Simulated Landsat reflectance spectra of soil samples were compared to actual Landsat radiance values of soils in two fields (1 and 3) near Vance, Mississippi. The simulated reflectance spectra were calculated by combining Landsat spectral sensitivity with laboratory-based spectrophotometer reflectance values. The actual radiance data were obtained by extracting pixel values from Landsat images. Simple linear regression (SLR) yielded significant linear relationships for 1997 field-1 and 2001 field-3 data. Multiple linear regression (MLR) and weighted linear regression (WLR), which indirectly accounted for moisture content and spatial resolution, respectively, yielded improvement in R2 for most of the studied bands. The analyses generally satisfied the normality and constant variance assumptions, and removal of outliers improved the validity of the assumptions and R2. It was concluded that indirect measures of soil moisture content and spatial uncertainty can substantially improve the relationship between remotely sensed bare-soil spectra and laboratory spectra.

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Yes / Proposes the application of a genetic algorithm (GA) and simulated annealing (SA) based hybrid approach for the scheduling of generator maintenance in power systems using an integer representation. The adapted approach uses the probabilistic acceptance criterion of simulated annealing within the genetic algorithm framework. A case study is formulated in this paper as an integer programming problem using a reliability-based objective function and typical problem constraints. The implementation and performance of the solution technique are discussed. The results in this paper demonstrate that the technique is more effective than approaches based solely on genetic algorithms or solely on simulated annealing. It therefore proves to be a valid approach for the solution of generator maintenance scheduling problems

A successful business needs to generate enough cash to cover expenses, current debt, and family living expenses, pay interest on owned and borrowed capital, maintain productivity, and earn a reasonable return for the operator. Income from sheep production is generally only part of a total farm and nonfarm income. Thus options, opportunity costs, and decisions regarding the sheep production enterprise are not isolated; they affect other agricultural enterprises. Sheep production consistently returns profits to producers, which makes it an enticing agricultural enterprise. There are advantages in raising sheep in Virginia, such as abundant, high-quality forage, moderate climate, pasture improvement, and good access to markets with high demand for lamb. The disadvantages to sheep production are unavailable and inexperienced labor and operators, predators, and inconsistent market demand and supply. Sheep producers have the opportunity to choose which lambing system fits their existing operations and lifestyle. The use of economic analysis enables operator to make sound business management decisions. To compare different lambing systems (spring, fall with winter clean-up, and high-fertility fall) in a systematic way, a simulation model was constructed with a fixed forage resource of 50 acres of pasture including typical Virginia mountain pasture plus various amounts of fescue for stockpiling. The simulation included a production calendar; nutritional requirements for ewes, lambs, and artificially reared triplets; growth rates for lambs; lambing distributions; forage growth; and enterprise budgets including income, costs, and returns. A economic analysis was performed for each lambing system with average prices or with plus or minus one standard deviation for prices of corn, SBOM, and market lambs, and price differentials for market lambs across lambing seasons. Comparisons of each lambing systems produced various results. In spring lambing, only 78 ewes could be maintained on the fixed forage resource, while the fall with winter clean-up and high-fertility fall lambing system each had 115 ewes. This result occurred because of limited forage in July and August and higher nutrient requirements for spring lambing in those months. The overall nutrient requirements were higher in the fall with winter clean-up and high-fertility fall lambing than in spring lambing as a result of the increased ewe and lamb numbers. Concentrate consumption by lambs was also greater for fall with winter clean-up and high-fertility fall lambing than for spring lambing because of the increased numbers of lambs. Because of the low number of ewes and lambs, spring system produced the most hay. Labor costs were highest in fall with winter clean-up lambing because of the two lambing seasons. In the economic analysis system, each lambing was compared. With 10-year average prices for market lambs, corn, and SBOM, high-fertility fall lambing had the greatest income ($17,467), followed by fall with winter clean-up lambing ($14,695), and spring lambing ($10,358). This result occurred because high-fertility fall and fall with winter clean-up lambing had more lambs sold at higher market lambs prices than spring lambing. With 10-year average prices for market lambs, corn, and SBOM, high-fertility fall lambing had the highest cost ($7,935), followed by fall with winter clean-up lambing ($7,360), and spring lambing ($6,084). This was the result of increased ewe and lamb numbers in high-fertility fall and fall with winter clean-up lambing than spring lambing. High-fertility fall lambing had the greatest returns ($6,210), followed by fall with winter clean-up lambing ($4,025), and spring lambing ($2,028). On a fixed forage resource, increasing fertility in fall lambing clearly results in increased returns. In this model, forage availability controlled the number of ewes that a lambing system can have because of limited summer growth and had a major impact on profits. Conclusions of Tolman (1993) differed from those found within this thesis. On a per ewe basis, she found that spring lambing to yielded the highest returns whereas this thesis found that high-fertility fall lambing yielded the highest returns. A key difference between this study and that of Tolman (1993) was after weaning this thesis feed fall lambs stockpiled fescue and she feed fall lambs feed in dry lot. / Master of Science

This dissertation presents an analysis of two aspects of the chromatographic separation process known as Simulated Moving Bed (SMB) chromatography. The first aspect is system design, and the second is improving computer simulations to generate heuristics for choosing operational modes. For the past 15-20 years, there has been a surge of interest in the use of Simulated Moving Bed systems for the chromatographic separation of chemicals¹. A wide variety of methods, nomenclatures, and conventions have been adopted over the years²⁻⁴, as teams from different backgrounds adopt and improve on the SMB technology. This work presents a unifying discussion of the two major design methods, Triangle Theory and Standing Wave Design, used in the SMB field. We provide the complete computer code required to execute both design methods. A sample problem is worked, which demonstrates the novelty and ease of use that such tools provide. Mathematica was chosen for the implementation of these design methods, because of its strong symbolic analysis capabilities, and simplicity of creating interfaces for new users. We present derivations of the classic Langmuir results in Mathematica, and proceed to extend those implementations. When analytic solutions are impossible, we use Mathematica's numerical methods. This work also develops a distributed computing tool known as ChromRunner which allows large numbers of detailed numerical simulations to be run simultaneously. The motivations and benefits of this approach are discussed alongside implementation details. We apply the distributed computing system to two separate SMB separations in order to optimize them, as well as determine heuristics governing their operational modes. We wrote ChromRunner in C#, and took advantage of Visual Studio's Entity Framework to create the database backend. The user interface for this software was created using Microsoft's "Windows Presentation Foundation" (WPF) technologies. / Ph. D.

Made available in DSpace on 2016-12-23T14:33:34Z (GMT). No. of bitstreams: 1 dissertacao.pdf: 412800 bytes, checksum: 479ec97937646fdcffeadd81d19f1b7a (MD5) Previous issue date: 2006-06-01 / Computar a solução ótima para uma unidade de problema MAX-SAT Ponderado (weighted maximum satisfiability) é difícil mesmo se cada cláusula contiver apenas dois literais. Neste trabalho, será descrita a implementação de uma nova heurística aplicada a instâncias de problema do tipo MAX-SAT Ponderado, mas perfeitamente extensível a outros problemas. Para comparação, serão geradas soluções para uma quantidade significativa de problemas e seus resultados serão comparados com os de outras heurísticas já desenvolvidas para esse tipo de problema, dentre elas as heurísticas consideradas "estado da arte", ou seja, heurísticas que têm obtido os melhores resultados no universo das heurísticas existentes.

This dissertation consists of three essays that study mergers and consolidation in the Canadian cable television industry. The first essay provides a historical overview of regulatory and technical change in the industry, and presents the dataset that I constructed for this study. The basic pattern of interest in the data is regional consolidation, where dominant cable companies grow over time by acquiring the cablesystems of small cable operators. I perform a reduced-form empirical analysis that formally studies the determinants of mergers, and the effect that acquisitions have on cable bundles offered to consumers. The remaining essays develop and estimate structural econometric models to further study the determinants and welfare consequences of mergers in the industry. The second essay estimates an empirical analogue of the Farrell and Scotchmer (1988) coalition- formation game. I use the estimated model to measure the equilibrium impact that economies of scale and agglomeration has on firms’ acquisition incentives. I also study the impact entry and merger subsidies have on consolidation and long-run market structure. The final chapter estimates a variant of the Rochet and Stole (2002) model of multi-product monopoly with endogenous quality and prices. Using the estimated model I compute the impact mergers have on welfare. I find that both consumer and producer surplus rise with acquisitions. I also show that accounting for changes both in prices and products (i.e., cable bundle quality) is important for measuring the welfare impact of mergers. / Thesis (Ph.D, Economics) -- Queen's University, 2010-12-09 14:39:15.431

Submitted by Beatriz Abreu (beatrizabreu@fgvmail.br) on 2016-08-29T18:33:06Z No. of bitstreams: 1 2016_MsC_Dissertação de Beatriz Abreu Foss de Oliveira.pdf: 1421679 bytes, checksum: 27c4f7c2d081c9676080d14bdd3e2cc2 (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2016-08-30T20:08:27Z (GMT) No. of bitstreams: 1 2016_MsC_Dissertação de Beatriz Abreu Foss de Oliveira.pdf: 1421679 bytes, checksum: 27c4f7c2d081c9676080d14bdd3e2cc2 (MD5) / Approved for entry into archive by Maria Almeida (maria.socorro@fgv.br) on 2016-09-02T13:26:30Z (GMT) No. of bitstreams: 1 2016_MsC_Dissertação de Beatriz Abreu Foss de Oliveira.pdf: 1421679 bytes, checksum: 27c4f7c2d081c9676080d14bdd3e2cc2 (MD5) / Made available in DSpace on 2016-09-02T13:27:18Z (GMT). No. of bitstreams: 1 2016_MsC_Dissertação de Beatriz Abreu Foss de Oliveira.pdf: 1421679 bytes, checksum: 27c4f7c2d081c9676080d14bdd3e2cc2 (MD5) Previous issue date: 2016-05-31 / Rankings are a recent tool being used in several fields, including in management. Their pervasive use is associated to the fields of behavior and decision making. Despite their constant usage, few research have tried to define the concept of ranking and the parameters to judge whether it is acceptable. In absence of a more precise understanding of what the term ranking means, its power is diminished as well as its purpose. Thus, in this work I present the characteristics, advantages and disadvantages of rankings. Further, I analyze patterns of behavior elicited in real rankings. To this end, I propose the use of simulated annealing to study the quality of convergence of rankings’ chosen dimensions. The graphical analyses suggest, at least, two different patterns of convergence for rankings. The categories were named after well behaved and poorly behaved rankings.