Dissertations / Theses on the topic 'Trade cost'

The impact of international trade on the environment has been the field of focus since the 1970’s. There have been a number of empirical studies exploring the environmental consequence of free trade but the results are mixed and only a few environmental indicators have been used in place of the total environmental impact. In this study, I used combined environmental cost data which converted environmental impact indicators into US$ terms (the data is taken from World Bank database). Also, by taking advantage of panel data (observations from 60 countries over 25 years) and (two-way) fixed effects model, I attempted to reduce the threat of endogeneity problem. Most importantly, environmental impact which is filtered through the trade induced changes of economic activity was analyzed in parallel with unfiltered through effects. And the results revealed that trade openness reduces national level environmental cost rather than increasing it. Meanwhile, income related technique effect was found to be underperforming and when the full sample was split into four income groups, the income-environment relationship appeared to be closer to N-shape as opposed to the inverted U-shaped environmental kutznets curve hypothesis.
Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate

Les infrastructures de cloud fournissent une grande variété de ressources de calcul à la demande avec différents compromis coût-performance. Cela donne aux utilisateurs des nombreuses opportunités pour exécuter leurs applications ayant des besoins complexes en ressources, à partir d’un grand nombre de serveurs avec des interconnexions à faible latence jusqu’à des dispositifs spécialisés comme des GPUs et des FPGAs. Les besoins des utilisateurs concernant l’exécution de leurs applications peuvent varier entre une exécution la plus rapide possible, la plus chère ou un compromis entre les deux. Cependant, le choix du nombre et du type des ressources à utiliser pour obtenir le compromis coût-performance que les utilisateurs exigent constitue un défi majeur. Cette thèse propose trois contributions avec l’objectif de fournir des bons compromis coût-performance pour l’exécution des applications sur des plates-formes hétérogènes. Elles suivent deux directions : un bon usage des ressources et un bon choix des ressources. Nous proposons comme première contribution une méthode de partage pour des accélérateurs de type FPGA dans l’objectif de maximiser leur utilisation. Dans une seconde contribution, nous proposons des méthodes de profilage pour la modélisation de la demande en ressources des applications. Enfin, nous démontrons comment ces technologies peuvent être intégrées dans une plate-forme de cloud hétérogène
Cloud infrastructures provide on-demand access to a large variety of computing devices with different performance and cost. This creates many opportunities for cloud users to run applications having complex resource requirements, starting from large numbers of servers with low-latency interconnects, to specialized devices such as GPUs and FPGAs. User expectations regarding the execution of applications may vary between the fastest possible execution, the cheapest execution or any trade-off between the two extremes. However, enabling cloud users to easily make performance-cost trade-offs is not a trivial exercise and choosing the right amount and type of resources to run applications accordingto user expectations is very difficult. This thesis proposes three contributions to enable performance-cost trade-offs for application execution in heterogeneous clouds by following two directions: make good use of resources and make good choice of resources. We propose as a first contribution a method to share FPGA-based accelerators in cloud infrastructures having the objective to improve their utilization. As a second contribution we propose profiling methods to automate the selection of heterogeneous resources for executing applications under user objectives. Finally, we demonstrate how these technologies can be implemented and exploited in heterogeneous cloud platforms

This dissertation describes two essays in empirical international trade, focusing on trade costs and the pattern of trade along the intensive and extensive margins. In the first essay, I study the barriers that impede international trade. In the second paper, I examine the growth of U.S. agricultural trade in detail describing how U.S. agriculture and food trade has expanded along the margins. The first chapter introduces a relatively straightforward, yet empirically powerful, manipulation of the gravity equation. The gravity model has been dubbed the work horse model of empirical trade, and thus is a suitable foundation from which to derive an indirect measure of largely unobservable 'iceberg' trade costs. In this paper, I solve a sector level version of the gravity equation and study the pattern of agricultural trade costs and factors that impede world agricultural trade growth over a long time series, 1986-2011. In addition, I estimate sector-specific elasticity of substitution which is a key parameter in the computation of trade cost. In the second essay, I examine the growth of world and U.S. agricultural exports along the intensive and extensive margins of international trade over the period 1986 to 2010. The purpose of this essay is to decompose the growth of world and U.S. agricultural trade using qualitative methods from the marketing literature (i.e., market expansion grids) but modified to fit bilateral trade relationships and a theoretical index to measure the margins of trade at a single point in time. In addition, we examine often overlooked channels by which U.S. agricultural exports have expanded using very detailed agricultural product lines. Using information related to the pattern of a trade rather than trade volume itself, I estimate how much starting a trade relationship with a new partner or in a new product variety matters to agricultural trade growth and then conclude with a set of stylized facts to inform current theory.
Ph. D.

In project scheduling, the activity durations can often be reduced by dedicating additional resources. Time/Cost Trade-off Problem considers the compromise between the total cost and project duration. The discrete version of the problem assumes a number of time/cost pairs, so called modes, and selects a mode for each activity. In this thesis we consider the Discrete Time/Cost Trade-off Problem. We first study the Deadline Problem, i.e., the problem of minimizing total cost subject to a deadline on project duration. To solve the Deadline Problem, we propose several optimization and approximation algorithms that are based on optimal Linear Programming Relaxation solutions. We then analyze the problem of generating all efficient solutions, and propose an approach that uses the successive solutions of the Deadline Problem. Our computational results on large-sized problem instances have revealed the satisfactory behavior of our algorithms.

This master thesis considers and evaluates a few different risk models for stock portfolios, including an ordinary sample covariance matrix, factor models and an approach inspired from random matrix theory. The risk models are evaluated by simulating minimum variance portfolios and employing a cross-validation. The Bloomberg+ transaction cost model is investigated and used to optimize portfolios of stocks, with respect to a trade off between the active risk of the portfolio and transaction costs. Further a few different simulations are performed while using the optimizer to rebalance long-only portfolios. The optimization problem is solved using an active-set algorithm. A couple of approaches are shown that may be used to visually try to decide a value for the risk aversion parameter λ in the objective function of the optimization problem. The thesis concludes that there is a practical difference between the different risk models that are evaluated. The ordinary sample covariance matrix is shown to not perform as well as the other models. It also shows that more frequent rebalancing is preferable to less frequent. Further the thesis goes on to show a peculiar behavior of the optimization problem, which is that the optimizer does not rebalance all the way to 0 in simulations, even if enough time is provided, unless it is explicitly required by the constraints.

Thesis advisor: Christopher Maxwell
Though much research has been done on the subject of substituting nurse practitioners for physicians as health care providers, both analytic methods and results have been inconsistent. Various studies have shown nurse practitioners to provide equivalent or improved care especially in primary care settings. However, no consensus has been reached on whether or not and under what conditions this substitution is economically efficient. Because of variation in productivity and substitution rates, the economic viability of nurse practitioners must be assessed on a department specific basis, taking into account differences in nurse practitioners’ job descriptions.One specific area this economic efficiency could be assessed in is in the diagnosis of ear infections. A study conducted through the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey showed that 15% of pediatric visits included a diagnosis of middle ear infection (Freid, 1998). If employed properly, nurse practitioners could be used to achieve significant cost savings in this area.This thesis is intended to address the economic efficiency of nurse practitioners as compared to physicians in diagnosing ear infections. First nurse practitioner quality in this specific area will be assessed by comparing nurse practitioner diagnosis error rates to physician error rates based on surveys asking both types of providers to provide diagnoses based on tympanic membrane images collected through previous telemedicine visits. Next the economic practicality of employing nurse practitioners in this field will be assessed in terms of the relative costs of these errors, measured as the cost of unnecessary prescriptions in the case of overdiagnosis and the cost of an unnecessary follow-up visit in the case of underdiagnosis
Thesis (BA) — Boston College, 2012
Submitted to: Boston College. College of Arts and Sciences
Discipline: College Honors Program
Discipline: Economics Honors Program
Discipline: Economics

In this thesis, we consider a discrete time/cost trade-off problem with a single nonrenewable resource. We assume the resource is released at some prespecified time points and at some prespecified quantities. We also assume that the costs due to the activities are incurred at their completions. Our aim is to minimize total project completion time. We formulate the problem as a pure integer programming model. We show that the problem is strongly NP-hard. We find lower bounds by pure linear programming and mixed integer linear programming relaxations of the model. We develop three heuristic procedures using the optimal solutions of mixed integer linear program and pure linear program. The results of our computational study reveal the satisfactory performance of our heuristic procedures.

Over the last two decades there has been a tremendous increase in collaboration among competing firms. A significant number of these collaborations are international. This thesis explores the incentives and welfare consequences of collaboration in the context of international trade. We consider two types of cross-border collaborations. The first is collaboration by sharing a part of firms' value creating activities, such as technology development, product design and distribution. This saves on production costs but reduces product distinctiveness. Firms collaborate if and only if the reduction in product distinctiveness is lower than a threshold level. We find that the threshold increases with an increase in trade costs. That is, an increase in trade costs makes collaboration more likely. Higher trade cost lowers competition, which in turn enables the firms to save on fixed costs while forgoing some product distinctiveness. Furthermore, we demonstrate that contrary to standard intuition, higher trade cost could enhance consumers' welfare by inducing competitors to collaborate. We extend our model to endogenise location choice by the firms where collaboration requires co-location (due to the benefit of local spillovers or joint investment in key infrastructures). Unlike the original model, we find that an increase in trade costs can discourage collaboration. In both circumstances, we find that an increase in trade cost can improve consumer surplus. The second type of collaboration considered in this thesis is licensing. We extend the standard licensing literature to an environment where firms compete in the domestic as well as foreign market. We examine how trade cost affects the licensing decision as well as the optimal payment mechanism. We find that an increase in trade costs reduces the possibility of licensing. Concerning the payment mechanism, we find that (i) either royalty or (ii) a two-part tariff (involving a fixed fee as well as royalty payments) is optimal. An increase in trade costs reduces the likelihood of royalty only being the optimal payment mechanism.

Ao longo das últimas décadas, a crescente pressão competitiva vem ampliando a necessidade de empenho integrado da logística para melhorar, conjuntamente, o atendimento aos consumidores e a lucratividade. O atendimento aos clientes pede o oferecimento de nível de serviço que maximize as utilidades de tempo e de lugar e a busca pela geração de lucros reconhece que a logística, ao oferecer o nível de serviço definido, deve minimizar seu custo total. O custo total logístico não responde às normais técnicas de corte de custos: os custos logísticos movem-se em diferentes direções e a redução de um custo invariavelmente conduz ao aumento de outros custos ou à diminuição do serviço oferecido ao cliente. Como consequência, os profissionais logísticos precisam identificar e explorar os trade-offs de custos logísticos para encontrar e sustentar o balanço entre os custos incorridos e o serviço oferecido. Nesse contexto, o objetivo da presente dissertação foi verificar se os profissionais logísticos: (1) têm conhecimento dos trade-offs de custos logísticos e (2) avaliam os trade-offs de custos logísticos, ao desenharem e implementarem suas soluções. Para atingir esses objetivos, este trabalho caracterizou as atividades logísticas e seus respectivos elementos de custos, explorou o conceito do custo total e sua utilização na determinação das soluções, identificou os trade-offs de custos existentes entre as atividades logísticas, e apresentou e exemplificou modelos de mensuração dos impactos econômico-financeiros dos trade-offs. Tomando esse arcabouço teórico como base, os constructos e o questionário foram definidos. O questionário foi aplicado a profissionais logísticos das maiores empresas brasileiras industriais e comerciais, segundo a Revista Exame Melhores e Maiores do ano base 2010, e 73 respostas foram obtidas. Os resultados indicaram que os profissionais logísticos sabem que os trade-offs de custos logísticos existem, mas não têm clara a percepção que o custo total é determinado por esses trade-offs e que a redução individual dos custos pode aumentá-lo e não diminuí-lo. A pesquisa também evidenciou que a avaliação dos trade-offs é enfatizada em soluções de grande amplitude e que há uma defasagem entre as informações contábeis necessárias e as informações efetivamente recebidas. Foram também expostos fatores associados ao conhecimento e à avaliação dos trade-offs e elaborados mapas perceptuais que articularam os setores econômicos a esses constructos.
In recent decades, competitive pressures have been enhancing the need for an integrated effort of logistics to improve customer satisfaction and company\'s profit. Customer satisfaction demands a service level that maximizes time and place utility and the search for profit acknowledges that logistics, at a given customer service level, should minimize its total cost. Total cost does not respond to usual cost-cutting techniques: logistics costs move in different directions and reductions in one cost invariably increase other costs or decrease the customer service level. Consequently, logistics professionals need to identify and explore logistics cost trade-offs to find and sustain the right balance of cost and service. In this context, the goal of this master\'s thesis was to verify if logistics professionals: (1) know the logistics cost trade-offs and (2) analyze trade-offs when they design and implement a solution. To achieve these objectives, this work characterized logistics activities and their costs, explored total cost concept and its application in solutions design, identified cost trade-offs among logistics activities, and presented and exemplified models to measure economic and financial impacts of trade-offs. Based on this theoretical framework, the constructs and the questionnaire were defined. The questionnaire was applied to logistics professionals of the largest Brazilian commercial and industrial firms in the base year 2010, according to \"Revista Exame Melhores e Maiores\", and 73 answers were obtained. The results showed that logistics professionals know that logistics cost trade-offs exist, but do not have a clear understanding that total cost is determined by these trade-offs and that individual cost-cutting techniques may lead to greater costs. Furthermore, the results have also revealed that tradeoff analysis is emphasized in wide range solutions and that there is a considerable gap between the required accounting information and that one offered. Finally, factors associated with trade-offs knowledge and analysis were shown and perceptual maps articulating economic sectors to these constructs were elaborated.

This thesis explores how different types of trade costs shape trade patterns and the distribution of economic activity across space. In the first chapter, I study how the choice of transport infrastructure after the division of Germany, in 1949, shaped aggregate outcomes and welfare in the following decades. To this end, I develop and calibrate a quantitative trade model with endogenous infrastructure choice. I find that the West German government reshaped the highway network after division increasing real GDP by 0.7% to 2%. In addition, my results show that pre-division highways were a constraint for the government. Removing this constraint would have increased real GDP by 1.85%. In the second chapter, I explore a different type of trade costs: national borders. I use a new dataset of trade across 269 European regions to estimate the “border effect” in Europe. I find that borders in Europe represent a cost equivalent to a 32.5% tariff. This result is robust to different specifications, controls and to a new estimation strategy that identifies the border effect only from border regions.
Esta tesis explora los diferentes tipos de costes que moldean la distribución espacial de la actividad económica. En el primer capítulo, estudio cómo la construcción de carreteras después de la división de Alemania, en 1949, afectó a variables económicas agregadas y al bienestar. Con este fin, desarrollo y calibro un modelo de comercio cuantitativo con elección endógena de infraestructura. Encuentro que el gobierno de Alemania Occidental reformó la red de autopistas después del shock generando un aumento del PIB real de entre un 0,7 % y un 2 %. Sin embargo, mis resultados muestran que las autopistas construidas antes de la división crearon una restricción para el gobierno. La eliminación de esta restricción habría aumentado el PIB real un 1,85 % adicional. En el segundo capítulo, exploro un tipo diferente de costes comerciales: las fronteras nacionales. Utilizo datos de comercio entre 269 regiones europeas para estimar el “efecto de frontera” en Europa. Encuentro que las fronteras en Europa representan un coste equivalente a un arancel del 32,5 %. Este resultado es robusto a diferentes metodologías de estimación y a una nueva estrategia empírica que identifica el efecto usando regiones fronterizas.

The time/cost trade-off models in project management aim to compress the project completion time by accelerating the activity durations at an expense of additional resources. The budget problem in discrete time/cost trade-off scheduling selects the time/cost mode -among the discrete set of specified modes- for each activity so as to minimize the project completion time without exceeding the available budget. There may be alternative modes that solve the budget problem optimally, however each solution may have a different total cost value. In this study we aim to find the minimum cost solution among the optimal solutions of the budget problem. We analyze the structure of the problem together with its linear programming relaxation and derive some mechanisms for reducing the problem size. We solve the reduced problem by linear programming relaxation and branch and bound based approximation and optimization algorithms. We find that our branch and bound algorithm finds optimal solutions for medium-sized problem instances in reasonable times and the approximation algorithms produce high quality solutions. We also discuss the way our algorithms could be used to construct the time/cost trade-off curve.

This thesis comprises a three papers. The chapters stand on their own. Each paper-chapter analyses a specific issue and contains introduction, theoretical framework, methods of analyses, results and findings. Each of the chapters offers new empirical, methodological and modelling contributions with new empirical evidence and findings, with new extensions and specifications for the gravity based and CGE based analytical tools. The thesis reflects my analysis of regional and international trade of Central Asia by analyzing the past economic ties of the CA with former Big Brother , Russia; the present heterogeneity of socio-economic environment of CA countries; and the future development of CA trade relations with the formation of the Eurasian (Re)Union. The Introductory Chapter binds together the other chapters by discussing the general background of the Central Asian institutional formation, transition and trade relations; the research motivations and methodology employed in this thesis. Afterwards come three substantive chapters. In the first chapter, the analysis of enhancing economic relations between Russia and CA in the post-Soviet period contradicts the post-colonial trade erosion theory. In the second chapter, how the open or isolationist policies followed by Central Asian countries affect the performance of local firms and MNEs, and linked to the economic performances of the countries, is investigated. In the third chapter, the impact of deeper Eurasian regional economic integration is assessed quantitatively in the context of asymmetry between the union members and the EU deeper integration project. The final chapter discusses the limitations and possible directions for future research.

The purpose of this research is to analyze the framework the Department of Defense (DoD) is undertaking with renewable energy and energy efficiency initiatives across military installations to determine the potential savings the United States Marine Corps (USMC) and DoD could realize by managing investments in renewable energy in all installations as a portfolio of opportunities, maximizing benefits and sustainability. In addition, this study evaluates renewable energy resource technologies that have long-term the best economic stability and least challenges for future growth on military installations. It also describes how the challenges of human behavior, budget cuts, financing approaches and regulations may play a big part in harnessing the optimal benefit from renewable energy resources. This study analyzes how comprehensive knowledge management in combination with renewable energy efforts across installations can capitalize DoD cost savings for long-term stability. This research recommends DoD take a comprehensive strategy approach through risk management analysis, information sharing, and better business practices.

Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2009.
Includes bibliographical references (leaf 66).
This thesis discusses the tradeoff between transportation cost and the level of service in cold chain transportation. Its purpose is to find the relationship between transportation cost and the level of service in cold chain transportation. Regression models are built to quantify the additional cost of superior quality cold chain for both Chiquita and its carriers, and analyze the relationship between such cost and customer service level. In order to guarantee the freshness of salads and fruits, cold chain transportation has to meet strict quality standards and additional costs occur due to efforts required to maintain and monitor the transportation performance. The thesis takes quantitative approach to demonstrate the relationships among the quality standards required, the cost associated, and the customer service level reached. The temperature quality standards are mainly measured by monitoring data from RFID monitor Sensitech. The cost data are collected from Chiquita's historical carrier rates. The customer service level is measured in two dimensions, on time drop-off, and on time pick-up. The thesis also takes qualitative approach by a survey on carriers' additional cost of offering superior cold chain transportation among Chiquita's carriers. No correlation is found between transportation cost and the level of service in cold chain transportation. Therefore carriers with best cold chain management don't necessarily charge the highest.
by Saiqi Liu.
M.Eng.in Logistics

The main objective of this study was to estimate the costs associated with different storage levels of maize for the National Cereals and Produce Board (the NCPB), the grain marketing agency of the Kenyan government.
Four storage level scenarios were considered. The first involved a zero-supply security scenario, where the model was required to simply satisfy the demand in each period. The second, third and fourth respectively, involved two, three and four months supply security scenarios, where the model was required to purchase grain equivalent to the demand for those periods. Scenario two, providing two months supply security was not discussed because it posted results similar to scenario one. The hypothesis that a stocks management model can be developed to be used by the NCPB in order to determine the optimal quantities of maize that it handles every year, while minimizing costs, was partly supported under scenarios one and three. However, despite the reduction in costs under scenario one, the lack of inventory and foreign trade was seen to increase the risks and uncertainties associated with variations in production, especially under cases of short supply. Similarly, the lack of foreign trade under scenario three was postulated to increase risks and uncertainties in periods of low production. Under scenario four, the results involved foreign trade, and inventory was positive for most years. However, these results were suboptimal and thus unreliable for policy decisions. Nevertheless, results under this scenario were very similar to the actual performance of NCPB for the period 1980 to 1990.
The results of this study show that external trade may not be the solution to a strategy of cost minimization. It was concluded, therefore, that the present strategy of self-sufficiency may be the better alternative. (Abstract shortened by UMI.)

Doctor of Philosophy
Department of Economics
Yang-Ming Chang
This dissertation comprises three chapters in international trade and the economics of conflict. These chapters are put together according to two dimensions. From the international relations dimension, Chapter 1 analyzes free trade, which is the most “liberal” form of international relation; Chapter 2 analyzes different types of trade agreements, which is the most common and “moderate” form of international relation; and Chapter 3 analyzes conflict, which is the most violent and “extreme” form of international relation. From the proximity dimension, free trade usually occurs between countries that are far from each other, trade agreements usually signed by countries with in a region, and conflict usually happens between two very close countries. Chapter 1 develops a novel model of international trade in which transportation costs are driven by trade imbalance of an individual country. This task is accomplished by assuming a representative transportation firm in each country that competes with its counterparts from other countries for international operation. The model of trade imbalance driven costs complements results from traditional international trade model in that it sheds light on how trade costs are affected by country size. With multiple countries and a continuum of production firms in each country under monopolistic competition, we derive an index of transportation costs to capture bilateral trade barriers for country pairs. This index is time-variant, which makes it suitable for panel data studies. Based on the index, simulation and simplified three-country free trade model show that countries with a relatively larger size incur a trade deficit while smaller size implies a trade surplus under free trade. A gravity equation is derived and estimated using Poisson Pseudo Maximum Likelihood. Estimation results support the fitness and robustness of the theoretical model of trade using the constructed transportation cost index. Further, statistical test shows that this transportation cost index is a better approximation of bilateral trade cost than distance. A growing number of recent regional trade agreements (RTAs) have introduced provisions concerning cross-border investments. Likewise, a substantial number of RTAs have been preceded by agreements regarding cross-border investments. In Chapter 2, we develop a partial equilibrium three-country model to examine the relationship between RTAs and FDI while also allowing for double taxation. Our analysis shows that the formation of an RTA between two regional countries with wage asymmetry is welfare-improving for the low-wage country and the region, but can be welfare-deteriorating for the high-wage country. We extend our analysis to examine the role of repatriation taxes in the determination of firm location when an RTA is and is not established. Our final result suggests that the signing of an RTA would not induce the relocation of a plant from the high-wage country to the low-wage country unless a reduction of the repatriation tax rate also occurs. In Chapter 3, we attempt to resolve the “inefficiency puzzle of war” by developing a general equilibrium model of bargaining and fighting with endogenous destruction. In the analysis, we consider the scenario that two contending parties engage in bargaining to avoid fighting when there are direct costs (e.g., arms buildups) and indirect costs (e.g., destruction to consumable resources) of conflict. Taking into account different modes of “destruction technology” (in terms of weapons’ destructiveness) without imposing specific functional form restrictions on conflict technology and production technology, we characterize their interactions in determining the Nash equilibrium choice between fighting and bargaining. We find that bargaining is costly as the contending parties always allocate more resources to arming for guarding their settlement through bargaining (but under the shadow of conflict) than in the event of fighting. Contrary to conventional thinking that bargaining is Pareto superior over fighting, we show conditions under which fighting dominates bargaining as the Nash equilibrium choice. The positive analysis may help explain the general causes of fighting, strikes, international conflict, and wars without incomplete information or misperceptions.

This thesis is concerned with the analysis of shipping cost in theory and in the practice of Saudi shipping companies. Previous studies on cost structures and cost functions have been surveyed. Factors which affect each cost element have been derived from the surveyed studies to be used in establishing the cost functions of Saudi vessels. The empirical part of the thesis covers many related topics. First, costing systems and cost reports in Saudi shipping companies have been evaluated. Second, cross sectional cost and operation data of vessel samples in Saudi Arabia have been analysed. The results of this analysis are cost structures and cost functions. Several statistical techniques have been used for the analyses of cost data in the empirical part of the thesis. On the basis of this investigation, the researcher has arrived at several propositions. The most important contribution of the thesis is that it presents to the management of Saudi shipping companies relevant information to establish policies for cost reduction.

The aim of this thesis is to examine a cost- benefit analysis of the petrochemical industry comparing the costs of production, such as capital cost, labour cost, etc. in Saudi Arabia, and show the degree of its competitiveness in the international market. Also it discusses and evaluates the industrial development process in Saudi Arabia. The labour shortage and the marketing problems of the petrochemical products will be examined and solutions to these problems will be given. This research started by dealing with the theoretical background of the development planning. Various sources of energy literature have been reviewed, describing the role that hydrocarbon resource exploitation played in the Saudi development plans. Its objectives are to identify and understand the development problems, its strategies, objectives and plans of the Saudi government by paying attention to the role of the oil and gas resources and the country opportunities for diversification of the economy and decreasing dependence on crude oil and to use their limited resources more efficiently. Various procedural approaches were considered for evaluating development projects in order to increase the effectiveness of the development programs in Saudi Arabia. These include: improving the people's welfare, increasing national income, expanding the country's absorptive capacity and shifting to a renewable resource base. The petrochemical industry is the most feasible industry to be established in Saudi Arabia at this time. It would provide the country with the best alternative for steady economic growth with decreasing emphasis on the export of oil. The thesis will try to prove that the development of the petrochemical industry in Saudi Arabia is an adequate economic project, only if the major constraints such as labour shortage and marketing and profitability on the international market for petrochemical products can be overcome or at least minimised.

The U.S. Navy has been confronted with budget cuts and constraints during recent years. This reduction in budget compels the U.S. Navy to limit the number of manpower and personnel to control costs. Reducing the total ownership cost (TOC) has become a major topic of interest for the Navy as plans are made for current and future fleets. According to the U.S. Government Accountability Office (GAO, 2003), manpower is the most influential component of determining the life cycle cost of a ship. The vast majority of the TOC is comprised of operating and support (O&S) costs which account for approximately 65 percent of the TOC. Manpower and personnel costs account for approximately 50 percent of O&S costs. This research focused on tradeoff analysis and cost estimation between manpower and new technology implementation. Utilizing concepts from System Dynamics Modeling (SDM), System Dynamics Causal Loop diagrams (CLD) were built to identify major factors when implementing new technology, and then stocks and flows diagrams were developed to estimate manpower cost associated with new technology implementation. The SDM base model reflected an 18 months period for technology implementation, and then compared different technology implementation for different scenarios. This model had been tested by the public data from Department of the Navy (DoN) Budget estimates. The objective of this research was to develop a SDM to estimate manpower cost and technology tradeoff analysis associated with different technology implementations. This research will assist Navy decision makers and program managers when objectively considering the impacts of technology selection on manpower and associated TOC, and will provide managers with a better understanding of hidden costs associated with new technology adoption. Recommendations were made for future study in manpower cost estimation of ship systems. In future studies, one particular type of data should be located to test the model for a specific manpower configuration.
Ph.D.
Doctorate
Industrial Engineering and Management Systems
Engineering and Computer Science
Modeling and Simulation; Engineering

As a promising field, the development of smart grid has drawn more and more attention from many countries. A smart meter plays a significant role in a smart grid. It replaces the traditional electricity meter with the ability to frequently transmit instantaneous energy consumptions of the consumer to theenergy provider of the smart grid. From the view of electricity suppliers, it isbeneficial for planning, controlling and billing. However, from consumers’ perspective, the high-resolution energy record may lead to privacy problem, which means the consumers’ behaviour can be revealed by analysing the smart meter readings. In this thesis project, we will focus on the privacy leakage problem of the smart meter. We study the problem of optimal privacy-cost trade-off in a smart grid equipped with an energy provider, an alternative energy source, a smart meter,and an energy control unit. The privacy leakage is modelled as unauthorized detections of the consumer’s behaviours based on the smart meter readings of energy supplies from the energy provider. The control strategy is designed to manage the energy inflows to satisfy the instantaneous energy demands of the consumer and also to optimally trade off the privacy risk and energy cost. To evaluate the privacy risk, we use a Bayesian detection-operational privacy metric. Different scenarios are considered for which we show that their optimization problems can be reduced to linear programmings. Therefore, based on this observation, we propose optimal control strategy design algorithms to solve the optimization problems efficiently.
Inom ett potentiellt område, har utvecklingen av smarta elnät dragit mer och mer uppmärksamhet från många länder. En smart elmätare spelar en signifikant roll i ett smart elnät. Den ersätter den traditionella elmätaren med förmågan att ofta överföra den momentana energiförbrukning som konsumenten mottar av energileverantören av smarta elnät. Från elleverantörens sida, är det fördelaktigt för planering, styrning och fakturering. Men från konsumenternas perspektiv kan den högupplösta energiförbrukningen leda till integritetsproblem, vilket innebär att konsumenternas beteende kan avslöjas genom att analysera de smarta mätaravläsningarna. I detta projekt kommer vi fokusera på integritetsproblemen som dessa mätare ger upphov till. Vi studerar problemet med att balansera integritetsproblemeti ett smart elnät bestående av en energileverantör, en alternativ energikälla, ensmart mätare, och en energistyrenhet. Den personliga integriteten äventyras dåen obehörig kan få tillgång till konsumentens beteende baserat på de smartamätvärdena av energiförbrukningen från energileverantören. Kontrollstrateginär utformad för att hantera energiinflödet för att tillfredsställa de momentanaenergibehov konsumenten har, och även för att optimalt avväga privatlivs riskoch energikostnader. För att utvärdera den personliga integriteten risk, an-vänder vi en Bayesiansk upptäckt dvs. operativ integritets uträkning. Olikascenarier beaktas och deras optimeringsproblem kan reduceras till linjära pro-grammeringar. Baserat på observationen är motsvarande kontrollstrategi meddesignade algoritmer att föredra.

In this thesis, meta-heuristic algorithms are developed to obtain optimum or near optimum solutions for the time-cost-resource trade-off and resource leveling problems in project scheduling. Time cost trade-off, resource leveling, single-mode resource constrained project scheduling, multi-mode resource constrained project scheduling and resource constrained time cost trade-off problems are analyzed. Genetic algorithm simulated annealing, quantum simulated annealing, memetic algorithm, variable neighborhood search, particle swarm optimization, ant colony optimization and electromagnetic scatter search meta-heuristic algorithms are implemented for time cost trade-off problems with unlimited resources. In this thesis, three new meta-heuristic algorithms are developed by embedding meta-heuristic algorithms in each other. Hybrid genetic algorithm with simulated annealing presents the best results for time cost trade-off. Resource leveling problem is analyzed by five genetic algorithm based meta-heuristic algorithms. Apart from simple genetic algorithm, four meta-heuristic algorithms obtained same schedules obtained in the literature. In addition to this, in one of the test problems the solution is improved by the four meta-heuristic algorithms. For the resource constrained scheduling problems
genetic algorithm, genetic algorithm with simulated annealing, hybrid genetic algorithm with simulated annealing and particle swarm optimization meta-heuristic algorithms are implemented. The algorithms are tested by using the project sets of Kolisch and Sprecher (1996). Genetic algorithm with simulated annealing and hybrid genetic algorithm simulated annealing algorithm obtained very successful results when compared with the previous state of the art algorithms. 120-activity multi-mode problem set is produced by using the single mode problem set of Kolisch and Sprecher (1996) for the analysis of resource constrained time cost trade-off problem. Genetic algorithm with simulated annealing presented the least total project cost.

This work proposes a method for estimating the development cost of a software system with modular structure taking into account the target level of reliability for that system. The required reliability of each individual module is set in order to meet the overall required reliability of the system. Consequently the individual cost estimates for each module and the overall cost of the software system are linked to the overall required reliability. Cost estimation is carried out during the early design phase, that is, well in advance of any detailed development. Where a satisfactory compromise between cost and reliability is feasible, this will enable a project manager to plan the allocation of resources to the implementation and testing phases so that the estimated total system cost does not exceed the project budget and the estimated system reliability matches the required target. The line of argument developed here is that the operational reliability of a software module can be linked to the effort spent during the testing phase. That is, a higher level of desired reliability will require more testing effort and will therefore cost more. A method is developed which enable us to estimate the cost of development based on an estimate of the number of faults to be found and fixed, in order to achieve the required reliability, using data obtained from the requirements specification and historical data. Using Markov analysis a method is proposed for allocating an appropriate reliability requirement to each module of a modular software system. A formula to calculate an estimate of the overall system reliability is established. Using this formula, a procedure to allocate the reliability requirement for each module is derived using a minimization process, which takes into account the stipulated overall required level of reliability. This procedure allow us to construct some scenarios for cost and the overall required reliability. The foremost application of the outcome of this work is to establish a basis for a trade-off model between cost and reliability during the design phase of the development of a modular software system. The proposed model is easy to understand and suitable for use by a project manager.

The energy consumption of communication networks is continuously growing. Many energy saving approaches have been proposed at the device, system, and network level. The most promising way to address this problem is to utilize photonic technologies as much as possible thanks to their low energy consumption per bit performance. Moreover, several approaches have been proposed to further reduce the energy consumption in optical networks. One popular technique exploits low power modes (e.g., sleep or doze mode) for devices that are not used. However, sleep mode based approaches may affect the way optical connections (i.e., lightpaths) are routed, or alter the characteristics of some devices. This in turn may have a detrimental impact on crucial network/device performance parameters. In other words a green approach may introduce additional delay, change the level of resource utilization in the network, or even impact the lifetime of a device, resulting in increased network operational cost. This thesis provides a study that carefully assesses, in both access and core networks, the trade-off between the benefits of sleep-based energy-efficient schemes and their possible side-effects. In fiber access networks putting a device into sleep mode and waking it up can introduce a significant energy overhead. Already proposed energy-efficient approaches reduce this overhead by aggregating as much as possible the traffic before a transmission. However, aggregating data may cause an additional delay that in some cases might not be acceptable. This thesis investigates the trade-off between energy saving and additional packet delay in the case of a LTE backhaul network based on wavelength division multiplexing passive optical network (WDM-PON). The thesis proposes a novel energy-efficient approach based on the dozing concept able to precisely control when a transmitter needs to wake up in order to maximize the time spent in sleep mode, while assuring that packet transmissions are completed before a given deadline. The proposed scheme is also able to exploit possibly diverse traffic delay requirements to further improve energy saving performance. In optical core networks, one way to decrease the energy consumption is to minimize the number of used active devices by aggregating the lightpaths on the lowest possible number of active fiber links. Routing strategies based on this intuition are beneficial in terms of energy saving, but on the other hand may impact the network performance (e.g., blocking probability) by affecting length of the lightpaths and link occupancy distribution. This trade-off is evaluated in the thesis with the help of a specially designed routing and wavelength assignment (RWA) strategy referred to as weighted power aware lightpath routing (WPA-LR). The WPA-LR strategy permits the fine tuning between the minimization of two objectives: energy consumption and network resource (i.e., wavelength) utilization. Evaluation results confirm that energy efficiency and network performance are conflicting objectives. However, the proposed WPA-LR strategy offers energy minimization with acceptable impact on the network performance. The thesis also investigates the impact that sleep-based energy-efficient strategies have on the lifetime of a number of optical network devices, in both access and core networks. In fact, utilizing a sleep mode functionality may change the operational conditions of the device which can impact the device lifetime. This is a crucial aspect to consider because it may directly affect the network operational cost related to fault management. The thesis provides a methodology to assess under which conditions and for which devices an energy-efficient scheme may lead to overall cost benefit vs. a (possible) increase of reparation cost. It was found that in access networks and with business customers a small lifetime variation in optical line terminals (OLTs) or in optical network units (ONUs) can lead to significant cost increase that cannot be covered by the profits coming from the energy saving. In core networks erbium doped fiber amplifiers (EDFAs) are the most vulnerable devices in terms of impact on their lifetime. For this reason it was found that the usage of green routing algorithms based on putting EDFAs into sleep mode may not always be economically beneficial. In conclusion this thesis provides a different perspective on sleep mode based energy-efficient algorithms where the potential benefit in terms of energy saving is weighted against the impact of a possible degradation of the network performance and devices lifetime. On the other hand these performance degradations can be controlled and limited by the proposed algorithms.
Energikonsumtionen av kommunikationsnätverk, växer kontinuerligt. Många energibesparande åtgärder har föreslagits, såväl på komponentnivå, systemnivå och nätverksnivå. Det mest lovande sättet att hantera energibehov i kommunikationsnätverk är att utnyttja optisk teknologi så mycket som möjligt då denna har potential att ge låg energiförbrukning per bit. Det finns också ett antal föreslagna metoder för att ytterligare reducera energibehovet i optiska nätverk. En av de mest använda teknikerna bygger på att låta enheter som ej används gå ner på låg effekt (”sovläge”). Om detta används i allt för hög utsträckning kan det dock påverka hur optiska förbindelser (sk lightpaths) sätts upp eller ge förändrade egenskaper hos de aktuella komponenterna. Detta kan i sin tur ha en skadlig inverkan på de centrala nätverks- och komponentegenskaper vilket påverkar prestandan. Med andra ord kan en sådan ”grön” ansats baserad på sovläge leda till ökad fördröjning, förändring av resursutnyttjandet i nätet och till och med påverka risken för att det uppstår fel i komponenterna vilket ökar driftskostnaden för nätet. Denna avhandling fokuserar på dessa aspekter och visar upp resultat som belyser avvägningen mellan sovlägesbaserade energieffektiva strategier och deras eventuella bieffekter. Att slå av och väcka upp komponenter i optiska access-nätverk kan vara förknippat med en signifikant extra energikostnad. Tidigare föreslagna energieffektiva strategier försöker reducera denna ökade energikostnad genom att samla så mycket trafik som möjligt innan överföringen sker. Dock kan detta leda till ökad fördröjning som i vissa lägen inte är acceptabel. I avhandlingen undersöker vi avvägningen mellan energibesparingar och ökad paketfördröjning i fallet med LTE distributionsnät baserade på våglängsmultiplexerade passiva optiska nätverk (WDM-PON). Vi föreslår en ny energieffektiv ansats baserad på att enheter försätts i ”slummer-läge”. Detta gör det möjligt att med god precision bestämma när en sändare behöver väckas upp i syfte att maximera tiden i sovläget och att försäkra sig om att paketen kommer fram inom avsedd tid. Strategin är även kapabel att utnyttja differentierad fördröjning för att ytterligare förbättra energibesparingen. Ett sätt att minska energikonsumtionen i optiska distributionsnät är att minimera antalet aktiva enheter genom att exempelvis samla optiska förbindelser till ett minimalt antal aktiva fiberlänkar. Routingstrategier som utgår från denna princip är fördelaktiga ur energisynpunkt men kan å andra sidan skada nätverksprestanda (exempelvis blockeringssannolikhet) genom påverkan på förbindelselängder och annorlunda belastning av länkarna. Denna avvägning utvärderas i avhandlingen med hjälp av en specifikt utformad strategi för routing och våglängstilldelning (RWA) som vi benämner ”viktad effektmedveten optisk förbindelserouting” (WPA-LR). Denna strategi möjliggör noggrann avvägning mellan minimeringen av två kriterier: å ena sidan energikonsumtion, å andra sidan utnyttjandet av nätverksresurser (speciellt väglängdsutnyttjandet). Vår utvärdering bekräftar att energieffektivitet och nätverksprestanda står i motsatsförhållande till varandra. Dock erbjuder WPA-LR strategin minimering av energin med en acceptabel påverkan på nätverksprestanda. Slutligen undersöks i avhandlingen den påverkan som sovlägesbaserade energieffektiva strategier har på livslängden för optiska nätverkskomponenter, både i access- och i distributionsnät. Användning av sovlägesfunktion kan påverka arbetsförhållandena för en komponent, något som i sin tur kan påverka livslängden. Detta är en kritisk aspekt att ta i beaktande då det direkt kan påverka driftskostnaden kopplad till nätunderhållet. En metod ges för att utvärdera under vilka förhållanden och för vilka enheter en energieffektiv strategi kan leda till en total kostnadsfördel jämfört med en (möjlig) ökning av reparationskostnaderna. Ett resultat är att, i accessnät och för företagsanvändare, så kan även en liten variation i feluppkomst i optiska linjeterminaler (OLTs) eller optiska nätverksenheter (ONUs) leda till signifikanta kostnadsförluster vilka inte kan kompenseras genom de vinster som kan åstadkommas med energibesparingar. I distributionsnät är erbium-dopade fiberförstärkare (EDFAs) de mest utsatta enheterna vad gäller inverkan på livslängd. Genom att studera routingstrategier (ex.vis WPA-LR) har vi funnit att användningen av ”gröna” routingalgoritmer baserade på att lägga EDFAs i sovläge inte alltid är ekonomiskt fördelaktigt. Denna avhandling ger ett perspektiv på sovlägesbaserade energieffektiviseringsalgoritmer där de potentiella fördelarna vad gäller minskade driftskostnader ställs mot möjliga försämringar av nätverksprestanda och komponenters livslängd. Å andra sidan kan dessa försämringar hållas under kontroll och begränsas av den föreslagna algoritmen.
La consommation d'énergie des réseaux de communication ne cesse de croître. Ce problème fait l’objet de nombreuses approches orientées vers les économies d'énergie (écoénergétiques) au niveau des appareils (équipements) des systèmes et des réseaux. La façon la plus prometteuse de limiter l’augmentation de consommation évoquée est d'utiliser autant que possible des technologies photoniques, vu leur faible consommation d'énergie par bit. Plusieurs autres approches ont été proposées pour réduire davantage encore la consommation d'énergie dans des réseaux optiques. Une technique populaire exploite les modes de faible puissance (par exemple le mode veille) pour les appareils qui ne sont pas utilisés. Cependant, les approches basées sur le mode de veille peuvent affecter la manière dont les liaisons optiques (circuits optiques) sont acheminées, ou modifier les caractéristiques de certains appareils. Cela peut avoir un impact négatif sur les paramètres de performance des réseaux/équipements cruciaux. En d'autres termes, une approche écoénergétique peut introduire un retard supplémentaire, changer le niveau d'utilisation des ressources dans le réseau, ou même avoir un impact sur le taux d'échec d'un équipement, entraînant une augmentation des coûts d'exploitation du réseau. Cette thèse évalue attentivement, à la fois dans le réseau d'accès mais aussi dans le cœur du réseau, le compromis entre les avantages des régimes économes en énergie utilisant le mode veille et leurs effets secondaires possibles. Dans les réseaux d'accès optiques, mettre un équipement en mode veille et le réactiver peut introduire une surcharge d'énergie significative. Les approches d'économie d'énergie déjà proposées réduisent cette surcharge en regroupant autant que possible le trafic avant sa transmission. Toutefois, les données d'agrégation peuvent provoquer un retard supplémentaire qui peut ne pas être acceptable dans certains cas. Cette thèse étudie le compromis entre les économies d'énergie et un retard supplémentaire des paquets dans le cas d'un réseau backhaul LTE basé sur réseau optique passif à multiplexage en longueur d'onde (WDM-PON). La thèse propose une nouvelle approche éco énergétique. Elle développe un concept au travers duquel il est possible de contrôler avec précision quand un émetteur doit se réactiver, afin de maximiser le temps passé en mode veille tout en veillant à ce que les transmissions de paquets soient terminées en temps voulu. Le schéma proposé est également capable d’exploiter les (éventuelles) exigences diverses de retard de trafic pour améliorer encore les économies d'énergie. Dans le cœur des réseaux optiques, on peut diminuer la consommation d'énergie en minimisant le nombre d’équipements actifs utilisés pour l’acheminement des circuits optiques et le nombre de liens actifs à fibres optiques. Les stratégies de routage basées sur ce principe sont bénéfiques en termes d'économie d'énergie, mais peuvent affecter les performances du réseau (par exemple, la probabilité de blocage) en affectant la longueur des circuits optiques et la distribution d’occupation des liens. Ce compromis est évalué dans la thèse avec l'aide d’une stratégie de routage et affectation de longueur d'onde (RWA) appelée routage des circuits optiques conscient de la puissance (WPA-LR). La stratégie WPA-LR permet le réglage fin entre deux objectifs: minimiser la consommation d'énergie et minimiser l’utilisation des ressources réseau (i.e. longueur d'onde). Les résultats de l'évaluation confirment que l'efficacité énergétique et les performances du réseau ont des objectifs contradictoires. Cependant, la stratégie WPA-LR proposée permet la minimisation de l'énergie avec un impact acceptable sur les performances du réseau. La thèse étudie également l'impact que les stratégies d’économie d’énergie basées sur le mode veille ont sur la durée de vie d'un certain nombre d’équipements de réseau optique, dans les deux réseaux d'accès et de base. L'utilisation du mode veille peut en effet modifier les conditions de fonctionnement de l’équipement, ce qui peut influer sur la durée de vie de l'appareil. Ceci est un aspect crucial à considérer, car il peut affecter directement le coût opérationnel du réseau lié à la gestion des pannes. La thèse propose une méthodologie pour évaluer dans quelles conditions et pour quels dispositifs un système économe en énergie peut conduire à des avantages de coûts globaux par rapport à une (possible) augmentation des coûts de maintenance. Dans les réseaux d'accès et auprès de clients commerciaux, il a été constaté qu’une petite variation de taux d'échec dans les terminaux de ligne optique (OLT) ou dans les unités de terminaison de réseau optique (ONUs) peut conduire à des pertes financières importantes qui ne peuvent être compensées par les bénéfices provenant des économies d'énergie. Dans les cœurs de réseaux les amplificateurs à fibre dopée en erbium (EDFA) sont les équipements les plus vulnérables en termes d'impact sur leur durée de vie. Pour cette raison, l'utilisation d'algorithmes de routage écoénergétiques basé sur la mise en mode veille des EDFA peut par conséquent n’être pas toujours économiquement avantageuse. En conclusion, cette thèse fournit une perspective différente sur des algorithmes économes en énergie basés sur l’utilisation du mode veille. Leur bénéfice potentiel en termes d'économie d'énergie est comparé à l'impact d'une éventuelle dégradation d’une part de la performance du réseau et d’autre part de la durée de vie des équipements. Ces dégradations de performances peuvent être contrôlées et limitées par les algorithmes proposés.
Zużycie energii elektrycznej w sieciach komunikacyjnych stale rośnie. Do tej pory zostało zaproponowanych wiele metod oszczędzania energii na poziomie urządzeń, systemów i sieci. Najbardziej obiecującym podejściem do tego problemu jest wykorzystanie technologii optycznych, z uwagi na ich niskie zużycie energii „per bit”. Ponadto wiele różnych metod przeznaczonych dla sieci optycznych zostało przedstawionych w literaturze. Jedna z popularnych technik wykorzystuje tryb niskiego poboru energii (uśpienia) w urządzeniach, które nie są używane. Jednakże techniki wykorzystujące tryb uśpienia mogą mieć wpływ na kierowanie optycznych połączeń sieciowych (lightpaths) lub zmieniać właściwości urządzeń. Natomiast to może mieć negatywny wpływ na kluczowe parametry wydajności sieci czy urządzeń sieciowych. Innymi słowy algorytmy oszczędzające energię mogą wprowadzić dodatkowe opóźnienia, zmienić wykorzystanie zasobów sieciowych, a nawet wpływać na awaryjność urządzeń zwiekszając tym samym koszt eksploatacji sieci. Praca ta przedstawia i analizuje kompromis pomiędzy korzyściami płynącymi z energooszczędnych algorytmów opartych na trybie uśpienia, a ich ewentualnymi skutkami ubocznymi, zarówno w sieciach dostępowych, jak i szkieletowych. W przypadku optycznych sieci dostępowych proces wprowadzenia urządzenia w tryb uśpienia i jego wybudzenia może spowodować znaczący narzut energetyczny. Proponowane sposoby zmniejszenia tego narzutu agregują ruch sieciowy przed jego transmisją, Jednakże taka agregacja powoduje dodatkowe opóźnienia transmisji, które w niektórych przypadkach mogą być niedopuszczalne. Praca ta analizuje kompromis pomiędzy oszczędzaniem energii, a dodatkowymi opóźnieniami transmisji w przypadku sieci LTE-backhaul, bazowanej na technologii pasywnych sieci optycznych, opartych na multipleksowaniu z podziałem długości fali WDM-PON (Wavelength Division Multiplexing Passive Optical Network). Niniejsza praca proponuje nowatorską metodę oszczędzania energii, opartą na koncepcji drzemki (dozing), która precyzyjnie kontroluje czas wybudzania nadajnika, tak aby zmaksymalizować czas spędzony w trybie drzemki, przy zapewnieniu, że transmisja danych zostanie zakończona przed upływem wymaganego czasu. Proponowana metoda wykorzystuje również zróżnicowane wymagania maksymalnych opóźnień transmitowanych danych do dalszej poprawy wydajności energetycznej. Jednym ze sposobów zmniejszania zużycia energii w światłowodowych sieciach szkieletowych jest zredukowanie liczby aktywnych urządzeń, poprzez umiejętne kierowanie optycznych połączeń sieciowych przy użyciu już aktywnych łączy światłowodowych. Kierowanie ruchu sieciowego oparte na tym pomyśle jest korzystne z punktu widzenia oszczędzania energii, choć z drugiej strony może mieć wpływ na parametry wydajnościowe sieci (np. zwiększenie prawdopodobieństwa blokady połączeń) poprzez oddziaływanie na długość połączeń, czy zajętość łączy. Przytoczony problem jest analizowany w tej pracy za pomocą specjalnie zaprojektowanego algorytmu routingu i przypisania długości fali RWA (Routing and Wavelength Assignement), nazwanego WPA-LR (Weighted Power Aware Lightpath Routing). Algorytm WPA-LR pozwala na precyzyjną regulację pomiędzy redukcją zużycia energii i optymalizacją wykorzystania zasobów sieciowych. Wyniki wykonanej analizy problemu potwierdzają, że efektywność energetyczna i wydajność sieci to cele ze sobą sprzeczne. Jednakże proponowana strategia (WPA-LR) umożliwia kontrolę i osiągnięcie kompromisu pomiędzy zmniejszeniem zużycia energii, a pogorszeniem wydajności sieci. Praca ta bada również wpływ energooszczędnych strategii, opartych o tryb uśpienia, na trwałość optycznych urządzeń sieciowych, zarówno w sieciach dostępowych, jak i szkieletowych. Używanie trybu uśpienia może zmienić warunki pracy urządzenia, które z kolei mogą mieć wpływ na jego trwałość. Natomiast zmniejszenie trwałości urządzenia może bezpośrednio oddziaływać na koszt eksploatacji sieci związany z zarządzaniem awariami. Niniejsza praca proponuje metodologię oceny, na jakich warunkach i w przypadku których urządzeń, używanie algorytmów oszczędzania energii może prowadzić do ogólnych korzyści finansowych lub strat związanych ze wzrostem kosztu eksploatacji sieci. W pracy stwierdzono, że w sieciach dostępowych, w szczególności obsługujących klientów biznesowych, mały wpływ na awaryjność optycznych terminali ONU (Optical Network Unit) lub optycznych urządzeń dystrybucyjnych OLT (Optical Line Terminal) może prowadzić do znacznego zwiększenia kosztów, które mogą przekroczyć zyski związane z oszczędzaniem energii. W sieciach szkieletowych wzmacniacze światłowodowe EDFA (Erbium Doped Fiber Amplifier) są najbardziej wrażliwymi urządzeniami pod względem wpływu na ich awaryjność. W pracy dowiedziono, że użycie energooszczędnych algorytmów kierowania połączeń światłowodowych, opartych na wprowadzaniu EDFA w tryb uśpienia, nie zawsze jest korzystne ekonomicznie. Niniejsza praca przedstawia nowatorskie spojrzenie na energooszczędne algorytmy oparte na wprowadzaniu urządzeń w tryb uśpienia, gdzie potencjalne korzyści w zakresie oszczędzania energii są porównane ze stratami związanymi z degradacją wydajności sieci lub żywotności urządzeń sieciowych.

QC 20160509

Bakgrund: Företag söker ständigt nya sätt att designa effektivare flödeskedjor och för att säkerställa lönsamhet eftersträvas en minskning av kostnader inom produktion, transport och lager. Då lagerrelaterade kostnader står för en stor del av företags totala logistikkostnader har det kommit att stå i fokus för kostnadsminskande aktiviteter. Att minska kostnaderna relaterade till lager och samtidigt erhålla en önskad servicegrad benämns lagerstyrning. Ett sätt att uppnå bättre lagerstyrning är att lokalisera slöseri som kan finnas inom dagens styrning. Detta kan göras genom att upprätta en processkartläggning för att därigenom lokalisera och minimera eller eliminera det slöseri som identifieras genom olika förbättringsåtgärder. Syfte: Syftet med denna avhandling är att beskriva Gotlandsäggs nuvarande lagerstyrning av äggförpackningar och vilka kostnader det leder till för företaget. Därefter kommer eventuella slöserier i den nuvarande lagerstyrningen av äggförpackningar att identifieras för att sedan lägga fram förslag för hur lagerstyrningen kan förbättras med målet att minska kostnaderna för företaget samtidigt som önskad servicenivå uppnås. Metod: Studien är en kvalitativ fallstudie på företaget Gotlandsägg ABs förpackningsanläggning i Ruda. Denna har antagit en deduktiv forskningsansats med ett positivistiskt synsätt. Datainsamling har gjorts av både primärdata i form av strukturerade, semistrukturerade och ostrukturerade intervjuer med personal på Gotlandsägg samt sekundärdata som samlats in från Gotlandsäggs system, Linnéuniversitetets databas och tillgänglig litteratur. Slutsats: Studien har beskrivit Gotlandsäggs nuvarande påfyllningsprocess av äggförpackningar genom att upprätta en processkartläggning och fastställt den definierbara årliga kostnaden för lagerstyrningen. Den nuvarande styrningen innebär att förpackningar lagerhålls länge och därmed binder kapital vilket ökar lagerföringskostnaderna. Genom kartläggningen identifierades slöseri i form av en aktivitet som inte var värdeskapande, nyttjandet av ett manuellt lagersaldo, samt slöseri i form av väntan på digitalt lagersaldo och väntan på manuella beräkningar inför beordring. Gotlandsäggs onödiga lagerhållning fastställdes även som ett slöseri och orsakerna till de olika slöserierna identifierades och presenterades i olika Ishikawadiagram. Förbättringsförslagen som studien resulterade i innebar att avskaffa det manuella lagersaldot och att möjliggöra direkt tillgång av det digitala lagersaldot på förpackningsanläggningen i Ruda. Genom att investera i ett system kopplat till det digitala lagersaldot där beräkningarna inför beordring görs automatiskt skulle slöseriet i form av väntan minska. En excelmodell togs även fram som en förbättringsåtgärd till dess att en investering i ett automatiskt system kan göras. För påfyllningar rekommenderades Gotlandsägg att fortsätta beordra fulla transporter men med lägre kvantiteter för varje enskild artikel. En ABC-klassificering genomfördes därför för att underlätta styrningen genom att fokusera på de artiklar som binder mest kapital. Vidare rekommenderades tillämpningen av en högre lagerränta för att undvika onödig lagerhållning i framtiden.
Background: Companies are constantly seeking new ways to design more efficient supply chains and, to ensure profitability, seeks to reduce the costs of production, transportation and inventory. Because inventory related costs account for a large part of the company's total logistics costs, it has come to be the focus of many cost reduction activities. To reduce costs related to inventory while obtaining a desired service level is referred to as inventory control. One way to achieve better inventory control is to locate waste that may exist in the current control. This can be done by establishing a process mapping in order to identify and minimize or eliminate the waste that was identified by giving suggestions of improvement. Purpose: The purpose of this study is to describe Gotlandsägg’s current inventory control of packages for eggs and what costs it results in. Possible waste is then identified in the current inventory control of packages to further on present suggestions on how the inventory control can improve with the goal of reducing costs while still achieve a desired service level. Method: The following essay is a qualitative case study, performed on the company Gotlandsägg AB's packaging plant in Ruda. The study has adopted a deductive standpoint with a positivistic approach. The collection of data contains both primary data, which have been collected through unstructured, structured and semi-structured interviews with staff of Gotlandägg, and secondary data that have been collected from Gotlandsäggs intern systems, Linnaeus University's database and other available literature. v Conclusion: The study has described Gotlandsäggs current replenishment process of their packages for eggs by establishing a process mapping and determined the definable annual cost of inventory management. The current inventory control leads to that the packages are stored for a long time and therefore results in large amounts of tied up capital which increases inventory carrying costs. The process mapping further defined waste in a form of activity that did not create any value to the process, the use of manual inventory levels, as well as waste in the form of waiting for the digital inventory balance and manual calculations to be made before ordering could be performed. Gotlandsägg’s excessive inventory was also identified as a type of waste and the reasons for the types of waste was presented in different Ishikawa-diagrams. The suggestions for improvements concluded to eliminate the manual inventory levels and to allow direct access of the digital inventory levels at the packaging plant in Ruda. By investing in a system that is linked to the inventory levels, where calculations for ordering are made automatically, the waste of waiting could be minimized. An excel model was developed as an improvement until investments in an automated system can be made. For the refills of items, its recommended to control the packaging types in different ways but that all articles should be ordered in minimum order quantity as far as possible. As regarding transport, Gotlandsägg should continue to order full transports but with lower quantities of each article. An ABC-classification was therefore carried out to facilitate the control and to focus on the articles responsible for the most tied up capital. It was also recommended to adopt a higher inventory rate to avoid excessive inventory in the future.

In pursuance of decreasing costs, both the client and the contractor would strive to speed up the construction project. However, accelerating the project schedule will impose additional cost and might be profitable up to a certain limit. Paramount for construction management, analyses of this trade-off between duration and cost is hailed as the time-cost trade-off (TCT) optimization. Inadequacies of existing commercial software packages for such analyses tied with eminence of discretization, motivated development of different paradigms of particle swarm optimizers (PSO) for three extensions of discrete TCT problems (DTCTPs). A sole-PSO algorithm for concomitant minimization of time and cost is proposed which involves minimal adjustments to shift focus to the completion deadline problem. A hybrid model is also developed to unravel the time-cost curve extension of DCTCPs. Engaging novel principles for evaluation of cost-slopes, and pbest/gbest positions, the hybrid SAM-PSO model combines complementary strengths of overhauled versions of the Siemens Approximation Method (SAM) and the PSO algorithm. Effectiveness and efficiency of the proposed algorithms are validated employing instances derived from the literature. Throughout computational experiments, mixed integer programming technique is implemented to introduce the optimal non-dominated fronts of two specific benchmark problems for the very first time in the literature. Another chief contribution of this thesis can be depicted as potency of SAM-PSO model in locating the entire Pareto fronts of the practiced instances, within acceptable time-frames with reasonable deviations from the optima. Possible further improvements and applications of SAM-PSO model are suggested in the conclusion.

In the last decade, the landscape of storage hardware and software has changed considerably. Storage hardware has diversified from hard disk drives and solid state drives to include persistent memory (PMEM) devices such as phase change memory (PCM) and Flash-backed DRAM. On the software side, the increasing adoption of cloud services for building and deploying consumer and enterprise applications is driving the use of cloud storage services. Cloud providers have responded by providing a plethora of choices of storage services, each of which have unique performance characteristics and pricing. We argue this variety represents an opportunity for modern storage systems, and it can be leveraged to improve operational costs of the systems. We propose that storage tiering is an effective technique for balancing operational or de- ployment costs and performance in such modern storage systems. We demonstrate this via three key techniques. First, THMCache, which leverages tiering to conserve the lifetime of PMEM devices, hence saving hardware upgrade costs. Second, CAST, which leverages tiering between multiple types of cloud storage to deliver higher utility (i.e. performance per unit of cost) for cloud tenants. Third, we propose a dynamic pricing scheme for cloud storage services, which leverages tiering to increase the cloud provider's profit or offset their management costs.
Master of Science

This thesis critically examines how the organ trade fits into the anti-trafficking framework, its link to organised crime and the wider political economy. The organ trade involves diverse actors and consists of various practices, including organ trafficking, transplant tourism, organ sales and organ harvesting. Nevertheless, the organ trade is predominantly defined in terms of organ trafficking and discursively framed as a law enforcement issue. Although organ trafficking is considered a major international concern, it is not representative of the phenomenon as a whole. Evidence based research, including empirical work carried out by the author, indicates that the organ trade is better characterised by organ sales and transplant tourism. The majority of individuals who are compelled to sell an organ, for various reasons, do not conform to the elements of trafficking outlined in anti-trafficking legislation, broadly defined under Art 3(a) of the United Nations (2000) Protocol to Prevent, Suppress and Punish Trafficking in Persons. This means that as a consequence of a worldwide prohibition of organ sales, organ sellers are more likely to be prosecuted for committing a criminal offence than recognised and/or assisted as trafficked victims. The core aim of this thesis is to provide a critique of the anti-trafficking framework, explicating the theoretical and practical implications of the prevailing law enforcement model, in response to the organ trade. I argue that co-opting the organ trade into the meta-narrative of human trafficking suspends a wider critique of the phenomenon, linking the emergence of a global market in organs to broader socio-economic conditions and inequalities. Further, I argue that the organ trade is not a direct consequence of a global shortage of organ supplies; rather, it is causally related to the transfer of transplant capabilities to the global South. The rhetorical positioning of the organ trade as an object of law enforcement diverts critical attention away from the transplant industry and the

The principal objective of this research was a critical examination of the Generalised System of Preference schemes as a form of special and differential treatment under the Enabling Clause with specific reference to the complaint brought against the European Union (EU) by India regarding the EU's granting of tariff preferences to developing countries with illegal drug trafficking problem.

Licensing agreements are commonly used when, for instance, exploiting new areas or countries. Trade mark licences are one such example. A trade mark licence gives the proprietor the opportunity to keep its exclusive rights at the same time as another party uses the trade mark in commercial purposes. When licensing an EUTM to a third party, it is possible to include quality control clauses in the agreement in order for the licensor to control that the licensee uses the trade mark correctly. The possibility to include quality control implies that there is no such obligation within EU trade mark law. Yet, in the US, quality control is not only a possibility but also an obligation in order to keep the trade mark registered. Therefore, it is of interest to examine European trade mark law in relation to quality control in licensing. The American view of quality control is examined for illustrative purposes. Within the EU, the essential function of an EUTM means the ability to identify the origin. In addition, one single undertaking is responsible for the quality that is needed for the trade mark to fulfil its essential role in the system of undistorted system. Quality is seen as an economic function of the trade mark and therefore it should not be an obligation to include quality control in trade mark licences. The proprietor should bear the responsibility him- or herself when not including quality control. As a contrast, in the US, the consumers must be protected from deception and therefore it is a requirement for the proprietor to control and maintain the quality by including quality control in trade mark licences. If a trade mark licence does not include quality controls, the licence is considered invalid and the trade mark is considered abandoned. Furthermore, a law and economics perspective is included in the thesis and specifically the theory of TCE and the belonging terms or bounded rationality, opportunism, uncertainty and trust. While the EU seems to value trust more when settling licence agreements, the US seems to value opportunism and uncertainty more due to de fact that consumers must be protected from the proprietors. Since quality control within trade mark licensing appears to lock the proprietor into a situation where it is difficult to differentiate and change the direction of the trade mark, it should not be an obligation to include quality controls in trade mark licences. It should be a privilege for the proprietor to decide on whether to use or not and bear the consequences of that choice.

Доступ до роботи тільки на території бібліотеки ОНЕУ, для переходу натисніть на посилання нижче
У роботі розглядаються теоретичні аспекти сутності та класифікації торгівельних підприємств, дискусійні питання обліку витрат торгівельних підприємств, формування собівартості товарів, теоретичні та практичні аспекти контролю витрат на торгівельних підприємствах. Проаналізовано фінансовий стан ПП «Будівельна оптова база», особливості обліку витрат на підприємстві, систему внутрішнього контролю витрат на підприємстві. Запропоновано відкрити рахунок 29 «Торгова знижка», за рахунками 92 «Адміністративні витрати» та 93 «Витрати на збут» виділити окремі субрахунки, розробити на підприємстві внутрішні стандарти контролю, здійснити його автоматизацію.
The work considers theoretical aspects of the essence and classification of trade enterprises, debatable issues of cost accounting of trade enterprises, the formation of the cost of goods, theoretical and practical aspects of cost control in trade enterprises. Analyzed the financial condition of the company "Construction wholesale base", features of cost accounting at the enterprise, the system of internal control of costs at the enterprise. It is requested to open account 29 "Trade discount", to account 92 "Administrative costs" and 93 "Sales costs" to allocate separate sub-accounts, to develop internal control standards at the enterprise, to automate it.

Guatemala, the most populous country in Central America, is haunted by the legacy of violence, political instability, poverty, corruption, and persisting, relentless inequality. Narco-trafficking routes through Central America became firmly established after air- and sea-based routes were disrupted by U.S. and Mexican drug enforcement efforts in the 1990s. Guatemala and its Central American neighbors were highly vulnerable to incursion by the drug trade, ideally-located between production sources and major consumers, its people and governments weakened by long-standing armed conflict. Evidence shows the drug trade disproportionately impacts Guatemala in comparison to the rest of the region. Its neighbors share similarly well-located geography and the legacy of armed conflicts, but Guatemala lacks the institutional strength and ability to combat the cartels. This paper posits that U.S. prohibitionist policies are ineffective and harmful to Guatemala’s people, based on a supply-reduction model and a review of previous literature and anecdotal evidence. Narco-trafficking and the United States’ drug enforcement efforts, strategies and policies, intensify existing violence, poverty, inequality and corruption within Guatemala, ensnaring its people in a recurring cycle of violence which reinforces barriers to escaping poverty and crime.

Assignment (MEcon)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: The field study reported here examined the importance of branding in the low cost retail industry. Two low cost retailers were identified, who sell boys grey school trousers. The one retailer sells the trousers with a brand name, while the other doesn't sell the grey school trousers with a brand name. Sales volumes of both retailers were drawn for a certain period and questionnaires were developed and sent to the different shops to be completed by the customers to determine how important brands were to them. The results of the research indicated that the retailer selling grey school trousers with a brand name sold more units than the retailer selling the grey school trousers without a brand name. Furthermore, the customers indicated that they would buy grey school trousers with a brand name rather than buying grey school trousers without a brand name,
AFRIKAANSE OPSOMMING: Die navorsing wat hier gerapporteer word, ondersoek die belangrikheid van handelsmerke in die lae-koste kleinhandel industrie. Twee lae-koste kleinhandelaars is geidentifiseer wat grys skool langbroeke vir seuns verkoop. Die een kleinhandelaar verkoop die grys skoollangbroek met 'n handelsnaam, terwyl die ander kleinhandelaar nie die broek met 'n handelsnaam verkoop nie. Verkoopsvolume data vir 'n sekere periode is van beide kleinhandelaars getrek en vraelyste is ontwikkel en na die winkels gestuur. Die klient moes die vraelys voltooi om te bepaal hoe belangrik handelsmerke vir die klient is. Die resultate van die studie het daarop gedui dat die kleinhandelaar wat die grys skool langbroek met die handelsmerk verkoop, meer eenhede verkoop het as die kleinhandelaar wat die grys skool langbroek sonder handelsmerk verkoop. Verder het die klient aangedui dat die grys skool langbroek met 'n handelsnaam eerder gekoop sal word as 'n grys skoollangbroek sonder handelsmerk.

Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, December 2007.
Thesis Advisor(s): Looney, Robert. "December 2007." Description based on title screen as viewed on January 18, 2008. Includes bibliographical references (p. 73-76). Also available in print.

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Cost of debt is a key cognitive anchor for managerial decisions and an important determinant of firm profitability. We extend international management research by analyzing the effects of institutional distance, institutional quality, and their dynamics on the cost of debt in the context of foreign direct investments (FDI). We test our conceptual model on a sample of companies making 3,764 greenfield foreign direct investments from developed into less developed markets. Using hierarchical linear modelling, we show that the financial consequences of internationalizing into countries with weak institutions depend on both the institutional distance between countries, as well as their institutional quality. Furthermore, we find that recent changes in institutional quality form expectations about future development and ultimately influence post investment financing costs.

This thesis examines parental condition, how it is traded off against reproduction and how it is displayed in a secondary sexual trait. The studies were performed on nest-box breeding collared flycatchers Ficedula albicollis on the island of Gotland, in the Baltic Sea. Early breeding and high fitness were found to be associated with high levels of glycosylated haemoglobin possibly governed by migratory exertion and infectious disease. In order to test if immune function is expressed in secondary sexual traits and how it is traded off against reproductive effort a series of experiments were performed, in which birds were challenged with an antigen, via a vaccine containing neutralised paramyxovirus. The forehead patch of the male collared flycatcher serves as a badge of status and is under sexual selection. Good condition, as reflected in strong immune response and low levels of blood parasites was found to be associated with bigger patch size. Patch size was also found to vary in size within the same breeding season in a pattern predictable from immune response data. Immune response, in itself, was found to be costly in terms of reduced survival, confirming that trade-offs involving suppression of immune response may increase fitness. Mating effort was found to be traded off against immune function and moult. Experimental brood size manipulations revealed a trade-off females between number of offspring and immune function. Thus I suggest a set of parameters useful for condition estimation. I also show that immune response is costly and, second, that pathogen resistance probably plays an important role in the shaping of secondary sexual traits and life-history decisions.