiste no estudo de uma metodologia de custeio aplicável a uma Instituição de Ensino Superior – IES privada, a qual atenda as três perspectivas que são fornecer informações para embasar a composição dos preços, para apoiar o processo decisório e para o planejamento e controle de gastos. Para tanto, partiu-se da pesquisa bibliográfica no levantamento do estado da arte relacionada ao tema. Com o estudo de caso buscou-se a identificação das necessidades de informações de custos, demandadas pelos gestores da IES, por meio de pesquisa qualitativa. A partir dessa identificação, as necessidades foram cruzadas com os métodos de custeio existentes, o que permitiu a identificação do método mais adequado a IES. Nesta etapa foi possível o cruzamento entre a teoria e a prática, onde foram comparados o método proposto em relação ao atual método adotado pela IES o que possibilitou a identificação das deficiências do modelo atual e suas causas. A partir disto, propõe-se uma sistemática mais adequada para apoiar a tomada de decisão, com o intuito de melhoria do desempenho da instituição. Os resultados obtidos demonstram o cumprimento do objetivo onde, considerando as necessidades de informações de custos dos gestores, o método de custeio por atividades é o mais adequado para o suporte a gestão da IES.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Iron nitrite films, with hundred of nanometers thick, were deposited using the Cathodic cage plasma nitriding method, with a N2/H2 plasma, over a common glass substract. The structure, surface morphology and magnetic properties were investigated using X-ray diffractometry (XRD), atomic force microscopy (AFM) and vibrating sample magnetometer (VSM). XRD shows the formation of γ FeN phase and a combination of ζFe2N + ɛFe3N phases. The film s saturation magnetization and coercivity depends on morphology, composition, grain size and treatment temperature. Temperature raising from 250 ºC to 350 ºC were followed by an increase in saturation magnetization and film s surface coercivity on the parallel direction in relative proportion. This fact can be attributed to the grain sizes and to the different phases formed, since iron rich fases, like the ɛFe3N phase, emerges more frequently on more elevated treatment s temperature. Using this new and reasonably low cost method, it was possible to deposit films with both good adhesion and good magnetic properties, with wide application in magnetic devices
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Nanostructured materials have been spreading successfully over past years due its size and unusual properties, resulting in an exponential growth of research activities devoted to nanoscience and nanotechnology, which has stimulated the search for different methods to control main properties of nanomaterials and make them suitable for applications with high added value. In the late 90 s an alternative and low cost method was proposed from alkaline hydrothermal synthesis of nanotubes. Based on this context, the objective of this work was to prepare different materials based on TiO2 anatase using hydrothermal synthesis method proposed by Kasuga and submit them to an acid wash treatment, in order to check the structural behavior of final samples. They were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), adsorption/desorption of N2, thermal analysis (TG/DTA) and various spectroscopic methods such as absorption spectroscopy in the infrared (FT-IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). All the information of characterizations confirmed the complete conversion of anatase TiO2 in nanotubes titanates (TTNT). Observing the influence of acid washing treatment in titanates structure, it was concluded that the nanotubes are formed during heat treatment, the sample which was not subjected to this process also achieved a complete phase transformation, as showed in crystallography and morphology results, however the surface area of them practically doubled after the acid washing. By spectroscopy was performed a discussion about chemical composition of these titanates, obtaining relevant results. Finally, it was observed that the products obtained in this work are potential materials for various applications in adsorption, catalysis and photocatalysis, showing great promise in CO2 capture