Im Rahmen umfangreicher experimenteller Untersuchungen wurden die Bruchspannungen für Textilbeton unter einaxialer, einsinniger Zugbelastung ermittelt. Im Ergebnis liegen variierende Daten vor, die auf eine nichtdeterministische (unscharfe) Bruchspannung hinweisen. Die Versuchsergebnisse stellen eine moderate Datenbasis für eine statistische Auswertung und Quantifikation der Unschärfe dar. Zur Berücksichtigung der unscharfen Bruchspannung bei der Bemessung mittels einfacher Handrechnungen muss ein deterministischer Sicherheitsabstand eingeführt werden. Der Sicherheitsabstand wird in den derzeit gültigen Normen mit Teilsicherheitsbeiwerten festgelegt, die ein ebenso normativ vorgegebenes Sicherheitsniveau gewährleisten sollten. In diesem Kontext werden im Beitrag auf der Basis von Zuverlässigkeitsbetrachtungen ermittelte Teilsicherheitsbeiwerte für Textilbeton mit AR-Glas- und Carbon-Bewehrung vorgeschlagen. / In the framework of a comprehensive experimental program the ultimate strength of textile reinforced concrete has been determined under consideration of uniaxial tensile load. In result varying data are available which indicate a non-deterministic (uncertain) strength. The experimental results provide a moderate basis for statistical evaluations and the quantification of uncertainty. Furthermore, manual calculation in structural design requires a certain safety distance. For this task, partial safety factors have been defined and incorporated in the design codes to ensure a predefined safety level. In this context, this paper gives suggestions for the definition of partial safety factors for textile reinforced concrete with AR glass and carbon reinforcement.

The overall objective of this study was to develop an optimised Ultra-High-Performance Concrete (UHPC) matrix based on the modified Andreasen and Andersen optimum particle packing model by using available South African materials. The focus of this study was to determine the optimum combined fibre and superplasticiser content for UHPC by using a response surface design. The UHPC was appropriately designed, produced and tested. Various changes in mechanical properties resulting from different combinations of steel fibre and superplasticiser contents was investigated. The flowability, density and mechanical properties of the designed UHPC were measured and analysed. Both the fibre and superplasticiser content play a significant role in the flowability of the fresh concrete. The addition of fibres significantly improved the strength of the concrete. The results show that the superplasticiser content can be increased if a more workable mix is required without decreasing the strength significantly. The statistical analysis of the response surface methodology confirms that the designed models can be used to navigate the design space defined by the Central Composite Design. The optimum combined fibre and superplasticiser content depend on the required mechanical properties and cost. Using the modified Andreasen and Andersen particle packing model and surface response design methodology, it is possible to efficiently produce a dense Ultra-High-Performance Fibre Reinforced Concrete (UHPFRC) with a relatively low binder amount, low fibre content and good workability. The effect of heat curing on the mechanical properties was investigated. It was concluded that heat curing is not recommended when considering the long-term strength development. The estimated strength development of concrete obtained by using the fib Model Code 2010 (2013) does not incorporate the detrimental effect of high curing temperatures on long-term strength and therefore overestimate the long-term strengths. The strength estimates for both early and long-term ages can be improved by considering this effect in the strength development functions obtained from fib Model Code 2010 (2013). The effect of specimen size on the compressive and flexural tensile strength of UHPFRC members were established. It was found that the specimen size has a significant effect on the measured cube compressive strength. Smaller beam specimens showed higher ductility compared to those of the larger beam specimens. The crack width decreased as the beam’s depth decreased. A lower variability was experienced in the beams with limited depth (< 45 mm). Further testing is required to determine whether a span-to-depth ratio of 10 would yield optimum results. The utilisation of by-products, such as undensified silica fume and fly ash, as cement replacement materials makes UHPFRC sustainable, leading to a reduced life-cycle cost. The calculated Embodied Energy per unit strength (EE/unit strength) and Embodied Carbon per unit strength (EC/unit strength) values for the UHPFRC mixture yield lower values compared to that of the 30 MPa concrete mixture, indicating that UHPFRC can be used to reduce the environmental footprint of the concrete industry. The inverse analysis method used was successful in providing an improved simplified stress-strain response for the UHPFRC. The analysis provided valuable information into the stress-strain, load-deflection and moment-curvature responses of the UHPFRC. Standard material test results were used to theoretically calculate moment-curvature responses and were then compared to the experimental results obtained. The study demonstrated that it is possible to efficiently produce a dense and workable UHPFRC with relatively low binder amount and low fibre content. This can result in more cost-effective UHPFRC, thus improving the practical application thereof. / Dissertation (MEng)--University of Pretoria, 2020. / Civil Engineering / MEng (Structural engineering) / Unrestricted

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The scope of the presented master thesis was the experimental study of multi-filament yarns made of AR-glass and used for textile-reinforced concrete. The behavior under the tensile loading was investigated by laboratory tests. A high number of yarn specimens (over 300) of six different lengths (from 1 cm to 74 cm) was tested to obtain statistically significant data which were subsequently corrected and statistically processed. The numerical model of the multi-filament bundle was studied and applied for prediction of the yarn performance and for later results interpretation. The model of n parallel filaments describes the behavior of a bundle with varying parameters representing different sources of disorder of the response and provides the qualitative information about the influence of their randomization on the overall bundle response. The aim of the carried experiment was to validate the model presumptions and to identify the model parameters to fit the real load-displacement curves. Unfortunately, due to unsuccessful correction of measured displacements devalued by additional non-linear contribution of the unstiff experiment device the load-displacement diagrams were not applicable to model parameters identification. The statistical evaluation was carried only for the maximal load values and the effect of the specimen size (length) on its strength was demonstrated. The size effect curve did not exclude the existence of spatial correlation of material mechanical properties modifying the classical statistical Weibull theory.

The study deals with mechanical characteristic of heterogeneous weld joint. The low carbon steel 22K and austenitic steel have been used as a experimetnal materials. The low carbon steel has special properties in basic condition. The sample has been evaluated in basic condition and after annealation. There have been evaluated impact of annealation proces to structure and mechanical charakteristics in experimental part of study. The particularised analysis of microstructure has been done by pictorial analysis. Mechanical characteristics has been examinated in both conditions by 2 different methods – measurment of microhardness according to Vickers and test of fracture toughness on compact tension specimens.

The master thesis is focussed on evaluation of mechanical properties and fracture behaviour of basic materials and weld joints of a water turbine supply pipe. The results of tensile tests, fracture toughness tests, hardness and micro-hardness tests and further chemical and metallography analysis are used for operating degradation level evaluation of the construction material and also for a residual operating recognition of the second, identical specimen of supply pipe.

Diploma thesis deals with the influence of various dosing of Reclaimed asphalt pavement (RAP) using modified bitumen on the properties of asphalt concrete (ACO 11+) of cemented by polymer modified bitumen, while a rejuvenating agents are added into asphalt mixtures. The theoretical part of the thesis summarizes the basic knowledge of pavement recycling, polymer modified bitumens and their reuse in asphalt mixtures. The practical part deals with laboratory tests of ACO 11+ mixtures with the RAP proportion of 0 % to 50 %. The asphalt mixtures compared are evaluated by means of the Thermal Stress Restrained Specimen Test (TSRST) and Stiffness test. The results obtained within the diploma thesis can approximate the issue of recycling of asphalt mixtures with polymer modified bitumens.

We have compared two gastric string tests for obtaining gastric juice for culture of Helicobacter pylori and for nested-PCR detection and PCR-based combined single- and double-stranded conformational polymorphism (SDSCP) discrimination of infecting strains. String test specimens were obtained from one seropositive volunteer for 13 consecutive weeks. The distal 10 cm of each string was suspended in 1 ml saline and quantitatively cultured. An additional nine volunteers with histories of upper-gastrointestinal complaints were given a string test for culture and nested-PCR assay. H. pylori isolates and/or gastric juice from each volunteer were extracted for DNA and analyzed by PCR-based SDSCP. Quantitative culture showed that the Entero-test was four times as sensitive as the Gastro-test but was more prone to contamination by oral flora. However, the two string tests are equally sensitive by PCR assays. Thus, the Gastro-test is more suitable for culture detection of H. pylori, since it is less prone to oral contamination and its shorter length is better tolerated. SDSCP analysis of H. pylori DNA from four PCR-positive volunteers without requiring culture showed four distinct profiles, indicating different infecting strains. SDSCP analysis of strains isolated before and after treatment of one volunteer had the same SDSCP profile, suggesting endogenous reinfection by the same strain.

Finite element analyses are frequently used to model growing fatigue cracks and the associated plasticity-induced crack closure. Two-dimensional, elastic-perfectly plastic finite element analyses of middle-crack tension (M(T)), bend (SEB), and compact tension (C(T)) geometries were conducted to study fatigue crack closure and to calculate the crack opening values under plane-strain and plane-stress conditions. The loading was selected to give the same maximum stress intensity factor in both geometries, and thus similar initial forward plastic zone sizes. Mesh refinement studies were performed on all geometries with various element types. For the C(T) geometry, negligible crack opening loads under plane-strain conditions were observed. In contrast, for the M(T) specimen, the plane-strain crack opening stresses were found to be significantly larger. This difference was shown to be a consequence of in-plane constraint. Under plane-stress conditions, it was found that the in-plane constraint has negligible effect, such that the opening values are approximately the same for the C(T), SEB, and M(T) specimens. Next, the crack opening values of the C(T), SEB and M(T) specimens were compared under various stress levels and load ratios. The effect of a highly refined mesh on crack opening values was noted and significantly lower crack opening values than those reported in literature were found. A new methodology is presented to calculate crack opening values in planar geometries using the crack surface nodal force distribution under minimum loading as determined from finite element analyses. The calculated crack opening values are compared with values obtained using finite element analysis and more conventional crack opening assessment methodologies. It is shown that the new method is independent of loading increment, integration method (normal and reduced integration), and crack opening assessment location. The compared opening values were in good agreement with strip-yield models.

繼人體基因圖譜於2000年解碼後，基因解讀及研究初期均在競爭解讀基因序列(Gene sequences)，然而了解基因序列是一件事，如何從序列中來了解基因功能所賦予之生理生化意義，比如每段基因所產生之蛋白質產物、及蛋白質與細胞之間的相互關係等資訊，進而應用於藥物標的之尋找，才是未來生物醫學發展之主要方向。同理，藉由基因功能學(Functional Genomics)領域來研究新發現之基因的功能、基因表現、與蛋白質產物，進而辨識有用的藥物標的(Drug target)及尋找新的疾病治療方法，才是基因解讀後最主要之生技醫療市場。全球生物科技之應用中以醫療用的生技產品所帶來的產值最為可觀，佔總體生技產業約七成以上之產值，其中又以重組蛋白藥品、單株抗體、疫苗及檢驗試劑之研發為主要重心，其中行政院更在“加強生物技術產業推動方案”裡，特別將蛋白藥物、抗癌藥物開發及檢驗試劑等領域列為重點推動項目，國內外許多生物科技公司研發專長及主軸亦座落於全球最熱門的生技製藥發展脈絡上。目前由於許多癌症、代謝失常疾病、遺傳性疾病及自體免疫疾病等，臨床之治療藥物仍舊是付之闕如或是供不應求，其中特別是各種癌症以及自體免疫疾病，如類風濕性關節炎、多發性硬化症、牛皮癬及過敏等，都是生技醫藥開發非常重要之疾病研究領域。現今臨床上所常用的藥物，普遍有特異性不佳、副作用大的缺點，因此國內外許多生物科技公司正戮力於針對上述疾病類別找尋合適之生技藥物或是小分子藥物，已達到標的治療(Target therapy)為目的；然而在生技醫藥公司草創初期，大都以技術掛帥，且由於藥品開發時間冗長，因此鮮少有生技醫藥公司能於設立初期10年內有產品上市，因此導致初期營運風險居高不下，令投資者裹足不前，所以如何評估具有成長潛力之生技醫藥公司頗為困難，因此本論文擬從生技藥品著手，除了傳統從技術面、產品面、市場面、競爭者、人力資源、策略經營等構面著手分析成長中之生技醫藥公司外，由於生技醫藥產業之特殊屬性，所以更特別注重產業成長時針對生物倫理面的考量，以做為生技醫藥公司具成長潛力之指標之一。希望透過多元的評估分析，能夠歸納出生技醫藥公司的成功要素，並藉此分析能夠有系統的篩選出具成長性、具社會責任之生技醫藥公司，才能擘畫生技醫藥公司維持長期競爭力、獲得永續發展的遠景，並藉此做為投資者長期投資評估之參考依據。 / The completion of the human genome project is regarded as a turning point in biotechnology and medicine. This project is expected to produce sequence of DNA representing the functional blueprint and evolutionary history of the human species. As we entered the postgenomic era, what we faced is the explosion of new information, which is leading to dramatic changes in the way we are able to study and manipulation of life. At the first few years, many groups were competing in sequence decoding. However, the findings of the functions of genes and the interactions of different gene products are the main issues helping us exploit the new biotechnology markets. Through the research of functional genomics to explore the function, expression, and protein products of novel genes is helpful in identifying new drug targets and developing therapeutic strategies in treating various diseases. This is what we emphasized in biotech market after entering the postgenomic era. The most valuable branch of biotechnology industry is the medical products in global biotechnology market. The medical products take up to 70% of total sales in biotechnology markets. Among the medical biotechnology field, recombinant protein drugs, monoclonal antibodies, vaccines, and detection kits have been focused in pharmaceutical R&D investment. Executive yuan of the Republic of China decided to emphasized in protein drugs, anti-cancer drug development and detection kits in their “ The promotion plan of improving biotechnology industry”. Currently, the drugs against cancers, metabolic diseases, inherited diseases, and autoimmune diseases are still unavailable. Especially the drugs for various cancers, and autoimmune diseases including rheumatoid arthritis, multiple sclerosis, psoriasis, and allergy are under intensive investment in global biotechnology industry. This is because the drugs used today have the deficiencies including low specificity and adverse side effects. Thus, target therapy using monoclonal antibodies and small molecular drugs are the goals for worldwide biotech companies. However, the development in research has been considered as the most important thing in the starting stage of newly founded biotech companies and the long time needed for putting a new drug to market make very few biotech companies have salable products. Thus, the newly biotechnology company has been considered has high risk in the beginning stage. This makes investors to hesitate in putting their money in this field. To evaluate the potential of a new biotechnology companies is difficult since the complex of this industry. This study will try evaluating a newly founded biotechnology company not only through technology, product, market, competitors, human resources, strategies, but also from the consideration in bioethics. Hopefully, through the evaluation of multiple markers, we can conclude the essential factors for a successful company and screen out the company with high growing potential via this study. Finally, this study might serve as a reference for investors in evaluating a promising company for long-term investment.