Evaluation of the determinism of the actuator sensor interface (ASI) on programmable logic controllers (PLC), personal computers (PC) and real-time operating systems (RTOS)

The purpose of this study was to evaluate the determinism of the AS-lnterface network and the 3 main families of control systems, which may use it, namely PLC, PC and RTOS. During the course of this study the PROFIBUS and Ethernet field level networks were also considered in order to ensure that they would not introduce unacceptable latencies into the overall control system. This research demonstrated that an incorrectly configured Ethernet network introduces unacceptable variable duration latencies into the control system, thus care must be exercised if the determinism of a control system is not to be compromised. This study introduces a new concept of using statistics and process capability metrics in the form of CPk values, to specify how suitable a control system is for a given control task. The PLC systems, which were tested, demonstrated extremely deterministic responses, but when a large number of iterations were introduced in the user program, the mean control system latency was much too great for an AS-I network. Thus the PLC was found to be unsuitable for an AS-I network if a large, complex user program Is required. The PC systems, which were tested were non-deterministic and had latencies of variable duration. These latencies became extremely exaggerated when a graphing ActiveX was included in the control application. These PC systems also exhibited a non-normal frequency distribution of control system latencies, and as such are unsuitable for implementation with an AS-I network. The RTOS system, which was tested, overcame the problems identified with the PLC systems and produced an extremely deterministic response, even when a large number of iterations were introduced in the user program. The RTOS system, which was tested, is capable of providing a suitable deterministic control system response, even when an extremely large, complex user program is required.

Applications of stochastic analysis in finance and statistical inference

First: A continuous-time version of Kyle's model (Kyle 1985), known as the Back's model (Back 1992), of asset pricing with asymmetric information, is studied. A larger class of price processes and of noise traders' processes are studied. The price process, as in Kyle's model, is allowed to depend on the path of the market order. The process of the noise traders' is an inhomogeneous Lévy process. Solutions are found by the Hamilton-Jacobi-Bellman equations. With the insider being risk-neutral, the price pressure is constant, and there is no equilibirium in the presence of jumps. If the insider is risk-averse, there is no equilibirium in the presence of either jumps or drifts. Also, it is analised when the release time is unknown. A general relation is established between the problem of finding an equilibrium and of enlargement of filtrations. Random announcement time is random is also considered. In such a case the market is not fully efficient and there exists equilibrium if the sensitivity of prices with respect to the global demand is time decreasing according with the distribution of the random time. Second: Power variations. it is considered, the asymptotic behavior of the power variation of processes of the form _integral_0^t u(s-)dS(s), where S_ is an alpha-stable process with index of stability 0&alpha&2 and the integral is an Itô integral. Stable convergence of corresponding fluctuations is established. These results provide statistical tools to infer the process u from discrete observations. Third: A bond market is studied where short rates r(t) evolve as an integral of g(t-s)sigma(s) with respect to W(ds), where g and sigma are deterministic and W is the stochastic Wiener measure. Processes of this type are particular cases of ambit processes. These processes are in general not of the semimartingale kind.

Field Evaluation of Quality Management Concrete, MLR-97-3, 1998

Quality management concrete allows the contractor to develop the mix design for the portland cement concrete. This research was initiated to gain knowledge about contractor mix designs. An experiment was done to determine the variation in cylinders, beams, and cores that could be used to test the strength of the contractor's mix. In addition, the contractor's cylinder strengths and gradations were analyzed for statistical stability and process capability. This research supports the following conclusions: (1) The mold type used to cast the concrete cylinders had an effect on the compressive strength of the concrete. The 4.5-in. by 9-in. (11.43-cm by 22.86-cm) cylinders had lower strength at a 95% confidence interval than the 4-in. by 8-in. (10.16-cm by 20.32-cm) and 6-in. by 12-in. (15.24-cm by 30.48-cm) cylinders. (2) The low vibration consolidation effort had the lowest strength of the three consolidation efforts. In particular, an interaction occurred between the low vibration effort and the 4.5-in. by 9-in. (11.43-cm by 22.86-cm) mold. This interaction produced very low compressive strengths when compared with the other consolidation efforts. (3) A correlation of 0.64 R-squared was found between the 28 day cylinder and 28 day compressive strengths. (4) The compressive strength results of the process control testing were not in statistical control. The aggregate gradations were mostly in statistical control. The gradation process was capable of meeting specification requirements. However, many of the sieves were off target. (5) The fineness modulus of the aggregate gradations did not correlate well with the strength of the concrete. However, this is not surprising considering that the gradation tests and the strength tests did not represent the same material. In addition, the concrete still has many other variables that will affect its strength that were not controlled.

Vaatimustenkäsittely ohjelmistopalveluyrityksessä

Vaatimustenkäsittely on erittäin tärkeä osa-alue tehtäessä uusia ohjelmistoja. Vaatimustenkäsittely ei ole vain vaatimusmääritettydokumentin kokoamista ohjelmistoprojektin alussa vaan siihen sisältyy vaatimusten määrittely, hallinta ja todentaminen koko ohjelmiston elinkaaren ajan. Ohjelmistopalveluyrityksessä vaatimustenkäsittelyn merkitys korostuu entisestään ja tällaisella yrityksellä on oltava toimiva vaatimustenkäsittelyprosessi. Tässä työssä esitellään vaatimustenkäsittelyn teoriaa, prosesseihin liittyvää laadunvalvontaa sekä prosessien arviointi ja -kehittämismalleja. Työssä tarkastellaan kahden erityyppisen ohjelmistopalveluyrityksen vaatimustenkäsittelyä ja esitetään havaintoja prosessimalleista. Työn tuloksena esitetään johtopäätöksiä vaatimustenkäsittelystä ja siihen liittyvistä prosesseista sekä laadunvalvonnasta.

Multifactor Performance Study on Complex Systems for the Benefit of Management

The primary objective is to identify the critical factors that have a natural impact on the performance measurement system. It is important to make correct decisions related to measurement systems, which are based on the complex business environment. The performance measurement system is combined with a very complex non-linear factor. The Six Sigma methodology is seen as one potential approach at every organisational level. It will be linked to the performance and financial measurement as well as to the analytical thinking on which the viewpoint of management depends. The complex systems are connected to the customer relationship study. As the primary throughput can be seen in a new well-defined performance measurement structure that will also be facilitated as will an analytical multifactor system. These critical factors should also be seen as a business innovation opportunity at the same time. This master's thesis has been divided into two different theoretical parts. The empirical part consists of both action-oriented and constructive research approaches with an empirical case study. The secondary objective is to seek a competitive advantage factor with a new analytical tool and the Six Sigma thinking. Process and product capabilities will be linked to the contribution of complex system. These critical barriers will be identified by the performance measuring system. The secondary throughput can be recognised as the product and the process cost efficiencies which throughputs are achieved with an advantage of management. The performance measurement potential is related to the different productivity analysis. Productivity can be seen as one essential part of the competitive advantage factor.

Surface Modification of Ceramics

Ceramics are widely used in industrial applications due to their advantageous thermal and mechanical stability. Corrosion of ceramics is a great problem resulting in significant costs. Coating is one method of reducing adversities of corrosion. There are several different thin film deposition processes available such as sol-gel, Physical and Chemical Vapour Deposition (PVD and CVD). One of the CVD processes, called Atomic Layer Deposition (ALD) stands out for its excellent controllability, accuracy and wide process capability. The most commonly mentioned disadvantage of this method is its slowness which is partly compensated by its capability of processing large areas at once. Several factors affect the ALD process. Such factors include temperature, the grade of precursors, pulse-purge times and flux of precursors as well as the substrate used. Wrongly chosen process factors may cause loss of self-limiting growth and thus, non-uniformities in the deposited film. Porous substrates require longer pulse times than flat surfaces. The goal of this thesis was to examine the effects of ALD films on surface properties of a porous ceramic material. The analyses applied were for permeability, bubble point pressure and isoelectric point. In addition, effects of the films on corrosion resistance of the substrate in aqueous environment were investigated. After being exposured to different corrosive media the ceramics and liquid samples collected were analysed both mechanically and chemically. Visual and contentual differences between the exposed and coated ceramics versus the untreated and uncoated ones were analysed by scanning electron microscope. Two ALD film materials, dialuminium trioxide and titanium dioxide were deposited on the ceramic substrate using different pulse times. The results of both film materials indicated that surface properties of the ceramic material can be modified to some extent by the ALD method. The effect of the titanium oxide film on the corrosion resistance of the ceramic samples was observed to be fairly small regardless of the pulse time.

Teleskooppipuomin valmistuksen kehittäminen

KESLA 2110T -autonosturin siirtopuomin teleskooppimainen rakenne koostuu kolmesta sisäkkäin menevästä puomista. Näiden puomien muodonmuutokset ja mittavaihtelut ovat kriittisiä seikkoja siirtopuomin kokoonpantavuuden kannalta. Liian suuret muodonmuutokset ja mittavaihtelut aiheuttavat ylimääräistä työtä siirtopuomien kokoonpanossa, mikä lisää tuotteen läpimenoaikaa ja valmistuskustannuksia. Työssä pyrittiin selvittämään valmistusprosessin kriittisimmät osat kokoonpantavuuden kannalta sekä varmistamaan niiden vaikutus mittauksin. Valmistusprosessin ongelmakohtia selvitettiin ensin haastattelemalla tuotannon työntekijöitä ja toimihenkilöitä. Saatujen tuloksien perusteella suunniteltiin tarkoituksenmukaiset mittausjärjestelyt, joilla valmistusprosessin ongelmakohdat voidaan todeta. Mittaukset suoritettiin kahdelle viiden siirtopuomin koesarjalle ja samalla kehitettiin valmistusprosessia. Puomien mittauksissa keskityttiin kokoonpanon kannalta kriittisiin mittoihin. Mittatuloksia arvioidaan toleranssien, standardien ja prosessien suorituskyvyn parametrien avulla. Työssä selvitettiin myös rullamuovauksen soveltuvuutta puomien valmistusmenetelmäksi sekä välyksen vaikutusta kokoonpantavuuden kehittämiseksi. Mittauksissa havaittiin mittavirheiden kertautuvan valmistusprosessin varrella. Kokoonpantavuuden kannalta kriittisimmät virheet ovat puomien alakotelon V-pohjan toislaitaisuus sekä puomien kieroutuminen hitsausvaiheessa. Puomien korkeus- tai leveysvaihteluilla ei ole suurta merkitystä, sillä niitä voidaan kompensoida liukupaloja säätämällä.

Índice de capacidade do processo na avaliação da irrigação por aspersão

Analisar a qualidade da irrigação, além de avaliar seu bom funcionamento, é uma forma de verificar a viabilidade de sua implantação e operação. Como a uniformidade de distribuição é um dos parâmetros mais utilizados para essa avaliação, este trabalho objetivou utilizar técnicas de engenharia de qualidade, usando o índice de capacidade do processo (Cpl) para avaliar a uniformidade de distribuição de água em um sistema de irrigação por aspersão convencional. Os ensaios foram conduzidos no Núcleo Experimental de Engenharia Agrícola, UNIOESTE, com dois aspersores modelo Super10, marca NAANDAN, espaçados 9 m entre si, durante 25 irrigações de 1 h cada. Os dados climáticos foram coletados a cada 10 min, por uma estação meteorológica sem fio. Encontraram-se um CUC médio de 79,72% e velocidade do vento média de 1,85 m s-1. Foram aplicados os testes de controle de qualidade, elaborando os gráficos de controle de Shewhart e calculado o índice de capacidade do processo (Cpl), sendo que os resultados obtidos permitem afirmar que a utilização do índice de capacidade do processo torna-se uma ferramenta poderosa para classificar sistemas de irrigação em função de sua uniformidade de distribuição.

Variabilidade espacial e diagnóstico da qualidade do processo em semeadura de amendoim

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise da variabilidade do processo de filtração em filtros de tambor rotativo contínuo a vácuo para lodo de caldo de cana de açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aplicação do lean six sigma na linha de produção de turbinas industriais a vapor

This work evaluates the implementation of Lean Six Sigma into the Steam Turbine’s Blades Manufacturing Process, aiming to improve productivity, quality and operational efficiency. Therefore, several tools have been applied, such as VSM, Spaghetti Diagram, Ishikawa, Pareto, DMAIC, Benchmarking and Control Charts, seeking to propose process improvements, as well as Quality Indicators creation. It was obtained a significant waste reduction throughout the process, achieving a lead time reduction of 42% and 83,41% in transport. Also, were introduced the Lean Thinking concepts, such as pull production and Continuous material flow. At the same time, it was possible to calculate the process capability and the sigma level, evaluating and proposing some improvements

Estudo de caso de controle estatístico de processo: levantamento estatístico de defeitos em molduras

This graduate work approaches the study of Statistical Process Control - SPC, in a stage production of an industrial frame, aiming to use the tool of statistical process control (SPC) to assess the process capability. Where the process needs improvement as well not meet the specifications. Assessing the needs that the company needs to improve quality management, and the difficulties they present during the implementation of the CEP. The present study is to use the method of case study. The results are presented through study of the level of defects using Pareto diagrams and control chart by - (p) fraction defective, and checking the capacity and stability of the process using control charts and histograms XbarraR. The process demonstrated the need for improvements in process and quality management. At the end of the work are presented suggestions for improving the quality system of the company

Estudo de caso de controle estatístico de processo: levantamento da variação de espessura de tábuas de pinus

This graduate work approaches the study of Statistical Process Control - SPC, in a stage production of an industrial frame, aiming to use the tool of statistical process control (SPC) to assess the process capability. Where the process needs improvement as well not meet the specifications. Assessing the needs that the company needs to improve quality management, and the difficulties they present during the implementation of the CEP. The present study is to use the method of case study. The results are presented through study, and checking the capacity and stability of the process using control charts XbarraR. The process demonstrated the need for improvements in process and quality management. At the end of the work are presented suggestions for improving the quality system of the company

Multi-criteria analysis in the strategic environmental assessment of the sugar and alcohol sector

The Strategic Environmental Assessment (SEA) of the sugar and alcohol sector guides a territorial and sectoral planning that benefits most of the local society and supports this economic activity in all its stages. In this way, the present work aims to determine an index of aggregation of the indicators generated in the baseline of the SEA process, called Index of Sustainability of Expansion of the Sugar and Alcohol Sector (IScana). For this, it was used the normalization of the indicators of each city by the fuzzy logic and attribution of weights by the Analytic Hierarchy Process (AHP). Then, the IScana values had been spatialized in the region of 'Grande Dourados'-Mato Grosso do Sul State. The northern portion concentrated the highest values of IScana, 0.48 and 0.55, referring to the cities of Nova Alvorada do Sul and Rio Brilhante, while, in the central portion, the city of Dourados presented the lowest value, 0.10. The selection of the set of indicators forming the IScana, and their relative importance, was satisfactory for the application of fuzzy logic and AHP techniques. The IScana index supplies objective information regarding the diagnosis of the region for the application of SEA.