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Adapting Fourier Analysis for Predicting Earth, Mars and Lunar Orbiting Satellite's Telemetry BehaviorLosik, Len 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Prognostic technology uses a series of algorithms, combined forms a prognostic-based inference engine (PBIE) for the identification of deterministic behavior embedded in completely normal appearing telemetry from fully functional equipment. The algorithms used to define normal behavior in the PBIE from which deterministic behavior is identified can be adapted to quantify normal spacecraft telemetry behavior while in orbit about a moon or planet or during interplanetary travel. Time-series analog engineering data (telemetry) from orbiting satellites and interplanetary spacecraft are defined by harmonic and non-harmonic influences, which shape it behavior. Spectrum analysis can be used to understand and quantify the fundamental behavior of spacecraft analog telemetry and relate the behavior's frequency and phase to its time-series behavior through Fourier analysis.
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The in-service determination of the presence of distortion in a high quality analogue sound signalMare, Stefanus January 2007 (has links)
Thesis (D.Tech.: Electronic Engineering)-Dept. of Electronic Engineering, Durban University of Technology, 2007
vii, 150 leaves / Detecting and minimising distortion in audio signals is an important aspect of sound engineering. Distortion of a signal passing through an audio system may be caused by a number of factors and it is necessary to detect these effects for optimal sound. The problem is of interest to users and operators of high quality audio equipment and transmission facilities.
The objective of this thesis was the development of techniques for the blind identification of distortion in a high quality audio signal using digital signal processing techniques. The techniques developed are based on digital signal processing techniques and statistical analysis of a recorded audio signal, which is treated as a random, non-stationary signal.
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Using Telemetry Science, An Adaptation of Prognostic Algorithms for Predicting Normal Space Vehicle Telemetry Behavior from Space for Earth and Lunar Satellites and Interplanetary SpacecraftLosik, Len 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Prognostic technology uses a series of algorithms, combined forms a prognostic-based inference engine (PBIE) for the identification of deterministic behavior embedded in completely normal appearing telemetry from fully functional equipment. The algorithms used to define normal behavior in the PBIE from which deterministic behavior is identified can be adapted to quantify normal spacecraft telemetry behavior while in orbit about a moon or planet or during interplanetary travel. Time-series analog engineering data (telemetry) from orbiting satellites and interplanetary spacecraft are defined by harmonic and non-harmonic influences which shape it behavior. Spectrum analysis can be used to understand and quantify the fundamental behavior of spacecraft analog telemetry and relate the behavior's frequency and phase to its time-series behavior through Fourier analysis.
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探討B2B電子商務平台信號與買方行為之關係 / Investigating the effects of online signals on buyers behavior魏君 Unknown Date (has links)
近年來,電子商務飛速發展,已取得長足進步。電子商務可以高效利用有限資源,加快商業週期循環,節省時間、降低成本、提高利潤和增強企業競爭力,並以傳統經營方式所無法比擬的優點受到全球關注。因此,電子商務給企業所帶來的影響是非常重要且值得探討。
在電子商務貿易模式中,信息的高效傳遞成為平台上賣方增強競爭力的重要手段。但是過去鮮少有研究以信號理論觀點,切入探討B2B交易平台上賣方信號對買方之吸引力,以及鮮少有研究探討其中是否有其他變數可能會增加或削弱兩者之間的關係。因此本研究旨在探討賣方採用的信號與買方聯繫賣方之可能性的關係,並以企業外部市場化發展程度因素作為干擾變數。
本文共蒐集167家中小企業信息作為研究對象,並以階層回歸作為分析方法,進一步釐清賣方所採用的信號與買方聯繫賣方之可能性之間的關係,並以企業外部市場化發展程度作為干擾變數,研究外部環境情況是否會強化賣方所採用的信號與買方聯繫賣方之可能性之間的關係,補充過去文獻鮮少探討之觀點。冀望本研究結果能為平台賣方之決策者在考慮如何運營,提供一些參考與建議。
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Nachweis von Mikroemboliesignalen mittels transkraniellem Dopplerultraschall nach Stentimplantation der Arteria carotis internaZerweck, Christof 09 February 2016 (has links) (PDF)
Hintergrund: Das Auftreten von frühen postinterventionellen Komplikationen nach Stenting der Arteria carotis interna (ACI) wird auf die Embolisierung von Material aus dem Stentsegment zurückgeführt. Zerebrale Thrombembolien können nicht invasiv mittels transkraniellem Dopplerultraschall (TCD) als mikroembolische Signale (MES) detektiert werden.
Studienziel : Die Studie wurde durchgeführt um Prädiktoren zu finden, welche eine hohe Anzahl von MES im Intervall einer Stunde nach dem Eingriff voraussagen könnten.
Methodik: Bei 134 konsekutiven Patienten, die ein Stenting der ACI erhielten, wurde postinterventionell über eine Stunde eine TCD der ipsilateralen Arteria cerebri media durchgeführt. Zur Identifizierung von klinischen, morphologischen und prozedurabhängigen Parametern für vermehrte MES, wurde eine multivariate logische Regressionsanalyse durchgeführt.
Ergebnisse: Bei 134 Patienten (111 männlich, 23 weiblich, mittleres Alter 69,7 Jahre) wurden in 38% MES detektiert (Mittelwert 4 MES/h; Streuung von 1-62MES/h). Zwei Variablen waren mit einer erhöhten postinterventionellen MES Rate vergesellschaftet. Diese waren: Symptomatische Läsionen (p=0,048) und erhöhtes Gesamtcholesterin (p=0,037). Die duale Thrombozytenaggregationshemmung (ASS und Clopidogrel) konnte als unabhängiger Prädiktor (p=0,0001) für eine erniedrigte MES Rate festgestellt werden.
Schlussfolgerungen: Postinterventionelle MES konnten am häufigsten bei symptomatischen Läsionen und bei Patienten mit Hypercholesterinämie festgestellt werden. Deren Anzahl viel im Verlauf ab. Das Stentdesign hatte keinen Einfluss auf die Anzahl der gemessenen MES. Die Kombinationstherapie mit ASS und Clopidogrel war ein Prediktor für eine erniedrigte cerebrale Embolisationsrate. Die TCD der MES Rate könnte eine brauchbare Methode sein um mögliche Risikofaktoren für neurologische Komplikationen nach Stenting der ACI zu entdecken und somit die Sicherheit der Stentingprozedur der ACI zu verbessern.
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The development and implementation of a localised position location strategySchonken, Willem Petrus Francois 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Location and tracking of personnel and assets is a lucrative enterprise that has seen much expansion in
the last decade or two. This expansion is coupled with the rise in popularity of GPS-based technologies.
It has become common practice for businesses to track and manage vehicle fleets with GPS enabled
devices. We use GPS to navigate while driving our cars, to keep track of our loved ones and we even
have GPS receivers in our cell phones.
Unfortunately, GPS technology has a few limitations. It can only be used in areas with a clear view of the
sky, as line-of-sight must be maintained with at least four satellites at all times. This precludes the use of
GPS indoors or in heavily built-up areas. GPS receivers are also still quite expensive.
This thesis developed and implemented a strategy for Localised Position Location. Several possible
solutions were investigated. Spread Spectrum was selected as the best method to develop into a
working example. The characteristics of Spread Spectrum signals and Pseudo-Noise Codes were
investigated in some detail, which led to the proposal of several simulation models. These simulations
suggested that a simple configuration consisting of a transmitter, sliding correlator, bandpass filter and
RF power detector can effectively track a stationary target.
A transmitter was designed and implemented and was then used in a simplified measurement to
corroborate the predictions made by earlier simulations. With results looking positive it was decided to
continue with the design and implementation of a receiver. A complete transmitter/receiver system
allowed for extensive measurements to be made. The physical measurements agreed with simulated
predictions, confirming that the proposed position location strategy is effective. / AFRIKAANSE OPSOMMING: Die toenemende gewildheid en toeganklikheid van GPS-gebaseerde opsporingstegnologie het gelei tot
‘n geweldige toename in die verkope van toerusting om die beweging van besigheidsbates te monitor en
bestuur. Selfs op die persoonlike ontspanningsmark vind GPS-tegnologie toenemend aanklank met
vervaardigers van selfone en voertuignavigasietoerusting.
GPS-gebaseerde opsporingstegnologie het egter beperkinge, omdat dit te alle tye direkte oogkontak
moet behou met minstens vier satelliete. Gevolglik kan GPS-gebaseerde opsporingstegnologie nie
binnenshuis of in erg beboude gebiede gebruik word nie. GPS ontvangers is ook redelik duur.
Hierdie thesis het `n strategie vir Gelokaliseerde Posisie Bepaling ontwikkel en geïmplementeer.
Ondersoek is ingestel na `n verskeidenheid van moontlike oplossings. Strek Spektrum is gekies as die
beste metode om verder in `n werkende voorbeeld te ontwikkel. Die eienskappe van Strek Spektrum
seine en Pseudo-Ruis Kodes is in detail bestudeer, wat gelei het na die opstelling van `n aantal simulasie
modelle. Hierdie modelle dui aan dat `n eenvoudige opstelling, bestaande uit `n sender, glykorellator,
banddeurlaat filter en `n RF drywingsmeter doeltreffend aangewend kan word om `n stilstaande teiken
te monitor.
`n Sender, wat in `n vereenvoudigde meetopstelling gebruik kon word om van die voorspellings wat
vroeër gemaak is te staaf, is hierna ontwerp en gebou. Met positiewe resultate is daar besluit om voort
te gaan met die ontwerp en bou van `n ontvanger. Met `n volledige sender/onvanger stelsel was dit
moontlik om uitgebreide meetings te neem. Die fisiese meetings stem ooreen met die simulasies se
voorspellings, wat dien as bevestiging dat die voorgestelde strategie vir posisie bepaling doeltreffend
aangewend kan word.
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Adapting Fourier Analysis for Predicting Earth, Mars and Lunar Orbiting Satellite's Telemetry BehaviorLosik, Len 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Prognostic technology uses a series of algorithms, combined forms a prognostic-based inference engine (PBIE) for the identification of deterministic behavior embedded in completely normal appearing telemetry from fully functional equipment. The algorithms used to define normal behavior in the PBIE from which deterministic behavior is identified can be adapted to quantify normal spacecraft telemetry behavior while in orbit about a moon or planet or during interplanetary travel. Time-series analog engineering data (telemetry) from orbiting satellites and interplanetary spacecraft are defined by harmonic and non-harmonic influences, which shape it behavior. Spectrum analysis can be used to understand and quantify the fundamental behavior of spacecraft analog telemetry and relate the behavior's frequency and phase to its time-series behavior through Fourier analysis.
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Mining Topic Signals from TextAl-Halimi, Reem Khalil January 2003 (has links)
This work aims at studying the effect of word position in text on understanding and tracking the content of written text. In this thesis we present two uses of word position in text: topic word selectors and topic flow signals. The topic word selectors identify important words, called <i>topic words</i>, by their spread through a text. The underlying assumption here is that words that repeat across the text are likely to be more relevant to the main topic of the text than ones that are concentrated in small segments. Our experiments show that manually selected keywords correspond more closely to topic words extracted using these selectors than to words chosen using more traditional indexing techniques. This correspondence indicates that topic words identify the topical content of the documents more than words selected using the traditional indexing measures that do not utilize word position in text.
The second approach to applying word position is through <i>topic flow signals</i>. In this representation, words are replaced by the topics to which they refer. The flow of any one topic can then be traced throughout the document and viewed as a signal that rises when a word relevant to the topic is used and falls when an irrelevant word occurs. To reflect the flow of the topic in larger segments of text we use a simple smoothing technique. The resulting smoothed signals are shown to be correlated to the ideal topic flow signals for the same document.
Finally, we characterize documents using the importance of their topic words and the spread of these words in the document. When incorporated into a Support Vector Machine classifier, this representation is shown to drastically reduce the vocabulary size and improve the classifier's performance compared to the traditional word-based, vector space representation.
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Effet des actions pédagogiques sur l'état émotionnel de l'apprenant dans un système tutoriel intelligentBenadada, Khadija January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
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Exploring the project management community paradigm and the role of performance predictionHalliburton, Richard January 2014 (has links)
‘Project performance’ is the metric of delivering project objectives. This research is motivated by levels of project failure and the purpose of the research is to investigate improved project performance. The scientific spectrum is considered; arguing project management as a sub-field of management science based in ‘design science’. Despite research since the 1950s, there is no established community paradigm for project management, illustrated by multiple ‘schools of thought’ failing to stimulate performance improvement. This is investigated with respect to the changing nature of projects and their management; application in numerous industrial sectors, across increasing scope of the product lifecycle (including service projects), and the changing role of project managers as value adding ‘implementers’ rather than status ‘reporters’. Methodology examines the community paradigm and identifies the lack of community paradigm and argues that gap spotting is not appropriate. Conducting research that fills knowledge gaps does not identify underlying issues and reinforces fundamental failings. Underlying assumptions are identified and challenged. Key characteristics are examined in the context of requirements of the community paradigm. The purpose of theory is to describe, explain and predict. Some techniques describe and explain. Few, if any, predict. This locates ‘performance prediction’ as the research issue and suggests it is a missing function for performance improvement. The research focus considers single tasks within a project network. A research model of early stage deviation from plan is developed from the literature on project pathogens and incubation processes. ‘Deviation lifecycle’ as a project function is identified as having no previous evidence in literature. This is developed into a practice model extending the role of failure modes and effects analysis (FMEA) and integrating weak signals and tipping point theory to test performance. Case studies examine representative application of the model and build on the previous cases to illustrate potential for practice. The case studies were reviewed by industrial experts. The changing role of project managers to value added implementers implies a need to improve performance. Research found potential to understand and predict early stage deviation and develops the deviation lifecycle and research model. Across the case studies the research model illustrated potential application. Practical implications indicate potential contribution of project management techniques based on prediction rather than traditional reporting. Developing the community paradigm based on design science is discussed as further work. The originality of the research challenges the lack of theoretical foundation for project management by discussion of the community paradigm and proposes design science as a candidate. The work identifies ‘prediction’ as a relevant but missing function from the project management ‘toolbox’, and introduces the concept of the deviation lifecycle and note no previous literature. The research develops an industrial research model that extends the application of FMEA to examine ‘performance’ and integrates weak signals and tipping point analysis to manage the resolution.
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