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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.
71

Software Automation For Measurement-Based Behavioral Models Of Microwave

Sosa Martin, Daniel 18 June 2009 (has links)
This thesis presents a study and implementation of several measurement procedures used to efficiently generate non-linear measurement-based behavioral models primary for microwave amplifiers. Behavioral models are a solution for representing devices that can present linear and/or non-linear behavior when little or no information about the internal structure is known. Measurement-based behavioral models are an advantage since they can be extracted from a direct measurement of the device. This work addresses some of the challenges of these types of measurements. A set of software modules has been produced that combine several modern techniques to efficiently generate practical models using equipment commonly available in a typical microwave lab. Advanced models using new and more complex equipment are also discussed. Modeling of the non-linear operation of power amplifiers is a common subject of study since it provides a path to improved system simulations. However, the measurement process used for non-linear behavioral modeling of PAs requires either non-linear measurement instrumentation, not yet widely available, or numerous measurements that makes the process tedious and susceptible to errors. Power dependent S-Parameters obtained with a conventional Vector Network Analyzers (VNA) can be used to extract AM-to-AM and AM-to-PM behavior of a device and to generate, simple but useful, behavioral models. A careful analysis of the characteristics of common RF measurement instrumentation combined with knowledge of common non-linear phenomena provides with the conditions under which useful models can be generated. The results of this work are presented as several programs implemented in National Instruments LabVIEW that will sequence through the different measurements required for the generation of measurement-based behavioral models. The implemented models are known as P2D and S2D models available with Agilent Advanced Design System (ADS.) The code will communicate with the measurement instrumentation and decide on the most efficient way to extract the data. Once the data is extracted, the code will put into the appropriate syntaxes required by the model for direct and convenient setup of the generated models in ADS.
72

主機板製造廠商策略群組與經營績效關聯性之研究

陳學庸, Chen, Hsueh-Yung Unknown Date (has links)
本研究以策略群組(strategic groups)之觀念為核心,檢視我國主機板製造廠商是否存在不同之策略群組,同時並探討不同策略群組在經營績效上之表現。 本研究採用Hofer and Schendel(1978)之「領域」、「資源投入」、「競爭優勢」三個構面發展出24項競爭策略變數,經由因素分析萃取出二個因素構面,再利用層次式集群法對樣本廠商在二項因素構面進行分群。本研究經由上述分析過程得到3個策略群組,並以三者在策略因素構面上的表現分別命名為「前瞻者策略群」、「分析者策略群」及「防禦者策略群」。確認三個策略群組後,接著以無母數統計檢定三策略群組在市場、生產力、財務結構、償債能力、經營能力、獲利能力、現金流量、槓桿度與成長機會等九個經營績效構面上是否有顯著差異,實證結果發現三群組在大多數經營績效變數中均有顯著差異。 由於主機板製造廠商環境變動快速,且其客戶重視產品品質勝於價格,因此強調「外部導向」、顧客滿意度的前瞻者策略群在市場、經營能力與獲利能力等構面之績效最佳,兼具穩定與變化特質的分析者策略群次之,重視成本控制而專注維持穩定產品市場的防禦者策略群則最差。此外,由於前瞻者的理財態度多趨向保守,因而在財務結構、償債能力、現金流量與財務槓桿方面的表現顯得穩健。至於防禦者較佳的固定資產週轉率正好與其較低之營運槓桿相呼應,映證其為維持成本領先地位所作的成本控管。從應收款項週轉率、存貨週轉率與淨營業週期可以得知,防禦者利用與金融機構間的短期融資,並取得較寬鬆的應付帳款支付期限,壓低利息費用,因而產生較低之財務槓桿。 整體而言,前瞻者策略群在九項經營績效構面上表現最佳,因此,在主機板製造廠商中,採行前瞻者策略群的差異化策略,似乎能獲致較佳之經營績效表現。 / Based on the literature on strategic groups, this thesis first investigates the existence of strategic typology among twelve motherboard manufacturers in Taiwan, and then examines the differences in operating performance across strategic groups. Appeal to three strategic dimensions-scope, resources commitment and competitive advantage, proposed by Hofer and Schendel (1978), twenty-four strategy variables are developed. Employing a factor analysis approach first to extract two factor dimensions, and a hierarchical cluster method followed, three strategic groups are identified. The three strategic groups are named accordingly based upon their features shown on the common factor dimensions: Prospector, Analyzer and Defender respectively. Using a nonparametric statistical method, this thesis empirically tests the cross-group differences in operating performance. The empirical results indicate that there are significant cross-group differences in most of the operating performance dimensions examined in this thesis. Prospectors, with emphases on external orientation and customer satisfaction, outperform Analyzers and Defenders in the dimensions of market share, activity, and profitability. Defenders, with foci on cost control and stable product market have the lowest performance with aforementioned performance dimensions. Analyzers who put mixed emphasis on both external orientation and stable product market earn the second place in the related performance. With respect to dimensions of financial structure, liquidity, cash flow adequacy, and financial leverage, the findings indicate that Prospectors exhibit a more conservative attitude toward financing activities than Analyzers and Defenders. The results also show that in concert with their strategy in cost leadership, Defenders have higher fixed asset turnover accompanied with lower operating leverage. Defenders are also found to have lower financial leverage through obtaining an extended period of paying their account payables, which in turn reduce their interest expense.  Operating in a turbulent environment, manufacturers in the motherboard industry face customers who value quality more than prices. The empirical results found in this thesis thus suggest that it may be beneficial for participants in the industry to adopt a Prospectors strategy that seems to be able to reap from the product differentiation.
73

Visualisering av Flight Recorder-data i Saab 2000 avionikrigg

Åberg, Anders January 2006 (has links)
<p>The main purpose of a Flight Data Recorder (FDR) is to facilitate the investigation of incidents. In order to interpret the data that has been recorded in the FDR the data has to be visualized in some way. This can be done with software on a computer or with hardware that is specific for the model of aircraft that the data originates from.</p><p>The aim of this project is to visualize data for six parameters from the FDR of Saab 2000 in an avionics rig. The avionics rig resembles the cockpit of Saab 2000 and the displays in it are identical to the ones found in the plane. All six parameters are shown on the same display.</p><p>Due to safety regulation vital systems in aircraft are doubled, with one system on the left side and one on the right. Because of the architecture of the rig it was decided that data from the right-hand side systems were to be visualized on the right-hand side display. It is not possible to guarantee that no incorrect values are shown for the parameter altitude when values are taken from the right-hand side, but it can be done for values from the left side. This is the reason why values are taken from the left-hand side for altitude. In the rig a computer with an ARINC429-card and the software Data Bus Analyzer was accessible to transmit data to the displays. DBA can save received data in ASCII-files and also open and transmit the data in such files. Data that has been extracted from an FDR can be converted to the format which DBA can read with macros that have been written in the project. After conversion the data can be transmitted to the display on which it is supposed to be visualized.</p>
74

Evaluation of the ADVIA®60 on highvalue platelets

Ekbom, Lisa H January 2005 (has links)
<p>Platelets are the smallest cells in the blood. They are formed in the bone-marrow and are important for the blood coagulation. Platelet tranfusions are given to patients propyhlactically before an operation but also in therapeutical purpose in connection with bleeding. It’s importent that the quality controls of the platelet concentrates are reliable.</p><p>ADVIA®60 (Bayer HealthCare) is a fully automated cell counter which uses impedance principle to count platelets in blood samples. The purpose of the study was to evaluate this new instrument for use in the blood bank of Akademiska Sjukhuset in Uppsala. The instrument was bought to be used for quality control of platelet concentrates. 30 samples from platelet concentrates, from both apheresis and from buffy coats, were analyzed 10 times each on ADVIA®60 and the coefficient of variation (CV) was calculated for each sample. CV variated from 0,8 % to 2,9 % which is good considering that according to Bayer HealthCare the CV should be < 5 % for thrombocytes on ADVIA®60. The instrument was newly calibrated when the study was performed. Platelet count can also be performed by immunological or optical principles.</p>
75

Frequency Dependence Modulus of Pd₄₀Ni₁₀Cu₃₀P₂₀ Amorphous Alloy around the Glass Transition by Dynamic Mechanical Analysis

Lee, M.L., Li, Yi, Feng, Y.P., Carter, W. Craig 01 1900 (has links)
Dynamic Mechanical Analyzer (DMA) was used to study the frequency dependence of storage and loss modulus of amorphous Pd₄₀Ni₁₀Cu₃₀P₂₀ alloy over a broad frequency range around its glass transition temperature. The amorphous samples were subjected to two testing conditions: constant frequency with continuous heating and isothermal with frequency sweep. The storage modulus E′ exhibited a sigmoidal change from about 90 GPa to a low value of about 0 GPa over the glass transition region. The loss modulus, E″, was characterized by an asymmetrical peak with a smaller slope at the low temperature side than at the high temperature side upon heating. These changes in moduli were associated with mechanical relaxation due to atomic motion. Similar results were also obtained under isothermal condition. The Kohrausch-Williams-Watts function was used to fit the data obtained under the isothermal condition. The peak frequencies obtained were then fitted to the VFT equation and the scaling law equation. / Singapore-MIT Alliance (SMA)
76

pH Effect on the Arsenic Separation in Waste Water of Coal Based Power Plant

Hao, Ye 01 May 2010 (has links)
Arsenic (As) poses a significant water quality problem and it is a big challenge for all coal-based power plant industries worldwide. Currently most of the researches on the leaching behavior of arsenic from fly ash are based on the titration experiments. In this study a simulation method is used to study on the pH effect on the arsenic separation of coal-based power plants. Both single point and composition survey simulation of the OLI stream analyzer are used in the study. The simulation results of single point calculation indicates that for the fly ash which has high lime weight percent and equilibrium fly ash solution pH is over 11 and between 7 and 9, that is, Type C fly ash, the simulation results for equilibrium pH in fly ash solutions have great accuracy compared to actual experiment results. Based on the results obtained from single point simulation, both acid and base titrations of composition survey are simulated and the output results suggest that for the same type of fly ash, the simulation results proves the general trend of arsenic solubility in fly ash solutions. The solubility of arsenic decreases with the increase of pH value. It is also noted that at the equilibrium pH fly ash solutions, the maximum solid/liquid ratio of arsenic concentration is observed for type C fly ash. For other fly ashes which have low lime weight percent, the simulation results have discrepancy compared to actual experiment results. This work is important in offering an alternative way of analyze the reasonable output species and relative concentrations for type C fly ash in the waste water storage pond under specific pH conditions, which can be of great importance for the power plants to monitor and minimize the environment pollution in order to meet the future federal regulations.
77

Development of a Method for Measuring Pasta Quality Parameters

Haraldsson, Jörgen January 2010 (has links)
In this work the objective was to develop a method that would make it easier to quantitatively evaluate different quality parameters in pasta. This was done with the assistant of a texture analyzer from TexVol Instruments. The quality parameters that were investigated were hardness, resilience, elasticity and adhesiveness. Two different types of measurements were used to measure three different pasta brands. These were single cycle and hold until time. Before this was done the main parameters in the texture analyzer were tested and adjusted to suite the method. Most of the steps in the developed method worked satisfactorily but more studies have to be done to make the method useful in the daily work with pasta production and pasta development. With all tests in mind it could be said that the De Cecco pasta was the one with the best texture parameters. It had the highest hardness, elasticity and resilience and the lowest adhesiveness. The other two brands, Kungsörnen and Tomadini had lower but similar results. Further important studies to look into is if there`s a possibility to get a computer software that are more targeted on pasta measurement. Another important thing is if these pasta measurements can be done in a different way, perhaps just using a few spaghetti straws. It would also be interesting to study the protein network in an electron microscope because then it´s easier to understand what´s happening when pasta is prepared. Last but not least I think it´s important to do a organoleptic test to see if it´s possible to taste the measured results. / Detta examensarbete gick ut på att ta fram en metod med hjälp av en texturmätare där olika kvalitetsparametrar såsom hårdhet, elasticitet och spänst kunde mätas på pasta. Dessa mätningar gjordes på tre olika spaghettimärken. Dessa var Kungsörnen, Tomadini samt De Cecco. Mätningarna på de olika pastamärkena gjordes med hjälp av en texturmätare från TexVol som är ett svenskt företag. Deras olika instrument är främst framtagna för att fungera inom bageribranchen och köttindustrin. Detta gjorde att det var spännande att se om detta instrument även kunde användas med framgång för att mäta olika kvalitetsegenskaper på kokt pasta. Först gjordes mätningar på Kungsörnens spaghetti vid olika koktider. Dessa var mellan 5 och 14 minuter. Dessa mätningar gjordes främst för att se vad som händer med de olika kvalitetsegenskaperna från det att pastan är underkokt till kraftigt överkokt. Utifrån resultaten från dessa mätningar är det svårt att dra några tydliga slutsatser då de varierade kraftigt. Därefter gjordes mätningar på de tre olika pastamärkena med två olika mätmetoder, dels single cycle och dels hold until time. Med single cycle menas att proben(mätstången) går ner i pastan och sen direkt upp igen medan vid hold until time metoden så går proben ner för att sen stanna nere tills en förinställd tid passerat innan den går upp igen. På detta sätt kan olika kvalitetsegenskaper mätas med de olika mätmetoderna. För att dessa mätmetoder ska fungerar har olika parametrar på texturmätaren utvärderats och på detta sätt har en metod/tillvägagångssätt tagits fram. De flesta av stegen i denna metod verkar fungera bra men ett stort problem är att mätningarna skiljer sig mycket åt. Detta beror troligtvis på att pastan lägger sig olika inför varje mätning vilket gör att mätningarna blir långt ifrån identiska vilket leder till att resultaten blir svårtolkade. Vissa tendenser kan dock ändå ses. Om alla mätningar tags i beaktande kan det sägas att De Cecco pastan är den pasta av högst kvalité. De Cecco pastan är den som är mest "al dente", mest elastisk, mest spänst samt lägst klibbighet. Vad detta beror på är svårt att säga då det kan finnas många förklaringar som är mer eller mindre relevanta. En trolig förklaring kan vara att De Cecco pastan har ett högre proteininnehåll än de båda andra märkena. I litteraturen står det att ett högre proteininnehåll ger en bättre kokt pasta och detta verkar rimligt då protein nätverket blir starkare vilket håller ihop pastan på ett bättre sätt. En annan möjlig orsak kan vara att fördelningen av de olika proteinerna är bättre i De Cecco pastan än i de andra märkena vilket leder till en bättre kvalitet. De två andra, Kungsörnen och Tomadini hade snarlika resultat. Vad som behöver göras för att denna metod eventuellt ska kunna användas i den dagliga produktionen av pasta och utveckling av ny pasta är att ta bort så många felkällor som möjligt så att standardavvikelsen i alla mätningar blir avsevärt mindre. Detta kan kanske avhjälpas av att ha en mjukvara som är mer anpassad till pastamätningar än den som var används nu som är anpassad till bageribranchen. En annan viktig sak kan vara att mäta på bara några få pasta strå till skillnad mot nuvarande "spaghettinystan". Ytterligare en intressant sak är att göra en organoleptisk undersökning av de olika pastamärkena för att se om de uppmätta resultaten är smakbara. Även att titta i elektronmikroskåp för att se de olika spaghettis proteinnätverk kan vara intressant för att få en förståelse för hur pastan ändrar sig under kokning.
78

Analysis of Human Motion in Rehabilitation by Micro-Computer

ITO, FUJIO 03 1900 (has links)
No description available.
79

Mechanical support design of analyzer for a diffraction enhanced x-ray imaging (DEI) system

Alagarsamy, Nagarajan 18 May 2007
Diffraction Enhanced X-ray Imaging (DEI) uses synchrotron X-ray beams prepared and analyzed by perfect single crystals to achieve imaging contrast from a number of phenomena taking place in an object under investigation. The crystals used in DEI for imaging requires high precision positioning due to a narrow rocking curve. Typically, the angular precision required should be on the order of tens of nanoradians.<p>One of the problems associated with DEI is the inability to control, set, and fix the angle of the analyzer crystal in relation to the beam exiting the monochromator in the system. This angle is used to interpret the images acquired with an object present and the usual approach is to determine where the image was taken after the fact. If the angle is not correct, then the image is wasted and has to be retaken. If time or dose is not an issue, then retaking the image is not a serious problem. However, since the technique is to be developed for live animal or eventually human imaging, the lost images are no longer acceptable from either X-ray exposure or time perspectives.<p>Therefore, a mechanical positioning system for the DEI system should be developed that allows a precise setting and measurement of the analyzer crystal angles. In this thesis, the fundamental principles of the DEI method, the DEI system at the National Synchrotron Light Source (NSLS) and the sensitivity of the DEI system to vibration and temperature has been briefly studied to gain a better understanding of the problem. The DEI design at the NSLS was analyzed using finite element analysis software (ANSYS) to determine the defects in the current design which were making the system dimensionally unstable. Using the results of this analysis, the new analyzer support was designed aiming to eliminate the problems with the current design. The new design is much stiffer with the natural frequency spectrum raised about eight times. <p> This new design will improve the performance of the system at the National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory, New York, USA and should assist in the development of a new DEI system for the Bio-Medical Imaging and Therapy (BMIT) beamline at the Canadian Light Source (CLS), Saskatoon, CANADA.
80

Evaluation of the ADVIA®60 on highvalue platelets

Ekbom, Lisa H January 2005 (has links)
Platelets are the smallest cells in the blood. They are formed in the bone-marrow and are important for the blood coagulation. Platelet tranfusions are given to patients propyhlactically before an operation but also in therapeutical purpose in connection with bleeding. It’s importent that the quality controls of the platelet concentrates are reliable. ADVIA®60 (Bayer HealthCare) is a fully automated cell counter which uses impedance principle to count platelets in blood samples. The purpose of the study was to evaluate this new instrument for use in the blood bank of Akademiska Sjukhuset in Uppsala. The instrument was bought to be used for quality control of platelet concentrates. 30 samples from platelet concentrates, from both apheresis and from buffy coats, were analyzed 10 times each on ADVIA®60 and the coefficient of variation (CV) was calculated for each sample. CV variated from 0,8 % to 2,9 % which is good considering that according to Bayer HealthCare the CV should be &lt; 5 % for thrombocytes on ADVIA®60. The instrument was newly calibrated when the study was performed. Platelet count can also be performed by immunological or optical principles.

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