Att arbeta med ett äldre så kallat legacy-system är en vanlig uppgift bland dagens programmerare men det saknas data om hur arbetsinsatsen är fördelad. Denna data vore användbar för att utvärdera hur kostsamt det är att vidareutveckla ett system kontra en omskrivning eller migration. För att åtgärda detta bidrar den här undersökningen med data som visar arbetsinsatsfördelningen vid migration av ett mindre legacy-system. Frågan som undersöks är ”Hur fördelas kostnaden i tid när man utvärderar och bygger om ett legacy-system?. Grunden för data i denna undersökning kommer ifrån utvecklingen av ett litet studentutvecklat system som använts på KTH och som var i stort behov av uppdatering. Det fanns mycket dokumentation om systemets krav och design, men den kod som fanns var ej användbar då den ej var dokumenterad och saknade klar struktur. Detta ledde till en omskrivning av systemet enligt de krav som tidigare formulerats. I det här projektet användes en vetenskaplig fallstudie med en kvantitativ metod för att få fram resultat. Tiden som lades ned på de moment som identifierats innan uppstart mättes och användes för att beräkna arbetsinsatsfördelningen. Resultatet av denna undersökning är en samling data som kan användas för uppskattningen av arbetsinsatsfördelningen vid omskrivningen av ett mindre legacy-system. I denna undersökning redovisas arbetsinsatsfördelningen som uppmätts under migrationen av ett legacy-system till en ny teknologi, då det existerande systemet inte betraktades som värt att uppdatera. Undersökningens slutsats är att om det finns ett bra förarbete som går att använda för att bygga om systemet så kommer majoriteten av arbetsarbetsinsatsen att läggas på implementeringen av systemet i kod. / Working with legacy-systems is a common task for programmers, and the development of these requires a great effort, but data regarding the distribution of this effort is scarce. This data would be valuable when evaluating the cost of continued development of a system compared to a rewrite or migration. To rectify this, we aim to provide a datapoint regarding the effort distribution for the migration of a small legacy-system. Our question is “How is the cost in time distributed when a legacy-system is evaluated and rebuilt?”. The data presented in this thesis comes from the development of a legacy-system developed by students at KTH. The system needed an update since it had ceased to function. There was a great amount of documentation with regards to requirement specifications and application design which could be used when redeveloping the system. The code, however, lacked any substantial documentation and structure, so it was decided early on that rewriting the system according to the existing documentation was going to be more efficient than working with the code for the current system. A scientific case study built on quantitative methods was used to collect data. To measure effort the time spent on each predefined moment was counted in minutes, and this was used to calculate the distribution of effort. The result of this thesis is a table of data and a review of the distribution of effort when working on a small legacy-system with clear requirements. The data produced in this thesis is based on the effort spent on rewriting a system that was not worth updating. The conclusion of this thesis is that most of the effort will be spent on implementing the code when a clearly defined system is rewritten from the ground up.

Water is precious, particularly in South Australia, the driest State in Australia, with over 80% of its land area receiving less than 250mm of rainfall per year. Security of water supply has always played a critical role in the economic and social development of South Australia, and will continue to do so while dependency on water from the River Murray is so high and there is competition over this from states and for different uses – municipal, irrigation, industry, and the environment. The drive towards sustainable development has evolved to attenuate overconsumption of the world’s natural resources of which water is a key element. Provision of reliable water supplies to regional South Australia has always presented challenges, given the vast distances involved and the limited number of natural water sources. Despite these, a majority of South Australians enjoy the benefit of a reliable and safe water supply, adequate waste disposal system, good community health and high standard of living. A challenge remains to determine the sustainability of current major water pipe transfer systems from remote resources to small communities. There may be scope for managing existing water supplies more effectively and further developing local water harvesting and reuse solutions to minimise the need for more significant infrastructure investment. This study investigates the challenges and opportunities for extending development of non-potable (secondary) water supply schemes in South Australian towns. These schemes will conserve the State’s freshwater resources. The primary focus of this study is harnessing stormwater runoff and treated effluent generated by normal township development to supplement higher quality public water for uses such as irrigation of public areas and sporting fields in country areas. Water harvesting and reuse is not likely to occur due to some technological breakthrough but through application of known technology and the adoption of water conscious ethics by society. However, it is a sensible reality for the South Australian climate, particularly when coupled with appropriate conservation and suitable landscaping practices. Thus, the major theme of this study is information sharing since if people are familiar with and understand the concepts then more communities may be encouraged to develop their resources. Water reuse has proven to be a beneficial strategy for addressing stormwater runoff and wastewater disposal problems and alleviating localised water supply problems for several South Australian towns and communities. The existing projects demonstrate both the strong community-based and innovative approach to water resources management in this state. They are inherently simple in form, and can often be assembled with readily available materials by people with a basic understanding of plumbing and construction skills (locally available). The potential for localised water harvesting and reuse in South Australian towns is generally limited to single purpose communal non-potable systems. Further, it is likely to only be sustainable in rural communities willing to make a commitment to its long term, proper operation and maintenance, or they could endanger public health. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1283773 / Thesis (M.Eng.Sc.) - University of Adelaide, School of Civil and Environmental Engineering, 2007

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