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Filter-Trust-Region Methods for Nonlinear OptimizationSainvitu, Caroline 17 April 2007 (has links)
This work is concerned with the theoretical study and the implementation of algorithms for solving two particular types of nonlinear optimization problems, namely unconstrained and simple-bound constrained optimization problems. For unconstrained optimization, we develop a new algorithm which uses a filter technique and a trust-region method in order to enforce global convergence and to improve the efficiency of traditional approaches. We also analyze the effect of approximate first and second derivatives on the performance of the filter-trust-region algorithm. We next extend our algorithm to simple-bound constrained optimization problems by combining these ideas with a gradient-projection method. Numerical results follow the proposed methods and indicate that they are competitive with more classical trust-region algorithms.
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Constrained an unconstrained optimisation with trust regions methods and quadratic local approximations/Optimisation contrainte et non-contrainte par régions de confiance avec approximations locales quadratiquesWalmag, Jérôme 21 March 2011 (has links)
This work deals with optimisation problems in which the numerical cost associated with the evaluation of the target function and/or of the constraints is large; the number of calls to these functions by the optimisation algorithm should therefore be kept as small as possible.
The first part of the work is about globalisation by trust regions where the objective function and the constraints are replaced by a local approximation, easier to use, in a certain region of confidence.
Different types of local approximations are introduced but the main part of the work deals with quadratic approximations. The theoretical aspects of the global convergence of trust regions methods are also presented.
One of the applications considered in this work is the parametrical identification of a dynamical model with respect to experimental measurements. This identification can be expressed in the form of an unconstrained optimisation problem. For the practical implementation of the identification algorithm, the derivative of the objective function is required, which asks for the derivation of the underlying model. An algorithm, named Trust, has been implemented: it is a trust region method of quasi-Newton type which uses quadratic local approximations. The choice of the differentiation method is analysed in details in relation with its influence on the rate of convergence.
A brand new update strategy of the trust region radius is also introduced. The trust region radius is a parameter that measures the size of the trust region around the current iterate. The new approach relies on the identification and appropriate handling of so-called too successful iterations that lead to a much more important reduction of the function objective than predicted by the local approximation. This approach goes with a significant improvement of the performances of the algorithm.
Constrained optimisation is then considered using sequential quadratic methods. A fully effective algorithm for the resolution of quadratic convex sub-problems with quadratic constraints is introduced. This original method, named UVQCQP, makes use of an exact non-differentiable penalty function to addresses the constrained optimisation problem. The algorithm relies on a decomposition of the variable space into three orthogonal subspaces: a first subspace taking into account bound constraints, a second one in which the objective function is continuously derivable and a third one with slope discontinuities. The performances of this algorithm are further improved by the implementation of a fast mode taking into account the second order corrections.
Eventually, the UVQCQP algorithm is applied within the framework of sequential algorithms of quadratic programming with quadratic constraints: its advantages are demonstrated through some examples. The numerical tests carried out reveal very encouraging prospects.
/Ce travail s'intéresse aux problèmes doptimisation dans lesquels le temps de calcul de la fonction cible et/ou des contraintes est très important et où le nombre dappels à ces fonctions par l'algorithme doptimisation doit donc être aussi réduit que possible.
La première partie du travail porte sur la technique de globalisation dite par régions de confiance où la fonction objectif et les contraintes peuvent être remplacées par une approximation locale, plus facile à utiliser, dans une certaine zone de confiance.
Plusieurs types d'approximations locales sont développées en détail mais l'essentiel du travail se concentre sur les approximations quadratiques. Les aspects théoriques de convergence globale des méthodes par régions de confiance sont également présentés.
Une des applications envisagées porte sur l'identification paramétrique d'un modèle dynamique par rapport à des mesures expérimentales. Cette identification peut être exprimée sous la forme d'un problème d'optimisation non-contraint. Pour être menée à bien, lidentification nécessite la différentiation de la fonction objectif et donc du modèle sous-jacent : le facteur-clé est son coût en ressources informatiques et cette question est passée en revue en détail. Un algorithme, nommé Trust, a été implémenté : cest une méthode par régions de confiance de type quasi-Newton qui utilise des approximations locales quadratiques. Le choix de la méthode de différentiation est analysé car celui-ci influence la vitesse de convergence.
Ce travail introduit également une stratégie nouvelle de mise à jour du rayon de confiance. Le rayon de confiance est un paramètre des méthodes par régions de confiance qui mesure l'étendue de la dite région autour de l'itéré courant. La nouveauté développée ici invite à se méfier des itérations menant à une réduction de la fonction objectif bien plus importante que celle prévue par l'approximation locale. Cette approche permet une amélioration sensible des performances de l'algorithme.
Le travail aborde ensuite la question de l'optimisation contrainte en se basant sur les méthodes quadratiques séquentielles. Il présente un algorithme complet et efficace de résolution d'un sous-problème convexe quadratique à contraintes quadratiques. Cette méthode originale, nommée UVQCQP, se base sur une fonction de pénalité exacte non-différentiable. L'algorithme tire profit d'une décomposition de l'espace des variables en trois sous-espaces orthogonaux : un premier permettant de gérer des contraintes de bornes, un deuxième dans lequel la fonction objectif est continûment dérivable et un troisième où elle présente des cassures de pente. Les performances de cet algorithme sont encore améliorées par l'implémentation d'un mode rapide qui tire profit de corrections du second ordre.
Pour terminer, lalgorithme UVQCQP est appliqué dans le cadre dalgorithmes séquentiels de programmation quadratique à contraintes quadratiques : ses avantages sont abordés au travers de quelques exemples. Les tests numériques effectués font apparaître des perspectives très encourageantes.
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Trusten - skattesubjekt i Sverige? : The Trust - recognizable for Tax Purposes?Wadström, Paula January 2005 (has links)
I uppsatsen utreds om det utländska institutet trust kan vara ett skattesubjekt inom den svenska skatterätten. I sitt eget hemland är truster ofta inte att betrakta som ett eget skattesubjekt utan där behandlas trusters förvaltare som dess ägare och därmed även som skattesubjekt vid beskattning av trustinkomst, förmögenhet m.m. När truster figurerat i svenska rättsfall har ofta trusten, utan närmare motivering, liknats vid en stiftelse. Regeringsrätten har ansett en utländsk stiftelse vara en utländsk juridisk person och en i Sverige begränsat skattskyldig person. Kan även trusten vara ett skattesubjekt? Genom att undersöka det civilrättsliga stiftelsebegreppet har upptäckts att stiftelsebegreppet är långt ifrån enhetligt. Vid en genomgång av stiftelsebeskattningspraxis framkommer att stiftelsebeskattning har tillgripits även på förordnanden som inte är stiftelser i strikt mening och att hänsyn måste tas till hur en rättsfigur ser ut och inte hur den benämns. En diskussion förs även kring ur vilken rättsordnings perspektiv som trusten skall granskas. / This essay deals with the question whether a trust can be recognizable for tax purposes in Sweden. In its home state it is often the trustee, and not the trust itself, who is regarded as the owner of the fund and therefore also liable to income tax etc. Trusts have often, and without any explanation, been compared to a foundation when it has appeared in Swedish legal cases. The Swedish Supreme Administrative Court has considered a foreign foundation to be recognizable to tax in Sweden. Could that be indicating that also a trust could be recognizable? By examining the concept of foundation it is found that it is far from being uniform. Going through case law regarding foundations and tax one can see that in the assessing of taxes no strict line has been upheld for what is a foundation and what is not. One has to take more into consideration than just the name of a legal figure. The question from what legal system a foreign legal figure, such as the trust, is to be viewed is also brought up to discussion.
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Trust of Direct Leaders Influences Organizational Commitment and Job InvolvementLee, Min 17 August 2007 (has links)
This research was to learn the trust of direct leaders from the points of the
staff, and to discuss how to influence organizational commitment and job
involvement. Since trust of direct leaders was one of the key factors to increase
organizational commitment and job involvement, the cohesion will turn up when the
staff accept the concern from directors, and the group can collaborate. Therefore, the
operation of an organized system and the achievement of assignment were necessary
to base on the trust of direct leaders, then it brought the maximum beneficial result.
After getting nine hundred and thirty-six available questionnaires, this research used
the methods of Analysis of One-Way Factorial Variance, Correlation Analysis, and
Analytical Regression Process to get the verification. According to the statistics, I
addressed the conclusion and recommendation of this research.
In the discovery of the result, individual variables were including the trust of
direct leaders, organizational commitment and job involvement. There wasn¡¦t
any noticeable difference in sex, but it existed in marriage, age, work experience,
education level and position. Moreover, according to the result of the research in
Correlation Analysis, the trust of direct leaders, organizational commitment and job
involvement caused high positive correlation . It means the degree of the trust of
direct leaders is higher, and the staff would have higher organizational commitment,
and degree of job identification and involvement. In addition, the work experience
with directors was interference variables, and to prove if there was the interference
effect in the trust of direct leaders from organizational commitment and job
involvement, the verified result revealed that there wasn¡¦t any interference effect in
any other factors, except Cognition-based Trust could effect the value and effort
commitment . In terms of the collection of this research results, the assumptions
approximately existed in Correlation Analysis, and on the contrary, they didn¡¦t exist in
interference effect.
In conclusion, I had some recommendation for this research to provide the
enterprise some different ideas and directions of management. The organization
should emphasize how to increase the trust of direct leaders, enhance the interaction
between the management and the staff, lift organizational commitment from the
personnel, and raise the degree of job involvement for the advantage of the
organization development.
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INFLUENCE OF LANGUAGE ON KNOWLEDGE SHARING : A CASE STUDY OF PAKISTANI WORKERS IN SELECTED SWEDISH MULTINATIONAL COMPANIESAmin, Asad, Shahid, Muhammad Imran January 2013 (has links)
No description available.
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Comparative Analysis between the Canadian Trust and the Panamanian Foundation of Private InterestTedman, Frank 11 January 2011 (has links)
Canadian Trusts and Panamanian Foundations of Private Interest are generally utilized as juridical vehicles through which a creator can designate a person to hold and administer property for the benefit and enjoyment of a beneficiary. Given the similarity of application of both vehicles, and taking into consideration that they emanate from separate juridical and judicial systems, it is pertinent to analytically compare them.
As can be expected, there is a significant number of aspects through which Foundations of Private Interest and a Trusts can be compared. The following comparative analysis will be centered around three aspects: Asset ownership, creation mechanisms and the requirement of properly identifying beneficiaries. Preceding the aforementioned comparative analysis, a presentation and description of both legal vehicles will be provided in order to make the comparative analysis comprehensible and hopefully useful.
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Comparative Analysis between the Canadian Trust and the Panamanian Foundation of Private InterestTedman, Frank 11 January 2011 (has links)
Canadian Trusts and Panamanian Foundations of Private Interest are generally utilized as juridical vehicles through which a creator can designate a person to hold and administer property for the benefit and enjoyment of a beneficiary. Given the similarity of application of both vehicles, and taking into consideration that they emanate from separate juridical and judicial systems, it is pertinent to analytically compare them.
As can be expected, there is a significant number of aspects through which Foundations of Private Interest and a Trusts can be compared. The following comparative analysis will be centered around three aspects: Asset ownership, creation mechanisms and the requirement of properly identifying beneficiaries. Preceding the aforementioned comparative analysis, a presentation and description of both legal vehicles will be provided in order to make the comparative analysis comprehensible and hopefully useful.
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According to Swedish Citizens - Sweden has the Safest and Best Food in the World : -Really?Berggren, Benny, Nasser Fouda, Mai January 2013 (has links)
Title: According to Swedish Citizens – Sweden has the Safest and Best food in the world – Really? Level: Thesis for Master’s Degree in Business Administration Authors: Benny Berggren and Mai Nasser Fouda Supervisor: Jonas Kågström, Ph.D. Date: May 20, 2013 Aim: The aim of this thesis is to fill the research gap on whether there are differences in how Swedish consumers remember publicized scandals in regards to the Country of Origin (COO), focusing on age, gender and time. Furthermore, this paper will also aim to look at how different scandals have affected the consumers trust based on whether foreign food scandals have a higher impact. Methodology: Since this thesis tested different relationships a deductive approach was taken with a conclusive research design. Quantitative data was collected via a VAS-scale questionnaire to 187 individuals via random sampling at train stations which had a response rate of 75,9%. By using SPSS, the primary data was analyzed via a Correlation and Factor analysis in accordance with scientific articles from within the fields of Purchasing Decision theory, the COO and Consumer Memory. A semi-open telephone interview with an expert from within the food industry was conducted as additional explanations to the findings were needed. Result & Conclusions: It was found that Swedish consumers remembered scandals differently depending on origin, and were according to themselves more affected by the foreign scandals. Gender did not have a preference depending on the COO of the product and consumer memory while age did. It was also found that trusting food was the essential theme throughout the empirical findings where the Swedish consumers valued cues such as food quality and food safety. This played a significant role on impacting the consumer’s long-term memory. Three different types of trust was found and divided by their characteristics; High-level-involvement products, the COO of the product or the company which the scandal was involved with, and finally, the size, positioning and equity of the brand involved. Business implications: Media can be seen as a key source of spreading negative publicity regarding scandals. It is therefore extra important for companies to act immediately, especially if they have any of the three characteristics of trust since it influences the consumer’s long-term memory in a negative way. These three characteristics combined could have strong more negative impact on the companies, where there is a risk of losing potential & current business partners, decreased brand equity & image and risk of facing legal aspects. This can be very costly both financially and time-wise which ultimately could lead to a negative turnover. Research Implications: future research is suggested to study why the results in this thesis differ from the other scientific findings when it comes to gender. Also suggested is that studies should be conducted similar to this, but based on specific types of food products since this thesis only studied food in general. Furthermore, studies comparing the effect of the consumer memory in regards to food scandals based on different companies are also suggested. Key words: Country of Origin, Scandals, Memory, Trust, Purchasing behavior.
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Trust and reputation for agent societiesSabater Mir, Jordi 28 July 2002 (has links)
No description available.
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The role of Relationship Marketing for Customer satisfaction in the banking sectorMatagne, Sébastien, Gérard, Mark January 2013 (has links)
More and more companies are faced with fierce competition; ergo, companies are consistently trying to build a long term relationships with their customer. In addition, a decade ago, relationship marketing gained more and more credibility among the companies and is still a topic of discussion today. Therefore, this study is aimed to describe how service firms can use relationship marketing as a strategy to develop customer satisfaction. A theoretical framework has been developed derived from a review of the existing literature in order to describe how service firms can use relationship marketing as a strategy to develop customer satisfaction. Five different tactics have been empirically investigated, namely the service quality, brand image, price perception, value offers and communication. A qualitative method has been chosen for this study. Three different companies have been studied within the banking sector and have been led by an inductive and deductive approach which will aim to investigate the aforementioned theoretical framework. The analysis of the empirical findings exposed and discovered some relevant findings. Indeed, empirical evidence suggests that four main customer relationship tactics have a role on customer satisfaction and trust; namely the service quality, the brand image, the price perception and the human capital. These tactics have been identified as having a crucial role on gaining customer satisfaction.
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