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I den här rapporten utreds möjligheten att fräsa laxkilar av konstruktionsstål, enkomponent som ingår i de vågkraftgeneratorer som utvecklas vid Uppsala universitet,genom att använda en industrirobot. Denna användning av robotar inom bearbetningskiljer sig från den konventionella genom att roboten här genom helabearbetningsmomentet håller det bearbetade stycket. Den vanliga användningen avrobotar inom bearbetning är att roboten används för att plocka stycket i och ur enbearbetningsmaskin. Genom att istället låta roboten hålla stycket genom helabearbetningen kan dess flexibilitet utnyttjas.Rapporten presenterar resultat av den använda robotens uppmätta egenskaper samtpraktiska tester av fräsning. Ett antal laxkilar har tillverkats med metoden och utifrånanalyser av dessa har en kvalitetsmässigt och produktivitetsmässigt utvärdering avmetoden gjorts.Ett robotverktyg för att hålla ämnet som ska bearbetas har designats och en prototyp avverktyget har tillverkats. I rapporten presenteras även ett förslag på en komplettrobotcell för bearbetningen.Resultatet av testerna visar att det är möjligt att fräsa laxkilar med presenterad metod.Ytjämnheten är sämre, måttavvikelserna är större och tillverkningstider är högre än vidkonventionell fräsning. Detta resultat är väntat då roboten är mindre stabil än enbearbetningsmaskin, vilket innebär att den är sämre på att motstå de vibrationer somskärkrafter vid fräsning ger upphov till. Metoden är därför lämplig för tillämpningar därkraven på dessa egenskaper inte är så höga.Ytterligare tester krävs dock för att undersöka metodens repeterbarhet och slitage påutrustningen. Även robotverktyget behöver verifieras i ytterligare tester.Nyckelord. Industrirobot,

Testing plays an important role in the wireless protocol stack development. In order to free the testers out of the shielded chamber, allow both the developers and the testers to use the test systems remotely and maximize the expensive test system usage. An automated test framework is highly demanded. In this thesis, the design of the automated test framework is introduced. There are four main components in the test framework. They are the front end, scheduler, test engine and data storage. The architecture and the protocol among these components are described. Further, the evaluation of the scheduler is conducted based on the queueing theory. Based on the simulation result, a good scheduling algorithm is proposed. Compared with the original scheduling algorithm, the new algorithm improves the performance of the low priority users significantly when the test systems are limited. Moreover, the detail design of the test engine is presented. With the control of the intelligent test engine, the automated test framework has the capability to launch the test cases automatically, catch the commands sent by the test system and manipulate the SUT (System Under Test) without human’s interrupt. It fulfills the objective of automation. The automated test framework has been deployed and is working well.

South Africa is experiencing a serious electricity supply problem. This problem is expected to persist until at least 2012. During the winter of 2006 load shedding and electricity supply-cuts started occurring in the Western Cape. These spread to the rest of the country during the summer of 2007. By January 2008 daily load shedding was a common occurrence across South Africa. In the 1990s the Department of Minerals and Energy (DME), the National Energy Regulator of South Africa (NERSA) and Eskom started a national demand side management (DSM) programme with the help of energy services companies (ESCOs). The aim is to reduce demand peaks and to promote the efficient use of electricity. These projects can be implemented much faster than building new power stations and are also more cost-effective. In 2008 an accelerated DSM program was launched to address the electricity shortage in South Africa. Unfortunately, South African DSM projects experience the same sustainability problems as their counterparts overseas. These projects have been shown to be unsustainable over the five year projected life-span. There are various reasons for this, including client mismanagement and maintenance problems. An automated and rapid feedback system was identified as the best solution to address this problem. If plant personnel could be informed as soon as a DSM project's performance starts to decline, they would be able to respond much faster to rectify the problem. Reporting on DSM performance is difficult to achieve as these reports and the processing of measured data are time-consuming and presently no system exists to automate the process. A new feedback solution was developed to fully automate the process of data gathering, processing and reporting. The implemented solution reduced the number of man-hours spent by ESCOs' project engineers dramatically. In addition, project performance increased by 13% and showed an increase in over-performance of 12.8%, while financial savings for clients improved by an average of 12%. The feedback solution also provides the client with an accurate maintenance reporting system. This system can be implemented on all DSM projects, maximising Eskom's DSM investment. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.

South Africa is experiencing a serious electricity supply problem. This problem is expected to persist until at least 2012. During the winter of 2006 load shedding and electricity supply-cuts started occurring in the Western Cape. These spread to the rest of the country during the summer of 2007. By January 2008 daily load shedding was a common occurrence across South Africa. In the 1990s the Department of Minerals and Energy (DME), the National Energy Regulator of South Africa (NERSA) and Eskom started a national demand side management (DSM) programme with the help of energy services companies (ESCOs). The aim is to reduce demand peaks and to promote the efficient use of electricity. These projects can be implemented much faster than building new power stations and are also more cost-effective. In 2008 an accelerated DSM program was launched to address the electricity shortage in South Africa. Unfortunately, South African DSM projects experience the same sustainability problems as their counterparts overseas. These projects have been shown to be unsustainable over the five year projected life-span. There are various reasons for this, including client mismanagement and maintenance problems. An automated and rapid feedback system was identified as the best solution to address this problem. If plant personnel could be informed as soon as a DSM project's performance starts to decline, they would be able to respond much faster to rectify the problem. Reporting on DSM performance is difficult to achieve as these reports and the processing of measured data are time-consuming and presently no system exists to automate the process. A new feedback solution was developed to fully automate the process of data gathering, processing and reporting. The implemented solution reduced the number of man-hours spent by ESCOs' project engineers dramatically. In addition, project performance increased by 13% and showed an increase in over-performance of 12.8%, while financial savings for clients improved by an average of 12%. The feedback solution also provides the client with an accurate maintenance reporting system. This system can be implemented on all DSM projects, maximising Eskom's DSM investment. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.

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Text categorization (TC) is the task of automatically categorizing textual digital documents into pre-set categories by analyzing their contents. The purpose of this study is to develop an effective TC model to resolve the difficulty of automatic classification. In this study, two primary goals are intended. First, a Hidden Markov Model (HAM is proposed as a relatively new method for text categorization. HMM has been applied to a wide range of applications in text processing such as text segmentation and event tracking, information retrieval, and information extraction. Few, however, have applied HMM to TC. Second, the Library of Congress Classification (LCC) is adopted as a classification scheme for the HMM-based TC model for categorizing digital documents. LCC has been used only in a handful of experiments for the purpose of automatic classification. In the proposed framework, a general prototype for an HMM-based TC model is designed, and an experimental model based on the prototype is implemented so as to categorize digitalized documents into LCC. A sample of abstracts from the ProQuest Digital Dissertations database is used for the test-base. Dissertation abstracts, which are pre-classified by professional librarians, form an ideal test-base for evaluating the proposed model of automatic TC. For comparative purposes, a Naive Bayesian model, which has been extensively used in TC applications, is also implemented. Our experimental results show that the performance of our model surpasses that of the Naive Bayesian model as measured by comparing the automatic classification of abstracts to the manual classification performed by professionals.

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