The purpose of this thesis aims that common investors are expected to apply three kinds of active portfolio management without complex mathematical numeration to reduce investment risk or loss to get profits on Taiwan stock exchange capitalization weighted stock index options market. They are Constant Portion Portfolio Insurance Strategy (named CPPI), Time-Invariant Portfolio Protection (named TIPP) and Constant Mix Strategy (named CMS). The active managements adopt bull and bear spread as an adjustment of risk positions on the option market. Five research results are as followings: 1. The performance of the portfolio managements as Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection is better than that of the management as Constant Mix Strategy. And Floor value of the portfolio management as Time - Invariant Portfolio Protection exceeds that of the portfolio management as Constant Portion Portfolio Insurance Strategy. 2. Due to the regulation of margin system by Taiwan Future Exchange, the positions of Bull Call Spread and Bear Put Spread can be greater than ones of Bull Put Spread and Bear Call Spread. 3. The more differences between two strike prices on the spread option means to be able to get more profit opportunities. 4. Greater multiplier number and profit have inverse relationship. That only occurs on portfolio managements in Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection. 5. Setting upper and low limitation of single return rate for offsetting will have better performance than no limitations for the managements in Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection.

A full-scale ASTM E 1321 Lateral ignition and Flame Transport (LIFT) apparatus was constructed and compared with a Reduced scale Ignition and Flame spread Test apparatus (RIFT) adaptation of the cone calorimeter in the vertical position. The objective was to find a low cost and simple alternative to the LIFT apparatus for measuring opposed flow flame spread. Ignition tests were conducted using the LIFT, RIFT and ISO 5657 ignitability apparatus and flame spread experiments were conducted in the LIFT and RIFT. Nine different types of timber based products were tested for ignition and flame spread, and Quintiere's flame spread model was applied to the results to obtain material properties, such as thermal inertia, flame spread parameter and the minimum heat flux required for flame spread. These materials included plywood, medium density fibreboard (MDF), hardboard, particle board flooring, Melamine (Melteca) covered MDF, New Zealand Rimu, and Beech and New Zealand grown Macrocarpa and Radiata (Monterey) Pine. Further limited tests were conducted on Melteca covered particle board, and a second brand of particle board. The materials in the RIFT were tried with and without preheating to equilibrium. In addition, a view factor for the RIFT was developed, based on earlier work for the cone calorimeter element. The view factor equation was experimentally tested against measured values, and the calculated value was consistently lower than the experimental values, with similar flux profile. The standard procedure is for the material to be preheated before ignition, so that the surface is at equilibrium. The spread of the flame front past points on the sample surface after ignition is recorded, and from the flame front velocity and the model by Quintiere, material specific properties can be derived. The lack of preheating was found to affect the final results, by reducing the flame spread velocity and increasing the scatter in the experimental results. The RIFT gives comparable results to the same materials tested in the LIFT and to the published literature. The results the flame spread parameter and the minimum flux for flame spread are usually higher for the RIFT against the same material in the LIFT. There proved to be an effective limit on suitable materials able to be successfully tested in the RIFT to those that have a minimum flux for flame spread of less than 7kW/m2, with this limitation is dictated by the flux profile along the sample, and the lower resolution dictated by the smaller size. It is approximately equivalent to a minimum ignition flux of 18kW/m2.

Orientador: Lireny Aparecida Guaraldo Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-22T11:28:01Z (GMT). No. of bitstreams: 1 Ambiel_HiriaCristinaIfanger_M.pdf: 1422027 bytes, checksum: 9c0f8cb70e90f3805ce08294a44ca9c2 (MD5) Previous issue date: 2013 / Resumo: O spread é um creme de chocolate espalhável, composto basicamente de óleo, gordura vegetal, açúcar, cacau em pó e lecitina de soja. Atualmente o uso de spread de chocolate não se restringe apenas ao varejo, mas também têm sido largamente aplicado no mercado de panificação, que o utiliza para decoração de produtos de confeitaria, recheios, coberturas etc. Pelo alto teor de óleo, um dos problemas enfrentados pela indústria é a exsudação, que é agravada em temperaturas elevadas de armazenamento e transporte. Uma das formas de se evitar a exsudação de óleo é a utilização de hardfats, que são gorduras de alto ponto de fusão e que aceleram a velocidade de cristalização da gordura, ocluindo o óleo da formulação. No entanto, para uso específico em spreads, esta matéria-prima é importada, o que dificulta o seu fornecimento e o seu custo torna-se elevado. Assim, o desenvolvimento de uma opção de hardfat nacional para uso específico em spreads de chocolate, visando à redução da exsudação de óleo durante o armazenamento, é interessante sob o ponto de vista da indústria de alimentos. A partir da análise da composição de ácidos graxos da amostra de hardfat importada, optou-se pela utilização de óleo de algodão (OA) e óleo de crambe (Crambe abyssinica) totalmente hidrogenado (OCTH) para a composição da hardfat nacional. A produção da hardfat foi realizada através da interesterificação química, em escala laboratorial, de misturas destes óleos, nas proporções de 90:10, 80:20, 70:30, 60:40 e 50:50 OA:OCTH. O estudo dos perfis destas misturas foi feito pela comparação das amostras antes e após a reação de interesterificação com a hardfat importada. Análises de perfil de ácidos graxos, conteúdo de gordura sólida, isoterma de cristalização das gorduras puras e das misturas das gorduras presentes na formulação do spread foram realizadas para definição da fração de OA:OCTH que apresentasse o resultado próximo ao da hardfat importada. As frações 60:40 e 50:50 OA:OCTH apresentaram os melhores resultados, sendo então analisadas termicamente através da Calorimetria de Varredura Diferencial, Difração de Raio-X e Microscopia Sob Luz Polarizada, juntamente com a hardfat importada. Estas gorduras foram escolhidas e aplicadas na formulação de spread de chocolate com o objetivo de avaliar a exsudação de óleo durante o armazenamento em temperaturas altas. Verificouse que a fração 50:50 OA:OCTH apresentou resultados semelhantes ao da hardfat importada, indicado que esta hardfat poderá ser uma opção à indústria brasileira para minimizar a exsudação de óleo em spread de chocolate / Abstract: The spread is a spreadable chocolate cream, consisting essentially of oil, vegetable shortening, sugar, cocoa powder and soya lecithin. Currently the use of chocolate spread is not restricted to retail, but it has also been widely applied by the bakery market that uses this product in confectionery product as fillings, covertures etc. Because of the high amount of oil, one of the problems that the industry faces is the exudation, which is exacerbated at elevated temperatures during transport or storage. One way to avoid oil exudation is using hardfats which occludes the oil and accelerates the crystallization rate of the fat because of their high melting point. However, since this raw material is imported it makes supply more difficult and increases its price, thus developing a national hardfat for specific use in chocolate spreads aimed at reducing oil exudation during Storage is interesting from the point of view of food industry. After analyzing the fatty acid composition of imported hardfat (HF) we chose to use cottonseed oil (OA) and fully hydrogenated crambe oil (OCTH) (Crambe abyssinica) for the composition of the national hardfat. At laboratory scale, the production of hardfat was performed by chemical interesterification of mixtures of these oils in proportions of 90:10, 80:20, 70:30, 60:40 and 50:50 OA: OCTH. The study on the profiles of such mixtures was made by comparing the samples before and after interesterification reaction with the HF. In order to define the fraction of OA: OCTH which has similar results as the HF, some analysis were performed on fatty acid profiles, solid fat content, crystallization isotherm of pure fats and mixtures of fats presented in the formulation of the spread. The fractions 60:40 and 50:50 OA: OCTH showed the best results, being afterwards thermally analyzed by Differential Scanning Calorimetry, X-ray Diffraction and Polarized Light Microscopy. These fats have been selected and applied in the formulation of chocolate spread in order to evaluate the oil exudation during storage at high temperatures. It was found that the fraction 50:50 OA: OCTH showed similar results to the HF indicating that this may be an option for the Brazilian industry to minimize exudation of oil in chocolate spread during storage and transportation / Mestrado / Tecnologia de Alimentos / Mestra em Tecnologia de Alimentos

Economists often use complex mathematical models to forecast the future path of the economy and the likelihood of recession. But more simple indicators such as interest rates, stock price indices, and monetary aggregates also contain some relevant information about future economic activity. In this thesis we revisit the usefulness of one such indicator, the yield curve or, more specifically, the spread between the interest rates on the ten-year Treasury note and the three-month Treasury bill. By using four different models we examine whether the yield spread has still some predicitve power for future real GDP growth in selected european countries. What is more, we are comparing the predictive power of the yield spread with different variables, both in- sample and out-of-sample. We decompose the yield spread into expectations effect and term premium effect in order to investigate which factor contributes more to predicting real GDP growth. Using modified definition of recession we conclude that that yield spread still contains some useful information for predicting future economic activity, although its predictive power deteriorates.

Acoustic models are useful tools to increase understanding of cochlear implant perception. Two particular issues in modelling cochlear implant perception were considered in the present study, which aimed at improving acoustic models. The first included an electricallayer in the model, while the second manipulated synthesis signal parameters. Two parts of the study explored the effects of current decay, compression function and simultaneous stimulation, by including the electrical layer. The SPREAD model, which incorporated this layer, yielded the asymptote in speech intelligibility at seven channels observed in CI listeners. It was shown that the intensity of border channels was deemphasized in relation to more central channels. This was caused by the one-sided effects of current spread from neighbouring channels for the border channels, as opposed to the two-sided effects for the more central channels. It was theorised that more compressive mapping functions would affect spectral cues and consequently speech intelligibility, but speech intelligibility experiments did not confirm this theory. A simultaneous analogue stimulation (SAS) model, which modelled simultaneous stimulation, yielded intelligibility results that were lower than those of the SPREAD model at 16 channels. The SAS model also appeared to introduce more temporal distortion than the SPREAD model. A third part of the study endeavoured to improve correspondence of acoustic model results with cochlear implant listener results by using nine different synthesis signals. The best synthesis signal was noise-band based. The widths of these increased linearly from 0.4 mm at the apical to 8 mm at the basal end. Good correspondence between speech recognition outcomes using this synthesis signal with those of CI listeners was found. AFRIKAANS : Akoesties modelle word algemeen gebruik om die persepsie van inplantingsgebruikers beter te verstaan. Twee benaderings tot die modellering van kogleêre inplantingsgebruikerpersepsies is voorgestel om akoestiese modelle te verbeter. In die eerste benadering is die generiese model verbeter deur die byvoeging van 'n elektriese laag en in die tweede benadering is sinteseseinparameters gemanipuleer om die ooreenkoms met inplantingsgebruikersuitkomste te verbeter. Twee dele van die studie het die effek van stroomverspreiding, samedrukkings-funksie en gelyktydige stimulasie ondersoek deur die insluiting van die elektriese laag. Die SPREAD-model het die asimptoot in spraakherkenning by sewe kanale getoon. Die intensiteit van grenskanale is onderbeklemtoon in verhouding met meer sentrale kanale. Dit is veroorsaak deur die eensydige effekte van stroomverspreiding vir die grenskanale, teenoor die tweesydige effekte wat meer sentrale kanale tipies beïnvloed. Die model het gesuggereer dat meer samedrukkende funksies spektrale inligting sou affekteer, maar spraakherkenningsdata het nie hierdie teorie bevestig nie. Die gelyktydige- analoogstimulasiemodel, wat gelyktydige stimulasie gemodelleer het, het soortgelyke tendense getoon, maar met meer temporale effekte as die SPREAD-model. Die gelyktydige- analoogstimulasiemodel-model se resultate was ook swakker by 16 kanale as die SPREAD-modelresultate. Die derde deel van die studie het gepoog om beter ooreenkoms tussen modeluitkomste en inplantingsgebruikeruitkomste te verkry deur nege verskillende sinteseseine te gebruik. Die beste sintesesein was die ruisband met veranderende wydte; hierdie wydte het verbreed vanaf 0.4 mm by die apeks tot by 8 mm by die basis. 'n Goeie ooreenkoms is verkry tussen modeluitkomste en inplantingsgebruikeruitkomste deur hierdie sintesesein te gebruik. / Thesis (PhD)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / Unrestricted

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / According to the advantages of chaotic analog sequences and chaotic binary sequences, this paper proposes a method generating chaotic binary spread-spectrum sequence by multilevel quantifying. This paper proved that even correlation and odd correlation between such sequences of length N are all Gaussian distributed with mean 0 and variance N, the even of mean-square cross-correlation is N, and the variance of mean-square cross-correlation is 2N. The method can increase the number of chaotic sequences, made the spread-spectrum system more secure. The theoretical analyses and the results of simulation show that the performance of such sequence general is as same as traditional spread-spectrum sequence, its number is very large, and can be used in CDMA in future.

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The focus of this dissertation is the performance analyses of two classes of frequency-hopped spread-spectrum multiple access (FH-SSMA) systems in various fading environments. The capacity of Viterbi’s FH-SSMA system is evaluated under three types of fading, namely Rician, shadowed Rician, and Nakagami fading. The results of recent experiments have indicated that these fading phenomena occur in various environments where the FH-SSMA system may be implemented. In this dissertation, the deletion probability for each fading scenario is derived. Subsequently, the system capacity is analyzed in terms of maximum number of users versus average bit error rate. The effect of a change in the signal-to-noise ratio level on the system capacity is also demonstrated. For Rician fading, it is found that the capacity of the system with a Rician factor of 2 dB is reduced by 13 percent as compared to the capacity of the non-fading case. For shadowed Rician fading, three shadowing scenarios are considered: light, average, and heavy. It is shown that the light and the average shadowing scenarios provide only a slight decrease in the capacity, while the heavy shadowing scenario renders a capacity identical to that for the Rayleigh fading case. Finally, for Nakagami fading the capacity is found to decrease by 50 percent as the fading parameter is reduced to 0.5. The performance of a cellular frequency-hopped spread-spectrum multiple access system is studied under an indoor environment. It is demonstrated how the system capacity, given in terms of the number of users per cell, is affected by the number of cells in the system. Also, the influence of the delay spread, which is the result of multipath propagation, is investigated. The analysis focuses on a worst-case scenario where a user receives both the desired and interfering signals with equal power levels. This scenario applies to both the downlink and the uplink. It is shown that the system capacity is reduced drastically as the number of adjacent interfering cells increases from one to three. Previous work concerning the indoor multipath propagation assumed that the number of paths is fixed, the path delays are uniformly distributed, and the path gains are equal. In this dissertation, a more realistic channel model derived from actual impulse response measurements by Saleh and Valenzuela is employed. The model consists of clusters of rays with constant cluster and ray arrival rates and power-delay time constants. The system performance is shown to be affected strongly by the change in the power-delay time constants, yet only slightly influenced by the variation in the arrival rates of the rays and clusters. In addition, the degradation in the system performance due to the delay spread becomes more severe as the transmission rate increases. / Graduate