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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.
161

Asian Spread Option Pricing Models and Computation

Chen, Sijin 10 February 2010 (has links) (PDF)
In the commodity and energy markets, there are two kinds of risk that traders and analysts are concerned a lot about: multiple underlying risk and average price risk. Spread options, swaps and swaptions are widely used to hedge multiple underlying risks and Asian (average price) options can deal with average price risk. But when those two risks are combined together, then we need to consider Asian spread options and Asian-European spread options for hedging purposes. For an Asian or Asian-European spread call option, its payoff depends on the difference of two underlyings' average price or of one average price and one final (at expiration) price. Asian and Asian-European spread option pricing is challenging work. Even under the basic assumption that each underlying price follows a log-normal distribution, the average price does not have a distribution with a simple form. In this dissertation, for the first time, a systematic analysis of Asian spread option and Asian-European spread option pricing is proposed, several original approaches for the Black-Scholes-Merton model and a special stochastic volatility model are developed and some numerical computation tests are conducted as well.
162

Root Mean Square-Delay Spread Characteristics for Outdoor to Indoor Wireless Channels in the 5 GHz Band

Kurri, Prasada Reddy 26 July 2011 (has links)
No description available.
163

Är gräset grönare på andra sidan? : En jämförande studie mellan gröna och konventionella obligationer ur ett investerarperspektiv

Jackson-Peters, Elias, Jakobsson, Johanna January 2022 (has links)
Obligationer är grundläggande för kapitalmarknadens funktion, och på senare tid kräver investerare möjligheten att diversifiera sina portföljer utefter miljömässiga och klimatfrämjande ändamål. Gröna obligationer omfattas av osäkerheter som exempelvis risker för greenwashing och obefintlig reglerad tillsyn över det öronmärkta kapitalet. Gröna certifieringar sägs motverka dessa risker och integreras därför i studien. Sedan gröna företagsobligationer introducerades på marknaden har det även florerat rykten om att investerare avstår en del av sin avkastning för att investera enligt sina gröna preferenser. Den gröna premien har undersökts i många utföranden, men alltför sällan på den svenska primärmarknaden. Studien använder sig av en matchningsmetod tillsammans med en hypotesprövning och korrelationsanalyser för att undersöka förekomsten av en grön premie. Matchningsparen består av likvärdiga gröna och konventionella företagsobligationer. Resultaten visar att det förekommer en svagt positiv premie för gröna obligationer och att gröna certifieringar har en stor betydelse för fortsatt marknadseffektivitet och minskad informationsasymmetri. Slutsatsen blir därmed att gröna företagsobligationer emitterade av svenska fastighetsföretag inte nämnvärt lönar sig ekonomiskt, men kommer med andra fördelar såsom en riskdiversifierad investeringsportfölj. / Bonds are fundamental to the functioning of the capital market, and more recently investors have been seeking the possibility to diversify their portfolios by making more environmental and climate conscious investments. Green bonds are accompanied by uncertainties, for example risk of greenwashing and insufficient regulations and supervision of the earmarked capital. Green certification has the possibility of minimising these risks and has therefore been integrated into this study. Since green certification has been introduced into the market, rumour has it that investing in green bonds results in losing part of one's profit margin. The green premium has been examined in many ways, but all too rarely in the Swedish primary market. To investigate if a green premium exists the study uses a matching method, together with a hypothesis test and correlation analysis. The matching method consists of equal parts of green and conventional corporate bonds.  The results show a slightly more positive premium of green bonds, and that green certification is both meaningful and important for continued market efficiency and reduced information asymmetry. The conclusion is therefore that green corporate bonds issued by Swedish real estate companies are not financially advantageous but do bring other benefits such as a risk-diversified investment portfolio.
164

Contribution to fluorescence microscopy, 3D thick samples deconvolution and depth-variant PSF / Contribution à la microscopie de fluorescence, Deconvolution des échantillons épais avec PSF variables en profondeur

Maalouf, Elie 20 December 2010 (has links)
La reconstruction 3D par coupes sériées en microscopie optique est un moyen efficace pour étudier des spécimens biologiques fluorescents. Dans un tel système, la formation d'une image peut être représentée comme une convolution linéaire d'un objet avec une réponse impulsionnelle optique de l'instrument (PSF). Pour une étude quantitative, une estimation de l'objet doit être calculée en utilisant la déconvolution qui est le phénomène inverse de la convolution. Plusieurs algorithmes de déconvolution ont été développés en se basant sur des modèles statistiques ou par inversion directe, mais ces algorithmes se basent sur la supposition de l'invariance spatiale de la PSF pour simplifier et accélérer le processus. Dans certaines configurations optiques la PSF 3D change significativement en profondeur et ignorer ces changements implique des erreurs quantitatives dans l'estimation. Nous proposons un algorithme (EMMA) qui se base sur une hypothèse où l'erreur minimale sur l'estimation par un algorithme ne tenant pas compte de la non-invariance, se situe aux alentours de la position (profondeur) de la PSF utilisée. EMMA utilise des PSF à différentes positions et fusionne les différentes estimations en utilisant des masques d'interpolation linéaires adaptatifs aux positions des PSF utilisées. Pour obtenir des PSF à différentes profondeurs, un algorithme d'interpolation de PSF a également été développé. La méthode consiste à décomposer les PSF mesurées en utilisant les moments de Zernike pseudo-3D, puis les variations de chaque moment sont approximés par une fonction polynomiale. Ces fonctions polynomiales sont utilisées pour interpoler des PSF aux profondeurs voulues. / The 3-D fluorescence microscope has become the method of choice in biological sciences for living cells study. However, the data acquired with conventional3-D fluorescence microscopy are not quantitatively significant because of distortions induced by the optical acquisition process. Reliable measurements need the correction of theses distortions. Knowing the instrument impulse response, also known as the PSF, one can consider the backward process of convolution induced by the microscope, known as "deconvolution". However, when the system response is not invariant in the observation field, the classical algorithms can introduce large errors in the results. In this thesis we propose a new approach, which can be easily adapted to any classical deconvolution algorithm, direct or iterative, for bypassing the non-invariance PSF problem, without any modification to the later. Based on the hypothesis that the minimal error in a restored image using non-invariance assumption is located near the used PSF position, the EMMA (Evolutive Merging Masks Algorithm) blends multiple deconvolutions in the invariance assumption using a specific merging mask set. In order to obtain sufficient number of measured PSF at various depths for a better restoration using EMMA (or any other depth-variant deconvolution algorithm) we propose a 3D PSF interpolation algorithm based on the image moments theory using Zernike polynomials as decomposition base. The known PSF are decomposed into Zernike moments set and each moment's variation is fitted into a polynomial function, the resulting functions are then used to interpolate the needed PSF's Zernike moments set to reconstruct the interpolated PSF.
165

Tracer gas mapping of beverage cart wake in a twin aisle aircraft cabin simulation chamber

Trupka, Andrew Tristan January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / Mohammad H. Hosni / Byron W. Jones / In 2010, over 786 million passengers flew on commercial flights in the United States according to the Bureau of Transportation Statistics (2011). With the average flight length over 1300 miles for domestic flights, this amounts to billions of hours spent aboard airliners by passengers each year. During these flights, diseases and other harmful contaminates, some malicious, can spread throughout aircraft cabins, harming passengers. Aircraft ventilation systems are designed to remove these harmful contaminates as quickly as possible to minimize spread in cabin air. Disruptions to the design airflow pattern can hinder the effectiveness of contamination removal efforts. A common form of this airflow disruption is longitudinal air movement through cabin aisles. To examine the effect of contaminate transport down aircraft aisles by a moving body, a motorized beverage cart is past by a contamination source as it traverses the length of the cabin aisle. An experimental study is performed in a mockup Boeing 767 cabin section consisting of eleven rows with seven seats per row. Carbon Dioxide (CO2) tracer gas is injected at a constant flow rate at a location of interest until concentrations in the cabin reach steady state. Ventilation equipment and flow rates representative of an actual aircraft are used for all experiments. Seats in the mockup are occupied by thermal manikins to simulate passenger heat load. A motorized beverage cart traverses the length of the cabin aisle passing by the injection location. The concentrations of tracer gas displaced by the cart are measured at locations throughout the cabin. Comparing these measurements to baseline readings taken with no cart movement, a map of the degree to which contaminant transport is affected by the beverage cart is calculated. The cabin mockup is supplied by 100% outdoor air through actual Boeing supply ductwork and linear diffusers along the cabin length above the aisles. The CO2 level is measured in the inlet air, measurement locations in the cabin, and exhaust air using nondispersive infrared (NDIR) sensors. Measured results are reported for all (54) seat locations downstream of the cart traverse/injection location for an injection location near the rear of the cabin. Analogous measurements are also conducted examining the effect of variations in cart speed and modified injection location. It was found the beverage cart movement had an effect of up to a 35% increase in tracer gas concentration relative to the local steady state concentration for several seat locations adjacent to the aisle. This increased concentration continued for only a few minutes in all cases, but was generally less than the steady state exposure one row closer to the injection location. Moving in the lateral direction away from the aisle, the variance in tracer gas concentration due to the cart movement diminished quickly. The significance of increased concentration for such short periods of time in comparison to the length of actual commercial flights may require further biological analysis. The data showed general tracer gas concentration increases due to cart movement in a small section of the cabin mockup which could warrant further analysis, but increases were generally insignificant when considering entire flight contamination exposure levels.
166

DOPPLER BANDWIDTH CHARACTERIZATION OF ARTM CHANNEL SOUNDING DATA

Landon, David 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Data from ARTM channel sounding test flights is examined to characterize the dynamic channel behavior of aeronautical telemetry channels. The dynamic behavior is characterized using the Doppler power spectrum. The width of the Doppler power spectrum is the Doppler bandwidth of the channel which indicates the required bandwidth of adaptive detection techniques such as adaptive equalization, adaptive modulation, adaptive channel selection and adaptive error control coding. Data collected from ARTM Flight 11 suggest a Doppler bandwidth exceeding 6.7 Hz for the channel, but greater accuracy and resolution will only be possible with more data.
167

SPREAD SPECTRUM COMMUNICATION SCHEME USING PHASESHIFTING SEQUENCE AND ITS PROPERTIES

Zhao, Xianming, Yang, Mingji, Zhou, Tingxian, Meng, Liqun 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / This paper analyzes the pseudo-random characteristic of m-sequence and proposes a spread spectrum communication scheme in which the phase-shifting sequences of msequence can be used as the spread spectrum code under given condition. Therefore, the available spread spectrum code set is expanded. It is theoretically proved that there are some advantages in using phase-shifting sequences instead of the conventional msequences or GOLD-sequences in spread spectrum communication system.
168

DESIGN OF A PARALLEL MULTI-CHANNEL BPSK DIRECT-SEQUENCE SPREAD-SPECTRUM RECEIVER

Sanzhong, Li, Qishan, Zhang, Cheng, L L 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A parallel multi-channel receiver for binary phase shift keyed (BPSK) direct-sequence (DS) spread-spectrum (SS) is introduced in this paper. It adopts a Costas carrier frequency-tracking loop which maintains frequency lock rather than phase lock, and the delay-lock error can be noncoherently obtained to track the PN code. For airborne applications, this method will extend effectively the receiver’s tracking dynamics range for the carrier Doppler shift. A erasable programmable logic device (EPLD) is applied to get the advantage of smaller size and higher flexibility. A high speed microprocessor (TMS320C30) which acts as the processing unit of the receiver is used for acquiring and tracking of the carrier and PN code by digital signal processing algorithms. This receiver is more flexible and is easily improved by reconfiguring the EPLD and modifying the software algorithms. Its fundamental principle is described in the paper.
169

M-ary SPREAD SPECTRUM COMMUNICATION IN TELEMETRY SYSTEMS

Honglin, Zhao, Shijie, Bi, Tingxian, Zhou 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper analyzes the performance of an M-ary spread spectrum system with orthogonal codes. A new scheme of M-ary spread spectrum communication with phase shifted msequence is proposed, and the method to implement code synchronization in the scheme is given. The performance of the new scheme is analyzed, and compared to conventional spread spectrum systems and orthogonal code M-ary systems. The results show that stronger anti-interference ability, and better data transmission efficiency, and lower complexity is achieved in the system employing phase shifted m-sequence.
170

INTRODUCTORY SYSTEM DESIGN OF THE ADVANCED SUBMINIATURE TELEMETRY SYSTEM

Dacus, Farron L., Hendrix, Steven P., Bouchez, Joseph J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Advanced SubMiniature Telemetry System (ASMT) with Wireless Sensor extension is an ambitious program aimed at incorporating modern wireless system and electronic design methods into a two way, miniature, low cost, modular, and completely software controlled wireless data acquisition system. The program was conceived and is sponsored by the U.S. Air Force SEEK EAGLE Office as a means of both lowering test cost and increasing test effectiveness. This article shall present the fundamental system design challenges of the program and how modern design methods can provide a new standard of cost effectiveness, mission capability, and high spectral efficiency.

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