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This paper presents some structured trellises for the optimal [36, 13, 12] code, which reach the upper bound on maximal code-distance in [1]. It was found in [2] using Kasahara et al. construction [3]. This method of construction supports constructions of structured trellises for the code using the approach presented in [4]. The practical importance for wireless communications and SDR is that knowledge...
The paper elaborates on the design of an empirically tested pedagogical framework for e-Learning, covering pedagogies which underpin the subject matter in everyday learning environment as well as the ways in which learning material is delivered and assessed. Designed framework presents an essential part of UNITE e-Learning system conceptualization and development. Five-component pedagogical framework...
This paper presents selected methods in angular rotor speed estimation for induction motor drives. Modern control schemes for high-performance drives (e.g. Field Oriented Control, Direct Torque Control) are based on precise knowledge of some physical quantities that are hard to measure or are immeasurable in standard machine (e.g. fluxes). Other quantities needed for control require additional transducers...
This paper presents some of the design decisions that had to be taken and solutions that were adopted during the development of a compiler for a subset of Object Pascal programming language. The compiler is part of a project that has the purpose of facilitating the rapid development of Palm OS applications. The paper details the structure and functions of the compiler's components. The final part...
In this paper we present a novel technique in which the Maxwell equations, discretized by the Transmission Line Method in a three-dimensional domain, are coupled to the Schroedinger equation and simultaneously solved. The goal is to develop a method that accounts for deterministic electromagnetic field dynamics together with the quantum phenomena, which are typical of nanotube transistor devices....
We present a scalable method for efficient implementation of matrix formulation for finite difference time domain (FDTD) algorithm on parallel architectures. The matrix definition based on physical data properties and data division among grid nodes yielding minimal data transfer between them is described. Numerical performance is evaluated in the heterogeneous grid environment and two clusters.
Power consumption has become an important concern when it comes to the implementation phase of wireless devices. Especially, in mobile phones, where design characteristics like size and weight are forbidden the use of large batteries, minimizing power loss is quite challenging. In this paper, power issues of new generation's cellular phones have been explored in detail, at a system level. The study...
In this paper is presented the analyze of the atmospheric perturbations on the high voltage (HV) lines. Because we deal with high -frequency electromagnetic pulses, the HV line parameters are modeled using the Transmission Line Method (TLM). Imperfect ground present is included in model. In this case imperfect ground is modeled as return path. The computation module allows the geometrically necessary...
This paper compares algorithms used for control of super-conducting cavities in the FLASH accelerator and laser in DESY Research Center (Hamburg, Germany), and describes features of the adaptive feed-forward algorithm. Described solution was implemented in the PowerPC 405 processor embedded in the Xilinx Virtex II Pro FPGA circuit.
The paper presents a computer controlled platform that authors devised and built for testing electrical machines both in laboratory and in industrial environments. The hardware and software architecture of the system were developed to address the testing specifications required by standards or requested by customers. Also, the results of several significant measurements that were performed with this...
In this paper, a fuzzy logic congestion control algorithm which combines the merits of the explicit congestion notification (ECN) and the backward explicit congestion notification (BECN) mechanisms is implemented in a satellite TCP/IP network environment. A roundtrip time (RTT) based decay function is proposed in order to reduce the amount of reverse traffic. This algorithm is compared with the basic...
Although there are certain "preferred" languages for real-time system design, such as C, C++, Ada 95, and increasingly Java, many real-time systems are still written in Fortran, assembly language, and even Visual BASIC. The purpose of this article is to synthesize the theoretical basis of real-time distributed systems in order to facilitate the definition and implementation a new programming...
This paper considers power characteristics of the electric energy generating system of an alternating current "variable speed - constant frequency". The system has "the permanent magnet synchronous generator - the voltage-source inverter (VSI1) - the voltage-source inverter (VSI2)". VSI1 is synchronous rectifier, for control VSI1 use three - phase PWM. Algorithms of control by...
The architecture for the transform domain transcoder from MPEG-2 Video to MPEG-4 AVC is presented in the paper. The possible solutions for main components of the transcoder are analysed. The modification of the algorithm for compensation of the drift caused by the different half-pixel samples interpolation methods used in MPEG-2 Video and MPEG-4 AVC/H.264 is also proposed.
The aim of this work is to analyze the viability of using co-simulation tools in the electrical machine design process. Coupling among different simulation domains such as thermal, electromagnetic, electric or mechanical permits to optimize the machine design before a prototype is built. A conventional electric machine design consists in two steps: an initial analytic design is complemented by a more...
Electrical power system engineers often face a challenge of modeling power system components and performing complex calculations. This paper describes a teaching/learning process of modeling power systems networks and performing network calculations in an object-oriented environment.
Oil field asset owners and operators face two primary issues in exploration and production; asset productivity and operating efficiency. Typically, operators do not have visibility to sense the current state of the oil field and respond with actions to reduce well down-time or increase the oil flow. These sense-and-respond capabilities have been limited by the remoteness of this "first mile"...
In this paper, we address the problem of missing values in input datasets of user modeling algorithms. The origin of these missing values is not a typical one as known in general statistics, but a combination of a so called "cold start problem" and the fact that one user typically gives ratings to only a relatively small number of content items. The ratio of missing values can be extremely...
Medical diagnosis and prognosis is an emblematic example for classification problems. Machine learning could provide invaluable support for automatically inferring diagnostic rules from descriptions of past cases, making the diagnosis process more objective and reliable. Since the problem involves both test and misclassification costs, we have analyzed ICET, the most prominent approach in the literature...
The multiregion FDM method is applied to the two tube electrostatic lens providing accurate and precise potential calculations for this geometry. It is shown that the multi region structure necessary for these calculations can be adaptively established in software and that the limitations of a cumulative or round off error can be overcome by the use of high precision arithmetic. Finally a comparison...
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