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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.
81

Would you like your receipt? : Sustainability perspectives of consumer paper receipts

Sarenmalm, Isabel January 2016 (has links)
This report researches and analyses the sustainability perspectives of paper receipts, focusing on the economical, environmental and social aspects using a qualitative research method and by simultaneously drawing inspiration from the Sustainability Impact Assessment (SIA) model. The result section is conducted by using a literature review where a combination of previously used sources within my masters program is analysed and by reviewing articles and statistics in the search engine at the Uppsala University e-library database. The overall research purpose, to assess the sustainability of consumer receipts, is achieved by using the concept of sustainable development as the theoretical framework. This report suggests that there are some sustainability concerns with the current consumption of the traditional paper receipt, mainly in the context of environmental and social considerations. Three different alternatives to the traditional paper receipt are furthermore discussed as examples of potential routes forward. Two of the alternatives, electronic receipts and introducing a charge on paper receipts, are arguably the two most sustainable alternatives to regular paper receipts. The third alternative cannot be perceived as equally sustainable since “BPA/Bisphenol-free” receipts contain other chemicals equivalently hazardous to humans and the environment.
82

AUTOMATIC TOOLS FOR TELEMETRY TEST RANGE SPECTRUM MANAGEMENT

Woolsey, Roy B. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Automatic spectrum management and monitoring systems are very useful to manage frequencies at test ranges and assure interference-free transmission of telemetry signals. Spectrum management systems assign telemetry frequencies using database information on available and occupied channels and analysis tools which can determine whether a data link will support telemetry. Modern, DSP-based spectrum monitoring systems, in fixed or mobile configurations, automate the process of performing spectrum occupancy to verify clear channels and identify and locate sources of interference; they are integrated with and utilize the management system database. Such systems are important to assure reliable communications channels for telemetry.
83

DEVELOPMENT AND IMPLEMENTATION OF THE MULTI-RESOLUTION AND LOADING OF TRANSPORTATION ACTIVITIES (MALTA) SIMULATION BASED DYNAMIC TRAFFIC ASSIGNMENT SYSTEM, RECURSIVE ON-LINE LOAD BALANCE FRAMEWORK (ROLB)

Villalobos, Jorge Alejandro January 2011 (has links)
The Multi-resolution Assignment and Loading of Transport Activities (MALTA) system is a simulation-based Dynamic Traffic Assignment model that exploits the advantages of multi-processor computing via the use of the Message Passing Interface (MPI) protocol. Spatially partitioned transportation networks are utilized to estimate travel time via alternate routes on mega-scale network models, while the concurrently run shortest path and assignment procedures evaluate traffic conditions and re-assign traffic in order to achieve traffic assignment goals such as User Optimal and/or System Optimal conditions.Performance gain is obtained via the spatial partitioning architecture that allows the simulation domains to distribute the work load based on a specially designed Recursive On-line Load Balance model (ROLB). The ROLB development describes how the transportation network is transformed into an ordered node network which serves as the basis for a minimum cost heuristic, solved using the shortest path, which solves a multi-objective NP Hard binary optimization problem. The approach to this problem contains a least-squares formulation that attempts to balance the computational load of each of the mSim domains as well as to minimize the inter-domain communication requirements. The model is developed from its formal formulation to the heuristic utilized to quickly solve the problem. As a component of the balancing model, a load forecasting technique is used, Fast Sim, to determine what the link loading of the future network in order to estimate average future link speeds enabling a good solution for the ROLB method.The runtime performance of the MALTA model is described in detail. It is shown how a 94% reduction in runtime was achieved with the Maricopa Association of Governments (MAG) network with the use of 33 CPUs. The runtime was reduced from over 60 minutes of runtime on one machine to less than 5 minutes on the 33 CPUs. The results also showed how the individual runtimes on each of the simulation domains could vary drastically with naïve partitioning methods as opposed to the balanced run-time using the ROLB method; confirming the need to have a load balancing technique for MALTA.
84

Improving Order Picking Processes through Proper Storage Assignment : Using results from previous mathematical research to simplify solving real life problems

Patoka, Markus January 2016 (has links)
The area of order picking has been widely studied but still there is no general approach covering all the potential variables of a unique case. Optimizing the product placement is a useful way to improve order picking through reduced travel distances and goes hand in hand with an appropriate batching strategy and routing policy. The existing methods are of mathematical basis and can be costly to implement and it is therefore necessary to develop a non-mathematical approach that can be used for distribution centers and in this particular case, the warehouse of a mail order company. Literature is reviewed to investigate the current situation of a large Swedish mail order retailer for the development of a unique product assignment strategy, taking into consideration potential variables. It was found out that a lot of trade-offs are being done all the time between travel distances of the SKUs. Also, it was found out that “cart blocking” might be a potential problem when using a turnover-based storage assignment strategy.
85

Modeling the problem of assigning Virginia’s localities to DCR’s Regional Offices

Srinivasan, Sudharshana 15 July 2009 (has links)
Virginia’s Department of Conservation and Recreation (DCR) assigns all of Virginia localities to Regional Offices to help conserve the natural resources in a certain region. In this paper, we present a mathematical model for optimizing such assignments by minimizing the travel time and cost of these assignments. With the growing increase in fuel costs and tighter budgets, our solution finds alternate assignments that will help cut costs by 14% annually. We have used integer programming techniques to find optimal assignments which satisfy requirements, respect limitations and minimize cost. Several plans are suggested, some keeping soil and water conservation districts together and some without.
86

Postoupení smlouvy / Assignment od Contract

Zach, Tomáš January 2015 (has links)
Assignment of Contract The purpose of this master's thesis is to analyze the assignability of contracts under Czech law in the light of comparative, historical and theoretical aspects of this phenomenon. Relevance of this subject matter was recently highlighted by adoption of the new Czech Civil Code, which expressly authorizes this operation but leaves important issues open to interpretation. The thesis is composed of an introduction, two main parts and a conclusion. First two chapters of the first part deal with historical development of this legal concept. In the roman law, a contractual obligation was conceived as a "bond of law" (iuris vinculum), which implied a strictly personal nature of this relationship. However, this view started to change as soon as the roman economy shifted from agriculture towards trade and business, resulting in assignability of a contractual right. In the codification era of the 19th century, the concept of a delegation of contractual duty came in, establishing a theoretical foundation for the assignment of contract as such. The third chapter moves our attention to the modern times, focusing primarily on the assignement of contract in various European countries, United States and Japan. The emphasis is put on the theoretical discussions this legal concept has seen in...
87

Smlouva o postoupení pohledávky / Contract for the assignment of a claim

Klíma, Lukáš January 2017 (has links)
The purpose of this thesis is to try to provide comprehensive analysis of the recent legislation of contract for the assignment of a claim, compare it with former legislation, critically evaluate changes that new civil code bought to contract for the assignment of a claim and find solutions for selected legal problems that acceptance of current legislation brought to experts. The thesis is systematically divided into seven chapters. First chapter briefly define the concept of obligation and is dedicated to changes in subject of obligations based on the will of the parties. The second chapter analyses the historical development of assignment of a claim. In first part attention is paid to genesis of Roman law cessio, in later parts it analysis civil codes effective in Bohemia which contained legislation of assignment of a claim. The third chapter is devoted to subject of assignment of a claim. It analysis what can be assign and what cannot be assign. Special attention is dedicated to assignment of future claims and assignment of group of claims. The fourth chapter is devoted to contract for assignment of a claim. It analysis form of contract for assignment of a claim and essential aspects of this kind of contract. The fifth chapter is devoted to parties of contract for assignment of a claim. It...
88

The optimal assignment problem: an investigation into current solutions, new approaches and the doubly stochastic polytope

Vermaak, Frans-Willem 23 May 2011 (has links)
MSc(Eng),Faculty of Engineering and the Built Environment, University of the Witwatersrand, 2010 / This dissertation presents two important results: a novel algorithm that approximately solves the optimal assignment problem as well as a novel method of projecting matrices into the doubly stochastic polytope while preserving the optimal assignment. The optimal assignment problem is a classical combinatorial optimisation problem that has fuelled extensive research in the last century. The problem is concerned with a matching or assignment of elements in one set to those in another set in an optimal manner. It finds typical application in logistical optimisation such as the matching of operators and machines but there are numerous other applications. In this document a process of iterative weighted normalization applied to the benefit matrix associated with the Assignment problem is considered. This process is derived from the application of the Computational Ecology Model to the assignment problem and referred to as the OACE (Optimal Assignment by Computational Ecology) algorithm. This simple process of iterative weighted normalisation converges towards a matrix that is easily converted to a permutation matrix corresponding to the optimal assignment or an assignment close to optimality. The document also considers a method of projecting a matrix into the doubly stochastic polytope while preserving the optimal assignment. Various methods of projecting square matrices into the doubly stochastic polytope exist but none that preserve the assignment. This novel result could prove instrumental in solving assignment problems and promises applications in other optimisation algorithms similar to those that Sinkhorn’s algorithm finds.
89

Study on Genetic Algorithm Improvement and Application

Zhou, Yao 03 May 2006 (has links)
Genetic Algorithms (GAs) are powerful tools to solve large scale design optimization problems. The research interests in GAs lie in both its theory and application. On one hand, various modifications have been made on early GAs to allow them to solve problems faster, more accurately and more reliably. On the other hand, GA is used to solve complicated design optimization problems in different applications. The study in this thesis is both theoretical and applied in nature. On the theoretical side, an improved GA�Evolution Direction Guided GA (EDG-GA) is proposed based on the analysis of Schema Theory and Building Block Hypothesis. In addition, a method is developed to study the structure of GA solution space by characterizing interactions between genes. This method is further used to determine crossover points for selective crossover. On the application side, GA is applied to generate optimal tolerance assignment plans for a series of manufacturing processes. It is shown that the optimal tolerance assignment plan achieved by GA is better than that achieved by other optimization methods such as sensitivity analysis, given comparable computation time.
90

Essais en théorie de l’appariement et ses applications / Essays in matching theory and its applications

Combe, Julien 24 October 2017 (has links)
Cette thèse étudie l'affectation centralisée des enseignants aux écoles et un nouveau modèle d'appariement inspirée par cette dernière.Dans le premier chapitre, nous développons un modèle théorique de réaffectation afin d'étudier le problème de réaffecter des enseignants titulaires enseignant au sein d'un établissement et demandant une mutation. Le problème est similaire à celui d'affecter des élèves dans des écoles. Dans ce cas, l'algorithme à Acceptation Différée a été identifié comme étant le seul algorithme qui: i) est stable, ii) efficace et qui iii) incite les élèves à soumettre sincèrement leurs préférences. La différence principale avec le problème d'affecter des élèves aux écoles est que les enseignants ont déjà une position initiale au sein d'un établissement. On doit donc prendre en compte une contrainte additionnelle, la Rationalité Individuelle (RI): un enseignant doit être affecté dans un établissement qu'il préfère faiblement à son établissement d'origine. Pour prendre en compte cette contrainte, une modification de l'algorithme à Acceptation Différée a été identifiée dans la littérature académique et utilisé en pratique pour affecter les enseignants aux écoles en France. Nous montrons que cet algorithme modifié souffre d'un important défaut: il n'est pas efficace au sens fort. Il est en effet possible de réaffecter les enseignants aux écoles de telle sorte que: i) les enseignants obtiennent une école qu'ils préfèrent et ii) les écoles obtiennent des enseignants mieux classés. Partant de ce constat, nous identifions la classe de tous les algorithmes, les algorithmes Block-Exchange (BE), qui ne souffrent pas de ce défaut. Parmi eux, nous montrons qu'il en existe un unique qui incite les enseignants à soumettre leurs préférences sincèrement: le Teacher Optimal Block-Exchange algorithm (TO-BE). En utilisant un modèle de marché large, nous montrons théoriquement que ces algorithmes ont de meilleures performances en termes de mouvement et de bien-être des enseignants que l'algorithme actuel. Nous utilisons ensuite une base de données sur l'affectation des enseignants aux écoles du secondaire en France en 2013 pour quantifier les gains possibles que nos algorithmes peuvent apporter. Dans un cadre de réaffectation pur sans enseignant néotitulaire et places vacantes, nous montrons qu'il est possible de plus que double le nombre d'enseignants obtenant une nouvelle affectation.Dans le second chapitre, nous concevons un algorithme pratique, inspiré de nos résultats du chapitre précédent, pour la procédure française d'affectation des enseignants du secondaire. Plus globalement, cette conception a également pour but de fournir un outil face à deux problèmes importants communs aux pays de l'OCDE: i) le manque d'attractivité de la profession enseignants et ii) les importantes inégalités de réussites des élèves issus de milieux sociaux différents. Nous considérons l'ensemble du marché français composé des enseignants titulaires demandant une réaffectation, les enseignants sans affectation initiale et des places vacantes. Améliorer la mobilité des enseignants permet de leur donner de meilleures perspectives de carrière ce qui peut potentiellement attirer plus d'entrants dans la profession. Mais cette mobilité accrue peut entrainer l'affectation de plus d'enseignants peu expérimentés au sein d'académies déjà très défavorisées, affectant in fine la réussite des élèves au sein de celles-ci. Nous proposons un algorithme flexible qui permet de mieux contrôler le mouvement et la distribution des enseignants au sein de régions, notamment celles très désavantagées. En utilisant les données françaises d'affectation de 2013, nous simulons plusieurs scénarios contre factuels et montrons que notre algorithme peut prendre en compte plusieurs objectifs de politique publique. / This thesis studies the centralized assignment of teachers to schools and a new matching framework inspired by it. In the first chapter, we develop a theoretical model of reassignment to study the problem of reassigning tenured teachers who already have a position and are willing to move to another school. The problem is similar to the one of assigning students to schools. In this case, the well known Deferred Acceptance algorithm has been identified as the only algorithm that: i) is stable ii) efficient and iii) gives incentives to students to report their true preferences. The main difference with the problem of assigning students to schools is that teachers have an initial assignment. One has to consider an additional constraint, Individual Rationality (IR): a teacher must receive a school that he weakly prefers to his initial one. To incorporate this constraint, a modification of the Deferred Acceptance algorithm has been identified in the academic literature and used in practice to assign teachers to schools in France. We show that this modified algorithm has a serious drawback: it is not efficient in a strong sense. Indeed, it is possible to reassign teachers to schools such that both: i) teachers obtain a school that they prefer and ii) schools are assigned teachers that they rank higher. Thus, we identify the class of all algorithms, the Block-Exchange (BE) algorithms, that do not suffer from this drawback. Among them, we show that there is a unique one that gives good incentives to teachers to report their true preferences, the Teacher Optimal Block-Exchange algorithm (TO-BE). In using a large market setting, we theoretically show that these algorithms perform better in terms of movement and welfare for teachers than the currently used one. We then use a dataset on the assignment of teachers to schools in France in 2013 to quantify the possible gains that can bring our algorithms. In a reassignment setting with no newly tenured teachers or empty seats, we show that we can more than double the number of teachers obtaining a new assignment. In the second chapter, we aim to design a practical algorithm, inspired by our findings in the previous chapter, for the French assignment system of teachers to schools. More generally, this design also aims to provide a tool about two important issues common to OECD countries: i) the lack of attractiveness of the teaching profession and ii) the high achievement inequality between students from different social backgrounds. We consider the complete French market composed of tenured teachers looking for a reassignment, newly tenured teachers with no initial assignment and empty positions. In improving the mobility of teachers, one can give them better career perspectives and so potentially attract more teachers into the profession. But in doing so, it can also hurt deprived regions in assigning more teachers with low experience to them and ultimately the students from these regions. We propose a flexible algorithm that allows to better control the movement and distribution of teachers across regions, especially deprived ones. Using the data of the French assignment of teachers in 2013, we simulate several counter factuals and show that our algorithm can accommodate a wide range of policy objectives.

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