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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.
421

Genetic determination and layout rules of visual cortical architecture

Liedtke, Joscha 14 August 2017 (has links)
No description available.
422

Healing of cranial critical sized defects with grafts, stem cells, growth factors and bio-materials

Lappalainen, O.-P. (Olli-Pekka) 01 November 2016 (has links)
Abstract Bone is a highly vascularized tissue which enables a close interaction between blood vessels and osteoid complexes, including osteoblasts and osteoclasts. Iatrogenic bone loss, caused by a surgical intervention or trauma, disrupts circulation in the bone and leads to hypoxia and even necrosis of the adjacent bone. The mechanisms of the bone tissue healing process by regeneration are highly specific. The most common and predictable way to manage a large-sized skull bone defect has traditionally been using the patient’s own bone tissue graft. The problem with the method is damage and pain of the donor site caused by the operation and healing problems. In paediatric patients, there is a limited availability of adequate autologous bone grafts. For this reason, efforts have been made to develop substitute materials in order to avoid the need for large bone grafts. Autologous stem cells have proven to be promising targets for the development of bone substitutes for cranio-maxillofacial bone defects. The main objective of this study was to examine, by using an experimental animal model, differences in the healing of critical-sized calvarial bone defects, similar to cranioplasty, induced with different types of autogenous bone grafts and with adipose tissue- or bone marrow-derived stem cells grown in two commonly used biomaterials, tricalcium phosphate and bioglass. We also investigated the effect of tissue adhesive, fibrin glue, on the healing process of bone defects. The effect of the stimulating growth factor proteins BMP-2, BMP-7 and VEGF on tissue transplants and ossification was also studied. The results of this study support the previously reported findings of accelerated bone graft resorption associated with autologous bone graft use. In particular, the use of fibrin tissue glue in combination with autologous particulated bone grafts reduced the formation of new bone in calvarial lesions. During the initial healing of calvarial bone defects, tricalcium phosphate granules proved to be more effective than solid bioactive glass scaffolds. Furthermore, in combination with adipose-derived stem cells, tricalcium phosphate showed better bone regeneration than the same cells in combination with a bioactive glass scaffold. Combining bone marrow-derived stem cells with biomaterial did not increase bone formation in calvarial critical-sized defects. In this study, there was no evidence of the positive effect of growth factors on cranial bone healing. / Tiivistelmä Luu on runsaasti verisuonitettua kudosta, ja se mahdollistaa tiiviin vuorovaikutuksen verisuonten ja luun rakenteen perusyksikön, osteonin, sekä toiminnallisten solujen osteoblastien ja osteoklastien välillä. Kirurgisen toimenpiteen tai trauman aiheuttama luun vaurio häiritsee luun verenkiertoa ja johtaa hapenpuutteeseen ja jopa nekroosiin vaurioituneessa luun osassa. Luukudoksen paranemisen ja uudistumisen mekanismit ovat pitkälle erilaistuneita ja ne tunnetaan erittäin hyvin. Yleisin ja ennusteeltaan luotettavin tapa korjata laajoja kallon luukudoksen puutoksia on perinteisesti ollut potilaan oman luukudossiirteen käyttö. Menetelmän ongelmana on siirteen luovutuskohdan vaurio ja kipu sekä paranemiseen liittyvät ongelmat. Erityisesti lapsipotilailla on haasteena riittävän siirreluumäärän rajoitettu saatavuus. Tästä syystä on pyritty kehittämään korvaavia materiaaleja, jotta vältettäisiin suuriin luusiirteisiin liittyviä ongelmia. Autologiset kantasolut ovat osoittautuneet lupaaviksi kehitettäessä luuta korvaavia hoitomuotoja kallon luupuutosten hoitoon. Tämän tutkimuksen päätavoitteena oli tutkia kokeellisen eläinmallin avulla laajojen, kallokirurgiassa aiheutuvia luupuutoksia vastaavien vaurioalueiden paranemista. Tutkimuksessa testattiin erityyppisiä autogeenisiä luusiirteitä ja rasvakudos- tai luuydinperäisiä kantasoluja, joita kasvatettiin kahden biomateriaalin, trikalsiumfosfaatin ja bioaktiivisen lasin pinnoilla. Tutkimuksessa selvitettiin myös fibriinikudosliiman vaikutusta omakudosluusiirteen paranemiseen. Kudoskasvutekijäproteiinien BMP-2, BMP-7 ja VEGF stimuloivaa vaikutusta kudossiirteiden toimintaan ja luutumiseen selvitettiin myös. Tämän tutkimuksen tulokset tukevat aiemmin raportoituja havaintoja autologisen luusiirrännäisen käyttöön liittyvästä nopeasta resorptiosta. Erityisesti fibriinikudosliiman käytön yhdessä autologisten pienipartikkelisten luusiirteiden kanssa havaittiin heikentävän uuden luun muodostumista kallon luupuutoksissa. Kallon luupuutosten alkuvaiheen paranemisessa rakeinen trikalsiumfosfaatti osoittautui tehokkaammaksi kuin kiinteä säikeinen bioaktiivinen lasi. Samoin rasvakudosperäisten kantasolujen yhdistäminen trikalsiumfosfaattiin lisäsi merkittävästi luun muodostumista verrattuna samaan yhdistelmään bioaktiivisen lasin kanssa. Luuydinperäisiä kantasoluja yhdistettäessä vastaavaa ei voitu tässä tutkimuksessa todeta. Tutkimuksessa kasvutekijöiden käytöllä ei havaittu olevan positiivista vaikutusta kallonluiden paranemiseen.
423

Les contrats de vente d'équidés de sport et de courses / Contracts for the sale of sport and racing horses

Duteil, Margaux 08 December 2016 (has links)
À l’heure actuelle, les équidés font l’objet d’intérêts nombreux en tant que richesse patrimoniale. Ces attributs conférés par le droit de propriété permettent l’établissement de conventions de natures variées, comme la vente. L’intérêt est donc de révéler pourquoi l’établissement d’une vente (à l’essai, à l’amiable, aux enchères publiques ou privées, sur internet, judiciaires volontaires ou forcées, après saisie ou à réclamer) sur un équidé soulève tant de difficultés depuis quelques années. La vente de chevaux est soumise à l’interaction de plusieurs codes (Code civil, Code rural, Code de la consommation). Ces textes prévoient de nombreuses divergences avec un meuble inanimé. Parallèlement, la pratique a mis en place des techniques (comme la visite vétérinaire qui précède l’achat) permettant aux contractants de s’engager en connaissance de cause. Par ailleurs, l’application d’une garantie de deux ans (véritable frein à la vente de chevaux) prévue par le code de la consommation dans les ventes conclues entre un professionnel vendeur et un acquéreur amateur. Par conséquent, la multiplicité des qualifications juridiques, en général, et la soumission à des garanties inadaptées, en particulier, incitent le vendeur professionnel à s’évincer des conventions. Désormais, le meilleur gage de protection consisterait à rédiger très précisément le contrat / At present, horses are the subject of many interests as heritage wealth. These attributes conferred by the right of ownership allow the establishment of conventions of various natures, such as sale. The interest is therefore to reveal why the establishment of a sale (trial, amicable, public or private auctions, on the internet, voluntary or forced judicial, after seizure or to claim) on an equine raises so many difficulties in recent years. The sale of horses is subject to the interaction of several codes (civil code, rural code, consumer code). These texts foresee many divergences with an inanimate piece of furniture. At the same time, the practice has put in place techniques (such as the veterinary visit that precedes the purchase) enabling contractors to make an informed commitment. Moreover, the application of a two-year guarantee (a true brake on the sale of horses) provided for by the consumer code in sales between a sales professional and an amateur purchaser. Consequently, the multiplicity of legal qualifications, in general, and the submission to inadequate guarantees, in particular, incite the professional seller to vindicate conventions. From now on, the best guarantee of protection would be to write the contract very precisely
424

Návrh metodiky řízení a správy incidentů a problémů a jejího využití ve vybrané organizaci / Design of methodology of administration and management of issues and its application in chosen organisation

Holub, Adam January 2016 (has links)
This thesis is focused on design methodology of administration and management of issues, using issue-tracking system. The objective is to create such methodology and deploy it to specific organization. During methodology creation, there were used best practices, acquired from source thesis and authors experiences. In theoretical part of thesis are described approaches, witch is this thesis based on. Then thesis describes what issue-tracking system is and lists mostly used issue-tracking systems. In practical part, the methodology itself is created. At first, target group is described. Then, types of issuse and roles used in issue-tracking system are described. Then is described, how to create lifecycle of issue and how to handle with its attributes. Last part is focused on data reporting from issue-tracking system. Last chapter of practical part describes how to implement methodology to issue-tracking system JIRA.
425

Metodika testování podle mezinárodních praktik a standardů / Testing methodology according to international practices and standards

Králová, Iveta January 2012 (has links)
There are many methodologies in the field of software engineering that focus on the entire software development process. The software development process aims to provide a quality product that meets user requirements, and to deliver it on time as well as within budget. Testing is a tool for verifying the quality of software and serves as feedback in software development. Most software development methodologies are available only in English, they emphasize the actual software development and address testing only marginally. An accurately designed testing process however, may contribute to higher software quality and avoid potential problems resulting from the entire information system's failure. Current Czech methodology that focuses exclusively on testing has been developed either inside individual companies and thus is not accessible to the public, or is contained in graduate theses, where it was typically created by adapting and expanding the existing software development methodologies for testing within a particular company or team. The main objective of this thesis is to establish a methodology for testing in Czech, which is based on international practices and standards, which is not tailored to a specific organization and which can be used as guidance in defining test processes in various organizations, regardless of their specific focus. The proposed methodology is also implemented in the tool EPF Composer that enables administration of methodology and its publication in the form of the website. The thesis also pursues additional objectives. In order to verify the objective of developing a standardized testing methodology is met, the thesis strives to produce a subsequent evaluation methodology using a standardized process framework in order to improve the testing process as well as a summary detailing which areas may be the subject of further expansion methodology. The theoretical part of the thesis aims to evaluate software development methodologies in terms of testing, to provide an overview of standards related to testing and to describe selected standards, to clarify the purpose of certification in testing and to analyze the possibilities of utilizing materials to prepare for the ISTQB certification. The objectives were achieved by analyzing the available materials for ISTQB certification, analyzing software development methodologies, standards, the TMMi procedural framework and other resources that deal with testing as well as its methodologies and standards. The main contribution of this work is a testing methodology, which is based on the testing process as defined by the international organization ISTQB. It provides a methodological framework by interconnecting and expanding individual methodological elements. Elements of the methodology include working products, as specified by the methodology with respect to the IEEE 829 standard. The methodology does not depend on the needs of a particular company and may be easily adopted, managed and customized. It may be used as a starting point in creating a testing strategy in Czech companies focused on software development which are interested in approaching testing in compliance with international practices.
426

Influência da associação da sinvastatina à matriz de osso desmineralizado bovino na reparação de defeitos ósseos em calvária de ratos

Carlos Eugenio Villaboim de Castro Lima 30 June 2008 (has links)
A reparação de defeitos ósseos é uma preocupação constante em diversas áreas da odontologia. Vários materiais são usados com a finalidade de ajudar e acelerar esta reparação, tais como enxertos autógenos, xenógenos, membranas e alguns medicamentos, assim como a associação de alguns destes métodos. A sinvastatina, medicamento utilizado para redução de colesterol, em alguns estudos, tem demonstrado ação na estimulação de formação óssea. O objetivo do presente estudo foi avaliar a influência da associação da sinvastatina à matriz desmineralizada de osso bovino na reparação de defeitos ósseos em calvária de ratos. Foram confeccionados defeitos ósseos na calvária de 48 ratos, sendo um defeito 5mm de diâmetro em cada parietal do animal. Os ratos foram divididos em três grupos de acordo com o material utilizado: grupo controle, que não recebeu nenhum tipo de substância, grupo sinvastatina-matriz óssea desmineralizada, que recebeu uma associação de sinvastatina e matriz desmineralizada de osso bovino e grupo matriz óssea desmineralizada que recebeu somente matriz desmineralizada de osso bovino como material de enxertia. Os sacrifícios foram realizados após trinta e sessenta dias. Após o sacrifício as calvárias foram radiografadas em aparelho de raios-X digital para análise de densidade radiográfica em tons de cinza e foram submetidas à preparação histológica de rotina, para posterior análise histológica descritiva e histométrica da área de matriz óssea neoformada, utilizando-se programa computacional para análise de imagens. Os dados submetidos à analise estatística ANOVA a 5% demonstraram que os animais que receberam a associação de sinvastatina-MODB apresentaram, na análise histométrica a menor área de neoformação e na análise radiográfica a menor densidade óssea. Concluiu-se, de acordo com a metodologia utilizada, que a associação sinvastatina-MODB influenciou negativamente o reparo ósseo. / Bone defect healing is a constant concern to several areas of Dentistry. A great variety of materials is currently used to help in the healing process as well as to speed it up. Materials such as autografts, xenografts, membranes, some drugs, and the association of some of them are being used. Simvastatin, a substance used to reduce cholesterol levels, has shown, in some studies, a capacity to stimulate bone formation. The purpose of the present experimental study is to evaluate the influence of the association of sinmvastatin with bovine demineralized bone matrix on the healing of bone defects in rats calvariae. Bone defects were produced in the calvariae of 48 rats, thus each animal had a defect in each parietal bone measuring 5mm of diameter. The rats were grouped according to the graft material used: the control group which didnt receive any substance; the simvastatin-demineralized bone matrix group which received an association of simvastatin and bovine demineralized bone matrix; and the demineralized bone matrix group which received bovine demineralized bone matrix. The animals were sacrificed after thirty or sixty days. After the sacrifices, digital radiographies were taken of the calvariae in order to analyse the radiographic density in shades of gray. They were also submitted to routine histological preparation for future descriptive histological and histomorfometric analyses of the new formed bone matrix through the use of a software to analyse the images. The data submitted to statistical analysis ANOVA (5%) showed that the animals which received the association simvastatin-demineralized bone matrix presented the smallest density and area of new bone formation of the three groups. According to the methodology used, we concluded that the association simvastatin demineralized bone matrix influenced negatively the bone healing.
427

Non-Syndromic atrioventricular septal defects: a refined definition, associated risk factors, and prognostic factors for left atrioventricular valve replacement following primary repair

Patel, Sonali Subhashchandra 01 December 2010 (has links)
Congenital heart defects (CHDs) constitute a major proportion of clinically significant birth defects and are an important component of pediatric cardiovascular disease. Atrioventricular septal defects (AVSDs) include a range of anomalies characterized by atrial, ventricular, and atrioventricular (AV) valve defects. AVSDs commonly occur in the presence of a syndrome, most frequently Down syndrome; they also occur in isolation and are referred to as non-syndromic AVSDs (NSAVSDs). These studies were performed to evaluate for presence of an intermediate phenotype in parents and siblings of a child with a NSAVSD, risk factors associated with NSAVSDs, and prognostic risk factors for left AV valve replacement following primary repair of an AVSD. It was shown that the mean body surface area-standardized AV septal length (AVSL) was significantly shorter in the NSAVSD parents and siblings than in parents and siblings of syndromic AVSD case and control children. Using age- and gender-adjusted body surface area-standardized AVSL, it was determined that there was evidence for two component distributions in parents and siblings of NSAVSD children, suggesting the presence of an intermediate. Broadening the definition of AVSD to include those with a shortened AVSL may increase the power of genetic association and mapping studies to identify susceptibility genes. Risk factors associated with NSAVSD were examined using the 1997-2005 National Birth Defects Prevention Study database. Mothers who actively smoked or were exposed to passive smoke anytime from one month prior to pregnancy through the end of the first trimester were more likely to have an infant with a NSAVSD. There was a suggestive association between AVSDs and use of antibacterial, antifungal, and antiviral medications. Additional investigations are warranted to investigate associations with specific medications as well as to uncover possible gene-environment interaction effects that may modify these risks in order to develop improved primary prevention strategies. Using the Pediatric Cardiac Care Consortium database, factors associated with time to first reoperation and time to replacement following primary AVSD repair were evaluated. Type of AVSD repair, closure of the mitral valve cleft, moderate to severe postoperative left AV valve regurgitation, and presence of postoperative complete heart block were associated with earlier time to reoperation after adjusting for age and weight at AVSD repair. Down syndrome and presence of postoperative mitral stenosis were associated with earlier time to replacement. Prognostic risk factors following left AV valve replacement in children who had previously undergone AVSD repair were also identified. A prosthetic valve size to body weight ratio of greater than 3 and the presence of Down syndrome were identified as predictors of in-hospital death following left AV valve replacement. By adding to our knowledge of the AVSD familial and environmental risk factors from these studies, we will be able to (1) improve genetic counseling, (2) identify other family members for genetic testing, (3) begin to devise primary prevention strategies, and (4) improve treatment modalities. By recognizing prognostic factors which influence survival, optimal patient care can be devised which will not only improve treatment modalities, but also long-term survival.
428

Toward a systematic discovery of artificial functional ferromagnets and their applications

Botsch, Lukas 10 August 2021 (has links)
Although ferromagnets are found in all kinds of technological applications, their natural occurrence is rather unusual because only few substances are known to be intrinsically ferromagnetic at room temperature. In the past twenty years, a plethora of new artificial ferromagnetic materials has been found by introducing defects into non-magnetic host materials. In contrast to the intrinsic ferromagnetic materials, they offer an outstanding degree of material engineering freedom, provided one finds a type of defect to functionalize every possible host material to add magnetism to its intrinsic properties. Still, some controversial questions remain: What are the mechanisms behind these ferromagnetic materials? Why are their magnetization values reported in the literature so low? Are these materials really technologically relevant ferromagnets? In this work, we aim to provide a systematic investigation of the phenomenon. We propose a universal scheme for the computational discovery of new artificial functional magnetic materials, which is guided by experimental constraints and based on first principles. The obtained predictions explain very well the experimental data found in the literature. The potential of the method is further demonstrated by the experimental realization of a truly 2D ferromagnetic phase at room temperature, created in nominally non-magnetic TiO$_2$ films by ion irradiation, which follows a characteristic 2D magnetic percolation transition and exhibits a tunable magnetic anisotropy. Furthermore, the technological relevance of these artificial ferromagnetic materials, which comes to shine when one combines the engineered magnetic with some of the intrinsic properties of the host material, is demonstrated by creating a spin filter device in a ZnO host that generates highly spin-polarized currents even at room temperature.:1 Introduction 2 Computational discovery of artificial ferromagnets 2.1 Ferromagnetism in solids 2.1.1 Exchange interaction and magnetic order 2.1.2 Artificial magnetism due to defects 2.2 Predicting defect structures from collision cascades 2.3 Finding magnetic defect candidates 2.4 Magnetic percolation 2.5 Magnetic phase diagram of anatase TiO 2 artificial ferromagnet 2.5.1 Defect creation in anatase TiO 2 2.5.2 Magnetic properties of dFP defects in anatase TiO 2 2.5.3 Constructing a magnetic phase diagram 2.6 Revisiting prior experimental results 3 Artificial ferromagnetism in TiO 2 hosts 3.1 Low energy ion irradiation 3.2 SQUID magnetometry 3.3 Experimental realization of an artificial ferromagnet in TiO2 4 Artificial magnetic monolayers and surface effects 4.1 Critical behavior and 2D magnetism 4.2 Magnetic anisotropy 4.2.1 Demagnetizing field and magnetic shape anisotropy 4.2.2 Magnetocrystalline anisotropy 4.3 Artificial ferromagnetic monolayer at TiO 2 surface with perpendicular magnetic anisotropy 4.4 DFT calculations of the defective anatase TiO 2 [001] surface 5 Spin transport through artificial ferromagnet interfaces 5.1 Artificial ferromagnetism in ZnO hosts 5.2 Spin filter effect at magnetic/non-magnetic interfaces in ZnO 5.2.1 The spin filter effect 5.2.2 Lithium and hydrogen doping in ZnO 5.2.3 Magneto-transport in artificial ferromagnetic Li:ZnO microwires 5.2.4 Spin transport through magnetic/non-magnetic interfaces 5.2.5 Minority spin filter effect 6 Conclusions and Outlook Bibliography Appendix: A List of publications B Computation inputs and codes B.1 DFT electronic structure calculations - Fleur input files B.2 Magnetic Percolation simulations B.3 SQUID raw data analysis code B.4 SRIM Monte Carlo binary collision code automation / Obwohl Ferromagnete in allen möglichen technischen Anwendungen zu finden sind, ist ihr natürliches Vorkommen eher ungewöhnlich, da nur wenige Stoffe bekannt sind, die bei Raumtemperatur intrinsisch ferromagnetisch sind. In den letzten zwanzig Jahren wurde eine Fülle neuer künstlicher ferromagnetischer Materialien durch das Einbringen von Defekten in nichtmagnetische Wirtsmaterialien entdeckt. Im Gegensatz zu den intrinsischen ferromagnetischen Materialien bieten sie einen herausragenden Grad an materialtechnischer Freiheit, vorausgesetzt man findet zu jedem möglichen Wirtsmaterial einen passenden Typus von Defekten, um dessen intrinsische Eigenschaften um Magnetismus zu ergänzen. Dennoch bleiben einige kontroverse Fragen bislang unbeantwortet: Welche Mechanismen stehen hinter diesen ferromagnetischen Materialien? Warum werden ihre Magnetisierungswerte in der Literatur meist so niedrig angegeben? Sind diese Materialien wirklich technologisch relevante Ferromagneten? In dieser Arbeit wollen wir eine systematische Untersuchung des Phänomens durchführen. Wir schlagen ein universelles ab-initio Protokoll für die computergestützte Entdeckung von neuen künstlichen funktionalen magnetischen Materialien vor, das sich an experimentellen Bedingungen orientiert. Die erhaltenen Vorhersagen erklären die in der Literatur gefundenen experimentellen Daten sehr gut. Wir demonstrieren die Wirksamkeit der Methode durch die experimentelle Realisierung einer echten 2D-ferromagnetischen Phase bei Raumtemperatur, die in nominell nicht-ma'-gne'-tischen TiO$_2$-Filmen durch Ionenbestrahlung erzeugt wird. Die so entstehende ferromagnetische Phase folgt einem charakteristischen zweidimensionalen magnetischen Perkolationsprozess und weist eine steuerbare magnetische Anisotropie auf. Weiterhin wird die technologische Relevanz dieser künstlichen ferromagnetischen Materialien gezeigt, welche besonders zum Vorschein kommt, wenn man die künstlichen magnetischen mit einigen der intrinsischen Eigenschaften des Wirtsmaterials kombiniert, und zwar indem ein Spin-Filter Element auf Basis eines ZnO-Wirts gebaut wird, das selbst bei Raumtemperatur hoch spin-polarisierte Ströme erzeugt.:1 Introduction 2 Computational discovery of artificial ferromagnets 2.1 Ferromagnetism in solids 2.1.1 Exchange interaction and magnetic order 2.1.2 Artificial magnetism due to defects 2.2 Predicting defect structures from collision cascades 2.3 Finding magnetic defect candidates 2.4 Magnetic percolation 2.5 Magnetic phase diagram of anatase TiO 2 artificial ferromagnet 2.5.1 Defect creation in anatase TiO 2 2.5.2 Magnetic properties of dFP defects in anatase TiO 2 2.5.3 Constructing a magnetic phase diagram 2.6 Revisiting prior experimental results 3 Artificial ferromagnetism in TiO 2 hosts 3.1 Low energy ion irradiation 3.2 SQUID magnetometry 3.3 Experimental realization of an artificial ferromagnet in TiO2 4 Artificial magnetic monolayers and surface effects 4.1 Critical behavior and 2D magnetism 4.2 Magnetic anisotropy 4.2.1 Demagnetizing field and magnetic shape anisotropy 4.2.2 Magnetocrystalline anisotropy 4.3 Artificial ferromagnetic monolayer at TiO 2 surface with perpendicular magnetic anisotropy 4.4 DFT calculations of the defective anatase TiO 2 [001] surface 5 Spin transport through artificial ferromagnet interfaces 5.1 Artificial ferromagnetism in ZnO hosts 5.2 Spin filter effect at magnetic/non-magnetic interfaces in ZnO 5.2.1 The spin filter effect 5.2.2 Lithium and hydrogen doping in ZnO 5.2.3 Magneto-transport in artificial ferromagnetic Li:ZnO microwires 5.2.4 Spin transport through magnetic/non-magnetic interfaces 5.2.5 Minority spin filter effect 6 Conclusions and Outlook Bibliography Appendix: A List of publications B Computation inputs and codes B.1 DFT electronic structure calculations - Fleur input files B.2 Magnetic Percolation simulations B.3 SQUID raw data analysis code B.4 SRIM Monte Carlo binary collision code automation
429

Vybrané problémy při oceňování stavebních prací pro účely znaleckých posudků / Selected problems in the process of building operation appraisal for the purposes of expert opinions

Novák, Jindřich January 2018 (has links)
The basic requirement for a good quality expert opinion are high quality sources of information, i.e. adequately detailed and valid groundwork. This dissertation analyzes groundwork for expert activities in the area of building operation appraisals, handling of information and its transmission within the life cycle of a construction. For this purpose, it is possible to divide the construction according to its functional parts. The thesis puts emphasis on drawing up a budget according to its functional parts, which is clearer for the investors, contractors and real estate administrators as well as the expert. A significant part of the dissertation is dedicated to recommendations on how to determine the usual price of building operations. In this section I define some options of how to determine the usual price of building operations, including their comparison. Likewise, I investigated and compared real agreed prices of building contracts for public commissions. The basic recommendation resulting from this chapter is the recommendation for the Czech statistics department to automate the data collection based on registers of building operations created with one of the budgeting programs (preferably according to functional parts). For the experts, I prepared a set of recommendations based on the analyzed differences between the budgeted prices and those applied in real contracts. There is no generally accepted method to evaluate the losses created due to delays in construction. For the purposes of this dissertation, I investigated the common prices of rent of the individual equipment and then established two approaches to put value on the cost of equipping the site, percentage rate and individual calculation. I examine in more detail the issues related to quantification of costs for wintertime arrangements. At the end of the chapter I define recommendations for experts. With regard to recommendations for establishing discounts from the construction price due to occurrence of defects and unfinished tasks, I analyzed real examples of distribution of defects and unfinished tasks at the moment of delivering the building operation to the investor and discovered that approximately 50% of defects are part of the surface working. Additionally, I analyzed the Czech technical regulations regarding surface working in order to find basis for assessment of the presence or absence of a defect. While investigating the approach to non-removable defects, I discovered incorrectly considered shelf life of waterproofing within the appraisal. Based on this, I investigated the market and determined the shelf life of common waterproofing systems. At the end of this dissertation I carry out a comparison of selected items of the two pricing systems most commonly used in the Czech Republic, URS and RTS. The differences are a result of contemplating using different technologies, varied mechanisms and diverse approaches to determine the costs of material.
430

C/O+ charge transfer & the Olson-Demkov model

Bengtsson, Kristoffer January 2021 (has links)
Charge transfer reactions and their rates play a key role in correctly estimating element abundances in astrophysical objects such as supernovae. The reaction $C + O^+ \rightarrow C^+ + O(^1D) + \Delta E$ has been shown to be of significance when estimating oxygen abundances through model spectrum evaluations, and the relative rate of this reaction can under certain circumstances completely dictate the neutralization rate of oxygen ions. In this project, the rate of this reaction for four different temperatures is estimated using the Olson-Demkov model to calculate the cross section of the reaction as well as calculating rates for a few more reactions to compare to established literature values.  We find that the Olson-Demkov model produces good estimates for reactions that have small energy defects (within an order of magnitude of more rigorous quantum mechanical calculations), but the model underestimates the rate coefficient by several orders of magnitude as the energy defect increases. As the investigated reactions are all exothermic, the energy defect is the released energy from the reaction (i.e., the energy defect is positive). It is also found in most cases that the Olson-Demkov model rate is poorly estimated by the rate coefficient based only on the cross section at the mean velocity, caused by the cross section rising rapidly for velocities higher than the mean. The rate estimates produced for C+O$^+$ are also likely to be underestimated, especially for the temperatures 100 and 1000 Kelvin. No literature comparison is available for this specific reaction, but this conclusion is consistent with the other investigated reactions. / Supernovor är bland de mest extrema fenomen vi kan observera i hela Universum. Dessa våldsamma explosioner lämnar spår efter sig i många år och har varit ovärdeliga objekt att observera för att lära oss mer hur vår galax och Universum har utvecklats över tid. Ljuset från supernovor och deras kvarlevor kan analyseras för att ta reda på vad för ämnen som finns kvar eller som har bildats av både explosionen och de processer som ägt rum efteråt. En typ av reaktion som är viktig för att fullt ut förstå dessa miljöer är så kallade "laddningsöverföringar", en reaktion där en laddad och en oladdad partikel interagerar med varandra varvid laddningen förflyttas mellan de två. Detta projekt har fokuserat på en modell som avser att räkna ut uppskattningar på hur sannolikt det är för dessa reaktioner att äga rum. Modellen, som kallas för Olson-Demkov-modellen, har även jämförts med andra modeller för att se under vilka förhållanden som den fungerar.

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