<p>This thesis addresses the issue of weighted cost-benefit analysis (WCBA). WCBA is a welfare evaluation model where income distribution effects are valued by distributional weighting. The method was developed already in the 1970s. The interest in and applications of this method have increased in the past decade, e.g. when evaluating of global environmental problems. There are, however, still unsolved problems regarding the application of this method. One such issue is the choice of the approach to the means of estimating of the distributional weights. The literature on WCBA suggests a couple of approaches, but gives no clues as to which one is the most appropriate one to use, either from a theoretical or from an empirical point of view. Accordingly, the choice of distributional weights may be an arbitrary one. In the first paper in this thesis, the consequences of the choice of distributional weights on project decisions have been studied. Different sets of distributional weights have been compared across a variety of strategically chosen income distribution effects. The distributional weights examined are those that correspond to the WCBA approaches commonly suggested in literature on the topic. The results indicate that the choice of distributional weights is of importance for the rank of projects only when the income distribution effects concern target populations with low incomes. The results also show that not only the mean income but also the span of incomes, of the target population of the income distribution effect, affects the result of the distributional weighting when applying very progressive non-linear distributional weights. This may cause the distributional weighting to indicate an income distribution effect even though the project effect is evenly distributed across the population.</p><p>One rational for distributional weighting, commonly referred to when applying WCBA, is that marginal utility of income is decreasing with income. In the second paper, this hypothesis is tested. My study contributes to this literature by employing stated preference data on compensated variation (CV) in a model flexible as to the functional form of the marginal utility. The results indicate that the marginal utility of income decreases linearly with income.</p><p>Under certain conditions, a decreasing marginal utility of income corresponds to risk aversion. Thus the hypothesis that marginal utility of income is decreasing with income can be tested by analyses of individuals’ behaviour in gambling situations. The third paper examines of the role of risk aversion, defined by the von Neumann-Morgenstern expected utility function, for people’s concern about the problem of ‘sick’ buildings. The analysis is based on data on the willingness to pay (WTP) for having the indoor air quality (IAQ) at home examined and diagnosed by experts and the WTP for acquiring an IAQ at home that is guaranteed to be good. The results indicate that some of the households are willing to pay for an elimination of the uncertainty of the IAQ at home, even though they are not willing to pay for an elimination of the risks for building related ill health. The probability to pay, for an elimination of the uncertainty of the indoor air quality at home, only because of risk aversion is estimated to 0.3-0.4. Risk aversion seems to be a more common motive, for the decision to pay for a diagnosis of the IAQ at home, among young people.</p><p>Another rationale for distributional weighting, commonly referred to, is the existence of unselfish motives for economic behaviour, such as social inequality aversion or altruism. In the fourth paper the hypothesis that people have altruistic preferences, i.e. that they care about other people’s well being, is tested. The WTP for a public project, that ensures good indoor air quality in all buildings, have been measured in three different ways for three randomly drawn sub-samples, capturing different motives for economic behaviour (pure altruism, paternalism and selfishness). The significance of different questions, and different motives, is analysed using an independent samples test of the mean WTPs of the sub-samples, a chi-square test of the association between the WTP and the sample group membership and an econometric analysis of the decision to pay to the public project. No evidence for altruism, either pure altruism or paternalism, is found in this study.</p>

Eine der stärksten Erweiterungen der klassischen Theorie formaler Sprachen und Automaten ist die Einbeziehung von Gewichten oder Vielfachheiten aus einem Halbring. Diese Dissertation untersucht gewichtete Automaten über Strukturen mit Nebenläufigkeit. Wir erweitern die Arbeit von Lodaya und Weil und erhalten so ein Modell gewichteter verzweigender Automaten, in dem die Berechnung des Gewichts einer parallelen Komposition anders als die einer sequentiellen Komposition gehandhabt wird. Die von Lodaya und Weil eingeführten Automaten modellieren Nebenläufigkeit durch Verzweigen. Ein verzweigender Automat ist ein endlicher Automat mit drei verschiedenen Typen von Transitionen. Sequentielle Transitionen überführen durch Ausführen eines Ereignisses einen Zustand in einen anderen. Dagegen sind Gabel- und Binde-Transitionen für das Verzweigen verantwortlich. Läufe dieser Automaten werden beschrieben durch sequentiell-parallele posets, kurz sp-posets. Alle Transitionen des Automaten werden in unserem Modell mit Gewichten versehen. Neben dem Nichtdeterminismus und der sequentiellen Komposition wollen wir nun auch die parallele Komposition quantitativ behandeln. Dafür benötigen wir eine Gewichtsstruktur mit einer Addition, einer sequentiellen und einer parallelen Multiplikation. Solch eine Struktur, genannt Bihalbring, besteht damit de facto aus zwei Halbringen mit derselben additiven Struktur. Weiterhin muss die parallele Multiplikation kommutativ sein. Das Verhalten eines gewichteten verzweigenden Automaten ist dann eine Funktion, die jeder sp-poset ein Element eines Bihalbrings zuordnet. Das Hauptresultat charakterisiert das Verhalten dieser Automaten im Sinne von Kleenes und Schützenbergers Sätzen über das Zusammenfallen der Klassen der erkennbaren und der rationalen Sprachen bzw. formalen Potenzreihen. Darüber hinaus untersuchen wir den Abschluss dieser Verhalten unter allen rationalen Operationen und unter dem Hadamard-Produkt. Letztlich diskutieren wir Zusammenhänge zwischen Reihen und Sprachen im Rahmen verzweigender Automaten. / One of the most powerful extensions of classical formal language and automata theory is the consideration of weights or multiplicities from a semiring. This thesis investigates weighted automata over structures incorporating concurrency. Extending work by Lodaya and Weil, we propose a model of weighted branching automata in which the calculation of the weight of a parallel composition is handled differently from the calculation of the weight of a sequential composition. The automata as proposed by Lodaya and Weil model concurrency by branching. A branching automaton is a finite-state device with three different types of transitions. Sequential transitions transform a state into another one by executing an action. In contrast, fork and join transitions are responsible for branching. Executions of such systems can be described by sequential-parallel posets, or sp-posets for short. In the model considered here all kinds of transitions are equipped with weights. Beside non-determinism and sequential composition we would like to deal with the parallel composition in a quantitative way. Therefore, we are in need of a weight structure equipped with addition, a sequential, and, moreover, a parallel multiplication. Such a structure, called a bisemiring, is actually composed of two semirings with the same additive structure. Moreover, the parallel multiplication has to be commutative. Now, the behavior of a weighted branching automaton is a function that associates with every sp-poset an element from the bisemiring. The main result characterizes the behavior of these automata in the spirit of Kleene's and Schützenberger's theorems about the coincidence of recognizable and rational languages, and formal power series, respectively. Moreover, we investigate the closure of behaviors under all rational operations and under Hadamard-product. Finally, we discuss connections between series and languages within our setting.

This thesis addresses the issue of weighted cost-benefit analysis (WCBA). WCBA is a welfare evaluation model where income distribution effects are valued by distributional weighting. The method was developed already in the 1970s. The interest in and applications of this method have increased in the past decade, e.g. when evaluating of global environmental problems. There are, however, still unsolved problems regarding the application of this method. One such issue is the choice of the approach to the means of estimating of the distributional weights. The literature on WCBA suggests a couple of approaches, but gives no clues as to which one is the most appropriate one to use, either from a theoretical or from an empirical point of view. Accordingly, the choice of distributional weights may be an arbitrary one. In the first paper in this thesis, the consequences of the choice of distributional weights on project decisions have been studied. Different sets of distributional weights have been compared across a variety of strategically chosen income distribution effects. The distributional weights examined are those that correspond to the WCBA approaches commonly suggested in literature on the topic. The results indicate that the choice of distributional weights is of importance for the rank of projects only when the income distribution effects concern target populations with low incomes. The results also show that not only the mean income but also the span of incomes, of the target population of the income distribution effect, affects the result of the distributional weighting when applying very progressive non-linear distributional weights. This may cause the distributional weighting to indicate an income distribution effect even though the project effect is evenly distributed across the population. One rational for distributional weighting, commonly referred to when applying WCBA, is that marginal utility of income is decreasing with income. In the second paper, this hypothesis is tested. My study contributes to this literature by employing stated preference data on compensated variation (CV) in a model flexible as to the functional form of the marginal utility. The results indicate that the marginal utility of income decreases linearly with income. Under certain conditions, a decreasing marginal utility of income corresponds to risk aversion. Thus the hypothesis that marginal utility of income is decreasing with income can be tested by analyses of individuals’ behaviour in gambling situations. The third paper examines of the role of risk aversion, defined by the von Neumann-Morgenstern expected utility function, for people’s concern about the problem of ‘sick’ buildings. The analysis is based on data on the willingness to pay (WTP) for having the indoor air quality (IAQ) at home examined and diagnosed by experts and the WTP for acquiring an IAQ at home that is guaranteed to be good. The results indicate that some of the households are willing to pay for an elimination of the uncertainty of the IAQ at home, even though they are not willing to pay for an elimination of the risks for building related ill health. The probability to pay, for an elimination of the uncertainty of the indoor air quality at home, only because of risk aversion is estimated to 0.3-0.4. Risk aversion seems to be a more common motive, for the decision to pay for a diagnosis of the IAQ at home, among young people. Another rationale for distributional weighting, commonly referred to, is the existence of unselfish motives for economic behaviour, such as social inequality aversion or altruism. In the fourth paper the hypothesis that people have altruistic preferences, i.e. that they care about other people’s well being, is tested. The WTP for a public project, that ensures good indoor air quality in all buildings, have been measured in three different ways for three randomly drawn sub-samples, capturing different motives for economic behaviour (pure altruism, paternalism and selfishness). The significance of different questions, and different motives, is analysed using an independent samples test of the mean WTPs of the sub-samples, a chi-square test of the association between the WTP and the sample group membership and an econometric analysis of the decision to pay to the public project. No evidence for altruism, either pure altruism or paternalism, is found in this study.

The Blue Penguin (Eudyptula minor) is assumed to be declining over much of its range, largely due to introduced predators. Anecdotal evidence suggests that one of the areas of declining population is the West Coast of the South Island. The purpose of this study was to determine the reasons for the assumed decline of blue penguins in South Westland. This was done by studying breeding ecology at several blue penguin colonies to assess the importance of breeding success and adult mortality on the penguin population. Three blue penguin colonies in South Westland, at Five Mile and Three Mile beaches south of Okarito, and at the Wanganui River mouth near Harihari, were monitored throughout the 2008/09 breeding season. During each burrow visit the number of eggs and chicks were recorded as well as the date of laying, hatching or fledging. Five colonies of blue penguin were also monitored in Buller over the same breeding season in a study conducted by the West Coast Blue Penguin Trust, a community trust based on the West Coast. The results of both studies were compared to determine the effect of predator control on breeding parameters, such as breeding success. Of 137 eggs laid in South Westland, 108 chicks survived until fledging, giving an overall breeding success of 78.8%. In Buller, 64 chicks survived to fledging from 101 eggs laid, resulting in an overall breeding success of 63.4%. Breeding success was significantly higher at penguin colonies in South Westland, compared to the Buller colonies. There was no evidence that predator control had an effect on breeding success in South Westland or Buller. The mean number of chicks fledged per pair that produced eggs was 1.55 in South Westland and 1.16 in Buller. The overall proportion of occupied breeding burrows compared to the total number of suitable burrows at the South Westland sites was 73.8% (n = 103). At the Buller sites, only 60.3 % (n = 151) of the total number of burrows was occupied. Road kills are a major threat to blue penguins in Buller due to the proximity of colonies to the state highway. Fortunately, incidences of road death in South Westland are rare and due to the distance from roads, do not pose a significant threat to South Westland blue penguins. Further study of blue penguin colonies in South Westland is needed to learn more about annual variation in breeding productivity and to determine if breeding success is consistently high over an extended time period. If this is the case, then the cause of blue penguin decline on the West Coast is unlikely to be due to problems with breeding as the breeding success during this study is one of the highest recorded for blue penguins. Although there was no apparent effect of predator control on breeding productivity during this study there is evidence from other locations that predators, in particular stoats, have contributed to the decline of blue penguin populations. More research into the impact of predators on penguins over a longer period of time is needed on the West Coast before a change is made to how predators are managed.

Made available in DSpace on 2014-12-17T15:47:44Z (GMT). No. of bitstreams: 1 RaulBP.pdf: 1811907 bytes, checksum: 007d54350318472b95b8e06144b749a5 (MD5) Previous issue date: 2007-07-27 / Although some individual techniques of supervised Machine Learning (ML), also known as classifiers, or algorithms of classification, to supply solutions that, most of the time, are considered efficient, have experimental results gotten with the use of large sets of pattern and/or that they have a expressive amount of irrelevant data or incomplete characteristic, that show a decrease in the efficiency of the precision of these techniques. In other words, such techniques can t do an recognition of patterns of an efficient form in complex problems. With the intention to get better performance and efficiency of these ML techniques, were thought about the idea to using some types of LM algorithms work jointly, thus origin to the term Multi-Classifier System (MCS). The MCS s presents, as component, different of LM algorithms, called of base classifiers, and realized a combination of results gotten for these algorithms to reach the final result. So that the MCS has a better performance that the base classifiers, the results gotten for each base classifier must present an certain diversity, in other words, a difference between the results gotten for each classifier that compose the system. It can be said that it does not make signification to have MCS s whose base classifiers have identical answers to the sames patterns. Although the MCS s present better results that the individually systems, has always the search to improve the results gotten for this type of system. Aim at this improvement and a better consistency in the results, as well as a larger diversity of the classifiers of a MCS, comes being recently searched methodologies that present as characteristic the use of weights, or confidence values. These weights can describe the importance that certain classifier supplied when associating with each pattern to a determined class. These weights still are used, in associate with the exits of the classifiers, during the process of recognition (use) of the MCS s. Exist different ways of calculating these weights and can be divided in two categories: the static weights and the dynamic weights. The first category of weights is characterizes for not having the modification of its values during the classification process, different it occurs with the second category, where the values suffers modifications during the classification process. In this work an analysis will be made to verify if the use of the weights, statics as much as dynamics, they can increase the perfomance of the MCS s in comparison with the individually systems. Moreover, will be made an analysis in the diversity gotten for the MCS s, for this mode verify if it has some relation between the use of the weights in the MCS s with different levels of diversity / Apesar de algumas t?cnicas individuais de Aprendizado de M?quina (AM) supervisionado, tamb?mconhecidos como classificadores, ou algoritmos de classifica??o, fornecerem solu??es que, na maioria das vezes, s?o consideradas eficientes, h? resultados experimentais obtidos com a utiliza??o de grandes conjuntos de padr?es e/ou que apresentam uma quantidade expressiva de dados incompletos ou caracter?sticas irrelevantes, que mostram uma queda na efic?cia da precis?o dessas t?cnicas. Ou seja, tais t?cnicas n?o conseguem realizar um reconhecimento de padr?es de uma forma eficiente em problemas complexos. Com o intuito de obter um melhor desempenho e efic?cia dessas t?cnicas de AM, pensouse na id?ia de fazer com que v?rios tipos de algoritmos de AM consigam trabalhar conjuntamente, dando assim origem ao termo Sistema Multi-Classificador (SMC). Os SMC s apresentam, como componentes, diferentes algoritmos de AM, chamados de classificadores base, e realizam uma combina??o dos resultados obtidos por estes algoritmos para atingir o resultado final. Para que o SMC tenha um desempenho melhor que os classificadores base, os resultados obtidos por cada classificador base devem apresentar uma determinada diversidade, ou seja, uma diferen?a entre os resultados obtidos por cada classificador que comp?em o sistema. Pode-se dizer que n?o faz sentido ter SMC s cujos classificadores base possuam respostas id?nticas aos padr?es apresentados. Apesar dos SMC s apresentarem melhores resultados que os sistemas executados individualmente, h? sempre a busca para melhorar os resultados obtidos por esse tipo de sistema. Visando essa melhora e uma maior consist?ncia nos resultados, assim como uma maior diversidade dos classificadores de um SMC, v?m sendo recentemente pesquisadas metodologias que apresentam como caracter?sticas o uso de pesos, ou valores de con- fian?a. Esses pesos podem descrever a import?ncia que um determinado classificador forneceu ao associar cada padr?o a uma determinada classe. Esses pesos ainda s?o utilizados, em conjunto com as sa?das dos classificadores, durante o processo de reconhecimento (uso) dos SMC s. Existem diferentes maneiras de se calcular esses pesos e podem ser divididas em duas categorias: os pesos est?ticos e os pesos din?micos. A primeira categoria de pesos se caracteriza por n?o haver a modifica??o de seus valores no decorrer do processo de classifica??o, ao contr?rio do que ocorre com a segunda categoria, onde os valores sofrem modifica??es no decorrer do processo de classifica??o. Neste trabalho ser? feito uma an?lise para verificar se o uso dos pesos, tanto est?ticos quanto din?micos, conseguem aumentar o desempenho dos SMC s em compara??o com estes sistemas executados individualmente. Al?m disso, ser? feita uma an?lise na diversidade obtida pelos SMC s, para dessa forma verificar se h? alguma rela??o entre o uso dos pesos nos SMC s com diferentes n?veis de diversidade

Made available in DSpace on 2016-06-02T20:20:26Z (GMT). No. of bitstreams: 1 TeseTBM.pdf: 401834 bytes, checksum: fba52ede0a39e98b173078af1f5a85d5 (MD5) Previous issue date: 2006-10-20 / Financiadora de Estudos e Projetos / The objective in this study was to estimate genetic parameters for the traits days to calving (DC), days to first calving (DFC) and gestation length (GL), associated with reproductive performance of females, as well as to evaluate the relationships of DC and DFC with scrotal circumference at 12 months of age (SC12) and body weights at 12 months of age (W12), at calving (WC), at first calving (WFC), at beginning of the breeding season (WBS) and at beginning of the first breeding season (WFBS), and of GL with weight at birth (BW) and W12. Analyses were done using animal models and the derivative free restricted maximum likelihood methodology. Estimates of heritabilities varied from 0.02 to 0.09 for DC, from 0.15 to 0.23 for DFC and from 0.04 to 0.41 for GL, depending on the data set and the model used for each trait. Genetic correlations of DC and DFC with SC12 showed that it is possible to improve these female reproductive traits by selecting for increase in SC12. With respect to W12, selection to increase this trait should not produce significant changes in DC, but may increase DFC. Associations of the other female body weights with DFC and DC indicated that heavier females experience lower reproductive performance. Estimates of genetic correlations of GL with BW and W12 indicated that selection to change GL will result in correlated response in BW with no changes in W12. / O objetivo neste estudo foi estimar parâmetros genéticos para as características dias para o parto (DP), dias para o primeiro parto (DPP) e período de gestação (PG), associadas ao desempenho reprodutivo de fêmeas, bem como avaliar as relações de DP e DPP com o perímetro escrotal aos 12 meses de idade (PE12) e os pesos aos 12 meses de idade de machos e fêmeas (P12), ao parto (PVP), ao primeiro parto (PVPP), à entrada da estação de monta (PEM) e à entrada da primeira estação de monta (PEPM), e do PG com o peso do bezerro ao nascimento (PN) e com P12. As análises foram realizadas utilizando modelos animais e o método da máxima verossimilhança restrita livre de derivadas. As estimativas de herdabilidade variaram de 0,02 a 0,09 para DP, de 0,15 a 0,23 para DPP e de 0,04 a 0,41 para PG, dependendo do arquivo e do modelo utilizados para cada característica. As correlações genéticas de DP e DPP com PE12 mostraram que é possível obter melhoria das características reprodutivas de fêmeas selecionando-se para aumento de PE12. Com relação a P12, a seleção para aumentar essa característica não deve gerar resposta significativa em DP, mas pode aumentar DPP. A avaliação das associações dos demais pesos de fêmeas com DPP e DP indicou que fêmeas maiores apresentam pior desempenho reprodutivo. As correlações genéticas do PG com PN e com P12 mostraram que a utilização de PG como critério de seleção resulta em resposta correlacionada em PN sem alterar P12.

Made available in DSpace on 2016-06-02T20:27:36Z (GMT). No. of bitstreams: 1 1610.pdf: 953018 bytes, checksum: 71de779ec49ee3cef03c3060c45a97f3 (MD5) Previous issue date: 2007-11-20 / Financiadora de Estudos e Projetos / In this work, we will study the existence and nonexistence of positive weak solutions for two classes of elliptic systems with weights. The first class will involve nonlinearities of the type positone and semipositone. We will prove a strong maximum principle, and we will obtain some properties of the first eigenfunction of the eigenvalue problem associated to our operator, and also we will prove the sub and supersolution method. The second class will involve a nonlinear perturbation. We will use the variational methods to study the subcritical and critical situations, and under certain hypotheses, we will show the existence of a second weak solution. / Neste trabalho, estudaremos a existência e inexistência de solução fraca positiva para duas classes de sistemas elípticos com pesos. A primeira classe envolverá não linearidades do tipo positônico e semipositônico. Provaremos um princípio de máximo forte, e obteremos algumas propriedades da primeira autofunção do problema de autovalor associado ao nosso operador, e também provaremos o método de sub e supersolução. A segunda classe que consideraremos terá uma perturbação não linear. Usaremos os métodos variacionais para estudar tanto a situação subcrítica quanto à situação crítica, e sob certas hipóteses, mostraremos a existência de uma segunda solução fraca.

Introdução: há vários relatos na literatura que referem o aumento progressivo da obesidade em mulheres de nível sócio-econômico baixo das áreas urbanas. Os fatores que podem estar relacionados à transição nutricional nesse estrato da sociedade ainda são muito controversos. Este estudo tem por objetivo avaliar a freqüência de obesidade, e fatores associados em mulheres numa área de exclusão social da cidade de São Paulo. Métodos: foi realizado um estudo transversal, entre o período de junho de 2002 a abril de 2004, em 116 mulheres moradoras de favelas na periferia e região metropolitana de São Paulo. O desfecho antropométrico primário foi o índice de massa corpórea (IMC). As mulheres foram categorizadas em três estratos de índice de massa corpórea [IMC] (= 25.0 kg/m2; 25.0 to 29.9 kg/m2; and = 30.0 kg/m2). Os grupos foram comparados entre si, quanto às características referentes às variáveis de provável exclusão social, hábitos de vida e clínico laboratoriais (medidas antropométricas e fatores de risco cardiovasculares). O modelo logístico usado analisou as variáveis independentes associadas ao sobrepeso e obesidade. Resultados: a freqüência de obesidade nessa amostra (28.4%), foi maior que a observada em outros estudos brasileiros. Após o ajuste multivariado, comparadas às mulheres magras (IMC < 25 kg/m2), as que possuíam história de três ou mais partos foram mais sobrepeso (Razão de chance [RC], 3.4; 95% Intervalo de confiança [95% IC], 1.2-9.6) e obesas (razão de chance [RC], 5,3; 95% Intervalo de confiança [95% IC], 1,6-17,5). Mulheres brancas comparadas com o grupo de referência (magras e negras) foram mais obesas. (RC, 9.9; 95% IC, 1.5-64.6). Comparadas às magras, mulheres obesas apresentaram maiores níveis de dislipidemia por HDL-colesterol baixo (RC, 10; IC 95%, 2.5-50) e hipertrigliceridemia (RC, 8.4; IC95%, 1.5-48). Nessas mulheres de baixo nível sócio-econômico, paridade e raça foram os mais importantes fatores associados à obesidade. Mulheres com cor da pele branca foram claramente mais obesas que as de cor negra e parda. / To evaluate the prevalence and associated risk factors for obesity in low-income women living in a metropolitan area of the city of São Paulo. Methods: Cross-sectional study (116 women) living in slums. Women were categorized in three body-mass index strata [BMI] (=25.0 kg/m 2 ; 25 to 29.9 kg/m2; and = 30.0 kg/m2). Groups were compared regarding variables of social inequalities and clinical assessment: anthropometric measurements and cardiovascular risk factors. A logistic model was used to analyze the independent variables associated with overweight and obesity. Results: Frequency of obesity of 28.4% was higher than in other Brazilian samples. After multivariate adjustment, compared to lean, women with three or more childbearing were more overweight (Odds Ratio [OR], 3.4; 95% Confidence Interval [95% CI], 1.2-9.6) and obese (Odds Ratio [OR], 5,3; 95% Confidence Interval [95% CI], 1,6-17,5). White women compared to reference group (lean and African American women) were also more obese. (OR, 9.9; 95% CI, 1.5-64.6). Compared to lean, obese women had lower HDL-cholesterol levels (OR, 10; 95% CI, 2.5-50) and hypertriglyceridemia (OR, 8.4; 95% CI, 1.5-48). In these low-income women, parity and race were the most important factors associated to obesity. White women were clearly more obese than mullato and African American women.

Magister Administrationis - MAdmin / Through South African labour legislation, bargaining councils are empowered to conclude collective agreements between employers and trade unions. While bargaining councils were created for virtually every sector within the South African private sector, only one bargaining council exists for the public sector. This public sector bargaining council is known as the Public Service Co-ordinating Bargaining Council (PSCBC). The PCSBC subsequently established four sectoral councils to further collectively bargain on matters pertaining to sectoral issues relevant to the sector it represents. However, the PSCBC remains the apex of these four public service sectoral bargaining councils. This thesis focuses on how the Public Service Co-ordinating Bargaining Council (PSCBC) contributes to social dialogue within South African public service. This thesis seeks to fill a significant literature gap on collective bargaining as accomplished by the PSCBC. The thesis briefly examines the history of collective bargaining in the South African public service. The research methodology utilised includes information gleaned from annual reports published by the PSCBC. Interviews of selected stakeholders such as government officials and labour organisations involved in the PSCBC were conducted. The PSCBC objectives are identified and analysed against the performance of the PSCBC for the period 1997 to 2007. The relevant PSCBC role players are identified. The power realities between these role players are reflected. The criteria for remaining a party to these PSCBC will be explained. The thesis holds that historically an adversarial relationship existed between the state as employer and the recognised trade unions. The establishment of the PSCBC created the opportunity for the historical adversaries between an employer and trade union to be converted into social dialogue interactions, which are commonly believed to be a better approach in resolving their differences. / South Africa

Scheduling has always been an indispensable part of resource allocation in wireless networks. Accurate information about channel-state is assumed as a modeling simplification. However, in a real-life network ,e.g., Long Term Evolution(LTE) or IEEE 802.16e WiMAX, the channel-state information feedback to the transmitter can have uncertainty. The primary reason being that although resource allocation is done at the finer granularity of a Physical Resource Block (PRB), channel-state information is still feedback at the coarser granularity of a sub band, which is a group of PRBs. This is done to reduce the feedback traffic from the users to the Base Station. However, this averaging causes information loss and hence, the resulting uncertainty at the scheduler. Moreover, uncertainty might be present in the channel-estimates because of the very process of estimation. In the first part of the thesis, we model the channel-estimate in accuracy and characterize the network stability region. Compared to earlier works, we allow the channel estimates to have dependence among themselves, which is a more realistic situation in a modern LTE or WiMax network. We then propose two simple Max Weight based scheduling schemes that achieve any rate in the interior of the stability region. We also derive an asymptotically tight upper bound on the mean queueing delay in our system under one of the throughput-optimal policies we propose. The above policies ensure stability of the network and we have also obtained bounds on the mean queueing delays. However, different applications may require certain quality of service which may not be satisfied by these policies. Thus, we also propose a throughput-optimal policy for the network under traffic with heterogeneous QoS constraints and present some numerical results studying its performance. In the second part of the thesis, we study the problem of energy-efficient scheduling under average delay constraint. For wireless access technologies, the largest power consumer is the Base Station(BS). Any reduction in the power consumption in a BS will reduce carbon footprint from the Information and Communication Technology sector. We concentrate on the problem of minimizing the total non-renewable power consumed in a Green BS, that is powered by renewable energy sources ,e.g., solar/wind energy and may also be connected to the power grid or diesel generators. Specifically, we consider the problem of minimizing the average grid power consumption of a Green BS downlink in scheduling multiple users with average delay constraints. We have a packetized model for the data packets (i.e., the packets cannot be fragmented) which is a more realistic model for packet-switched networks. The power function is a non-decreasing convex function of the queue-lengths and only one user is allowed to transmit in a slot. We prove the existence of a power optimal policy under delay constraints for multiple users. We analyse the problem and provide some structural results for the optimal policy.