Lomborg, Vanhanen ja Intelligent Design - kommentti Matti Kamppiselle

Kommentti Matti Kamppisen kirjoitukseen TT -lehdessä 1/2005

Utilisation of Statistics in Intelligent Web Applications

Web-portaalien aiheenmukaista luokittelua voidaan hyödyntää tunnistamaan käyttäjän kiinnostuksen kohteet keräämällä tilastotietoa hänen selaustottumuksistaan eri kategorioissa. Tämä diplomityö käsittelee web-sovelluksien osa-alueita, joissa kerättyä tilastotietoa voidaan hyödyntää personalisoinnissa. Yleisperiaatteet sisällön personalisoinnista, Internet-mainostamisesta ja tiedonhausta selitetään matemaattisia malleja käyttäen. Lisäksi työssä kuvaillaan yleisluontoiset ominaisuudet web-portaaleista sekä tilastotiedon keräämiseen liittyvät seikat.

Development of Paperboard Forming Tools with a Focus on Intelligent Manufacturing

Tämä diplomityö käsittelee kartonginmuovaukseen käytettävien puristintyökalujen kehittämistä. Työntavoitteina oli kehittää työkalutekniikan suunnittelua ja valmistusta edullisemmaksi, nopeammaksi ja työkaluja toiminnoiltaan tehokkaammiksi. Työn tuli sisältää myös ohjeet työkalujen suunnittelemiseksi ja valmistamiseksi jatkoa ajatellen. Työn aikana selvitettiin mahdollisia työkalurakennevaihtoehtoja, valmistusmateriaaleja sekä niiden käsittelymenetelmiä ja lastuamista sekä sen tarjoamia mahdollisuuksia valmistusmenetelmänä. Työkalupari suunniteltiin modulaariseksi siten, että uusia työkaluja varten vain osa komponenteista täytyy valmistaa uudelleen, samalla työkalun osien lukumäärää pienennettiin merkittävästi. Valmistusmateriaaliksi valittiin hyvin lastuttava työkaluteräs ja sen koneistaminen tapahtui vaakakaraisessa koneistuskeskuksessa. Työn loppuvaiheessa työkalukokonaisuudelle tehtiin kustannuslaskelma jaoteltuna eri työvaiheille sekä komponenteittain. Työkalu asennettiin puristimeen ja sille suoritettiin käyttötestaus. Työn aikana karttuneen kokemuksen sekä koekäytön perusteella tehtiin jatkokehitysehdotuksia.

Data-parallel computation in parallel and distributed environments

The past few decades have seen a considerable increase in the number of parallel and distributed systems. With the development of more complex applications, the need for more powerful systems has emerged and various parallel and distributed environments have been designed and implemented. Each of the environments, including hardware and software, has unique strengths and weaknesses. There is no single parallel environment that can be identified as the best environment for all applications with respect to hardware and software properties. The main goal of this thesis is to provide a novel way of performing data-parallel computation in parallel and distributed environments by utilizing the best characteristics of difference aspects of parallel computing. For the purpose of this thesis, three aspects of parallel computing were identified and studied. First, three parallel environments (shared memory, distributed memory, and a network of workstations) are evaluated to quantify theirsuitability for different parallel applications. Due to the parallel and distributed nature of the environments, networks connecting the processors in these environments were investigated with respect to their performance characteristics. Second, scheduling algorithms are studied in order to make them more efficient and effective. A concept of application-specific information scheduling is introduced. The application- specific information is data about the workload extractedfrom an application, which is provided to a scheduling algorithm. Three scheduling algorithms are enhanced to utilize the application-specific information to further refine their scheduling properties. A more accurate description of the workload is especially important in cases where the workunits are heterogeneous and the parallel environment is heterogeneous and/or non-dedicated. The results obtained show that the additional information regarding the workload has a positive impact on the performance of applications. Third, a programming paradigm for networks of symmetric multiprocessor (SMP) workstations is introduced. The MPIT programming paradigm incorporates the Message Passing Interface (MPI) with threads to provide a methodology to write parallel applications that efficiently utilize the available resources and minimize the overhead. The MPIT allows for communication and computation to overlap by deploying a dedicated thread for communication. Furthermore, the programming paradigm implements an application-specific scheduling algorithm. The scheduling algorithm is executed by the communication thread. Thus, the scheduling does not affect the execution of the parallel application. Performance results achieved from the MPIT show that considerable improvements over conventional MPI applications are achieved.

Electromagnetic Design of a Solid Steel Rotor Motor for Demanding Operation Environments

The solid-rotor induction motor provides a mechanically and thermally reliable solution for demanding environments where other rotor solutions are prohibited or questionable. Solid rotors, which are manufactured of single pieces of ferromagnetic material, are commonly used in motors in which the rotationspeeds exceed substantially the conventional speeds of laminated rotors with squirrel-cage. During the operation of a solid-rotor electrical machine, the rotor core forms a conductor for both the magnetic flux and the electrical current. This causes an increase in the rotor resistance and rotor leakage inductance, which essentially decreases the power factor and the efficiency of the machine. The electromagnetic problems related to the solid-rotor induction motor are mostly associated with the low performance of the rotor. Therefore, the main emphasis in this thesis is put on the solid steel rotor designs. The rotor designs studied in thisthesis are based on the fact that the rotor construction should be extremely robust and reliable to withstand the high mechanical stresses caused by the rotational velocity of the rotor. In addition, the demanding operation environment sets requirements for the applied materials because of the high temperatures and oxidizing acids, which may be present in the cooling fluid. Therefore, the solid rotors analyzed in this thesis are made of a single piece of ferromagnetic material without any additional parts, such as copper end-rings or a squirrel-cage. A pure solid rotor construction is rigid and able to keep its balance over a large speed range. It also may tolerate other environmental stresses such as corroding substances or abrasive particles. In this thesis, the main target is to improve the performance of an induction motor equipped with a solid steel rotor by traditional methods: by axial slitting of the rotor, by selecting a proper rotor core material and by coating the rotor with a high-resistive stainless ferromagnetic material. In the solid steel rotor calculation, the rotor end-effects have a significant effect on the rotor characteristics. Thus, the emphasis is also put on the comparison of different rotor endfactors. In addition, a corrective slip-dependent end-factor is proposed. The rotor designs covered in this thesis are the smooth solid rotor, the axially slitted solid rotor and the slitted rotor having a uniform ferromagnetic coating cylinder. The thesis aims at design rules for multi-megawatt machines. Typically, mega-watt-size solidrotor machines find their applications mainly in the field of electric-motor-gas-compression systems, in steam-turbine applications, and in various types of largepower pump applications, where high operational speeds are required. In this thesis, a 120 kW, 10 000 rpm solid-rotor induction motor is usedas a small-scale model for such megawatt-range solid-rotor machines. The performance of the 120 kW solid-rotor induction motors is determined by experimental measurements and finite element calculations.

Artificially Intelligent and Adaptive Methods for Prediction and Analysis of Superheater Fireside Corrosion in Fluidized Bed Boilers

Superheater corrosion causes vast annual losses for the power companies. With a reliable corrosion prediction method, the plants can be designed accordingly, and knowledge of fuel selection and determination of process conditions may be utilized to minimize superheater corrosion. Growing interest to use recycled fuels creates additional demands for the prediction of corrosion potential. Models depending on corrosion theories will fail, if relations between the inputs and the output are poorly known. A prediction model based on fuzzy logic and an artificial neural network is able to improve its performance as the amount of data increases. The corrosion rate of a superheater material can most reliably be detected with a test done in a test combustor or in a commercial boiler. The steel samples can be located in a special, temperature-controlled probe, and exposed to the corrosive environment for a desired time. These tests give information about the average corrosion potential in that environment. Samples may also be cut from superheaters during shutdowns. The analysis ofsamples taken from probes or superheaters after exposure to corrosive environment is a demanding task: if the corrosive contaminants can be reliably analyzed, the corrosion chemistry can be determined, and an estimate of the material lifetime can be given. In cases where the reason for corrosion is not clear, the determination of the corrosion chemistry and the lifetime estimation is more demanding. In order to provide a laboratory tool for the analysis and prediction, a newapproach was chosen. During this study, the following tools were generated: · Amodel for the prediction of superheater fireside corrosion, based on fuzzy logic and an artificial neural network, build upon a corrosion database developed offuel and bed material analyses, and measured corrosion data. The developed model predicts superheater corrosion with high accuracy at the early stages of a project. · An adaptive corrosion analysis tool based on image analysis, constructedas an expert system. This system utilizes implementation of user-defined algorithms, which allows the development of an artificially intelligent system for thetask. According to the results of the analyses, several new rules were developed for the determination of the degree and type of corrosion. By combining these two tools, a user-friendly expert system for the prediction and analyses of superheater fireside corrosion was developed. This tool may also be used for the minimization of corrosion risks by the design of fluidized bed boilers.

Intelligent Internet Data Searching

In this thesis author approaches the problem of automated text classification, which is one of basic tasks for building Intelligent Internet Search Agent. The work discusses various approaches to solving sub-problems of automated text classification, such as feature extraction and machine learning on text sources. Author also describes her own multiword approach to feature extraction and pres-ents the results of testing this approach using linear discriminant analysis based classifier, and classifier combining unsupervised learning for etalon extraction with supervised learning using common backpropagation algorithm for multilevel perceptron.

Load and Performance Testing of Web Applications on Service Based Environments

Suorituskyky- ja kuormitustestien tekeminen sovelluksille on erittäin tärkeä osa tuotantoprosessia nykypäivänä. Myös Web-sovelluksia testataan yhä enemmän. Tarve suorituskyky- ja kuormitustestien tekemiselle on selvä. Testattavan ympäristön tämänhetkinen, mutta myös tulevaisuuden toimivuus taataan oikein tehdyillä testeillä ja niitä seuraavilla korjaustoimenpiteillä. Suurten käyttäjämäärien testaaminen manuaalisesti on kuitenkin hyvin vaikeaa. Sirpaleisen ympäristön, kuten palveluihin perustuvien Web-sovellusympäristöjen testaaminen on haaste. Tämän työn aiheena on arvioida työkaluja ja menetelmiä, joilla raskaita teollisia Web-sovelluksia voidaan testata. Tavoitteena on löytää testausmenetelmiä, joilla voidaan luotettavasti simuloida suuria käyttäjämääriä. Tavoitteena on myös arvioida erilaisten yhteyksien ja protokollien vaikutusta Web-sovelluksen suorituskykyyn.