Yra daugybė įvairiausių tipų mokslinių tiriamųjų darbų, vienas iš jų būtų magistro baigiamasis darbas. Šio darbo metu magistrantams reikia atlikti įvairius tyrimus, visapusiškai išnagrinėti savo pasirinktą temą, pasiūlyti problemos sprendimą, atlikti eksperimentą, kurio metu bus nagrinėjamas siūlomo sprendimo efektyvumas. Visus šių tyrimų rezultatus magistrantams reikia aprašyti. Magistro baigiamojo darbo aprašo rengimas studentams yra vienas iš sudėtingesnių uždavinių. Kaip ir visiems moksliniams tiriamiesiems darbams, jiems keliami tam tikri specifiniai reikalavimai. Daugelis studentų su tokio pobūdžio darbu susiduria pirmą kartą. Jiems tenka spręsti ne tik pasirinktos tyrimo srities problemas, bet ir tinkamai aprašyti atliktą tyrimą ir jo sprendimus. Vien bendrųjų metodinių nurodymų darbo aprašo rengimui studentui nepakanka, nes darbo aprašo turinys labai priklauso nuo darbo temos. Kadangi Informacinių sistemų inžinerijos srities temų įvairovė yra labai didelė, studentams yra sunku sudėlioti tinkamą darbo aprašo turinį, remiantis vien bendraisiais metodiniais nurodymais. Pasirinkto magistrinio darbo tikslas yra sudaryti geresnes sąlygas studentui rengti mokslinio tiriamojo darbo aprašą ir gerinti jo kokybę, sukuriant programų sistemą, kuri pasiūlytų aprašo karkasą, keletą šablonų jam užpildyti ir sugeneruotų aprašo eskizą. / There are a lot of research document types, and one of them is the master’s degree research document. When the student is doing his master’s degree document, he has to do a lot of research, search for a problem and provide the solution for that problem. Also he has to do an experiment for his thesis. All of the results and how it was achieved has to be written in the research document. Masters research document preparation is one of the more difficult tasks for the students. Like all of the research papers, there are certain specific requirements for each type. Also the structure depends for which semester the document is prepared for. Most of the students find that this is their first experience writing these kinds of documents. The common structure guidelines for the documents are not enough, because the content of the documents are very tightly linked to the student’s thesis, and its parameters: object, area, problem, solution. Because there are a lot of different theses in the information engineering area, it is hard for the students to create the primary research paper structure and content, only relying on the common guidelines given by the lecturers. Our proposed solution – a system, which would suggest a document structure and generate the research document primary version, provide comments, template phrases for specific sections of the document, e.g. writing the conclusion. Also the system will try to speed up the writing process, by providing with additional tools... [to full text]

Darbe buvo siekiama nustatyti paauglių priklausomybę sukeliančių medžiagų vartojimo sąsajas su šeimos, bendraamžių ir asmeniniais veiksniais. Tyrime dalyvavo 290 dviejų Vilniaus ir keturių Telšių vidurinių bei pagrindinių mokyklų (16 – 18 metų amžiaus) mokinių. Tyrime naudota anketa, kurią sudaro klausimai apie alkoholio ir kitų priklausomybę sukeliančių medžiagų vartojimo dažnumą, alkoholio ir kitų narkotikų vartojimo rizikingumui įvertinti naudojama Knight, Sherritt ir kt. (2002) parengta Crafft skalė. Paauglių priklausomybę sukeliančių medžiagų vartojimo šeimos, bendraamžių ir asmeniniai veiksniai matuojami klausimynu sudarytu, remiantis Hawkins, Catalano (1992) metodikos “Bendruomenės, kurios rūpinasi, jaunimo klausimynas” (angl. Communities That Care Youth Survey) šeimos, bendraamžių ir asmenine skalėmis. Pagal tyrimo rezultatus, paauglių alkoholio nevartojimo arba reto vartojimo galimybę didino mažiau išreikštas aštrių pojūčių siekimas, mažiau išreikštas psichoaktyvias medžiagas vartojančių draugų veiksnys, mažiau išreikštos palankios nuostatos į psichoaktyvių medžiagų vartojimą, iš šeimos veiksnių – mažiau išreikštos tėvų palankios nuostatos į psichoaktyvių medžiagų vartojimą. Kitų nei alkoholis ir tabakas medžiagų nebandymo galimybę didino mažiau išreikštas aštrių pojūčių siekimas, mažiau išreikštas psichoaktyvias medžiagas vartojančių draugų veiksnys, mažiau išreikštos palankios nuostatos į psichoaktyvių medžiagų vartojimą ir labiau išreikštas psichoaktyvių medžiagų... [toliau žr. visą tekstą] / The aim of the study was to assess adolescent substance use association with individual, peer, family factor. The subjects of the study were 290 adolescent (age 16-18) from two schools in Vilnius and four schools in Telšiai. Study questionnaire contains questions about alcohol and other substance use frequency. For evaluation of risks of alcohol and other substance use Knight, Sherritt et al. (2002) prepared Crafft scale was used. Adolescent addictive substance use family, peer and individual factors are measured by questionnaire based on Hawkins, Catalan (1992) questionnaire - Communities That Care Youth Survey family, peer and individual scales. According to the results of the research, adolescents no or low alcohol use possibility was increased by lower expression of sensation seeking, by lower expression of friends’ use of drugs factor, by lower expression of favourable attitudes towards drug use, from family factors - lower expression of favourable parental attitudes favourable towards drug use. Possibility of not trying other then alcohol and tobacco substances was increased by lower expression of sensation seeking, by lower expression of friends’ use of drugs factor, by lower expression of favourable attitudes towards drug use and higher expression of perceived risks of drug use, also by female sex. Non risky alcohol and other substance use possibility was increased by lower expression of sensation seeking, by lower expression of friends’ use of drugs factor, by lower... [to full text]

The aim of this thesis is to analyze how technological, economic, political and social factors can be integrated into Business Model for Geo-location database as a controlling entity for operation of Cognitive Radio devices in the TV White Space spectrum range. Tasks of thesis: to perform an analysis of scientific literature in the context of TVWS and to identify technologies of TVWS management, to find factors influencing Geo-location Database Business Model, to put forward Geo-location Database scenarios, to construct classification of Business Model for the Geo-location Database, to provide experimental study of feasibility to deploy distinct classification of Business Model for the distinct scenarios of Geo-location Database. Qualitative methods chosen for the research: exploratory literature analysis, consultations with experts/specialists and conceptual modelling based on scenarios. The exploratory part of the thesis describes existing spectrum shortage problem and presents potential technologies that can solve this problem. The theoretical part of this work introduces research methodology and the concept and principles of Business Model for technology innovation. Analytical part of the thesis seeks to identify potential Business Model configurations for the operations of Geo-location database in the TV White Space spectrum range. This part ends with presenting experimental study of the feasibility of Geo-location Business Model. The final part of the thesis concludes... [to full text] / Šio darbo tikslas – išanalizuoti, kaip technologiniai, ekonominiai, politiniai ir socialiniai faktoriai gali būti integruoti į verslo modelį, skirtą TV spektro tuštumų geografinei duomenų bazei, naudojančiai sumaniojo radijo ryšio sistemas. Tikslui pasiekti išsikelti uždaviniai: atlikti mokslinės literatūros analizę TV spektro tuštumų tema ir identifikuoti spektro tuštumų valdymo technologijas, nustatyti veiksnius, įtakojančius geografinės duomenų bazės verslo modelį, sudaryti geografinės duomenų bazės verslo scenarijus, sudaryti geografinės duomenų bazės verslo modelių klasifikaciją, nustatyti sudarytos verslo modelių klasifikacijos tinkamumą kiekvienam scenarijui bei nustatyti optimalią verslo modelio konfigūraciją. Uždaviniams įgyvendinti taikyti kokybiniai metodai: mokslinės literatūros analizė, konsultacijos su ekspertais bei specialistais, konceptualus modeliavimas, paremtas scenarijų metodu. Pirmoje darbo dalyje aprašomos egzistuojančios spektro trūkumo problemos ir apžvelgiamos potencialios technologijos, kurios gali išspręsti išanalizuotą problemą. Antroji darbo dalis pristato tyrimo metodus ir nagrinėja verslo modelį bei jo principus, galinčius įtakoti technologijos inovaciją. Trečioji darbo dalis siekia identifikuoti ir įvertinti potencialius TV spektro tuštumų geografinės duomenų bazės verslo modelius. Pateikiamos darbo išvados atsižvelgiant į darbo naudingumą, praktiškumą ir esamus apribojimus. Pagrindiniai darbo rezultatai: nustatyta optimali verslo modelių... [toliau žr. visą tekstą]

At the end analysis of forestry management was drew a conclusion – by financial activities was operated three models of Lithuania forestry management: budgetary financial in interwar Lithuania, budgetary and economical count financial in the period of Lithuania dependent, economical count financial in the open of Lithuania independence.

This master thesis deals with the virtual gate position and liquid level control system. The main characteristics of automatic control systems, fuzzy logic systems, their properties and formation principles are reviewed. Conventional and advanced control methods are presented pointing out their benefits, drawbacks and problems to be solved. Physical modelling and simulation issues are also discussed. Physical, mathematical, simulation and animation models of the system are produced. Position and level controllers are designed. The simulation of gate position and liquid level control processes is performed. The simulation model is built up using MATLAB Simulink and Fuzzy Logic Toolbox. The simulation results prove that the proportional controller fits very well for controlling gate position. However, the results of liquid level control “upwards” using PI controller are only satisfactory. Unsatisfactory results are obtained using the same controller for liquid level control “downwards”. Substantially better results are achieved using fuzzy logic controller. The models produced can be useful for further investigations and learning purposes.

Analysis of electromagnetic stepper motor at work have been performed. Types of stepper motors and its characteristics have been described generally. The programmes of modelling have been searching using internet and analysed. The programme QuickField 5.2 Studen‘s edition is in consort to demands and requests. Using QuickField 5.2 Student‘s edition the model of electromagnetic motor have been created and experimentations have been performed. Varying displacement of motor magnetic part the distribution of magnetic flux density and magnetic field lines have been analysed. The experimentations involving change of motors mechanical characteristics too (varying air gap between magnetic circuit and secondary part). Teoretical characteristics of distribution of magnetic field energy density, strenth and magnetic flux have been maked and compared. The conclusions and theoretical results specifying operating principle facility of electromagnetic motor. Characteristics of distribution of magnetic field and energy can be used for rating of influence to operation of motor.

The research object is probabilistic properties of non-coding DNA (nucleotide) sequences. Available models of DNA sequences are reviewed and their basic assumptions are verified by statistical analysis of bacterial DNA sequences. On the ground of this analysis, the definition of non-informative genetic sequence is introduced and a mathematical model of “genetic noise” is proposed. Computer simulations of non-coding (non-informative) nucleotide sequence evolution are performed and resulting sequences are compared with native ones. The task of visualisation of genetic sequences is an important part of the work. The main tasks of the work are the following: 1. to analyse the statistical features (independence, Markovity, long-range dependence, etc.) of bacterial DNA sequences, especially non-coding ones, 2. to formulate a definition of a non-informative nucleotide sequence (“genetic noise”) and to propose its mathematical model, 3. using the methodology of functional data analysis and the distance metrics between oligonucleotides, to propose an efficient method for nucleotide sequence visualisation. General Conclusions: 1. The probability model of non-informative nucleotide sequence or, in other words, “genetic noise” (an analogue of the “white noise”) is proposed and its properties are studied mainly by computer simulation. The long-range dependence in DNA sequences has been extensively studied and is considered as an evidence of their complexity and hierarchical structure... [to full text]

The research object is probabilistic properties of non-coding DNA (nucleotide) sequences. Available models of DNA sequences are reviewed and their basic assumptions are verified by statistical analysis of bacterial DNA sequences. On the ground of this analysis, the definition of non-informative genetic sequence is introduced and a mathematical model of “genetic noise” is proposed. Computer simulations of non-coding (non-informative) nucleotide sequence evolution are performed and resulting sequences are compared with native ones. The task of visualisation of genetic sequences is an important part of the work. The main tasks of the work are the following: 1. to analyse the statistical features (independence, Markovity, long-range dependence, etc.) of bacterial DNA sequences, especially non-coding ones, 2. to formulate a definition of a non-informative nucleotide sequence (“genetic noise”) and to propose its mathematical model, 3. using the methodology of functional data analysis and the distance metrics between oligonucleotides, to propose an efficient method for nucleotide sequence visualisation. General Conclusions: 1. The probability model of non-informative nucleotide sequence or, in other words, “genetic noise” (an analogue of the “white noise”) is proposed and its properties are studied mainly by computer simulation. The long-range dependence in DNA sequences has been extensively studied and is considered as an evidence of their complexity and hierarchical structure... [to full text]

Darbe „Akcijų kainų kintamumo analizė“ nagrinėjami ir lyginami Baltijos (Lietuvos, Latvijos, Estijos) bei Lotynų Amerikos (Meksikos, Venesuelos) šalių duomenys. Atliekama pasirinktų akcijų kainų grąžų analizė. Jai naudojami trijų metų kiekvienos dienos duomenys (akcijų kainos). Pirmoje darbo dalyje supažindinama su bendra prognozavimo metodų teorija, aprašomi skirtingi, dažnai literatūroje ir praktikoje sutinkami modeliai. Antrojoje dalyje aprašyti prognozavimo metodai taikomi realiems duomenims, t.y. pasirinktoms akcijoms. Prognozuojama akcijų kainų grąža, kuri po to yra palyginama su realia reikšme, apskaičiuojamos prognozavimo metodų paklaidos. Pagrindinis darbo tikslas – atlikti lyginamąją prognozavimo modelių analizę su pasirinktomis akcijomis ir atrinkti tuos metodus, kurie duoda geriausius rezultatus. Darbo tikslui įgyvendinti naudojama SAS statistinio paketo ekonometrikos ir laiko eilučių analizės posistemė SAS/ETS (Time Series Forecasting System). / Most of empirical surveys in macro and financial economics are based on time series analysis. In this work, data of Baltic and Latin America countries is being analyzed and compared. Analysis of stock price returns is presented using daily long term (three years) period data. In the first part of this work general forecasting theory is presented, also different methods, frequently met in the literature and practice, are described. In the second part, forecasting models are being applied for real data. We present results of forecasting stock returns comparing them with real values. Also a precision of forecasts is being calculated, which let us to decide about propriety of each model. Consequently, the aim of this work is to forecast returns of stock price by various time series models and to choose the best one. The analysis was made using SAS statistical package and its econometrics and Time Series Analysis System (SAS/ETS).

Šiame darbe pristatomas PLA formalizmo metodas, skirtas aprašyti ir imituoti hibridines sistemas, kurių tolydiniai komponentai aprašomi pirmos eilės diferencialinėmis lygtimis. Pasinaudojus PLA formalizmu suformuluosime Kvantuotų būsenų sistemos modelį (QSS). QSS modelis yra integravimu pagrįstas metodas, skirtas spręsti pirmos eilės diferencialines lygtis. Šis modelis buvo suformuluotas DEVS formalizmo aplinkoje, kuris yra giminingas PLA formalizmui. Hibridinės sistemos pavyzdžiu pasirinktas farmakokinetinis modelis. Farmakokinetika yra farmakologijos mokslo šaka, tyrinėjant vartojamų vaistų pasisavinimą ir absorbciją žmogaus kūne. Farmakokinetiniame modelyje vaistų pasiskirstymas aprašomas pirmos eilės diferencialines lygtimis. Tam, kad būtų galima aprašyti šį modelį QSS pagalba, buvo reikalinga patobulinti QSS modelį. Rezultate gautas pakeistas QSS modelis. Naudojant pakeistą QSS modelį buvo sudarytas farmakokinetinis modelis ir atliktas vaistų koncentracijos kitimo imitavimas paciento kūne, kai pacientas reguliuoja vaistų suleidimą. / This paper presents the method of using Piece Linear Aggregates formalism (PLA) for specification and simulation of hybrid systems, when continuous components are described in ordinary differential equations (ODEs). PLA is used to create Quantized State System (QSS) model. QSS is integration based method, created for ODE solving. Since QSS method first was introduced for use in Discreet Event Systems (DEVS) formalism, we adapted it for PLA formalism, which is fundamentally consanguineous to DEVS formalism. Pharmacokinetics model is used as example of hybrid system. Pharmacokinetics is a branch of pharmacology which describes administered drug absorption and distribution in human body. In pharmacokinetics drug distribution is described using ODE. In order to use drug injection in pharmacokinetics model, we have to modify standard QSS model and add some specific capabilities. In the result: modified QSS method was obtained and used for pharmacokinetic model specification. Simulation of morphine concentration in plasma was performed using real pharmacokinetics data to test Patient-Controlled Analgesia method effectiveness.