996 resultados para Design things


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This research has been focused at the development of a tuned systematic design methodology, which gives the best performance in a computer aided environment and utilises a cross-technological approach, specially tested with and for laser processed microwave mechanics. A tuned design process scheme is also presented. Because of the currently large production volumes of microwave and radio frequency mechanics even slight improvements of design methodologies or manufacturing technologies would give reasonable possibilities for cost reduction. The typical number of required iteration cycles could be reduced to one fifth of normal. The research area dealing with the methodologies is divided firstly into a function-oriented, a performance-oriented or a manufacturability-oriented product design. Alternatively various approaches can be developed for a customer-oriented, a quality-oriented, a cost-oriented or an organisation-oriented design. However, the real need for improvements is between these two extremes. This means that the effective methodology for the designers should not be too limited (like in the performance-oriented design) or too general (like in the organisation-oriented design), but it should, include the context of the design environment. This is the area where the current research is focused. To test the developed tuned design methodology for laser processing (TDMLP) and the tuned optimising algorithm for laser processing (TOLP), seven different industrial product applications for microwave mechanics have been designed, CAD-modelled and manufactured by using laser in small production series. To verify that the performance of these products meets the required level and to ensure the objectiveness ofthe results extensive laboratory tests were used for all designed prototypes. As an example a Ku-band horn antenna can be laser processed from steel in 2 minutes at the same time obtaining a comparable electrical performance of classical aluminium units or the residual resistance of a laser joint in steel could be limited to 72 milliohmia.

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This project proposes a preliminary architectural design for a control and data processing center, also known as 'ground segment', for Earth observation satellites.

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Background: Understanding the relationship between gene expression changes, enzyme activity shifts, and the corresponding physiological adaptive response of organisms to environmental cues is crucial in explaining how cells cope with stress. For example, adaptation of yeast to heat shock involves a characteristic profile of changes to the expression levels of genes coding for enzymes of the glycolytic pathway and some of its branches. The experimental determination of changes in gene expression profiles provides a descriptive picture of the adaptive response to stress. However, it does not explain why a particular profile is selected for any given response. Results: We used mathematical models and analysis of in silico gene expression profiles (GEPs) to understand how changes in gene expression correlate to an efficient response of yeast cells to heat shock. An exhaustive set of GEPs, matched with the corresponding set of enzyme activities, was simulated and analyzed. The effectiveness of each profile in the response to heat shock was evaluated according to relevant physiological and functional criteria. The small subset of GEPs that lead to effective physiological responses after heat shock was identified as the result of the tuning of several evolutionary criteria. The experimentally observed transcriptional changes in response to heat shock belong to this set and can be explained by quantitative design principles at the physiological level that ultimately constrain changes in gene expression. Conclusion: Our theoretical approach suggests a method for understanding the combined effect of changes in the expression of multiple genes on the activity of metabolic pathways, and consequently on the adaptation of cellular metabolism to heat shock. This method identifies quantitative design principles that facilitate understating the response of the cell to stress.

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documented accurately since 1960. Most records are based on nest findings and there have been few direct observations or captures, mainly because live trapping of this species is not simple. Therefore, an efficient trapping technique is needed for population studies and to facilitate the management of its habitat. By combining the methods used to capture very small (Suncus etruscus) and climbing (Muscardinus avellanarius) mammals, we developed a design using Longworth traps with mouse excluders set on suspended platforms. This allowed us to trap more harvest mice in four field sessions of 60 trap-nights than have ever been caught previously since its discovery in Switzerland.

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The introduction of affordable, consumer-oriented 3-D printers is a milestone in the current "maker movement," which has been heralded as the next industrial revolution. Combined with free and open sharing of detailed design blueprints and accessible development tools, rapid prototypes of complex products can now be assembled in one's own garage--a game-changer reminiscent of the early days of personal computing. At the same time, 3-D printing has also allowed the scientific and engineering community to build the "little things" that help a lab get up and running much faster and easier than ever before.

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The need for high performance, high precision, and energy saving in rotating machinery demands an alternative solution to traditional bearings. Because of the contactless operation principle, the rotating machines employing active magnetic bearings (AMBs) provide many advantages over the traditional ones. The advantages such as contamination-free operation, low maintenance costs, high rotational speeds, low parasitic losses, programmable stiffness and damping, and vibration insulation come at expense of high cost, and complex technical solution. All these properties make the use of AMBs appropriate primarily for specific and highly demanding applications. High performance and high precision control requires model-based control methods and accurate models of the flexible rotor. In turn, complex models lead to high-order controllers and feature considerable computational burden. Fortunately, in the last few years the advancements in signal processing devices provide new perspective on the real-time control of AMBs. The design and the real-time digital implementation of the high-order LQ controllers, which focus on fast execution times, are the subjects of this work. In particular, the control design and implementation in the field programmable gate array (FPGA) circuits are investigated. The optimal design is guided by the physical constraints of the system for selecting the optimal weighting matrices. The plant model is complemented by augmenting appropriate disturbance models. The compensation of the force-field nonlinearities is proposed for decreasing the uncertainty of the actuator. A disturbance-observer-based unbalance compensation for canceling the magnetic force vibrations or vibrations in the measured positions is presented. The theoretical studies are verified by the practical experiments utilizing a custom-built laboratory test rig. The test rig uses a prototyping control platform developed in the scope of this work. To sum up, the work makes a step in the direction of an embedded single-chip FPGA-based controller of AMBs.

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This paper aims to better understand the development of students’ learning processes when participating actively in a specific Computer Supported Collaborative Learning system called KnowCat. To this end, a longitudinal case study was designed, in which eighteen university students took part in a 12-month (two semesters) learning project. During this time period, the students followed an instructional process, using some elements of KnowCat (KnowCat key features) design to support and improve their interaction processes, especially peer learning processes. Our research involved both supervising the students’ collaborative learning processes throughout the learning project and focusing our analysis on the qualitative evolution of the students’ interaction processes and on the development of metacognitive learning processes. The results of the current research reveal that the instructional application of the CSCL-KnowCat system may favour and improve the development of the students’ metacognitive learning processes. Additionally, the implications of the design of computer supported collaborative learning networks and pedagogical issues are discussed in this paper.

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La protection des données est un élément essentiel d'un Etat de droit et une société démocratique, car elle accorde à chaque individu le droit de disposer de ce qui fait partie de sa sphère privée. Actuellement en Suisse, la loi fédérale sur la protection des données (LPD) est en vigueur depuis 1993. En 2010, l'Office fédéral de la justice a supervisé une évaluation de son efficacité : il en résulte que cette dernière a été prouvée, mais tendra à diminuer fortement dans les années à suivre. Pour causes principales : l'évolution des technologies, caractérisée notamment par le développement des moyens de traitement de données toujours plus variés et conséquents, et un manque d'informations des individus par rapport à la protection des données en générale et à leurs droits. Suite à l'évaluation, cinq objectifs de révision ont été formulés par le Conseil fédéral, dont celui d'intégrer la privacy by design ou « protection de la vie privée dès la conception » dans la loi. Ce concept, qui est également repris dans les travaux européens en cours, est développé à l'origine par l'Information and Privacy Commissionner de l'Ontario (Canada), Ann Cavoukian. Le principe général de la privacy by design est que la protection de la vie privée doit être incluse dans les systèmes traitant les données lors de leur conception. Souvent évoquée comme une solution idéale, répondant au problème de l'inadéquation de la loi par la logique de prévention qu'elle promeut, la privacy by design demeure toutefois un souhait dont l'application n'est que peu analysée. Ce travail cherche justement à répondre à la question de la manière de la mettre en oeuvre dans la législation suisse. Se basant sur les textes et la doctrine juridiques et une littérature dans les domaines de l'économie, l'informatique, la politique et la sociologie des données personnelles, il propose tout d'abord une revue générale des principes et définitions des concepts-clés de la protection des données en Suisse et dans le cadre international. Puis, il propose deux possibilités d'intégration de la privacy by design : la première est une solution privée non contraignante qui consiste à promouvoir le concept et faire en sorte que les responsables de traitement décident par eux-mêmes d'intégrer la privacy by design dans leurs projets ; ce procédé est possible grâce au renforcement du processus de certification déjà en cours. La deuxième option est une solution contraignante visant à intégrer le principe directement dans la loi et de prendre les mesures pour le rendre effectif ; ce travail montre que le développement de la figure du conseiller à la protection des données permet d'atteindre cet objectif. Enfin, des considérations générales sur l'application du principe sont abordées, telles que l'influence des développements en cours dans l'Union européenne sur la Suisse par rapport à la protection des données et la limite posée par le principe de territorialité.

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We present a case study of the redesign of the organizational presentation and content of the Virtual Library website at the Universitat Oberta de Catalunya (Open University of Catalonia, UOC), based on a user-centered design strategy. The aim of the redesign was to provide users with more intuitive, usable and understandable content (textual content, resources and services) by implementing criteria of customization, transparency and proximity. The study also presents a selection of best practices for applying these criteria to the design of other library websites.

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Self-nanoemulsifying drug delivery systems of gemfibrozil were developed under Quality by Design approach for improvement of dissolution and oral absorption. Preliminary screening was performed to select proper components combination. BoxBehnken experimental design was employed as statistical tool to optimize the formulation variables, X1 (Cremophor® EL), X2 (Capmul® MCM-C8), and X3 (lemon essential oil). Systems were assessed for visual characteristics (emulsification efficacy), turbidity, droplet size, polydispersity index and drug release. Different pH media were also assayed for optimization. Following optimization, the values of formulation components (X1, X2, and X3) were 32.43%, 29.73% and 21.62%, respectively (16.22% of gemfibrozil). Transmission electron microscopy demonstrated spherical droplet morphology. SNEEDS release study was compared to commercial tablets. Optimized SNEDDS formulation of gemfibrozil showed a significant increase in dissolution rate compared to conventional tablets. Both formulations followed Weibull mathematical model release with a significant difference in td parameter in favor of the SNEDDS. Equally amodelistic parameters were calculated being the dissolution efficiency significantly higher for SNEDDS, confirming that the developed SNEDDS formulation was superior to commercial formulation with respect to in vitro dissolution profile. This paper provides an overview of the SNEDDS of the gemfibrozil as a promising alternative to improve oral absorption.

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Tätä diplomityötä sponsoroi suuri Isobritannialainen lentokoneteollisuudessa toimiva yritys, joka huomasi että globaalin tuotantostrategian ollessa painopisteenä ja tietoteknisten järjestelmien kuten CAD/CAM ollessa merkittävänä osana tuotantoa, on löydettävä ymmärrys siitä, mitkä ovat tuotannon tietojärjestelmien tarpeet ja onko niiden kehittämisestä hyötyä yritykselle.Diplomityössä selitetään Internet teknologiaan perustuvan kioskin kehittämisestä tietotukijärjestelmäksi tuotanto-osastolle, jossa valmistetaan moottorin osia CNC-koneilla. Kioskeissa on piirteitä, jotka voisivat osoittautua hyödyllisiksi myös tuotantoympäristöissä ja siksi tässä työssä tutkitaan kioskiin perustuvaa lähestymistapaa tuotantoympäristöön sovellettuna.Diplomityö kuvaa informaatiokioskin kehittämistä alkaen alkuvaatimusten keruusta tietojärjestelmää varten, tietojärjestelmän suunnittelu- ja kehitysvaiheen sekä lopuksi analysoi kioskin onnistuneisuutta tuotantoympäristössä käytettävyystutkimuksen avulla, joka suoritettiin sen jälkeen kun kioski oli implementoitu tehtaassa.Johtopäätökset osoittavat, että kioski on hyvin implementoitavissa tuotantoympäristöön ja todistaa, että tuotantoinformaation jakelu sähköisessä muodossa on huomattavasti tehokkaampaa kuin paperilla. Käyttäjien kommentit osoittavat että kioski on sopiva heidän tietotarpeisiinsa ja siitä on hyötyä heidän työlleen. Kioski tarjoaa hyötyjä tuotantotason lisäksi myös johtotasolle.

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Turbokoneet ja etenkin höyryturbiinit ovat usein suunniteltu ja optimoitu toimimaan tietyssä toimintapisteessä jossa häviöt on minimoitu ja hyötysuhde maksimoitu. Joissakin tapauksissa on kuitenkin tarpeellista käyttää turbiinia toimintapisteen ulkopuolella. Tällöin turbiinin läpi virtaava massavirta muuttuu ja yleensä heikentää hyötysuhdetta. Turbokoneiden suorituskykyä voidaan parantaa käyttämällä kolmidimensionaalisesti muotoiltuja siipiä. Työssä on vertailtu laskennallisesti kahta kohtuullisesti muotoiltua suutinta (Compound lean ja Controlled flow) niiden suunnitellun toimintapisteen ulkopuolella. Kolmas suutin, ilman kolmidimensionaalista muotoilua on mukana vertailukohteena. Suutinten suorituskykyä tutkitaan laskennallisen virtausmekaniikan avulla olosuhteissa, jotka ovat toimintapisteen ulkopuolella. Virtauksen muutoksia tutkitaan kokonaispainehäviön, isentrooppisen hyötysuhteen ja virtauspinnan yhdenmukaisuuden avulla. Virtauspintoja verrataan ulosvirtauskulman, massavirran ja toisiovirtausvektoreiden jakauman avulla. Erot suutinten suorituskykyvyssä korostavat ylikuormalla. Kun massavirran arvoa on kohotettu eniten, Compound lean suuttimilla hyötysuhde laskee Controlled flow suuttimeen verrattuna vähemmän. Alikuormalla, kun massavirran arvoa lasketaan, erot suuttimien suorituskyvyssä pienenevät ja tutkittujen suuttimien ulosvirtaus on samankaltainen.

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Key management has a fundamental role in secure communications. Designing and testing of key management protocols is tricky. These protocols must work flawlessly despite of any abuse. The main objective of this work was to design and implement a tool that helps to specify the protocol and makes it possible to test the protocol while it is still under development. This tool generates compile-ready java code from a key management protocol model. A modelling method for these protocols, which uses Unified Modeling Language (UML) was also developed. The protocol is modelled, exported as an XMI and read by the code generator tool. The code generator generates java code that is immediately executable with a test software after compilation.

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Tässä diplomityössä perehdytään WAP:in Push -viitekehykseen. WAP-standardit määrittelevät kuinka Internet-tyyppisiä palveluita, joita voidaan käyttää erilaisia mobiileja päätelaiteitteita käyttäen, toteutetaan tehokkaalla ja verkkoteknologiasta riippumattomalla tavalla. WAP pohjautuu Internet:iin, mutta huomioi pienten päätelaitteiden ja mobiiliverkkojen rajoitukset ja erikoisominaisuudet. WAP Push viitekehys määrittelee verkon aloittaman palvelusisällön toimittamisen. Työn teoriaosassa käydään läpi yleinen WAP-arkkitehtuuri ja WAP-protokollapino käyttäen vertailukohtina lanka-Internetin arkkitehtuuria ja protokollapinoa. Edellistä perustana käyttäen tutustaan WAP Push -viitekehykseen. Käytännönosassa kuvataan WAP Push -välityspalvelimen suunnittelu ja kehitystyö. WAP Push -välityspalvelin on keskeinen verkkoelementti WAP Push -viitekehyksessä. WAP Push -välityspalvelin yhdistää Internetin ja mobiiliverkon tavalla, joka piilottaa teknologiaeroavaisuudet Internetissä olevalta palveluntuottajalta.