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Bednář, Martin. "Automatické testování projektu JavaScript Restrictor." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2020. http://www.nusl.cz/ntk/nusl-432879.
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The aim of the thesis was to design, implement and evaluate the results of automatic tests for the JavaScript Restrictor project, which is being developed as a web browser extension. The tests are divided into three levels - unit, integration, and system. The Unit Tests verify the behavior of individual features, the Integration Tests verify the correct wrapping of browser API endpoints, and the System Tests check that the extension does not suppress the desired functionality of web pages. The System Tests are implemented for parallel execution in a distributed environment which has succeeded in achieving an almost directly proportional reduction in time with respect to the number of the tested nodes. The benefit of this work is detection of previously unknown errors in the JavaScript Restrictor extension and provision of the necessary information that allowed to fix some of the detected bugs.
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Dollhopf, Matthew John. "NASCAR RESTRICTOR PLATE EXHAUST MANIFOLD DESIGN STRATEGIES." Master's thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4456.
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This paper presents the results of a study on exhaust manifold design for a NASCAR Restrictor plate internal combustion engine. A computer simulation model was developed using Ricardo WAVE software. WAVE is a computer-aided engineering code developed by Ricardo to analyze the dynamics of pressure waves, mass flows and energy losses in ducts, plenums and the intake and exhaust manifolds of various systems and machines. [1] The model was validated against experimental data from a current NASCAR Winston Cup restrictor plate motor. The parameters studied have been exhaust manifold diameters and lengths. A response surface analysis of the simulation output followed. The analysis of results shows the design parameters of the existing exhaust manifold are not optimized. The findings from these studies are used to derive exhaust system design guidelines which define optimum exhaust system geometry to maximize average Brake Horsepower over a given powerband for a restrictor plate NASCAR engine.M.S.
Department of Industrial Engineering and Management Systems
Engineering and Computer Science
Industrial Engineering and Management Systems
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Tao, Fuyang. "Experimental study of restrictor noise in ventilation duct systems." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/398630/.
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Single-hole restrictors are widely used in the aircraft air distribution system (ADS). The noise generated due to the flow passing over the restrictor is a main interior noise source of the cabin. Prediction of the restrictor noise generation is important for a quite ADS design. This work experimentally and analytically studies the noise generation mechanisms of the single-hole restrictor. An experimental rig to investigate the restrictor self-noise and interaction noise generated by the turbulent wake produced by in-duct elements installed in the duct and impinging on the restrictor has been developed and constructed. Aeroacoustic measurements of the restrictor self-noise have been made both inside and in the far field of the duct. Two models have been developed to understand the restrictor noise generation mechanisms and predict the sound power level (PWL). One model is based on the surface pressure cross spectrum to compute the effective axial dipole distribution. The other is an extension of previous work and based on the static pressure drop across the restrictor. The restrictor dimension is shown to have a large effects on the restrictor noise generation. For the interaction noise generation, the important parameters including mean flow speed, restrictor dimension, turbulence level and characteristic length, that determine the sound power radiation spectrum are studied. A semi-empirical model has been developed to predict the sound power spectrum due to interaction noise. The link between the interaction noise generation and the restrictor surface pressure has been investigated. In addition to the investigation of the restrictor noise generation, this work conducted a short study into the use of surface roughness on the upstream side of the restrictor to reduce the noise generation whilst maintaining the pressure drop across it. It is shown that the noise generation can be reduced above the first cut-on frequency of the duct by increasing the upstream surface roughness.
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Lindley, Dustin. "Design and Optimization of a Throttle and Restrictor for Formula SAE." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1346171359.
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Švancár, Matúš. "Přenos bezpečnostních opatření z prohlížeče Brave do rozšíření JavaScript Restrictor." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2021. http://www.nusl.cz/ntk/nusl-445495.
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Users of internet browsers are constantly monitored, without their consent. By using the JavaScript APIs, it is possible to obtain various information about the browser, which together form a browser fingerprint, which can then be misused. Therefore, the goal of this work is to use a robust fingerprint protection solution of Brave browser and port it to the JavaScript Restrictor extension. In this work, the problematics of obtaining an fingerprint and countermeasures in the Brave browser are analyzed and then compared with the current protection in the JSR extension. The method of porting of Brave's countermeasures is presented and subsequently the procedure of implementation of these defense elements into the browser extension is described. The resulting implementation has been tested and evaluated, with the new protection appearing to be effective.
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Stone, Mark Adam. "Improving Off-line and On-line Supercritical Fluid Extraction Techniques by Elevating the Post-Restrictor Pressure." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/26623.
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The high flow rate that results as fluid decompresses through the restrictor is arguably the single greatest problem with supercritical fluid extraction techniques. As a result of these high flow rates, solvent trapping is not efficient in many cases, and the more complicated sorbent trapping technique must be used. In addition, loss of the collection solvent may occur during the process making it difficult to work with small volumes, which are desirable from the standpoint of sensitivity, cost, and environmental concerns.
Similarly, these high decompressed flows have made it difficult to directly interface supercritical fluid extraction methods with separation techniques. This is unfortunate as supercritical extractions are ideal for on-line coupling in other respects, such as the fact that the fluid becomes gaseous upon depressurization and that supercritical fluids generally extract less contaminant material. In this thesis we have shown that, by elevating the post-restrictor pressure, the decompressed flow rate can be reduced, and these problems can be minimized, considerably.
Off-line trapping becomes much simpler when working at elevated pressures as the need for sorbent trapping is virtually eliminated and solvent trapping may be conducted with much less difficulty.
Elevated post-restrictor pressures were found to be very beneficial for on-line work as well. SFE/GC was carried out with complete transfer of the extraction effluent to a capillary GC column, which has not previously been demonstrated. Likewise the use of an open-tubular column interface, maintained at moderately elevated pressures, allowed SFE/HPLC to be conducted with quantitative analyte transfer, even in the presence of 10% modifier. In all cases - but especially for the on-line methods - more practical extraction parameters were possible, including extraction vessel volume, extraction flow rate, and dynamic extraction time.
Another benefit of elevating the post-restrictor pressure is that higher extraction flow rates will generally be possible. The benefits of this were not evaluated in the research presented here, however, the effect that the extraction flow rate can have on extraction time is considered, from a theoretical standpoint, in Chapter five.Ph. D.
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Chládek, Martin. "Výroba jezdce." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230449.
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Slider is a part of turn restrictor mechanism designed by company TOKOZ a.s. It is a part with complicated form and small dimensions from material DC04 (equivalent according to Czech standard ČSN 11 305.21). As the most suitable option for part manufacturing was chosen cutting and bending in progressive die. A design of forming layout with 11 stations was made and considering the outcomes of related calculations preliminarily selected presses LEXN 100 and Kaiser KSTU 1600. Subsequently was designed one row progressive die. Based on this designs were made few variants of part price calculations according to TOKOZ company customs. According to price calculation outcomes was as the most suitable selected press Kaiser KSTU 1600.
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Řehák, Ivo. "Návrh sacího traktu pro vůz Formule SAE." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228026.
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Thesis is bend on design of intake manifold for car Formula SAE. For driving of this car is used engine Yamaha YZF R6 (2005). Design of intake tract is processed so that agrees with rules and specifications for cars Formula SAE. For restriction of engine performance is in intake tract installed restrictor. For filling efficiency uplift of engine is used the resonance effect in intake pipes. Analysis of flow is carry out on simulation software for analyses of one dimensional flow.
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Pavličík, Lukáš. "Sací potrubí jednoválcového motoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231694.
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The aim of this diploma thesis is to create a thermodynamic computational model of a single cylinder IC engine for the Formula SAE car. The single cylinder SI engine KTM 500 EXC is considered as a powertrain unit. The intake manifold of the serial enduro motorcycle is modified according to the Formula SAE 2014 rules. Analysis of the one dimensional flow is performed by using Lotus engine simulation software.
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Adámek, Ladislav. "Zvýšení pružnosti zážehového jednoválcového motoru formule Student." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229714.
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Diplomová práce je zaměřena na konstrukční návrh sacího potrubí pro vůz Formula Student. Pro pohon vozu je použit jednoválcový atmosférický benzinový motor Husaberg FE 570. Sací potrubí je navrhováno tak, aby bylo v souladu s pravidly Formula Student. Pro zvýšení plnící účinnosti sací potrubí využívá resonančního efektu. Délky sacího potrubí byly spočítány v software Lotus Engine simulation.
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Huber, Hillary. "Aggressive Behavioral Phenotype in Intrauterine Growth Restricted (IUGR) Baboons Exposed to Moderate Nutrient Restriction Early in Development." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/dissertations/824.
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The thrifty phenotype hypothesis proposes reduced nutrition alters the trajectory of development of metabolic regulatory systems to produce a phenotype better fitted to an environment of decreased later-life nutrient availability. Because organisms have physiological mechanisms for coping with poor nutrition, they may have sociobehavioral mechanisms as well. Aggressive behavior, especially in the context of feeding competition, may be advantageous in such environments. There could be an association between aggression and intrauterine growth restriction (IUGR), which can result from low maternal food intake during pregnancy. The main hypotheses of this study are [1] IUGR offspring demonstrate higher rates of aggressive behavior and [2] IUGR offspring attain higher ranks. Behavioral observations were conducted on 22 juvenile baboons (Papio sp., ages 3-5 yrs) living in groups. Male IUGR (n = 4) and female IUGR (n = 5) were offspring of mothers fed 70% the same feed eaten by control (CTR) mothers in pregnancy and lactation. CTR males (n = 8) and CTR females (n = 5) were offspring of mothers fed ad libitum. Some authorities recommend this moderate level of dietary restriction for health and longevity. Offspring have not experienced dietary restriction since weaning. IUGR, compared to CTR, showed significantly increased rates of aggressive behavior, especially threat displays. Differences were more dramatic in males than in females. IUGR baboons performed the affiliative display behaviors lipsmack and chatter at elevated rates too, perhaps to counteract the effects of increased aggressive displays. IUGR females exhibited increased rates of stereotypical chewing behavior, while IUGR males exhibited decreased rates of play behavior, possibly indicating elevated anxiety levels. There was only limited support for condition-based differences in rank. Elevated rates of aggression in IUGR baboons may reflect an aggressive behavioral phenotype that enhances fitness by improving access to resources. Alternatively, they could be a non-adaptive result of neurodevelopment with a potentially negative impact on fitness. Unraveling the dynamic relationship between experiences and development is essential for understanding how phenotypes are formed. This will improve the ability of mothers to assess benefits of different nutritional strategies, leading to healthier individuals not just during growth and development, but throughout life.
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Timko, Martin. "Vylepšení rozšíření pro omezení volání JavaScriptu." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2019. http://www.nusl.cz/ntk/nusl-403180.
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The purpose of this thesis is to functionally expand the browser extension prototype created by Ing. Zbyněk Červinka, focused on the privacy protection of the user during his web browsing. Acquired facts about the function of existing tools for safety and privacy protection, such as technology JavaScript Zero, were used in the solution, which was created by employing a technique of encapsulating JavaScript objects and functions. This allows greater anonymity and safety for users during web browsing. The extension was tested and published under the title JavaScript Restrictor. The main benefit of this thesis is the increase of safety from attacks and increase of anonymity linked to the user data harvesting.
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Pohner, Pavel. "Detekce podezřelých síťových požadavků webových stránek." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2020. http://www.nusl.cz/ntk/nusl-417225.
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The purpose of this thesis is to prevent websites located in public internet from accessing user's internal network through web browser. Acquired knowdledge about modern browser's security mechanism - same-origin policy and options of implementing the web browser extensions using WebExtensions, was used in the solution. Proposed solution is based on WebRequest API, which intercepts and modifies HTTP requests, and extends functionality of existing browser extension JavaScript Restrictor with the ability to detect and prevent the browser to be abused as a proxy for scanning and accessing user's internal network. The implemented solution was tested and accepted as a part of JavaScript Restrictor. The main benefit of this thesis is the protection from possible abusement of a web browser as a proxy, which is not present in existing extensions.
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Saloň, Marek. "Detekce metod zjišťujících otisk prohlížeče." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2021. http://www.nusl.cz/ntk/nusl-445521.
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The main goal of this thesis is to design and implement a mechanism that provides protection against stateless tracking with browser fingerprint. Implemented tool has a form of module that takes part of JavaScript Restrictor extension. The module allows to specify heuristics used for evaluation of visited sites that may contain browser fingerprint extraction. If suspicious activity is detected, all subsequent HTTP requests from that site are blocked to prevent the extracted fingerprint from being sent to the server. The implementation and defined heuristics were tested. The resulting module represents an effective tool against stateless tracking. The main limitation of the implementation is possible corruption of sites by blocking HTTP requests.
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Hind, Hugh Robert Faulkner. "Restricted edge-colourings." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279728.
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May, Barnaby C. H. "Conformationally restricted peptidomimetics." Thesis, University of Canterbury. Chemistry, 2000. http://hdl.handle.net/10092/6083.
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Peptidomimetic compounds are becoming increasing important as medicinal agents. This thesis describes the design and synthesis of a novel class of non-hydrolysable peptidomimetic isosteres, the tetrazole-based amide bond isosteres. These new structural mimics have been developed for incorporation into enzyme inhibitors and biological probes where a non-hydrolysable cis- amide bond mimic is required.
Chapter one provides a general outline of conformational restriction and how this concept has been advantageously applied to the design of bioactive peptidomimetics. Conformational restriction, when used to pre-organise peptidomimetic ligands into a desired bioactive conformation, gives ligands that bind to target receptors with a greater affinity. The tetrazole heterocycle has obvious structural similarities to the cis-conformation of the amide bond and has been used to lock amide bonds in an equivalent conformation. Hence, the 1,5-disubstituted tetrazole ring is a popular constrained, planar
cis- amide bond mimic and its use as such is reviewed in chapter one.
Chapter two outlines the design of the tetrazole-based isosteres, the α-methylene tetrazole (2.5.1), α-hydroxymethylene tetrazole (2.5.2), and α-keto tetrazole isostere (2.5.3). The tetrazole-based isosteres incorporate the design features of a non-hydrolysable amide bond isostere and the conformational restriction of the 1,5-disubstituted tetrazole ring, to generate the first examples of non-hydrolysable tetrazole-based cis- amide bond mimics.
Chapter three reviews the synthesis of N-Z-(2RS,3S)-3-amino-2-hydroxy-4-phenylbutanoic acid [N-Z-AHPBA, 3.1.1], a key amide bond isostere used in potent protease inhibitors and a synthetic building block of the α-hydroxymethylene tetrazole isostere (2.5.2). We have investigated the synthesis of 3.1.1 by functionalisation of N-Z-L- phenylalaninal, 3.2.3. Due to shortcomings in this published procedure we have developed a new, generally applicable synthesis of this important amide bond isostere by hydroxylation of an enolate derived from methyl (3S)-N-Z-3-amino-4-phenylbutanoate
(3.4.2) with the oxodiperoxymolybdenum (pyridine) (hexamethyl phosphoric triamide) complex (MoOPH).
Chapter four describes the synthesis and spectral analysis of diastereomeric tetrazole-based compounds. We have synthesised two series of α-methylene tetrazolebased compounds, 4.1.4a-4.1.7a and 4.1.4b-4.1.7b, derived from L-alanine and D-alanine, respectively. We have used this analysis to establish trends in the 1H and 13C NMR of the diastereomeric series as an aid to the assignment of configuration of tetrazole-based ligands. We have also been able to monitor epimerisation of the C6 stereocentre adjacent to the tetrazole by 1H NMR under the conditions of peptide coupling.
Chapter five outlines the synthesis of (2S)-1-(benzyl ethanoate)-5-[2-(N-benzyloxycarbonylamino)-3-phenylpropane]-tetrazole, 5.2.1, an α-methylene tetrazolebased dipeptide mimic. We have incorporated 5.2.1 into extended substrate sequences of HIVp and tested these compounds for in vitro activity against HIVp. The modestly potent HlVp inhibitors 5.4.1, 5.4.2, and 5.4.3 represent a step-wise elongation of the C-terminal, and gave IC50 values against HIVp of 94 µM, 47 µM and 18 µM, respectively.
Chapter six describes the synthesis of the α-keto tetrazole isostere, by direct alkylation of (1RS,2S)-5-[2-(N-tert-butyloxycarbonylamino)-1-hydroxyl-3-phenylpropane]-1H-tetrazole, 6.3.13, with benzyl bromoacetate, followed by a TEMPO oxidation. The desired 1,5-disubstituted dipeptide mimic, (2S)-1-(benzyl ethanoate)-5-[2-(N-tert-butyloxycarbonylamino)-1-oxo-3-phenylpropane]-tetrazole, 6.3.16, was isolated from the 2,5-disubstitiuted dipeptide mimic, (2S)-2-(benzyl ethanoate)-5-[2-(N-tertbutyloxycarbonylamino)-1-oxo-3-phenylpropane J-tetrazole, 6.3.17. This outlines a new and generally applicable synthesis of the tetrazole-based isosteres.
Chapter seven describes the solid state structures of three tetrazole-based dipeptide mimics. The α-methylene tetrazole based isostere has been observed in the X-ray structure of the dipeptide mimic, (2S)-1-(benzyl ethanoate)-5-[2-(N-benzyloxycarbonylamino)-3-phenylpropane]-tetrazole and the cyclic tetrazolodiazepine analogue, cyclo-{[(2S)-5-(2-amino-3-phenylpropane)-1-ethanamide] tetrazole}, These are the first examples of the solid state structure of the α-methylene tetrazole isostere. We have also observed the solid state structure of the 2,5-disubstituted tetrazole, (2S)-2-(Benzyl ethanoate )-5-[2-(N-tertbutyloxycarbonylamino)-1-oxo-3-phenylpropane]-tetrazole, 6.3.17.
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li, sijia. "Perfection and Restriction." Thesis, Konstfack, Ädellab, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-7224.
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The paper talks about the topic of pursuing the perfect body and how we are controlled by the standards of per- fections. I chose this topic because of the development of the Chinese gym industry and personal experience . Many people try to pursue the standards of perfect bodies and use these standards to define themselves. Most people take it for granted that our bodies should look a certain way. In this paper, I want to question these standards and raise people’s awareness of the image of their bodies. I will also talk about my opinions about bodies. In my practical work, I mix different metals with different values into one piece and shape the material into vessel forms. I use the material and the forms to question perfections and the attitude towards bodies in the society . Then I make the vessels into jewelry pieces to discuss how our bodies are treated as jewelry . I use my jewelry works to question what our bodies are and help people see their bodies in a different perspective.
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Pagin, Peter. "Vagueness and Domain Restriction." Stockholms universitet, Filosofiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-68416.
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This paper develops an idea of saving ordinary uses of vague predicates from the Sorites by means of domain restriction. A tolerance level for a pred- icate, along a dimension, is a difference with respect to which the predicate is semantically insensitive. A central gap for the predicate+dimension in a domain is a segment of an associated scale, larger than this difference, where no object in the domain has a measure, and such that the extension of the predicate has measures on one side of the gap and the anti-extension on the other. The domain restriction imposes a central gap.Author count: 1;
Vagueness and Context Factors
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Fürst, Maximilian [Verfasser]. "Restricted matchings / Maximilian Fürst." Ulm : Universität Ulm, 2019. http://d-nb.info/1190178249/34.
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Daniels, Lucy Elizabeth. "The SgrAI restriction endonuclease." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393877.
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Ramsey, Priscilla W., J. Cathelyn, B. Gugliotta, and L. Lee Glenn. "Restricted Versus Open ICUs." Digital Commons @ East Tennessee State University, 2000. https://dc.etsu.edu/etsu-works/7529.
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Lewis, John Robert. "Bayesian Restricted Likelihood Methods." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407505392.
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Persson, Johan. "Restricted Region Exact Designs." Thesis, Linköpings universitet, Matematiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138614.
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Problem statement: The D-optimal design is often used in clinical research. In multi-factor clinical experiments it is natural to restrict the experiment's design space so as not to give a patient the combination of several high dose treatments simultaneously. Under such design space restrictions it is unknown what designs are D-optimal. The goal of the thesis has been to find D-optimal designs for these design spaces. Approach: Two new algorithms for finding D-optimal designs with one, two or three factors with linear models has been developed and implemented in MATLAB. Two restricted design spaces were explored. In cases when the program could not find the D-optimal design an analytic approach was used. Results: Special attention was given to the two factor model with interaction. All of the D-optimal designs for this model, N less or equal to 30, and their permutations have been listed as well as their continous designs. Conclusion: In one of the restricted design regions a simple design pattern appeared for N greater than or equal to 7. In the other restricted design region no obvious pattern was found but its continuous design could be calculated through analysis. It turned out that the number of trials at the lowest dose combination did not change when moving from the full space design to the restricted design regions.Frågeställning: D-optimala designer är vanliga i kliniska studier. När flera faktorer (läkemedel) prövas samtidigt kan det vara nödvändigt att begränsa försöksrummet så att patienterna undviker att få en hög dos av flera faktorer samtidigt. I sådana begränsade försöksrum är det okänt vilka designer som är D-optimala. Uppsatsens mål har varit att hitta D-optimala designer i begränsade försöksrum. Metod: Två nya algoritmer för att hitta D-optimala designer med en, två eller tre dimensioner och linjära modeller har utvecklats och implementerats i MATLAB. Två begränsade försöksrum har utforskats. I de fall då MATLAB-programmet inte kunde hitta de D-optimala designerna användes analytiska metoder. Resultat: Analys av en tvåfaktormodell med interaktion utforskades särskilt noggrant. Alla D-optimala designer och permutationer av dessa i de båda begränsade försöksrummen har listats för alla N mindre än eller lika med 30, samt även deras kontinuerliga designer. Slutsats: För det ena försöksrummet upptäcktes ett mönster i designen då N är större än eller lika med 7. I det andra försöksrummet upptäcktes inget mönster och det krävdes således analytiska metoder för att finna dess kontinuerliga design. Det visade sig att antalet försök i den lägsta doskombinationen förblev oförändrat då man bytte från det fulla designrummet till de båda begränsade designrummen.
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Brass, Stefan. "Range restriction for general formulas." Universität Potsdam, 2010. http://opus.kobv.de/ubp/volltexte/2010/4152/.
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Deductive databases need general formulas in rule bodies, not only conjuctions of literals. This is well known since the work of Lloyd and Topor about extended logic programming. Of course, formulas must be restricted in such a way that they can be effectively evaluated in finite time, and produce only a finite number of new tuples (in each iteration of the TP-operator: the fixpoint can still be infinite). It is also necessary to respect binding restrictions of built-in predicates: many of these predicates can be executed only when certain arguments are ground. Whereas for standard logic programming rules, questions of safety, allowedness, and range-restriction are relatively easy and well understood, the situation for general formulas is a bit more complicated. We give a syntactic analysis of formulas that guarantees the necessary properties.
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Sollazzo, Rhoda Jane. "The finite field restriction problem." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36900.
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This work studies the extension problem for subsets of finite fields. This remains an important unsolved problem in harmonic analysis, in both the Euclidean and finite field setting. We survey the partial results obtained to date, common techniques, and open conjectures. In the case of a homogeneous variety H over a d-dimensional finite field, the L² to L⁴ boundedness is proved whenever H contains no hyperplanes. This is accomplished by proving an incidence theorem for cones of this type, and applying a sufficient condition for L² to L²m obtained by Mockenhaupt and Tao in their 2004 introductory paper. We moreover present counterexamples for particular cones when Γ<4, establishing the 2 to 4 bound as optimal in Γ for general homogeneous varieties.
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Turner, Hazel L. "Stereocontrol in rotationally restricted ureas." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505382.
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Atropisomerism is a property exhibited by molecules where rotation about one or more bonds is restricted. Along with the biaryls, which are widely utilised in asymmetric catalysis most famously by BINAP and BINOL, several other classes of compounds display atropisomerism, primarily aiiilides, benzamides and biaryl ethers. These molecules have applications in enantioselective synthesis, asymmetric catalysis and been used to relay stereochemical information (Chapter 1). This thesis presents a new family of non-biaryl type atropisomers; rotationally restricted diarylureas. Chapter 2 explains how these aromatic ureas can be ring selectively functionalised using regioselective N-alkylation and directed ortho metalation. The chapter also describes how we have used these methodologies to synthesise some diastereomeric atropisomers. Chapter 3 reports the lateral lithiation of some diarylureas to yield diastereomeric atropisomers stereoselectively. We go on to show that, in these reactions, the sense of the diastereoselectivity is electrophile dependent. Several reaction pathways exist in lithium substitution sequences and Chapter 4 describes these routes and our attempts to use (-)-sparteine in laterallithiation reactions to determine the configurationally integrity of our organolithium. s . Finally, our efforts to synthesise some enantioenriched atropisomers from the diarylurea family using chiral sulfoxides is described in Chapter 5. This chapter also describes how an enantioenriched atropisomer is obtained using a kinetic resolution.
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Sapsed, Jonathan. "Restricted vision : strategizing under uncertainty." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313942.
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Fasulo, Daniel. "Algorithms for DNA restriction mapping /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/7020.
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Wilstermann, Michael. "Synthesis of conformationally restricted oligosaccharides." Lund : Dept. of Organic Chemistry 2, Lund University, 1997. http://catalog.hathitrust.org/api/volumes/oclc/39751534.html.
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Alakuijala, A. (Anna). "Branding in temporally restricted campaigns." Master's thesis, University of Oulu, 2014. http://urn.fi/URN:NBN:fi:oulu-201406101710.
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The importance of branding has been recognized for a long time in the business. During the last decades also other areas have utilized branding. Usually brands are connected to the long-term value, but there are several business situations where brands are used in temporally restricted conditions. Examples of those are single or recurrent branded campaigns. Varied temporal dimensions have been used in the business research. However, there is no much research on branding from the temporality point of view.
The aim of this study is to better understand branding in campaigns, which have temporal restrictions. The phenomenon is approached from three directions. At first, there are studied different brand definitions. In this study the brand is understood as social and dynamic interaction process among stakeholders. Through this process, differentiating attributes and added value are associated with the brand. Another aspect is the temporality theory. In addition to standardized and horizontal time, also episodic and vertical time dimensions are concerned. These are merged with the brand definition to provide the theoretical framework. The brand is added to the temporal view as a process containing events, which are points of vertical dimension, brand interaction.
The third approach is through the context of this study, health and political campaigns. They are selected because of their different temporal nature. Health campaigns represent usually single, non-recurrent campaigns, while political campaigns are cyclic and periodic. The campaigns are studied conducting the integrative literature research. The systematic process of searching and evaluating articles is followed by the thematic analysis. The analysis is based on themes included to the theoretical framework: brand, interaction among stakeholders and temporality.
The findings of this study show that branding in temporally restricted campaigns is done in phases. There are different objectives and forms of the brand interaction in the each phase. The study also provides a classification for stakeholders for describing different interaction in the phases. Different stakeholder groups participate to brand interaction during the pre- and post-campaign periods, while all groups are participating during the campaign period. The campaign related events can be divided to major and minor. The major events define the periods and the phases of the campaigns, while minor events occur during the periods, but are affecting to the brand.
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Wang, Hong Ph D. Massachusetts Institute of Technology Department of Mathematics. "A restriction estimate in R³." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122176.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, 2019Cataloged from PDF version of thesis.
Includes bibliographical references (page 87).
In this thesis, I proved a restriction estimate for paraboloid in R³ based on the polynomial partitioning method introduced by Larry Guth and the "two ends argument" introduced by Wolff and Tao.
by Hong Wang.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Mathematics
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Svoboda, Jiří. "Multi-modální "Restricted Boltzmann Machines"." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-236426.
Full textAbstract:
This thesis explores how multi-modal Restricted Boltzmann Machines (RBM) can be used in content-based image tagging. This work also cointains brief analysis of modalities that can be used for multi-modal classification. There are also described various RBMs, that are suitable for different kinds of input data. A design and implementation of multimodal RBM is described together with results of preliminary experiments.
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Hambrook, Kyle David. "Restriction theorems and Salem sets." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54044.
Full textAbstract:
In the first part of this thesis, I prove the sharpness of the exponent range in the L² Fourier restriction theorem due to Mockenhaupt and Mitsis (with endpoint estimate due to Bak and Seeger) for measures on ℝ. The proof is based on a random Cantor-type construction of Salem sets due to Laba and Pramanik. The key new idea is to embed in the Salem set a small deterministic Cantor set that disrupts the restriction estimate for the natural measure on the Salem set but does not disrupt the measure's Fourier decay. In the second part of this thesis, I prove a lower bound on the Fourier dimension of Ε(ℚ,ψ,θ) = {x ∊ ℝ : ‖qx - θ‖ ≤ ψ(q) for infinitely many q ∊ ℚ}, where ℚ is an infinite subset of ℤ, Ψ : ℤ → (0,∞), and θ ∊ ℝ. This generalizes theorems of Kaufman and Bluhm and yields new explicit examples of Salem sets. I also prove a multi-dimensional analog of this result. I give applications of these results to metrical Diophantine approximation and determine the Hausdorff dimension of Ε(ℚ,ψ,θ) in new cases.Science, Faculty of
Mathematics, Department of
Graduate
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Althorpe, Nicola Jayne. "Plasmid-mediated restriction evasion mechanisms." Thesis, University of Leicester, 1999. http://hdl.handle.net/2381/30313.
Full textAbstract:
Plasmid ColIb-P9 (Incll) encodes mechanisms which allow it to avoid destruction by type I and type II restriction enzymes during transfer by conjugation between strains of Escherichia coli. A genetic system was developed to analyse these mechanisms. The system relied on measuring Collb-mediated rescue of the restriction-sensitive plasmid R751 (IncPp) from destruction by EcoKI (type I) and EcoRI (type II). One Collb mechanism was known to involve a plasmid-encoded antirestriction gene known as ardA, the product of which is active against type I enzymes. Tests for alleviation of EcoKI restriction of R751, showed strong protection by a co-transferring Collb (Ard+) plasmid, slight protection when Collb was resident in the recipient and no effect when Collb was immobilised in the donor by removal of its nic site. Hence, expression of ardA is activated in the recipient cell following transfer no detectable transfer of the ArdA protein occurs from the donor to the recipient. The ardA gene is found in the leading region of Collb, which is defined as the first segment of the plasmid to enter the recipient cell during conjugation. Nucleotide sequencing of 11.7 kb of this region identified ten open reading frames. Furthermore, the region also contains three dispersed repeat sequences homologous to a novel single-stranded DNA promoter described by Masai and Arai (1997, Cell 89, 897-907). It is proposed that these secondary structures form in the transferring T-strand of Collb and function as promoters for transcription of genes encoded on the unique plasmid strand transferred during conjugation. Another mechanism, which acts independently of ardA, alleviates restriction of both type I and type II enzymes in the recipient in second or subsequent rounds of transfer. Two separate mechanisms appear to be operating since alleviation of type I restriction occurs in trans and is constitutive. In contrast, alleviation of type II restriction is by a czs-acting mechanism. The 'substrate saturation' hypothesis, whereby increasing amounts of transferred DNA saturates the restriction system (Read et al. 1992, Mol Microbiol 6, 1933-1941) is ruled out by data presented.
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Mair, William. "Dietary restriction in Drosophila melanogaster." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1445680/.
Full textAbstract:
Dietary Restriction (DR), the reduction of nutrient intake without malnutrition, was first shown to extend lifespan in rodents in 1935. DR has subsequently proven to be a 'public' method of increasing longevity since its effects are seen in diverse species, ranging from single-celled organisms through to invertebrates and mammals. The appearance of biomarkers of ageing is delayed by DR in non-human primates and indications are that DR may provide health benefits to humans. DR delays the onset of ageing-related pathologies such as cardiovascular disease and cancer, and increases resistance to environmental stresses in rodents. Evolutionary theories of ageing suggest that the effect of DR on longevity represents a trade-off between reproduction and lifespan. In times of famine, an organism's lifetime reproductive success would be increased if reproductive output and the resulting damage were temporarily reduced. Thus, survival to more plentiful times, when reproduction would once again be the most successful strategy, becomes more likely. In this thesis, I investigate the mechanisms by which DR extends lifespan in the model organism Drosophila melanogaster. I use demographic analysis of the effects of applying DR midway though life to show that DR does not slow the rate of ageing but rather removes an acute, transient risk of death that is reversible. I demonstrate that decreased mortality under DR is not the product of lowered mechanical damage resulting from reduced reproductive output. I also show that, unlike the accepted paradigm in mammals, nutrient composition of the food, not calorie intake, is the key detenninant of lifespan extension via DR in Drosophila. DR flies are shown to be resistant to starvation, which may be indicative of the mechanisms through which DR extends life. However, DR flies are not globally resistant to other environmental stresses including thermal stress, in contrast to DR rodents that have increased thermotolerance. Together, these data give insight into the effects of DR in Drosophila and provide a framework for determining the acute risk of death posed by high nutrient intake. They also provide future directions for work in mammalian systems that will enable us to better understand if the mechanisms by which DR extends life really are conserved across species, or whether they are examples of convergent evolution.
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Miller, Christopher B. "Sleep restriction therapy : experimental studies." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5760/.
Full textAbstract:
Insomnia is a common disturbance of sleep which can be treated effectively with cognitive behavioural therapy; a multicomponent ‘package’ of cognitive and behavioural strategies. Sleep restriction therapy is thought to be one of the most potent behavioural components of cognitive behavioural therapy. Subjective measures of sleep and daytime functioning improve not only with cognitive behavioural therapy, but also during and following sleep restriction therapy. However, it is unknown when these changes occur or if there are associated objective changes. This thesis addresses these issues, and presents: 1. a review of the literature of therapy and original research; 2. evaluates the nature and timing of changes in self-reported daytime functioning during therapy; 3. profiles potential objective changes (in measurements of sleep, plasma and salivary cortisol concentrations & temperature); and 4. compares patients with different subtypes of insomnia and healthy good sleeping controls for possible differences within the brain that might serve as future targets for treatment. The final general discussion ties together the results of these data-based chapters. The following section aims to provide a brief summary of the overall thesis. This Ph.D. was undertaken as Cotutelle Agreement between the Universities of Glasgow, United Kingdom and Sydney, Australia. Specific chapters relate to the data collection performed at these two sites. Consequently this thesis has been split into specific chapters from where the data were obtained. Chapters four and five consist of data acquired from Glasgow, United Kingdom whilst in chapters six and seven the data were acquired in Sydney, Australia.
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Mugodo, James, and n/a. "Plant species rarity and data restriction influence the prediction success of species distribution models." University of Canberra. Resource, Environmental & Heritage Sciences, 2002. http://erl.canberra.edu.au./public/adt-AUC20050530.112801.
Full textAbstract:
There is a growing need for accurate distribution data for both common and rare plant
species for conservation planning and ecological research purposes. A database of more than
500 observations for nine tree species with different ecological and geographical
distributions and a range of frequencies of occurrence in south-eastern New South Wales
(Australia) was used to compare the predictive performance of logistic regression models,
generalised additive models (GAMs) and classification tree models (CTMs) using different
data restriction regimes and several model-building strategies. Environmental variables
(mean annual rainfall, mean summer rainfall, mean winter rainfall, mean annual temperature,
mean maximum summer temperature, mean minimum winter temperature, mean daily
radiation, mean daily summer radiation, mean daily June radiation, lithology and
topography) were used to model the distribution of each of the plant species in the study
area.
Model predictive performance was measured as the area under the curve of a receiver
operating characteristic (ROC) plot. The initial predictive performance of logistic regression
models and generalised additive models (GAMs) using unrestricted, temperature restricted,
major gradient restricted and climatic domain restricted data gave results that were contrary
to current practice in species distribution modelling. Although climatic domain restriction
has been used in other studies, it was found to produce models that had the lowest predictive
performance. The performance of domain restricted models was significantly (p = 0.007)
inferior to the performance of major gradient restricted models when the predictions of the
models were confined to the climatic domain of the species. Furthermore, the effect of data
restriction on model predictive performance was found to depend on the species as shown by
a significant interaction between species and data restriction treatment (p = 0.013). As found
in other studies however, the predictive performance of GAM was significantly (p = 0.003)
better than that of logistic regression. The superiority of GAM over logistic regression was
unaffected by different data restriction regimes and was not significantly different within
species.
The logistic regression models used in the initial performance comparisons were based on
models developed using the forward selection procedure in a rigorous-fitting model-building
framework that was designed to produce parsimonious models. The rigorous-fitting modelbuilding
framework involved testing for the significant reduction in model deviance (p =
0.05) and significance of the parameter estimates (p = 0.05). The size of the parameter
estimates and their standard errors were inspected because large estimates and/or standard
errors are an indication of model degradation from overfilling or effecls such as mullicollinearily.
For additional variables to be included in a model, they had to contribule
significantly (p = 0.025) to the model prediclive performance. An attempt to improve the
performance of species distribution models using logistic regression models in a rigorousfitting
model-building framework, the backward elimination procedure was employed for
model selection, bul it yielded models with reduced performance.
A liberal-filling model-building framework that used significant model deviance reduction at
p = 0.05 (low significance models) and 0.00001 (high significance models) levels as the
major criterion for variable selection was employed for the development of logistic
regression models using the forward selection and backward elimination procedures. Liberal
filling yielded models that had a significantly greater predictive performance than the
rigorous-fitting logistic regression models (p = 0.0006). The predictive performance of the
former models was comparable to that of GAM and classification tree models (CTMs). The
low significance liberal-filling models had a much larger number of variables than the high
significance liberal-fitting models, but with no significant increase in predictive
performance. To develop liberal-filling CTMs, the tree shrinking program in S-PLUS was
used to produce a number of trees of differenl sizes (subtrees) by optimally reducing the size
of a full CTM for a given species. The 10-fold cross-validated model deviance for the
subtrees was plotted against the size of the subtree as a means of selecting an appropriate
tree size. In contrast to liberal-fitting logistic regression, liberal-fitting CTMs had poor predictive performance.
Species geographical range and species prevalence within the study area were used to
categorise the tree species into different distributional forms. These were then used, to
compare the effect of plant species rarity on the predictive performance of logistic regression
models, GAMs and CTMs. The distributional forms included restricted and rare (RR)
species (Eucalyptus paliformis and Eucalyptus kybeanensis), restricted and common (RC)
species (Eucalyptus delegatensis, Eucryphia moorei and Eucalyptus fraxinoides),
widespread and rare (WR) species (Eucalyptus data) and widespread and common (WC)
species (Eucalyptus sieberi, Eucalyptus pauciflora and Eucalyptus fastigata). There were
significant differences (p = 0.076) in predictive performance among the distributional forms
for the logistic regression and GAM. The predictive performance for the WR distributional
form was significantly lower than the performance for the other plant species distributional
forms. The predictive performance for the RC and RR distributional forms was significantly
greater than the performance for the WC distributional form. The trend in model predictive
performance among plant species distributional forms was similar for CTMs except that the
CTMs had poor predictive performance for the RR distributional form.
This study shows the importance of data restriction to model predictive performance with
major gradient data restriction being recommended for consistently high performance. Given
the appropriate model selection strategy, logistic regression, GAM and CTM have similar
predictive performance. Logistic regression requires a high significance liberal-fitting
strategy to both maximise its predictive performance and to select a relatively small model
that could be useful for framing future ecological hypotheses about the distribution of
individual plant species. The results for the modelling of plant species for conservation
purposes were encouraging since logistic regression and GAM performed well for the
restricted and rare species, which are usually of greater conservation concern.
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deVries, Tiffany Dawn. "Neural Activation in Blood-Flow-Restricted Versus Non-Blood-Flow-Restricted Exercise: An fMRI Study." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/5878.
Full textAbstract:
Functional magnetic resonance imaging (fMRI) can be used to track neural activation in the brain during functional activities. The purpose of this study was to investigate brain neural responses to blood flow restricted (BFR) versus control handgrip exercise. Using a randomized crossover design, 25 subjects (12 males, 13 females) completed handgrip exercises during two conditions: BFR vs. control. To familiarize participants with the exercise conditions, one week prior to MRI scanning participants completed each exercise condition once on separate days, with 72 hours between days. The following week fMRI scans were performed at the same time of day, separated by 72 hours. The exercise protocol consisted of five 30-second sets of squeezing a nonmetallic handgrip exerciser (a reported 13.6 kg resistance), doing as many repetitions as possible, with 20-second rest intervals between sets. We saw a significant main effect of exercise condition (BFR versus control) between premotor dorsal (PMd)(F = 5.71, p = 0.022), premotor ventral (PMv)(F = 8.21, p = 0.007), and right ventral striatum (VS_R)(F = 7.36, p = 0.01). When considering anatomical regions of interest, we did not find significant differences between exercise conditions in bilateral S1 (p > 0.82), primary motor cortex (M1)(p > 0.33), supplementary motor area (SMA)(p > 0.66), cerebellum (CB)(p > 0.70), insular cortex (INS)(p > 0.45), anterior cingulate cortex (ACC)(p > 0.24), or thalamus (TH)(p > 0.66). Bilateral ACC (ACC_B), right middle frontal gyrus (MFG_R), and the right primary sensory cortex (S1_R) showed significant linear trends (p = 0.001) over the five exercise sets. Finally, the S1_R, left primary sensory cortex (S1_L), and the right anterior cingulate cortex (ACC_R) showed a main effect of set (p < 0.02). These data demonstrate that acute training with BFR during handgrip exercise results in different neural activation patterns in select areas of the brain, compared to a control. These results show that while completing less work with BFR exercise, subjects can achieve a similar amount of brain neural activation as with a higher-volume exercise. Brain neural activation is important to overall patient health and these findings may be important for prescribing training with BFR in clinical and applied research settings.
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Gomes, Josà Weligton FÃlix. "General equilibrium model for computable policy analysis fiscal agent heterogeneous restricted and non restricted credit." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9873.
Full textAbstract:
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThis research aims to develop a computable general equilibrium model with heterogeneous agents restricted (p-type) and not restricted to credit (q-type) for policy analysis. We used data from the National Accounts (IBGE), PNAD (2009), IPEADATA, to calibrate the model according to the Brazilian economy in 2009. According to the model 11:31% of agents (p-type) generate 0:65% of the total income and are responsible for paying 0:66% of the total tax burden. While other agents (q-type) generate 99:35% of income accounting for 99:34% of the payment of the tax burden. In terms of importance of sources of income, while for p-type income transfers correspond to 55% of labor income for agents of q-type these account for only 16%, which leads to dierent choices of work and leisure between these two types of agents.
O presente trabalho tem como objetivo desenvolver um modelo de equilbrio geral comput avel com agentes heterog^eneos restritos (tipo p) e n~ao restritos ao credito (tipo q) para ns de analise de poltica. Utilizou-se dados das Contas Nacionais (IBGE), PNAD (2009), IPEADATA, para calibrar o modelo segundo a economia brasileira no ano de 2009. De acordo com o modelo, 11; 31% dos agentes (tipo p) geram 0; 65% do total da renda e s~ao responsaveis por pagar 0; 66% da carga total tributaria. Enquanto que os demais agentes (tipo q) geram 99; 35% da renda sendo responsaveis por 99; 34% do pagamento da carga tributaria. Em termos de import^ancia das fontes de rendimentos, enquanto para o tipo p rendas de transfer^encias correspondem a 55% da renda do trabalho, para agentes do tipo q estas correspondem a apenas 16%, o que provoca escolhas distintas de trabalho e lazer entre esses dois tipos de agentes.
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Doronina, Victoria Alexandrovna. "The mechanism of regulation of the restriction activity of the EcoKI, a type I restriction enzyme." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/10881.
Full textAbstract:
The type I restriction enzyme EcoKI is an oligomeric enzyme consisting of subunits responsible for DNA target recognition (HsdS), DNA modification (HsdM) and the ATP-dependent translocation and cleavage of unmodified DNA (HsdR). It was shown in vivo and in vitro that some mutations in hsdM, which impair modification activity of EcoKI, result in a restriction-proficient modification-deficient enzyme. The survival of the mutant bacteria is dependent on the presence of functional ClpXP protease; HsdR is degraded by ClpXP in the restriction-proficient modification-deficient mutant. This degradation requires a restriction complex capable of ATP-dependent translocation and occurs before the completion of the restriction pathway. Degradation of the restriction subunit results in a phenomenon referred to as restriction alleviation (RA). If hsdR is present in high copy number, thereby increasing the level of modification-deficient EcoKI, ClpXP is unable to protect the bacterial chromosome from attack by EcoKI. A restriction-proficient modification-deficient mutant retains some residual restriction activity, which is efficient against DNA that enters the bacterium in the double-stranded form but not against DNA that enters in the single-stranded form. The level of HsdR is depleted in the cytoplasmic but not in the membrane fraction under the conditions that lead to restriction alleviation. However, compartmentalisation of EcoKI cannot explain why chromosomal DNA triggers ClpXP-dependent degradation of HsdR whereas foreign DNA does not. ClpXP protects unmodified chromosomal DNA but not foreign DNA from the resident restriction complex.
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Saïda, Fakhri. "Etude de l'endoribonucléase de restriction RegB." Phd thesis, Ecole Polytechnique X, 2003. http://pastel.archives-ouvertes.fr/pastel-00000707.
Full textAbstract:
L'endoribonucléase de restriction RegB est une enzyme produite par le bactériophage T4. Elle est impliquée dans la transition phase précoce-phase moyenne durant le cycle lytique du virus. RegB coupe avec une spécificité quasi absolue la séquence GGAG impliquée notamment dans l'initiation de la traduction chez la bactérie Escherichia coli. Nous avons caractérisé dans cette thèse de façon précise la toxicité de RegB dans la bactérie et nous avons proposé des outils pour contourner cette toxicité tels la manipulation du nombre de copies du vecteur d'expression ou l'atténuation de l'efficacité du site d'initiation de la traduction. Nous avons, par ailleurs, proposé une application de RegB pour la construction d'un vecteur de clonage à sélection positive et à expression duale dans les systèmes procaryotes et eucaryotes. L'étude par RMN du 31P de la cinétique de clivage d'un ARN par RegB a permis de définir RegB comme une "transphosphorylase libérant un phosphodiester 2', 3'-cyclique". Des études de mutagenèses dirigées et aléatoires combinées à l'évolution du gène regB dans un virus apparenté au phage T4 (le virus RB49) ont mis en évidence le rôle des résidus Glutamate 19, Histidine 48, Arginine 52 et Histidine 68 dans l'activité de RegB. Le mutant RegB H48A a été choisi pour construire un modèle structural du site actif de RegB. L'attribution séquentielle de cette protéine par RMN hétéronucléaire 1H/15N/13C a été entreprise avec succès.
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Zhou, Da Sheng. "Eigenvalues statistics for restricted trace ensembles." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2182958.
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Walls, Barrett Hamilton. "Coloring girth restricted graphs on surfaces." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/28939.
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Lam, Bee K. "Restricted spanning trees and graph partitioning." Curtin University of Technology, School of Mathematics and Statistics, 1999. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=10306.
Full textAbstract:
A network is a system that involves movement or flow of some commodities such as goods and services. In fact any structure that is in the form of a system of components some of which interact can be considered as a network. In network design the problem is often to construct economical and reliable networks which satisfy certain requirements and which are optimal according to some criterion such as cost, output or performance. Graph theory is useful when the requirements of the network can be expressed in terms of graph parameters, usually as bounds. Some of the graph parameters that have been considered include: degree; distance; diameter; and connectivity. Problems with these parameter restrictions are usually from a class of NP-complete problems with instances that require exponential computer time to solve by available algorithms.The major focus of this thesis is to develop fast and efficient heuristics for some of these NP-complete problems. The two main topics analysed are Restricted Spanning Trees and Graph Partitioning. The aim of the Restricted Spanning Trees section is to construct the most efficient spanning tree (connected network) subject to various degree constraints. These degree constraints imposed are usually in the form of an upper bound. The upper bound represents the maximum number of connections allowed on a particular vertex. The Graph Partitioning section considers the problem of clustering vertices of the graph into sets such that the overall cost of the edges in the different sets is minimised.Chapter 1 provides the notation and terminology used throughout the thesis and a review and summary of the thesis.A literature review of related work that has been carried out to date is presented in Chapter 2. Some of the more promising results are discussed. The first part of the chapter surveys work related to the Restricted Spanning Tree problem. ++Analysis of both exact and heuristic methods is given. The second part of Chapter 2 provides a survey of the Graph Partitioning problem. We discuss the many different approaches that have been proposed to solve this problem. The quality of computational results achieved is discussed.Chapter 3 considers the Degree Constraint Minimum Weight Spanning Tree problem. This problem arises in networks where a given terminal is only allowed connections to a maximum number of specified terminals. We consider a number of cases including: same degree constraint on each vertex; different degree constraint on some vertices; and when the degree constraint is only on one or two vertices. A number of heuristics are developed and implemented and compared against an exact Branch and Cut algorithm. Our computational results demonstrated the value of our better performing heuristics.Chapter 4 considers the complexity of the (1,k)-tree problem. This problem is defined m given a graph G with maximum degree k find a spanning tree T with all vertices having degree 1 or k. Analysis is done on graphs with maximum degree 3, 4 and 5. Results establishing that the (1,3)-tree and (1, 4)-tree problems are NP-complete are presented. Further consideration is also given to the complexity of spanning trees with degree from the set { 1, 3, 5}. Analysis is also carried out on the number of degree one vertices in the (1, k)-tree. Presentation of heuristic procedures to solve this NP-complete problem concludes the chapter.Chapter 5 is devoted to the Graph Partitioning problem. A number of heuristics are presented and extensive computational work carried out. Computational findings support the usefulness of the heuristic methods both in terms of quality and time.We conclude this thesis by detailing some future work that can be carried out.
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Johnston, Robert S. "Modeling the effects of restricted randomization." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0003/NQ31993.pdf.
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Hadjifaradji, Saeed. "Learning algorithms for restricted neural networks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0016/NQ48102.pdf.
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Liakhovitch, Evgueni. "Genetic algorithm using restricted sequence alignments." Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1172598174.
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Papadimitropoulos, Christos. "Fourier restriction phenomenon in thin sets." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4625.
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We study the Fourier restriction phenomenon in settings where there is no underlying proper smooth subvariety. We prove an (Lp, L2) restriction theorem in general locally compact abelian groups and apply it in groups such as (Z/pLZ)n, R and locally compact ultrametric fields K. The problem of existence of Salem sets in a locally compact ultrametric field (K, | · |) is also considered. We prove that for every 0 < α < 1 and ǫ > 0 there exist a set E ⊂ K and a measure μ supported on E such that the Hausdorff dimension of E equals α and |bμ(x)| ≤ C|x|−α 2 +ǫ. We also establish the optimal extension of the Hausdorff-Young inequality in the compact ring of integers R of a locally compact ultrametric field K. We shall prove the following: For every 1 ≤ p ≤ 2 there is a Banach function space Fp(R) with σ-order continuous norm such that (i) Lp(R) ( Fp(R) ( L1(R) for every 1 < p < 2. (ii) The Fourier transform F maps Fp(R) to ℓp′ continuously. (iii) Lp(R) is continuously included in Fp(R) and Fp(R) is continuously included in L1(R). (iv) If Z is a Banach function space with the same properties as Fp(R) above, then Z is continuously included in Fp(R). (v) F1(R) = L1(R) and F2(R) = L2(R).
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Chen, Z. "Passive network synthesis of restricted complexity." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597545.
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This dissertation is concerned with passive network synthesis in a mechanical context and applications to vehicle suspensions. This dissertation first presents a modified test for positive-realness of real-rational functions which appears only subtly different from a known condition. The test allows existing results to be derived more simply and allows more general results to be established. We then consider a realisation problem of restricted complexity where the number of dampers and inerters is restricted to one in each case, while allowing an arbitrary number of springs and no transformers (levers). The solution uses element extraction of the damper and inerter followed by the derivation of a necessary and sufficient condition for the one-element-kind (transformerless) realisation of an associated three-port network. This involves the derivation of a necessary and sufficient condition for a third-order non-negative definite matrix to be reducible to a paramount matrix using a diagonal transformation. It is shown that the relevant class of mechanical admittances can be parametrised in terms of five circuit arrangements each containing four springs. We investigate and compare the performances of the five circuit arrangements proposed when applied to suspension systems. One of the five circuits has appeared in the literature and therefore serves as the benchmark. One or more circuit arrangements appear to outperform the benchmark in terms of each individual performance measure among the three of interest and a multi-objective performance measure incorporating two of the three individual performance measures. Finally, we consider the minimum reactance synthesis of a class of biquadratic functions by reactance extraction. We show that at most four dampers are needed to synthesise the remaining resistive 3-port network when explicit conditions are met. The results are an advancement on an equivalent problem studied in the electrical network case.
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Bah, Bubacarr. "Restricted isometry constants in compressed sensing." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7642.
Full textAbstract:
Compressed Sensing (CS) is a framework where we measure data through a non-adaptive linear mapping with far fewer measurements that the ambient dimension of the data. This is made possible by the exploitation of the inherent structure (simplicity) in the data being measured. The central issues in this framework is the design and analysis of the measurement operator (matrix) and recovery algorithms. Restricted isometry constants (RIC) of the measurement matrix are the most widely used tool for the analysis of CS recovery algorithms. The addition of the subscripts 1 and 2 below reflects the two RIC variants developed in the CS literature, they refer to the ℓ1-norm and ℓ2-norm respectively. The RIC2 of a matrix A measures how close to an isometry is the action of A on vectors with few nonzero entries, measured in the ℓ2-norm. This, and related quantities, provide a mechanism by which standard eigen-analysis can be applied to topics relying on sparsity. Specifically, the upper and lower RIC2 of a matrix A of size n × N is the maximum and the minimum deviation from unity (one) of the largest and smallest, respectively, square of singular values of all (N/k)matrices formed by taking k columns from A. Calculation of the RIC2 is intractable for most matrices due to its combinatorial nature; however, many random matrices typically have bounded RIC2 in some range of problem sizes (k, n,N). We provide the best known bound on the RIC2 for Gaussian matrices, which is also the smallest known bound on the RIC2 for any large rectangular matrix. Our results are built on the prior bounds of Blanchard, Cartis, and Tanner in Compressed Sensing: How sharp is the Restricted Isometry Property?, with improvements achieved by grouping submatrices that share a substantial number of columns. RIC2 bounds have been presented for a variety of random matrices, matrix dimensions and sparsity ranges. We provide explicit formulae for RIC2 bounds, of n × N Gaussian matrices with sparsity k, in three settings: a) n/N fixed and k/n approaching zero, b) k/n fixed and n/N approaching zero, and c) n/N approaching zero with k/n decaying inverse logarithmically in N/n; in these three settings the RICs a) decay to zero, b) become unbounded (or approach inherent bounds), and c) approach a non-zero constant. Implications of these results for RIC2 based analysis of CS algorithms are presented. The RIC2 of sparse mean zero random matrices can be bounded by using concentration bounds of Gaussian matrices. However, this RIC2 approach does not capture the benefits of the sparse matrices, and in so doing gives pessimistic bounds. RIC1 is a variant of RIC2 where the nearness to an isometry is measured in the ℓ1-norm, which is both able to better capture the structure of sparse matrices and allows for the analysis of non-mean zero matrices. We consider a probabilistic construction of sparse random matrices where each column has a fixed number of non-zeros whose row indices are drawn uniformly at random. These matrices have a one-to-one correspondence with the adjacency matrices of fixed left degree expander graphs. We present formulae for the expected cardinality of the set of neighbours for these graphs, and present a tail bound on the probability that this cardinality will be less than the expected value. Deducible from this bound is a similar bound for the expansion of the graph which is of interest in many applications. These bounds are derived through a more detailed analysis of collisions in unions of sets using a dyadic splitting technique. This bound allows for quantitative sampling theorems on existence of expander graphs and the sparse random matrices we consider and also quantitative CS sampling theorems when using sparse non mean-zero measurement matrices.