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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.
51

Structuring communication in the architectural forum for on-line design proefschrift ... /

Donker, Pieter Alexander, January 1900 (has links)
Proefschrift--Technische Universiteit Delft, 1996. / Includes bibliographical references (p. 149-159) and indexes.
52

The impact of variable data print on usability in design /

Wells, William. January 2007 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 99-101).
53

Design manuál a marketingová komunikace outdoorové firmy / Design Manual and Marketing Communication of Outdoor Company

Süssová, Zuzana January 2015 (has links)
Magister thesis is aimed at basic design components creation for the new company operating in the field of selling outdoor clothing. With regard to design creation it will be also marketing communication designed. As particular objectives of this thesis there will be analysis of cultural background made, follow-up market segmentation and other components of marketing mix designed. As a result should be proposal of complex marketing as the design elements and relevant marketing communication. It should be designed with regard to the company and market conditions.
54

Design of Power-Efficient Optical Transceivers and Design of High-Linearity Wireless Wideband Receivers

Zhang, Yudong January 2021 (has links)
The combination of silicon photonics and advanced heterogeneous integration is promising for next-generation disaggregated data centers that demand large scale, high throughput, and low power. In this dissertation, we discuss the design and theory of power-efficient optical transceivers with System-in-Package (SiP) 2.5D integration. Combining prior arts and proposed circuit techniques, a receiver chip and a transmitter chip including two 10 Gb/s data channels and one 2.5 GHz clocking channel are designed and implemented in 28 nm CMOS technology. An innovative transimpedance amplifier (TIA) and a single-ended to differential (S2D) converter are proposed and analyzed for a low-voltage high-sensitivity receiver; a four-to-one serializer, programmable output drivers, AC coupling units, and custom pads are implemented in a low-power transmitter; an improved quadrature locked loop (QLL) is employed to generate accurate quadrature clocks. In addition, we present an analysis for inverter-based shunt-feedback TIA to explicitly depict the trade-off among sensitivity, data rate, and power consumption. At last, the research on CDR-based​ clocking schemes for optical links is also discussed. We introduce prior arts and propose a power-efficient clocking scheme based on an injection-locked phase rotator. Next, we analyze injection-locked ring oscillators (ILROs) that have been widely used for quadrature clock generators (QCGs) in multi-lane optical or wireline transceivers due to their low power, low area, and technology scalability. The asymmetrical or partial injection locking from 2 phases to 4 phases results in imbalances in amplitude and phase. We propose a modified frequency-domain analysis to provide intuitive insight into the performance design trade-offs. The analysis is validated by comparing analytical predictions with simulations for an ILRO-based QCG in 28 nm CMOS technology. This dissertation also discusses the design of high-linearity wireless wideband receivers. An out-of-band (OB) IM3 cancellation technique is proposed and analyzed. By exploiting a baseband auxiliary path (AP) with a high-pass feature, the in-band (IB) desired signal and out-of-band interferers are split. OB third-order intermodulation products (IM3) are reconstructed in the AP and cancelled in the baseband (BB). A 0.5-2.5 GHz frequency-translational noise-cancelling (FTNC) receiver is implemented in 65nm CMOS to demonstrate the proposed approach. It consumes 36 mW without cancellation at 1 GHz LO frequency and 1.2 V supply, and it achieves 8.8 MHz baseband bandwidth, 40dB gain, 3.3dB NF, 5dBm OB IIP3, and −6.5dBm OB B1dB. After IM3 cancellation, the effective OB-IIP3 increases to 32.5 dBm with an extra 34 mW for narrow-band interferers (two tones). For wideband interferers, 18.8 dB cancellation is demonstrated over 10 MHz with two −15 dBm modulated interferers. The local oscillator (LO) leakage is −92 dBm and −88 dB at 1 GHz and 2 GHz LO respectively. In summary, this technique achieves both high OB linearity and good LO isolation.
55

High-Performance Reconfigurable Radio-Frequency Integrated-Circuit Receiver Architectures for Concurrent Signal Reception

Han, Guoxiang January 2021 (has links)
The ever-increasing demand for wireless throughput requires modern handset receivers to aggregate signals from multiple non-contiguously allocated RF carriers. This poses significant receiver design challenges, including concurrent signal reception, RF input interface, out-of-band (OB) linearity, and suppression of spurious responses. Commercial solutions use external antenna switches and off-chip RF multiplexers to provide non-tunable, narrowband filtering and impedance matching. The RF signal is then divided into separate signal chains, each with a dedicated receiver for signal reception. Although this solution allows the selection of any carrier combinations supported by the available RF filters, as the number of aggregation band combinations increases, the scale of the passive front-end module grows rapidly, leading to increased system complexity, extra signal loss, and degraded performance. This thesis presents the design and implementation of two receiver architectures that support reconfigurable operations and flexible, concurrent reception from two inter-band carriers with a tuned RF interface. We first present a multi-branch receiver with modulated mixer clocks (MMC). It unifies the functions of single-carrier and dual-carrier reception, as well as compressive-sampling spectrum scanning into a single architecture. With continuous-wave-modulated mixer clocks, the receiver supports concurrent reception from two distinct bands and realizes tuned impedance matching that greatly improves the OB linearity. With pseudo-noise-modulated mixer clocks, the receiver supports spectrum scanning. Disabling modulation reverts the receiver into a single-carrier receiver with good OB linearity. The 65nm CMOS prototype is developed that operates from 300 to 1300MHz and offers 2.7dB minimum NF, -1.3dBm B1dB, and +8.0dBm IIP3 for single-carrier reception. Concurrent dual-carrier reception is demonstrated that offers -8.4dBm B1dB and sub-6dB NF with the two carriers separated from 200 to 600MHz apart. For spectrum scanning, the receiver achieves a 66dB dynamic range with -75dBm sensitivity over a 630MHz RF span. In addition, a discussion of the higher-order MMC technique is included to improve the receiver’s spurious and noise performance by suppressing the higher-order responses and mitigating the noise-folding effect. Next, we present an IF-filterless, double-conversion receiver. The concurrent, narrowband RF interface is realized with two layers of passive mixing in its mixer-first branches, which translate the low-pass, baseband impedance twice to two distinct bands and improve the OB linearity. Branches with DDS-modulated LNTAs for multi-phase, switched-Gm mixing offer rejection of spurious responses and improved noise performance. The 65nm CMOS prototype is developed that operates from 100 to 1200MHz. For single-carrier reception, the receiver delivers 4.8dB minimum NF, +7.9dBm B1dB, and +22.8dBm IIP3. For concurrent signal reception, two arbitrarily-allocated RF carriers, separated from 200 to 600MHz apart, can be received concurrently. The receiver delivers a +1.9dBm B1dB and supports 8-/16-phase DDS modulation with a 30dB spurious rejection across its operating range. In addition, a theoretical study of a modified, mixer-first branch is included. By re-arranging the connections of the baseband termination resistors, the baseband noise can be fully cancelled, thus improving the receiver’s noise performance.
56

Tactile display for mobile interaction

Pasquero, Jerome. January 2008 (has links)
No description available.
57

The System Design of a Global Communications System for Military and Commercial use Utilizing High Altitude Unmanned Aerial Vehicles (UAVs) and Terrestrial Local Multipoint Distribution Service (LMDS) Sites

Banks, Bradley 12 May 2000 (has links)
This thesis proposes the design of the UAV-LMDS communication system for military and commercial use. The UAV-LMDS system is a digital, wireless communication system that provides service using unmanned aerial vehicles (UAVs) flying at 60,000 ft. acting as communication hubs. This thesis provides background information on UAV-LMDS system elements, a financial analysis, theory, link budgets, system component design and implementation issues. To begin the design, we develop link budgets that are used to characterize system parameters. We present detailed antenna designs for the antennas aboard the UAV. We also present communication equipment block diagrams. Included are technical details on military and commercial geostationary satellites used to link transmissions in the system. Implementation issues in the military system are discussed. Mobility and the effects of vegetation in the propagation path are investigated and a co-channel interference study is done. This thesis shows that by using UAVs and LMDS, a viable, broadband, wireless communications system can be created for military and commercial use. / Master of Science
58

A systems engineering process to evaluate and enhance the disaster communication capabilities of the American Red Cross

McGovern, Mark J. 05 September 2009 (has links)
This project developed a process for developing and evaluating enhancements to the American Red Cross’ disaster communication system. The stimulus for this project was a statement from the American Red Cross Disaster Service staff that the present communication system was unable to meet their needs. Some proposals for altering the present system were available, but there was no established means to identify the merits and drawbacks of these proposals. A principal feature of the proposed development process is a methodology to evaluate the impact, benefit, and cost of proposed enhancements. This methodology can be used to evaluate any proposed change to the disaster communication system. The process and methodology which have been developed are adaptations of accepted systems engineering tools such as the Life Cycle, mission scenarios, and models. / Master of Science
59

Configurable Architecture for System-Level Prototyping of High-Speed Embedded Wireless Communication Systems

Subramanian, Visvanathan 02 October 2003 (has links)
Broadband wireless technologies have the potential to provide integrated data and multimedia services in several niche areas. There is a growing need to develop high-performance communication systems that can satisfy high-end data processing requirements inherent in these technologies. The speed and complexity of these systems necessitates designers to break away from traditional architectures and design methodologies. A more comprehensive and demanding design and verification process including both hardware and software is required. Field-programmable gate arrays (FPGA) offer an attractive alternative to the low efficiency of Digital Signal Processor (DSP) based systems and low flexibility of Application Specific Integrated Circuits(ASIC). The availability of high-density, high-performance field-programmable gate arrays with several capabilities, like embedded memory and advanced routing, together with the adaptability that they offer make them highly desirable for developing hardware prototypes of communication systems. This thesis describes the development of a configurable architecture and FPGA-based design methodology used in the development of a Local Multipoint Distribution Service (LMDS) gateway for a disaster response network. The design of the gateway posed several challenges due to high data rates (120 Mbits/sec) and adaptive features like variable Forward Error Correction Coding and optional link-level retransmissions. The design decisions and simulation results of the verification process are discussed in detail. Finally, the aspects of testing and integration of the prototype in the overall system are discussed. / Master of Science
60

An inclusive design perspective on communication barriers in healthcare for ethnic minority consumers

Taylor, Shena Parthab January 2012 (has links)
This thesis contributes original knowledge through an inclusive design approach to lowering language and communication barriers in healthcare and suggests shifting the discussion from culture to context to lower intra-cultural hindrances towards learning English amongst some ethnic minorities. It offers an adaptable, scalable concept for gathering data on ethnic minorities (considering both different generations and religions) and employs a framework based analysis in design. Over the course of three studies grounded on theoretical insights from literature, primary research lead to the development and testing of innovative aids for communication, including educative and motivational elements. This research began by seeking to understand ethnic minority consumers (EMCs) perceptions of any barriers hindering their take-up of products or services in the UK, and their preferences. This is particularly significant as the UK s EMC population is predicted to double by 2051 and to diversify further, presenting challenges for social cohesion and planning future community goals. EMCs also represent a significant market for service and product providers. The research focussed on EMCs from the Indian Subcontinent based on religions and generations. It highlighted that first generation females lacking English and/or literacy (across religions and age groups) faced problems with services and issues around empowerment . The importance of improved access to healthcare was a strong theme. On investigating NHS staffs perceptions, five barriers were identified (Language barriers; Low-literacy; a Lack of understanding; Attitudes, gender and health beliefs; and Information retention) and that a female subgroup was particularly affected. This study sets out staffs perceptions of the aids currently employed and suggestions of what would help. It identified a (currently) low use of visual communication aids in adult-patient care and that pharmacist-patient communication in pharmacies was low. Ideally, staff would like patients to learn English and to use more low-cost visual communication aids. These findings lead to the development of innovative visual communication aids through inclusive and user-centred approaches and participatory design and brainstorming methods. This enabled the development of aids by considering the needs of NHS staff, EMCs lacking English and/or literacy and indigenous elderly people to promote better patient-staff communication including a take-away educational element for learning English at home.

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