• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 8
  • 8
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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.
1

Efficient Alternate Test Generation for RF Transceiver Architectures

Halder, Achintya 03 May 2006 (has links)
The production testing cost of modern wireless communication systems, especially basestation units, is estimated to be as high as 30-40 percent of their manufacturing cost and is increasing with system complexity, high levels of device integration and scaling of CMOS process technology and operating frequencies. The major production testing challenges for RF transceivers are: (a) the high cost of automated test development because of system-level simulation difficulties and the large simulation times involved, (b) the high cost of using high-end, communication protocol-aware RF test instrumentation, and (c) lack of external test access to RF circuits embedded inside integrated transceivers. Consequently, there exists a need for developing efficient design-for-test methodologies and non-invasive system-level test techniques for wireless transceivers to reduce their test cost. This dissertation is focused towards development of new system-level alternate test methodologies for RF transceiver architectures. The research proposes using non-invasive testing techniques for RF subsystems and digital-compatible built-in testing techniques for baseband and intermediate frequency (IF) analog circuits. The objectives of this research are: (a) to develop automatic test stimulus generation algorithms that allow accurate determination of targeted RF system-level test specification values using behavioral modeling and simulation techniques, (b) to develop RF transceiver test techniques that allow testing of embedded RF systems with limited test access, while reducing the test time for complex RF and baseband system-level performance metrics (b) to significantly reduce the test instrumentation overhead for testing complex frequency-domain and modulation-domain system specifications. The feasibility and the cost benefits of using the proposed alternate test approaches have been demonstrated using 900 MHz and 1575 MHz transceiver prototypes.
2

ANALYSES OF PRODUCTION TESTS AND MDT TESTS CONDUCTED IN MALLIK AND ALASKA METHANE HYDRATE RESERVOIRS: WHAT CAN WE LEARN FROM THESE WELL TESTS?

Kurihara, Masanori, Funatsu, Kunihiro, Ouchi, Hisanao, Masuda, Yoshihiro, Yamamoto, Koji, Narita, Hideo, Dallimore, Scott R., Collett, Timothy S., Hancock, Steve H. 07 1900 (has links)
Pressure drawdown tests were conducted using Schlumberger’s Modular Formation Dynamics Tester™ (MDT) wireline tool in the Mallik methane hydrate (MH) reservoirs in February 2002 as well as in the Mount Elbert (Alaska) MH reservoirs in February 2007, while a production test was conducted applying a depressurization method in one of the Mallik MH reservoirs in April 2007. All of these tests aimed at measuring production and bottomhole pressure (BHP) responses by reducing BHP below the MH stability pressure to estimate reservoir properties such as permeability and MH dissociation radius. We attempted to analyze the results of these tests through history matching using the numerical simulator (MH21-HYDRES) coded especially for gas hydrate reservoirs. Although the magnitude of depressurization and the total duration spent for these tests were almost identical to each other, the simulation studies revealed that there existed significant differences in what could be inferred and could not be inferred from test results between a MDT test and a production test. The simulation studies mainly clarified that (1) the MDT tests were useful to estimate initial effective permeability in the presence of MH, (2) when BHP is reduced below the MH stability pressure at MDT tests, the pressure and temperature responses were significantly influenced by the wellbore storage erasing all the important data such as those indicating a radius of MH dissociation and effective permeability after partial MH dissociation, and (3) history matching of production tests tended to result in multiple solutions unless establishing steady flow conditions. This paper presents the results of history matching for the typical MDT and production tests conducted in Mallik and Alaska MH reservoirs. This paper also discusses the parameters reliably estimated through MDT and production tests, which should provide many suggestions on future designs and analyses of short-term tests for MH reservoirs.
3

ANALYSIS OF THE JOGMEC/NRCAN/AURORA MALLIK GAS HYDRATE PRODUCTION TEST THROUGH NUMERICAL SIMULATION

Kurihara, Masanori, Funatsu, Kunihiro, Ouchi, Hisanao, Masuda, Yoshihiro, Yasuda, Masato, Yamamoto, Koji, Numasawa, Masaaki, Fujii, Tetsuya, Narita, Hideo, Dallimore, Scott R., Wright, J. Frederick 07 1900 (has links)
A gas hydrate production test using the depressurization method was conducted in early April 2007 as part of the JOGMEC/NRCan/Aurora Mallik production research program. The results of the production test were analyzed using a numerical simulator (MH21-HYDRES) coded especially for gas hydrate reservoirs. This paper evaluates the test results based on analyses of production test data, numerical modeling and a series of history matching simulations. Methane gas and water was produced from a 12 m perforation interval within one of the major methane hydrate (MH) reservoirs at the Mallik MH field, by reducing the bottomhole pressure down to about 7 MPa. The measured gas production rate was far higher than that expected for a comparatively small pressure drawdown. However, irregular (on-off) pumping operations, probably related to excessive sand production, resulted in unstable fluid flow within the wellbore, which made the analysis of test performance extremely complicated. A numerical reservoir model was constructed as a series of grid blocks, including those mimicking the wellbore, to enable rigorous simulation of fluid flow patterns in the vicinity of the wellbore. The model was then tuned through history matching, not by simply adjusting reservoir parameters, but by introducing the concept that sand production might have dramatically increased the near-wellbore permeability. The good agreement between observed and simulated performances suggests the mechanism of MH dissociation/production during the test. The history matched reservoir model was employed to predict the second-year production test performance, in order to examine the gas production potential of the Mallik MH reservoir, and to provide insight into future exploration and development planning for MH reservoirs.
4

WIRE-LINE LOGGING ANALYSIS OF THE 2007 JOGMEC/NRCAN/AURORA MALLIK GAS HYDRATE PRODUCTION TEST WELL

Fujii, Tetsuya, Takayama, Tokujiro, Nakamizu, Masaru, Yamamoto, Koji, Dallimore, Scott R., Mwenifumbo, Jonathan, Wright, J. Frederick, Kurihara, Masanori, Sato, Akihiko, Al-Jubori, Ahmed 07 1900 (has links)
In order to evaluate the productivity of methane hydrate (MH) by the depressurization method, Japan Oil, Gas and Metals National Corporation and Natural Resources Canada carried out a full scale production test in the Mallik field, Mackenzie Delta, Canada in April, 2007. An extensive wire-line logging program was conducted to evaluate reservoir properties, to determine production/water injection intervals, to evaluate cement bonding, and to interpret MH dissociation behavior throughout the production. New open hole wire-line logging tools such as MR Scanner, Rt Scanner and Sonic Scanner, and other advanced logging tools such as ECS (Elemental Capture Spectroscopy) were deployed to obtain precise data on the occurrence of MH, lithology, MH pore saturation, porosity and permeability. Perforation intervals of the production and water injection zones were selected using a multidisciplinary approach. Based on the results of geological interpretation and open hole logging analysis, we picked candidate test intervals considering lithology, MH pore saturation, initial effective permeability and absolute permeability. Reservoir layer models were constructed to allow for quick reservoir numerical simulations for several perforation scenarios. Using the results of well log analysis, reservoir numerical simulation, and consideration of operational constraints, a MH bearing formation from 1093 to 1105 mKB was selected for 2007 testing and three zones (1224-1230, 1238-1256, 1270-1274 mKB) were selected for injection of produced water. Three kinds of cased-hole logging, RST (Reservoir Saturation Tool), APS (Accelerator Porosity Sonde), and Sonic Scanner were carried out to evaluate physical property changes of MH bearing formation before/after the production test. Preliminary evaluation of RST-sigma suggested that MH bearing formation in the above perforation interval was almost selectively dissociated (sand produced) in lateral direction. Preliminary analysis using Sonic Scanner data, which has deeper depth of investigation than RST brought us additional information on MH dissociation front and dissociation behavior.
5

Cost modelling and concurrent engineering for testable design

Dick, Jochen Helmut January 1993 (has links)
As integrated circuits and printed circuit boards increase in complexity, testing becomes a major cost factor of the design and production of the complex devices. Testability has to be considered during the design of complex electronic systems, and automatic test systems have to be used in order to facilitate the test. This fact is now widely accepted in industry. Both design for testability and the usage of automatic test systems aim at reducing the cost of production testing or, sometimes, making it possible at all. Many design for testability methods and test systems are available which can be configured into a production test strategy, in order to achieve high quality of the final product. The designer has to select from the various options for creating a test strategy, by maximising the quality and minimising the total cost for the electronic system. This thesis presents a methodology for test strategy generation which is based on consideration of the economics during the life cycle of the electronic system. This methodology is a concurrent engineering approach which takes into account all effects of a test strategy on the electronic system during its life cycle by evaluating its related cost. This objective methodology is used in an original test strategy planning advisory system, which allows for test strategy planning for VLSI circuits as well as for digital electronic systems. The cost models which are used for evaluating the economics of test strategies are described in detail and the test strategy planning system is presented. A methodology for making decisions which are based on estimated costing data is presented. Results of using the cost models and the test strategy planning system for evaluating the economics of test strategies for selected industrial designs are presented.
6

Effektivität von Key-Feature-Prüfungen beim Erwerb der Kompetenz Clinical Reasoning in der medizinischen Ausbildung / Effectiveness of key feature examinations in the acquisition of the skill clinical reasoning in medical education

Andresen, Jil Cathérine 20 August 2020 (has links)
No description available.
7

LabView-baserat produktionstest för borstlösa trefasiga likströmsmotorer / LabView-based production test for brushless three phase direct current motors

Thulin, Marlene January 2019 (has links)
Testning är en viktig del i tillverkningskedjan för att säkerställa kvalitet och funktion hos elektronikprodukter, och utförs ofta på flera nivåer innan den färdiga produkten lämnar fabriken. Produktionstester är rutinmässiga tester som tillämpas under masstillverkning och vid utformning av dessa måste tidseffektivitet prioriteras för att minimera negativ inverkan på produktionstakten. I detta projekt överfördes ett produktionstest för färdigmonterade borstlösa DC-motorer med drivelektronik till en ny testutrustning hos företaget Allied Motion. Testet skulle moderniseras och införas i företagets mjukvaruplattform uppbyggd i programspråket LabView. Testsekvensen kunde effektiviseras främst genom att kombinera dess delmoment och låta körningar av motorn användas för att testa flera egenskaper istället för att upprepas. Resultatet blev ett test som täckte in samma mätningar som i det äldre systemet med undantag för enstaka moment, samt mätte hastighet och momentkarakteristik med högre precision. Det omarbetade testet bestod av fyra deltester jämfört med tidigare tolv steg, och implementerades i fyra LabView-baserade testfall som kunde användas för att skapa en komplett testsekvens i plattformen. Uppgiften visade sig dock kräva mer tid och arbete än vad som uppskattats inledningsvis, och därför återstod flera av de arbetsuppgifter som planerats inom projektet att slutföra innan det nya testet skulle kunna tas i bruk i produktionen. / Testing is an important part of the manufacturing process to ensure the functional quality of electronics products, and is often performed in multiple stages during product assembly before the final product leaves the factory. Production tests are applied as a routine on all units in a production line, therefore time efficiency must be prioritized in the design of such tests in order to minimize the negative effect imposed on production rate. In this project an existing production test for fully assembled brushless DC motors was re-implemented for a new test equipment at Allied Motion. The purpose was to modernize the test and implement it in the company’s own LabView-based software platform. The test sequence was streamlined by combining and thereby reducing the number of steps, using the same motor runs to test multiple functions rather than repeating run sessions to collect data for similar test steps. The project resulted in a new test that, with a minor exception, covered the same measurements as in the old system and measured speed and torque performance with higher precision. The new test consisted of four partial tests instead of the earlier version’s twelve test steps, which were implemented in LabView-code as four separate test cases that could be used in creating complete test sequences in the software platform. The project task though turned out to require more time and effort than was initially estimated, and several parts that had been planned to be completed within the project time still remained before the test could be taken into use in the production line.
8

Operator unit simulator / Operator unit simulator

Rasmussen, Nichlas January 2015 (has links)
Detta examensarbete utfördes som ett uppdrag av Atlas Copco där målet var att utveckla en programvara som kan simulera en OU (Operator Unit) i en PC miljö. Atlas Copcos egenutvecklade radiostyrningssystem för gruvfordon består av en sändare, kallad OU, och en mottagare, kallad MU (Machine Unit). En OU är en kontroller med reglage i form av knappar, joysticks och switchar och med indikatorer i form av LEDs och display. För att säkerställa att en OU endast kan kommunicera med en specifik MU och vice versa måste enheternas radiomoduler paras ihop genom en process som kallas ”learn link”, som görs genom att ansluta en CAN-kabel mellan enheterna.   Genom att använda en OU simulator vid MU produktionstest skulle det vara lättare att utföra vissa tester, såsom internfel och varningar, och det skulle vara möjligt att inkludera tester som är omöjliga att göra med en hårdvaru-OU, som att avsiktligt sända en felberäknad checksumma, för att undersöka MU-enhetens respons. OU simulatorn skulle ha ett grafiskt gränssnitt och genom att ansluta ett radiokort till PC:n skulle den kunna skicka och ta emot data från en MU. Den skulle också kunna utföra ”learn link”. Den färdiga produkten utvecklades med hjälp av C# och en XP-inspirerad utvecklingsmetod. / This thesis was developed as an assignment from Atlas Copco where the goal was to develop software that could simulate an OU (Operator Unit) in a PC environment. Atlas Copco’s proprietary radio-control system for mining vehicles consists of a transmitter, called OU, and a receiver, called MU (Machine Unit). An OU is a controller with controls in the form of buttons, joysticks and switches and with indicators in the form of LEDs and display. To ensure that an OU only can communicate with a specific MU and vice versa the units’ radio modules must be paired together through a process called “learn link”, that is performed by connecting the units with a CAN-cable.   By using an OU simulator for MU production tests it would be easier to perform some tests, such as internal errors and warnings, and it would be possible to include tests that are impossible to do with OU hardware, such as intentionally send a miscalculated checksum, to examine the MU’s response. The OU simulator should have a graphical user interface and by connecting a radio card to the PC it should be able to send and receive data from an MU. It should also be able to perform “learn link”. The final product was developed using C# together with an XP-inspired development method.

Page generated in 1.5426 seconds