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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.
261

Tubular Tissue Engineered Scaffold-Free High-Cell-Density Mesenchymal Condensations For Femoral Defect Regeneration

Varghai, Daniel 30 August 2017 (has links)
No description available.
262

Management of Sclerotinia stem rot of soybean and diversity of Pythium irregulare in Ohio

Huzar Novakowiski, Jaqueline January 2017 (has links)
No description available.
263

智慧財產權管理策略研究-以模具業及其關連高科技產業為例 / Study on Strategy of Intellectual Property Rights Management: Taiwan Mold and Die Industry and Its Related High-tech Industry

廖文璋, Johann Liaw, V. C. Unknown Date (has links)
台灣模具產業具有交期短、品質好、價格具有競爭力、製程安排彈性大等優勢,因此在高科技產業供應鍊中扮演關鍵性的角色。唯近年來,台灣許多高科技產業的外移,造成模具業產值最近連續三年呈現下降與核心技術外流,成為模具業所面臨的嚴重考驗。如何留住核心技術人才,加強研發新的關鍵技術並將研發成果取得智慧財產權相關法律保護,並以必要的組織、制度、人才、措施等妥善加以管理,已經成為模具業以及關連高科技產業必須面對的重要課題之一。 本研究以策略管理的角度切入,探討由策略前提所形成之策略,與智慧財產權管理實際運作下,對「台灣模具業及其關連高科技產業的智慧財產權管理發展現況及當前問題」提出適當建議與解決之道。 研究對象為台灣五家經營績效良好之模具業者及關連高科技業者。模具業者包含金屬沖壓、塑膠射出成型、與壓鑄模具業者;關連高科技業者則包含連接器、筆記型電腦、與行動電話業者。其中三家模具業者尚未擁有專利保護,而兩家關連高科技業者之專利保護已有相當成效。本研究主要發現如下: 一、不同的企業規模,對改善技術能力作法有其差異: (一)共同研發新技術:中小企業傾向與國內研發機構共同研發,並取得新技術之全部或部份智慧財產權或取得授權使用新技術;大型企業則傾向自行研發為主。 (二)自國外引進新技術:中小企業傾向委託財團法人或智財科技服務公司從技術先進國家引進技術;大型企業則傾向自行引進技術為主。 (三)向技術相對落後國家移轉技術方面: 1.中小企業傾向透過財團法人或智財科技服務公司之協助移轉技術,對於較單純之案件可自行為之。 2.大型企業可自行為之或採上述方法,委託專業之單位或公司為之。 3.台灣企業對大陸投資之子公司,大部分並未針對技術移轉收取權利金,僅由子公司之獲利盈餘分配取得回饋,尤以持股比例較大者最為普遍。 二、國內模具業及關連高科技產業智慧財產權管理現況為: (一)制定「營業秘密管理辦法」,規範各業務或利害關係人之營業秘密保護要項: 1.影響製造精度之技術 2.訪客參訪流程與動線 3.與供應商相關之營業秘密 4.顧客之營業秘密 5.矯正預防措施單 (二)制訂「專門技術管理辦法」,加強專門技術保護 1.規範「提案改善制度」 2.培養技術專家 3.掌握專門技術人力資源,塑造: (1)尊重專業 (2)對等報酬 (3)生涯規劃等制度完善之企業文化。 (三)專利管理制度: 1.建立提案與獎勵制度: 對創新提案、申請專利、專利核准、與達成技術移轉等階段均核發獎金,以鼓勵員工技術創新。 2.專利維護: 對專利佈局同時重質與量之提升,專利權之維護,則以成本效益為主要考量,以具市場價值者為優先申請與維護對象。 (四)技術授權考量有二: 1.視技術生命週期採行不同之授權策略,如導入與成長期採技術引進、成熟期採交互授權、衰退期技術則對外移轉。 2.以對子公司持股比例,調整技術移轉之權利金分配,持股較高則以盈餘分配取代權利金,持股較低則傾向依市場機制收取權利金。 由本研究之策略意涵得知,個案公司目前所採行之策略,均能適當地反映出其目前所處環境。如鴻海精密以綿密之專利佈局保護其技術,鉅祥、竣盟、谷崧則實施營業秘密與專門技術管理,神達機構則是專利保護與營業秘密管理兼具。 由此可知,模具業及關連高科技產業之智慧財產權管理作法具有多種不同之形式,專利保護並非模具業與關連高科技產業智慧財產權管理之唯一解答。尤其對中小企業而言,注重營業秘密與專門技術保護,塑造良好的企業文化、工作環境,設計合理對等報酬、制度完備的人力資源管理措施,亦不失為智慧財產權管理的良好解決方案之一。 目前大型之關連高科技企業非常重視智慧財產權,並已發展出一套以專利保護為主軸的管理制度。展望未來,模具業與關連高科技產業之連動性將逐漸加深,模具業者今後亦必須加快建立智慧財產權管理制度之腳步。 / Taiwan's mold & die industry plays a very important role of the supply chain for the high-tech industry around the world due to its advantages of short delivery time, good quality, competitive price and production flexibility, etc. However, in recent years, the continuing migration of the high-tech industry is resulting in production decreases and movement of core technology out of Taiwan. How should we keep the core technology, human and financial resources left in Taiwan; what can be done to strengthen research and development (R & D) on new and core technology; how can the core technology be protected by patents managed by a sever system. This is a matter of great urgency and an important issue that Taiwan’s mold & die industry and its related high-tech industry are facing. In view of the above, this study offers Taiwan's mold & die industry and its related high-tech industry some suggestions and solutions for the problems that they faced, based on their current Intellectual Property Rights (IPR) management development situation. This study was researched from the strategy management view and included five (5) outstanding mold & die manufacturers and their related high-tech companies in Taiwan. These mold & die manufacturers are in the metal stamping die, plastic injection mold and die casting mold industries; these high-tech companies are in the connectors, notebook computer and cellular phone (telecommunication) industries. Three of the companies, the mold & die manufacturers, do not hold any patents, while the other two high-tech companies are well protected by their patents. The main finding of this research is as follows: 1.The strategy of technical improvement for companies of various sizes is different: 1) R & D for new technology- Small and medium companies prefer to cooperate with other local R & D institutes in developing, researching, and obtaining full or partial intellectual property rights protection; or obtaining the rights to use the new technology (invention). On the other hand, large companies tend to do the R & D in-house. 2) Technology transfer from overseas– Small and medium companies prefer to transfer the technology from high-tech orientated countries through local R&D institutes or an IPR service provider. However, large companies prefer to transfer the new technology by themselves. 3) Technology transfer to developing countries– (1) Small and medium companies tend to transfer the technology to developing countries through local R&D institutes or IPR service provider except in the case of simple projects. (2) Large companies tend to transfer their technology out by themselves or through a professional agency. 2.The IPR management situation of Taiwan’s mold & die industry and its related high-tech industries– 1) Establish “Trade Secret Management Regulations” to prevent the following trade secrets from being disclosed: (1) Technology that will influence the accuracy of machining. (1)-1 On site know-how – Limiting the visitors touring sensitive areas. (1)-2 Trade secrets of suppliers. (1)-3 Trade secrets of customers. (1)-4 Corrective action reports. 2) Establish “ Know-how Management Regulations” to: (1) Regulate “Proposal improvement systems” (2) Train and develop technical specialists (3) Retaining knowledgeable human resources by (3)-1 Professional appreciation (respect) (3)-2 Equal award (return) (3)-3 Good and complete system, employees’ career planning and enterprise culture. 3) IPR management system: (1) Establish a proposal and reward system: Encourage employees’ technology inventions by rewarding them for their proposals, applications, and completion of technical transfer for IPR. (2) Patent protection: Consider not only the number of patents, but also the quality of patents. 4) Technology transfer policy Different policy for different technique life cycle. From this research, we realized that companies apply different strategies in response to their recent situation. For example, “Hong Hai” is applying the practice of IPR management in protecting his technology; G-Shank, Giant Union and Coxon are applying the practice of trade secret and know-how management; MiTac is applying the practice of both IPR management and trade secret management. From the above, we also realize that patent protection is not the only solution for IPR management in the mold & die industry and it’s related high-tech industries. Trade secret management and know-how protection, a good corporate culture, good business and human resource management, an improved working environment, reasonable and rewarding work are also the major solutions for IPR management. For the time being, large high-tech companies highly respect IPR and have developed a good management system, especially for patent protection. Therefore, due to the close relationship between the mold & die industry and high-tech industries, speeding up the development of IPR management becomes an urgent issue for the mold & die industry.
264

Os caminhos da formação de gestores de Sistemas e Serviços de Saúde: uma análise da adequação entre a teoria e a prática. / Paths management, training, for system and health services managers: an analysis of adequacy between theory and pratice

Cledenir Formiga Casimiro 17 May 2011 (has links)
Caminhos da formação de gestores de sistemas e serviços de saúde: uma análise da adequação entre teoria e a prática?. O cotidiano da gestão dos sistemas serviços de saúde é constituído de questões que perpassam o contexto das políticas econômicas, interagem com as faces das incorporações tecnológicas, estando intimamente relacionado ao componente regional e social. Nesse ambiente de alta labilidade torna-se importante a utilização de mecanismos que reforcem a interação entre educação e trabalho. A responsabilidade da formação profissional deve relacionar-se aos resultados das necessidades da assistência à saúde, guiadas pelos resultados de avaliações sistemáticas. O objetivo principal desta tese consistiu em analisar a adequação do conteúdo teórico representado nas dimensões de competências do Curso de Especialização em Gestão em Saúde do IMS/UERJ face às reais necessidades de aplicação das competências gerenciais dos egressos no desempenho de suas funções no dia a dia de trabalho. O estudo a adequação dos conteúdos educacionais ás necessidades contextuais dos processos de trabalho, importa na leitura das condições de enfrentamento dos problemas cotidianos, as dificuldades ou facilidades de soluções podem variar em função do nível de apropriação dos saberes trabalhados no processo aprendizagem. Ainda que as dificuldades da gestão no ambiente da saúde não resultem apenas de fatores ligados á formação profissional, essa vertente precisar ser monitorada visando contribuir com as reais necessidades de desempenho dos gerentes. Tais necessidades podem ser facilitadas pelo aumento da capacidade de análise contextuais e pelo domínio de manuseio de ferramentas técnicas que se configurem como instrumentos de resolução de problemas na realidade cotidianas. A partir do problema pesquisado, e dos resultados encontrados foi possível concluir, respondendo às questões de partida: (i) O curso de Especialização em gestão de saúde do IMS/UERJ atende as necessidades de desempenho profissional de seus egressos em suas funções cotidianas gerenciais considerando as respostas destes, classificando em mais 80% das dimensões de competência componentes do conteúdo programático como muito importante e indispensável no desempenho pratico de suas funções cotidianas. (ii) Os ajustes á serem inseridos ao conteúdo programático do Curso de Especialização em Gestão de Saúde, segundo seus egressos, e demais entrevistados para o atendimento das reais necessidades de capacitação dos gerentes de sistemas e serviços de saúde, está configurado nas considerações finais desta tese. Os resultados dessa tese oferecem subsídios para formulação de conteúdo programático que fomentem as necessidades de profissionalização da gestão na saúde. O estudo dessas situações, no campo prático, aponta perspectivas positivas com a busca de aperfeiçoamento de programa de capacitação de gestão de saúde e, por conseguinte representa um investimento importante para a melhoria da assistência à saúde da população.
265

Os caminhos da formação de gestores de Sistemas e Serviços de Saúde: uma análise da adequação entre a teoria e a prática. / Paths management, training, for system and health services managers: an analysis of adequacy between theory and pratice

Cledenir Formiga Casimiro 17 May 2011 (has links)
Caminhos da formação de gestores de sistemas e serviços de saúde: uma análise da adequação entre teoria e a prática?. O cotidiano da gestão dos sistemas serviços de saúde é constituído de questões que perpassam o contexto das políticas econômicas, interagem com as faces das incorporações tecnológicas, estando intimamente relacionado ao componente regional e social. Nesse ambiente de alta labilidade torna-se importante a utilização de mecanismos que reforcem a interação entre educação e trabalho. A responsabilidade da formação profissional deve relacionar-se aos resultados das necessidades da assistência à saúde, guiadas pelos resultados de avaliações sistemáticas. O objetivo principal desta tese consistiu em analisar a adequação do conteúdo teórico representado nas dimensões de competências do Curso de Especialização em Gestão em Saúde do IMS/UERJ face às reais necessidades de aplicação das competências gerenciais dos egressos no desempenho de suas funções no dia a dia de trabalho. O estudo a adequação dos conteúdos educacionais ás necessidades contextuais dos processos de trabalho, importa na leitura das condições de enfrentamento dos problemas cotidianos, as dificuldades ou facilidades de soluções podem variar em função do nível de apropriação dos saberes trabalhados no processo aprendizagem. Ainda que as dificuldades da gestão no ambiente da saúde não resultem apenas de fatores ligados á formação profissional, essa vertente precisar ser monitorada visando contribuir com as reais necessidades de desempenho dos gerentes. Tais necessidades podem ser facilitadas pelo aumento da capacidade de análise contextuais e pelo domínio de manuseio de ferramentas técnicas que se configurem como instrumentos de resolução de problemas na realidade cotidianas. A partir do problema pesquisado, e dos resultados encontrados foi possível concluir, respondendo às questões de partida: (i) O curso de Especialização em gestão de saúde do IMS/UERJ atende as necessidades de desempenho profissional de seus egressos em suas funções cotidianas gerenciais considerando as respostas destes, classificando em mais 80% das dimensões de competência componentes do conteúdo programático como muito importante e indispensável no desempenho pratico de suas funções cotidianas. (ii) Os ajustes á serem inseridos ao conteúdo programático do Curso de Especialização em Gestão de Saúde, segundo seus egressos, e demais entrevistados para o atendimento das reais necessidades de capacitação dos gerentes de sistemas e serviços de saúde, está configurado nas considerações finais desta tese. Os resultados dessa tese oferecem subsídios para formulação de conteúdo programático que fomentem as necessidades de profissionalização da gestão na saúde. O estudo dessas situações, no campo prático, aponta perspectivas positivas com a busca de aperfeiçoamento de programa de capacitação de gestão de saúde e, por conseguinte representa um investimento importante para a melhoria da assistência à saúde da população.
266

Řešení přenosu tepla tuhnoucí ocelové soustavy se změnou fáze při pohybujících se okrajových podmínkách / Heat transfer solution of solidifying steel system with phase change with moving edge conditions

Fedorko, Tomáš January 2019 (has links)
Cílem diplomové práce je vytvoření 2D numerického modelu pohybujícího se řezu s proměnnými okrajovými podmínkami skutečné geometrie plynulého odlévání a chlazení předlitku v prostředí MATLAB. Model se zabývá vysoce nelineárními termofyzikálními podmínkami oceli během tuhnutí a chlazení. V práci je simulovaná nejen nelinearita termofyzikálních podmínek, ale také nelinearita při fázové změně. Fázová změna je modelovaná pomocí metody entalpie, metody zdánlivé kapacity a metody teplotního zotavení. Všechny výsledky práce jsou porovnány z více hledisek, jako např. z hlediska přesnosti, rychlosti výpočtu, nebo vhodnosti časového diskretizačního kroku pro nelineární problémy, a paralelizace.
267

Creating material properties for thermoset injection molding simulation process

Tran, Ngoc Tu 17 March 2020 (has links)
Um den Spritzgießprozess zu simulieren, sind korrekte Materialdaten nötig. Diese Daten umfassen Viskositätsmodelle, Wärmekapazitätskoeffizienten, Wärmeleitfähigkeitskoeffizienten, PVT-Modelle und bei reaktiven Materialien Härtungsmodelle. Bei der Spritzgießsimulation von Thermoplasten sind die Materialdaten in der Regel in den Simulationstools verfügbar. Der Anwender kann problemlos Thermoplastmaterialdaten auswählen, die bereits in die Materialdatenbank der Simulationswerkzeuge eingebettet waren, um die gesamten Phasen des Thermoplastspritzgießprozesses zu simulieren. Bei der Duroplastspritzgießsimulation sind nur begrenzt Materialdaten vorhanden und selten aus der Datenbank der Simulationswerkzeuge verfügbar, da sie nicht nur bei der Messung rheologischer und thermischer Eigenschaften, sondern auch bei der Modellierung rheologischer und kinetischer mathematischer Modelle kompliziert sind. Daher ist es notwendig, eigene Materialdaten zu generieren. Um dieses Problem zu lösen, bedarf es einer umfangreichen Wissensbasis bei der Messung von Materialeigenschaften sowie der Erstellung eines Optimierungsalgorithmus´. Um den Prozess des duroplastischen Spritzgießens exakt zu simulieren, bedarf es zudem fundierter Kenntnisse über die Formfüllungseigenschaften dieser Materialien. Die Untersuchung des Fließverhaltens von duroplastischen Spritzgießmassen im Inneren der Kavität ist jedoch nicht ausreichend beschrieben. Bisher gab es noch keine veröffentlichten Hinweise, die zeigen, wie man aus experimentellen Messdaten (thermische und rheologische Daten) für den reaktiven Spritzgießsimulationsprozess komplette Materialdaten für Duroplaste erzeugen kann. Diese Probleme führen zu einer Abhängigkeit der Anwender von der Materialdatenbank der Simulationssoftware, was zu einer Einschränkung der Anwendung der Computersimulation in der duroplastischen Spritzgießsimulation und dem Vergleich zwischen experimentellen und Simulationsergebnissen führt. Darüber hinaus stellt sich die Frage, ob es beim Füllen der Kavität ein Wandgleiten zwischen Duroplastschmelze und Wandoberfläche gibt oder nicht. Aus diesem Grund wird die Wirkung des Wandgleitens auf die Kavitätenoberfläche bei der Simulation des duroplastischen Spritzgießens immer noch vernachlässigt. Die vorliegende Arbeit konzentriert sich auf drei wichtige wissenschaftliche Ziele. Das erste ist die Innovation eines neuen technischen Verfahrens zur physikalischen Erklärung des Formfüllverhaltens von duroplastischen Spritzgießmassen. Das zweite Hauptziel ist die Entwicklung einer numerischen Methode zur Erstellung eines duroplastischen Materialdatenblattes zur Simulation der Formfüllung von duroplastischen Spritzgießmassen. Schließlich wird die Erstellung von Simulationswerkzeugen auf der Grundlage der physikalischen Gegebenheiten und des erzeugten Materialdatenblattes durchgeführt. / To simulate the injection molding process, it is necessary to set material data. The material data for an injection molding process must include a viscosity model and its fitted coefficients, heat capacity coefficients, thermal conductivity coefficients, a PVT model and its coefficients, a curing model and its coefficients (only for reactive injection molding). With thermoplastics injection molding simulation, the material data is generally available from simulation tools. Users could easily choose thermoplastics material data that was already embedded in the material data bank of simulation tools to simulate the entire phases of thermoplastics injection molding process. However, with thermosets injection molding simulation, the material data is found in limited sources and seldom available from data bank of simulation tools because of complication not only in rheological and thermal properties measurement but also in modeling rheological and cure kinetics mathematical models. Therefore, with thermoset injection molding compounds that its material data bank has not been found in data bank of simulation tools, before setting material data, it is necessary to create its own material data that simulation packages do not supply a tool. Therefore, to solve this problem, it requires an extensive knowledge base in measurements of material properties as well as optimization algorithm. In addition, to simulate exactly the thermosets injection molding compound process, it requires a profound knowledge in the mold filling characteristics of thermoset injection molding compounds. However, investigation of flow behavior of thermosets injection molding compounds inside the mold has not been adequately described. Up to now, there has not been any article that shows a complete way to create thermoset material data from measured experimental data (thermal data and rheological data) for the reactive injection molding simulation process. These problems are leading to the users ‘dependency on the material data bank of simulation tools, leading to restriction in application of computer simulation in the thermoset injection molding simulation and comparison between experimental and simulation results. Furthermore, there is still a big question related to whether there is or no slip phenomenon between thermosets melt and the wall surface during filling the cavity, for which has not yet been found an exact answer. Because of this the effect of wall slip on the cavity surface is still ignored during thermoset injection molding simulation process. This thesis focused on three key scientific goals. The first one is innovation of a new technical method to explain the mold filling behavior of thermoset injection molding compounds physically. The second key goal is developing numerical method to create thermoset material data sheet for simulation of mold filling characterizations of thermoset injection molding compounds. Finally, creating a simulation tool base on the physical technique and generated material data sheet.
268

Grundlagenuntersuchungen zur Prozess- und Struktursimulation von Phenolharzformmassen mit Kurz- und Langglasfaserverstärkung

Raschke, Kristin 12 June 2017 (has links)
Thermisch und mechanisch hoch beanspruchte Bauteile im Automobil erfordern den Einsatz hochbeständiger Werkstoffe, bei gleichzeitig niedrigen Materialkosten und effizienter Verarbeitung. Rieselfähige Phenolharzformmassen zeichnen dabei eine Werkstoffklasse aus, die aufgrund ihres Eigenschaftsprofils neue Anwendungsbereiche für einen polymeren Werkstoffeinsatz ermöglichen können. Im Rahmen der vorliegenden Arbeit werden im Hinblick auf eine Bauteilentwicklung mithilfe der integrativen Simulation die Grundlagen einer ganzheitlichen Simulationskette der Prozess- und Struktursimulation von rieselfähigen Phenolharzen mit Kurz- und Langglasfaserverstärkung erarbeitet. Das auf Basis umfangreicher Prozessuntersuchungen abgeleitete Strömungsverhalten kann mithilfe des Block-/Scherströmungsmodells beschrieben werden. Die Ergebnisse der Mikrostrukturanalyse zeigen jedoch eine Orientierungsdynamik der Fasern, welche zum gegenwärtigen Zeitpunkt mithilfe der empirischen Modelle der klassischen Spritzgießsolver nicht abgebildet werden kann. Die mikromechanische Materialmodellierung erfolgt entsprechend an der experimentell ermittelten Mikrostruktur, welche die Berücksichtigung von Faserbündelungen und -krümmungen in der mechanischen Strukturanalyse erlaubt. Das abgeleitete elastoplastische Materialmodell wird zur Vorhersage des Ermüdungsverhaltens unter harmonischer und nichtharmonischer Schwingbeanspruchung um ein zyklisches Versagensmodell erweitert, welches eine mittellast- und temperaturunabhängige Berechnung unter Berücksichtigung der Anisotropie ermöglicht. Die Validierung der statischen und schwingenden Beanspruchung erfolgt an einer einfachen Probestabgeometrie sowie einem Strukturbauteil, einem PKW-Motorträger. / Thermally and mechanically highly stressed automotive components require the use of highly resistant materials, with low material costs and efficient processing. Phenolic resin molding compounds represent a class of materials, which can open up new applications for a polymeric material use due to their property profile. In the present work, the fundamentals of a simulation chain of fluid mechanical and structural simulation of phenolic resins with short and long glass fiber reinforcement are developed, with a view to component development using integrative simulation. Based on extensive process investigations the derived flow behavior can be described using the block/ shear flow model. However, the results of microstructure analysis show a dynamic of fiber orientation, which can not be predicted at the present time using the empirical models of classical injection molding simulation. Accordingly, the micromechanical modeling is carried out at the experimentally determined microstructure. That allows the inclusion of fiber bundling and bending in the mechanical structure analysis. The derived elastoplastic material model is extended by a fatigue failure model to predict the fatigue behavior under harmonic and non-harmonic cyclic stress which allows a calculation taking into account the anisotropy, the stress ratio and the temperature. The validation of the static stress and fatigue is performed both on a simple test bar geometry and a structural component, an automotive engine bracket.
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Likvidace biotických škůdců prostřednictvím EMW záření / Disposal of Biotic Pests by EMW Radiation

Sobotka, Jindřich January 2015 (has links)
The possibility of using high-frequency electromagnetic radiation in the construction sector is a common knowledge. Various experiments have been carried out to dry construction materials, or even to destroy biotic pests. However, the majority of these experiments have been executed in laboratory conditions. It means they have been carried out under exact limiting conditions, often very far off those conditions in real building practice. Therefore, this dissertation aims at exploring the possibility of utilizing microwave technology in drying and heating of construction materials, in disposing of biotic pests and sterilizing building materials under real conditions in building practice. The thesis will explain that microwaves are a term given to a part of electromagnetic radiation. Electromagnetic radiation is based on the principle that the radiated energy is absorbed by water molecules present in moist building material. In the mass of the irradiated material, the radiated energy is transformed into thermal energy, where a so-called “motion” of water molecules occurs with the energy then being transformed into kinetic energy. The microwave technology itself offers a very wide range of use, which can be easily achieved, thus making the technology available to use in the future. Part of the experiments and the necessary measurements, too, has been carried out on selected types of building materials in the premises of the Faculty of Civil Engineering of Brno University of Technology. They have been executed under conditions which most closely correspond to the conditions in real buildings. Part of the experiments and the necessary measurements were carried out on particular constructions, by the so-called in situ method. As stated in the conclusion of the dissertation, laboratory measurements and the in situ measurements differ considerably in some cases.
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Metallic nanostructure synthesis using DNA origami molds

Helmi, Seham 14 September 2018 (has links)
The past decade has witnessed a breakthrough in the field of structural DNA nanotechnology, which utilizes DNA molecules as a construction material rather than as simple carriers of the genetic information. With the superior programmability of DNA, sub-nanometer precision in the self-assembly of various complex two- and three-dimensional nanostructures is achievable. It also allows a site-specific placement of different objects and functional groups onto the formed structures. This has enabled the assembly of highly sophisticated nanostructures for various applications. While the field of structural DNA nanotechnology has been astonishingly advancing, many nanoelectronics-relevant structures are made of inorganic materials, and DNA-based nanostructures have shown rather low conductivity. This has limited the use of DNA structures in nanoelectronics and reflected the need for a similar programmable route for the inorganic nanofabrication. A conceivable solution would use DNA nanostructures in a way that will precisely transfer the structural information of the DNA shapes into fabricated metallic nanostructures. One way to do that is to use the DNA nanostructures as templates for external material deposition onto the DNA surface. While this strategy has been effective in proving the concept of DNA-shape transfer, metallic nanostructures fabricated this way have shown some drawbacks, such as showing rough surface morphologies and lacking the required homogeneity for the fabricated metallic structures. An alternative strategy would be to design DNA mold structures that can dictate the shape of metal that is “cast” inside such a DNA container. The main topic of my thesis concerns the second strategy. To discuss this in detail, the structure and some of the important properties of DNA are introduced in section 1.1. In section 1.2 the main milestones in the development of the DNA-nontechnology field are discussed and section 1.3 focuses on previous fabrication approaches of DNA-based metallic nanostructures.

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