The non-linear model of pneumatic acting system, consisting of proportional directional control valve and symmetric rodless pneumatic cylinder is developed and investigated in this paper. This model enables to evaluate influence of essential nonlinearities concerned with working characteristics of airflow regulating valves and pneumatic cylinders on dynamics of the system. The modeling results of pneumatic acting system under several initial working conditions are presented and discussed in this article. The model reference based adaptive control method of force regulation in electro-pneumatic servo system is proposed and investigated in this paper to. This method allows eliminating of influence of nonlinearities of pneumatic cylinder and directional control valve on behavior of force regulation system. Therefore controllers of higher hierarchy level such as velocity and position controllers can be designed using conventional methods based on quantitative optimum. The modeling results of investigated system are presented in the paper.

The theme of Master project of Energetics engineer is to analize dispatch operating and problems of Distributing electricity network, sustaining analyse of nonfiction and generalize of experence practical work. Overlook dispatch operating functions and goals of Lithuanian electrical power company. Describe the information supply of dispatch team of Siauliai city. Analize the breakdown‘s information of Siauliai city department. Pending breakdowns count, the distribution time between breakdowns, present tne forecast of breakdowns.

Multiconductor line with non homogeneous dielectric is modeled and analyzed. Model of the multiconductor line is presented. The finite element method and Matlab PDE Tools software were used for analysis and calculation of characteristic impedances. The program for characteristic impedance calculation was developed. Calculation results are presented and analyzed. They confirm that the finite element method and the presented program can be used for calculations of characteristic impedances of multiconductor lines with non homogeneous dielectric.

The digital protection relay for 550 kW - 1 MW asynchronous motors is investigated in this finishing work. In the theoretical chapter are examinated the structure of multifunctional protection relay, non-regular asynchronous motor operating conditions and their reasons. Two operating conditions are marked out, first - when supply current is changed, second - alternation in supply voltage. Next is made investigation of Siprotec 7SJ621 digital protection relay. There's made survey of 630 kW power asynchronous motor from non-regular operating konditions when there was overcurrent and overvoltage in the supply.

Nowadays the popularity of WLANs is growing very rapidly. The basic solution for the connection of WLAN users to the global internet network is using leased lines or the other standard data transmission networks. But there may occur situations, when the only network for the data transmission we can use for the connection to the internet, is GSM network. In such a case, we are proposing to connect the users of WAN/WLAN networks by using GSM network, which has complete coverage in the territory of Lithuania. To guarantee the sufficient data transfer rate, we use bonding of several parallel GPRS/EDGE/UMTS channels into one total channel. In such a way we increase the reliability and data transfer rate of the total mobile data transmission channel. The parallel channels are bonded into one total channel by using either the hardware (Cisco) routers, or the software routers, configured using network administration tools of Linux operating system. In this work we give all the tools and configuration settings necessary for the realization of such a system. The results of QoS characteristics measurements are given too. We measure packet delay and data transfer rate. The majority of measurements are made by using several parallel GPRS channels because of wide spread GPRS technologies. The key accent of the system is free selection of the physical layer (OSI model) of the parallel channel. So we can bond either several GPRS, or EDGE, or UMTS channels.

The research object is to develop and investigate methods and algorithms for fmleexthiboldes ,c othnetr oplr oobfl etmwso -ocfo osradviinnagt ea nddri vrea tisoynsatel mhas.n dAlipnpgl inogf edneevreglyo,p eeqdu cipomnternotl and global material resources have to be investigated in cases of two dimensional positioning and scanning processes under circumstances omaximal.

The purpose of the research is to create traffic optimal adjustment methods and algorithms based on the theory of Petri nets. To investigate the functionality of created algorithms.

DEVELOPMENT AND RESEARCH OF SPECIAL LUMINAIRE SYSTEMS Relevance of the research When Lithuania were joined into the European Community it has become necessary to use lighting devices corresponding to requirements of the European Community – ENEC norms. Taking into account the specificity of given devices in Lithuania and other new EU countries they should be steady against low temperatures, humidity, acts of vandalism, to be suitable for the illumination of industrial buildings and to fulfil the requirements of low prices of the new incorporated countries. Recently new comprehensive ENEC norms (EN European Norms, EC Electrical Certification) for luminaires were drawn up and effectively introduced by the European Union. As a result, the production of a wide range of electrical operating equipment was discontinued due to the inconsistency between technical parameters of produced equipment and new norms. Such equipments were not allowed to be marketed. Therefore it has become necessary to develop luminaires capable to fulfil the increased quality requirements of the European Union. Their development should also taken into account due to the targets of product responsibility (§ 22) laid down in the Act for Promoting Closed Substance Cycle Waste Management and Ensuring Environmentally Compatible Waste Disposal introduced in 1996 also should be taken into account extensively the aspects of ecological efficiency. In the past, plastic luminaire systems belonging to a higher... [to full text]

DEVELOPMENT AND RESEARCH OF SPECIAL LUMINAIRE SYSTEMS Relevance of the research When Lithuania were joined into the European Community it has become necessary to use lighting devices corresponding to requirements of the European Community – ENEC norms. Taking into account the specificity of given devices in Lithuania and other new EU countries they should be steady against low temperatures, humidity, acts of vandalism, to be suitable for the illumination of industrial buildings and to fulfil the requirements of low prices of the new incorporated countries. Recently new comprehensive ENEC norms (EN European Norms, EC Electrical Certification) for luminaires were drawn up and effectively introduced by the European Union. As a result, the production of a wide range of electrical operating equipment was discontinued due to the inconsistency between technical parameters of produced equipment and new norms. Such equipments were not allowed to be marketed. Therefore it has become necessary to develop luminaires capable to fulfil the increased quality requirements of the European Union. Their development should also taken into account due to the targets of product responsibility (§ 22) laid down in the Act for Promoting Closed Substance Cycle Waste Management and Ensuring Environmentally Compatible Waste Disposal introduced in 1996 also should be taken into account extensively the aspects of ecological efficiency. In the past, plastic luminaire systems belonging to a higher... [to full text]

The main purpose of this research - to investigate the mechanical and working characteristics of single - phase induction motor with asimmtrical stator. The other purpose - to evaluate single phase motor use with frequensy transformer.