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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Swedish consumers say: -" Subliminal marketing is smart marketing!"

Hedgren, Vickie, Persson, Angelica January 2015 (has links)
Title: Swedish consumers say – ”Subliminal marketing is smart marketing!” Authors: Vickie Hedgren and Angelica Persson Adviser: Klaus Solberg Søilen Level: Dissertation in Marketing, 15 ECTS, Spring 2015 Keywords: Subliminal, Messages, Advertising, Advertisement, Neuromarketing, Psychology, Subconscious, Primal instincts, Subliminal techniques, Ethics, Acceptance, Emotional Connection Purpose: The purpose of this dissertation is to find out what Swedish consumers think about marketing that is meant to influence their subconscious in their decision making, with a focus on subliminal messages, and whether it is ethically acceptable. This will be carried out by examining the two following research questions: 1. What marketing methods aimed at building a psychological connection with the consumer are ethically acceptable and in what areas of marketing or situations? 2. Is it ethical to use subliminal marketing for a cause-related brand, a luxury brand or aimed at a specific income group? We will further examine theories and studies done over the years as well as carry out our own to come up with our conclusions. Frame of Reference: We start of by presenting overall theories regarding subliminal advertising which leads us to various breakdowns such as psychology, primal instincts, subliminal techniques, ethics, causerelated marketing, high- and low end consumers. Methodology: The dissertation is based on a combination of quantitative and qualitative studies. We conducted one survey with 200 respondents and two interviews with marketers. We bring up the importance of validity, reliability, generalizability, carefulness and criticism. Empirical Framework: We will present the collected data from the performed online survey as well as the information from the two personal interviews. Conclusion: Swedish consumers have a high level of ethical acceptance when it comes to marketing that is meant to create a psychological connection. The conclusions made are that 1. Out of the 14 methods we chose to include in our dissertation, 12 of them had a high level of ethical acceptance; subliminal messages in fashion advertising and in an active situation is ethical 2. It is more unethical if a good-cause company uses subliminal marketing than if a luxury brand uses it.
22

Constructing an Index Fund Using Interior Point Primal- Dual Method

Celestin, Kamta, Galabe, Sampid Marius January 2011 (has links)
Optimization methods nowadays play a very important role in financial decisions such as portfolio managements, construction of index funds and pension funds.  This Master Thesis is devoted to the problem of an index fund construction. The problem is represented as a linear optimization problem of re-balancing the portfolio at minimum cost and solved using the Primal-Dual interior point method. The index fund is constructed using ten companies from the Dow Jones Industrial Average Index (DJIA). The Primal-Dual interior point method was first implemented in Matlab and later on in Java.
23

Desempenho, composição da carcaça e características de qualidade da carne de suínos de diferentes genótipos

Monteiro, José Mauro Costa [UNESP] 30 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-30Bitstream added on 2014-06-13T20:05:38Z : No. of bitstreams: 1 monteiro_jmc_dr_jabo.pdf: 1222391 bytes, checksum: acc3bc476ca5877b6c0800b21ad83071 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivou-se comparar genótipos de suínos relativos ao desempenho, parâmetros e características de carcaça e da carne em animais abatidos aos 161 dias de idade. Utilizaram-se os seguintes genótipos: G1 - ½ Topigs© (Toppi) x ½ Naïma®; G2 - ½ DB Danbred© (Frederik) x ½ Naïma®; G3 - ½ PIC© (AGPIC 412) x ½ Naïma®; G4 - ½ SG 2030© (Duroc) x ½ Naïma®; e G5 - ½ Pen Ar Lan© (P76) x ½ Naïma®. Estudaram-se o ganho de peso total (GPT), consumo de ração total (CRT), conversão alimentar (CA) e eficiência alimentar (EA). As meias carcaças esquerdas foram, inicialmente, avaliadas quanto ao peso da carcaça quente (PCQ) e fria (PCF), comprimento (CC), área do olho de lombo (AOL), comprimento de olho do lombo (COL) e profundidade do toucinho (PT10ª). Foram feitas ainda, com a pistola de tipificação eletrônica Hennessy, medidas de espessura do músculo (EM1 e EM2) e profundidade do toucinho (PT1 e PT2). Foram feitas medidas de espessura de toucinho na altura da primeira costela (ET1), última costela (ET2), última lombar (ET3) e máxima lombar (ETM), com o auxílio de paquímetro digital. A carcaça foi desdobrada em seus cortes primários: pernil, carré, barriga, barriga ventral, fraldinha, paleta, sobre paleta, ponta do peito, filezinho, antebraço, perna e papada. Após a pesagem desses cortes, foi realizada a desossa dos mesmos, para se determinar os pesos da carne, gordura interna, ossos, pele e gordura subcutânea de cada um. A porcentagem de carne magra (PCM) foi determinada dividindo-se o total de carne magra desossada pelo peso da carcaça fria. Foram estudados os seguintes parâmetros físico-químicos da carne: pH post-mortem, perda de líquido por gotejamento, cor da carne,... / The aim of this work it was to compare different swine genotypes with the performance, characteristics of carcass and meat quality in swine slaughtered at 161 days of age. The following genotypes had been used: G1 - ½ Topigs© (Toppi) x ½ Naïma©; G2 - ½ DB Danbred© (Frederik) x ½ Naïma©; G3 - ½ PIC© (AGPIC 412) x ½ Naïma©; G4 - ½ SG 2030© (Duroc) x ½ Naïma©; e G5 - ½ Pen Ar Lan© (P76) x ½ Naïma©. They had been studied the profit of all up weight (BW), consumption of total ration (CTR), feed conversion (FC) and alimentary efficiency (AE). The half left carcasses had been, initially, evaluated to the hot carcass weight (HCW) and cold weight (CCW), carcass length (CL), loin eye area (LEA), loin eye length (LEL) and backfat thickness in tenth rib (BT10th). They had been made still, with the pistol electronic Hennessy, measures of muscle depth (MD1 and MD2) and fat depth (FD1 and FD2). Backfat thickness was measured at four locations: in the first rib (BT1), last rib (BT2), last lumbar (BT3) and maximum lumbar (BTM), with digital paquimeter. The carcass was unfolded in these cuts: ham, loin, belly, ventral belly, cranial belly, shoulder, neck, jowl, tenderloin, front shank, hind shank and cheek. After the weight of these cuts, the composition of each one was determined by physical dissection into lean, fat, bone, and skin. The lean meat percentage (LMP) was determined, dividing the total of boned lean meat by the weight of the cold carcass. The following parameters had been studied in the meat: pH post-mortem, ...(Complete abstract click electronic access below)
24

Sublinear-Time Learning and Inference for High-Dimensional Models

Yan, Enxu 01 May 2018 (has links)
Across domains, the scale of data and complexity of models have both been increasing greatly in the recent years. For many models of interest, tractable learning and inference without access to expensive computational resources have become challenging. In this thesis, we approach efficient learning and inference through the leverage of sparse structures inherent in the learning objective, which allows us to develop algorithms sublinear in the size of parameters without compromising the accuracy of models. In particular, we address the following three questions for each problem of interest: (a) how to formulate model estimation as an optimization problem with tractable sparse structure, (b) how to efficiently, i.e. in sublinear time, search, maintain, and utilize the sparse structures during training and inference, (c) how to guarantee fast convergence of our optimization algorithm despite its greedy nature? By answering these questions, we develop state-of-the-art algorithms in varied domains. Specifically, in the extreme classification domain, we utilizes primal and dual sparse structures to develop greedy algorithms of complexity sublinear in the number of classes, which obtain state-of-the-art accuracies on several benchmark data sets with one or two orders of magnitude speedup over existing algorithms. We also apply the primal-dual-sparse theory to develop a state-of-the-art trimming algorithm for Deep Neural Networks, which sparsifies neuron connections of a DNN with a task-dependent theoretical guarantee, which results in models of smaller storage cost and faster inference speed. When it comes to structured prediction problems (i.e. graphical models) with inter-dependent outputs, we propose decomposition methods that exploit sparse messages to decompose a structured learning problem of large output domains into factorwise learning modules amenable to sublineartime optimization methods, leading to practically much faster alternatives to existing learning algorithms. The decomposition technique is especially effective when combined with search data structures, such as those for Maximum Inner-Product Search (MIPS), to improve the learning efficiency jointly. Last but not the least, we design novel convex estimators for a latent-variable model by reparameterizing it as a solution of sparse support in an exponentially high-dimensional space, and approximate it with a greedy algorithm, which yields the first polynomial-time approximation method for the Latent-Feature Models and Generalized Mixed Regression without restrictive data assumptions.
25

Provably efficient algorithms for decentralized optimization

Liu, Changxin 31 August 2021 (has links)
Decentralized multi-agent optimization has emerged as a powerful paradigm that finds broad applications in engineering design including federated machine learning and control of networked systems. In these setups, a group of agents are connected via a network with general topology. Under the communication constraint, they aim to solving a global optimization problem that is characterized collectively by their individual interests. Of particular importance are the computation and communication efficiency of decentralized optimization algorithms. Due to the heterogeneity of local objective functions, fostering cooperation across the agents over a possibly time-varying network is challenging yet necessary to achieve fast convergence to the global optimum. Furthermore, real-world communication networks are subject to congestion and bandwidth limit. To relieve the difficulty, it is highly desirable to design communication-efficient algorithms that proactively reduce the utilization of network resources. This dissertation tackles four concrete settings in decentralized optimization, and develops four provably efficient algorithms for solving them, respectively. Chapter 1 presents an overview of decentralized optimization, where some preliminaries, problem settings, and the state-of-the-art algorithms are introduced. Chapter 2 introduces the notation and reviews some key concepts that are useful throughout this dissertation. In Chapter 3, we investigate the non-smooth cost-coupled decentralized optimization and a special instance, that is, the dual form of constraint-coupled decentralized optimization. We develop a decentralized subgradient method with double averaging that guarantees the last iterate convergence, which is crucial to solving decentralized dual Lagrangian problems with convergence rate guarantee. Chapter 4 studies the composite cost-coupled decentralized optimization in stochastic networks, for which existing algorithms do not guarantee linear convergence. We propose a new decentralized dual averaging (DDA) algorithm to solve this problem. Under a rather mild condition on stochastic networks, we show that the proposed DDA attains an $\mathcal{O}(1/t)$ rate of convergence in the general case and a global linear rate of convergence if each local objective function is strongly convex. Chapter 5 tackles the smooth cost-coupled decentralized constrained optimization problem. We leverage the extrapolation technique and the average consensus protocol to develop an accelerated DDA algorithm. The rate of convergence is proved to be $\mathcal{O}\left( \frac{1}{t^2}+ \frac{1}{t(1-\beta)^2} \right)$, where $\beta$ denotes the second largest singular value of the mixing matrix. To proactively reduce the utilization of network resources, a communication-efficient decentralized primal-dual algorithm is developed based on the event-triggered broadcasting strategy in Chapter 6. In this algorithm, each agent locally determines whether to generate network transmissions by comparing a pre-defined threshold with the deviation between the iterates at present and lastly broadcast. Provided that the threshold sequence is summable over time, we prove an $\mathcal{O}(1/t)$ rate of convergence for convex composite objectives. For strongly convex and smooth problems, linear convergence is guaranteed if the threshold sequence is diminishing geometrically. Finally, Chapter 7 provides some concluding remarks and research directions for future study. / Graduate
26

Evaluating Neonatal Facial Pain Expression: Is There A Primal Face Of Pain?

Schiavenato, Martin 01 January 2007 (has links)
Pain assessment continues to be poorly managed in the clinical arena. A review of the communication process in pain assessment is carried out and the hierarchical approach often recommended in the literature -with self-report as its "gold-standard," is criticized as limited and simplistic. A comprehensive approach to pain assessment is recommended and a model that conceptualizes pain assessment as a complex transaction with various patient and clinician dependant factors is proposed. Attention is then focused on the pediatric patient whose pain assessment is often dependent on nonverbal communicative action. The clinical approaches to pain assessment in this population -mainly the use of behavioral/observational pain scales and facial pain scales, are explored. The primal face of pain (PFP) is identified and proposed theoretically as an important link in the function of facial pain scales. Finally, the existence of the PFP is investigated in a sample of 57 neonates across differences in sex and ethnic origin while controlling for potentially confounding factors. Facial expression to a painful stimulus is measured based on the Neonatal Facial Coding System (NFCS) and applying an innovative computer-based methodology. No statistically significant differences in facial expression were found in infant display thereby supporting the existence of the PFP.
27

A Case Study of a Male School Principal's Leadership Practices: An Exploration of Emotion & The Ethic of Care

Myers, Edward Leroy January 2013 (has links)
This qualitative single-site case study examined the philosophy, decisions, and behaviors of a particular male school principal who subscribed to a form of care-based leadership practice. A Pennsylvania high school principal with a distinct leadership philosophy centered on the ethic of care was chosen to participate in this study. The purpose of this study was to explore the role of emotion as it relates to leadership philosophy and the enactment of leadership decisions and actions. Additionally, the short and long-term organizational effects of leader behavior were examined. Semi-structured interviews with the principal, administrators, teachers, staff, parents, community members, and graduated students were utilized to examine how the principal's leadership philosophy was perceived and carried forth in school operations. Additionally, on-site observations and document reviews were utilized to aid the data collection process. The observation and analysis of the male school principal's leadership behavior was filtered through the lens of Goleman's, Boyatzis', and McKee's (2002) primal leadership theory and also through Gross' (1998, 2004, 2006) turbulence theory. Additionally, Wilson's (1998) theoretical conception of consilience was utilized as the physiological, psychological, ethical, social, emotional, and spiritual aspects of leadership were considered. These theoretical perspectives allowed for the review of principal leadership behavior in the context of unstable organizational conditions and accounted for the various elements involved with the leadership process. In turn, the male school principal's ability to implement his leadership philosophy was explored. This examination aimed to increase understanding of the intentions, actions, perceptions, and outcomes that arise from male school principal conduct that proposes to be aligned with a care-based leadership philosophy. The findings indicated the male school principal was able to successfully implement a care-based form of leadership practice. The results suggest that a particular leadership acuity, involving various rational, emotional, social, and moral competencies, was necessary for the school principal to experience success. Principal aptitude in these domains allowed the school leader to successfully lead his school organization during both stable and highly turbulent conditions. The findings suggest that the ethic of care, specifically in relation to Sernak's (1998) conception of caring power, should serve as the foundation for school organization leadership practice. Also, the findings offer various care-based school leadership aptitudes and behaviors that may be beneficial for school leadership theorists and practitioners to explore and consider. / Educational Administration
28

Une méthode de dualité pour des problèmes non convexes du Calcul des Variations / A duality method for non-convex problems in Calculus of Variations

Phan, Tran Duc Minh 28 June 2018 (has links)
Dans cette thèse, nous étudions un principe général de convexification permettant de traiter certainsproblèmes variationnels non convexes sur Rd. Grâce à ce principe nous pouvons mettre en oeuvre lespuissantes techniques de dualité et ramener de tels problèmes à des formulations de type primal–dualdans Rd+1, rendant ainsi efficace la recherche numérique de minima globaux. Une théorie de ladualité et des champs de calibration est reformulée dans le cas de fonctionnelles à croissance linéaire.Sous certaines hypothèses, cela nous permet de généraliser un principe d’exclusion découvert parVisintin dans les années 1990 et de réduire le problème initial à la minimisation d’une fonctionnelleconvexe sur Rd. Ce résultat s’applique notamment à une classe de problèmes à frontière libre oumulti-phasique donnant lieu à des tests numériques très convaincants au vu de la qualité des interfacesobtenues. Ensuite nous appliquons la théorie des calibrations à un problème classique de surfacesminimales avec frontière libre et établissons de nouveaux résultats de comparaison avec sa varianteoù la fonctionnelle des surfaces minimales est remplacée par la variation totale. Nous généralisonsla notion de calibrabilité introduite par Caselles-Chambolle et Al. et construisons explicitementune solution duale pour le problème associé à la seconde fonctionnelle en utilisant un potentiellocalement Lipschitzien lié à la distance au cut-locus. La dernière partie de la thèse est consacrée auxalgorithmes d’optimisation de type primal-dual pour la recherche de points selle, en introduisant denouvelles variantes plus efficaces en précision et temps calcul. Nous avons en particulier introduit unevariante semi-implicite de la méthode d’Arrow-Hurwicz qui permet de réduire le nombre d’itérationsnécessaires pour obtenir une qualité satisfaisante des interfaces. Enfin nous avons traité la nondifférentiabilité structurelle des Lagrangiens utilisés à l’aide d’une méthode géométrique de projectionsur l’épigraphe offrant ainsi une alternative aux méthodes classiques de régularisation. / In this thesis, we study a general principle of convexification to treat certain non convex variationalproblems in Rd. Thanks to this principle we are able to enforce the powerful duality techniques andbring back such problems to primal-dual formulations in Rd+1, thus making efficient the numericalsearch of a global minimizer. A theory of duality and calibration fields is reformulated in the caseof linear-growth functionals. Under suitable assumptions, this allows us to revisit and extend anexclusion principle discovered by Visintin in the 1990s and to reduce the original problem to theminimization of a convex functional in Rd. This result is then applied successfully to a class offree boundary or multiphase problems that we treat numerically obtaining very accurate interfaces.On the other hand we apply the theory of calibrations to a classical problem of minimal surfaceswith free boundary and establish new results related to the comparison with its variant where theminimal surfaces functional is replaced by the total variation. We generalize the notion of calibrabilityintroduced by Caselles-Chambolle and Al. and construct explicitly a dual solution for the problemassociated with the second functional by using a locally Lipschitzian potential related to the distanceto the cut-locus. The last part of the thesis is devoted to primal-dual optimization algorithms forthe search of saddle points, introducing new more efficient variants in precision and computationtime. In particular, we experiment a semi-implicit variant of the Arrow-Hurwicz method whichallows to reduce drastically the number of iterations necessary to obtain a sharp accuracy of theinterfaces. Eventually we tackle the structural non-differentiability of the Lagrangian arising fromour method by means of a geometric projection method on the epigraph, thus offering an alternativeto all classical regularization methods.
29

Estudo de técnicas eficientes para a resolução do problema de fluxo de potência para sistemas de distribuição radial / Study of efficient techniques for the resolution of power flow problem for distribution radial systems

Carvalho, Marcus Rodrigo 02 June 2006 (has links)
Este trabalho descreve uma abordagem do método primal-dual barreira logarítmica (MPDBL) associado ao método de Newton modificado para a resolução do problema de fluxo de potência para sistemas de distribuição radial. Também foi realizado um estudo comparativo com duas técnicas clássicas de solução do problema de fluxo potência para redes de distribuição radial. São os métodos: Backward/Forward Sweep e o método proposto por M. Baran e F. Wu, que é baseado na técnica de Newton-Raphson. Este método utiliza uma matriz Jacobiana modificada que atende a característica radial dos sistemas de distribuição. Nos testes comparativos serão considerados todos os parâmetros do sistema. Os algoritmos de solução serão analisados em suas propriedades de convergência e será realizado um teste de robustez. Os resultados dos testes realizados em 4 sistemas (4, 10, 34 e 70 barras) e o teste comparativo entre os métodos evidenciam a melhor metodologia na solução do problema de fluxo de potência para sistemas radiais / This work describes an approach on primal-dual logarithmic barrier method (PDLBM) associate to the method of Newton modified for the resolution of the problem of power flow for radial distribution systems. Also a comparative study with two classic techniques of solution of the flow problem was carried through power for nets of radial distribution. They are the methods: Backward/Forward Sweep and the method considered for M. Baran and F. Wu, that is based on the technique of Newton-Raphson. This method uses modified Jacobiana matrix that takes care of the radial characteristic of the distribution systems. In the comparative tests all will be considered the parameters of the system. The solution algorithms will be analyzed in its properties of convergence and will be carried through a robustness test. The results of the tests carried through in 4 systems (4, 10, 34 and 70 bus) and the comparative test between the methods evidence the best methodology in the solution of the problem of power flow for radial systems
30

Alocação de unidades de geração termoelétrica em sistemas elétricos de potência / Thermoelectrical generation allocation in electric power systems

Canola, Saulo Ricardo 16 January 2006 (has links)
Este trabalho tem como objetivo realizar um estudo de alocação de unidades termoelétricas em sistemas elétricos de potência (SEP). O fluxo de potencia ótimo (FPO) foi utilizado para se obter o ponto ótimo de operação para o sistema e os multiplicadores de Lagrange associados às restrições. Os multiplicadores de Lagrange indicam a sensibilidade entre a função objetivo e a restrição a ele associada. Esta sensibilidade indica, quais as barras do sistema, são candidatas à alocação de novas usinas termoelétricas. Testes nos sistemas de 5 barras, IEEE 14 barras, IEEE 30 barras, equivalente CESP 440 kV de 53 barras e IEEE 118 barras comprovam a eficiência da abordagem, a qual poderá ser utilizada em estudos de planejamento da expansão do sistema. / The aim of this paper is to present a study of thermoelectrical generation allocation in electric power systems. The optimal power flow (OPF) was used to evaluate the optimal operation point for the power system and also Lagrange multipliers associated with the constraints. The Lagrange multipliers are the sensitivity between the objective function and its constraints. This sensitivity is used to verify in a power system where is the best place to incentive the allocation of new thermoelectrical power plants. Tests on the systems: 5 buses, IEEE 14 buses, IEEE 30 buses, equivalent CESP 440kV 53 buses and IEEE 118 buses showed the efficiency of the presented approach. This method of analyzing the system can be used in study of expansion planning system.

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