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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.
1

GTRS och dess funktioner i Nordic Battlegroup 2011 / GTRS and its functions in the Nordic Battlegroup 2011

Saltin, Peter January 2010 (has links)
<p>Denna uppsats behandlar den nya prototypen för radiosystem som tagits fram inom projektet GTRS. Systemet jämförs med det äldre taktiska radiosystemet Radio 180 för att få fram vad som egentligen skiljer mellan dessa. Därefter behandlas Nordic Battlegroup 2011, där det utreds vilka uppgifter förbandet skall klara av och några typfall baserat på uppgifterna. Uppbyggnad och funktion för förbandets sambandssystem beskrivs också där själva kommunikationsnätet från Sverige till missionsområde avhandlas. Även de olika radioapparaterna som nyttjas och deras användningsområde behandlas. Detta används senare i en analys där först radioapparaternas skillnader utreds, därefter analyseras vad införandet av detta nya radiosystem skulle innebära för förbandet Nordic Battlegroup 2011. Uppsatsen kommer fram till att även om GTRS erbjuder ett merflexibelt nät med högre dataöverföringskapacitet än Ra 180 så finns det fortfarande utvecklingspotential innan det når full duglighet. Detta beror på att övriga delar som skulle kunna dra nytta av den högre dataöverföringshastigheten ännu inte är anpassade till detta. Därför är Ra 180 med sin DART och längre räckvidd fortfarande ett gångbart system, även om GTRS möjligheter kommeratt öka i takt med att ny kringutrustning införs.</p> / <p>This essay discusses the new prototype radio system developed by the project GTRS. This system is compared to the older tactical radiosystem Radio 180 to research what differences there are between the two. The Nordic Battlegroup 2011 is also presented, mainly which tasks the unit is supposed to beable to handle and some likely scenarios based on these tasks. The communications systems in the unit, from headquarters in Sweden and down to soldier level are presented complete with different radios used and what their capabilities are. After that, an analysis of the differences between the two radios is made which is followed by an analysis of what the introduction of GTRS could mean for the Nordic Battlegroup 2011. This analysis looks at both the technical and the tactical implications. The essay concludes that even though GTRS provides a more flexible net with higher bandwidth than Radio 180 there still is room for improvement before it can reach full usability. This is mainly because other parts of the system that could make use of the higher bandwidth are not yet adapted to this. That is why Radio 180 with the DART and its longer range of transmission still is capable system with the exception that the possibilities of GTRS will expand when new compatible peripherals.</p>
2

GTRS och dess funktioner i Nordic Battlegroup 2011 / GTRS and its functions in the Nordic Battlegroup 2011

Saltin, Peter January 2010 (has links)
Denna uppsats behandlar den nya prototypen för radiosystem som tagits fram inom projektet GTRS. Systemet jämförs med det äldre taktiska radiosystemet Radio 180 för att få fram vad som egentligen skiljer mellan dessa. Därefter behandlas Nordic Battlegroup 2011, där det utreds vilka uppgifter förbandet skall klara av och några typfall baserat på uppgifterna. Uppbyggnad och funktion för förbandets sambandssystem beskrivs också där själva kommunikationsnätet från Sverige till missionsområde avhandlas. Även de olika radioapparaterna som nyttjas och deras användningsområde behandlas. Detta används senare i en analys där först radioapparaternas skillnader utreds, därefter analyseras vad införandet av detta nya radiosystem skulle innebära för förbandet Nordic Battlegroup 2011. Uppsatsen kommer fram till att även om GTRS erbjuder ett merflexibelt nät med högre dataöverföringskapacitet än Ra 180 så finns det fortfarande utvecklingspotential innan det når full duglighet. Detta beror på att övriga delar som skulle kunna dra nytta av den högre dataöverföringshastigheten ännu inte är anpassade till detta. Därför är Ra 180 med sin DART och längre räckvidd fortfarande ett gångbart system, även om GTRS möjligheter kommeratt öka i takt med att ny kringutrustning införs. / This essay discusses the new prototype radio system developed by the project GTRS. This system is compared to the older tactical radiosystem Radio 180 to research what differences there are between the two. The Nordic Battlegroup 2011 is also presented, mainly which tasks the unit is supposed to beable to handle and some likely scenarios based on these tasks. The communications systems in the unit, from headquarters in Sweden and down to soldier level are presented complete with different radios used and what their capabilities are. After that, an analysis of the differences between the two radios is made which is followed by an analysis of what the introduction of GTRS could mean for the Nordic Battlegroup 2011. This analysis looks at both the technical and the tactical implications. The essay concludes that even though GTRS provides a more flexible net with higher bandwidth than Radio 180 there still is room for improvement before it can reach full usability. This is mainly because other parts of the system that could make use of the higher bandwidth are not yet adapted to this. That is why Radio 180 with the DART and its longer range of transmission still is capable system with the exception that the possibilities of GTRS will expand when new compatible peripherals.
3

Data Relay System for Space Shuttle and Payload Pre-Launch Checkout

O'Donnell, Hugh B., Wise, Thomas E., Ngo, David Q. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California / Engineering requirements and design characteristics of the coherent throughput relay system which supports East Coast pre-launch checkout of NASA's Space Shuttle and its Payloads are presented. The Relay system is required to provide communications through NASA's Tracking and Data Relay Satellite System for the Shuttle and Payload-Users while they are encapsulated in the launch preparation facilities at the John F. Kennedy Space Center and the Eastern Test Range, Florida. The Relay system is required to be transparent to its users' data at all rates up to three MB/s at S-band and 300 MB/s at Ku-band. Noise and group-delay distortion are major contributors to wide band RF signal degradation. These were major factors in the Relay system design. Antenna design, pointing angle and location were constrained by the need to maximize end-to-end RF signal isolation at both S-band and KU-band, simultaneous forward and return frequencies. System characteristics and link analysis are also presented. In addition, a similar Data Relay located at Vandenberg Air Force Base is briefly described.
4

Imaging Solar Cells Using Terahertz Waves

Kayra, Seda 01 January 2011 (has links) (PDF)
In this thesis, Terahertz Time-Domain spectroscopy (THz-TDS) was used in order to measure the electrical properties of silicon solar cells. The advantage of THz-TDS is that it allows us to measure the electrical properties without electrical contacts. In order to perform these measurements, a reflection based system was constructed and the changes in the peak amplitude in the time-domain under a, 450mW 808 nm continuous wave laser source were measured. The solar cell that was used in this thesis was manufactured in Middle East Technical University Microelectromechanical Systems (METU-MEMS) research laboratories located in Ankara, Turkey. The solar cell that we used in the measurements had a thickness of 0.45 mm and was produced on a single silicon crystal in &lt / 100&gt / direction. It is made up of a p-type base and n-type emitter to create p-n junction. Also, it has a Si4N3 AR coating and Al back contacts on it. To compare the THz measurements to that of electrical measurements, some electrical contact measurements were performed on the solar cell under laser illumination. By using these measurements, the energy conversion efficiency and the quantum efficiency of the solar cell were calculated and measured as 3.44 % and 7%, respectively under the 450mW, 808nm illumination on a specific area of the cell. The results that were obtained form the electrical measurements were compared with the THz results. We found that in order to understand the efficiency of the solar cell using THz-TDRS, a more comprehensive study needs to be done where the changes in the reflection of the THz radiation under different excitation powers and different configurations of the system need to be studied.
5

NON-GIMBALED ANTENNA POINTING

Vigil, Jeannine S. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper details the interaction of a small satellite with a space network and estimates the number of contacts and duration of contacts between the small, spin-stabilized satellite and a TDRS satellite. The simulations were performed using Satellite Tool Kit (STK) version 3.0, an orbital analysis software program. STK was configured for the four vehicles representing the spin-stabilized satellite and three TDRS satellites, TDRS East, West, and TDRS Zone of Exclusion. A set of simulations were run in which the spinstabilized satellite was given orbital elements corresponding to an orbital altitude between 600 km and 1200 km. The orbital inclination angle for the set of simulations was also varied from 20° through 100° along with the antenna cone angle of 10° through 40° to account for the effective beamwidths. In each of the simulations, the access to each TDRS satellite in the SN constellation was examined as a function of orbital altitude, orbital inclination angle, and antenna cone angle.
6

建築容積轉移制度運用於解決既成道路問題之研究 / TDR compositing in private Land Requiment for Exisiting Public Acess

劉厚連, Liu, Hou-Lien Unknown Date (has links)
過去政府對於私有既成道路用地,除限制其使用外,並不積極辦理徵收補償,司法院大法官會議第四百號解釋明確指出,既成道路在私有土地上成立公用地役關係,導致土地所有權人財產權之損害,各級政府應依法辦理徵收補償。然目前各級政府財政困難,全面採徵收補償方式辦理,有財政難以負荷之困境。因此,本研究嚐試將美國發展權移轉/容積轉移制度運用於解決既成道路之問題,期能建立一個能減輕政府財政支出的既成道路用地取得方式。 本研究先就發展權移轉制度之應用與限制加以探討,藉以了解其是否具有解決既成道路用地問題之可能。其次就目前既成道路之問題加以分析,比較各種用地取得方式之優劣,並透過政策評估指標的建立與專家問卷分析的運用加以檢視,得出建築容積轉移制度是目前政府解決既成道路問題方法中的最佳方案。 為使建築容積轉移制度運用於解決既成道路用地取得問題之構想落實,本研究除試擬建築容積轉移的運用流程外,並就可能遭遇之課題加以分析,透過專家問卷調查之方式,評選較優之解決方案以回饋建立制度執行時的配合措施。此外,本研究採用財務分析方式模擬個案在建築容積轉移過程中是否對供需雙方產生經濟的利益,以佐證本研究先前建立之制度在經濟上的可行性。根據模擬試算的結果顯示。制度之實施使既成道路地主及開發者雙方,皆有機會獲得較多的利益。 本研究認為從財產權保護之觀點,政府有必要積極解決私有既成道路之問題。而利用本研究建立之建築容積轉移方式應可使政府在不須花費龐大的經費支出下順利解決問題,惟制度實施之初須考慮相關的配套措施及先以試行方式取得實施經驗,才能使建築容積轉移制度發揮其效用。
7

海外企業來台上市異常報酬之研究-與國內企業新上市股票比較 / A study on abnormal returns of Taiwan listings by foreign issuers-compare with IPOs by domestic issuers

鄧彥農 Unknown Date (has links)
近年來,我國政府大力推動海外企業來台上市,成效亮眼。在這股熱潮下,為了解海外企業第一上市新股和第二上市台灣存託憑證於我國資本市場掛牌後的表現,本研究針對2009年四月至2010年十二月間,外國與本國發行人在台灣證券交易所新上市之股票和台灣存託憑證進行實證分析。除檢定其是否存在異常報酬外,並綜合過往文獻、相關法令規範及迴歸分析結果,探討影響其異常報酬的可能原因。本研究主要發現如下: (1)國內外企業在台新上市股票及台灣存託憑證均具有顯著的期初異常報酬,其高低依序為-海外企業第一上市新股、國內企業新上市股票、海外企業第二上市台灣存託憑證。 (2)台灣存託憑證期初異常報酬的成因並非來自於承銷價格的低估,而是來自於投資人對於蜜月行情的過度反應。其主要證據為-平均達3%的發行溢價、蜜月期結束後顯著為負的累積異常報酬、及對期初異常報酬最具影響力的示範效果因子。 (3)國內企業在台新上市股票期初異常報酬的成因主要來自於承銷商與發行公司資訊不對稱所造成的承銷價格低估。其主要證據為-新股上市後穩定且接近1.5%的累積異常報酬、及對期初異常報酬最具影響力的折價幅度因子。 (4)海外企業來台第一上市新股異常報酬的成因可能部分來自於發行公司與投資人資訊不對稱所造成的承銷價格低估;部分則可能來自於投資人對蜜月行情的過度反應。其主要證據為-蜜月期結束後為負的累積異常報酬、及海外企業來台第一上市新股與國內新上市股票的合併資料迴歸中,群體效果、中籤率與海外第一上市名目變數等顯著影響因子的間接支持。 / This study attempts to investigate the different patterns of the abnormal returns of Taiwan listings by foreign issuers and IPOs by domestic issuers, for the period from April, 2009 through December, 2010. Of particular interest is to examine the determinants of the abnormal returns. The major findings of the study are as the follows: (1)Empirical results indicate that all Taiwan listing stocks, including IPOs by foreign and domestic issuers and TDRs, have significant abnormal initial returns. Among them, IPOs by foreign issuers show the highest abnormal initial returns while TDRs show the lowest. (2)Evidences like the negative CARs, the average 3% premium of TDR issuance and the demonstration effect suggest that investor overreaction could be a major factor contributing to TDRs’ significant abnormal initial returns. (3)Evidences also suggest the under-pricing by the better-informed underwriters may cause significant abnormal initial returns of IPOs by domestic issuers. The IPO discount is discussed as an in-depth demonstration. (4)The study assumes that the significant abnormal initial returns of IPOs by foreign issuers partly result from the under-pricing as a signal to attract investors, and partly result from investor overreaction.

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