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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.
761

Challenges in fuzzy front end of new product development within medium-sized enterprises : A case study on Swedish manufacturing firms

Korityak, Agnesa, Cao, Yue January 2010 (has links)
The business environment is changing rapidly, becoming very competitive and challenging for all firms, and particularly for small and medium enterprises (SMEs). As innovation and new product development represent valuable sources for SMEs’ future sustainability and development, making these processes more effective is essential. Previous literature, with the focus on large firms, underlined the importance of efficiently managing the early period of new product development (NPD), as this can reduce the product’s time to market and increase its performance. For this reason, contributing to a developed understanding of the challenges of medium-sized firms in managing this phase, the fuzzy front-end (FFE) of NPD, is the aim of this study. The theoretical framework of this study combines prior theories that relate to the difficulties, shortcomings, challenges that SMEs meet during the whole NPD process, including FFE, and theories that resulted from research on FFE in large firms. The structure is based on four elements referring to managing the idea generation process, new product development team, evaluation of product concept feasibility, and the organization of FFE. A qualitative strategy and a research design with two case studies on high-tech, medium-sized manufacturing firms were used in reaching the purpose of this study. This methodology choice reflects the explorative purpose of this research. The empirical data are mainly primary data, collected during three interviews with development managers and a product developer, completed as well with secondary data like general company information, collected from companies’ websites. The analysis of empirical findings revealed some relevant conclusions, which can bring value to the research area, and also to the practice. Our findings show that lack of communication with customers during the whole FFE phase, collecting limited or inaccurate information to be processed during this phase, finding the right formalization degree of FFE activities, determining the complexity of the product concept, and assessing external technology and expertise, represent the main challenges faced by medium-sized firms in the FFE of NPD. The study’s practical relevance consists in the advices and solutions suggested to managers for overcoming the challenges of the FFE phase and improving their results in the development projects. The theoretical implications reflect the importance of organizational size variable in association with the challenges of FFE. The sample of only two cases and the quality of the empirical data collected from two high-tech Swedish manufacturing firms which have a large focus on innovation are the main limitations of this study, as these medium-sized firms have gained some experience to face the specific challenges of FFE of NPD and the data they provide may be influenced by this aspect.
762

Separate Hydrolysis and Fermentation of Pretreated Spruce

Axelsson, Josefin January 2011 (has links)
Bioethanol from lignocellulose is expected to be the most likely fuel alternative in the near future. SEKAB E-Technology in Örnsköldsvik, Sweden develops the technology of the 2nd generation ethanol production; to produce ethanol from lignocellulosic raw material. The objective of this master’s thesis was to achieve a better knowledge of the potential and limitations of separate hydrolysis and fermentation (SHF) as a process concept for the 2nd generation ethanol production. The effects of enzyme concentration, temperature and pH on the glucose concentration in the enzymatic hydrolysis were investigated for pretreated spruce at 10% DM using a multiple factor design. Enzyme concentration and temperature showed significant effects on the glucose concentration, while pH had no significant effect on the concentration in the tested interval of pH 4.5-5.5. To obtain the maximum glucose concentration (46.4 g/l) for a residence time of 48 h, the optimal settings within the studied parameter window are a temperature of 45.7⁰C and enzyme concentration of 15 FPU/g substrate. However, a higher enzyme concentration would probably further increase the glucose concentration. If enzymatic hydrolysis should be performed for very short residence times, e.g. 6 h, the temperature should be 48.1⁰C to obtain maximum glucose concentration. The efficiency of the enzymes was inhibited when additional glucose was supplied to the slurry prior to enzymatic hydrolysis. It could be concluded that end product inhibition by glucose occurs and results in a distinct decrease in glucose conversion. No clear conclusions could be drawn according to different techniques for slurry and enzymes, i.e. batch and fed-batch, in the enzymatic hydrolysis process. Investigations of the fermentability of the hydrolysate revealed that the fermentation step in SHF is problematic. Inhibition of the yeast decrease the fermentation efficiency and it is therefore difficult to achieve the 4% ethanol limit. Residence time for enzymatic hydrolysis (48 h) and fermentation (24 h) need to be prolonged to achieve a sufficient SHF process. However, short processing times are a key parameter to an economically viable industrial process and to prolong the residence times should therefore not be seen as a desirable alternative. SHF as a process alternative in an industrial bioethanol plant has both potential and limitations. The main advantage is the possibility to separately optimize the process steps, especially to be able to run the enzymatic hydrolysis at an optimal temperature. Although, it is important to include all the process steps in the optimization work. The fermentation difficulties together with the end product inhibition are two limitations of the SHF process that have to be improved before SHF is a preferable alternative in a large scale bioethanol plant.
763

Design and Implementation of a high-efficiency low-power analog-to-digital converter for high-speed transceivers

Younis, Choudhry Jabbar January 2012 (has links)
Modern communication systems require higher data rates which have increased thedemand for high speed transceivers. For a system to work efficiently, all blocks ofthat system should be fast. It can be seen that analog interfaces are the main bottleneckin whole system in terms of speed and power. This fact has led researchersto develop high speed analog to digital converters (ADCs) with low power consumption.Among all the ADCs, flash ADC is the best choice for faster data conversion becauseof its parallel structure. This thesis work describes the design of such a highspeed and low power flash ADC for analog front end (AFE) of a transceiver. Ahigh speed highly linear track and hold (TnH) circuit is needed in front of ADCwhich gives a stable signal at the input of ADC for accurate conversion. Twodifferent track and hold architectures are implemented, one is bootstrap TnH andother is switched source follower TnH. Simulations show that high speed with highlinearity can be achieved from bootstrap TnH circuit which is selected for the ADCdesign.Averaging technique is employed in the preamplifier array of ADC to reduce thestatic offsets of preamplifiers. The averaging technique can be made more efficientby using the smaller number of amplifiers. This can be done by using the interpolationtechnique which reduces the number of amplifiers at the input of ADC. Thereduced number of amplifiers is also advantageous for getting higher bandwidthsince the input capacitance at the first stage of preamplifier array is reduced.The flash ADC is designed and implemented in 150 nm CMOS technology for thesampling rate of 1.6 GSamples/sec. The bootstrap TnH consumes power of 27.95mW from a 1.8 V supply and achieves the signal to noise and distortion ratio(SNDR) of 37.38 dB for an input signal frequency of 195.3 MHz. The ADC withideal TnH and comparator consumes power of 78.2 mW and achieves 4.8 effectivenumber of bits (ENOB).
764

Connected Me : Hardware for high speed BCC

Babu, Bibin January 2012 (has links)
Body coupled communication (BCC) is a hot topic in personal networking domain. Many works arepublished suggesting different architectures for BCC since its inception in 1995 by Zimmerman. The number ofelectronic gadgets used by a single person increases as time pass by. Its a tedious job to transfer data betweenthen from a user point of view. Many of these gadgets can share their resources and save power and money.The existing wired or wireless networks does not meet the requirements for this network like scalable data rate,security etc. So here comes the novel idea of using human body as communication medium. The aim of thisthesis is to realize a hardware for BCC based on wide band signaling as part of a big project.The human body consists of 70% of water. This property makes the human body a fairly good conductor.By exploiting this basic property makes the BCC possible. A capacitance is formed if we place a metal platenear to the human body with the skin as a dielectric. This capacitance forms the interface between the humanbody and the analog front-end of the BCC transceiver. Any other metal structures near to the human body canattenuate the signal.A first-order communication link is established in software by the human body model and the transceiver inthe loop along with noise and interference. This communication link is used to verify the human body modeland the base band model done as part of the same big project. Based on the results a hardware prototype isimplemented. Measurements are taken in different scenarios using the hardware setup. The trade-off betweendesign parameters are discussed based on the results. At the end, it suggests a road map to take the projectfurther.
765

Bedömning av kommersiell potential vid produktutveckling : - Att anpassa marknadsanalys och produktutvecklingsprocess efter idéns förutsättningar

Östlund, Fredrik, Brännlund, Henrik January 2011 (has links)
No description available.
766

Multimedia and Purchase Intentions : Web Design for Fashion E-Tailers

Carlsson, Lisa J., Chehimi, Sara January 2011 (has links)
Recently, many high-end fashion designers have established their own e-commerce site. However, due to the difficulties of replicating the brick and mortar environment and the increase of competition, it has become more difficult to convert visitors into buyers. In order to attract buyers, some retailers add a lot of multimedia content. The purpose of this thesis is to investigate attitude towards multimedia and whether it influences one’s online purchasing intentions for high-end fashion.
767

De sista samtalen bortom orden : Sjuksköterskors upplevelse av vårdens stöd till livets slut / The last talks beyond words : Nurses' experience of healthcare support to end of life

Munk, Lykke January 2012 (has links)
Inledning: För att få så god mänsklig omsorg som möjligt i livets slutskede behöverpatienter ha någon att dela den sista svåra tiden med. Syftet med undersökningen var att försöka förstå hur övergången mellan liv och död kan underlättas. Frågeställning: Studien avsåg att besvara fyra frågeställningar. – Förutsättningar för samtalet med den döende vid livets slutskede? – Är det genomförbart att vårda människor med värdighet till livets slut? – Går det att skapa emotionella band och känslomässig närhet till patienter som befinner sig vid livets slutskede? – Hur kan vården stödja den döende med hjälp av kultur, musik, konst? Metod: En kvalitativ undersökning valdes. Intervjuer gjordes med fem legitimerade sjuksköterskor som arbetade på Hospice. Resultatet visade att dialogen är utgångspunkten för det mellanmänskliga äkta mötet. Trots kroppens förfall finns förutsättningar att vårda patienten med värdighet till livets slut. Det uppstår emotionella band mellan patienterna och de legitimerade sjuksköterskorna som varar till livet slut. Konst, musik, litteratur och andlighet är betydelsefullt för patienternas förmåga att uthärda det svåra lidandet. På Hospice bejakas livet och döden betraktas som en normal process. Slutsatser: De legitimerade sjuksköterskorna uppvisade en hög samstämmighet i sina svar och en gemensam vård filosofi, där samtalet var en viktig länk inom den palliativa vården. Det ar höga ideal om en värdig död och arbetar hårt för att främja detta mål. Samstämmigheten kan beror på ett urval av sjuksköterskor med stort engagemang, känsla för mening och syfte med sitt arbete samt personlig inre mognad. Den palliativa vårdens filosofi kan fördjupas genom fortsatt forskning och utveckling, vilket skulle kunna leda till en egen specialitet, Palliativ Medicin.
768

Design and simulation of beam steering for 1D and 2D phased antenna arrays using ADS.

Afridi, Muhammad Zeeshan, Umer, Muhammad, Razi, Daniyal January 2012 (has links)
Phased arrays eliminate the problems of mechanical steering by using fast and reliable electronic components for steering the main beam. Modeling and simulation of beam steering for 1D and 2D arrays is the aspect that is considered in this thesis. A 1D array with 4 elements and a 2D array with 16 elements are studied in the X-band (8-12 GHz). The RF front-end of a phased array radar is modeled by means of ADS Momentum (Advanced design system).
769

Design of CMOS RF-Switches for a Multi-Band Radio Front-End / Design av CMOS RF-switchar för sändar- och mottagardel i en flerbandsradio

Hedberg, Anders January 2003 (has links)
A study has been made in CMOS RF-switches that can be used in the front-end of a multi-band radio targeting the 802.11a,b,g and W-CDMA standards and working in the frequency range 2.4-5.5GHz. Especially, one single-transistor switch and two types of transmission gates have been analyzed, simulated and compared with respect to loss, linearity, compression point and noise. From this, five different single-transistor switches have been designed for on-chip probing measurements. Special consideration has been taken to accommodate on-chip testing, thus additional structures have been designed. The simulations and design has been performed with Chartered 0.18um RF-CMOS process. The results from the simulations show that the single-transistor switch has better performance in loss, linearity, compression point and noise compared to the transmission gates. However, for the transmission gates the linearity can be increased beyond the linearity of the single-transistor switch if the widths of the transistors are made sufficiently large. For the single-transistor switch, simulation results show that the transistor length shall be kept to its minimum for best performance and that the number of fingers does not influence significantly. Also, there are optimum values for the loss in on-mode, the noise and the linearity and worst-case values for the loss in off-mode when the transistor width is varied. Consequently, the single- transistor switch can be tuned by its transistor width to accommodate desired performances.
770

RF transceiver front-end design for testability

Li, Lin January 2004 (has links)
In this thesis, we analyze the performance of a loop-back built-in-self-test for a RF transceiver front-end. The tests aim at spot defects in a transceiver front-end and they make use of RF specifications such as NF (Noise Figure), G (power gain) and IIP3 (third order Intercept point). To enhance fault detectability, RF signal path sensitization is introduced. We use a functional RF transceiver model that is implemented in MatLab™ to verify this analysis.

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