906 resultados para engineering design process


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Reverse transcriptase (RT) is a multifunctional enzyme in the human immunodeficiency virus (HIV)-1 life cycle and represents a primary target for drug discovery efforts against HIV-1 infection. Two classes of RT inhibitors, the nucleoside RT inhibitors (NRTIs) and the nonnucleoside transcriptase inhibitors are prominently used in the highly active antiretroviral therapy in combination with other anti-HIV drugs. However, the rapid emergence of drug-resistant viral strains has limited the successful rate of the anti-HIV agents. Computational methods are a significant part of the drug design process and indispensable to study drug resistance. In this review, recent advances in computer-aided drug design for the rational design of new compounds against HIV-1 RT using methods such as molecular docking, molecular dynamics, free energy calculations, quantitative structure-activity relationships, pharmacophore modelling and absorption, distribution, metabolism, excretion and toxicity prediction are discussed. Successful applications of these methodologies are also highlighted.

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This paper presents a case study that explores the advantages that can be derived from the use of a design support system during the design of wastewater treatment plants (WWTP). With this objective in mind a simplified but plausible WWTP design case study has been generated with KBDS, a computer-based support system that maintains a historical record of the design process. The study shows how, by employing such a historical record, it is possible to: (1) rank different design proposals responding to a design problem; (2) study the influence of changing the weight of the arguments used in the selection of the most adequate proposal; (3) take advantage of keywords to assist the designer in the search of specific items within the historical records; (4) evaluate automatically thecompliance of alternative design proposals with respect to the design objectives; (5) verify the validity of previous decisions after the modification of the current constraints or specifications; (6) re-use the design records when upgrading an existing WWTP or when designing similar facilities; (7) generate documentation of the decision making process; and (8) associate a variety of documents as annotations to any component in the design history. The paper also shows one possible future role of design support systems as they outgrow their current reactive role as repositories of historical information and start to proactively support the generation of new knowledge during the design process

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This manual captures the experience of practitioners in the Iowa Department of Transportation’s (Iowa DOT’s) Office of Location and Environment (OLE). It also documents the need for coordinated project development efforts during the highway project planning, or location study phase and engineering design. The location study phase establishes: * The definition of, and need for, the highway improvement project * The range of alternatives and many key attributes of the project’s design * The recommended alternative, its impacts, and the agreed-to conditions for project approval The location study process involves developing engineering alternatives, collecting engineering and environmental data, and completing design refinements to accomplish functional designs. The items above also embody the basic content required for projects compliant with the National Environmental Policy Act (NEPA) of 19691, which directs federal agencies to use a systematic, interdisciplinary approach during the planning process whenever proposed actions (or “projects”) have the potential for environmental impacts. In doing so, NEPA requires coordination with stakeholders, review, comment, and public disclosure. Are location studies and environmental studies more about the process or the documents? If properly conducted, they concern both—unbiased and reasonable processes with quality and timely documents. In essence, every project is a story that needs to be told. Engineering and environmental regulations and guidance, as documented in this manual, will help project staff and managers become better storytellers.

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The I-74 Aesthetic Design Guideline (ADG) document has two primary goals: To establish and identify an overall design theme To prioritize enhancement opportunities within the framework of corridor elements The recommendations of this report have been developed based on an “unconstrained” framework for future corridor–wide enhancements. Future funding availability, along with the recommendations of this report, will guide the final design process. ADG Future Uses: This document is intended to be used as a reference to future processes in the following ways: Guidance for I-74 final design teams Reference document for future local community redevelopment initiatives Inspiration for identification and development of other I-74 corridor aesthetic enhancement opportunities Process: As illustrated in Figure 1.3, the overall process for corridor aesthetics began traditionally with inventory and identification of potential aesthetic applications. The ADG does not document all the reports and presentations related to these early design stages, but has incorporated these efforts into the design theme, guiding principles and prioritized enhancements shown on the following pages of this report. The I-74 final design phase will incorporate these recommendations into the project. The consultant design team and representatives of the DOTs have worked with the CAAT members to facilitate community input and have helped develop recommendations for improving I-74 corridor aesthetics. CAAT recommendations have been advanced to the I-74 Advisory Committee for review and endorsement. Both DOTs have reviewed the CAAT recommendations and have endorsed the contents of this report. Figure 1.4 illustrates the status of corridor aesthetic design development. As of the date of this report, aesthetic design is approximately 50% complete. Future detailed design, cost evaluation, feasibility and prioritizations all need to occur for this process to be successfully completed.

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This project developed an automatic conversion software tool that takes input a from an Iowa Department of Transportation (DOT) MicroStation three-dimensional (3D) design file and converts it into a form that can be used by the University of Iowa’s National Advanced Driving Simulator (NADS) MiniSim. Once imported into the simulator, the new roadway has the identical geometric design features as in the Iowa DOT design file. The base roadway appears as a wireframe in the simulator software. Through additional software tools, textures and shading can be applied to the roadway surface and surrounding terrain to produce the visual appearance of an actual road. This tool enables Iowa DOT engineers to work with the universities to create drivable versions of prospective roadway designs. By driving the designs in the simulator, problems can be identified early in the design process. The simulated drives can also be used for public outreach and human factors driving research.

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Abstract In this thesis we present the design of a systematic integrated computer-based approach for detecting potential disruptions from an industry perspective. Following the design science paradigm, we iteratively develop several multi-actor multi-criteria artifacts dedicated to environment scanning. The contributions of this thesis are both theoretical and practical. We demonstrate the successful use of multi-criteria decision-making methods for technology foresight. Furthermore, we illustrate the design of our artifacts using build and-evaluate loops supported with a field study of the Swiss mobile payment industry. To increase the relevance of this study, we systematically interview key Swiss experts for each design iteration. As a result, our research provides a realistic picture of the current situation in the Swiss mobile payment market and reveals previously undiscovered weak signals for future trends. Finally, we suggest a generic design process for environment scanning.

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The Mechanistic-Empirical Pavement Design Guide (MEPDG) was developed under National Cooperative Highway Research Program (NCHRP) Project 1-37A as a novel mechanistic-empirical procedure for the analysis and design of pavements. The MEPDG was subsequently supported by AASHTO’s DARWin-ME and most recently marketed as AASHTOWare Pavement ME Design software as of February 2013. Although the core design process and computational engine have remained the same over the years, some enhancements to the pavement performance prediction models have been implemented along with other documented changes as the MEPDG transitioned to AASHTOWare Pavement ME Design software. Preliminary studies were carried out to determine possible differences between AASHTOWare Pavement ME Design, MEPDG (version 1.1), and DARWin-ME (version 1.1) performance predictions for new jointed plain concrete pavement (JPCP), new hot mix asphalt (HMA), and HMA over JPCP systems. Differences were indeed observed between the pavement performance predictions produced by these different software versions. Further investigation was needed to verify these differences and to evaluate whether identified local calibration factors from the latest MEPDG (version 1.1) were acceptable for use with the latest version (version 2.1.24) of AASHTOWare Pavement ME Design at the time this research was conducted. Therefore, the primary objective of this research was to examine AASHTOWare Pavement ME Design performance predictions using previously identified MEPDG calibration factors (through InTrans Project 11-401) and, if needed, refine the local calibration coefficients of AASHTOWare Pavement ME Design pavement performance predictions for Iowa pavement systems using linear and nonlinear optimization procedures. A total of 130 representative sections across Iowa consisting of JPCP, new HMA, and HMA over JPCP sections were used. The local calibration results of AASHTOWare Pavement ME Design are presented and compared with national and locally calibrated MEPDG models.

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Työn tavoitteena on tutkia intranetin ylläpitoprosessien merkitystä sisäisen viestinnän, tiedonhallinnan ja käytettävyyden kannalta. Työn kirjallisuusosuuden tavoitteena on tutustua yrityksen sisäisen viestinnän eri tekijöihin, tavoitteisiin, merkityksiin ja menetelmiin. Intranetin roolia organisaation kontekstissa tarkastellaan näkökulmista: organisaatio, tieto organisaatiossa, organisaatioiden sisäinen viestintä ja viestintäteknologian keinot sisäiseen viestintään. Kirjallisuusosan toisena tavoitteena on tutustua käyttäjäkeskeisen suunnittelun lähtökohtiin ja malleihin. Nykypäivän tuotteissa käyttäjäkeskeisyys on itsestään selvää, ja se otetaankin huomioon jo tuotesuunnittelun alkuvaiheista lähtien. Työssä tutustutaan kolmeen käyttäjäkeskeisen suunnittelun prosessimalliin: ISO 13407 –prosessimalli, Usability engineering lifecycle ja vaatimusmäärittelyn spiraalimalli. Työssä esitellään myös käyttäjäkeskeisen vaatimusmäärittelyn toteuttamiseen liittyviä vaiheita, tekijöitä ja toimenpiteitä. Työn käytännönosuudessa tarkastellaan case-yrityksen intranet-palvelun nykytilannetta ja kuvataan nykyinen ylläpitoprosessi ja sen ongelmakohdat. Työn tavoitteena on pohtia ratkaisuja näihin ongelmiin. Käytännössä tämä tarkoittaa intranetin vaatimusmäärittelyn tekemistä, jonka pohjalta voidaan tunnistaa kehityskohteet ja tehdä suunnitelma toimintojen kehittämisestä. Työn lopputuloksena saadaan prosessien kuvaus, joilla ylläpito hoituu parhaiten.

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Tämä opinnäytetyö on tehty SkinnAir Oy:lle, ja se käsittelee pientalojen LVI-teknistä suunnittelua pienen suunnitteluyrityksen näkökulmasta. Nykyinen kiivas rakentamistyyli, kasvaneet asumisviihtyvyydenvaatimukset, asennusammattilaisten puute sekä jatkuvasti kohoavat vaatimukset rakennusten energiatehokkuuden parantamiseksi vaativat yhä parempia ja laadukkaampia suunnitelmia pientalojen LVI-teknisten ratkaisujen toteuttamiseksi. Suunnittelusta saatavan heikon tuottavuuden johdosta monet suunnittelutoimistot eivät ole kiinnostuneita pientalojen LVI-suunnittelusta. Tässä työssä pyritään etsimään niitä menetelmiä, joilla erityisesti pieni suunnitteluyritys kykenee parantamaankannattavuuttaan ja nostamaan palvelun laatua kyseisellä suunnittelun osa-alueella. Työ on toteutettu perehtymällä yksityiskohtaisesti suunnitteluprosessin eri vaiheisiin sekä analysoimalla näistä vaiheista saadut tulokset Työssä tunnistetaan erilaiset asiakastyypit sekä heidän tarpeensa. Asiakastarpeiden perusteellasaadaan määritettyä oikeat lähtötiedot kohteen LVI-suunnittelua varten. Työn keskeinen osa on suunnitteluprosessin etenemisen sekä suunnittelutyöhön kuuluvien tehtävien tarkastelu. Tämän tarkastelun avulla pyritään löytämään keinot, joillakyetään tehostamaan suunnitteluprosessin eri vaiheisiin liittyviä toimintoja, parantamaan palvelun laatua sekä lisäksi minimoimaan suunnitteluprosessin aikaisia kustannuksia yrityksen kannattavuuden parantamiseksi. LVI-suunnittelutyön eteneminen painottuu asiakas- ja lähtötietojen keräämiseen sekä eri välivaiheiden hyväksyttämiseen tilaajalla. Suunnittelutyöhön vaikuttavat tekijät saadaan selville jatkuvassa, ennalta hyvin aikataulutetussa asiakaskontaktissa. Asiakkaan huomioiminen suunnitteluprosessin eri vaiheissa parantaa kokonaisvaltaista asiakaspalvelua. Näin asiakkaan saama vastine rahoilleen kasvaa. Suunnittelijan kannalta turhat muutostyöt vähenevät, koska asiakas on selvillä suunnittelutyön etenemisestä. Johtopäätöksenä voidaan todeta, että hyvän suunnitteluprosessin edellytyksenä on yksityiskohtaisten lähdetietojen käyttö. Työn tuloksena ilmeni, että valmiiden, ennalta hyvin laadittujen lomakkeiden käyttäminen parantaa selkeästi suunnittelutyön tehokkuutta. Lopputuloksena syntyi jatkokehittelyä vaativa lomakepohja asiakastarpeisiin perustuvalle lähtötietolomakkeelle. Lisäksi yrityksen käyttöön on tarkoitus laatia tarvittavat tietokannat sekä valmiit asennuspiirrokset. Lopullinen tavoite on rakentaa tässä työssä kuvatuista menetelmistä kattava tietotekninen järjestelmä parantamaan sekä yrityksen kannattavuutta että suunnittelutyön laatua. Lisäksi voidaan todeta, että rakennettava järjestelmä mahdollistaa myös vaativan suunnittelutyön tuotteistamisen.

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Tämä diplomityö tehtiin Convergens Oy:lle. Convergens on elektroniikan suunnittelutoimisto, joka on erikoistunut sulautettuihin järjestelmiin sekä tietoliikennetekniikkaan. Diplomityön tavoitteena oli suunnitella tietokonekortti tietoliikennesovelluksia varten asiakkaalle, jolta vaatimusmäärittelyt tulivat. Työ on rajattu koskemaan laitteen prototyypin suunnittelua. Työssä suunnitellaan pääasiassa WLAN-tukiaseman tietokone. Tukiasema onasennettavissa toimistoihin, varastoihin, kauppoihin sekä myös liikkuvaan ajoneuvoon. Suunnittelussa on otettu nämä asiat huomioon, ja laitteen akun pystyy lataamaan muun muassa auton akulla. Langattomat tekniikat ovat voimakkaasti yleistymässä, ja tämän työn tukiasema tarjoaakin varteenotettavan vaihtoehdon lukuisilla ominaisuuksillaan. Mukana on mm. GPS, Bluetooth sekä Ethernet-valmius. Langattomien tekniikoiden lisäksi myös sulautetut järjestelmät ovat voimakkaasti yleistymässä, ja nykyään mikroprosessoreita löytääkin lähesmistä vain. Tässä projektissa käytetty prosessori on nopeutensa puolesta kilpailukykyinen, ja siitä löytyy useita eri rajapintoja. Jatkossa tietokonekortille on myös tulossa WiMAX-tuki, joka lisää tukiaseman tulevaisuuden arvoa asiakkaalle. Projektiin valittu Freescalen MPC8321E-prosessori on PowerPC-arkkitehtuuriin perustuva ja juuri markkinoille ilmestynyt. Tämä toi mukanaan lisähaasteen, sillä kyseisestä prosessorista ei ollut vielä kaikkea tietoa saatavilla. Mekaniikka toi omat haasteensa mukanaan, sillä se rajoitti piirilevyn koonniin, että ylimääräistä piirilevytilaa ei juurikaan jäänyt. Tämän takia esimerkiksi DDR-muistit olivat haastavia reitittää, sillä muistivetojen on oltava melko samanpituisia keskenään. Käyttöjärjestelmänä projektissa käytetään Linuxia. Suunnittelu alkoi keväällä 2007 ja toimiva prototyyppi oli valmis alkusyksystä. Prototyypin testaus osoitti, että tietokonekortti kykenee täyttämään kaikki asiakkaan vaatimukset. Prototyypin testauksessa löytyneet viat ja optimoinnit on tarkoitus korjata tuotantomalliin, joten se antaa hyvän pohjan jatkosuunnittelua varten.

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This paper analyzes the possibilities of integrating cost information and engineering design. Special emphasis is on finding the potential of using the activity-based costing (ABC) method when formulating cost information for the needs of design engineers. This paper suggests that ABC is more useful than the traditional job order costing, but the negative issue is the fact that ABC models become easily too complicated, i.e. expensive to build and maintain, and difficult to use. For engineering design the most suitable elements of ABC are recognizing activities of the company, constructing acitivity chains, identifying resources, activity and cost drivers, as wellas calculating accurate product costs. ABC systems including numerous cost drivers can become complex. Therefore, a comprehensive ABC based cost information system for the use of design engineers should be considered criticaly. Combining the suitable ideas of ABC with engineering oriented thinking could give competentresults.

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Theultimate goal of any research in the mechanism/kinematic/design area may be called predictive design, ie the optimisation of mechanism proportions in the design stage without requiring extensive life and wear testing. This is an ambitious goal and can be realised through development and refinement of numerical (computational) technology in order to facilitate the design analysis and optimisation of complex mechanisms, mechanical components and systems. As a part of the systematic design methodology this thesis concentrates on kinematic synthesis (kinematic design and analysis) methods in the mechanism synthesis process. The main task of kinematic design is to find all possible solutions in the form of structural parameters to accomplish the desired requirements of motion. Main formulations of kinematic design can be broadly divided to exact synthesis and approximate synthesis formulations. The exact synthesis formulation is based in solving n linear or nonlinear equations in n variables and the solutions for the problem areget by adopting closed form classical or modern algebraic solution methods or using numerical solution methods based on the polynomial continuation or homotopy. The approximate synthesis formulations is based on minimising the approximation error by direct optimisation The main drawbacks of exact synthesis formulationare: (ia) limitations of number of design specifications and (iia) failure in handling design constraints- especially inequality constraints. The main drawbacks of approximate synthesis formulations are: (ib) it is difficult to choose a proper initial linkage and (iib) it is hard to find more than one solution. Recentformulations in solving the approximate synthesis problem adopts polynomial continuation providing several solutions, but it can not handle inequality const-raints. Based on the practical design needs the mixed exact-approximate position synthesis with two exact and an unlimited number of approximate positions has also been developed. The solutions space is presented as a ground pivot map but thepole between the exact positions cannot be selected as a ground pivot. In this thesis the exact synthesis problem of planar mechanism is solved by generating all possible solutions for the optimisation process ¿ including solutions in positive dimensional solution sets - within inequality constraints of structural parameters. Through the literature research it is first shown that the algebraic and numerical solution methods ¿ used in the research area of computational kinematics ¿ are capable of solving non-parametric algebraic systems of n equations inn variables and cannot handle the singularities associated with positive-dimensional solution sets. In this thesis the problem of positive-dimensional solutionsets is solved adopting the main principles from mathematical research area of algebraic geometry in solving parametric ( in the mathematical sense that all parameter values are considered ¿ including the degenerate cases ¿ for which the system is solvable ) algebraic systems of n equations and at least n+1 variables.Adopting the developed solution method in solving the dyadic equations in direct polynomial form in two- to three-precision-points it has been algebraically proved and numerically demonstrated that the map of the ground pivots is ambiguousand that the singularities associated with positive-dimensional solution sets can be solved. The positive-dimensional solution sets associated with the poles might contain physically meaningful solutions in the form of optimal defectfree mechanisms. Traditionally the mechanism optimisation of hydraulically driven boommechanisms is done at early state of the design process. This will result in optimal component design rather than optimal system level design. Modern mechanismoptimisation at system level demands integration of kinematic design methods with mechanical system simulation techniques. In this thesis a new kinematic design method for hydraulically driven boom mechanism is developed and integrated in mechanical system simulation techniques. The developed kinematic design method is based on the combinations of two-precision-point formulation and on optimisation ( with mathematical programming techniques or adopting optimisation methods based on probability and statistics ) of substructures using calculated criteria from the system level response of multidegree-of-freedom mechanisms. Eg. by adopting the mixed exact-approximate position synthesis in direct optimisation (using mathematical programming techniques) with two exact positions and an unlimitednumber of approximate positions the drawbacks of (ia)-(iib) has been cancelled.The design principles of the developed method are based on the design-tree -approach of the mechanical systems and the design method ¿ in principle ¿ is capable of capturing the interrelationship between kinematic and dynamic synthesis simultaneously when the developed kinematic design method is integrated with the mechanical system simulation techniques.

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Over 70% of the total costs of an end product are consequences of decisions that are made during the design process. A search for optimal cross-sections will often have only a marginal effect on the amount of material used if the geometry of a structure is fixed and if the cross-sectional characteristics of its elements are property designed by conventional methods. In recent years, optimalgeometry has become a central area of research in the automated design of structures. It is generally accepted that no single optimisation algorithm is suitable for all engineering design problems. An appropriate algorithm, therefore, mustbe selected individually for each optimisation situation. Modelling is the mosttime consuming phase in the optimisation of steel and metal structures. In thisresearch, the goal was to develop a method and computer program, which reduces the modelling and optimisation time for structural design. The program needed anoptimisation algorithm that is suitable for various engineering design problems. Because Finite Element modelling is commonly used in the design of steel and metal structures, the interaction between a finite element tool and optimisation tool needed a practical solution. The developed method and computer programs were tested with standard optimisation tests and practical design optimisation cases. Three generations of computer programs are developed. The programs combine anoptimisation problem modelling tool and FE-modelling program using three alternate methdos. The modelling and optimisation was demonstrated in the design of a new boom construction and steel structures of flat and ridge roofs. This thesis demonstrates that the most time consuming modelling time is significantly reduced. Modelling errors are reduced and the results are more reliable. A new selection rule for the evolution algorithm, which eliminates the need for constraint weight factors is tested with optimisation cases of the steel structures that include hundreds of constraints. It is seen that the tested algorithm can be used nearly as a black box without parameter settings and penalty factors of the constraints.

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Requirements-relatedissues have been found the third most important risk factor in software projects and as the biggest reason for software project failures. This is not a surprise since; requirements engineering (RE) practices have been reported deficient inmore than 75% of all; enterprises. A problem analysis on small and low maturitysoftware organizations revealed two; central reasons for not starting process improvement efforts: lack of resources and uncertainty; about process improvementeffort paybacks.; In the constructive part of the study a basic RE method, BaRE, was developed to provide an; easy to adopt way to introduce basic systematic RE practices in small and low maturity; organizations. Based on diffusion of innovations literature, thirteen desirable characteristics; were identified for the solution and the method was implemented in five key components:; requirements document template, requirements development practices, requirements; management practices, tool support for requirements management, and training.; The empirical evaluation of the BaRE method was conducted in three industrial case studies. In; this evaluation, two companies established a completely new RE infrastructure following the; suggested practices while the third company conducted continued requirements document; template development based on the provided template and used it extensively in practice. The; real benefits of the adoption of the method were visible in the companies in four to six months; from the start of the evaluation project, and the two small companies in the project completed; their improvement efforts with an input equal to about one person month. The collected dataon; the case studies indicates that the companies implemented new practices with little adaptations; and little effort. Thus it can be concluded that the constructed BaRE method is indeed easy to; adopt and it can help introduce basic systematic RE practices in small organizations.

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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.