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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.
101

How furniture shopping couldchange through omni-channelretailing and the use of technology-based innovations / Hur handeln av möbler kan förändras genom användningen av omnikanaler och teknologiska innovationer

UDDENFELDT, JOAKIM January 2014 (has links)
Syftet med denna forskning är att få en bättre förståelse för de faktorer som påverkar konsumenternas beslutsfattande vid köp av möbler och hur Omni - kanaler och teknologiska innovationer kan bidra till möbelindustrin och hur det påverkar de olika marknadsföringskanalerna och hur det i slutändan kan förändra upplevelsen för kunden. Den teori som har använts i denna studie omfattar områdena Omni  kanaler, marknadsföring och detaljhandel, allmän detaljhandel och dess kundupplevelse , beslut och konsumentbeteende vid köp av möbler, hur sociala medier påverkar marknadsföringen och teknologiska innovationer inom möbelindustrin. För att förstå hur omni-kanaler och teknologiska innovationer kan ändra kundupplevelsen och marknadsföringskanalerna för möbler, har tre semistrukturerade intervjuer och en undersökning gjorts. Resultatet av denna forskning kommer fram till att ha en teknikbaserad innovation som t.ex. InsideMaps gör köpupplevelsen mer fördelaktigt för både hedoniska och utilitaristiska konsumenter samt skiftar marknadsföringskanalerna åt mer direkt försäljning över Internet . Med hjälp av Internet, kan tillverkaren / återförsäljaren utvidga sitt varumärke till fler människor . Detta beror på det faktum att det blir lättare för kunderna att köpa möbler då de kan visualisera de möbler de köper innan och hur de skulle se ut i sitt eget hem . Men för att detta ska fungera på ett bra sätt är det viktigt att användarupplevelsen är bra. Genom att använda en teknikbaserad innovation kommer även leda till att en tillverkares - återförsäljares Omni - kanal och marknadsföring blir starkare, eftersom sådana innovationer stärker och ger en konkurrensfördel gentemot andra tillverkare - återförsäljare. / The objective of this research is to gain a better understanding of the factors involved in consumer decision making for buying home furniture and how Omni-channel retailing and technology-based innovation can help this industry to enhance its marketing channels and how it ultimately change the retail experience for the customer. The theoretical framework that has been used in this study covers the areas of Omni-channel marketing and retailing, general retailing customer experience, decision and consumer behaviors in retail furniture settings, how social media influences marketing and technology-based innovations within the furniture industry. In order to understand how the retail experience and the marketing channels of furniture shopping change through Omni-channel retailing and the use of technology-based innovations, three semi-structured interviews and a survey were done. The results of this research concludes that having a technology-based innovation such as InsideMaps will make the shopping experience more beneficial for both hedonic and utilitarian shoppers as well as shifting the marketing channels to more direct selling over the Internet. With the help of Internet, producers/retailers can extend their brand to more people. This is due to the fact that it will be easier for customers to buy furniture as they can visualize the furniture they are buying and how they would look like in their own home. However, for this to work it is important that the user experience is good. By using a technology-based innovation will also make a producers-retailers Omnichannel marketing stronger, as such innovation strengthen and gives a competitive advantage over other producers-retailers that uses Omni-channel marketing.
102

Effective Use of Network Coding in Multi-hop Wireless Networks

Chi, Yang January 2013 (has links)
No description available.
103

Analytical Model for Capacity and Delay Optimization in Wireless Mesh Networks

Fu, Weihuang January 2010 (has links)
No description available.
104

A model of reciprocal effects of multi-channel retailers' offline and online brand images: application to multi-channel specialty apparel retailing

Kwon, Wi-Suk 02 August 2005 (has links)
No description available.
105

GPS Antenna and Receiver for Small Cylindrical Platforms

Svendsen, Andrew S. C. 19 June 2012 (has links)
No description available.
106

Improving the Capacity in Wireless Ad Hoc Networks through Multiple Channel Operation: Design Principles and Protocols

Gong, Michelle Xiaohong 07 July 2005 (has links)
Despite recent advances in wireless local area network (WLAN) technologies, today's WLANs still cannot offer the same data rates as their wired counterparts. The throughput problem is further aggravated in multi-hop wireless environments due to collisions and interference caused by multi-hop routing. Because all current IEEE 802.11 physical (PHY) standards divide the available frequency into several orthogonal channels, which can be used simultaneously within a neighborhood, increasing capacity by exploiting multiple channels becomes particularly appealing. To improve the capacity of wireless ad hoc networks by exploiting multiple available channels, I propose three principles that facilitate the design of efficient distributed channel assignment protocols. Distributed channel assignment problems have been proven to be <i>NP</i>-complete and, thus, computationally intractable. Though being a subject of many years of research, distributed channel assignment remains a challenging problem. There exist only a few heuristic solutions, none of which is efficient, especially for the mobile ad hoc environment. However, protocols that implement the proposed design principles are shown to require fewer channels and exhibit significantly lower communication, computation, and storage complexity, compared with existing approaches. As examples, I present two such protocols that build on standard reactive and proactive routing protocols. In addition, I prove the correctness of the algorithms and derive an upper bound on the number of channels required to both resolve collisions and mitigate interference. A new multi-channel medium access control (MC-MAC) protocol is also proposed for multi-hop wireless ad hoc networks. MC-MAC is compatible with the IEEE 802.11 medium access control (MAC) standard and imposes the minimum system requirements among all existing multi-channel MAC protocols. In addition, simulation results show that even with only a single half-duplex transceiver, MC-MAC, by exploiting multiple channels, can offer up to a factor of four improvement in throughput over the IEEE 802.11 MAC protocol. The reduction in delay is even more significant. Therefore, the MC-MAC protocol and the accompanying distributed channel assignment protocols constitute an effective solution to the aforementioned performance problem in a multi-hop wireless network. Finally, I generalize the cross-layer design principle to more general networking functions and present a network architecture to motivate and facilitate cross-layer designs in wireless networks. A literature survey is provided to validate the proposed cross-layer design architecture. Current cross-layer design research can be categorized into two classes: joint-layer design using optimization techniques, and adaptive techniques based on system-profile and/or QoS requirements. Joint-layer design based on optimization techniques can achieve optimal performance, but at the expense of complexity. Adaptive schemes may achieve relatively good performance with less complexity. Nevertheless, without careful design and a holistic view of the network architecture, adaptive schemes may actually cause more damage than benefit. / Ph. D.
107

Multi-Channel Constant Current (MC3) LED Driver for Indoor LED Luminaries

Wu, Haoran 07 December 2011 (has links)
Recently, as a promising lighting source, light-emitting diodes (LEDs) have become more and more attractive and have great opportunity to replace traditional lighting sources - incandescent, fluorescent and HID because of the advantages such as high luminous efficacy, long lifetime, quick on/off time, wide color gamut, eco-friendly etc. Based on the research from U.S. Department of Energy, over 30% of total electric consumption in U.S. each year is for lighting, 75% of which are for indoor lighting (including both residential and commercial buildings). In the indoor LED lighting application, to provide multiple current source outputs for multiple LED strings, traditional solutions usually adopt a two-stage structure, which is complicated and cost-ineffective. How to design a simple, low-cost and efficient LED driver with multiple current source outputs is in great demand and really challenging. In this thesis, a single-stage multi-channel constant current (MC3) LED driver structure has been proposed. Multiple transformer structure is utilized to provide multiple current source outputs. The current control scheme is also simple - only one LED string current is sensed and controlled; other strings' currents are cross regulated. Firstly, a PWM half bridge topology is chosen to implement the proposed single-stage MC3 LED driver concept. In order to analyze the current cross regulation, a general model is derived. The circuit has been simulated under various LED load conditions to verify its good current sharing capability. In order to further improve efficiency, simplify the driver's complexity and reduce cost, a LLC resonant topology is also investigated. LLC current gain characteristic has been derived by considering LED's i-v character and a design procedure is developed. A 100 kHz, 200 W, 4-string MC3 LLC LED driver is designed and tested. The experimental results show that the driver can maintain constant current output within the whole input and output variations, achieve good efficiency and realize current sharing under both balanced and unbalanced LED conditions. The dimming function can also be realized through frequency modulation method and burst mode control method. As a conclusion, a single-stage MC3 LED driver concept is proposed and implemented with two topologies. The proposed idea provides a simple, low-cost and efficient solution for indoor LED lighting application with multiple LED string configuration. It also has good current sharing capability and robustness to LED forward voltage variations or short failures. / Master of Science
108

Link-directionalities in carrier sense wireless networks

Ng, Ping Chung January 2008 (has links)
In this thesis, research is described which leads to the proposal of a link-directionality-based dual channel MAC (Medium Access Control) protocol (DCP) for carrier sense wireless ad hoc networks. It attempts to double the capacities of such networks using an industrial standard (the single-channel IEEE 802.11 protocol) as a benchmark. Simulations show that the proposed scheme can increase the capacities to more than 1.7 times of the single-channel IEEE 802.11 protocol in large-scale random network topologies. The algorithm, however, requires extra radio spectrum resource which could be costly. In addition to DCP, a signal-to-interference ratio comparison algorithm (SCA) is proposed to further release the protocol constraints imposed by the virtual carrier-sensing mechanism. Interestingly, while the capacity of the pure DCP decreases when link lengths are short, the capacity of the pure SCA increases when link lengths are short. The two algorithms compensate for the downside of each other to bring about a more uniform capacity improvement. Simulations show that the integrated scheme can further increase the network throughputs to more than 2.13 times in random topologies. This thesis also clarifies inter-link interference in wireless ad-hoc networks by using link-directional interference graphs (l-graph). By colouring the l-graphs, independent data streams obtained by Multi-Carrier Code Division Multiple Access (MC-CDMA) are assigned for transmitting up-link and down-link traffic separately in order to eliminate the hidden-node and exposed-node problems in wireless local area networks (WLAN). Finally, a generic approach for capacity analysis is proposed to show that the concept of link-directionality can also be adopted with other network models, protocols and parameter settings. However, in certain scenarios where links are densely packed together, the advantage of using link-directionality could be diminished. Therefore, the proposed generic approach for capacity analysis allows one to determine whether channel allocations according to link-directionalities should be applied to a given network.
109

Méthodes de spatialisation sonore et intégration dans le processus de composition

Néron Baribeau, Raphaël 07 1900 (has links)
L’espace est un élément peu exploré en musique. Méconnu des compositeurs, il n’est généralement pas pensé comme paramètre musical « composable ». Pourtant si la musique peut être perçue comme une organisation et une succession d’éléments dans le temps, pourquoi ne pourrait-elle pas l’être aussi dans l’espace? Ce travail se veut en quelque sorte un pont entre la recherche et la pratique, qui se construit par la synthèse de l’information que j’ai pu trouver sur chacune des quatre méthodes de spatialisation abordées ici. Dans un premier temps, je traiterai de leur développement, leur fonctionnement et des possibilités d’intégration de ces méthodes dans le processus de composition musicale, notamment en discutant les outils disponibles. Dans un second temps, les pièces Minimale Sédation et Fondations, toutes deux composées en octophonie seront discutées. J’expliquerai leurs processus de composition à travers les intentions, les techniques d’écriture et les outils qui ont menés à leurs créations. / Space is a parameter of sound that is relatively unexplored in music. Misunderstood by composers, it is not generally thought of as "composable" musical parameter. Yet if music can be seen as an organization and a succession of elements in time, why could it not also be in space? This work is intended to somehow bridge the gap between research and practice, by synthesizing the information I could find on each of the four sound spatialization methods discussed here. As a first step, I will discuss their development, operation and integration capabilities in the process of musical composition, as well as the tools available. In a second step, the work Minimale Sédation and Foundations, both composed in eight channels will be discussed. I will explain their process of composition through intentions, writing techniques and tools that have led to their creations. Keywords
110

Contribution à l'étude des architectures de récepteurs large bande multi-canaux / Study of multi-channel wideband receiver architectures.

Lesellier, Amandine 02 July 2013 (has links)
Cette thèse est le fruit d'un partenariat entre la BL TVFE de NXP Semiconductors et l'ESIEE dans le cadre d'une thèse CIFRE. Le but est d'apporter une solution qui permette la réception de plusieurs canaux pour le câble. Ce sujet est lié à la problématique de numérisation large bande. Dans la première partie, nous faisons un état-de-l'art sur les convertisseurs analogiques-numériques (CAN), sur les architectures parallèles (entrelacement temporel et bancs de filtres hybrides (BFH)), et sur les méthodes d'échantillonnage (passe-bande et complexe). Puis, nous étudions une architecture composée d'un banc de filtres analogiques et un banc de CANs. Nous cherchons à réduire surtout le taux d'échantillonnage. Nous comparons notre solution à un CAN large bande performant, avec notre fonction de coût. L'un des avantages de cette architecture est que tous les composants sont faisables, même les CANs, et qu'il est possible d'éteindre des sous-bandes pour diminuer la consommation. Cette solution est intéressante pour le moment mais n'est pas compétitive en termes de consommation et de surface. Nous proposons une alternative dans la partie 3, avec les BFH. Nous étudions cette architecture, en gardant à l'esprit la faisabilité de la solution. Nous avons choisi un BFH à deux voies, avec un filtre analogique passe-bas et un passe-haut. Puis, nous proposons un algorithme d'optimisation des filtres de synthèse pour atteindre nos objectifs de distorsion et de réjection de repliement. Une identification des filtres analogiques est aussi présentée. Finalement, une réalisation physique prouve le concept et valide les limitations théoriques de cette architecture / This thesis is a partnership between the BL TVFE of NXP Semiconductors and ESIEE. Its goal is to provide a solution to multi-channel reception for cable network. This is linked to the problematic of broadband digitization. In the first part, the state-of-the art of ADCs, parallel architectures (TI and HFB) and sampling methods (bandpass sampling and complex sampling) is recalled. Then we study an architecture called RFFB with a bank of analog filters and a bank of ADCs. We try to reduce the constraints on ADCs, especially the sampling rate with the different sampling. We propose an interesting solution to broadband digitization and compare this solution to a challenging wideband ADC, using the cost function we introduce. This architecture has the major advantage that all the components are feasible, even the ADCs, and it is possible to switch-off subbands to save power. It could be a good solution at the present time but it is not competitive in terms of power consumption and surface. An alternative is proposed in Part 3, where we study Hybrid Filter Banks. It is interesting to study this architecture with realization feasibility in mind. This is why we select a 2-channel HFB with a lowpass filter and a highpass filter as analog filters. Then we propose an efficient optimization algorithm to find the best synthesis filters and reach our targets of distortion and aliasing rejection. An identification of analog filters is also suggested to cope with the issue of sensitivity to analog errors. Finally, a physical realization proves the concept of aliasing rejection and confirms the theoretical issues of this architecture

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