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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.
111

Mild Wet Torrefaction and Characterization of Woody Biomass from Mozambique for Thermal Applications

Cuvilas, Carlos Alberto January 2015 (has links)
Mozambique has vast forestry resources and also considerable biomass waste material such as bagasse, rice husks, sawdust, coconut husks and shells, cashew nut shell and lump charcoal waste. The potential of the total residues from the agricultural sector and the forest industry is estimated to be approximately 13 PJ. This amount of energy covers totally the production of charcoal which amounted to approximately 12.7 PJ in 2006. Although biomass is an attractive renewable source of energy, it is generally difficult to handle, transport, storage and use due to its lower homogeneity, its lower energy density and the presence of non-combustible inorganic constituents, which leads to different problems in energy conversion units such as deposition, sintering, agglomeration, fouling and corrosion. Therefore, a pretreatment of the biomass to solve these problems could lead to a change of current biomass utilization situation. The aim of this study is to convert Mozambican woody biomass residue into a solid biochar that resembles low-grade coal. In this work the current energy situation in Mozambique has been reviewed, and the available and potential renewable sources including residues from agricultural crops and forest industry as energy have been assessed. It was found that the country is endowed with great potential for biofuel, solar, hydro and wind energy production. However, the production today is still far from fulfilling the energy needs of the country, and the majority of people are still not benefiting from these resources. Charcoal and firewood are still the main sources of energy and will continue to play a very important role in the near future. Additionally, enormous amounts of energy resources are wasted, especially in the agricultural sector. These residues are not visible on national energy statistics. The chemical composition and the fuelwood value index (FVI) showed that by failing to efficiently utilise residues from Afzelia quanzensis, Millettia stuhlmannii and Pterocarpus angolensis, an opportunity to reduce some of the energy related problems is missed. An evaluation of effect of a mild wet torrefaction pretreatment showed that the chemical composition of the biochar is substantially different than the feedstock. The use of diluted acid as catalysts improves the biochar quality, namely in terms of the energy density and ash characteristics; however, the increment of the S content in the final product should be considered for market acceptance (because the fuels have a maximum allowance for S concentration). The thermal behaviour of the untreated and treated biomass was also investigated. The pyrolytic products of umbila and spruce were affected by the treatment and catalyst in terms of yield and composition of the vapours. / <p>QC 20150202</p>
112

Optimization and design of a detection system based on transmission tomography with fast neutrons

Bjelkenstedt, Tom January 2014 (has links)
This thesis is part of a project focusedon investigating the possibility ofmeasuring void distributions usingtransmission tomography with fastneutrons. The measurements are plannedto be conducted at thermal hydraulictest loops. The project, called STUNT,is carried out at Uppsala University atthe division for applied nuclearphysics.The purpose of this work was to designand optimize a detection system for thedetection of fast neutrons in the abovementioned environment. For this purpose,detector elements consisting of theplastic scintillator material EJ208 wasmodeled using the particle transportcode MCNPX.Both plate shaped elements and fibers ofdifferent dimensions where tested forperformance.Through a comparison utilizing severalfigures of merit and MATLAB, the plateshape was selected with an element widthof 2.6 mm. During the optimizationprocess a possible detector design with73 detector plates was chosen. At anenergy threshold of 11 MeV the followingdesign parameters were found; adetection efficiency of 3.0 %, a signalto background ratio of 15, a totalmeasurement time of 3600 s and a pixelresolution of 1.4 mm.A point spread function was produced andtwo projection tests where conductedusing a water filled steel cylinder asobject. / STUNT
113

Belöningssystem - En studie om butikssäljares preferens av belöningssystem

Nemati, Mona, Jakobsson, Sofie January 2014 (has links)
Titel:                     Belöningssystem - En studie om butikssäljares preferens av belöningssystem  Problem:             Belöningssystem, vilket inkluderar lön, är ett styrmedel som uppmuntrar anställdas beteende och utförda arbetsinsatser. Vid utformande av belöningssystem ställs företag inför komplicerade frågor där de måste ta hänsyn till just deras anställda och verksamhetens unika situation. Det finns olika variabler som påverkar en anställds preferens för ett visst belöningssystem. Utan hänsyn till dessa variabler finns en risk att företag tillämpar ett belöningssystem som inte ger maximal nytta.  Syfte:                    Ambitionen med denna studie är att beskriva butikssäljares inställning till fast- respektive provisionsbaserat belöningssystem samt om personliga variabler påverkar butikssäljares preferens av ett visst belöningssystem.  Metod:                 I studien har författarna tillämpat en kvantitativ ansats. För insamling av data utformades en enkät med bundna svarsalternativ vilken grundat det empiriska material som krävts för att genomföra studien. Bearbetning av insamlad data har gjorts med statistikprogrammet IBM SPSS Statistics 21.0 som analysverktyg.  Slutsats:              Genom studien har det påvisats att preferens för ett visst belöningssystem har samband med personliga variabler. Butikssäljare med känslan av att kunna påverka kundens köpval i butik samt de som anser att nuvarande lön inte är representativ för presterad arbetsinsats visar preferens för ett delvis provisionsbaserat belöningssystem. / Title:                                               Reward Systems - A study of sales assistants’ views on reward systems  Problem:             Reward system, which includes salary, is a management tool that encourages employee behaviour and work performance. When implementing a reward system companies face issues where they have to be attentive to their specific employees and the company’s unique situation. There are different variables that affect an employee’s preference for a certain reward system. Without knowledge of these variables there is a risk that companies applies a reward system that does not provide maximum benefit.  Purpose:             The purpose of this study is to describe sales assistants view on salary and merit pay and if personal variables affect the sales assistant’s preference of a certain reward system.  Method:              In this study the authors applied a quantitative method. For the collection of data a questionnaire with closed response options was designed to give the authors the empirical data required to conduct this study. Processing of the data collected has been analysed through the statistic data programme IBM SPSS Statistics 21.0.  Conclusion:       This study presented that an employee’s preference for a reward system is linked to personal variables. Sales assistants who feel they can influence a customers purchase choice, and those who think their current salary do not represent work performance show preference for a merit pay reward system.
114

Fast prime field arithmetic using novel large integer representation

Alhazmi, Bader Hammad 10 July 2019 (has links)
Large integers are used in several key areas such as RSA (Rivest-Shamir-Adleman) public-key cryptographic system and elliptic curve public-key cryptographic system. To achieve higher levels of security requires larger key size and this becomes a limiting factor in prime finite field GF(p) arithmetic using large integers because operations on large integers suffer from the long carry propagation problem. Large integer representation has direct impact on the efficiency of the calculations and the hardware and software implementations. Attempts to use different representations such as residue number systems suffer from their own problems. In this dissertation, we propose a novel and efficient attribute-based large integer representation scheme capable of efficiently representing the large integers that are commonly used in cryptography such as the five NIST primes and the Pierpont primes used in supersingular isogeny Diffie-Hellman (SIDH) used in post-quantum cryptography. Moreover, we propose algorithms for this new representation to perform arithmetic operations such as conversions from and to binary representation, two’s complement, left-shift, numbers comparison, addition/subtraction, modular addition/subtraction, modular reduction, multiplication, and modular multiplication. Extensive numerical simulations and software implementations are done to verify the performance of the new number representation. Results show that the attribute-based large integer arithmetic operations are done faster in our proposed representation when compared with binary and residue number representations. This makes the proposed representation suitable for cryptographic applications on embedded systems and IoT devices with limited resources for better security level. / Graduate / 2020-07-04
115

Foreign fast food chains in the People's Republic of China.

January 1994 (has links)
by Tam Yuen-chiu, Stephen. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 50-52). / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / TABLE OF CONTENTS --- p.iv / LIST OF TABLES --- p.vi / CHAPTER / Chapter I. --- INTRODUCTION --- p.1 / Objectives --- p.2 / Chapter II. --- METHODOLOGY --- p.3 / Secondary Research --- p.3 / Primary Research --- p.4 / Definition --- p.6 / Limitations --- p.8 / Chapter III. --- THE FAST FOOD INDUSTRY IN HONG KONG --- p.9 / Fast Food Industry Background --- p.9 / Hong Kong Fast Food Chains With China Operations --- p.13 / Hong Kong Fast Food Chains Without China Operations --- p.17 / Chapter IV. --- FOREIGN FAST FOOD CHAINS IN CHINA --- p.18 / An Overview of the Retail Market Environment in China --- p.18 / Historical Development and Present Situation of Foreign Fast Food Chains --- p.20 / Chapter V. --- SUMMARY OF IN-DEPTH INTERVIEWS --- p.26 / Importance of China Business --- p.26 / Entry Motives --- p.29 / Forms of Entry --- p.30 / Problems Encountered --- p.32 / Attitude Toward Political Risks of the Tiananmen Incident --- p.36 / Competitive Advantage of Foreign Fast Food Chains in China --- p.38 / Business Results to Date Measured Against Expectations --- p.39 / Major Improvements Expected by Foreign Fast Food Chains --- p.40 / Chapter VI. --- CONCLUSIONS --- p.42 / APPENDICES --- p.43 / BIBLIOGRAPHY --- p.50
116

Positioning of fast food shops in Hong Kong: a case study on Wendy Foods Limited.

January 1992 (has links)
by Ho Lik-Shing, Adolphus and Wong Hon-Shing, Cary. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 85-86). / ABSTRACT --- p.ii / TABLE OF CONTENTS --- p.iii / LIST OF FIGURES --- p.vii / LIST OF TABLES …… --- p.viii / ACKNOWLEDGMENT --- p.ix / Chapter / Chapter I. --- INTRODUCTION --- p.1 / Project Objective --- p.2 / Methodology --- p.3 / Chapter II. --- LITERATURE REVIEW --- p.3 / Positioning --- p.3 / Importance of Positioning --- p.3 / Positioning Task --- p.5 / Identifying Possible Competitive Advantages --- p.5 / Selecting the Right Advantages --- p.6 / Effectively signalling to the market the firm's position --- p.6 / Formulation of Positioning Strategy for Wend's Food --- p.6 / Chapter III. --- INDUSTRIAL ANALYSIS OF FAST FOOD INDUSTRY IN HONG KONG --- p.8 / Restaurant Industry --- p.8 / Fast Food Industry --- p.11 / Demographic Trends --- p.14 / Geographic Trend --- p.14 / Income Trend --- p.15 / Household Size --- p.16 / Age Trend --- p.17 / Household Expenditure Pattern --- p.18 / Implications --- p.18 / Chapter IV. --- COMPETITOR ANALYSIS --- p.20 / Overview --- p.20 / Cafe-De-Coral --- p.23 / History --- p.23 / Business Strategy --- p.23 / Marketing Strategy --- p.24 / Operations Strategy --- p.25 / McDonald --- p.27 / History --- p.27 / Business Strategy --- p.27 / Marketing Strategy --- p.28 / Operations Strategy --- p.28 / Fairwood --- p.29 / History --- p.29 / Business Strategy --- p.29 / Marketing Strategy --- p.30 / Operations Strategy --- p.31 / Maxim's --- p.32 / History --- p.32 / Business Strategy --- p.32 / Marketing Strategy --- p.33 / Operations Strategy --- p.33 / Kentucky Fried Chicken --- p.34 / History --- p.34 / Business Strategy --- p.34 / Marketing Strategy --- p.34 / Operations Strategy --- p.35 / Wendy's --- p.36 / History --- p.36 / Business Strategy --- p.36 / Marketing Strategy --- p.36 / Operations Strategy --- p.38 / Comparison of Various Competitors --- p.39 / Cafe de Coral --- p.39 / McDonald --- p.39 / Fairwood --- p.40 / Maxim's --- p.40 / Kentucky Fried Chicken --- p.41 / Wendy's --- p.41 / Implications --- p.41 / Chapter V. --- RESEARCH DESIGN --- p.42 / Objectives --- p.42 / Research Methodology --- p.42 / Focus Group Study --- p.43 / Descriptions --- p.43 / Findings --- p.44 / """Questionnaire on fast food shops"" Survey" --- p.45 / Descriptions --- p.45 / """Questionnaire on Wendy's"" Survey" --- p.46 / Descriptions --- p.46 / Chapter VI. --- FINDINGS AND ANALYSIS --- p.48 / """Questionnaire on fast food shops"" Survey" --- p.48 / Findings --- p.48 / Analysis --- p.51 / """Questionnaire on Wendy's"" Survey" --- p.53 / Findings --- p.53 / Analysis --- p.55 / Discussions with Crew Members and Customers --- p.56 / About the Shop --- p.56 / About the Menu --- p.56 / About the Food --- p.57 / Implications --- p.57 / Chapter VII. --- RECOMMENDATIONS FOR WENDY'S --- p.58 / Position --- p.58 / Target Customer --- p.59 / Pricing --- p.60 / Distribution --- p.60 / Advertising --- p.61 / Areas for Improvement --- p.61 / Chapter VIII. --- LIMITATIONS AND SUGGESTIONS --- p.62 / Limitations for the Study --- p.62 / Suggestions for Further Research --- p.63 / APPENDIX --- p.64 / Chapter 1 --- Questionnaire on fast food shops --- p.64 / Chapter 2 --- "Data of ""Questionnaire on fast food shops""" --- p.70 / Chapter 3 --- Questionnaire on Wendy's --- p.75 / Chapter 4 --- "Data of ""Questionnaire on Wendy's""" --- p.79 / Chapter 5 --- Test on Different Samples --- p.83 / BIBLIOGRAPHY --- p.85
117

Fast Fashion : Företagens miljöarbete ur kundens perspektiv

WIMBY, FANNY, WALLIN, EMMA January 2013 (has links)
I samma takt som produktionen av kläder tilltar, ökar även medvetenheten kring dess miljöpåverkan. Många företag arbetar efter avtal, märkningar och uppförandekoder för att på så vis reducera påverkan, dock kan det vara svårt för konsumenterna att veta vad de faktiskt står för och betyder. Syftet med den här uppsatsen är att undersöka hur kunden ser på fast fashion-företagets miljöarbete, hur företaget själva ser på det, samt om kundens uppfattning går att förändra. Undersökningen är avgränsad till att undersöka företaget Gina Tricot som ett exempel på företeelsen fast fashion- företag. För att kunna analysera informationen används kommunikationsmodellen, där sändaren skickar ett meddelande genom bruset till mottagaren, för att senare få tillbaka feedback från mottagagaren. Den emiriska delen av arbetet består av en intervju, en enkätundersökning samt två dolda observationer. Intervjun genomfördes via mejl med Gina Tricots Hållbarhetschef Marcus Bergman. Enkätundersökningen består av ett flertal frågor kring Gina Tricots miljöarbete samt en informationstext om det här. Den dolda observationen genomfördes i två geografiskt olika butiker, där vi undersökte hur företagets miljöarbete kommuniceras i butiken. Av den insamlade informationen kan man se att kundens och företagets uppfattning om hur de arbetar med miljö skiljer sig åt. Skillnaderna kan bero på olika saker, men främst på brist i företagets kommunikation med sina kunder. / Program: Butikschef, textil och mode
118

A mathematical study of complex oscillatory behaviour in an excitable cell model

Baldemir, Harun January 2018 (has links)
Inner hair cells (IHCs) are the actual sensory receptors in hearing. Immature IHCs generate spontaneous calcium-dependent action potentials. Changing the characteristic of the Ca2Å signals modulates the amplitude and duration of the action potentials in these cells. These spontaneous action potential firing patterns are thought to be important for the development of the auditory system. The aim of this thesis is to gain a deeper understanding of the electrical activity and calcium signalling during development of IHCs from a mathematical point of view. A numerical bifurcation analysis is performed to delineate the relative contributions of the model parameters to the asymptotic behaviour of the model. In particular, we investigate the pattern of periodic solutions including single (normal) spiking, pseudoplateau burstings and complex solutions using two-parameter sections of the parameter space. We also demonstrate that a simplified (three-dimensional) model can generate similar dynamics as the original (four-dimensional) IHC model. This reduced model could be characterised by two fast and one slow or one fast and two slow variables depending on the parameters’ choice. Hence, the mechanisms underlying the bursting dynamics and mixed mode oscillations in the model are studied applying 1-slow/2-fast and 2-slow/1-fast analysis, respectively.
119

Evaluating Fast Track Time Analysis of Clinical Drug Trial Phases Utilizing a Quasi-Experimental Observational Study

McBride, Ali January 2007 (has links)
Class of 2007 Abstract / Objectives: In this paper we analyzed the time frame for oncology drugs that were designated as a fast track drug and the time transition from a phase II to phase III clinical trial completion. Methods In our study we utilized oncology drugs that were approved between the years of 2000-2006 (FDA.gov). We then analyzed the CDER data base that provided information to Fast Track drugs that have been approved within the time period as determined by the FDA selection criteria (21 CFR 312.81(a)). Under certain circumstances, the FCA may consider reviewing portions of a marketing application in advance of the complete New Drug Application (NDA) or Biologic License Application (BLA). We will evaluate fast track designated products which may also be eligible to participate in FDA’s Continuous Marketing Applications Pilot 1 or Pilot 2 programs. For our analysis, we specifically selected oncology drugs. In particular, we analyzed 32 drugs from the stated time period. Each fast track drug was then selected and analyzed for its clinical phase development time period based on news announcements during clinical trails. For each announcement we conducted an event study analysis through lexis Nexus with respect to the announcement of a clinical trial enrollment, clinical trials news (Phase I, II, III). Results: The results of our preliminary study show that there was a shorter time to development transition for the fast track oncology drugs. The oncology clinical phase transition from II to three on average lasted 12 months with a range of 2 - 29 months The average length of the phase development had to excludes 4 drugs due to the lack of information provided from the LexisNexis database. The current timeline for fats track drugs has shown a decrease in transition from clinical trials to the market. In the example of Spyrcel, the data from our study had to be excluded, there was a definitive difference in the time to approval process for the drug as compared to other standard review entities. The approvals for dasatinib, or Sprycel, for refractory CML was shown to move through the development to approval in one of the fastest timeframes in modern development. Since its first clinical study on in Gleevec-resistant patients, the medication was decided on entering an accelerated timeline. It took us just 25 months to bring Sprycel from first-in-human dosing to a regulatory submission. In contrast, the industry average for this cycle time is 6.4 years which is three times greater than the cycle time for Sprycel. Conclusions: The new Subpart H regulations state that post-marketing studies to confirm clinical benefit that would consist usually by "studies underway” at the time of accelerated approval, this has not always been the case and is not a requirement (Dagher R, Johnson J, Williams G et al). In conclusion, the accelerated approval program in oncology has been successful in making 18 different products available to patients for 22 different cancer treatment indications since the inception of the fast track program. From the current data and transition information, there is a comparative difference between the clinical phase transitions from phase II to Phase III clinical trials. However, this preliminary data needs to be further evaluated against the standard FDA review process from oncology drugs. Moreover, further studies will be needed to interpret whether the average length of oncology studies biases the value of our study.
120

Quality of sputum collected for Acid-Fast Bacilli (AFB) test from patients at Dr. George Mukhari Hospital, Pretotia

Iqbal, R January 2010 (has links)
Thesis (M Med.(Family Medicine))--University of Limpopo, 2010. / OBJECTIVE: In order to obtain optimal results using sputum smear microscopy for acid-fast bacilli (AFB) detection in the diagnosis of pulmonary tuberculosis (PTB), good quality sputum with an adequate volume of at least 5.0ml is required. An inadequate amount of sputum sample may result cases of active PTB being missed. This study was aimed at showing that a single sputum sample of at least 5.0ml would lower the chances of missing active PTB cases, and increase sputum smear positivity by microscopy thus enabling prompt treatment of PTB, and restricting its transmission. METHODS: An analytical cross sectional study was carried out at Dr George Mukhari Hospital in Pretoria, South Africa. Two sputum samples, one of 5.0ml and the other with 2.0ml were collected from each adult patient suspected of having active PTB. Sputum collection was supervised and patients were given instructions on how to enhance sputum expectoration. Sputum samples were processed using the N-acetyl-L-cysteine (NaLc-NaOH) method and stained with Auramine O. Sputum analysis was done with the aid of fluorescence microscopy. Following microscopy, both the 2.0ml and 5.0ml specimens were sent for culture using the Middlebrook broth medium, and culture results were available after 6-8 weeks. Using the culture results as gold standard, the yield through microscopy of the 2.0ml specimen versus the 5.0ml specimen for each patient were compared and analysed. RESULTS: A Total of 330 sputum samples were analysed of which 77 were found to be culture positive. A sensitivity of 76.6% and specificity of 99.6% was obtained for AFB test in the 5.0ml specimens; while in the 2.0ml samples the sensitivity was 75.3%, with a specificity of 99.2%. The difference in the smear positivity rate of 76.6% obtained using the 5.0ml sputum specimen compared to the 75.3% obtained using the 2.0ml specimen from patients suspected of having TB in this study was statistically insignificant – ascribable to the small sample size. CONCLUSION: In this study, the volume of sputum collected did not determine a better AFB test yield in the diagnosis of pulmonary tuberculosis in patients suspected of having TB.

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