Software engineering has been facing a crisis for several years now - there is more demand for new software than there is ability to supply. Software reuse is a potential way to tackle the problems caused by the software crisis with its promises of increased productivity and cheaper development costs. Several software reuse successes have been reported, but these have been predominantly in large, well structured companies. However, there are numerous smaller companies that could also benefit from reuse if it were made available to them. This thesis addresses these issues by implementing a reuse programme in a small company. An incremental approach to reuse introduction is adopted, following the Seven Steps to Success, and 'lightweight' processes are recommended to support the reuse programme. A prototype tool set, ReThree- C++, was developed to automate support for the reuse programme. The results of the case study are presented. The reuse programme was successful, with benefits to the company including both increased speed of production and financial gains from selling reusable components. The challenges faced are also identified. Details of the tool set giving automated support for reuse are also presented. The tool set is an approach to reuse repository control which also integrates information abstraction from C++ source code to generate class hierarchy charts and software documentation automatically. It helps developers store, retrieve, understand and use reusable components. The usefulness of the tool set is shown with an experiment and as part of the case study. The purpose of the thesis is to show that small companies can implement reuse, and that the method presented supports the introduction of a reuse programme. It concludes that although challenges were faced, great benefits can be gained by using the method with automated support for reuse in a small company.

Web applications are one of the fastest growing types of software systems today. Structurally, they are composed out of two parts: the server-side, used for data-access and business logic, and the client-side used as a user-interface. In recent years, thanks to fast, modern web browsers and advanced scripting techniques, developers are building complex interfaces, and the client-side is playing an increasingly important role. From the user's perspective, the client-side offers a number of features. A feature is an abstract notion representing a distinguishable part of the system behavior. Similar features are often used in a large number of web applications, and facilitating their reuse would offer considerable benefits. However, the client-side technology stack does not offer any widely used structured reuse method, and code responsible for a feature is usually copy-pasted to the new application. Copy-paste reuse can be complex and error prone - usually it is hard to identify exactly the code responsible for a certain feature and introduce it into the new application without errors. The primary focus of the research described in this PhD thesis is to provide methods and tools for automatizing reuse in client-side web application development. This overarching problem leads to a number of sub-problems: i) how to identify code responsible for a particular feature; ii) how to include the code that implements a feature into an already existing application without breaking neither the code of the feature nor of the application; and iii) how to automatically generate sequences of user actions that accurately capture the behavior of a feature? In order to tackle these problems we have made the following contributions: i) a client-side dependency graph that is capable of capturing dependencies that exist in client-side web applications, ii) a method capable of identifying the exact code and resources that implement a particular feature, iii) a method that can introduce code from one application into another without introducing errors, and iv) a method for generating usage scenarios that cause the manifestation of a feature. Each contribution was evaluated a suite of web applications, and the evaluations have shown that each method is capable of performing its intended purpose.

No description available.

The study reported here was aimed at optimising the microfiltration (MF) membrane process applied to water reclamation. Polypropylene hollow fibre membrane (0.2 ??m) with high pressure backwahing was mainly used in this study. To obtain secondary effluent for microfiltration a biological treatment (UASB/SBR) was applied to brewery effluent. It was identified that loading at a rate below 14 kg COD/kLd will ensure the stable performance of UASB. An initial energy balance of the system (Biological and MF) shows a plant treating brewery effluent (4000 mg/L COD) could yield a net energy of 2.5 kWh/kL (yield from methane less the plant operating energy) at an optimised MF flux. For the MF of low solids feed it was found that crossflow has no benefit and that intermittent dead end filtration is less productive than dead-end cycles. It was also that found cycle time between air backwashes is strongly dependent on the imposed flux and the maximum TMP allowed. Analysis based on energy and capital cost indicates that if energy saving is the objective the unit needs to be operated at low imposed flux. However, if capital and energy costs are combined, cost efficient operation would be at about 60 to 70 L/m2.h for TMPmax of 20 kPa or above 80 L/m2.h for TMPmax of 50 kPa. For cycles with a TMPmax of 20 kPa, the specific cake resistance was constant over the range of imposed fluxes. However, for a TMPmax of 50 kPa the specific resistance was higher and increased with imposed flux, signifying compressible cake formation. Further analysis of the TMP profiles showed that the membrane resistance increased over a number of cycles and that the increase was higher at higher flux. To fully optimise the operation, it would be necessary to include these factors. Laboratory scale studies with yeast showed many similarities with secondary effluent filtration. However, some inconsistencies were observed at lower f1uxes, which need to be confirmed by further studies. Life cycle assessment of the membrane filtration process indicated that operating at low flux (10 Llm2.h) with higher TMPmax is the environmentally sound operational strategy. The analysis highlights the fact that the environmental impacts mainly come from the membrane operation (more than 85%). When alternative energy sources are considered, the least impact operational strategy shifts towards higher flux (in the vicinity of 30 l/m2.h). In-situ electrochemical cleaning using an electrolysis process indicated better flux recovery than traditional chemical cleaning. However, repeated cycles of fouling and cleaning showed electrochemically cleaned membranes have a higher fouling tendency than the chemically cleaned membrane. Initial characterisation of membrane surface properties after cleaning could not provide conclusive evidence for the cause of rapid fouling of the electrochemically cleaned membrane.

Thesis (Ph. D. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.

Thesis (M.S. - Agronomy and Plant Genetics)--University of Arizona. / Includes bibliographical references.

Thesis (Ph. D. - Civil Engineering and Engineering Mechanics)--University of Arizona. / Includes bibliographical references.

Thesis (Ph. D. - Hydrology and Water Resources)--University of Arizona, 1989. / Includes bibliographical references (leaves 245-252).

Thesis (Ph. D. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.

Thesis (M.S.)--University of Nevada, Reno, 2006. / "August, 2006." Includes bibliographical references (leaves 67-70). Online version available on the World Wide Web.