Traditionally, surface topography measurement was in the domain of quality control of engineering parts. With the advancement of manufacturing technology and affordable computational costs, different types of surfaces are produced with varied shapes and surface textures. These pose significant measurement problems, therefore, surface topography research is gaining momentum to achieve a better control of the surface. Coherence scanning interferometry (CSI) is one of the most common techniques used for measurement of surface topography. It is preferred over tactile and other non-contact techniques since it provides fast and accurate measurement with high vertical (~ 1 nm) and lateral (~1 μm) resolutions over larger areas without any damage to the surface. Essentially, CSI is treated as one dimensional (1D) superposition of the light waves from an object and a reference that generates a three dimensional (3D) interferogram. Secondly, despite the advantages, there is no standard configuration of CSI that can provide absolute surface topography measurement of an engineering part with multiple materials. An effective solution to this problem will be particularly useful in the field of semiconductor and bio-related industries where chips and instruments are made of many materials. In this Thesis, first, the CSI technique is analysed in terms of a wider theoretical framework of 3D linear filtering technique which shows the similarities among other seemingly disparate techniques such as confocal and optical coherence tomography. Due consideration to the spectral characteristic of the source and the effect of numerical aperture are given and important parameters such as vertical and lateral resolutions are computed to compare this theory with standard analysis methods. Additionally, it is shown that the 3D fringe pattern can be considered to be a superposition of a reference field and the scattered field from the top foil-like layer on the top the object. The scattered field from this foil object is dependent on the normal Fresnel reflection coefficients. Therefore, it explains the phase offset and the proportional height offset introduced by different materials, especially, metals. In an object, where multiple materials are present, each material introduces different phase to the fringe pattern and therefore, the surface topography of the entire object is altered. To overcome this problem, the optical polarising properties of the material are exploited. A novel configuration of polarisation sensitive CSI is presented where interferograms with orthogonal circular polarisations are recorded and analysed. The configuration, initially, needs to be calibrated with a material and after that at each point on the object, the refractive index and height offset can be calculated. Therefore, it can be dually used to identify unknown materials present on the object and also to compensate for the height offset introduced by each material to produce absolute surface topography of the entire object. The configuration provides good agreement with ellipsometric results for metals. Additionally, it retains the advantages of high vertical and lateral resolution same as other standard coherence scanning interferometers.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Several different kinds of signal are transmitted through only one carrier in microwave unified telemetry tracking & control system(MUTTCS), which has replaced separate system to accomplish all TT&C functions, and has been widely used now. This paper analyses the advantages and disadvantages of general subcarrier frequency-division MUTTCS, then the principle and performances of advanced spread spectrum MUTTCS(SS-MUTTCS) are discussed in detail. The inherent ranging ability of PN code and the speciality of spread spectrum modulation realize the complete unification including measurement of range, velocity and angle as well as telemetry, telecontrol and communication functions. At the same time, the contradiction between range and velocity measurement in precision, resolution and measuring range can be solved. With CDMA technology, the signal and equipment of multi-target or multi-station TT&C can be unified easily. SS-MUTTCS operates under low S/N, low threshold, low power spectrum density and wide spectrum range, so it meet the requirements of electronic warfare and ECM, with high performance of safety, security, anti-intercept and anti-interference. Therefore, SSMUTTCS is becoming an important trend of modern vehicle TT&C system.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During engine and airfield performance testing it is often necessary to acquire weather data at the airfield where the test is being conducted. The airborne data acquisition system (DAS) acquires data associated with flight parameters. A separate system records airport weather conditions. Many times the separate system is an Automated Terminal Information Service (ATIS) or the ground crew relaying wind speed, wind direction and temperature from a weather station. To improve this system, the weather station is designed to acquire and store the data in memory. Utilizing a second DAS that is remote to the airborne DAS poses several problems. First, it is undesirable to have many different data acquisition systems from which to process data. The problem then develops into one of integrating the ground weather DAS with the existing airborne DAS. Other problems of system integrity, compatibility and FCC licensing exist. Complete system integration while maintaining integrity and compatibility is overcome by controlling signal format, flow and timing and is discussed in detail. Further discussion of the issue of transmission is overcome by a technique called spread-spectrum and is used in accordance with FCC rules and regulations.

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.

投資高報酬的背後往往隱含著高風險，尤以選擇權投資最為明顯，在高槓桿的誘因背後，也同時具有複雜性高的操作難度，因此為達到不同風險及報酬的抵換效果，各種選擇權交易策略因此應運而生。其基本觀念為：透過不同選擇權基本策略(Building Block)的組合，來配合不同的市況預測，以達到投資人最適的損益特徵。 　　選擇權交易策略一般分為基本部位、價差部位、混合部位、合成部位及避險部位，其中由於交易條件與交易成本的限制，一般投資人多使用前三種選擇權策略進行交易，然而，對於初入市的投資人而言，常侷限於策略的組合方式，反而忽略風險與報酬的本質，因此於選擇權的投資往往導致損失。 　　本研究以台指選擇權為例，旨在討論選擇權三種常用策略之市場實證，透過固定進場時點的設定、履約價格的調整以及持有至結算日的原則，來計算不同策略於2003~2005年之投資績效。並討論三種策略在獲勝率、到期損益、報酬率及報酬變異情形。 　　整體而言，從事基本策略的買方，不論是買進買權或買進賣權，在各個履約價格的獲勝機率均極小，也同時顯示從事基本策略的賣方仍然在台指選擇權市場中佔有優勢。價差策略的買方勝率亦遠小於賣方。混合策略中的賣出勒式策略則顯示極優的獲勝機率及累積績效，本策略也是一般期貨自營商或機構法人常用的策略。 　　本研究之結論可作為投資者建構選擇權策略組合之參考，透過定時定價的進場能提高獲勝機率，更能貼近台指選擇權市場實際情況，獲取更好的利潤。

殖利率曲線為描述零息債卷的殖利率與其到期日間之關係，一般來說其形狀應為正斜率，而一旦殖利率曲線反轉而呈現負斜率時，許多人將之解讀為未來經濟即將走弱的訊號。本論文主要是以Probit Model呈現期間利差與重貼現率的預測能力，並將結果區分為樣本內與樣本外呈現。實證結果發現，與國外文獻比較起來，台灣殖利率曲線斜率捕捉景氣蕭條的能力遜色許多，可能與兩國在經濟體質或是央行政策執行依據上的不同有關。而相較於殖利率曲線的斜率，重貼現率對於台灣景氣的影響更為明顯，顯示出台灣的經濟深受央行政策影響。而不論是在樣本內或樣本外的結果方面，皆顯示期間利差搭配重貼現率的預測能力會較只有期間利差單一解釋變數時來的好。

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.

The first chapter of this dissertation estimates the relative contributions of two major exchanges on crude oil futures to the price discovery process-- Chicago Mercantile Exchange (CME) and Intercontinental Exchange (ICE), using trade-by-trade data in 2008. The study also empirically analyzes the effects of trading characteristics on the information share of these two markets. Trading characteristics examined in the study include trading volume, trade size, and trading costs. On average, CME is characterized by greater volume and trade size but also slightly greater bid-ask spread. CME leads the process of price discovery and this leadership is caused by relative trade size and volatility before the financial crisis of 2008; however post-crisis period this leadership is caused by trading volume. Moreover, this study presents evidence that, in times of large uncertainty in the market, the market maker charges a greater bid-ask spread for the more informative market. The second chapter examines the influence of expected oil price volatility, the behavior of the Organization of Petroleum Exporting Countries (OPEC), and the US Dollar exchange rate volatility on the backwardation of crude oil futures during the period from January 1986 to December 2008. The results indicate that oil futures are strongly and weakly backwardated 57% and 69% of the time, respectively. The regression analysis of weak backwardation shows that oil volatility, OPEC overproduction (difference between quota and the actual production), and the volatility of the US Dollar against the Japanese Yen have a positive significant effect on oil backwardation, while OPEC production quota imposed on its members has a negative significant effect on oil backwardation. However the volatility of US Dollar against the British Pound has no significant effect on oil backwardation. The regression analysis of strong backwardation produces qualitatively the same results except that volatility has no effect. In a sub-period analysis, evidence also indicates that trading volume of oil funds and backwardation are negatively related, suggesting that oil funds increase the demand of futures relative to that of spot.

The spread between interest rate and sovereign bond rate is commonly used in- dicator for country's probability to default. Existing literature proposes many different potential spread determinants but fails to agree on which of them are important. As a result, there is a considerable uncertainty about the cor- rect model explaining the spread. We address this uncertainty by employing Bayesian Model Averaging method (BMA). The BMA technique attempts to consider all the possible combinations of variables and averages them using a model fit measure as weights. For this empirical exercise, we consider 20 different explanatory variables for a panel of 47 countries for the 1980-2010 period. Most of the previously suggested determinants were attributed high inclusion probabilities. Only the "foreign exchange reserves growth" and the "exports growth" scored low by their inclusion probabilities. We also find a role of variables previously not included in the literature's spread determinants - "openness" and "unemployment" which rank high by the inclusion probability. These results are robust to a wide range of both parameter and model priors. JEL Classification C6, C8, C11, C51, E43 Keywords Sovereign Spread Determinants, Model Uncer- tainty, Bayesian Model Averaging Author's e-mail semanv()gmail()com...

When processing materials, there are a number of factors which influence the final quality of products. The possibility of defects occurrence, both sub-surface and surface ones, is one of the factors. In the precision engineering production, the automotive, bearing or aerospace industry in particular, no level of defects is tolerable. The thesis deals with the causes and consequences of the occurrence of such defects, and the methods for their identification. For this purpose, a new contactless optical method for the fully automatic inspection of the surface defects has been developed by Mesing, spol. s r.o. In order to verify the performance of the aforementioned method, four specific products have been tested by the author using the method. Finally, there are examples of the successful implementation of the automatic machines, for a design of which the results of the model testing were utilized.