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This study uses Monte Carlo simulation to examine the performance of a variable frequency sampling cumulative sum control chart scheme for controlling the mean of a normal process. The study compares the performance of the method with that of a standard fixed interval sampling cumulative sum control chart scheme. The results indicate that the variable frequency sampling cumulative sum control chart scheme is superior to the standard cumulative sum control chart scheme in detecting a small to moderate shift in the process mean.

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In this paper we present a method of synthesizing data in the narrative discourse of two architecture publications, in order to analyze, compare and explore to what extent it is possible to understand a book on different abstract levels using static data. The information in the book is reorganized and shown in different diagrams, used as a didactic visualization method. This allows the representation of a set of kinetic information that cannot be perceived simultaneously.

A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand) in partial fulfilment of the requirements for the degree of Master of Science in Engjneering Johannesburg, 1994 / Recent international investigations into new advanced materials have shown that the intennetallic compound, RuA1, possesses prormising characteristics for high-temperature use in corrosive environments. In order to optimise production of this alloy, an understanding of the Ru-A1 system is necessary. [Abbreviated Abstract. Open document to view full version]

A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering (Metallurgy and Materials Engineering). Johannesburg, March 2014 / This study investigated the C-Ni-V ternary phase diagram and identification of possible abrasive-resistance alloys. Twenty-four alloys were made from the elemental components and were arc-melted under an argon atmosphere, using Ti as an oxygen-getter. These alloys were analysed in both the as-cast condition, and after annealing for 1000oC and water quenching. Microstructural characterization was carried out in a SEM with EDX, and was done to confirm the phases. The results were used to plot a solidification projection and all binary phases extended into ternary, except for ~Ni8V, ~NiV3 and ~V2C which were not found, due to the sample compositions chosen. The extensions of the binary phases were: ~Ni3V: ~15 at.% C; ~Ni2V: ~20 at.% C; σ′: ~18 at.% C; (Ni): ~27 at.% C; ~V8C7: ~2 at.% Ni; ~V6C5: ~2 at.% Ni and ~VC: ~2 at.% Ni. The liquidus surface was derived, and three ternary invariant reactions were identified. The isothermal section at 1000oC was also constructed. Hardness of the alloys was studied in both conditions. Alloys with (Ni) (188-402HV5) were found to be ductile with low hardness. Alloys containing (V), ~Ni3V and ~Ni2V were identified as hard phases (533-1052 HV5). Alloys with σ′ phase were very hard (1065-1266 HV5) extremely brittle with cracks. Fracture toughness of the C-Ni-V alloys 0.9-5.2 (MPa.m-1/2) were comparable with ceramics 0.5-5.3(MPa.m-1/2). The wear behaviour of the alloys was characterized by sliding the carbide alloys against a Cr-steel ball in a pin-on-disc configuration. There were several co-existing wear mechanisms: abrasion, adhesion and the formation of a thin tribolayers. The wear coefficients for a 10N contact load after a sliding wear path of 300m varied between 0.1 x 10-6and 7.6 x 10-6(mm3/Nm), which was not as good as WC-Co hard metals, but close. / MT2017

University of Macau / Faculty of Science and Technology. / Department of Computer and Information Science

Orientador: José Luz Silveira / Banca: Carlos Daniel Ebinuma / Banca: Julio Santana Antunes / Banca: Nathan Mendes / Banca: Electo Eduardo Silva Lora / Resumo: Os sistemas de refrigeração por absorção da mistura amônia-água têm sido amplamente utilizados e referenciados na literatura. Normalmente, os modelos encontrados para análises são baseados considerando-se, dados de tabelas e diagramas para a entalpia em função da concentração. Para a análise de tabelas e diagramas de entropia em função da concentração de amônia na mistura, não se detém a mesma atenção, existindo ausência de dados disponíveis na literatura para esta propriedade termodinâmica. Estes sistemas apresentam-se complexos quanto aos parâmetros físico-químicos, tornando-se necessário um estudo mais aprofundado e detalhado da termodinâmica associada, corroborando para a determinação da inter-relação da entropia com outras propriedades associadas a refrigeração. Neste trabalho são formulados modelos de cálculos para o levantamento da entropia em função da temperatura, pressão e concentração de misturas amônia-água S = S (T, P, x). A confecção dos diagramas de entropia na fase líquido-vapor foram determinados visando auxiliar projetos industriais através de análises energéticas e exergéticas, simulação e otimização de processos relacionados ao sistema de refrigeração por absorção. / Abstract: Refrigeration systems of the ammonia-water mixtures by absorption have been widely used and referred in the literature. Usually the models found for analyses are based taking in to account data of tables and diagrams for the enthalpy as a function of the concentration. For the analysis of tables and entropy diagrams in function of the concentration of ammonia in the mixture, it has not been taken the same attention, existing lack of available data in the literature for that thermodynamic property. These systems seem to be complex as for the physiochemical parameters, becoming necessary a deeper and detailed study on the associated thermodynamics, corroborating to determine the interrelation of the entropy with other associated refrigeration properties. In this work, calculation models to improve the entropy are formulated in function of temperature, pressure and concentration of the ammonia-water mixtures S = S (T, P, x). The performance of the entropy diagrams in the liquid-vapor phase was surely aiming to aid industrial projects through energy analyses and exergetic simulation and optimization of processes related to the system of cooling by absorption. / Doutor

The way in which computers are used is important in the theory, philosophy and practice of architecture. Architects are already using computers to construct complex three dimensional geometric models of their buildings and are beginning to analyse these models using environmental and structural software, a development which raises new questions about the role of architects and engineers. This dissertation puts forward the hypothesis that architects will at times need to be actively involved in computer programming by writing or modifying software. The hypothesis is based on the assumption that the form of a building and its spatial configuration are influenced by the nature of the design process itself. If architects are to have a complete and subtle control over design and to identify their own personal aesthetic language, they must also have control over the design process including the way computer software tools are developed and used. The hypothesis is tested using the example of a ferry terminal, a building type whose function is largely dominated by passenger circulation. Even thought passengers have a very straightforward aim to reach their final destination, the rules governing the way passengers move around the building are complex and a single computer program will not be able to cover all possible aspects of such behaviour. Thus, architects must have the freedom to formulate different rules and study the effects they have on their design. This particularly applies in non-emergency situations when each individual moves inside the building according to different needs and desires. A program was written which runs in real time so that the architect can see the effect of changing the parameters that control the process. The program can be used as evaluation mechanism to study the performance of postulated design or it can be use as creative mechanism where the design may emerge out of the process in the same way that animals create paths in the woods. Either way, the general aim is to optimize the design according to criteria over which the architect, again, must have complete control.