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Traffic congestion is increasingly becoming a severe problem in many large cities around the world. The problem is more complex in developing countries where cities are growing at a much faster rate than those in the developed world. Advanced Traffic Management Systems (ATMS) are one of the Intelligent Transport Systems (ITS) technologies that have been recommended and used as a tool to ease congestion problems in many large cities in the developing world. However, it is unknown how specific local conditions commonly observed in these cities, such as poor lane discipline and complex road user interactions, affect the performance of these systems. GETRAM (Generic Environment for Traffic Analysis and Modeling) was used in this research as a tool to develop microscopic traffic simulation models for the city of Bandung in Indonesia. The field data in this research, comprising throughputs, queue lengths and travel times, were collected during peak and off peak periods from all 90 signalised intersections connected to SCATS (Sydney Co-ordinated Adaptive Traffic System). This field data is believed to comprise one of the largest sets of “real world” data available for the development and validation of microscopic traffic simulation models. Two data sets were collected for this research: the first was used to develop and calibrate the simulation model and the second was used for validation. A number of statistical tests were used to determine the adequacy of the model in replicating traffic conditions. The results of statistical tests clearly showed that all of the calibrated and validated models reproduced field conditions with an acceptable degree of confidence. Therefore, the models were accepted as accurate and valid replications of the “real world”. The validated models were then used to evaluate the performance of SCATS which was implemented in Bandung in June 1997 as a pilot project. The results of comparative evaluation of the models under SCATS and under the Fixed Time control (without SCATS) demonstrated that SCATS did not necessarily always produce better results than the Fixed Time control. Furthermore, the performance of SCATS was strongly influenced by specific local conditions in the city. The multiple regression method was used to investigate the relationship between the traffic performance measures and significant basic variables. Based on this analysis, the main findings were: first, throughput was found to increase at intersections with higher v/c (volume to capacity) ratios. Second, throughput was found to decrease at intersections with higher numbers of phases and movements, longer widths of leg intersections, and farther distances to adjacent intersections. Third, queue length was found to increase at intersections with higher numbers of phases and movements. Based on the above findings, a number of improvements were recommended to enhance the performance of SCATS. This research also used traffic simulation to evaluate the impacts of these recommended improvements in increasing the performance of SCATS. The main findings from this evaluation were: first, restricted number of phases and movements at selected intersections substantially increased the traffic flow (78%) and decreased the queue length (by 55 to 67%) at the intersection. Second, making leg intersections wider—without physically building additional road capacity but by changing the stream with higher road hierarchy and higher v/c ratio from a two-way road into a one-way road—has a great impact on enhancing the performance of SCATS. Traffic flows were found to increase between 7 and 106%, and queue lengths were found to markedly decrease between 77 and 100% at all the suggested intersections. Third, the application of SCATS at intersections which are not closely spaced was not effective. Therefore, it is recommended that intersections which are not closely spaced remain under the Fixed Time control. The results and findings from this study provide road authorities in developing countries with an appreciation and enhanced understanding of the factors that influence the performance of traffic management systems in cities with similar characteristics to those in Bandung. These findings will also assist traffic engineers determine the best practices for the implementation of advanced traffic control systems in their cities.

Inside the master thesis there is represented computer simulation program of the gas flow through the two-stroke engine. The simulation program is developed in software package “Fortran” and is represented as Annex 2. The program simulates gas flow through the two-stroke engine and gives results of pressure changes and mass flow. The simulation is done by using concentrated volume method. The pressure inside the engine parts is described by pressure changes equation. The program is intended for the two-stroke engine tuning for the race. In the thesis is deeply investigated small swept volume engine used for tether model car race. Using the program is possible to do engine inlet and transfer timing optimization. The optimization results were very successful and showed that the cylinder filling with fresh air fuel mixture can be increased by 0.5%. For the numerical solution of the first order differential equations there were used Runge-Kutta IV method. / Magistriniame darbe pristatoma dvitakčio variklio modeliavimo programa, kuri apskaičiuoja dujų tekėjimą dvitakčiame variklyje. Programa sukurta naudojantis programiniu paketu „Fortran“ ir pateikta antrame priede. Programa modeliuoja dujų tekėjimą dvitakčiame variklyje ir pateikia slėgio bei debito rezultatus. Modeliavimui taikytas koncentruotų tūrių metodas. Slėgiai variklio dalyse yra aprašomi slėgio kitimo formule. Programa skirta lenktyniniams dvitakčiams varikliams, jų galiai didinti. Darbe labai smulkiai analizuojami mažo darbinio tūrio varikliai, kurie naudojami automobilių modelių greičio varžybose. Naudojant programą įmanoma atlikti variklio įsiurbimo ir prapūtimo fazių optimizavimą. Optimizavimo rezultatai rodo, kad galima pagerinti cilindro užpildymą šviežiu oro-kuro mišiniu net 0,5 % - tai yra labai geras rezultatas, kadangi dvitakčiai varikliai yra labai išvystyti. Pirmo laipsnio diferencialinėms lygtims spręsti panaudotas skaitinis Rungės-Kuto IV metodas.

In the final major degrees project was investigated the efficiency of loading equipment working in cargo terminals. In the beginning of project was simulated the methodology of loading equipment efficiency investigation and using it were analyzed container and metal store as terminal activity. Loading equipment working in container terminal were investigated using the theory of massive service. Also in the project were used economical and quantitative methods of management for detailed known of investigation object. In the investigation time of company AB “Lietuvos geležinkeliai“ were checked the few last years data of results in reloading works. Also in the project was investigated metal stores as cargo terminal modernization expedience, which was reasoned by calculations of productivity and according it was formulated the investment project for cranes and were given suggestions and conclusions. The main purposes of this project were to create methodology of loading equipment efficiency investigation and to analyze the expedience of loading equipment working in some Lithuanian metal stores.

Usually used oil fuel limits get lower, fuel prices get higher and air pollution becomes big problem. These problems can be solved using anternative fuel or alternative fuel mixtures. There are several alternatives instead of usually used oil fuel for internal combustion engines in Lithuania. Thermal cycle calculation of Internal Combustion Engine (ICE) using several alternative fuels and alternative fuel mixtures shows lower emissions, changes in power curve and raised fuel consumption. VW Passat 1.6 engine test with biogas is made to find out ICE Power and rotation moment diagrams and functions.

In the Final Master’s Thesis, the character of faults of principal systems in buses “Karosa B-741” exploited upon the conditions of JSC “Vilniaus autobusai” is analyzed and an assessment of technical service technologies by fault rate is provided. The regularities of frequencies of faults of the principal systems are searching, the causes of appearance of faults and dependence on seasons are cleared up. The technical service periodicity usable by the bus manufacturer and the enterprise engaged in bus exploitation are analyzed as well. In the Paper, the concept of technical exploitation and the ways of collection the data on exploitation reliability are presented. The system of technical service and the technological processes are described. Statistical processing of the distribution of the most frequent faults is carried out and their middle resource is found. Dependence on run of fault of the principal systems are analyzed; an assessment of the technical service periodicity is carried out. The conclusions from the Final Paper and proposals are provided. Taking into regularities of faults it‘s offering to estimate by correction of the bus manufacturer technical service periodicity, especially in cold season. The Paper includes: the introduction, four parts, conclusions and suggestions, the list of references. Thesis consist of: 101 text without extras, 33 figures, 18 tables, bibliographical entries. The annexes are enclosed hereto.

The Purpose of the Dissertation is to analize and specify the capability of cargo flow forecasting in ports, through assessment and modelling the distribution of cargo flows throughout competitor ports, by considering certain factors that might cause considerable changes into ports or port environment.

Pasaulio ekonomikos augimas, spartėjantis globalizacijos procesas, technologijų pažanga didina atstumus tarp žaliavų gavimo, gamybos ir pagamintų prekių naudojimo taškų. Gausėjant prekybinių ryšių bei plečiantis jų geografijai, didėja reikalavimai transporto ir logistikos paslaugas teikiančiam sektoriui. Regionų ekonominis augimas priklauso nuo to, kaip transporto sistema geba patenkinti žaliavų tiekėjų, gamintojų, prekybininkų ir vartotojų logistikos poreikius laiko, greičio, saugumo, sąnaudų prasmėmis. Transporto srautai ilgainiui prisitaiko prie kintamų regiono logistikos poreikių, tačiau dėl transporto sistemos inertiškumo tam sugaištama laiko. Lietuvoje reikšminga dalis bendrojo nacionalinio produkto sukuriama transporto ir logistikos sektoriuje, kadangi šalis yra stambių tranzitinių krovinių srautų kryžkelėje. Lietuvai tapus Europos Sąjungos nare, atsiveria tarptautinės prekybos augimo galimybes, Lietuva tampa Europos Sąjungos buferine zona prekybai su Rytų bloko šalimis, taigi teisinga Lietuvos transporto sistemos plėtros strategija gali suteikti Lietuvai didžiulį ekonominį potencialą, bendrojo vidaus produkto ir darbo vietų skaičiaus augimo perspektyvas. Transporto srautams užtikrinti būtina transporto infrastruktūra, kurios plėtrai yra labai svarbu nustatyti potencialius krovinių srautus. Transporto infrastruktūra labai imli kapitalui, todėl jos plėtros kryptys turi tiksliai atitikti logistikos poreikius, priešingu atveju milžiniškos investicijos nepateisinamos... [to full text] / Relevance of the dissertation is determined by the object of research – the influence of logistical factors on transport flows distribution. The growth of world economics, business globalization, progress in technology skills extends the distances between geographical points of raw materials resources, manufacturers and consumers. Due to the membership in the European Union (EU) Lithuania has got new opportunities for international trade growth, and all the Eastern Baltic countries have become the buffer region for the EU trading with the countries of the Eastern Europe and Asia. A proper transport policy and infrastructure development would increase significantly the GNP in warehousing, transport and distribution sectors. Forecasting of potential transport flows according to logistical requirements of freight suppliers is most important for transport network optimization. Scientific problem. Contemporary transport engineering theory approaches the peculiarities of transport flows formation too narrowly, only as an analysis of internal factors determining freight flows. There is no analysis of external factors. Many researchers assume that transport flows are determined only by the existing transport network and its characteristics. Other researchers consider transport flows as a result of logistic elements only. The estimating of internal and external logistical factors provides a possibility to forecast the transport flows. Aim of the research is to create a model of... [to full text]

Relevance of the dissertation is determined by the object of research – the influence of logistical factors on transport flows distribution. The growth of world economics, business globalization, progress in technology skills extends the distances between geographical points of raw materials resources, manufacturers and consumers. Due to the membership in the European Union (EU) Lithuania has got new opportunities for international trade growth, and all the Eastern Baltic countries have become the buffer region for the EU trading with the countries of the Eastern Europe and Asia. A proper transport policy and infrastructure development would increase significantly the GNP in warehousing, transport and distribution sectors. Forecasting of potential transport flows according to logistical requirements of freight suppliers is most important for transport network optimization. Scientific problem. Contemporary transport engineering theory approaches the peculiarities of transport flows formation too narrowly, only as an analysis of internal factors determining freight flows. There is no analysis of external factors. Many researchers assume that transport flows are determined only by the existing transport network and its characteristics. Other researchers consider transport flows as a result of logistic elements only. The estimating of internal and external logistical factors provides a possibility to forecast the transport flows. Aim of the research is to create a model of... [to full text] / Pasaulio ekonomikos augimas, spartėjantis globalizacijos procesas, technologijų pažanga didina atstumus tarp žaliavų gavimo, gamybos ir pagamintų prekių vartojimo taškų. Lietuva tapusi Europos Sąjungos nare, tampa Europos Sąjungos buferine zona prekybiniams mainams su Rytų Europos ir Azijos šalimis. Lietuvos transporto sistemą būtina pritaikyti esamiems ir potencialiems tarptautiniams krovinių srautams aptarnauti. Transporto srautų formavimosi išorinių veiksnių nustatymas ir įvertinimas Lietuvos transporto strategijoje gali suteikti šaliai didžiulį ekonominį potencialą.