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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.
451

En kartläggning av kompetenskraven på Sport managers

Thor, Jessica January 2008 (has links)
<p>The purpose of this study is to survey which competences and personal qualities the labour market, for students with examination from the Coaching and Sport management education at Vaxjo University, require. Furthermore I want to find out if the employees, videlicet the ex students, consider that their competences differentiate in relation to other employees in the organization which not have this education.</p><p>In the study a qualitative investigation method has been used where ten interviews have been implemented. The interviews have been carried out within five conceivable work areas to a student with examination from the Coaching and Sport management education at Vaxjo University. The work areas are sports association, sports union, municipal activity with sport and leisure time connection, company with health care connection and company without any kind of sport connection. Five of the persons being interviewed are ex students that now are employees within any of the elected work areas. The remaining five interviews have been carried out with the employer of respective employees.</p><p>The result of the study shows that the work which the employees perform within respective work area are relatively different but are despite everything of similar characteristic and can be deduced to the work that is included in the profession of a Sport manager. Between the work areas that have any kind of sport or health care connection their is an obvious connection between which qualifications that is demanded to recruitment and which competences and personal qualities that are important within each profession to perform its work. An obvious connection is also made clear among the competence weaknesses that the employees have, despite different work.</p><p>In the analysis the result is compared with the chosen theories to support the interpretations that are made. There are also suggestions given about changes that can be valuable to take into consideration in future planning of the course contents within the education of Coaching and Sport management at Vaxjo University.</p> / <p>Syftet med denna studie är att kartlägga vilka kompetenser och personliga egenskaper arbetsmarknaden, för studenter som gått Coaching och sportmanagement vid Växjö universitet, efterfrågar. Dessutom vill jag ta reda på om de anställda, det vill säga de före detta studenterna, anser att deras kompetenser skiljer sig i förhållande till andra medarbetare i organisationen som inte har denna utbildning.</p><p>I studien har en kvalitativ undersökningsmetod använts där tio intervjuer har genomförts. Intervjuerna har genomförts inom fem tänkbara arbetsområden för en student med examen från Coaching och Sportmanagementprogrammet vid Växjö universitet. Arbetsområdena är idrottsförening, idrottsförbund, kommunal verksamhet med idrotts och fritidsanknytning, företag med friskvårdsanknytning samt företag helt utan idrottsanknytning. Fem av intervjupersonerna är före detta studenter som numera är anställda inom något av de valda arbetsområdena, de övriga fem intervjuerna har genomförts med de anställda respektive arbetsgivare.</p><p>Resulatet av undersökningen visar att de arbetsuppgifter som de anställda utför inom respektive område är relativt olika men än dock av liknande karaktär och kan härledas till de arbetsuppgifter som ingår i yrket för en Sport manager. Mellan de arbetsområden som har någon form av idrotts- eller friskvårdsanknytning syns ett tydligt samband mellan vilka kvalifikationer som krävs vid rekrytering och vilka kompetenser och personliga egenskaper som är viktiga inom respektive yrke för att genomföra dess arbetsuppgifter. Ett tydligt samband går även att utläsa bland de kompetenssvagheter som de anställda besitter, trots olika arbetsuppgifter.</p><p>I analysen ställs resultatet mot de valda teorierna för att stärka de tolkningar som görs. Där ges även förslag på förändringar som kan vara värdefulla att ta i beaktande i framtida planering av kursinnehållet inom programmet för Coaching och Sport management vid Växjö universitet.</p>
452

Integrated network-based models for evaluating and optimizing the impact of electric vehicles on the transportation system

Zhang, Ti 13 November 2012 (has links)
The adoption of plug-in electric vehicles (PEV) requires research for models and algorithms tracing the vehicle assignment incorporating PEVs in the transportation network so that the traffic pattern can be more precisely and accurately predicted. To attain this goal, this dissertation is concerned with developing new formulations for modeling travelling behavior of electric vehicle drivers in a mixed flow traffic network environment. Much of the work in this dissertation is motivated by the special features of PEVs (such as range limitation, requirement of long electricity-recharging time, etc.), and the lack of tools of understanding PEV drivers traveling behavior and learning the impacts of charging infrastructure supply and policy on the network traffic pattern. The essential issues addressed in this dissertation are: (1) modeling the spatial choice behavior of electric vehicle drivers and analyzing the impacts from electricity-charging speed and price; (2) modeling the temporal and spatial choices behavior of electric vehicle drivers and analyzing the impacts of electric vehicle range and penetration rate; (3) and designing the optimal charging infrastructure investments and policy in the perspective of revenue management. Stochastic traffic assignment that can take into account for charging cost and charging time is first examined. Further, a quasi-dynamic stochastic user equilibrium model for combined choices of departure time, duration of stay and route, which integrates the nested-Logit discrete choice model, is formulated as a variational inequality problem. An extension from this equilibrium model is the network design model to determine an optimal charging infrastructure capacity and pricing. The objective is to maximize revenue subject to equilibrium constraints that explicitly consider the electric vehicle drivers’ combined choices behavior. The proposed models and algorithms are tested on small to middle size transportation networks. Extensive numerical experiments are conducted to assess the performance of the models. The research results contain the author’s initiative insights of network equilibrium models accounting for PEVs impacted by different scenarios of charging infrastructure supply, electric vehicles characteristics and penetration rates. The analytical tools developed in this dissertation, and the resulting insights obtained should offer an important first step to areas of travel demand modeling and policy making incorporating PEVs. / text
453

Approaches for traffic classification and the optimisation of radio resources in cellular networks : application to South Africa

Kurien, Anish Mathew. January 2012 (has links)
D. Tech. Electrical Engineering. / Objectives of the study is to propose a suitable feature extraction and classication approach that is capable of adapting to the non-linear nature and the noise contained in the time series data. The end goal of subscriber classication in this study is to utilise the subscriber information extracted for a new radio resource optimisation model that focuses on the Channel Allocation Problem CAP. Although there they have been various models proposed in literature for solving of the CAP problem, the utilisation of subscriber related information in the CAP has not been directly considered.
454

Understanding Generalization, Credit Assignment and the Regulation of Learning Rate in Human Motor Learning

Gonzalez Castro, Luis Nicolas January 2011 (has links)
Understanding the neural processes underlying motor learning in humans is important to facilitate the acquisition of new motor skills and to aid the relearning of skills lost after neurologic injury. Although it is known that the learning of a new movement is guided by the error feedback received after each repeated attempt to produce the movement, how the central nervous system (CNS) processes individual errors and how it modulates its learning rate in response to the history of errors experienced are issues that remain to be elucidated. To address these issues we studied the generalization of learning and learning decay – the transfer of what has been learned, or unlearned, in a particular movement condition to new movement conditions. Generalization offers a window into the process of error credit assignment during motor learning, since it allows us to measure which actions benefit the most in terms of learning after experiencing an error. We found that the distributions that describe generalization after learning are unimodal and biased towards the motion directions experienced during training, a finding that suggests that the credit for the learning experienced after a particular trial is assigned to the actual motion (motion-referenced learning) and not to the planned motion (plan-referenced learning) as it had previously been assumed in the motor learning literature. In addition, after training the same action along multiple directions, we found that the pattern of learning decay has two distinct components: one that is time-dependent and affects all trained directions, and one that is trial-dependent and affects mostly the direction where decay was induced, generalizing narrowly with a unimodal pattern similar to the one observed for learning generalization. We finally studied the effect that the consistency of the error perturbations in the training environment has on the learning rate adopted by the CNS. We found that learning rate increases when the perturbations experienced in training are consistent, and decreases when these perturbations are inconsistent. Besides increasing our understanding of the mechanisms underlying motor learning, the findings described in the present dissertation will enable the principled design of skill training and rehabilitation protocols that accelerate learning. / Engineering and Applied Sciences
455

Υλοποίηση και εξομοίωση ενός max-min fair sharing αλγορίθμου και σύγκριση αλγορίθμων χρονοπρογραμματισμού σε Grids / Implementation and simulation of fair grid scheduling algorithms

Νταφούλη, Ελένη 26 February 2009 (has links)
Θέμα της παρούσας εργασίας είναι η υλοποίηση και εξομοίωση δίκαιων αλγόριθμων χρονοπρογραμματισμού σε Grids και η σύγκρισή τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. Η βασική ιδέα πίσω από την τεχνολογία Grid και τις υπηρεσίες που παρέχει είναι η ενοποίηση υπολογιστικών και αποθηκευτικών πόρων και η συνολική θεώρηση τους από τους χρήστες. Με τον τρόπο αυτό γίνεται δυνατή η ανάπτυξη πολύπλοκων και απαιτητικών εφαρμογών, τόσο στον χώρο της επιστημονικής έρευνας, όσο και στα πλαίσια της παραγωγής εμπορικών λύσεων. Ένα τέτοιο σύστημα απαιτεί διαμοιρασμό των υπολογιστικών και άλλων πόρων καθώς και μεγάλες ταχύτητες σύνδεσης μεταξύ τους. Οι αλγόριθμοι χρονοπρογραμματισμού αναλαμβάνουν τον αποδοτικό διαμοιρασμό των πόρων ώστε να επιτυγχάνεται καλύτερη ποιότητα υπηρεσίας. Η αποτελεσματικότητα ενός αλγόριθμου χρονοπρογραμματισμού εξαρτάται από την συνάρτηση που θέλουμε να βελτιστοποιήσουμε, που με τη σειρά της εξαρτάται από τεχνο-οικονομικά κριτήρια. Στην προσπάθεια βελτιστοποίησης της εκάστοτε συνάρτησης ευνοούνται κάποιες προς εκτέλεση διεργασίες έναντι άλλων. Ένας δίκαιος αλγόριθμος χρονοπρογραμματισμού όμως θα πρέπει να συμπεριφέρεται με τον ίδιο τρόπο σε όλες τις διεργασίες ανεξαρτήτως των χαρακτηριστικών τους. Στην εργασία που θα παρουσιάσουμε, αναλύουμε δύο δίκαιους αλγόριθμους χρονοπρογραμματισμού, τον Fair Completion Time (Ordering) και τον Fair Completion Time Estimation (Assignment). Κατόπιν τους υλοποιούμε και τους εξομοιώνουμε με το GridSim Toolkit και συγκρίνουμε την απόδοση τους με κλασικούς αλγόριθμους χρονοπρογραμματισμού. / The subject of this thesis is the implementation and simulation of fair scheduling algorithms applied on Computational Grids and their comparison with the classic scheduling algorithms. The basic idea of the Grid Technology and the services it provides, is the unification of computational and storage resources. This way it is possible to serve sophisticated applications, in fields like scientific research and trading. A Grid Network demands the sharing of the computational and storage resources, and high bandwidth connections between them. Scheduling algorithms are responsible for the efficient assignment of tasks to resources for better quality of service. Evaluating the efficiency of a scheduling algorithm depends on a utility function that we seek to optimize which in turns depends on techno-economic criteria. As a result of trying to optimize the utility function, some tasks with specific characteristics are favoured against others. A fair scheduling algorithm however should treat all tasks in the same way regardless of their characteristics. In this thesis we study the Fair Completion Time Ordering Algorithm and suggest a new fair scheduling algorithm called Fair Completion Time Estimation Assignment Algorithm. We implement and simulate these algorithms using the GridSim Toolkit and compare them with the classic scheduling algorithms.
456

Δρομολόγηση και ανάθεση μήκους κύματος σε οπτικά δίκτυα βασισμένη στα φυσικά χαρακτηριστικά του δικτύου

Μανουσάκης, Κωνσταντίνος 26 October 2007 (has links)
Ο πιο σύγχρονος και περισσότερα υποσχόμενος τύπος οπτικών δικτύων, είναι τα οπτικά δίκτυα πολυπλεξίας διαίρεσης μήκους κύματος (Wavelength Division Multiplexing – WDM). Τα δίκτυα αυτά διαθέτουν τεράστια χωρητικότητα και αναμένεται να αποτελέσουν τα μελλοντικά δίκτυα κορμού για τη μεταφορά μεγάλου όγκου δεδομένων. Η πλήρης αξιοποίηση της χωρητικότητας των WDM δικτύων, όμως, απαιτεί την επίλυση ειδικών θεμάτων που σχετίζονται µε τις ιδιαιτερότητες και τη φύση των WDM οπτικών δικτύων. Το σημαντικότερο ίσως από αυτά είναι το πρόβλημα της δρομολόγησης και ανάθεσης μήκους κύματος (Routing and Wavelength Assignment – RWA), πάνω στο οποίο έχει αναπτυχθεί έντονη ερευνητική δραστηριότητα τα τελευταία χρόνια, το οποίο είναι NP-πλήρες. Ένα άλλο θέμα που χρήζει ιδιαίτερης προσοχής είναι οι εξασθενήσεις που υφίσταται ένα σήμα μέσα στο οπτικό δίκτυο. Όταν λοιπόν κάποιο σήμα διαδίδεται κατά μήκος ενός οπτικού μονοπατιού πέφτει η ποιότητα του εξαιτίας των φυσικών επιδράσεων που δέχεται. Οι φυσικές επιδράσεις κατά κανόνα μειώνουν τον λόγο σήματος προς θόρυβο (SNR), με αποτέλεσμα να αυξηθεί σημαντικά και η συχνότητα εμφάνισης λαθών (BER) στον κόμβο προορισμού. Αν η παραπάνω συχνότητα εμφάνισης λαθών είναι μεγαλύτερη από ένα καθορισμένο όριο, τότε το αίτημα δρομολόγησης θα πρέπει να απορριφθεί. Επομένως κατά την επίλυση του RWA προβλήματος θα πρέπει να ληφθούν υπόψη οι επιδράσεις που προκαλούνται στο σήμα λόγω των φυσικών χαρακτηριστικών του δικτύου. Στην παρούσα διπλωματική εργασία έχει υλοποιηθεί ένας αλγόριθμος για την επίλυση του στατικού RWA, που βασίζεται στην μοντελοποίηση ενός γραμμικού προβλήματος (Linear Programming – LP). Κατά την μοντελοποίηση λαμβάνονται υπόψη οι πιο σημαντικές επιδράσεις, όπως η χρωματική διασπορά (Chromatic Dispersion – CD), η διασπορά τρόπου πόλωσης (Polarization Mode Dispersion – PMD), η ενισχυμένη αυθόρμητη εκπομπή (Amplifier Spontaneous Emission – ASE) και η αλληλεπίδραση γειτονικών καναλιών (crosstalk). Η επίδραση των τριών πρώτων παραμέτρων εξαρτάται αποκλειστικά από τα χαρακτηριστικά των συνδέσμων και μοντελοποιούνται σύμφωνα με αναλυτικούς τύπους, ενώ η επίδραση του crosstalk εξαρτάται από τον αριθμό των οπτικών μονοπατιών που διατρέχουν ένα σύνδεσμο. Προτείνεται επίσης μία συνάρτηση βελτιστοποίησης ώστε να προκύπτουν ακέραιες λύσεις με πολύ μεγάλη πιθανότητα από την επίλυση του LP (Linear Program) προβλήματος. Αυτός ο αλγόριθμος εφαρμόζεται σε ένα μητροπολιτικό δίκτυο και λαμβάνονται συγκριτικά αποτελέσματα για διάφορες παραμέτρους των φυσικών στοιχείων του δικτύου. / Wavelength division multiplexing (WDM) is a promising technology for faster and more reliable data communication networks. In a WDM network several optical signals are sent on the same fiber using different wavelength channels. Multiple WDM channels from different end users may be multiplexed on the same fiber. Traditionally only a small fraction of the fiber capacity is in use, but by using WDM it is possible to exploit this huge capacity more efficiently. Under WDM, the optical transmission spectrum is curved up into a number of non-overlapping wavelength bands, with each wavelength supporting a single communication channel operating at whatever rate one desires. WDM technology has been recognized as one of the key components of the future networks. Routing and wavelength assignment (RWA) is a crucial issue for WDM optical network designers. In wavelength routed WDM optical networks connections between terminal stations are established through the use of lightpaths. Given a WDM optical topology and a set of connection requests between pairs of source-destination terminal nodes, the problem of how to route all the lightpaths simultaneously, one per connection, and which wavelength should be assigned to each one of them, subject to minimizing network resources or maximizing traffic characteristics, arises; this is known as the Routing and Wavelength Assignment problem RWA. In transparent networks, the signal quality is subject to a variety of physical impairments, such as polarization mode dispersion (PMD), amplified spontaneous emission (ASE) noise and chromatic dispersion (CD) and crosstalk. These impairments are linearly modeled and handled effectively by a set of analytical formulas as additional constraints on RWA. We apply our algorithm to perform impairment-constraint based RWA, in order to obtain comparative results of a typical metropolitan network's performance under various network and impairment parameters, such as bit rate, amplifier gain and type, modulation format used, etc.
457

Algorithms for irreducible infeasible subset detection in CSP - Application to frequency planning and graph k-coloring

Hu, Jun 27 November 2012 (has links) (PDF)
The frequency assignment (FAP) consists in assigning the frequency on the radio links of a network which satisfiesthe electromagnetic interference among the links. Given the limited spectrum resources for each application, the fre-quency resources are often insufficient to deploy a wireless network without interference. In this case, the network isover-contrained and the problem is infeasible. Our objective is to identify an area with heavy interference.The work presented here concerns the detection for one of these areas with an algorithmic approach based onmodeling the problem by CSP. The problem of frequency assignment can be modeled as a constraint satisfactionproblem (CSP) which is represented by a triple: a set of variables (radio links), a set of constraints (electromagneticinterference) and a set of available frequencies.The interfered area in CSP can be considered a subset of irreducible feasible subset (IIS). An IIS is a infeasiblesubproblem with irreducible size, that is to say that all subsets of an IIS are feasible. The identification of an IIS ina CSP refers to two general interests. First, locating an IIS can easily prove the infeasibility of the problem. Becausethe size of IIS is assumed to be smaller compared to the entire problem, its infeasibility is relatively easier to prove.Second, we can locate the reason of infeasibility, in this case, the decision maker can provide the solutions to relax theconstraints inside IIS, which perhaps leads to a feasible solution to the problem.This work proposes algorithms to identify an IIS in the over-constrained CSP. These algorithms have tested on the well known benchmarks of the FAP and of the problem of graph k-coloring. The results show a significant improve-ment on instances of FAP compared to known methods.
458

Reikalavimo perleidimas ir subrogacija: sampratos ir santykio problemos / Assignment of claim and subrogation: the problems of conception and relation

Neringa, Sarulytė 25 January 2008 (has links)
Magistro baigiamajame darbe yra nagrinėjami du asmenų pasikeitimo prievolėje būdai – reikalavimo perleidimas (cesija) ir subrogacija. Pateikiama reikalavimo perleidimo ir subrogacijos institutų istorinio atsiradimo Senovės Romoje apžvalga, analizuojamos reikalavimo perleidimo ir subrogacijos sąvokos bei šių institutų teisinė prigimtis Lietuvos bei užsienio civilinės teisės sistemose. Autorė detaliai nagrinėja reikalavimo perleidimo (cesijos) bei subrogacijos institutus, atskleidžia esmines šių institutų sampratos problemas bei prievolės šalių teisinės padėties reglamentavimo ypatumus. Darbe taip pat skiriama nemažai dėmesio santykio tarp reikalavimo perleidimo (cesijos) ir subrogacijos nustatymui. 2000 m. Lietuvos Respublikos civiliniame kodekse įtvirtintas subrogacijos teisinis reglamentavimas suponuoja išvadą, jog subrogacija yra atskira reikalavimo perleidimo rūšis. Darbe autorė suformuluoja kriterijus, kurie padeda atskirti reikalavimo perleidimo ir subrogacijos institutus ir laikyti juos dviem savarankiškais asmenų pasikeitimo prievolėje būdais. Atsižvelgiant į tai, kad subrogacija 2000 m. Lietuvos Respublikos civiliniame kodekse yra reglamentuota kaip ypatinga regreso teisės rūšis, tačiau tuo pačiu tai yra atskiras asmenų pasikeitimo prievolėje būdas, todėl autorė pateikia kriterijus, kurių pagrindu yra atskiriama subrogacija bei regreso teisė. Darbe taip pat pateikiami praktiniai autorės pasiūlymai, skirti galiojančių teisės aktų tobulinimui, atsižvelgiant į darbe... [toliau žr. visą tekstą] / Master‘s final thesis is devoted to the analysis of two different ways of change of persons in an obligation – assignment of claim (cession) and subrogation. The author puts through the review of the historical development of the institutes of cession and subrogation since the times of Roman law, analyses the conceptions of assignment of claim and subrogation and legal nature of these institutes in the legal system of Lithuania and other foreign countries. The author thoroughly researches the institutes of assignment of claim (cession) and subrogation, points out the main problems arising in the field of conception of these institutes and approaches to the pecularities of the legal position of persons in an obligation. This Thesis at large scale approaches to detection of the relation between assignment of claim (cession) and subrogation. The legal regulation of subrogation, provided in the Civil code of the Republic of Lithuania, supposes the conclusion that subrogation is a particular kind of assignment of claim. The Author formulates criteria which help to separate the institutes of assignment of claim and subrogation and allows to treat them as two separate ways of change of persons in an obligation. The legal regulation, provided in the Civil Code of the Republic of Lithuania, treats subrogation as a particular kind of the right of regress but subrogation at the same time is a seperate way of change of persons in an obligation and due to this situation the author... [to full text]
459

Les déterminants de l’acceptation d’une affectation à l’international

Pouliot, Benoit 09 1900 (has links)
Cette étude porte les raisons de l’acceptation d’une affectation internationale. Alors que l’augmentation du nombre d’entreprises et d’activités internationales crée une pression de plus en plus forte à recourir à la mobilité internationale, ces entreprises éprouvent toujours certaines difficultés à attirer et à sélectionner les bons candidats. Notre étude, effectuée auprès d’individus travaillant dans le domaine de l’ingénierie-construction, visait, dans un premier temps, à connaître quels sont les déterminants individuels, organisationnels et de l’affectation dans l’acceptation d’une affectation à l’international. Dans un second temps, nous avons cherché à vérifier l’importance relative de ces déterminants dans l’acceptation d’une affectation à l’international. Nos analyses ont révélé que deux déterminants individuels et sept déterminants organisationnels ont influence positive significative dans l’acceptation d’une affectation internationale. / This study’s main focus is the reasons that are involved in the acceptance of an international assignment. While the number of multinational corporations is increasing, so is the pressure to attract and select candidates that will accept an international assignment. Based on a sample of employees working in engineering and construction, our study had two main goals. First, we sought to identify which are the key individual, organisational and assignment variables in the decision to accept or refuse an international assignment. The second goal was to verify the relative importance of those key variables in the acceptation of an international assignment. Our analyses revealed that two individual variables and seven organisational variables have a significant and positive influence in the acceptance of an international assignment.
460

Dirbtinės bičių kolonijos algoritmai ir jų taikymai skirstymo uždaviniams spręsti / Artificial Bee Colony Algorithms and their Application to Assigment Problems

Matakas, Linas 29 July 2013 (has links)
Šiame darbe yra trumpai apžvelgiami dalelių spiečių sistemų algoritmai, skirstymo uždaviniai ir jų formuluotės, bei praktinės interpretacijos, plačiau apžvelgiami ir analizuojami dirbtinių bičių kolonijų algoritmai. Taip pat šiame darbe galima rasti dirbtinių bičių kolonijų algoritmo pritaikymą skirstymo uždaviniams spręsti, bei sukurtos programos skaičiavimo rezultatų analizę. / This paper consists of short descriptions of swarm systems algorithms, assigment problems and longer overview of artificial bee colony algorithms and it‘s analysis. Moreover, you can find an Artificial Bee Colony Algorithm's Application to one of an Assigment Problems and it's computational results analysis.

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