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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.
11

Strategier, prissättning och prismodeller : En jämförelse mellan två lokala gym / Strategies, pricing and price models : A comparison between two local gyms

Ansin, Johan, Nilsson, Patrik January 2015 (has links)
Det finns få studier kring hur organisationer gör när de sätter sina priser på tjänster, därför är det aktuellt med en studie kring just detta. Samtidigt finns det alltjämt ett växande intresse och en ökad uppmärksamhet kring olika och nya hälsotrender med olika dieter och träningsformer, där allt fler väljer att bli medlemmar vid olika gymanläggningar. Därför har denna uppsats följande problemformuleringar: Vad karaktäriserar strategier och prissättningsprocesser hos lokala gym? Vilka prismodeller tillämpas och hur bidrar de till att realisera strategi och mål?   Syftet med denna uppsats är att undersöka hur lokala gym går till väga när de sätter sina priser, hur priserna i sin tur påverkar verksamheten och hur de bidrar till att realisera sina strategier. Detta genom att i denna uppsats använda oss av semistrukturerade intervjuer för att undersöka och jämföra två gym i Visby. Ett gym med ett klassiskt koncept, i det här fallet Gym1, jämförs med ett fitnesscenter, Form Visborg, som har ett modernt koncept som följer de nya trenderna med stor variation av träning och utbud.   För att svara på frågeställningarna används prismodell-equalizer, som är ett verktyg för att se vad i ett erbjudande företag tar betalt för. För att få förståelse för strategier används teorier som Porter och Mintzberg tagit fram, bland annat basstrategierna; differentiering, kostnadsledarskap och fokusering. För att sätta priser kan prissättningsmål och prissättningspolicys användas samtidigt som företagets varumärke och rykte kan påverka vilket pris ett tjänsteföretag sätter.   I analysen har det bland annat framkommit att det finns möjlighet för de båda gymmen att ändra sin prisformel för sina årskort, från att ta en fast avgift till en lägre fast avgift plus anpassa avgiften efter hur mycket kunden tränar. Detta för att gymmen då får möjlighet till att locka priskänsliga kunder samtidigt som de säkerställer en viss intäkt.   Slutsatserna vi dragit är att det mindre gymmet inte har utarbetade strategier och mål på samma sätt som det större gymmet. Vi kan även se att det som ingår i deras olika prismodeller varierar. Variationerna gäller mellan olika träningskort hos respektive gym men det finns också skillnader gymmen emellan. Vi har även kommit fram till att det finns möjlighet till att vidareutveckla prismodell-equalizern där ett reglage går från fasta steg till en glidande skala. / There are few studies on how organizations do when they set their prices for services, so it is up to date with a study of just that. Meanwhile, there is still a growing interest and increased attention to different and new health trends with different diets and exercises, where more and more choose to become members at different gym facilities. Therefore this paper asks the following questions: What characterizes strategies and pricing processes at the local gyms? Which pricing model applies and how do they contribute to the realization of the strategy and goals? The purpose of this paper is to examine how local gyms go about setting prices, how prices affect the business and how they help to realize their strategies. This, in this paper makes use of semi-structured interviews to examine and compare the two gyms in Visby. A gym with a more classic concept, in this case Gym1, compared with a fitness center, Form Visborg, which has a modern concept that follows the new trends with great variety of training and selection. To answer our questions we used pricing model equalizer, which is a tool to see what in an offer companies charge for. To get an understanding of strategies we used theories Porter and Mintzberg developed, including base strategies; differentiation, cost leadership and focus. To set prices may pricing goals and pricing policies be used while the company's brand and reputation can influence what price the service companies set. The analysis has revealed that there is an opportunity for the two gyms to change their price formula for their season tickets, from taking a fixed rate to a lower fixed fee plus customize fee based on how much the customer training. This is to gyms as an opportunity to attract price-sensitive customers while ensuring certain revenue. The conclusions we have drawn is that the smaller gym have not developed strategies and goals in the same way as the larger gym. We can also see that what’s included in their various pricing models vary. The variation applies between their different training cards of the respective gym but there are also differences between the gyms. We have also come to the conclusion that there is an opportunity to further develop price model equalizer in which a slider goes from solid steps to a sliding scale.
12

A Simple Adaptive FSK Modem

Tiernay, Robert 05 1900 (has links)
<p> A simple and relatively inexpensive equalizer has been developed in conjuction with a FSK modulator and demodulator (modem) for the transmission of digital data over time dispersive channels. </p> <p> The transmitter structure consists of a digital modulator followed by two filters, the first of which is a binary transversal filter (BTF), the second a conventional two-stage R-C low-pass filter. </p> <p> In the receiver structure a phaselock loop (PLL) is employed as a discriminator. Synchronization is achieved with a digital phaselock loop (DPLL). Considerable attention is placed on the error rate optimization of the receiving structure. </p> <p> The equalizer uses binary transversal filter comprising a tapped delay line, realized by a long string of metal-oxide semiconductor (MOS) flipflops, with a variable gain circuit associated with each tap in the delay line. The operation of the equalizer is adaptive in that the tap gains are adjusted rom the received data, consequently the tap gains are continually optimized. The algorithm employed for setting the tap gains is simple and can be quite easily implemented using a combination of analog and digital techniques. </p> <p> Experimental results are presented which illustrate the important features of the system implemented under a variety of operating conditions. </p> / Thesis / Master of Engineering (MEngr)
13

A general broadband matching theory and its application

Tsai, Cheng-Kwang January 1981 (has links)
No description available.
14

Multipath Channel Considerations in Aeronautical Telemetry

Gagakuma, Edem Coffie 01 May 2017 (has links)
This thesis describes the use of scattering functions to characterize time-varying multipath radio channels. Channel Impulse responses were measured at Edwards Air Force Base (EAFB) and scattering functions generated from the impulse response data. From the scattering functions we compute the corresponding Doppler power spectrum and multipath intensity profile. These functions completely characterize the signal delay and the time varying nature of the channel in question and are used by systems engineers to design reliable communications links. We observe from our results that flight paths with ample reflectors exhibit significant multipath events. We also examine the bit error rate (BER) performance of a reduced-complexity equalizer for a truncated version of the pulse amplitude modulation (PAM) representation of SOQPSK-TG in a multipath channel. Since this reduced-complexity equalizer is based on the maximum likelihood (ML) principle, we expect it to perform optimally than any of the filter-based equalizers used in estimating received SOQPSK-TG symbols. As such we present a comparison between this ML detector and a minimum mean square error (MMSE) equalizer for the same example channel. The example channel used was motivated by the statistical channel characterizations described in thisthesis. Our analysis shows that the ML equalizer outperforms the MMSE equalizer in estimating received SOQPSK-TG symbols.
15

Adaptive Third-Order Volterra Satellite Channel Equalizer

Lin, Wen-Hsin 17 July 2001 (has links)
Digital satellite communication systems are equipped with nonlinear amplifiers such as travelling wave tube (TWT) amplifiers at or near saturation for better efficiency. The TWT exhibits nonlinear distortion in both amplitude and phase (AM/AM and AM/PM) conversion, respectively. That is, in the digital satellite communication the transmission is disturbed not only by the non-linearity of transmitter amplifier, but also by the inter-symbol interference (ISI) with additive white Gaussian noise. To compensate the non-linearity of the transmitter amplifier and ISI, in this thesis, a new nonlinear compensation scheme consists of the predistorter and adaptive third-order Volterra-based equalizer, with the inverse QRD-RLS (IQRD-RLS) algorithm, which are located before and after the nonlinear channel, is proposed respectively. The third-order Volterra filter (TVF) equalizer based on the IQRD-RLS algorithm achieve superior performance, in terms of convergence rate, steady-state mean-squared error (MSE), and numerically stable. They are highly amenable to parallel implementation using array architectures, such as systolic arrays. The computer simulation results using the M-ary PSK modulation scheme are carried out the signal¡¦s constellation diagrams, the learning curve of the MSE and the bit error rate (BER) are compared with conventional least mean square (LMS), gradient adaptive lattice (GAL) and adaptive LMS with lattice pre-filter algorithms.
16

Eye opening monitor for optimized self-adaptation of low-power equalizers in multi-gigabit serial links

Narayanan, Anand January 2013 (has links)
In modern day communication systems, there is a constant demand for increase in transmission rates. This is however limited by the bandwidth limitation of the channel. Inter symbol interference (ISI) imposes a great threat to increasing data rates by degrading the signal quality. Equalizers are used at the receiver to compensate for the losses in the channel and thereby greatly mitigate ISI. Further, an adaptive equalizer is desired which can be used over a channel whose response is unknown or is time-varying. A low power equalizing solution in a moderately attenuated channel is an analog peaking filter which boosts the signal high frequency components. Such conventional continuous time linear equalizers (CTLE) provide a single degree of controllability over the high frequency boost. A more complex CTLE has been designed which has two degrees of freedom by controlling the high frequency boost as well as the range of frequencies over which the boost is applied. This extra degree of controllability over the equalizer response is desired to better adapt to the varying channel response and result in an equalized signal with a wider eye opening. A robust adaptation technique is necessary to tune the equalizer characteristics. Some of the commonly used techniques for adaptation of CTLEs are based on energy comparison criterion in the frequency domain. But the adaptation achieved using these techniques might not be optimal especially for an equalizer with two degrees of controllability. In such cases an eye opening monitor (EOM) could be used which evaluates the actual signal quality in time domain. The EOM gives an estimate on the signal quality by measuring the eye opening of the equalized signal in horizontal and vertical domain. In this thesis work a CTLE with two degrees of freedom with an EOM based adaptation system has been implemented.
17

An Efficient FPGA Implementation of a Constant Modulus Algorithm Equalizer for Wireless Telemetry

Schumacher, Robert G., Jr. January 2014 (has links)
No description available.
18

ELECTRICAL EQUALIZATION FOR MULTIMODE FIBER SYSTEMS

Liu, Yizhou 11 January 2017 (has links)
No description available.
19

VITERBI AND SERIAL DEMODULATORS FOR PRE-CODED BINARY GMSK

Lui, Gee L., Tsai, Kuang 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Three different demodulators applicable to the coherent demodulation of binary Gaussian Minimum Shift Keying (GMSK) signal are described and their performance compared. These include a near-optimal trellis demodulator, which utilizes two matched filters and Viterbi algorithm to carry out maximum likelihood sequence estimation, and a singlefilter threshold demodulator with and without pulse equalization. The performance of these demodulators in noise and adjacent channel interference (ACI) are compared for several signal BT products. The equalized threshold demodulator is shown to perform nearly as well as the near-optimal trellis demodulator in additive white Gaussian noise (AWGN), and substantially outperform the trellis demodulator under severe ACI condition.
20

FPGAs: RE-INVENTING THE SIGNAL PROCESSOR

Dick, Chris 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / FPGAs are increasingly being employed for building real-time signal processing systems. They have been used extensively for implementing the PHY in software radio architectures. This paper provides a technology and market perspective on the use FPGAs for signal processing and demonstrates FPGA DSP using an adaptive channel equalizer case study.

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