bluuebunny/crossref_metadata_2025 huggingface dataset:
Migración con rostro de niños, niñas y adolescentes
Authors: Caballeros Álvaro
Published: December 2011

El artículo presenta un análisis descriptivo de los niños, niñas y adolescentes migrantes no acompañados que fueron deportados y atendidos por el Hogar Casa Nuestras Raíces de la Secretaría de Bienestar Social de la Secretaría de Bienestar Social de Guatemala. La información presentada se deriva de los registros del Centro, de entrevistas realizadas con los niños, niñas y adolescentes atendidos en el mismo, y en datos oficiales del Instituto Nacional de Migración de México. El artículo presenta un panorama de la experiencia de la niñez migrante, las circunstancias del viaje, el proceso de deportación y de reinserción en sus países de origen. El autor señala que la atención y protección que reciben los niños, niñas y adolescentes por parte de autoridades migratorias y sociales ha mejorado considerablemente, sin embargo, no se adecúa al enfoque de derechos humanos.
Comentario al libro: "Expulsados de la globalización: políticas migratorias y deportados centroamericanos" de José Luis Rocha
Authors: Parducci Amparo Marroquí
Published: December 2011

En muchos momentos se ha señalado (y me parece que con razón) que el conocimiento académico se ha quedado sin nada que decir a la sociedad. Muchas investigaciones terminan en gavetas. Las discusiones y análisis sobre la realidad, el papel del estado y los problemas de seguridad o corrupción que nos habitan han pasado de los auditorios universitarios a elegantes salones de hoteles donde algunos se dan cita para discutir lo urgente.
The Loss of Resistance Nerve Blocks
Authors: Singh Shiv Kumar , Gulyam Kuruba S. M.
Published: December 2011

Presently ultrasound guided nerve blocks are very fashionable but vast majority of people around the world cannot practice these techniques mostly due to lack of resources but even in the developed countries there is lack of training which precludes people from using it. Lack of resources does not mean that patient cannot be provided with appropriate pain relief using nerve blocks. There are some nerve blocks that can be done using the loss of resistance (LOR) techniques. These blocks like, tranversus abdominis plane (TAP), rectus sheath, ilio-inguinal and fascia iliaca blocks can be effectively utilized to provide pain relief in the peri-operative period. For these blocks to be effectively delivered it is essential to understand the anatomical basis. It is also important to understand the reasons for failure, which is mostly due to delivery of the local anaesthetic in the wrong plane. The technique for LOR is not only simple and effective but also it can be delivered with minimal resources. This article deals with the techniques used for LOR blocks, the relevant anatomy and the methods used to administer the blocks. The article also describes the various indications where these blocks can be utilized, especially in the post-operative period where the pain management is sub-optimal.
Reprogramming of Human Huntington Fibroblasts Using mRNA
Authors: Arnold Antje , Naaldijk Yahaira M. , Fabian Claire , Wirth Henry , Binder Hans , Nikkhah Guido , Armstrong Lyle , Stolzing Alexandra
Published: December 2011

The derivation of
induced pluripotent stem cells (iPS) from human
cell sources using transduction based on viral
vectors has been reported by several
laboratories. Viral vector-induced integration
is a potential cause of genetic modification. We
have derived iPS cells from human foreskin,
adult Huntington fibroblasts, and adult skin
fibroblasts of healthy donors using a nonviral
and nonintegrating procedure based on mRNA
transfer. In vitro transcribed mRNA for 5
factors, oct-4, nanog, klf-4, c-myc, sox-2 as
well as for one new factor, hTERT, was used to
induce pluripotency. Reprogramming was analyzed
by qPCR analysis of pluripotency gene
expression, differentiation, gene expression
array, and teratoma assays. iPS cells were shown
to express pluripotency markers and were able to
differentiate towards ecto-, endo-, and
mesodermal lineages. This method may represent a
safer technology for reprogramming and
derivation of iPS cells. Cells produced by this
method can more easily be transferred into the
clinical setting.
Solar Irradiance Model for Solar Electric Panels and Solar Thermal Collectors in Lithuania
Authors: Vasarevicius D. , Martavicius R.
Published: December 2011

Presented the model based on the clear sky standard, which allows calculation of solar insolation values at each location in Lithuania. Model is associated with geographical coordinates of Lithuania and local time of every day of the year. It is made for modeling electronic systems for management of solar panels and solar thermal collectors. Model was tested by calculating solar insolation at 313 369 locations of Lithuania. It is shown that the lowest insolation in territory of Lithuania on noon of June 21 is 375 m2 and the highest is – 439 W/m2. Deviation of solar insolation values from average is ±8%. In addition, it is shown that the changes in solar insolation are caused by zenith or altitude angle variations. Model is suitable for calculation of optimal angles of solar panels and solar thermal collectors in any location of Lithuania. Ill. 4, bibl. 8 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.132
Impact of Wireless Channel Parameters on Quality of Video Streaming
Authors: Paulikas S. , Sargautis P. , Banevicius V.
Published: December 2011

The problem of estimation of video quality obtained by end-user for mobile video streaming is addressed. Widely spreading mobile communication systems and increasing data transmission rates expand variety of multimedia services. One of such services is video streaming. So it is important to assess quality of this service. Consumers of video streaming are humans, and quality assessment must account human perception characteristics. Existing methods for user experienced video quality estimation as quality metrics usually usebit-error rate that has low correlation with by human perceived video quality. More advanced methods usually require too much processing power that cannot be obtained in handled mobile devices or intrusion into device firmware and/or hardware to obtain required data. However, recent research shows that channels throughput dedicated to some service (e.g. video streaming) can be tied to QoS perceived by an end-user indicator. This paper presents a research on impact of wireless channel parameters such as throughput and jitter on quality of video streaming. These wireless channel parameters can be easily obtained by monitoring IP level data streams in end-user’s device by fairly simple software agent for indication of video streaming QoS. Ill. 5, bibl. 10 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.138
Adaptive Cross-layer Optimization Based on Markov Decision Process
Authors: Velickovic Z. , Jevtovic M.
Published: December 2011

In order to satisfy QoS demands of wireless multimedia application it is necessary to make an optimization on several ISO-OSI layers in the protocol stack. In this paper an optimization cross-layer algorithm has been applied based on Markov decision process (MDP). The wireless communication system with one user has been optimized by the transmitting policies in order to maximize the throughput along with the optimization of the average value of the engaged power, satisfying the demanded BER and the average value of rejected packets. Simulation results show that the application of cross-layer design based on MDP is justified. Ill. 2, bibl. 9 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.141
The Analysis of Network Performance with Different Routing and Interconnection Methods
Authors: Kostic-Ljubisavljevic A. , Mladenovic S. , Acimovic-Raspopovic V. , Samcovic A.
Published: December 2011

The effects of dynamic traffic routing and interconnection charging methods on telecommunication network load balance are analyzed in this paper. The results of numerous simulations performed with software specially developed for analysis of network performances are given. It is shown that adequately chosen routing method can give good balancing of link loads which impacts the choice of networks interconnection charging agreement. Ill. 7, bibl. 11 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.142
Generalized Mathematical Model of Controlled Linear Oscillating Mechatronic Device
Authors: Senulis A. , Eidukas D. , Guseinoviene E.
Published: December 2011

This paper presents the general mathematical model of double-sided splingless linear oscillating mechatronic device – oscillating motor- ompressor which is supplied by thyristor voltage converter. The model presents possibilities to evaluate losses of the windings and losses in the magnetic circuit, nonlinear inductances, mutual inductances, special current feedback using harmonic analysis for the control, oscillations not only of the moving part, but also the “stator” oscillations. Also using this model such parameters can be calculated – oscillation centre drift, oscillating coordinates and velocities of mover and stator, all currents and voltages, electromagnetic force, harmonics of each time-dependent parameter. Ill. 7, bibl. 13 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.145
Using Bayesian Network for Robot Behavior with Sensor Fault
Authors: Rezaee A. , Raie A. , Nadi A. , Shiry S.
Published: December 2011

The paper discussed application of Bayesian network to learn behavior of mobile robot in presence of fault sensor. Theoretical and practical are considered for checking the results. Robot's model was considered as Bayesian model that each value of CPD was learned. This framework shows that can be work in real environment with noisy sensor. Ill. 12, bibl. 7, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.152
Comparison of Two 12-Key Assignments on Mobile Devices
Authors: Dagiene V. , Grigas G. , Jevsikova T.
Published: December 2011

Two variants of key assignments on 12-key mobile devices for languages based on Latin script are discussed. It is shown that the variant where all letters of the alphabet of a particular language are placed in front of digits is more preferable than that where letters with diacritics are placed after digits. The investigation was conducted, using Lithuanian, Latvian and Polish alphabets as the examples. However, all the results and conclusions, presented in the paper, are valid for any Latin script language, using the alphabet with more than 26 letters of basic Latin set. Ill. 1, bibl. 15, tabl. 5 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.153
A Hybrid GA-PSO Approach Based on Similarity for Various Types of Economic Dispatch Problems
Authors: Guvenc U. , Duman S. , Saracoglu B. , Ozturk A.
Published: December 2011

Economic dispatch problem is an optimization problem where objective function is highly nonlinear. In this paper, an efficient method based on hybrid genetic algorithm- particle swarm optimization (GA-PSO) for economic dispatch (ED) problem is proposed. In the proposed method, children created by using similarity measurement between mother and father chromosomes relationship. The feasibility of the proposed approach is demonstrated for solve various types of economic dispatch (ED) problems in power systems such as, economic dispatch with valve point (EDVP) effects, the ED of generators with prohibited operating zones and ED with only fuel options and it is compared in the recent literature. The study results show that the proposed approach is more efficient in finding higher quality solutions in various type ED problems. Ill. 3, bibl. 20, tabl. 10 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.108.2.155
Computer Terminal for Blind and Visually Impaired
Authors: Bansevicius R. , Zvironas A. , Virbalis J. A.
Published: December 2011

The computer terminal is a ferromagnetic plate with spacial configuration. on which the blind moves by his finger the sensor of a ferromagnetic material. The finger feels the variations of the friction force due to variations of magnetic field and its frequency, which can represent the variations of the different visual information. The magnetic field is created by the spiral electromagnet. It is situated under all terminal and is created the sufficiently uniform magnetic field with well resolution. Analysis of the electromagnet magnetic circuit is performed. Ill. 5, bibl. 6 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.159
Position Measurement of Oscillating Linear Movement of Mechatronic Device
Authors: Jankūnas V. , Eidukas D. , Guseinovienė E.
Published: December 2011

The problem of measurement of the curve of movement of oscillating synchronous electric devices is discussed. To achieve the purpose system, the light emitting diode (LED) - slit - linear optical sensor is used. Different color LEDs are linked with different moving parts and optical sensor with the lines of the elements sensitive to different colors, are used to simplify measurement system. Practical implementation of measurement system is presented. Ill. 8, bibl. 4 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.160
Output Power of Switched Reluctance Generator with regard to the Phase Number and Number of Stator and Rotor Poles
Authors: Hrabovcova V. , Rafajdus P. , Liptak M.
Published: December 2011

This paper deals with comparison of the SRG output power with regard to the phase number and number of stator and rotor poles. An optimal topology of SRG magnetic circuit from the point of view of achieved output power is investigated by means of FE analysis. On the base of presented mathematical model the output power is simulated for two kinds of single phase and five kinds of multiphase topologies. Some measurements are carried out in motoring mode and compared with FEM investigations and simulations to verify mathematical model of SR machine. Ill. 12, bibl. 12, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.164
Study on the Characteristics of Electronically Commutated Motor
Authors: Karaliunas B.
Published: December 2011

The article presents the study on the electrically commutated DC motors or on the so called studies of the fields of application of brushless motors, considering their advantages and disadvantages. The computerized simulation model Matlab/Simulink of the characteristics of the EC motor was compiled, their units of operation were described as well as the methodology of their simulation. There are presented the curves of the change of the electromotive force induced in the phase winding of the motor, the cur rents and the moments of the motor under the various velocities of the rotor rotation. The obtained results indicate that the efficiency of the commutated motor depends on the accuracy of the commutation moment of the stator windings. Ill. 4, bibl. 5 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.165
Modeling of Photovoltaic Panel and Examining Effects of Temperature in Matlab/Simulink
Authors: Rustemli S. , Dincer F.
Published: December 2011

This study proposes general and specific modeling and simulation for Lorentz LA30-12S photovoltaic panel. This panel has monocrystalline cell technology. The panel power parameters are examined under observing different panel temperatures. It is created a special function for this system by Matlab/Simulink programmer. Also, the different solar radiation values are taken into account. The model for the proposed range of irradiance and temperature as model inputs, with the corresponding values of voltages, currents, and power as outputs is presented. Simulation results are compared by doing power calculations. The simulation results show that a photovoltaic panel output power reduces as module temperature increases. This situation is showed with Matlab/Simulink graphics. Ill. 13, bibl. 24, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.166
Visualisation of Space-Temporal Configuration of Low Frequency Magnetic Signals
Authors: Dimitrov D. , Dimitrov A.
Published: December 2011

Some methods for calculation and computer visualization of space configuration of low frequency magnetic field, used in magneto-therapy is described in the paper. The subject of present paper is connected especially with moved magnetic wave. A mathematical method for calculation of magnetic induction in different points in the case of application of several pairs of air coils is done. Some results obtained by computer visualization of space configurations in the cases of one pair of coil and several pairs of coils are done. A computer visualization of space configuration of moved low frequency magnetic field in the case of medical therapy is done on the base of suggested method for investigation. Ill. 7, bibl. 6 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.168
Three-Mode Biomedical Signal Denoising in the Local Phase Space based on a Tensor Approach
Authors: Pukenas K.
Published: December 2011

In this research, an improved local projection noise reduction approach with three-mode model of neighborhood is proposed. Firstly, one dimensional time series are embedded into a high dimensional phase space. Secondly, the neighborhood tensor of each reference no overlapping window with several consecutive vectors of reconstructed phase-space is computed rather than neighborhood matrix of each separate vector. Lastly, with the suggested model a higher order singular value decomposition (HOSVD) is performed on the neighborhood tensors to split the three mode data into two orthogonal subspaces: the signal and noise subspaces. Throughout the experiment, the effectiveness of the proposed method is validated with a noisy simulated data — the x component of Rossler system and real biomedical signal contaminated with additive white Gaussian noise. Ill. 3, bibl. 14 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.169
Speckle Tracking Derived Left and Right Atrial, Left and Right Ventricular Strain, Strain Rate After Atrioventricular Node Slow Pathway Radiofrequency Ablation
Authors: Sileikiene R. , Vaskelyte J. , Mizariene V. , Jurkevicius R. , Bluzaite I.
Published: December 2011

Impairment of atria and ventricular function may occur after radiofreąuency ablation (RFA) of AV node slow pathway in the case of tachycardia. The 2D speckle tracking imaging technique was used for quantification of global and regional function of the heart at late follow-up in children who underwent RFA of slow pathway. The study group consisted of 22 children who underwent RFA 5, 5 (2,5) years ago and 20 healthy children. The age was comparable between the groups. The study revealed no impairment of global and regional function of the ventricles and increased atria volumes, reduced regional atrial myocardial deformation parameters in children late after RFA. One of the possible cause of reduced atrial function may be negative effect of radiofrequency ablation. Bibl. 11, tabl. 9 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.171
On Delay Test Generation for Non-scan Sequential Circuits at Functional Level
Authors: Bareisa E. , Jusas V. , Motiejunas K. , Seinauskas R.
Published: December 2011

Sequential circuit testing has been recognized as the most difficult problem in the area of fault detection. High-performance circuits with aggressive timing constraints are usually very susceptible to delay faults. We investigated the application of tests that are generated at functional level for detection of gate-level transition faults. Based on experimental results, we developed a framework of delay test generation for non-scan sequential circuits. The provided comparison with experimental results of other approaches demonstrates the effectiveness of proposed framework. Bibl. 13, tabl. 4 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.173
FPGA based Improved Hardware Implementation of Booth Wallace Multiplier using Handel C
Authors: Shinde S. A. , Kamat R. K.
Published: December 2011

Applications requiring intensive arithmetic operations such as multiplication are exponentially increasing than ever before. The state of art FPGAs are the preferred implementation platforms for implementation of multipliers inspite of the speed and area issues. In this paper we present implementation of Booth Wallace Multiplier on Xilinx FPGAs. Our approach employs design at the higher level of abstraction using Handel C which also inculcates parallelism at the algorithmic level. Ill. 4, bibl. 4, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.174
Modelling of the Computer Classroom Electromagnetic Field
Authors: Baltrenas P. , Buckus R. , Vasarevicius S.
Published: December 2011

Operation of office, video and audio equipment generates electromagnetic fields. Many employees who use computers for a long time complain of headaches and other health troubles. This has become a serious problem as electromagnetic fields are invisible and intangible and an employee, therefore, is unaware of how to protect oneself from them. This work involves modelling of the strengths of computer-generated electric and magnetic fields in the frequency ranges 5 Hz - 2 kHz and 2 kHz - 400 kHz in a computer classroom. After measuring the initial parameters of an electric and a magnetic field, electromagnetic fields propagating in the classroom were modelled with the help of the software VIZIMAG. Propagation and directions of electromagnetic field isolines are also presented. The modelling software VIZIMAG allows us to identify the strength of electric field or the frequency of magnetic field as well as the area of a room where they are present. Separate models are designed for both electric strength and magnetic flux density. Ill. 9, bibl. 11, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.175
Evaluation of the Mobile Robot Position according to the Profile of Known Environment
Authors: Baranauskas V. , Derviniene A. , Sarkauskas K. , Bartkevicius S.
Published: December 2011

Method of evaluation of the mobile robot position according to the profile of known environment is suggested and verified. Algo-rithm of coordinates evaluation according to the profile of known environment operates reliably if deviation from real coordinates is considerable, scanner mensuration are affected using white noise and if there are several robots in the scanning environment. However it is necessary that equipment of orientation in environment should be included in mobile robot. Verification of the coordinates should be performed frequently. This procedure should be performed by control system of the robot. Ill. 6, bibl. 7 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.177
Optimization of a Mini-Golf Game using the Genetic Algorithm
Authors: Coskun A.
Published: December 2011

While playing golf, it is important that the ball must be conveyed to the defined target point by making the minimum number of shots. The chosen algorithm and the applying techniques for conveying the ball to the targeted point are significant in optimizing this game. A research has been carried out on the basic concepts of the genetic algorithm in this study, and has been concentrated on how this algorithm can be applied on a physics problem. Properties those have learnt as a result of the carried out research have been applied to the problem by making various arrangements as required by the nature of the problem for conveying the ball to the target point in optimizing of a mini-golf game. Effects of the presented genetic algorithm elements over the calculation time of the solution of the problem have been evaluated by various tests during the application process. It has been observed that the genetic algorithm is effective in determining the required velocity and direction components for conveyance of the ball to the target point. Ill. 1, bibl. 5, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.180
The Utilization of Feedback and Emotion Recognition in Computer based Speech Therapy System
Authors: Schipor O. A. , Pentiuc S. G. , Schipor M. D.
Published: December 2011

In this paper we present two appropriate ways for the Computer Based Speech Therapy (CBST) improvement. Real-time quality feedback in free environments and emotion recognition could produce a better similarity between human and artificial speech therapist. Using these extended approaches, a CBST system can become a better speech therapist assistant and that is why we intend to implement these technology improvements on our CBST system - Logomon. Ill. 3, bibl. 15 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.181
Method for Conversational Voice Quality Evaluation in Cellular Networks
Authors: Kajackas A. , Anskaitis A. , Gursnys D.
Published: December 2011

In this paper, method for evaluation of varying conversational speech quality in wireless communications is proposed. The proposed algorithm evaluates quality degradations using indicators based on count of lost frames and voice activity indications. The correctness of proposed algorithm is investigated by comparison of test results with results obtained using PESQ algorithm under same conditions. The achieved average correlation coefficient is 0.975. This result is independent of frame loss model and percentage of silence in test sentences. Proposed algorithm can be implemented in mobile stations and used for speech quality evaluation by real conversation. Ill. 3, bibl. 13, tabl. 3 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.182
Digital Broadcasting Techno-Economic Efficiency Simulation Model
Authors: Sugaris A. , Reljin I.
Published: December 2011

An estimation method of system cost, associated revenue and estimated profitability that applies to the broadcasting standards used in digital terrestrial networks is presented. The purpose of this research is to support and promote the adoption of innovative technologies that improve spectrum efficiency and flexible usage. The model presented should help key players to make choice on digital terrestrial broadcasting technologies driven by optimal investment cost and the techno-economic analysis. The results clearly show the early (in realistic multiple-multiplex cases even immediate) profitability of broadcast network if MPEG-4 and DVB-T2 standards are used. Ill. 6, bibl. 6, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.183
The Magneticreactive Effect in Transistors for Construction Transducers of Magnetic Field
Authors: Osadchuk V. S. , Osadchuk A. V.
Published: December 2011

In the given article the method of build-up of radiomeasuring transducers of a magnetic field on a basis magneticreactive effect in bipolar and field-effect transistors is offered. It is shown, that change of a reactive component of a complete resistance from induction density on electrodes a source - drain of a field-effect transistor makes 0,6 Ohm/mT, and for the bipolar transistor on electrodes the emitter-collector - 12,5 Ohm/mT. Such changes of reactive components of a complete resistance are essential, that confirms an opportu-nity of practical application of these effects for making microelectronic radiomeasuring transducers. The circuit of the transducer of a magnetic field on field-effect transistors which sensitivity makes from 510 up to 3500 Hz/mT is offered. Ill. 3, bibl. 8 (in English; ab-stracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.109.3.185
Modelling and Design of HF 200 kHz Transformers for Hard- and Soft-Switching Application
Authors: Radvan R. , Dobrucky B. , Frivaldsky M. , Rafajdus P.
Published: December 2011

The paper deals with modelling and design of HF 200 kHz (and more) low-power transformers with determinated leakage induct-ances for both hard- and soft-switching applications. The first group features by small value of the leakage inductance contrary to sec-ond one demanding that value substantially higher. The further aims of the design are minimized weights and dimensions of the trans-formers. Results of numerical simulations and experimental verifications of designed transformers operated in converter circuits are given at the end of the paper. Ill. 13, bibl. 5, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.276
Investigation of Energetic Parameters of Oscillating Synchronous Pulsating Current Motors
Authors: Urmoniene L. , Gecys S. , Guseinoviene E. , Cirtautas V.
Published: December 2011

This paper deals with oscillating linear synchronous pulsating current motor compressor drive supplied by sinusoidal and rectangular voltage. While creating mathematical model of the motor for investigation, Matlab software was used for solving of differential equations. Modeling results while supplying motor by sinusoidal and rectangular voltage and changing firing angle a of thyristor, frequency of voltage f and a load R. Characteristics and energetic parameters of oscillating linear pulsating current motor were obtained and analyzed. Ill. 10, bibl. 6, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.278
The Air Gap and Angle Optimization in the Axial Flux Permanent Magnet Motor
Authors: Akuner C. , Huner E.
Published: December 2011

In this study, the axial flux permanent magnet motor and the length range of the air gap between rotors was analyzed and the appropriate length obtained. NdFeB permanent magnets were used in this study. Permanent magnets can change the characteristics of the motor's torque. However, the distance between permanent magnets and the air gap will remain constant for each magnet. The impact of different magnet angles for the axial flux permanent magnet motor and other motor parameters was examined. To this aim, the different angles and torque values of the magnetic flux density were calculated using the finite element method of analysis with the help of Maxwell 3D software. Maximum torque was obtained with magnet angles of 21°, 26°, 31.4°, and 34.4°. Additionally, an important parameter for the axial flux permanent magnet motor in terms of the air gap flux was analyzed. Minimum flux change was obtained with a magnet angle of 26°. The magnetic flux of the magnet-to-air-gap is under 0.5 tesla. Given the height of the coil, the magnet-to-air-gap distance most suitable for the axial flux permanent magnet motor was 4 mm. Ill. 11, bibl. 4, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.280
Data Post-Processing Algorithms for Active Forward-Looking Sonar System
Authors: Berdnikova J. , Kozevnikov V. , Ruuben T. , Raja A.
Published: December 2011

This paper introduces a new beamforming and received data post-processing method for forward-looking sonar applications with limited number of array elements. Applications like Sidescan or Forward Looking Sonars, used for area efficient sea floor imaging, collect large amount of raw data, which allows us to do both imagery and additional data processing. Moreover, object localization improvement could be accomplished by the post-processing of the received information collected with digital beamforming and beam focusing. Test results illustrate the efficiency of the proposed post-processing algorithms in terms of angular aperture and target detection. Ill. 11, bibl. 8 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.284
Synthesis of Six-Conductors Symmetrically Coupled Microstrip Line, Operating in a Normal Mode
Authors: Mikucionis S. , Urbanavicius V.
Published: December 2011

Synthesis technique of six-conductor symmetrically coupled microstrip multiconductor line (MMCL), operating in a normal mode, is presented in this article. Results of the calculations acquired using the proposed mathematical model of an MMCL differ only by 3 % from the results acquired by other researchers. Examples of synthesis of six-conductor symmetrically coupled MMCL, operating in the even- and odd normal modes, are submitted in the article, also, dependences of parameters of these lines are investigated. It was established that the external conductors of an MMCL impart the most for ensuring the normal mode in an MMCL, and the organization of the internal conductors remains regular in this case. It is shown that parameters of the synthesized MMCL operating in the even normal mode depend in greater degree on the space between conductors, than MMCL operating in the odd normal mode. Ill. 7, bibl. 27, tabl. 2 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.285
The Magnetoactive p-Ge Rod Waveguide Loss Analysis on the Concen-tration of Two Component Hole Charge Carriers
Authors: Nickelson L. , Bubnelis A. , Baskys A. , Navickas R.
Published: December 2011

In this work are examined the phase and attenuation constants of open magnetoactive p-Ge rod waveguides. Our algorithm allows ana-lyzing the very high waveguide losses. Dispersion characteristics of p-Ge with two component hole charge carriers waveguide are calculated when the ratio of heavy holes' concentration in the material is equal to 10%, 30% and 90% of the total free carrier concentration. Dispersion characteristics of the main helicon and eight higher helicon modes are presented here. There are the degeneration and the transformation of higher hybrid modes at some heavy holes' concentrations. The waveguide broadbandwidth can be considerably extended due to the fact that the losses of the higher modes are considerably larger in comparisons to the main mode loss at the certain heavy holes' concentration. Ill. 6, bibl. 12 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.286
The Microelectronic Radiomeasuring Transducers of Magnetic Field with a Frequency Output
Authors: Osadchuk V. S. , Osadchuk A. V.
Published: December 2011

In the given article the integrated circuits of transducers of a magnetic field in which magnetic sensitive transistors act in a role of active elements of autogenerating arrangements of transducers that simplifies circuits of sensor controls of a magnetic field are offered. It is shown, that for the complete embodying transducers in an integrated view the passive tuned-circuit inductance of the arrangement is implemented as the reactive transistor. The greatest sensitivity which changes from 7,2 kHz/mT up to 6,3 kHz/mT , the circuit design about a magnet a sensing element has on the basis of two collector bipolar transistors with the active inductive element. Ill. 9, bibl. 7 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.289
Fractional Calculus in Modelling of Measuring Transducers
Authors: Luft M. , Cioc R. , Pietruszczak D.
Published: December 2011

The paper is inspired by developments of fractional calculus in areas of control theory and electrical measurements. It outlines an example of modelling the measuring transducers with the use of this calculus. The algorithm determining these models is presented in the form of a fractional calculus notation and then the models are compared to the ones described by means of classical differential equations. Tests are executed in the Matlab/Simulink programme. Ill. 6, bibl. 7 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.297
Voice-based Human-Machine Interaction Modeling for Automated Information Services
Authors: Maskeliunas R. , Ratkevicius K. , Rudzionis V.
Published: December 2011

Voice based human-machine dialogs are becoming more and more important part of informative services. The implementation of voice dialogs enables to realize some of the aims of telecommunication services more successfully and efficiently. The main aim is to enable the communication according the principle "anytime-anywhere". The importance of voice dialogs is also caused by the fact that principle "anytime-anywhere" often could be realized only using mobile and portable devices. Those devices typically have small keyboards and screens and hence voice based interface has advantages over traditional keyboard and screen based interface. The paper presents the model of multimodal interface which core element is the recognition of voice commands. The model targets the informative services provided by the Lithuanian medical and social security enterprises. Paper shows that recognition accuracy of Lithuanian voice commands could be increased significantly if the foreign language which has closer to Lithuanian phonetic structure engine is adapted. Ill. 2, bibl. 11, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.300
Efficient ECG Modeling using Polynomial Functions
Authors: Jokic S. , Delic V. , Peric Z. , Krco S. , Sakac D.
Published: December 2011

An efficient ECG modeling algorithm is presented in this paper. The model is based on fitting polynomial functions to real ECG. This algorithm describes a segmentation of a heartbeat and fitting an appropriate polynomial function to the segments. The model performances are evaluated in terms of PRD, preserve of ST-T segment clinical information and the execution time. When comparing this model with the existing one, the PRD improvements can be seen, especially in those signals with high morphological diversity heartbeats. Moreover, the computing time is significantly reduced. Using appropriate model features, ST-T analysis achieves an average accuracy of more than 94%. The obtained data shows that this model is applicable to other ECG processing like: heartbeat analysis, compression and filtering. Ill. 2, bibl. 9, tabl. 3 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.304
Electrodynamical Investigation of the Photonic Waveguide Structure
Authors: Gric T. , Nickelson L.
Published: December 2011

Presented the electro dynamical analysis of the n-Si photonic waveguide structures. The rigorous solution of the problem was fulfilled by the Singular Integral Equations' method (SIE) using the Muller's method. Here the dispersion characteristics of six different structures with three, five and seven air holes are analyzed. The air holes are located symmetrically to the centre of the waveguide substrate in the first three structures. The air holes are shifted in the other examined structures. In the article dependencies of the phase constants and losses on the number of holes and their location with respect to the top and the bottom sides of the semiconductor substrate are presented. The dispersion characteristics' comparison of waveguides with the different location of holes inside n-Si substrate shows that especially strong dependences are observed in the behaviour of losses. Ill. 5, bibl. 9 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.344
Autonomous System for Observation of QoS in Telecommunications Networks
Authors: Kajackas A. , Batkauskas V. , Saltis A. , Gursnys D.
Published: December 2011

A project of creation of a multi-dimension and autonomous QoS evaluation and monitoring system is presented in the paper. The initial data for evaluation of the QoS is collected from users using specially created software programs - iQoS modules. Singularities of the initial data collection are discussed. Test results of the prototype system are presented. Ill. 2, bibl. 14 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.347
Experimental Research of Wireless Sensor Network Application in Aviation
Authors: Stankunas J. , Rudinskas D. , Lasauskas E.
Published: December 2011

The paper presents the application of wireless sensor networks in aviation for measuring and transferring flight parameters. IEEE 802.15.4 standard ZigBee of low price, which operates in the low range of the ISM frequency band, was chosen. Experiments were performed during free flight. Evaluation of measurement results using Kalman filtering algorithm is provided. Ill. 6, bibl. 10, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.353
Analysis of Switching Conditions of IGBTs in Modified Sine Wave qZSIs Operated with Different Shoot-Through Control Methods
Authors: Vinnikov D. , Roasto I. , Zakis J. , Ott S. , Jalakas T.
Published: December 2011

This paper discusses two novel shoot-through control methods specially developed for the modified sine wave qZSI -the pulse width and phase shift modulation. The operating conditions of IGBTs are experimentally examined in both control methods and the resulting advantages of each method are explained. Ill. 16, bibl. 6, tabl. 6 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.354
Accuracy of Electronic Devices Efficiency Evaluation
Authors: Eidukas D. , Stupak V.
Published: December 2011

Electronic devices are considered. In an interval between inspections periodic controls of serviceability are stipulated. The method of definition of accuracy of evaluation of efficiency index of devices is offered. Accuracy is characterized by an error caused by likelihood properties of parameters, influencing an index of efficiency. Error is defined by means of the computing experiment based on a method of statistical modeling. During experiment, 1000 realizations are received. Parameters influencing an index of efficiency are presented by random variables distributed under the rectangular law. Data of computing experiment show that half of width of confidential intervals 99 percent for an index of efficiency does not exceed 0.05 % (of size of a sample mean). Values of factor of variation do not exceed 0.60 %, and the error of evaluation of efficiency index does not exceed 1.80 % (of size of a sample mean). Ill. 1, bibl. 9, tabl. 1 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.355
Fast Earth Fault Location by Analysing the Character of the Initial Processes
Authors: Gudzius S. , Karaliute U. , Markevicius L. A. , Morkvenas A. , Miliune R.
Published: December 2011

Nowadays it is thought that distribution power networks have the ability to isolate damaged power network place by making optimal links, to identify the fault character, to recognize the character of transients, to establish the fault cause and estimate the state of electrical equipment. For such an objective, fast identification of the earth fault and its place location is a very important problem which requires reliable solutions. The paper describes the new algorithm of earth fault detection and location which is based on the analysis of the initial processes of the fault and its keystone elements. The earth fault detection and location algorithm has been implemented in distribution network state identification terminals. Ill. 6, bibl. 11 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.356
Investigation of Time and Energy Consumption using the Physical Model
Authors: Baums A. , Gordjusins A. , Kanonirs G.
Published: December 2011

Different machine vision, image analysis systems and navigation sensor modules were tested during the physical model development, the most conformable was selected. Different route planning algorithms were implemented and analyzed. The best result is obtained using the Ant-colony algorithm. The physical model is used for an autonomous outdoor mobile robot software development and student education. Ill. 3, bibl. 5 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.363
Transient Analysis and Modelling of 2nd- and 4th-Order LCLC Filter under Non-Symmetrical Control
Authors: Dobrucky B. , Benova M. , Kascak S.
Published: December 2011

The paper shows how it is possible to obtain the harmonic sinusoidal voltage on the load side at non-harmonic periodical supplying from the converters. It can be used either LCLC resonant filter for frequency of fundamental harmonic component, or LC filter tuned for switching frequency. Both filters have to remove higher harmonic components from the supplying voltage to reach the harmonic distortion roughly 5 %. The paper deals mainly with analysis and modelling of 4th order LCLC filter (of the first type) under non-symmetrical supply and with comparing to the other types of filtering. Simulation results as well as experimental verification confirm good quality of output quantities of the filter. Ill. 19, bibl. 10 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.364
Energy Sub-Metering Data Acquisition System
Authors: Bulbenkiene V. , Pecko A. , Zulkas E. , Kuprinavicius A. , Sokolov A. , Mumgaudis G.
Published: December 2011

This paper describes the creation of a system that acquires building energy sub-metering data. The system is designed in a way that allows it to use different sensors for different energy resources sub-metering. A wireless communication standard that allows to achieve the best combination of communication range, low power sub-metering and to give the system more flexibility is chosen. This paper shows how electrical energy sub-metering data is extracted by the sensor node from the current wire without any physical invasion and wirelessly passed to the concentrator. Non-standard error processing solutions and their application to the prototype, and issue-specific solutions related to energy transmission and processing using standard wired and wireless transmission protocols are analyzed. Ill. 4, bibl. 8 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.366
Influence of Supply Current to the Characteristics of Reactive Oscillating Motors
Authors: Brazaitis A. , Guseinoviene E.
Published: December 2011

Two tasks were solved in this article. It is proven that partition of synchronous reactive oscillating motors to reactive oscillating motors and pulsating current ones is baseless, since some of their behavior features and working characteristics are different only because of different supply currents. It is offered to deny this partition and supply sources and drives of these motors to call alternating current drives and pulsating current drives. The second task - square of motors' current is treated as dependent variable and called the converted current. This abstract variable allows to take a look at these motors deeper and visually. Ill. 1, bibl. 5, tabl. 3 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.370
Computer Restoration of 2D Medical Diagnostic Signals with Noise Frequency Spectrum
Authors: Nikolova M. , Dimitrova Tz.
Published: December 2011

An application of mathematical method of Aisenberg for restoration of low frequency medical diagnostic signals after influence of noise is described in the paper. The restoration of frequency spectrum of medical diagnostic signals has been done after preliminary analyses of frequency spectrum of signals with noise and disposition of frequency band of noise in the frequency band of information signals. Some experimental results obtained on the base of application of Aisenberg's method for restoration of medical diagnostic signals are described in the paper. Ill. 9, bibl. 8 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.374