International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The Global Positioning System (GPS) is a very accurate, all-weather, world wide three dimensional navigation system and it has been used in almost every field related to positioning and navigation. This paper presents a new application of GPS technology - personal positioning and navigation system. It combines VP ONCORE receiver OEM (Original Equipment Manufacture) board and an intelligent system controller, with a keyboard and a programmable LCD as its peripherals. This system can realize rich navigation functions and satisfy the need of personal use.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper investigates the feasibility of using commercial satellite constellations to relay telemetry data from flight test vehicles as part of a Global Test Range. The use of a commercial satellite constellation would provide an augmented capability to the test range, providing near real-time data to the data reduction site and test range control at reasonable cost. This includes an analysis of current and proposed commercial communication satellite constellations to determine if any of them would fulfill the needs of a telemetry test range. Preliminary assessment of the communication link between a flight vehicle and the satellite constellations is performed.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The Equipment Time-Delay (ETD) measurement technology for Continuous Wave (CW) transponder is discussed with emphasis on the principle of measuring the ETD of the intermediate frequency (IF) modulation transponder through measuring subcarrier modulation sideband tone phase. A general method for measuring ETD of different types of transponder (including IF-modulation transponder) is introduced. Finally the measurement method error is analyzed.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Next generation flight termination systems (FTSs) will use digital technologies to verify the authenticity of range safety commands by command receiver-decoders located on each vehicle. This paper will discuss the general principles behind simplex message authentication using a block encryption cipher, and presents examples for demonstration.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / It has been shown that a multi-symbol detector can improve the detection efficiency of PCM/FM by 3 dB when compared to traditional methods without any change to the transmitted waveform. Although this is a significant breakthrough, further improvements are possible with the addition of Forward Error Correction (FEC). Systematic redundancy can be added by encoding the source data prior to the modulation process, thereby allowing channel errors to be corrected using a decoding circuit. Better detection efficiency translates into additional link margin that can be used to extend the operating range, support higher data throughput, or significantly improve the quality of the received data. This paper investigates the detection efficiency that can be achieved using a multisymbol detector and turbo product coding. The results show that this combination can improve the detection performance by nearly 9 dB relative to conventional PCM/FM systems. The increase in link margin is gained at the expense of a small increase in bandwidth and the additional complexity of the encoding and decoding circuitry.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The U.S. Air Force has developed GPS-based instrumentation systems to support both test and training activities. In support of recent large-scale exercises, interfaces were developed to employ existing test and training assets in a synthetic battlefield. The writers propose exploration of similar approaches to overcome the challenge of developing a common approach to test and training instrumentation.

在無線區域網路的範疇，IEEE 802.11是一個主要的媒介存取控制協定。然而在隨意式多跳接的網路中，IEEE 802.11面臨更嚴重的hidden terminal和exposed terminal problems，而這些問題主因都源自於過大的訊號干擾範圍與過大的訊號感應範圍。在這篇論文裡，我們提出一個可調式的媒介存取控制協定，針對IEEE 802.11 RTS/CTS handshake機制做簡單地修改，使得IEEE 802.11 devices可以依據週遭的傳收狀態動態調整自身的傳送和接收行為。實驗結果顯示我們的方法使原來的 802.11 減少了互相干擾的情形並且提升了系統的效能。 / The IEEE 802.11 standard is the most popular Medium Access Control (MAC) protocol for wireless local area networks. However, in multihop wireless ad hoc networks, the IEEE 802.11 MAC protocol will suffer from more serious hidden terminal and exposed terminal problems than those in single hop WLANs. More specifically, it is due to the large interference range and the large carrier sensing range. In this thesis, we propose an adaptive IEEE 802.11 MAC (AMAC) that makes two simple modifications of IEEE 802.11 RTS/CTS handshake to dynamically adjust the transmission and reception according to the shared medium status near transmitter and receiver, respectively. Simulation results show that our method can lessen interferences and increase system throughput as compared with IEEE 802.11 MAC.

Cette thèse porte sur les mesures expérimentales des γ-prompts créés lors de la fragmentation du faisceau d'ions carbone en hadronthérapie. Deux expériences ont été effectuées aux laboratoires GANIL et GSI avec des ions 12C6+ de 95MeV/u et 305MeV/u irradiant une cible d'eau ou de PMMA. Dans les deux expériences une nette corrélation a été obtenue entre le parcours des ions carbone et le profil longitudinal des γ- prompts. Une des plus grandes difficultés de ces mesures vient de la discrimination entre le signal des γ-prompts (qui est corrélé avec le parcours des ions) et un important bruit de fond dû aux neutrons (non corrélé au parcours). Deux techniques sont employées pour effectuer la discrimination entre γ et neutrons: le temps de vol (TDV) et la discrimination par forme de signal (DFS). Le TDV a permis de démontrer la corrélation entre la production de γ-prompts et le parcours des ions. La DFS a fourni des informations précieuses pour la compréhension des caractéristiques des spectres en TDV. Dans ce travail on a démontré qu'un système de détection de γ-prompt collimaté, basé sur la technique du temps de vol, peut permettre une vérification en temps réel de la position du Pic de Bragg en conditions cliniques. Dans la dernière partie de la thèse, un travail de simulation a été effectué à l'aide du code de simulation Geant4 pour évaluer l'influence des principaux paramètres du design d'un dispositif de multi-détecteurs et multicollimateurs sur la résolution spatiale et l'efficacité atteignable par une Camera γ-Prompt. Plusieurs configurations géométriques ont été étudiées de façon systématique et les principales contraintes du design sont analysées.

Sediment deposit ages inferred from radiocarbon dating of stream bank material were used to estimate residence times of valley-floor deposits in headwater valleys of the Oregon Coast Range, USA. Inherited ages of radiocarbon-dated material, i.e., time between carbon fixation in wood and its incorporation in a sediment deposit, can result in over-estimation of the ages of those deposits and, hence, the residence times of sediment within those units. Calibrated radiocarbon dates of 126 charcoal pieces sampled from Knowles Creek were used to estimate the distribution of inherited ages in fourteen depositional units representing three deposit types: fluvial fines, fluvial gravels, and debris flows. Within a depositional unit, the inherited age distribution of a piece of charcoal was estimated by convolving its calibrated age distribution with that of the piece of charcoal with the smallest weighted-mean calibrated age (i.e., an approximation of a unit's date of deposition) within that unit. All inherited age distributions for a particular deposit type were then added and normalized to provide a probability distribution of inherited ages for that deposit type. Probability distributions of inherited ages average 688, 1506, and 666 yr for fluvial fines, fluvial gravels, and debris flow units, respectively. Curves were fit to inherited age distributions for each deposit type. These curve fits were then convolved with deposit age distributions (i.e., equal to calibrated age distributions of woody material sampled from stream banks) of samples from Bear Creek (Lancaster and Casebeer, 2007) to correct these deposit ages for inherited age. This convolution gives a corrected deposit age. In cases in which means of corrected deposit age distributions for an upper unit were older than those of a lower unit within a stratigraphic column, the upper sample’s corrected deposit age distribution was set to that of the youngest lower in the stratigraphic section. Convolution shifted individual deposit age distributions towards zero and increased their standard deviation by an average of 365%. However, convolution decreased the standard deviations of normalized probability distribution functions of deposit ages inferred from many samples from 1340 to 1197 yr, and from 471 to 416 yr for lower and upper reaches, respectively, of the Bear Creek valley in the Oregon Coast Range. Convolution decreased estimates of mean deposit ages from 1296 to 1051 yr, and from 308 to 245 yr for lower and upper reaches, respectively, of the Bear Creek. Estimates of percentages of basin denudation passing through each reach's deposit ("trapping efficiency") increased from 11.6% to 14.4%, and from 25.4% to 31.9% for lower and upper Bear Creek, respectively. However, basic shapes of residence time distributions and, thus, inferences regarding removal of sediment from the reaches did not change after deposit dates were corrected. Sediment residence times in the lower Bear Creek valley are exponentially distributed, which implies that all sediment has a uniform probability of evacuation from deposits, whereas the power-law-distributed residence times in upper Bear imply preferential evacuation of younger deposits and preservation of older deposits. Much of the sediment transported onto valley floors via debris flows is deposited, and then is evacuated over longer times. Volumes and residence times of stored sediment in these deposits at the transition from debris flow to fluvial evacuation, and their associated width of valley floors, vary throughout a network. Export volumes and frequencies from tributaries are controls on deposit volumes and may control valley widening of mainstem valley floors. In addition, closely spaced tributaries may exert composite effects on valley floor landforms. It is hypothesized that the volumes of sediment stored at confluences increases with contributing watershed area of tributaries to the point where tributary slopes are low enough to cause most debris flows to be deposited within tributary valleys instead of in the mainstem valley. In four ~1 km reaches with contributing watershed areas of 0.3 to 5.0 km², field surveys provided measures of width of valley floors and volume of deposits, and radiocarbon dating of charcoal provided residence times of sediment in these deposits. Mean residence times of reaches vary between 1.1 and 2.5 kyr. Exponential distributions fit to residence times within two of the reaches imply evacuation of sediment independent of deposit ages. Power-law fits to residence times of the other two reaches imply age-dependent evacuation of deposits. Distribution shapes of residence times, and their means, do not vary systematically with contributing watershed area of mainstems. Mean width of mainstem valley floors increases with contributing watershed areas of both mainstems and their respective tributaries. Volumes of sediment stored on the valley floor increase with contributing areas of mainstems, and these volumes at tributary junctions peaked at tributary contributing areas of ~0.1 km². Percentage of basin denudation entering storage decreases with contributing area of mainstem. This decrease may be due to increasing percentages of sediment supply via fluvial transport for larger watersheds, and much, if not most, of this supply routes through the system quickly. / Graduation date: 2012

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