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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
511

Användaranpassning av instruktioner

Karlsson, Catarina January 2008 (has links)
Detta arbete har syftat till att ta reda på vad som är viktigt att tänka på vid utformning av instruktioner för CAD-användare. Som praktikfall har en studie gjorts på Volvo IT där deras instruktioner för CAD/CAM/CAE-systemet CATIA V5 har granskats. Undersökningen mynnade ut i en användarstudie där erfarna användare av systemet fick möjlighet att diskutera den support som finns i dagsläget samt ställa krav på framtida instruktioner. Kraven som togs fram har legat till grund för riktlinjer för hur morgondagens instruktioner skulle kunna göras mer användaranpassade. Några områden som är viktiga att ta hänsyn till är bland annat: att ta tillvara på användarnas erfarenhet, involvera användarna vid framtagandet av instruktionerna, ta reda på hur instruktionenrna läses samt skapa rubrikter som underlättar informationssökning för användarna.
512

Ergo Mopp : Från koncept till produkt / Ergo Mop : From concept to product

Kamf, Tobias January 2010 (has links)
This thesis describes the work process and the results for the development of a newkind of ergonomic cleaning mop, ranging from basic concept to a virtually productionready digital prototype. The project was made in cooperation with, Ömer Altun, whowas also the project supervisor, and whose plan it is to launch this new product onthe market in a foreseeable future. The mop is meant to be used by both professionalcleaning staff and ordinary home users. What makes this product unique is that it hasa movable center piece that simplifies the cleaning under low furniture.The work began with the establishment of a product requirements specification andlater a study of similar products and existing functional models was conducted. Afterthese surveys the work began with refining the existing concepts in order to makethem more complete. In consultation with Ömer, further refining of one of these newconcepts was conducted, but was split into seven smaller steps.After the initial refining process, effort shifted into the investigation and selection ofappropriate materials and manufacturing methods. At this stage, two experimentswere also conducted and subsequently used to support the final decisions concerningthe choice of materials and design.When the materials and methods were adopted, a detailed CAD model of the wholeproduct and related technical drawings was made and also a number of FEM-analyseson all critical details, to ensure that performance requirements were met, wasconducted. These CAD models are closer described in detail in the chapter“Detaljkonstruktion”.In the final sections of discussion and evaluation are suggestions for furtherimprovements. And also some evaluation of the work process and the problems andsolutions encountered during the project execution.
513

Digitalt byggande

Molin, Olof January 2010 (has links)
No description available.
514

Utveckling av modulbaserad 11C-processutrustning inom PET : Presentation av idéer och koncept / Development of module-based 11C process equipment within PET : Presentation of ideas and concepts

Fredén, Emil, Johansson, Sebastian January 2010 (has links)
This report describes the planning and the accomplishment of the final diploma workat the study program Mechanical Engineering, Department of Engineering Sciences, Uppsala University. Two students carried out the diploma work at GE HealthcareHusbyborg in Uppsala. The aim of the diploma work was to develop and improve existing processequipment for 11C-radiochemistry in PET. The process equipment was to be dividedinto smaller independent modules to make it more flexible. Part of the existingprocess equipment is an oven that is supposed to perform a specific chemicalreaction. One of the main goals was to study and improve this oven. The work could be divided into three main phases: 1.Present concepts for one module, and interface between different modules. 2. Analyze and choose components for the module mentioned above. 3. Present concepts for the oven, which is placed in the module mentioned above. At the beginning, user requirements were listed in cooperation with the mentor. Later, components available on the market and the existing process equipment wereanalyzed. A product function analysis of the oven was made to show its function and design. The concept phase was mainly about brainstorming to generate ideas. Later, hybridization was used as a method to combine different ideas. Then two prototypeswere built and tested. The test results showed which idea seemed to be the best.Different concepts were assessed and put into a concept selection matrix, after which the best was chosen and developed further.
515

Implementering av BIM i ett projektledningsföretag inom byggindustrin : Implementation of BIM in a project management company within construction industry

Magyari, Mark, Ebire, Oyebanji, Lot, Jonas January 2011 (has links)
Syftet med rapporten är att skapa en förståelse om vad BIM är och undersöka vad BIM för med sig i projekteringen. Det som kommer behandlas är BIM-samordnarens uppgifter, de olika negativa aspekter som påträffats vid användandet av BIM samt en presentation av olika program så kallade verktyg som används vid BIM-projektering. / Our main aim of this report is to create a foundation for understanding the meaning of BIM and explore the major contributions of BIM to construction design. One of the topics that we will be laying emphases on is the role and duties of a BIM-coordinator and different negative aspects that could be encountered when using BIM. So also presentation of different programmes (tools) used in the process of BIM-design.
516

Koncept för koppling av boj till generator i ett vågkraftverk

Mahbob, Feroz January 2012 (has links)
Den största delen av all energi på jorden utvinns idag från fossila bränslen. Detta innebär stora faror för miljön såsom utsläpp av växthusgaser. För att uppnå en hållbar utveckling behöver vi miljövänliga och förnybara energikällor. Vågkraft är därför en bra lösning för framtidens energiförsörjning med många fördelar. På avdelning för Elektricitetslära i Ångströmslaboratoriet vid Uppsala universitet jobbar man med utvecklingen av ett vågkraftkoncept där en boj som flyter på havsytan kopplas till en generator på havets botten. Arbetet sker inom det så kallade Lysekilsprojektet och systemet testas på en anläggning i Lysekil på västkusten. I den befintliga konstruktionen kopplas bojen med hjälp av tre kättingar till en vajer som går till generatorn. På grund av vågornas rörelse uppstår nötningar där de tre kättingarna kopplas till bojen och till varandra. Det finns också stor risk för korrosion. Syftet med detta examensarbete är att komma på ett nytt koncept för infästningen mellan bojen och vajern till generatorn. Målet är att minska nötningen och på så sätt minska behovet av underhållsarbete. Det första steget i arbetet var att generera flera koncept på möjliga konstruktionslösningar. Ett koncept som baseras på att fyra balkar placeras ovanpå bojen med en platta i mitten där vajern fästes med hjälp av en fästanordning valdes som det lämpligaste konceptet. Konceptet vidareutvecklades med hjälp av CAD-programmet SolidWorks. Konstruktionen som arbetades fram motsvarar till största delen den kraftspecifikation som arbetades fram i början av projektet. Den kan klara av en kraft på 500 kN, som kan uppstå vid de största vågorna. Den har inga rörliga delar, så det kommer inte att ske någon nötning. Istället för kättingar används en vajer som är väl skyddad mot korrosion. Konstruktionen behöver inte lika mycket underhåll som den befintliga konstruktionen med kättingar. Den är också lätt att montera, förutsatt att rätt verktyg konstrueras. / Today most of all energy on earth is produced from fossil fuels. This presents a danger to the environment such asemission of greenhouse gases. In order to achieve sustainable development we need clean and renewable energy sources. Wavepower is a good solution for future energy supply, with many advantages. The Department of Electricity in the Ångström Laboratory at Uppsala University works with the development of a wave power concept where a buoy floating on the sea surface is connected to a generator on the sea floor. The work is performed within the so-called Lysekilproject and the system is tested at a facility in Lysekil on the Swedish west coast. In the existing design, a buoy is connected to the wire that goes from the generator by means of three chains. Due to wave movement wear occurs where the three chains are coupled to the buoy and to each other. There is also a risk of corrosion. The purpose of this thesis is to come up with a new concept of attachment between the buoy and wire to the generator. The objective is to reduce wear, thus reducing the need for maintenance work. The first stage of this work was to generate several concepts of possible design solutions. A concept which is based on four beams placed on top of the buoy and a plate in the middle where the wire is secured by a fastener was selected as the preferred concept. This concept was further developed using the CAD-program SolidWorks. The final structure corresponds to a large extent to the requirement specification which was developed in the beginning of the project. It can withstand a force of 500 kN, which may arise due to the biggest wave during a storm. It has no moving parts, so there will be no wear. Instead of chains a wire is used, which is well protected against corrosion. The proposed design does not need as much maintenance as the existing structure with chains. It is also easy to assemble, provided that the right tool is constructed.
517

COMPUTATION OF THE ARC LENGTH FROM THE SHADOW BOUNDARY OF A CAD OBJECT

Amoateng, Eric January 2012 (has links)
CAD objects are geometrical descriptions of physical scenes from the real world. Ray tracing is used to project the objects onto a pixel screen. A lit and a shadow zone are formed according to the direction of the incoming field (light) and the orientation of the pixel screen. The arc length along the surface of the object, from the shadow boundary to a point in the lit zone, is computed by means of numerical integration. The arclengths corresponding to two orthogonal directions that are aligned with the pixels on the pixel screen are computed and used for interpolation to obtain the arc length for all directions. A number of simulations for various CAD geometries are made using a ray-tracer implemented in FORTRAN 90.
518

Landscape Grammar

Mayall, Kevin January 2002 (has links)
The protection and enhancement of visual resources constitute an on-going challenge to the planning authorities in many communities. The crux of this challenge is to guide development towards built and natural landscape forms that will not cause detriment to an existing landscape character. To understand and cope with this problem, there is the need for a means to define and model a landscape's character, to identify methods for constructing that character definition, to create tools for storing and using such a definition to visualize its spatial manifestations, and to incorporate alternative development regulatory parameters in order to assess their impact on landscape character. Current spatial data technologies are able to portray inventories of specific, real-world objects. While well established in the planning profession, these technologies and their attendant data manipulation tools do not easily facilitate the creation of generalized, non-specific statements that are applicable across a region. Such generalized statements regarding visual and spatial features are at the heart of descriptions of landscape character and implicit within most planning regulations intended to produce a desirable landscape character. Current spatial data tools therefore do not satisfy the stated needs of planning for landscape character. In satisfying these conceptual, methodological and technological deficiencies, the research presented in this dissertation defines and demonstrates a theory of landscape grammar which formally draws parallels between the structures of linguistics and the character of landscapes. A landscape grammar defines a landscape character using a spatial vocabulary and syntax rules and can be applied to a site to generate landscape forms that embody the defined character. In this dissertation, the spatial counterparts of the linguistic concepts of vocabulary and grammar rules are formalized and implemented for use in a custom-developed geographic information system. Methods that enable the use of landscape grammars in a planning environment are presented and subsequently applied through the formal expression of planning regulations into the grammar-based model. The theory, methods and software implementation are demonstrated using a residential area of the island of Bermuda. The iterative grammatical generation of an example two-dimensional landscape scene is demonstrated with further three-dimensional representations of the results for visualization purposes. Alternative planning regulations are also incorporated into the case study grammar and resultant three-dimensional landscapes are shown. Several suggestions for future research on landscape grammars are offered in the conclusions of the dissertation.
519

On the Use of Directed Moves for Placement in VLSI CAD

Vorwerk, Kristofer January 2009 (has links)
Search-based placement methods have long been used for placing integrated circuits targeting the field programmable gate array (FPGA) and standard cell design styles. Such methods offer the potential for high-quality solutions but often come at the cost of long run-times compared to alternative methods. This dissertation examines strategies for enhancing local search heuristics---and in particular, simulated annealing---through the application of directed moves. These moves help to guide a search-based optimizer by focusing efforts on states which are most likely to yield productive improvement, effectively pruning the size of the search space. The engineering theory and implementation details of directed moves are discussed in the context of both field programmable gate array and standard cell designs. This work explores the ways in which such moves can be used to improve the quality of FPGA placements, improve the robustness of floorplan repair and legalization methods for mixed-size standard cell designs, and enhance the quality of detailed placement for standard cell circuits. The analysis presented herein confirms the validity and efficacy of directed moves, and supports the use of such heuristics within various optimization frameworks.
520

The Role of single minded 2 short in mammary gland development and breast cancer

Kwak, Hyeong-il 15 May 2009 (has links)
Single minded 2 (Sim2) is a member of the basic helix-loop-helix Per-ARNT-Sim (Period-Arylhydrocarbon Nuclear Translocator-Single minded) family. Human SIM2 is involved in the etiology of the Down’s phenotype. In addition to the physical and mental deficiencies associated with DS, it has become apparent that women with DS are 10-25 times less likely to develop breast cancer in comparison to age-matched normal populations. Such significant effects on breast cancer susceptibility are thought to result from gene dosage effects of one or more tumor suppressor genes on chromosome 21. Here we report the identification and transcriptional characterization of mouse Sim2s, a splice variant of Sim2, which is missing the carboxyl Pro/Ala-rich repressive domain. Similar to full-length Sim2, Sim2s interacts with ARNT and to a lesser extent, ARNT2. The effects of Sim2s on transcriptional regulation through hypoxia-, dioxin- and central midline response elements are different than that of full length Sim2. Specifically, Sim2s exerts a less repressive effect on hypoxia-induced gene expression than full length Sim2, but is just as effective as Sim2 at repressing TCDD-induced gene expression from a dioxin response element. Interestingly, Sim2s binds to and activates expression from a central midline response element-controlled reporter through an ARNT transactivation domain-dependent mechanism. Forced expression of SIM2s in MDA-MB-435 breast cancer cells significantly inhibited proliferation, reduced anchorage-independent growth, and decreased invasive potential. SIM2s directly decreased expression of matrix metalloprotease-3, a known mediator of breast cancer metastasis. In addition, loss of Sim2 in the mouse mammary gland increased ductal branching, accelerated lobuloalveolar-like precocious hyperplasia, and decreased cell apoptosis, suggesting that SIM2s is a mammary tumor suppressor. Sim2-/- mammary glands lose E-cadherin expression, suggesting that Sim2s plays a role in regulating E-cadherin/beta-catenin signaling. Loss of Sim2 in the mammary glands also resulted in dramatically increased MMP3 expression. The mechanism of SIM2smediated repression of MMP3 was found to be due to its ability to inhibit AP-1 binding to the MMP3 promoter. These results suggest that SIM2s contributes to the breast cancer protective effects observed in DS individuals.

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