The technology that has emerged in commercial products requires rigorous analytical tools for effective design of such motors. A finite element analytical model was developed to examine the excitation of flexural plate wave travelling in a rotary piezoelectric ally actuated motor. The model uses annular finite elements that are applied to predict the excitation frequency and modal response of an annular stator. This model is being developed to enable the design of efficient ultrasonic motors and it incorporates the details of the stator which include the teeth, piezo-ceramic, stator geometry, etc.

Šiame darbe buvo išanalizuota keletas paieškos sistemų, bei įvardinti jų privalumai bei trūkumai. Palygintos sistemos kūrimo technologijos. Tai įvertinus buvo sukurta informacijos paieškos sistema elektroninėje bibliotekoje (eLABa). Jos pagrindinis privalumas yra tai, kad paieška vykdoma ne tik tarp dokumento metaduomenų (aprašo), bet ir dokumento tekste. Eksperimentiškai buvo nustatytas galimas paieškos vykdymo optimizavimas. / This system is invented to help people search for the e. documents in FEDORA repository. The system has following features: indexing of Fedora FOXML records, including the text contents of data streams and search in the index. There is possibility to registered users to save results in the history page, and to do repeated search if you want. Also you can go directly to e. document after you have made search.

Magistro baigiamojo darbo teorinėje dalyje analizuojami įvairūs virpesių lygio mažinimo būdai bei schemos laivuose. Aprašoma virpesių klasifikacija, pagrindiniai virpesių žadintojai laive, virpesių skaičiavimo būdai. Eksperimentinėje dalyje pateikiama kelto „Optima Seaways“ siurblio virpesių matavimo metodika. Nagrinėjami reiso Klaipėda-Karlshamnas-Klaipėda metu atliktų matavimų rezultatai bei nustatomos tiriamo siurblio padidinto virpesių lygio priežastys. Paskutinėje darbo dalyje pateikiamas racionalus sprendimas, reikalaujantis minimalių lėšų ir laiko sanaudų, tiriamo siurblio virpesių lygio sumažinimui. / The theoretical part of the Master’s thesis analyzes various vibration reduction systems and schemes in ships. Classification of vibrations on board, main vibration sources and vibration calculations are presented. The experimental part presents methodic for vibration measuring of ferry “Optima Seaways” pump. Vibration data, received during passage Klaipėda- Karlshamn- Klaipėda, is analyzed and reason of high pump vibration level is identified. Last part of thesis presents rational solution, with minimal cost and time expenses, for reduction of pump vibration level.

Linear induction motors are applied in equipments with different requirements set up to the controlled motion parameters. Investigation of motoring and breaking modes remains the relevant problem nowadays. The scientific novelty is based on analysis of non-symmetrical operation modes of linear induction motor at supplying it by a voltage source, developing a generalized model of motoring and breaking dynamic modes and analyzing influence of linear motor windings connection way and control parameters on dynamic breaking characteristics. The coordinate transformations of linear induction motors dynamic models, based on rotational motor with assumptions valid for low speed motor and multi-pole motor, are considered. Mathematical and computer models to investigate symmetrical dynamic modes of linear induction drives are presented. Generalized model to investigate non-symmetrical dynamics modes is elaborated. The results of simulation are presented by dependences on the main variables in the time domain, and dependences on both constructional and control parameters that give possibility to optimize constructional parameters of motors.

Linear induction motors are applied in equipments with different requirements set up to the controlled motion parameters. Investigation of motoring and breaking modes remains the relevant problem nowadays. The scientific novelty is based on analysis of non-symmetrical operation modes of linear induction motor at supplying it by a voltage source, developing a generalized model of motoring and breaking dynamic modes and analyzing influence of linear motor windings connection way and control parameters on dynamic breaking characteristics. The coordinate transformations of linear induction motors dynamic models, based on rotational motor with assumptions valid for low speed motor and multi-pole motor, are considered. Mathematical and computer models to investigate symmetrical dynamic modes of linear induction drives are presented. Generalized model to investigate non-symmetrical dynamics modes is elaborated. The results of simulation are presented by dependences on the main variables in the time domain, and dependences on both constructional and control parameters that give possibility to optimize constructional parameters of motors.