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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.
91

ATOMS (Adjustable Transobturator Male System) Is an Effective and Safe Second-Line Treatment Option for Recurrent Urinary Incontinence after Implantation of an AdVance/AdVance XP Fixed Male Sling? A Multicenter Cohort Analysis

Queissert, Fabian, Rourke, Keith, Schönburg, Sandra, Giammò, Alessandro, Gonsior, Andreas, González-Enguita, Carmen, Romero, Antonio, Schrader, Andres J., Cruz, Francisco, Martins, Francisco E., Dorado, Juan F., Angulo, Javier C. 04 May 2023 (has links)
(1) Background: This study examined outcomes of second-line ATOMS implantation after failure of the fixed male sling (FMS) AdVance/AdVance XP. (2) Methods: A retrospective multicenter cohort analysis was carried out in men implanted with an ATOMS between 2011 and 2020 after failure of an AdVance/AdVance XP. Success was assessed on the basis of objective (dryness, 0–1 pad/24 h or >20 g/24 h pad test) and subjective results (PGI-I). We performed the Wilcoxon rank sum test, Fisher’s exact test, logistic regression, and multivariate analysis. (3) Results: The study included 88 patients from 9 centers with a mean age of 71.3 years. No Clavien–Dindo > II complications occurred within the first 3 months after ATOMS implantation. A total of 10 cases (9%) required revision in the ensuing clinical course. After a mean follow-up of 42.5 months, 76.1% achieved social continence, and 56.8% used no pads at all. Mean urine leakage/24 h dropped from 422 g (3.9 pads) to 38 g (0.69 pads) and the mean ICIQ-SF decreased from 16.25 to 5.3 (p < 0.0001). PROMs (patient-reported outcome measures) showed improvement in 98.9% of cases, and 63.6% gave a “very much better” PGI-I rating. Multivariate analysis identified a lower probability of achieving maximum satisfaction for the following factors: the AdVance XP as first-line therapy (OR 0.35), a lower ICIQ-SF question 1 (OR 0.26), status post-irradiation (OR 0.14), and more severe pain prior to ATOMS implantation (OR 0.51). (4) Conclusions: Implantation of an ATOMS is an effective and safe second-line treatment option for recurrent urinary incontinence after implantation of an AdVance/AdVance XP sling. High patient satisfaction was demonstrated in a long-term follow-up.
92

Design, Preparation and Characterization of Novel Pseudorotaxanes, Semirotaxanes, Rotaxanes, Non-Covalent Supramolecular Polymers and Polycatenanes

Niu, Zhenbin 17 October 2011 (has links)
Design and preparation of novel host/guest systems, such as pseudorotaxanes, semirotaxanes, rotaxanes and catenanes, with high association constants, enhanced yields and the abilities to respond to external stimuli are of great importance and significance due to their topological novelty and potential application. The convergence of supramolecular chemistry with polymer science provides an important way to extend the scope of polymer and material sciences by incorporating designed host/guest systems into polymers, and the resulting non-covalently linked supramolecular polymers are expected to have unusual properties due to their unique architectures compared with traditional polymers. After discovery of bis(meta-phenylene)-32-crown-10 (BMP32C10) derivative/paraquat complexes, for about a quarter century only “taco”-shaped complexes were observed by X-ray crystallography. Here, by the self-assembly of a BMP32C10 bearing two electron-donating groups (carbazoles) with electron-accepting paraquat derivatives, the first [2]pseudorotaxane and the first pseudocryptand-type poly[2]pseudorotaxane based on BMP32C10 were isolated as crystalline solids as shown by X-ray analyses. The first dual component pseudocryptand-type [2]pseudorotaxanes were designed and prepared via the self-assembly of synthetically easily accessible BMP32C10 pyridyl, quinolyl and naphthyridyl derivatives with paraquat. The formation of the pseudocryptand structures in the complexes remarkably improved the association constants by forming the third pseudo-bridge via H-bonding with the guest and π-stacking of the heterocyclic units. A pseudocryptand-type [2]pseudorotaxane was formed via the self-assembly of a dipyridyl BMP32C10 derivative and a paraquat derivative. Due to the basicity of the pyridyl group, which forms the third pseudo-bridge of the pseudocryptand, this pseudorotaxane represents the first system with acid-base adjustable association constants, i. e., finite both under acidic and neutral conditions. The first pseudocryptand-type supramolecular [3]pseudorotaxane was designed and prepared via the self-assembly of a bispicolinate BMP32C10 derivative and a bisparaquat. The complexation behavior was cooperative. In addition, the complex comprised of the BMP32C10 derivative and a cyclic bisparaquat demonstrated strong binding; interestingly, a poly[2]pseudocatenane structure was formed in the solid state for the first time. Two novel BMP32C10 cryptands, bearing covalent and metal complex linkages, were designed and prepared. By employing the self-assembly of these biscryptands, which can be viewed as AA monomers, and a bisparaquat, which can be viewed as a BB monomer, the first AA/BB-type linear supramolecular polymers with relatively high molecular weights were successfully prepared. Via the self-assembly of two BMP32C10-based cryptands, bearing covalent and metal complex (ferrocene) linkages, with dimethyl paraquat, novel [3]pseudorotaxanes were formed statistically and anticooperatively, respectively. From a hydroxyl-functionalized secondary ammonium salt a [2]semirotaxane and a [2]rotaxane were prepared successfully with dibenzo-24-crown-8 (DB24C8). X-ray analysis of a single crystal of the [2]semirotaxane confirmed its semirotaxane nature. In addition, the formation of the [2]semirotaxane can be reversibly controlled by adding KPF6 and 18C6 sequentially. This system affords a way to prepare novel supramolecular polymers. Dibenzo-30-crown-10 (DB30C10) derivatives and pyridine-based DB30C10 cryptands were prepared by employing the templating method established by our group. A [2]pseudorotaxane was prepared based on DB30C10 diol and paraquat diol. The [3]pseudorotaxane formed via the self-assembly between DB30C10 cryptand and bisparaquat diol occurred in a cooperative manner. In addition, a bromo-functionalized DB30C10 cryptand was successfully designed and prepared. An alkyne-functionalized DB30C10 cryptand was designed and is under preparation; its precursors have been prepared successfully. In the future, based on these functionalized cryptands and paraquat salts, AA and AB type monomers will be prepared. Via the self-assembly between these monomers, non-covalent supramolecular polymers with high molecular weight will be afforded. A novel DB30C10 cryptand bearing an organometallic bridge, ferrocene, was prepared via 1-(3'-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) coupling of the crown ether diol with ferrocene dicarboxylic acid. The cryptand is dimerized in the solid state via π, π-stacking and hydrogen bonds. The ferrocene-based cryptand formed novel [2]pseudorotaxanes with paraquat and diquat PF₆ salts with association constants (Kₐ) of 1.7 ± 0.1 x 10³ and 4.2 ± 0.3 x 10⁴ M⁻¹ in acetone-d₆, respectively. In order to prepare linear polycatenanes, the preparation of which represent a real synthetic challenge, a series phenanthroline derivatives were designed and prepared. A “U” shaped monomer was successfully prepared in relative high yield with good solubility. In the future, real linear polycatenanes will be prepared. In addition, a novel diphenanthroline-based BMP32C10 derivative was prepared in high yield and the complexation behavior between it and dimethyl paraquat was studied. / Ph. D.
93

Jacking and Equalizing Cylinders for NASA- Crawler Transporter

Rühlicke, Ingo 03 May 2016 (has links) (PDF)
For the transport of their spacecraft from the vehicle assembly building to the launch pads at Kennedy Space Centre, Florida, the National Aeronautics and Space Administration (NASA) is using two special crawler transporters since 1965. First developed for the Saturn V rocket the crawler transporters have been sufficient for all following generations of space ships so far. But for the new generation of Orionspacecraft which is under development now, a load capacity increase for the crawler transporter of plus 50% was necessary. For this task Hunger Hydraulik did develop new jacking, equalizing and levelling (JEL) cylinders with sufficient load capacity but also with some new features to improve the availability, reliability and safety of this system. After design approval and manufacture of the cylinders they have been tested in a special developed one-to-one scale dynamic test rig and after passing this the cylinders had to prove their performance in the crawler transporter itself. This article describes the general application and introduces the technical requirements of this project as well as the realized solution.
94

Choice of contract maturity with applications to international and mortgage lending

Touna Mama, Albert Le Grand January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.
95

Self-tuning PID and Fuzzy controllers in industrial plants / Controladores PID auto-ajustÃvel e nebuloso aplicados em plantas industriais

Felipe de Azevedo GuimarÃes 01 October 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / With the globalization and the competitiveness in all the levels of the industrial sector, the final product quality search became higher. On the other hand, energy saving became another important factor in modern industry. The consumption of electric energy in the industrial sector represents 45.5% of the total consumption of the country. The motor force represents most of this consumption, arriving to be superior of 80% in the textile, paper and cellulose sectors. This work presents two strategies of control, auto-adjustable PID and fuzzy controller, the objectives are a better final product quality and the energy saving. Ventilation and compression industrials process are used in this work. An analysis of limit cyclesâ presence through the descriptive function of the fuzzy controller is carried through, providing a previously validation of fuzzy controllerâs parameters by simulations, saving time in the adjust phase. Set-point changes are easily made and on-line, still the process is running, in the two considered controllers. Comparisons of energy consumption are made between the conventional strategies and the two strategies considered in this work. / Com a globalizaÃÃo e a competitividade em todos os nÃveis do setor industrial, a qualidade do produto final se tornou de importÃncia crescente. Por outro lado, a conservaÃÃo de energia no setor industrial se tornou outro fator importante na indÃstria moderna. O consumo de energia elÃtrica do setor industrial representa 45,5% do consumo total do paÃs. A forÃa motriz representa a maior parte deste consumo, chegando a ser superior a 80% nos setores tÃxtil, de papel e celulose. Este trabalho apresenta duas estratÃgias de controle, PID auto-ajustÃvel e controlador nebuloso, e tÃm como objetivos tanto a qualidade do produto final quanto a eficiÃncia energÃtica. SÃo utilizados processos de ventilaÃÃo e de compressÃo em escala industriais. Uma anÃlise da presenÃa dos ciclos limites atravÃs da funÃÃo descritiva do controlador nebuloso à realizada, de forma que os parÃmetros do controlador nebuloso podem ser previamente validados atravÃs de simulaÃÃes, poupando tempo na fase de ajuste dos parÃmentros do controlador. MudanÃas de set-point sÃo facilmente realizadas de forma online e sem que o funcionamento do processo seja descontinuado, nos dois controladores propostos. ComparaÃÃes quanto ao consumo de energia sÃo realizadas usando as estratÃgias de controle convencionais e as proposta neste trabalho.
96

履約價格可調整之認購權證研究--財務工程之應用 / The research of strike price adjustable warrants - the application of financial engineering

謝文雄, Hsieh, Wen-Hsiung Unknown Date (has links)
自 1997 年 9 月起,證券商開始獲准發行認購權證,由於證券商發行認購權證的時機與選擇標的物之不當,造成許多投資人之虧損,而機構投資人也多採取觀望態度,加上主管機關對於發行者在法令及課稅上的限制,導致整個認購權證市場交易冷清,未能發揮認購權證應有的避險功能。而本文所研究之可調整型(Adjustable)認購權證,是屬於新型的認購權證,此產品可以在契約內容中規定,在認購權證發行之後,若標的物證券之價格在一定期限之內,標的股價跌破原股價的某一比例(h),可以將履約價格(Strike Price)向下調整某一比例(l),以避免造成認購權證在剛推出不久,就因為標的物價格大跌,而使得投資人蒙受損失。相較於一般的認購權證,「可調整型」認購權證可以造成投資人獲利機會的保障增加、發行者權利金收益增加,並且因此使得衍生性金融市場更加活絡,造成三贏的局面。 Cox, Ross and Rubinstein(1979)提出二項評價模式,其利用風險中立 ( Risk Neutral ) 的論點,以間斷的股價過程代替 Black-Scholes(1973) 模式所假設的連續股價隨機過程,本文研究之「可調整型」認購權證之評價模式,以二項評價模式為出發點,利用此模式在一些特定的限制條件之下,配合路徑決定型選擇權、界線選擇權之概念,對「可調整型」認購權證做出合理的評價,另外,本研究以 Matlab 程式語言,撰寫出「可調整型」認購權證的價格,並使用模擬(Simulation) 的方式,探討「可調整型」認購權證的特性及避險方式與效果,以期提供券商、一般企業及投資者最佳的避險及獲利管道,其主要結果如下: 1.在評價「可調整型」認購權證時,時間間隔(Time Step)愈大時,電腦計算的時間效率愈差,若 Time Step 大於 80 時,其價格差異性會低於百分之二。 2.h 與「可調整型」認購權證價格呈正向變動關係,l 與「可調整型」認購權證價格呈反向變動關係。本文條件之下,h 落於 0.6-0.8 之間、l 落於 0.4-0.6 之間,對於「可調整型」認購權證價格之影響最大。 3.「可調整型」認購權證與一般型認購權證的差價比例,隨波動率增加而增加。 4.隨波動率之增加,一般型認購權證之 vega 值有大於「可調整型」認購權證 vega 值的趨勢。 5.在利用 delta 避險策略之下,以獲利金額來看,波動率大之股票較適合發行「可調整型」認購權證,波動率小之股票較適合發行一般型認購權證。 因為「可調整型」認購權證目前在台灣並沒有實證資料,因此無法評估本文模型之價格與實際價格之誤差,未來若出現此新金融商品時,可以評估理論與實際之差異。本文中並未探討利率對於「可調整型」認購權證之影響,後續研究可以討論利率之變動對於此新型認購權證之影響。 / From September 1997,the SEC permits warrants listing in Taiwan's security market. Because of the improper issuing timing and inappropriate underlying assets, many investors get great loss in warrant investment. Besides, many other restrictions from the government make the warrants market more inactive, and then the warrants cannot proper the hedging market. Researching the strike price adjustable warrants is this thesis subject. This innovative warrant allows the strike price(K) adjusting to lK(0<l<1), when the price of underlying asset is lower than the barrier(hS). This article studies the pricing model and hedging strategies of adjustable warrants. The pricing of the adjustable warrants uses some option pricing formulae, like the binomial option pricing model、path-dependent options、barrier options. This article uses Matlab language to price the adjustable warrants, and then uses simulation method to discuss the characteristics and the hedging strategies of the adjustable warrants. Following are the results: 1.When pricing the adjustable warrants, the more time step we choice, the more computer pricing time we get. If the time step is more than 80, the price difference is less than 2%. 2.Toward adjustable warrants(AW) price, h has the positive effect and l has the negative effect. When 0.6<h<0.8 and 0.4<l<0.6 , the AW price has the most sensitivity. 3.As the volatility raising, the difference from AW price and plain vanilla warrant price will become greater. 4.As the volatility raising, the vega of plain vanilla warrant will become greater than the vega of AW. 5.Using the delta hedge, from the profit aspect, high volatility stock is suitable for AW and low volatility stock is suitable for plain vanilla warrant. Because there are no practical information of AW in Taiwan's warrant market, so we cannot evaluate the pricing error form our model. If this kind of product enters the market in the future, we can compare difference of AW between theoretical and empirical price.
97

Roller skis' rolling resistance and grip characteristics : influences on physiological and performance measures in cross-country skiers

Ainegren, Mats January 2012 (has links)
The aim of this thesis was to investigate roller ski characteristics; classical and freestyle roller skis’ rolling resistance coefficients (μR) and classical style roller skis’ static friction coefficients (μS), and to study the influence of different μR and μS on cross-country skiers’ performance and both physiological and biomechanical indices. The aim was also to study differences in skiing economy and efficiency between recreational skiers, female and male junior and senior elite cross-country skiers.The experiments showed that during a time period of 30 minutes of rolling on a treadmill (warm-up), μR decreased significantly (p&lt;0.05) to about 60-65 % and 70-75 % of its initial value for freestyle and classical roller skis respectively. Also, there was a significant influence of normal force on μR, while different velocities and inclinations of the treadmill only resulted in small changes in μR.The study of the influence on physiological variables of a ~50 % change in μR showed that during submaximal steady rate exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non-significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a change in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non-significant or small.The study of classical style roller skis μS showed values that were five to eight times more than the values of μS reported from on-snow skiing with grip-waxed cross-country skis.The subsequent physiological and biomechanical experiments with different μS showed a significantly lower skiing economy (~14 % higher v̇O2), higher heart rate, lower propulsive forces coming from the legs and shorter time to exhaustion (~30 %) when using a different type of roller ski with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a (similar) higher μS.The part of the thesis which focused on skiing economy and efficiency as a function of skill, age and gender, showed that the elite cross-country skiers had better skiing economy and higher gross efficiency (5-18 %) compared with the recreational skiers, and the senior elite had better economy and higher efficiency (4-5 %) than their junior counterparts, while no differences could be found between the genders. / Syftet med denna avhandling var att undersöka fristils- och klassiska rullskidors rullmotståndskoefficienter (μR) och klassiska rullskidors statiska friktionskoefficienter (μS) samt effekter av olika μR och μS på längdskidåkares prestation vid rullskidåkning på rullande band. Syftet var även att undersöka s.k. åkekonomi och mekanisk verkningsgrad mellan motionärer och kvinnliga och manliga junior- och seniorlängdskidåkare på elitnivå.Experimenten visade att under en period av 30 minuters kontinuerligt rullande, på rullande band, så sjönk μR signifikant (p&lt;0.05) till 60-65 % och 70-75 % av initiala värden, för fristils- respektive klassiska rullskidor. Undersökandet av olika normalkrafter, hastigheter och lutningars påverkan på μR resulterade i en signifikant, negativ korrelation för μR som funktion av normalkraft, medan olika hastigheter och lutningar endast medförde små förändringar av μR.Studien som undersökte fysiologiska effekter av olika μR visade, vid submaximala konstanta arbetsbelastningar, att yttre effekt, syreupptagning, hjärtfrekvens och blodlaktat förändrades signifikant vid ~50 % förändring av μR. Försökspersonernas frekvens och sträcka per frekvens samt skattning av upplevd ansträngning resulterade dock i mestadels icke signifikanta eller små förändringar. Protokollen med successivt ökande arbetsbelastning (maxtest) resulterade i signifikant förändrad tid till utmattning, vid ~50 % förändring av μR. Detta inträffade utan signifikant skillnad i maximal syreupptagning, hjärtfrekvens och blodlaktat, vilket även mestadels gällde för skattning av upplevd ansträngning.Experimenten som undersökte klassiska rullskidors μS visade att dessa erhöll värden som är fem till åtta gånger högre än vad som rapporterats från studier av μS på snö med fästvallade skidor.Den efterföljande studien som undersökte fysiologiska och biomekaniska influenser av olika μS visade, vid submaximala konstanta arbetsbelastningar, att åkekonomin försämrades (~14 % högre syreförbrukning), hjärtfrekvensen ökade, den framåtdrivande kraften från benen på rullskidorna minskade samt att det blev kortare tid till utmattning (~30 %), vid maxtest, när skidåkarna använde rullskidor med en μS i likhet med vad som rapporterats för skidåkning på snö. För arbetsförsöken med olika rullskidor av olika fabrikat med en högre, och likartad, μS förelåg ingen skillnad i de undersökta variablerna.Studien som undersökte åkekonomi och mekanisk verkningsgrad som funktion av prestationsnivå, ålder och kön, visade att elitskidåkarna hade bättre åkekonomi och verkningsgrad (5-18 %) i jämförelse med motionärerna, att seniorerna hade bättre åkekonomi och verkningsgrad (4-5 %) än juniorerna och att ingen skillnad kunde konstateras mellan könen.
98

Distributed Energy-Efficient Solutions for Area Coverage Problems in Wireless Sensor Networks

Vu, Chinh Trung 11 June 2009 (has links)
Wireless sensor networks (WSNs) have recently attracted a great deal of attention due to their numerous attractive applications in many different fields. Sensors and WSNs possess a number of special characteristics that make them very promising in a wide range of applications, but they also put on them lots of constraints that make issues in sensor network particularly challenging. These issues may include topology control, routing, coverage, security, data management and many others. Among them, coverage problem is one of the most fundamental ones for which a WSN has to watch over the environment such as a forest (area coverage) or set of subjects such as collection of precious renaissance paintings (target of point coverage) in order for the network to be able to collect environment parameters, and maybe further monitor the environment. In this dissertation, we highly focus on the area coverage problem. With no assumption of sensors’ locations (i.e., the sensor network is randomly deployed), we only consider distributed and parallel scheduling methods with the ultimate objective of maximizing network lifetime. Additionally, the proposed solutions (including algorithms, a scheme, and a framework) have to be energy-efficient. Generally, we investigate numerous generalizations and variants of the basic coverage problem. Those problems of interest include k-coverage, composite event detection, partial coverage, and coverage for adjustable sensing range network. Various proposed algorithms. In addition, a scheme and a framework are also suggested to solve those problems. The scheme, which is designed for emergency alarming applications, specifies the guidelines for data and communication patterns that significantly reduce the energy consumption and guarantee very low notification delay. For partial coverage problem, we propose a universal framework (consisting of four strategies) which can take almost any complete-coverage algorithm as an input to generate an algorithm for partial coverage. Among the four strategies, two pairs of strategies are trade-off in terms of network lifetime and coverage uniformity. Extensive simulations are conducted to validate the efficiency of each of our proposed solutions.
99

Choice of contract maturity with applications to international and mortgage lending

Touna Mama, Albert Le Grand January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal
100

Fluidic microchemomechanical integrated circuits processing chemical information

Greiner, Rinaldo, Allerdissen, Merle, Voigt, Andreas, Richter, Andreas 08 April 2014 (has links) (PDF)
Lab-on-a-chip (LOC) technology has blossomed into a major new technology fundamentally influencing the sciences of life and nature. From a systemic point of view however, microfluidics is still in its infancy. Here, we present the concept of a microfluidic central processing unit (CPU) which shows remarkable similarities to early electronic Von Neumann microprocessors. It combines both control and execution units and, moreover, the complete power supply on a single chip and introduces the decision-making ability regarding chemical information into fluidic integrated circuits (ICs). As a consequence of this system concept, the ICs process chemical information completely in a self-controlled manner and energetically self-sustaining. The ICs are fabricated by layer-by-layer deposition of several overlapping layers based on different intrinsically active polymers. As examples we present two microchips carrying out long-term monitoring of critical parameters by around-the-clock sampling. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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