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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.
31

Testing the interference susceptibility characteristics of automatic direction finding receivers

Mullins, Thomas Howard January 1982 (has links)
No description available.
32

The design and implementation of tracking and filtering algorithms for an aircraft Beacon collision warning system

Ewing, Jr, Paul Lee January 1989 (has links)
No description available.
33

Conception, élaboration et caractérisation photophysiques et biochimiques de molécules photoactivables pour la thérapie photodynamique / Selective antitumor effect in PhotoDynamic Therapy mediated by photo-activable molecules, activated by endopeptidases

Verhille, Marc 25 October 2012 (has links)
L'angiogenèse est une étape clef dans le processus de progression tumorale. Elle est caractérisée par une surexpresssion d'un grand nombre de métalloprotéinases matricielles (MMP). Parmis ces MMP, les gélatinases (MMP-2 et MMP-9) sont connues pour jouer un rôle important dans l'angiogenèse tumorale et la croissance de nombreux cancers. Les "Photodynamic Molecular Beacon" (PMB) sont des constructions moléculaires qui peuvent être utilisées dans le traitement de cancers en associant un photosensibilisateur (PS) de type chlorine et un inhibiteur d'états excités, aussi appelé "Quencher", liés par un peptide substrat des gélatinases afin d'inhiber la toxicité du PS dans les cellules non ciblées, et de restaurer sa toxicité uniquement à proximité des gélatinases. Nous avons donc cherché à déterminer le couple PS/quencher permettant la meilleure inhibition de la production d'oxygène singulet, principale source de la toxicité du PS, puis avons synthétisé une famille de PMB ciblant les gélatinases. Différents peptides et bras espaceurs ont été utilisés pour évaluer l'influence de la distance entre le PS et le quencher sur les propriétés photophysiques et l'activation enzymatique du PMB / Angiogenesis is a key step in the tumoral progression process. It is characterized by an over-expression of a number of matrix metalloproteinases (MMP). Among these MMPs, gelatinases (MMP-2 and MMP-9) are known to play a critical role in tumor angiogenesis and the growth of many cancers. Photodynamic Molecular Beacons (PMB) can be designed for cancer treatment by associating a chlorin-like photosensitizer and a black hole quencher linked by a gelatinase substrate peptide with the aim of silencing photosensitizer toxicity in non-targeted cells and restore its toxicity only in surrounding gelatinases. We investigated the PS/quencher pair allowing the best singlet oxygen production inhibition, and then we synthesized a novel family of PMB triggering gélatinases MMP-2 and MMP-9. Different lengths of peptide and spacers were used in order to determinate the influence of the distance between PS and quencher on the PMB photophysical properties and enzymatic activation.
34

探討Beacon在台灣的創新擴散歷程 - 以燦坤作為創新先鋒為例 / The Study of Implementing Beacon From the Perspective of Innovation Diffusion - A Case Study of Tsann Kuen Enterprise

彭怡翔 Unknown Date (has links)
在行動寬頻、雲端及網際網路等產業的帶動下,全球行動裝置如智慧型手機及平板電腦蓬勃發展,其衍生之行動經濟及應用更為全球經濟成長帶來高度動能。在連網裝置逐年成長之下,物聯網產業應運而生,而其中感測器技術更為物聯網基礎建設中最為核心的關鍵項目。繼蘋果於西元2013年WWDC大會發佈iBeacon技術後,全球零售業掀起微定位熱潮,而Forbes更預估企業利用Beacon搭配APP蒐集消費者資訊為未來物聯網重要趨勢之一。在實體零售店逐漸「展示店化」趨勢下,如何藉由ICT科技、物聯網技術、行動裝置應用來加強與消費者間的連結及提升購物體驗,為實體零售業者急需面對的課題。 本論文研究主要的目的在於探討Beacon於台灣零售業者燦坤的創新擴散歷程,以及使Beacon能夠於燦坤導入每階段快速擴散的關鍵因素,而其中以創新擴散模型之認知、說服、決策、實行、確認五階段構面進行研究與分析。此外,更探討燦坤如何運用Beacon進行O2O虛實整合。 本研究所得到的主要結論包括:(1)在創新擴散的流程中,擁有與導入科技相關的組織團隊背景以及根據創新需求調整組織架構,為Beacon於燦坤之認知階段中能夠快速擴散的關鍵因素。(2)在創新擴散的流程中,鼓勵創新的企業文化為Beacon於燦坤之說服階段中能夠快速擴散的關鍵因素。(3)在創新擴散的流程中,將非核心能力專案外包以及對於外包廠商的選擇,為Beacon於燦坤之決策階段中能夠快速擴散的關鍵因素。(4)在創新擴散的流程中,高階主管對於專案的參與支持以及選擇場域面積、營業額、人流數較大的門市進行首波產品曝光測試,為Beacon於燦坤之實行階段中能夠快速擴散的關鍵因素。(5)在創新擴散的流程中,進行產品的成效評估和顧客滿意度調查,以及尋求產品穩定的獲利模式來源,為Beacon於燦坤之確認階段中能夠快速擴散的關鍵因素。(6)燦坤以Beacon為技術核心打造燦坤黃金傳說APP,以門市尋寶及APP推播的方式,連結燦坤3C實體門市及快3網路商城,使虛實能夠結合及互利。本文最後並提出對於實務上及後續研究的建議。
35

Synthetic Aperture Sonar Micronavigation Using An Active Acoustic Beacon.

Pilbrow, Edward Neil January 2007 (has links)
Synthetic aperture sonar (SAS) technology has rapidly progressed over the past few years with a number of commercial systems emerging. Such systems are typically based on an autonomous underwater vehicle platform containing multiple along-track receivers and an integrated inertial navigation system (INS) with Doppler velocity log aiding. While producing excellent images, blurring due to INS integration errors and medium fluctuations continues to limit long range, long run, image quality. This is particularly relevant in mine hunting, the main application for SAS, where it is critical to survey the greatest possible area in the shortest possible time, regardless of sea conditions. This thesis presents the simulation, design, construction, and sea trial results for a prototype "active beacon" and remote controller unit, to investigate the potential of such a device for estimating SAS platform motion and medium fluctuations. The beacon is deployed by hand in the area of interest and acts as an active point source with real-time data uploading and control performed by radio link. Operation is tightly integrated with the operation of the Acoustics Research Group KiwiSAS towed SAS, producing one-way and two-way time of flight (TOF) data for every ping by detecting the sonar chirps, time-stamping their arrival using a GPS receiver, and replying back at a different acoustic frequency after a fixed time delay. The high SNR of this reply signal, combined with the knowledge that it is produced by a single point source, provides advantages over passive point-like targets for SAS image processing. Stationary accuracies of < 2 mm RMS have been measured at ranges of up to 36m. This high accuracy allowed the beacon to be used in a separate study to characterise the medium fluctuation statistics in Lyttelton Harbour, New Zealand, using an indoor dive pool as a control. Probability density functions were fitted to the data then incorporated in SAS simulations to observe their effect on image quality. Results from recent sea trials in Lyttelton Harbour show the beacon TOF data, when used in a narrowband motion compensation (MOCOMP) process, provided improvements to the quality of SAS images centred on frequencies of 30 kHz and 100 kHz. This prototype uses simple matched-filtering algorithms for detection and while performing well under stationary conditions, the fluctuations caused by the narrow sonar transmit beam pattern (BP) and changing superposition of seabed multipath often cause dropouts and inaccurate detections during sea trials. An analysis of the BP effects and how the accuracy and robustness of the detection algorithms can be improved is presented. Overcoming these problems reliably is difficult without dedicated large scale testing facilities to allow conditions to be reproduced consistently.
36

Synthèse de systèmes à base de photosensibilisateurs pour l'amélioration de la sélectivité tumorale en thérapie photodynamique / Synthesis of new systems based on photosensitizers for the improvement of the tumor selectivity in photodynamic therapy

Stallivieri, Aurélie 16 October 2015 (has links)
Une des limitations de la thérapie photodynamique est la faible sélectivité des photosensibilisateurs (PS) pour les tissus tumoraux. La recherche de nouveaux PS plus sélectifs s’est orientée vers la synthèse de PS couplés à des motifs afins pour des récepteurs membranaires surexprimés dans certains cancers. Le récepteur à l’acide folique est surexprimé dans les carcinomes ovariens et des PS ont été conjugués à de l’acide folique. Des PS ont aussi été couplés à un peptide spécifique de neuropiline 1 surexprimé au niveau des cellules tumorales de médulloblastome. Une autre stratégie pour augmenter la sélectivité du traitement vise à produire les espèces réactives de l’oxygène spécifiquement au niveau du site tumoral. L’activité de clivage enzymatique de marqueurs biologiques surexprimés dans les zones tumorales est utilisée. Les gélatinases (MMP-2 et -9) et leur activateur MMP-14 sont connues pour jouer un rôle primordial dans l'angiogenèse tumorale et la croissance du glioblastome multiforme. Différents photodynamic molecular beacons (PMB), associant un PS et un quencher lié par un peptide substrat des gélatinases et MMP-14, ont été développés / One limitation of photodynamic therapy is the low selectivity of photosensitizers (PS) to tumour tissue. The search of new PS more selective began to focus on the synthesis of PS coupled with substrate specific of the membrane receptors overexpressed in certain cancers. The acid folic receptor is overexpressed in ovarian carcinomas and PS were conjugated with folic acid. PS were also coupled with a specific peptide of neuropilin 1 overexpressed in tumoral cells of medulloblastoma. Another strategy for increasing the selectivity of the treatment is to produce reactive oxygen species specifically at the tumor site. The activity of enzymatic cleavage of biomarkers overexpressed in tumour areas is used. The gelatinases (MMP-2 and MMP-9) and their activator MMP-14 are known to play a key role in tumour angiogenesis and the growth of glioblastoma multiform. Different photodynamic molecular beacons (PMB), composed of a photosensitizer and a quencher linked together by a peptide substrate of gelatinases or MMP-14, were designed.
37

Effectiveness of a Pedestrian Hybrid Beacon at mid-block pedestrian crossings in decreasing unnecessary delay to drivers and a comparison to other systems

Godavarthy, Ranjit Prasad January 1900 (has links)
Master of Science / Department of Civil Engineering / Eugene R. Russell / Pedestrian signals, particularly at signalized, mid-block crossing can cause delay to drivers after pedestrians’ have successfully crossed, which is termed “unnecessary delay” in this study. In many cases at a mid-block signal, a pedestrian pushes the button and then quickly crosses the street as soon as the walk signal appears and drivers still face several seconds of solid red ball and by law must remain stopped. On a busy street, a queue of vehicles waiting after all pedestrians have crossed can amount to hundreds of hours of unnecessary delay per year. The ‘Pedestrian Hybrid Beacon’ (Initially named a HAWK (High Intensity Activated Crosswalk)) Beacon was proven to be effective in decreasing this unnecessary delay when compared to standard signalized mid-blocks. The City of Lawrence, Kansas was interested in experimenting (as a HAWK beacon was considered experimental when they were installed) with a pedestrian hybrid beacon and they installed their first pedestrian hybrid beacon at a mid-block crossing on 11th street and a second pedestrian hybrid beacon at mid-block crossing on New Hampshire street, Lawrence, Kansas, which were the sites of interest for this research. A study was conducted at these sites to determine the effectiveness of the pedestrian hybrid beacon in decreasing the unnecessary delay to drivers by comparing it to a signalized mid-block crossing on Massachusetts Ave in Lawrence, Kansas. Apart from the delay measurements for these two sites, other parameters such as driver compliance rate to the signal, pedestrian compliance rate, and other driver and pedestrian characteristics were also studied. Video cameras were used to capture video at these sites and the effectiveness of the pedestrian hybrid beacon was analyzed from the video. The HAWK, now in the MUTCD as a Pedestrian Hybrid Beacon, proved to be effective in decreasing the unnecessary delay for drivers in this study. The City of Lawrence had a total of six pedestrian hybrid beacons in operation as per the information received in March 2010.
38

AIRSPACE UTILIZATION REPORTING SYSTEM FOR THE R-2508 COMPLEX

Ward, John M. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Increasingly, military managers are requiring better and more efficient use of Special Use Airspace (SUA) and Military Operating Areas (MOA). To date, there has been no automated method for determining airspace utilization within the R-2508 Complex. This paper describes the development of a computer based airspace management tool called Airspace Utilization Reporting System (AURS). AURS receives aircraft beacon radar data from an air traffic control automation system used within the R-2508 Complex. The system processes this data in a customized Oracle database format and responds to query requests, making any information about aircraft activities and airspace utilization available to the user. AURS operates continuously 24 hours per day, seven days per week. The system provides a tool for near complete analysis of all transponder equipped aircraft activities and utilization information within the 20,000 square miles R-2508 airspace Complex. In this paper we also provide detailed AURS reports and examples of military and civilian aircraft activities obtained with AURS.
39

Inertial Navigation Sytem Improvement Using Ground Station Data

Guner, Dunya Rauf Levent 01 September 2012 (has links) (PDF)
Missile navigation systems rely on hybrid INS/GPS systems to employ lower grade inertial sensors for the sake of cost and availability. Current inertial navigation systems on missiles can perform accurately for a limited time without GPS aiding. However, GPS is the most likely system that is going to be jammed in a crisis or war by low cost jammers by any opposing force. Missiles do not have adequate equipment to maintain accuracy when GPS is jammed completely in the battle area. In this thesis, a new method is proposed to improve performance of INS systems onboard missiles and autonomous aerial vehicles with EO sensors in a GPS denied environment. Previously laid ground based beacons are used by the missile EO/IIR seeker for bearing-only measurements and position updates are performed by the use of modified artillery survey algorithms based on triangulation techniques which involve angle measurements. For mission planning, two main problems are identified as deployment problem and path planning problem and a tool for the optimal laying of beacons for a given desired trajectory and optimal path planning for a given network of beacons is developed by using evolutionary algorithms and results for test scenarios are discussed.
40

Böten, Signalen och Branden : Att undersöka förutsättningarna för signalsystem med hjälp av GIS och ortnamn / The Beacon, the Signal and the Fire : To explore the conditions of signal systems using GIS and placenames

Palmborn, Markus January 2018 (has links)
Scandinavia is famous for their Viking ships and their raids during the 9th century. However, the Scandinavian society was widely divided between the ruling forces. There are a lot of evidence for conflicts within the Viking world, with both written sources, stories and archaeological records speaking for it. As the ship, and travel by water, was one of the most efficient ways of travelling, widely used within all of Iron Age Scandinavia, this paper seeks to explore the possibilities of a maritime defense system within the central Viking society using place names and GIS. Uppland, as one of the most influential areas in Scandinavian Iron Age, hosting sites as Vendel and Gamla Uppsala, the use and need of a maritime defense would have been, due to the risk of conflict, vital.

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