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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.
241

Stochastic last-mile delivery problems with time constraints

Voccia, Stacy Ann 01 July 2015 (has links)
When a package is shipped, the customer often requires the delivery to be made within a particular time window or by a deadline. However, meeting such time requirements is difficult, and delivery companies may not always know ahead of time which customers will need a delivery. In this thesis, we present models and solution approaches for two stochastic last-mile delivery problems in which customers have delivery time constraints and customer presence is known in advance only according to a probability distribution. Our solutions can help reduce the operational costs of delivery while improving customer service. The first problem is the probabilistic traveling salesman problem with time windows (PTSPTW). In the PTSPTW, customers have both a time window and a probability of needing a delivery on any given day. The objective is to find a pre-planned route with an expected minimum cost. We present computational results that characterize the PTSPTW solutions. We provide insights for practitioners on when solving the PTSPTW is beneficial compared to solving the deterministic analogue of the problem. The second problem is the same-day delivery problem (SDDP). The SDDP is a dynamic and stochastic pick-up and delivery problem. In the SDDP, customers make delivery requests throughout the day and vehicles are dispatched from a warehouse or brick and mortar store to serve the requests. Associated with each request is a request deadline or time window. In order to make better-informed decisions, our solution approach incorporates information about future requests into routing decisions by using a sample scenario planning approach with a consensus function. We also introduce an analytical result that identifies when it is beneficial for vehicles to wait at the depot. We present a wide range of computational experiments that demonstrate the value of our approaches.
242

Elementos del Windows display en relación con la intención de compra de videojuegos en Centros Comerciales en mujeres aficionadas de Lima Metropolitana / Elements of Windows display in relation to the purchase intention in video games in Shopping Centers for amateur women in Metropolitan Lima

Romero Vizarreta, Juan De Dios 02 July 2019 (has links)
En base al constante crecimiento del mercado de videojuegos, diversas marcas buscan incorporar estrategias para diferenciarse del resto y poder potenciar la intención de compra de las personas en su beneficio, tal como las tiendas Phantom y Lawgamers, quienes buscan obtener la mayor cantidad de ventas posibles. Por tal motivo, la presente investigación tiene como finalidad encontrar la relación entre las variables de los elementos del windows display e intención de compra de videojuegos en Centros Comerciales en mujeres aficionadas de Lima Metropolitana. Así mismo, el trabajo de investigación busca responder a la pregunta de investigación formulada, la cual debate acerca de cuál de los elementos del windows display son más influyentes en la intención de compra y, así responder la hipótesis propuesta, la cual menciona que el sticker o la estatua tienen mayor influencia en la intención de compra. Además, esta investigación esta compuesta por una parte cualitativa y cuantitativa, la cual es de tipo correlacional porque se busca comprobar la relación de una variable con otra y con técnica mixta. Así pues, los resultados obtenidos de la investigación revelaron que el sticker y la estatua no son los elemento del windows display que más influyente en la intención de compra en el público objetivo. Por otro lado, el windows display cuenta con otros elementos, los cuales fueron jerarquizados según su grado de importancia, siendo los más importantes producto, color, sticker, iluminación y estatua. Por ultimo, se pudo concluir que el producto es el elemento del windows display que más influyente en la intención de compra en el público objetivo. / Based on the constant growth of the videogame market, several brands seek to incorporate strategies to differentiate themselves from the rest and to maximize the intention of people to purchase on their benefit, Stores like Phantom and Lawgamers, who seek to obtain as much sales as possible. For this reason, the purpose of this research is to find the relationship between The variable elements of windows display and the intention of buying videogames in shopping centers for amateur women in Metropolitan Lima. Likewise, the research work seeks to answer the question formulated, that discusses which of the elements windows display are most influential in the purchase intention and, answer the proposed hypothesis, which mentions that the sticker or the statue have a greater influence on the purchase intention. In addition, this research is composed of a qualitative and quantitative part, which is correlated because it seeks to verify the relationship of one variable with another and with mixed media. Thus, the results obtained from the investigation revealed that the sticker and the statue are not elements of the windows display that most influential in the purchase intention in the target audience. On the other hand, the windows display has other elements, which were ranked according to its importance, being the most important product, color, sticker, lighting, statue. Finally, it can be concluded that the product is the element of the windows display that is the most influential in the purchase intention in the target audience. / Trabajo de investigación
243

Om bildningens utmaningar och möjligheter i den svenska grundskolan

Kjellsson, Anders January 2022 (has links)
The aim of this study is to develop new knowledge about the challenges and possibilities of Bildung in the Swedish compulsory school. Based on a qualitative analysis of five elite interviews with five theorists of Bildung, this study is inspired by curriculum theory and, in particular, the key analytical concepts of curriculum models, frame factors and room for freedom The results make visible both challenges and possibilities for Bildung in the Swedish compulsory school.  First, through a thematic analysis, five themes were identified: i) Bildung as an open process; ii) Bildung in relation to coherence and overview; iii) Bildung and meaning making; iv) Bildung in education; and v) Bildung as resistance. This thematic analysis has shown that tensions exist between Bildung and the measurable results that are the focus in the Swedish school. Furthermore, a one-sided alignment to measurability tends to neglect several dimensions of Bildung.  Second, the outcomes from the thematic analysis were considered in light of the curriculum theory framework in the form of an additional analysis based on three theoretical curriculum models. Using the theoretical concepts frame factors and room for freedom, the analysis demonstrates that various curriculum models, in different ways, both restrict Bildung and make it possible. Despite this, the results illustrate how Bildung, to a greater or lesser extent, can be operationalized through different curriculum models.  The third analysis reveals a shift in the understanding of Bildung in the Swedish school, from something differential to something for every pupil. The final results are visualized as three “windows” of Bildung, each of which presents how Bildung can be a natural component of the Swedish compulsory school: i) a democratized and expanded view of Bildung; ii) a fluid dialogue between the subjective and objective dimensions of Bildung; and iii) Bildung as resistance.  This study contributes to a current and forward-looking discussion about the role of Bildung, with a special focus on the Swedish compulsory school; however, it is also of relevance outside the Swedish context.
244

Strömmar av vatten och politik - en studie om policyprocesser och anpassning.

Åkesdotter, Marie January 2008 (has links)
<p>One of the distinguishing features of successful societies is the ability to adapt to change, both</p><p>social but also natural changes like climate change. Climate change is a complex, dynamic,</p><p>non-linear process with a great deal of uncertainty concerning the time perspective, risks and</p><p>consequences. A combination of factors like climate change, geographical vulnerability, a</p><p>densely populated and highly built up coast line along with factors like deficient handling of</p><p>surface runoff and a large usage of ground water leads to an increasingly vulnerable society. It</p><p>also puts a greater pressure on the society to have preventive measures in place.</p><p>The number of actors working with preparing society to the expected impacts of climate</p><p>change and variability is increasing. However more than half of Sweden’s municipalities do</p><p>not consider changing climatic conditions when planning, and many times even allow the</p><p>construction of new living areas in known climatically vulnerable areas. Certain geographical</p><p>areas in Sweden are characterized by environmental problems which enhance the predicted</p><p>effects of climate change. The coast of Scania (Skåne) is one such area, where people for a</p><p>long time have had to adjust to conditions like coastal erosion, recurring high tides, low lying</p><p>areas and sinking land.</p><p>The following study elaborates the politics of adaptive capacity. It is based on a comparative</p><p>case study of two different policy processes regarding adjustments to climatic conditions in</p><p>the coastal municipalities of Vellinge and Lomma in south-western Scania. In other words,</p><p>this study explores the underlying factors that can explain what drives anticipatory measures</p><p>to strengthen the ability and possibility to handle effects related to climate change. The</p><p>theoretical framework consists of theories regarding policy changes in social ecological</p><p>systems, and adaptation to climate. Structural actor based perspective, as well as system</p><p>oriented and process oriented have been applied.</p><p>The results are based on 14 interviews with key politicians, officials and stakeholders from</p><p>non-governmental organizations. The study is also based on reports, a citizen’s survey from</p><p>Statistics Sweden (SCB), newspaper articles, municipal documents, web sites and literature.</p><p>The results show that the municipality of Vellinge implemented adaptation strategies years</p><p>before Lomma municipality. Policy change was triggered by observed vulnerabilities in</p><p>ecological systems which affected the social systems. It resulted in an intense debate (a</p><p>window of opportunity), which in turn opened a policy window.</p><p>The driving forces in policy process are central actors and shadow networks with access to</p><p>knowledge. The results show that knowledge and understanding of ecological systems is</p><p>essential for policy changes in climate adaptations. Research is needed, but research by itself</p><p>will not be sufficient, research and knowledge must be transferred to decision-makers.</p><p>Knowledge transferring is even important for officials and public. That means that an</p><p>understanding of ecological systems is necessary for forming attitudes and for planning a</p><p>society with the ability to meet climate change and the insecurities which are connected with</p><p>it.</p>
245

Utvärdering av produkter för säker autentisering i Windowsmiljö / Evaluation of secure authentication products in a Windows environment

Backman, Mattias January 2004 (has links)
<p>In this report hardware based alternatives to password authentication in a Windows domain are evaluated for the needs of a certain company. In order to investigate the demands on such alternatives interviews with people concerned have been carried out. The demands which resulted from the interviews have been used to select types of hardware tokens for evaluation. Two products which offer authentication with smart cards and USB tokens have been selected and closer evaluated. These are RSA Passage which offers both hardware options and Rainbow iKey which uses USB tokens. Both products are evaluated based on the demands and additional evaluation criteria. The information from the evaluations is used to compare the products.</p>
246

Life Cycle Cost för datanätverk -en ekonomisk jämförelse av operativsystem / Life Cycle Cost for a computer network -an economical comparison between operating systems

Liljedahl, Magnus, Näsholm, Robert January 2000 (has links)
<p>Bakgrund: Företag behöver i dagens samhälle robusta och pålitliga datasystem. För att bygga ett väl fungerande nätverk måste dessa baseras på bra operativ- systemprogramvara. Den fria programvaran, Linux, har stärkt konkurrensen på marknaden för operativsystem. Att konkurrensen hårdnat gör det intressant att undersöka ifall kostnaderna för anskaffning och användning skiljer sig åt mellan olika operativsystem.</p><p>Syfte: Syftet med detta arbete är att skapa en LCC-modell vilken skall appliceras på operativsystem i datanätverk. Vidare skall vi använda modellen till att jämföra totalkostnaden för att anskaffa och nyttja operativsystem i datanätverk under nätverkets livstid.</p><p>Genomförande: För att uppnå vårt syfte har vi genomfört personliga intervjuer med ekonomi- och dataansvariga på tio olika organisationer. Utifrån dessa intervjuer har vi tillsammans med litteraturstudier konstruerat en LCC-modell. Denna har vi sedan använt för att skapa en reviderad LCC-modell som vi ansatt för att jämföra totalkostnaden för att nyttja Linux respektive Windows NT i sitt nätverk.</p><p>Resultat: Resultatet är en LCC-modell som kan användas i en rad olika syften. Vår reviderade modell visade att ett renodlat Linuxsystem är ett billigare alternativän ett renodlat Windows NT-system. Behovet har dock visat sig vara viktigare än priset vid val av system. För att reducera kostnader är det viktigt att satsa på utbildning och kvalitet.</p>
247

Online 3D presentationer : Vilken teknik är mest lämplig idag för små och medelstora företag?

Tollerud, Ian January 2007 (has links)
<p>Denna rapport beskriver och undersöker olika sätt att använda online 3D i webbpresentationer. 3D ställs emot vad som ibland brukar kallas 2,5D (Man fotograferar en produkt ur olika vinklar för att få en serie med bilder som kan ge en fiktiv 3D upplevelse). Rapporten ger bakgrund och historia över online 3D teknologi, ger en översikt över marknaden för online produktpresentationer idag och försöker ge en ögonblicksbild av situationen i andra kvartalet 2007 över en snabb föränderlig marknad. Fyra olika 3D system ställs mot varandra med hjälp av praktiska kodexempel och avslutas med en helhetslösning för dynamisk generering av webbsidor. Målgruppen är programmerare och webbutvecklare som tar fram material för små och medelstora företag.</p>
248

VPN : Virtual Private Network i Windows 2000

Norin, Anders, Ohlsson, Henrik January 2002 (has links)
No description available.
249

Life Cycle Cost för datanätverk -en ekonomisk jämförelse av operativsystem / Life Cycle Cost for a computer network -an economical comparison between operating systems

Liljedahl, Magnus, Näsholm, Robert January 2000 (has links)
Bakgrund: Företag behöver i dagens samhälle robusta och pålitliga datasystem. För att bygga ett väl fungerande nätverk måste dessa baseras på bra operativ- systemprogramvara. Den fria programvaran, Linux, har stärkt konkurrensen på marknaden för operativsystem. Att konkurrensen hårdnat gör det intressant att undersöka ifall kostnaderna för anskaffning och användning skiljer sig åt mellan olika operativsystem. Syfte: Syftet med detta arbete är att skapa en LCC-modell vilken skall appliceras på operativsystem i datanätverk. Vidare skall vi använda modellen till att jämföra totalkostnaden för att anskaffa och nyttja operativsystem i datanätverk under nätverkets livstid. Genomförande: För att uppnå vårt syfte har vi genomfört personliga intervjuer med ekonomi- och dataansvariga på tio olika organisationer. Utifrån dessa intervjuer har vi tillsammans med litteraturstudier konstruerat en LCC-modell. Denna har vi sedan använt för att skapa en reviderad LCC-modell som vi ansatt för att jämföra totalkostnaden för att nyttja Linux respektive Windows NT i sitt nätverk. Resultat: Resultatet är en LCC-modell som kan användas i en rad olika syften. Vår reviderade modell visade att ett renodlat Linuxsystem är ett billigare alternativän ett renodlat Windows NT-system. Behovet har dock visat sig vara viktigare än priset vid val av system. För att reducera kostnader är det viktigt att satsa på utbildning och kvalitet.
250

New Blind Constant Modulus Sliding Windows GSC-RLS Algorithm for DS-CDMA Receiver with Min/Max Criterion

Luo, Yin-chen 30 August 2007 (has links)
The code division multiple access (CDMA) system implemented by the direct-sequence (DS) spread spectrum (SS) technique is one of the most promising multiplexing technologies for the wireless communications services. The SS communication adopts a technique of using much wider bandwidth necessary to transmit the information over the channel, and has been proposed for third generation broadband wireless access. The capacity and performance of the DS-CDMA system are mainly limited by the multiple access interference (MAI) and the inter-symbol-interference (ISI) caused by the multipath-fading channel. To circumvent the above-mentioned problems many adaptive multiuser detectors, for instance the minimum mean square error (MMSE) and the minimum output energy (MOE) criteria, subject to certain constraints, have been proposed. Since the LCMV criterion is the linearly constrained (LC) version of MOE, it is high sensitivity to the channel mismatch caused by the unreliable estimation. In order to deal with this problem, the LC constant modulus (LCCM) criterion was considered to avoid capturing the interfering user instead of the desired user when the power of interfering user is much higher than the desired user. In this thesis, based on the Min/Max criterion we propose a novel blind LCCM recursive least-square (RLS) algorithm, with the generalized side-lobe canceller (GSC) structure, named as the CM GSC-RLS algorithm, to effectively alleviate the effect of MAI and ISI for DS-CDMA receiver, for time-varying channel. Due to the variation of channel at the receiver, the desired user amplitude or power is not available and has to be estimated. To solve this problem, we propose a simple scheme to estimate the parameter of constant modulus, adaptively, associated with the CM GSC-RLS algorithm. With the new proposed algorithm, the amplitude variation of desired user, due to changing characteristics of channel, can be tracked, effectively. Thus, better performance achievement, in terms of output signal-to-interference-plus-noise ratio (SINR) and bit error rate (BER), over the conventional GSC-RLS algorithms can be expected.

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