Au cours de ce projet de recherche, nous nous sommes intéressés à la synthèse de motifs hétérospiraniques énantioenrichis. De ce fait, notre équipe a pu élaborer une nouvelle voie synthétique pouvant conduire à la synthèse de molécules possédant des structures bicycliques spiraniques diverses. Cette voie de synthèse inédite est articulée sur une réaction de nitroso Diels-Alder. Le contrôle de la stéréosélectivité ainsi que le contrôle de la régiosélectivité, peu décrit dans la littérature, ont été spécifiquement étudiés lors de ces travaux. Nos différentes études ont permis de mieux appréhender ces aspects de la réaction de nitroso Diels-Alder. Deux approches différentes ont d’ailleurs été développées au cours de ces travaux. Celles-ci ont toutes deux conduit a un contrôle total de la régiosélectivité de cette cycloaddition. Les cycloadditions réalisées par une réaction utilisant un diénophile de type nitrosopyridine et catalysées par une source de cuivre chiral ont conduit aux cycloadduits précurseurs d’azaspirobicycles avec une énantiosélectivité modeste. D’autres cycloadditions utilisant un dienophile chiral de type chloronitroso dérivé du D-xylose ont permis la synthèse de précurseurs de bicycles oxaspiraniques avec des excès énantiomériques supérieurs à 95%. Cette dernière approche a permis la synthèse de spiroethers par une réaction d’ouverture de liaison N-O ainsi qu’une réaction de substitution nucléophile intramoléculaire, tandis que des spirolactones ont été obtenus par oxydation du diol résultant de l’ouverture de la liaison N-O. La fonctionnalisation de ces structures a été possible en engageant leur fonction vinyl triflate dans des couplages de Suzuki. Il a ainsi été possible de synthétiser 9 structures différentes oaxaspiraniques dont 5 de façons énantiosélectives. / During this research, we were interested in the synthesis of enantiopur heterospiranic bicycles. We therefore developed a new synthetic route towards the synthesis of molecules with different spirocyclic structures. This novel synthetic route features a nitroso Diels-Alder cycloaddition as key step. The total control of the stereoselectivity and the regioselectivity of the reaction, rarely described in the literature, have been specifically studied during this work. This study allows us to have a better understanding of this reaction. Two different approaches have been developed in this work. They both led to total control of the regioselectivity of this cycloaddition. Cycloadditions performed by reactions using a nitrosopyridine dienophile and catalyzed by a chiral source of copper allows the synthesis of cycloadducts precursor of azaspirocycles with a modest enantioselectivity. Cycloadditions using a chloronitroso chiral dienophile derived from xylose allowed the synthesis of oxaspiraniques precursors with enantioselective excess of at least 95%. The last approach was finally validated by the synthesis of various spiroethers and spirolactones through N-O bond cleavage an intramolecular cyclizations. Finally, the vinyl triflate function of the spirolactones and spiroethers was engaged in Suzuki couplings to introduce molecular diversity at a late stage allowing the synthesis of 9 different spiranic structures including 5 enantioenriched.

Made available in DSpace on 2016-12-23T14:33:32Z (GMT). No. of bitstreams: 1 Joao Olavo Baiao de Vasconcelos.pdf: 325868 bytes, checksum: 0459e6ca76a321095f4fc0d37ab23f21 (MD5) Previous issue date: 2011-12-21 / Petroleum Engineer activity is constantly enrolled on a series of optimization problems on many contexts, as, for instance, defining efficient and optimized projects on petroleum reserves development. However, there is an extreme difficulty on resolution of exploration and production (P&E) optimization problems, since they are often complex, with high degree of nonlinearity, presenting high uncertain number, and huge computational cost involved. Among them, there is the problem of determining the best throughput distribution among the wells of a petroleum production platform that achieves the biggest financial profitability of an E&P project, here named Petroleum Well Throughput Optimization Problem (PWTOP). In order to deal with PWTOP, some continuous optimization algorithms that deals with linearity restrictions present on the problem were studied, that are the Derivative Free Optimization (DFO), the Generating Set Search (GSS), and the Differential Evolution (DE). DFO is a sequential algorithm, whereas GSS and DE are parallel algorithms. Two case studies are also presented that represents synthetic petroleum fields. The results show how the studied algorithms behave on dealing with PWTOP for the two case studies, comparing experimental results obtained on optimized financial values, execution times and amount of objective function evaluation. Concludes, lastly, that, for the simplest case study, GSS had the best result, and for the most complex case study, more like real reservoirs, DE stood out / A atividade de Engenharia de Petróleo está rotineiramente envolvida em uma série de problemas de otimização em variados contextos, como definir projetos otimizados e eficientes na produção e no desenvolvimento de reservas de petróleo. Entretanto, há uma extrema dificuldade na resolução de problemas de otimização de exploração e produção (E&P), uma vez que são problemas frequentemente complexos, com elevado grau de não-linearidade, que apresentam alto número de incertezas e com enorme custo computacional envolvido. Dentre eles, está o problema de determinar a melhor distribuição de vazões entre os poços de uma plataforma de produção de petróleo capaz de resultar em um projeto de E&P de maior rentabilidade financeira, aqui denominado Problema de Otimização de Vazão de Poços de Petróleo (POVPP). Para tratar o POVPP, foram estudados alguns algoritmos de otimização contínua que possam lidar com as restrições lineares presentes no problema, que são o Otimização sem Derivadas (Derivative Free Optimization DFO), o Busca por Conjunto Gerador (Generating Set Search GSS) e o Evolução Diferencial (Differential Evolution DE). O DFO é um algoritmo sequencial, enquanto que o GSS e o DE são algoritmos paralelos. Também são apresentados dois estudos de caso que representam campos de petróleo sintéticos. Os resultados mostram como os algoritmos estudados se comportam ao tratar o POVPP para os dois estudos de caso, comparando-se dados obtidos de valores financeiros otimizados, tempos de execução e quantidade de avaliações da função objetivo. Conclui-se, por fim, que, para o estudo de caso simples, o GSS teve o melhor resultado, e para o estudo de caso mais complexo, mais semelhante a reservatórios reais, o DE se sobressaiu

<p>U doktorskoj disertaciji je prezentovano pedago&scaron;ko istraživanje koje se odnosi na teorijsko i eksperimentalno ispitivanje i proučavanje efekata primene kognitivno-vizuelnog pristupa zasnovanog na primeni grafičkih reprezentacija funkcija u obradi nastavnih sadržaja iz oblasti funkcija i njihovih primena. Na osnovu teorijskih principa kognitivno-vizuelnog pristupa, osmi&scaron;ljeni su i kreirani originalni didaktičko-metodički modeli za realizaciju sadržaja iz oblasti: matematičke analize (funkcije i izvod funkcije); problema sme&scaron;e (problemi me&scaron;anja rastvora); linearne funkcije i njene primene na re&scaron;avanje problema (problemi iz oblasti algebre, fizike i realnog okruženja). Ključni aspekti predloženog metodičkog pristupa su: vizuelizacija, vi&scaron;estruke reprezentacije, konceptualna znanja, postepeni prelazak ka vi&scaron;im nivoima apstrakcije u razvoju matematičkog m&scaron;ljenja, kao i planska i sistematska upotrebu računara sa odgovarajućom softverskom podr&scaron;kom. Okosnicu kognitivno-vizuelnog pristupa u obradi sadržaja matematičke analize i značajnu novinu u izučavanju izvoda funkcije predstavljaju zadaci sa grafičkim sadržajima i/ili zahtevima. Prikazane su metodičke mogućnosti ovih zadataka u kreiranju multireprezentativnog okruženja za učenje čija je polazna tačka formiranje i razvoj grafičkog razumevanja matematičkih koncepata. Takođe je izložena mogućnost klasifikacije zadataka sa grafičkim sadržajima i/ili zahtevima po različitim kriterijumima, na osnovu koje je data tipologija i razrađena metodika njihove primene u nastavnoj praksi.Sprovedeno je empirijsko istraživanje u okviru koga je u periodu od 2013. do 2015. godine realizovano pet pedago&scaron;kih eksperimenata sa paralelnim grupama u kojima su učestvovala 642 ispitanika (222 učenika četvrtog i 120 učenika prvog razreda gimnazije prirodno-matematičkog smera, 180 studenata osnovnih studija hemije i 120 studenata prve godine osnovnih studija fizike). Za potrebe istraživanja osmi&scaron;ljeni su i izrađeni nastavni materijali koji su omogućili učenicima/studentima eksperimentalnih grupa da izučavaju funkcije i njihove primene u multireprezentativnom i vizuelno-dinamičkom računarskom okruženju. Instrumenti primenjeni u istraživanjima bili su inicijalni i finalni testovi znanja. Evaluacija ostvarenih efekata primene kognitivno-vizuelnog pristupa, izvr&scaron;ena je poređenjem postignuća učenika/studenata eksperimentalnih (kognitivno-vizuelnih) i kontrolnih (tradicionalnih) grupa na testovima znanja. Na osnovu rezultata sprovedenih pedago&scaron;kih eksperimenata, utvrđeno je da primena kognitivno- -vizuelnog pristupa zasnovanog na grafičkom i dinamičkom prikazu funkcije u prezentovanju matematičkih sadržaja i re&scaron;avanju problema, u računarskom okruženju, ima značajan uticaj na kvalitet znanja učenika/studenata i ostvarenost optimalnih rezultata u učenju i razumevanju nastavnih sadržaja iz oblasti funkcija i njihovih primena na re&scaron;avanje problema.</p> / <p>In the doctoral dissertation a pedagogical research related to theoretical and experimental study of effects of applying a cognitive-visual approach based on the use of graphic representations of functions in interpretation of teaching contents from the field of functions and their applications is presented. On the basis of theoretical principles of cognitive-visual approach, original didacticmethodical models for the realization of contents were designed and created in the field: of mathematical analysis (functions and function derivative); problem of mixture (problems of mixing solutions); linear functions and its applications to solve problems (problems in the field of algebra, physics and the real environment). Key aspects of the proposed methodical approach are: visualization, multiple representations, conceptual knowledge, gradual transition to higher levels of abstraction in the development of mathematical thinking, as well as the planned and systematic use of computers with appropriate software support. The background of cognitive-visual approach in interpretation of mathematical analysis content and a significant novelty in the study of function derivative represent the problems with graphical contents and/or requirements. The methodological possibilities of these problems in creation of a multi-representative learning environment whose starting point is the formation and development of a graphical understanding of mathematical concepts are presented. The possibility of problems classification with graphical contents and/or requests according to different criteria is presented, on the basis of which, the typology is proposed and methodology for their application in teaching practice is elaborated. During the period 2013-2015 an empirical research was&nbsp; conducted within which five pedagogical experiments were realized with parallel groups involving a total of 642 respondents (222 students of the fourth and 120 first-year high school students major in science, 180 students of bachelor chemistry studies and 120 students of the&nbsp; first year of bachelor physics studies). For the purpose of the research, teaching materials that enabled students of the experimental groups to study the functions and&nbsp; their applications in a multi-representative and visual-dynamic computing environment were created. The instruments used in the research were initial and final tests of knowledge. The realized effects of the application of cognitive-visual approach was evaluated by comparing the achievements of high school students/ students of experimental (cognitive-visual) and control (traditional) groups on knowledge tests. Based on the results of the conducted pedagogical experiments, it has been established that the application of the cognitive-visual approach based on the graphical and dynamic presentation of the function in teaching mathematical contents and in problem solving in a computer environment has a significant impact on the quality of high school students&rsquo;/students&rsquo; knowledge and on the achievement of optimal learning outcomes and understanding of teaching contents from the field of functions and their application to solving problems.</p>

Micro-economic reform is a primary objective of modern Australian socio-economic policy. The key outcome targetted by this reform is increased efficiency, measured by a range of factors, including cost reduction, increased savings, and a more facilitative environment for business activity. These benefits are sought by the proponents of reform as part of a push to increase national prosperity, but concerns that social equity is undermined by it are expressed by opponents of that reform. The debate between efficiency and equity is raging in current Australian tax policy, a key site for micro-economic reform. As Government Budget restructuring occurs in Australia, demographic change (eg, the ageing population) undermines the ability of public funded welfare to provide retirement benefits. Responsibility for self-funded retirement is an important contributor to increasing private savings. Investment in growth assets such as corporate stock is increasing in Australia, however concerns about volatility of asset values and yield stimulate the importance of investment risk management techniques. Financial contract innovation utilising financial derivatives is a dominant mechanism for that risk management. Synthetic equity products which are characterised by capital protection and enhanced yield are popular and efficient equity risk management vehicles, and are observed globally, particularly in the North American market. Financial contract innovation, risk management using financial derivatives, and synthetic equity products suffer from an adverse tax regulatory response in Australia, which deprives Australian investors from access to important savings vehicles. The negative Australian tax response stems from anachronistic legislation and jurisprudence, which emphasises tax outcomes based on legal form. The pinnacle of this approach is the tax law insistence on characterisation of financial contracts as either debt or equity, despite some important financial similarities between these two asset types. Since derivatives produce transactions with novel legal forms this approach is unresponsive to innovation. The negative tax result also stems from a perception that the new products are tax arbitrage vehicles, offering tax benefits properly available to investment in stocks, which is thought to be inappropriate when the new products resemble debt positions (particularly when they are capital protected and yield enhanced). The negative tax response reflects administrative concerns about taxpayer equity and revenue leakage. This approach seeks to impose tax linearity by proxy: rather than utilising systemic reform to align the tax treatment of debt and equity, the current strategy simply denies the equity tax benefits to a variety of innovative financial contracts. It deprives Australians of efficiency enhancing savings products, which because of an adverse tax result are unattractive to investors. The weakness of the current approach is illustrated by critical analysis of three key current and proposed tax laws: the ???debt dividend??? rules in sec. 46D Income Tax Assessment Act 1936 (the ???Tax Act???); the 1997 Budget measures (which seek to integrate related stock and derivative positions); and the proposals in the Taxation of Financial Arrangements Issues Paper (which include a market value tax accounting treatment for ???traded equity,??? and propose a denial of the tax benefits for risk managed equity investments). The thesis develops a model for financial analysis of synthetic equity products to verify the efficiency claims made for them. The approach is described as the ???Tax ReValue??? model. The Tax ReValue approach isolates the enhanced investment returns possible for synthetic equity, and the model is tested by application to the leading Australian synthetic equity product, the converting preference share. The conclusions reached are that the converting preference share provides the key benefits of enhanced investment return and lower capital costs to its corporate issuer. This financial efficiency analysis is relied upon to support the assertion that a facilitative tax response to such products is appropriate. The facilitative response can be delivered by a reformulation of the existing tax rules, or by systemic reform. The reformulation of the existing tax rules is articulated by a Rule of Reason, which is proposed in the thesis as the basis for the allocation and retention of the equity tax benefits. To avoid concerns about taxpayer equity and revenue leakage the Rule of Reason proposes a Two Step approach to the allocation of the equity tax benefits to synthetics. The financial analysis is used to quantify non-tax benefits of synthetic equity products, and to predict whether and to what extent the security performs financially like debt or equity. This financial analysis is overlayed by a refined technical legal appraisal of whether the security contains the essential legal ???Badges of Equity.??? The resulting form and substance approach provides a fair and equitable control mechanism for perceived tax arbitrage, whilst facilitating efficient financial contract innovation. The ultimate source of non-linearity in the taxation of investment capital is the differential tax benefits provided to equity and debt. To promote tax linearity the differentiation needs to be removed, and the thesis makes recommendations for systemic reform, particularly concerning the introduction of a system of ???Franked Debt.??? The proposed system of ???Franked Debt??? would align the tax treatment of debt and equity by replacing the corporate interest deduction tax benefit with a lender credit in respect of corporate tax paid. This credit would operate mechanically like the existing shareholder imputation credit. The interface of this domestic tax credit scheme with the taxation of International investment capital, and the problems occasioned by constructive delivery of franking credits to Australian taxpayers via synthetics, are resolved by the design and costings of the new system, which has the potential to be revenue positive.

本研究的主要目的是探討會計師事務所審計人員對衍生性金融商品(DFI)的財務報導與查核能力，並分析可能影響此項能力的因素。另一目的則是希望探討審計人員對財務會計準則公報第二十七號的意見及看法，以及對這號公報的瞭解程度。本研究以問卷為蒐集資料的工具，在139份回收的問卷中，只有24位審計人員不知道什麼是DFI，約有九成的審計人員認為查核含有從事DFI交易公司之財務報表之審體審計風險較沒有從事此類交易的公司高。造成審計人員對DFI財務報導的認知程度差異的原因，經統計檢定後，有下列幾項： （1） 審計人員在事務所擔任的職位， （2） 審計人員認定衍生性金融商品的能力，以及 （3） 審計人員是否曾經查過衍生性金融商品。 造成審計人員對DFI財務報導查核能力差異的原因經統計檢定後，有下 列幾項： （1） 事務所的規模， （2） 審計人員之最高學歷， （3） 審計人員是否已取得會計師資格， （4） 審計人員在事務所擔任的職位， （5） 審計人員認定衍生性金融商品的能力， （6） 審計人員對衍生性金融商品的熟悉程度，以及 （7） 審計人員是否曾經查過衍生性金融商品。 審計人員是否曾查核過DFI並不會影響其對第二十七號公報的熟悉程度。此外，約三成的審計人員認為「各類商品之財務風險」與「商品之公平市價」是其依照此號公報查核DFI時最難決定之項目。至於審計人員如何驗證客戶在財務報表上所揭露關於DFI的公平價值，約各有三成的審計人員取得之方式為「採用公開市場之成交價」、「向銀行詢價」。 值得注意的是，在瞭解第二十七號公報的審計人員當中，只有約半數認為依照第二十七號公報揭露DFI，能幫助閱表者評估風險；同樣地，也只有半數的審計人員認為第二十七號公報能對他們在查核DFI時提供更明確的指引。審計人員是否曾經查核過DFI不會影響他們對這兩個問題的看法。 / In this study, the author investigated the degree of auditors' cognition and audit ability on derivative financial instruments (DFI) in Taiwan and he studied some factors that might affect these abilities. Besides, the author also investigated auditors' opinions of Statement of Financial Accounting Standard No. 27 in ROC. The author used questionnaire as a tool in gathering data. Factors that might affect auditors' cognition of DFI are as follows: (1) The current job position of auditors. (2) The auditors' abilities to recognize DFI. (3) The auditors' experiences of auditing DFI. Factors that might affect auditors' audit ability of DFI are as follows: (1) Firm size. (2) The highest education auditors received. (3) Whether they have got CPA license. (4) The current job position of auditors. (5) The auditors' abilities to recognize DFI. (6) The auditors' experiences of auditing DFI. (7) The extent of auditors' familiarity toward DFI. Auditors' opinions of Statement of Financial Accounting Standard No. 27 in ROC can be concluded as follows: (1) Only half of the auditors who understand this statement think it can help them to audit DFI related disclosures. (2) Whether auditors have audited DFI doesn't affect the extent of auditors' familiarity toward DFI. (3) "Financial risk" and " fair value of DFI" are two of the most difficult items to decide when auditors audit DFI.

自1970年代以後，匯率制度由「固定匯率制度」轉變為「浮動匯率制度」，貨幣政策由「利率管制誘導型」轉變為「貨幣供給量管制型」，而將利率交由市場決定。此種金融環境之變革，使企業為規避匯率及利率風險之風險，發展出許多新金融工具，「衍生性金融商品」乃應運而生。目前，衍生性金融商品在國際金融市場上扮演著不可或缺之角色。由於衍生性金融商品具有高槓桿及高風險的特性，利用衍生性金融商品固可達到交易、籌資、避險之目的，但若操作不當，其引起的損失亦不容輕忽。故操作衍生性金融商品時，應注意其相關之內部控制制度。本研究與瞭解企業操作衍生性金融商品之概況與內部控制情形，並進一步對其內部控制制度提出具體建議。研究方法以問卷調查台灣地區87年度操作衍生性金融商品之非金融業上市公司，樣本數為141份，回收67份，回收率為47.5%。 　　就操作概況而言，企業規模越大，操作衍生性金融商品之種類越多樣化，操作目的也趨向避險與非避險交互運用，此外，操作年數也越長。就內部控制情形而言，企業操作衍生性金融商品之控制環境、風險評估與控制活動、資訊與溝通及監督不會因產業別、資產總額、營業收入淨額、資本型態、對外投資狀況與國外貿易狀況之不同而有太大的差異。但在風險評估與控制活動方面，中外合資之企業於市場風險、信用風險及流動性風險上之表現較純本國投資之企業略佳，而在監督方面，有對外投資之企業較無對外投資之企業表現略佳。 　　在本研究可發現企業於操作衍生性金融商品時，對於應執行之控制政策與程序，幾乎都予以應有的注意並確實執行，這些內部控制政策與程序與公司特性間之關係並未非常顯著。可能原因之一為上市公司操作衍生性金融商品時，應遵循財政部之規定，訂定作業手冊並加以監督，故企業在此強制性之要求下，能維持一定品質之內部控制。可能原因之二為企業操作衍生性金融商品之金額通常不會太大，且交易目的多為避險，其性質較為單純，故可落實相關之內部控制制度。 / Since 1970, the exchange rate system has changed from "fixed rate" to "floating rate", and the monetary system has also changed. In order to avoid the risk of interest rate and exchange rate fluctuations, companies are increasingly using derivative financial instrument (DFI). Since DFI is fairly risky and could cause huge losses, companies must be very careful when using then. The internal controls for DFI is thus very important. This study investigates how companies use DFI and their related internal control systems. This research also provides suggestions for better internal controls for DFI. A questionnaire was used to gather data from the 141 lists firms at the Taiwan Stock Exchange, which are using DFI. The response rate is about 47.5%. (i.e., 67 questionnaires returned) 　　The results of the study are as follows: 　　(1) The larger the company is, the more kinds of DFI they are using and the longer it has been using DFI. 　　(2) The internal control systems are not significantly different with respect to company's industry type, total assets, net operating revenue, capital type and investment conditions. 　　(3) For risk assessment and control activities, joint-venture companies outperforms Taiwanese companies in managing market risk, credit risk and liquidity risk. In monitoring DFI, companies that have outside investments outperforms those that don't. 　　(4) Companies do follow internal control procedures when are using DFI. These control procedures are not significantly related to companies' characteristics. One of the possible reasons is that they are forced to follow regulations set by the Securities and Fu ture Commission. Another reason is the amount of DFI they transact is usually not large, therefore they can enforce their DFI-related internal control procedures.

Management and supply of water in an urban water distribution system is a complex process, which include various complexities like pressure variations across the network depending on topography, demand variations depending on customers’ requirement and unaccounted water etc. Applying automatic control methods to water distribution systems is a way to improve the management of water distribution. There have been some attempts in recent years to develop optimal control algorithms to assist in the operation of complex water distribution systems. The difficulties involved by these hydraulic systems such as non-linearity, and diurnal demand patterns make the choice of a suitable automatic control method a challenge. For this purpose, this study intends to investigate the applicability of different controllers which would be able to meet the targets as quickly as possible and without creating undue transients. As a first step towards application of different controllers, PD and PID linear controllers have been designed for pump control and valve control in water distribution systems. Then a Dynamic Inversion based nonlinear controller has been designed by considering the non-linearities in the system. Here, different cases considering the effects of initial conditions used, linearization methods used, time step used for integration and selection of gains etc., have been studied before arriving at best controller. These controllers have been designed for both the flow control problems and level control problems. It is found that Dynamic Inversion-based nonlinear controller outperforms other controllers. It is well known that the performance of controllers is much dependent on the tuning of the gains (parameters). Thus in this study various alternative techniques such as Ziegler--Nichols rules (ZNPID), Genetic algorithms (GAPID) and fuzzy algorithms (FZPID) have been studied and a comparative study has been made Although with all the three gain tuning methods, required states have reached their target values, but the responses vary much in reaching to final targets. The self-tuned FZPID controller outperforms other two controllers, especially with regard to overshoots and the time taken to tune the gains for each problem. Further, an optimal DI controller is developed for the over determined case with more controls and less targets. Energy loss is considered as an objective function and normal DI controller equations are considered as constraints. Hence, an attempt is made to reduce the energy minimization in water distribution system by formulating an optimal control problem using optimal Dynamic Inversion concept. Finally, leakage reduction model is developed based on excessive pressure minimization problem by locating valves optimally as well as by setting valves optimally. For this purpose, optimization problem is solved using Pattern search algorithms and hydraulic analysis is carried out using EPANET program.

Scale-invariant interest points have found several highly successful applications in computer vision, in particular for image-based matching and recognition. This paper presents a theoretical analysis of the scale selection properties of a generalized framework for detecting interest points from scale-space features presented in Lindeberg (Int. J. Comput. Vis. 2010, under revision) and comprising: an enriched set of differential interest operators at a fixed scale including the Laplacian operator, the determinant of the Hessian, the new Hessian feature strength measures I and II and the rescaled level curve curvature operator, as well as an enriched set of scale selection mechanisms including scale selection based on local extrema over scale, complementary post-smoothing after the computation of non-linear differential invariants and scale selection based on weighted averaging of scale values along feature trajectories over scale. A theoretical analysis of the sensitivity to affine image deformations is presented, and it is shown that the scale estimates obtained from the determinant of the Hessian operator are affine covariant for an anisotropic Gaussian blob model. Among the other purely second-order operators, the Hessian feature strength measure I has the lowest sensitivity to non-uniform scaling transformations, followed by the Laplacian operator and the Hessian feature strength measure II. The predictions from this theoretical analysis agree with experimental results of the repeatability properties of the different interest point detectors under affine and perspective transformations of real image data. A number of less complete results are derived for the level curve curvature operator. / <p>QC 20121003</p> / Image descriptors and scale-space theory for spatial and spatio-temporal recognition

Real estate represents a part of the portfolio of many investors and can be accessed from both the real and the financial market. The low efficiency of real market prevents from taking advantage of the value created through diversification. This value can be partially recovered substituting real assets by securitized assets such as REITs. The empirical study of both markets in Spain shows an insufficient supply of securitized assets and the inexistence of an organized market of real estate derivatives, leading to a lower efficiency compared to other countries where they do exist. The relationship between real and financial markets opens a way to study real estate bubbles. It also enables to identify the sources of real estate risks and the strategies for hedging it. A wide development of assets-securitization and derivatives is essential to manage real estate risk and to improve the efficiency of the real estate market. / La inversió immobiliària, que forma part de la cartera de molts inversors presenta una doble via d’accés: el mercat real i el mercat financer. La baixa eficiència del mercat real impedeix aprofitar el valor creat mitjançant la diversificació. Aquest valor es pot recuperar parcialment substituint actius reals per actius titulitzats, com per exemple els REITs. L’estudi empíric dels dos mercats a Espanya revela una oferta insuficient d’actius immobiliaris titulitzats i la inexistència d’un mercat organitzat d’actius derivats immobiliaris, provocant un nivell d’eficiència més baix, comparat amb d’altres països on sí que existeixen. La interrelació entre mercat real i financer obre una via per a l’estudi de la formació de bombolles. També ens permet identificar les fonts de risc immobiliari i proposar estratègies de cobertura. Un desenvolupament ampli dels actius titulitzats i dels instruments derivats és essencial per a la gestió del risc i per millorar l’eficiència del mercat immobiliari.

<p>Ved består huvudsakligen av tre typer av polymerer, cellulosa, hemicellulosa och lignin. Lignin bildas i naturen genom enzymatiskt initierad oxidativ koppling av tre olika typer av fenylpropan-enheter. Dessa bygger genom olika kol-kol- och kol-syre-bindningar upp en amorf tredimensionell polymer. När kemisk massa tillverkas bryts lignin ner och löses ut i kokluten. Luten innehåller de förbrukade kokkemikalierna och bränns generellt i en sodapanna för att regenerera kemikalierna och producera ånga. Sodapannan är emellertid dyr. Därför har den blivit produktionsbegränsande på många massabruk. Att avlägsna en del av ligninet från avluten vore därför önskvärt och att finna ekonomiskt intressanta produkter baserade på lignin från svartlut är därför ett viktigt forskningsområde .</p><p>Ett lämpligt område för ligninprodukter vore som tillsatts i oblekt massa. Oblekt massa används till stor del för tillverkning av kraftliner, topp- och bottenskikten på wellpapp. När lådor av wellpapp lagras i containrar som färdas över haven, förändras den relativa luftfuktigheten. Detta gör att lådorna kollapsar lättare än om de skulle ha lagrats vid konstant luftfuktighet, även en hög sådan. Detta är på grund av det så kallade mekanosorptiva- eller accelererade krypfenomenet. Genom tillsatts av våtstyrkemedel till kraftliner eller behandla den med hydrofoba ämnen, finns indikatoner på att mekanosorptiva effekten skulle kunna minska.</p><p>För att försöka minska den effekten har ett lågmolekylärt kraftlignin, som utvunnits med hjälp av tvärsflödesfiltrering av svartlut och svavelsyrafällning, använts. Genom derivatisering av detta lignin med linolja erhölls ett hydrofobt ligninderivat som uppvisar strukturella likheter med biopolymeren suberin. När detta suberinlika ligninderivat tillsätts till massa verkar det mekanosorptiva krypet minska. När lågmolekylärt lignin används tillsammans med ligninradikalinitiatorerna lackas eller mangan(III) i kraftlinermassa erhålls dessutom en våtstyrka på ca 5% av torrstyrkan. Efter aminering av detta lignin gav en tillsatts till kraftlinermassan en våtstyrka på upp till 10% av torrstyrkan. Det finns indikationer på att det mekanosorptiva krypet samtidigt minskar när dessa behandlingar görs som ger upphov till ökad våtstyrka.</p> / <p>Wood consists mainly of three types of polymers; cellulose, hemi cellulose and lignin. Lignin is formed in nature through enzymatic initiated oxidative coupling of three different kinds of phenyl propane units. These form by various carbon-carbon and carbon-oxygen bonds, an amorphous three-dimensional polymer. As chemical pulp is produced, lignin is degraded and dissolved into pulping liquors. These liquors contain the spent cooking chemicals and are generally burnt in a recovery boiler to regenerate cooking chemicals and produce steam. However, the recovery boiler is expensive. Hence, it has become the bottleneck for production in many pulp mills. Removal of some lignin from the spent cooking liquor would, for that reason, be desired and valuable products based on lignin from cooking liquors are searched for.</p><p>One suitable area for lignin products would be as additive in unbleached pulp. A major product from unbleached pulp is kraftliner, the top and bottom layers of corrugated board. When boxes of corrugated board are stored in containers travelling overseas the relative humidity is varying. This makes the boxes collapse more easily than if they were stored at constant humidity, even a high one. This is due to the so called mechano-sorptive or accelerated creep phenomenon. By addition of wet strength additive to kraftliner or treating it with hydrophobic compounds there are indications on that the mechano-sorptive effect would decrease.</p><p>Trying to decrease this effect, low molecular weight kraft lignin has been used. It was obtained by cross-flow filtration of black liquor and precipitation by sulphuric acid. By derivatisation of this lignin by linseed oil, a hydrophobic lignin derivative was obtained, similar in structure to units in the biopolymer suberin. As this suberin-like lignin-derivative was added to pulp the mechano-sorptive creep seemed to be lowered. Furthermore, when the low molecular weight lignin was used together with the lignin radical initiators laccase or manganese(III) in kraftliner pulp, a wet strength of about 5% of dry strength was obtained. An amination treatment of this lignin and addition to kraftliner pulp resulted in a wet strength of up to 10% of dry strength. There are indications of that the mechano-sorptive creep also decreases as these treatments, resulting in increased wet strength, are made.</p>