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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.
1

Em busca de um algoritmo construtivo para autômatos celulares reversíveis: a abordagem das regras primitivas e derivadas

Kronemberger, Guilherme 28 January 2008 (has links)
Made available in DSpace on 2016-03-15T19:38:08Z (GMT). No. of bitstreams: 1 Guilherme Kronemberger.pdf: 1225637 bytes, checksum: 6f698faf7a8661b382c4977e4b07f631 (MD5) Previous issue date: 2008-01-28 / Cellular automata have been studied as computer models in many different areas. They have many properties, one of them being reversibility. Reversible cellular automata can be used, among other applications, for data compressing and encryption. Apparently, the reversible rules featured in the literature seem to have been derived through exhaustive searches in their corresponding spaces. However, it would be important the availability of an algorithm that would allow their direct and easy construction, different from what occurs in literature. This is the aim of this work. Along this line, we tried to come up with an algorithm to allow the identification of one-dimensional, reversible cellular automaton rules. This was based on reversible rules with 2 states and 2, 3, 4 and 5 cells per neighborhood, and on those with 3 states and 2 and 3 cells per neighborhood, all of them drawn out of exhaustive analysis and from the literature. By studying these rules it was possible to verify in each space that: all reversible rules are balanced; they are symmetrically distributed; a subset of them herein denoted primitive reversible rules, RPs have a simple formation law, defined by homogeneous blocks of states; and, if a rule is reversible, so are all its dynamically equivalent rules. In the attempt to obtain the targetted algorithm, an approach was explored in which the non-primitive reversible rules (the so-called derived rules, RDs) were supposed to be obtained from the primitives. Along this line, two ways to construct the RDs were tried out, one based upon using all RPs jointly as a group, and another, using them individually; however, neither of them led to a positive result. Additionally, relations between the properties of reversibility and conservativity of a rule have also been studied in the rule spaces considered. / Autômatos celulares têm sido estudados como modelos computacionais em diversas áreas, sendo que muitas são as suas propriedades, entre elas a reversibilidade. Autômatos celulares reversíveis podem ser usados, entre outras aplicações, para compactação ou encriptação de dados. Aparentemente, as regras reversíveis apresentadas na literatura parecem ter sido derivadas apenas através de buscas exaustivas em seus espaços correspondentes. No entanto, seria importante a existência de um algoritmo que permitisse construí-las fácil e diretamente, diferente do que acontece na literatura. Este é o objetivo deste trabalho. Neste sentido, buscou-se um algoritmo que permitesse identificar regras de autômatos celulares unidimensionais reversíveis. Para tanto, foram obtidas em análises exaustivas e na literatura todas as regras reversíveis de 2 estados e vizinhanças de 2, 3, 4 e 5 células, e de 3 estados e vizinhanças de 2 e 3 células. Com o estudo destas regras constatou-se em cada espaço que: todas as regras reversíveis são balanceadas; elas se distribuem simetricamente; um subconjunto delas aqui denominadas regras reversíveis primitivas, RPs possui lei de formação simples, definida por blocos homogêneos de estados; e, se uma regra é reversível, todas as suas equivalentes dinâmicas também o são. Na tentativa de se obter o algoritmo desejado explorou-se uma abordagem em que as regras reversíveis não primitivas (denominadas regras derivadas, RDs), seriam obtidas a partir das primitivas. Nesse sentido foram testados dois esquemas de construção das RDs, um baseado na utilização conjunta de todas as RPs, e outro, utilizando-as individualmente; entretanto, ambos não levaram a resultado positivo. Adicionalmente, estudou-se a relação entre as propriedades de reversibilidade e conservatividade de regras nos espaços considerados.
2

Etude du rôle des fibroblastes associés au mélanome dans la modulation de la réponse immune anti-tumorale : influence de la sécrétion de métalloprotéinases matricielles sur la lyse tumorale dépendante des cellules NK et de l’hypoxie sur leur potentiel immunosuppresseur / Role of melanoma-associated fibroblasts in the modulation of anti-tumor immune response : influence of matrix metalloproteinases secretion on NK cell-dependent tumor lysis and hypoxia on their immunosuppressive potential

Ziani, Linda 02 June 2017 (has links)
Les fibroblastes associés au cancer (CAF) jouent un rôle central dans un processus complexe d'interaction entre les tumeurs et le stroma et favorisent la croissance tumorale. Des preuves émergentes suggèrent que ces fibroblastes sont impliqués dans l'altération de la réponse immune anti-tumorale. Cependant, les mécanismes immuno-modulateurs sous-jacents dépendants de ces fibroblastes ne sont encore que très partiellement définis. Au cours de ma thèse, j’ai mis en évidence que les fibroblastes associés au mélanome diminuent la susceptibilité des cellules tumorales de mélanome à la lyse induite par les cellules Natural killer (NK) par un mécanisme dépendant de la sécrétion de métalloprotéinases matricielles (MMPs) actives. Cette sécrétion de MMPs réduit l'expression de deux ligands du récepteur activateur NKG2D, MICA/B, à la surface des cellules tumorales et diminue par conséquent l'activité cytotoxique des cellules NK dépendante de NKG2D contre les cellules tumorales de mélanome. D’autre part, grâce à une approche génomique globale, mon travail a montré que l’hypoxie au sein du stroma tumoral pourrait augmenter les capacités immuno-modulatrices des CAFs en modifiant l’expression d’un ensemble de gènes qui codent pour des protéines immunosuppressives. L’ensemble de ces résultats démontrent donc que les CAFs sont des déterminants essentiels modifiant la susceptibilité des cellules tumorales aux cellules tueuses mais qu’il existerait également un dialogue entre le microenvironnement hypoxique et les CAFs leur permettant d’augmenter leur potentiel immunosuppresseur. / Cancer-associated fibroblasts (CAF) play a central role in a complex process of interaction between tumors and stroma and promote tumor growth. Emerging evidence suggest that these fibroblasts are involved in the alteration of the anti-tumor immune response. However, the underlying immunomodulatory mechanisms dependent on these fibroblasts are still only partially defined. During my thesis, I demonstrated that melanoma-associated fibroblasts decrease the susceptibility of melanoma tumor cells to Natural killer (NK) cell lysis through a mechanism dependent on the secretion of active matrix metalloproteinases (MMPs). This secretion of MMPs reduces the expression of the two NKG2D ligands, MICA/B at the surface of the tumor cells and consequently decreases the NKG2D-dependent cytotoxic activity of NK cells against melanoma tumor cells. On the other hand, using a global genomic approach, my results suggested that hypoxia within the tumor stroma could increase the immunomodulatory capacities of CAFs by modifying the expression of a set of genes that encode for immunosuppressive proteins. Together, our results show that CAFs are essential determinants modifying the susceptibility of tumor cells to killer cells but that there is also a crosstalk between the hypoxic microenvironment and the CAFs allowing them to increase their immunosuppressive potential.
3

Tidplanering av ett stort byggprojekt : En kvalitativ intervjubaserad studie av Nya Karolinska Solna / Time planning for a large scale project : A qualitative interview based study on New Karolinska Solna

Lignerkrona, Karin, Malki, Michael January 2013 (has links)
Detta examensarbete, Tidplanering av ett stort byggprojekt är en fördjupning inom byggstyrning med fokus på hur planeringsarbetet kan förbättras. Rapporten baseras på Skanskas planeringsarbete av Nya Karolinska Solna. Fördjupningen bygger på kvalitativa intervjuer med personal ur utvalda projektfaser och erforderliga dokument, som ger en närmare inblick i hur arbetet med tidplanering utförs och kommuniceras. Arbetet resulterade i slutsatsen att ledningsverktyget Last planner får samtliga befattningar på byggarbetsplatsen att kommunicera bättre med varandra och uppmärksammar eventuella problem i god tid. Skanska rekommenderas därför att implementera Last planner i framtida projekt. Skanska bör avsätta mer tid för projektering innan produktionen påbörjar. Detta gör att de minskar risken för förseningar i sina projekt. Tillämpning av 4D‐odeller förenklar förståelsen för hur projektet utvecklas under arbetets gång i jämförelse med det planerade arbetet. Därför kan Skanska med fördel använda sig utav 4D-modellering inom framtida projekt. Skanska rekommenderas att ta fram arbetsmallar för 4D-modelleringen och till stöd för framställandet av 3-veckorstidplaner, där det framgår hur de använder vissa funktioner i planeringsprogrammen samt riktlinjer för hur tidplaner ska utformas. Vi rekommenderar att planerare ges möjligheten att hålla återkommande möten för erfarenhetsutbyte. Även om faserna skiljer sig åt, kan planerare använda sig av varandras erfarenheter i framtida projekt och det är ett bra sätt att bibehålla kunskapen inom Skanska. / This thesis is an in-depth study of building management focusing solely on time planning of a large-scale building project. The report is based on planning within New Karolinska Solna, a project by Skanska. The study was conducted through qualitative interviews on site as well as acquiring necessary documents in relation to the thesis subject. The material that was gathered gave insight into how the time plans are produced  and communicated. This brought about the conclusion that Last planner, a communications method, should be implemented in future Skanska projects as it is a holistic approach to communicating time plans by involving all involved in the project.  The design team should be given more time to finish all necessary drawings before construction work begins. This will result in a decrease of delays caused by lack of drawings. Applying the use of 4D-models clarifies, in a generally understandable way, the development of the construction work in comparison to what was initially planned. Therefor, the usage of such models is an advantage for use in future projects. Develop working templates for 4D-models, and as support for producing 3-week look-ahead time plans, with  clear guidelines for the layout of time plans as well as how certain functions are used within planning programs. We recommend that the planners be given the opportunity to hold regular meetings to exchange ideas and individual experience, even though phases may differ from each other. This would be a positive step in maintaining knowledge within Skanska.
4

Algumas propriedades de autômatos celulares unidimensionais conservativos e reversíveis

Oliveira, Angelo Schranko de 28 January 2009 (has links)
Made available in DSpace on 2016-04-18T21:39:48Z (GMT). No. of bitstreams: 2 Angelo Schranko de Oliveira1.pdf: 925871 bytes, checksum: 812a592f67dbda8b36f5168fbd5f2598 (MD5) Angelo Schranko de Oliveira2.pdf: 2918106 bytes, checksum: 0969a0bf28b426ce84fe4595d80a73c2 (MD5) Previous issue date: 2009-01-28 / Wolfram Research, Inc. / Cellular automata (CAs) can be defined as discrete dynamical systems over n-dimensional networks of locally connected components, whose evolution occur in a discrete, synchronous and homogeneous fashion. Among their several applications, they have been used as a tool for complex systems modeling governed by fundamental laws of conservation (number-conserving cellular automata) or reversibility (reversible cellular automata). Another fundamental property that can be observed in CAs is regarding to their linearity (linear cellular automata) or nonlinearity. Usually, linear phenomena present low dynamic complexity, however, nonlinear phenoma can present complex behaviours like sensitive dependence on initial conditions and routes to chaos. This work focuses on investigating properties of cellular automata belonging to the intersection of those four classes, namely, reversible, number-conserving, and linear or nonlinear cellular automata. After presenting basic definitions, the notions of number-conserving cellular automata, conservation degree and reversibility are reviewed. Following, a dynamical characterisation parameter which relates the reversibility property of a onedimensional cellular automaton and the pre-images of their basic blocks is introduced, and some proofs of its general properties are given. Empirical observations herein suggest that a cellular automaton is reversible and number-conserving if, and only if, its local transition function is a composition of the local transition functions of the reversible, number-conserving cellular automata with neighbourhood size n=2; such an observation was drawn for neighbourhood sizes n∈{2, 3, 4, 5, 6} and number of states q=2; n∈{2, 3} and q=3; n∈{2, 3} and q=4. A proof for such a conjecture would allow the enumeration between neighbourhood lengths and the quantity of reversible, numberconserving cellular automata in the corresponding space, which can be easily identified by working out the compositions of the local transition functions with n=2. Finally, some relationships between reversible, number-conserving, linear and nonlinear CA rules, their spatio-temporal diagrams and basin of attraction fields are presented. / Autômatos celulares (ACs) podem ser definidos como sistemas dinâmicos sobre redes ndimensionais de componentes localmente conectados, cuja evolução ocorre de forma discreta, síncrona e homogênea. Dentre suas diversas aplicações, têm sido utilizados como ferramenta para modelagem de sistemas complexos regidos por leis fundamentais de conservação (autômatos celulares conservativos) ou reversibilidade (autômatos celulares reversíveis). Outra propriedade fundamental que pode ser observada nos ACs diz respeito à sua linearidade (autômatos celulares lineares) ou nãolinearidade. Fenômenos lineares normalmente apresentam menor complexidade dinâmica, enquanto fenômenos não-lineares podem apresentar propriedades tais como sensibilidade às condições iniciais e rotas para caos. O presente trabalho concentra-se na investigação de propriedades de autômatos celulares unidimensionais pertencentes à interseção dessas quatro classes, isto é, autômatos celulares unidimensionais conservativos, reversíveis, e lineares ou não-lineares. Após definições básicas, são revisitados os conceitos de conservabilidade e reversibilidade. Em seguida, introduz-se um parâmetro de caracterização dinâmica que relaciona a distribuição do número de pré-imagens dos blocos básicos à reversibilidade de autômatos celulares unidimensionais e apresentam-se algumas demonstrações decsuas propriedades gerais. Observações empíricas aqui realizadas sugerem que um autômato celular unidimensional é conservativo e reversível se, e somente se, sua função local de transição de estados é uma composição das funções locais de transição de estado dos autômatos celulares conservativos e reversíveis de vizinhança de comprimento n=2; tal observação foi constatada para vizinhanças de comprimento n∈{2, 3, 4, 5, 6} e quantidade de estados q=2; n∈{2, 3} e q=3; n∈{2, 3} e q=4. Uma demonstração para tal conjectura permitiria estabelecer uma enumeração entre os comprimentos das vizinhanças e a quantidade de autômatos celulares unidimensionais conservativos e reversíveis no espaço correspondente, os quais podem ser facilmente identificados através do cálculo das composições das funções locais de transição de estados com n=2. Por fim, apresentam-se relações entre as classes dos ACs conservativos, reversíveis, lineares e não-lineares, suas dinâmicas espaçotemporais e campos de bacias de atração.
5

The New Infusion Pump System at New Karolinska Solna / Nya Karolinska och det nya Infusionspumpssystemet

Lindemalm, Josefin, Akkawi, Anna January 2017 (has links)
In November 2016 a brand new and highly technological hospital called New Karolinska Solna opened in Stockholm. In connection with the planning of the hospital, new medical devices were procured, including a new infusion system that is now in use. Previously, each ward at the hospital had their own pumps and was responsible for updates and maintenance. Now, the hospital will instead have a floating pump system, which means that the hospital will own the pumps. The infusion pumps will be floating between the wards without being linked to a specific ward or department. The updates that were previously done when the need arose at the ward will now be a common process for the entire hospital. The aim of the project was to develop new guidelines for how the update process should be done on New Karolinska Solna's new infusion pump system. Through interviews with key personnel during the procurement process, the medical technicians department and caseworkers, new guidelines have been written, given the already existing technical conditions. During the course of the project it has been found that there are major shortcomings of information and communication within the hospital. The guidelines presented in the result are an important part to ensure that information related to the update comes to the caregivers at New Karolinska Solna, thus simplifying and streamlining the update of the infusion pumps.
6

Energikostnader vid uttorkning av byggfukt i betongbjälklag : En beräkningsnyckel för uttorkningsplaner / Energy costs in drying construction water in concrete floors : A calculation key for drying out plans

Fernström, Karin, Granath, Viktoria January 2014 (has links)
Fukthantering är idag, trots god kunskap inom ämnet, ett stort problem inom byggproduktion då tunga betongstommar ska torkas ut under pressade tidsplaner. Det finns en uppsjö av beräkningsmetoder och hjälpmedel, exempelvis ByggaF och Torka S. Däremot finns inget enkelt sätt att kombinera uttorkning, energiåtgång och kostnader som är användbart i produktionen. Miljön är kanske ett av det här århundradets största samhällsproblem. Lokala brister kan få globala konsekvenser och för att bygga ett hållbart samhälle måste detaljnivån studeras. Byggbranschen är en stor energibrukare där stor vikt på energibesparingar läggs i förvaltningsskedet, medan det försummas i produktionsskedet. Överkonsumtion av energi är kostsamt, vilket olyckligtvis betyder mer för många än dess miljöpåverkan. Genom att ta fram en metod som förenklar och påvisar möjligheterna till kostnadsbesparingar kan både miljövinster och ekonomin gynnas, såväl för företag som samhälle. Med Skanskas högt satta miljömål, bland annat gällande energianvändningen är det därför intressant att jämföra energin som åtgår för ett driftår under produktionen med ett driftår under förvaltningsskedet. Efter att ha tagit del av intern dokumentation gällande fuktdimensionering, mätningar och egna mätningar med värmekamera samt Testo-loggar har tolkningar av data resulterat i beräkningar av effekt- och energiförluster. Resultatet visar energiåtgången och kostnadsskillnader per kvadratmeter, vilket ligger till grund för bestämningen av parametrar till en beräkningsnyckel i Excel-format. Beräkningsnyckeln är en förenklad metod där hänsyn tas till dels projektspecifika parametrar och dels generella parametrar som berör fuktmekanik. Förhoppningen är att den ska vara tydlig och användarvänlig för att kunna appliceras i kommande projekt. / Moisture in building construction is today, despite adequate competence, a large problem within the building process, when massive concrete constructions need to be dried out of construction water during a short time. There are numerous calculation methods and tools, e.g. ByggaF and TorkaS. However at this time, there is no simple way to be used during the manufacturing process that combines the process of drying out water, its use of energy and costs. The environmental issue is perhaps one of the largest problems the society has yet to tackle during this century. Local shortcomings could have global effects, and in order to build a sustainable community, the key is in the details. The construction business is a huge consumer of energy, where large significance is put on energy savings after the production during maintenance, and sadly neglected during the production process. Excessive consumption of energy is costly, which unfortunately has more importance to some than its impact on the environment. By producing a method that simplifies and demonstrates the opportunities for cost-savings, environmental- and financial benefits can be proven, locally for the company, as well as globally. Skanska’s own high environmental goals, the use of energy among other things, are reason alone for the interest of comparing the amount of energy used during a year of production to a year of maintenance. After reviewing internal documentation regarding the handling of construction water and measured data as well as conducting complementary measurements with a thermo camera and Testo logger, the interpretations of data has resulted in calculations regarding power and energy requirements. The result shows the amount of used energy and cost differences per square meter and is the basis of determining parameters for a calculation key, programmed in Microsoft Office Excel. The key is a simplified method where consideration is taken to project specific parameters as well as general parameters regarding moisture mechanics. The expectation for the key is clarity and usability for easy application in future projects.

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