Wyniki wyszukiwania - BazTech

1

Straty mocy w liniach kablowych wysokiego napięcia

Pasierbek Artur

Przegląd Elektrotechniczny

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2022

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R. 98, nr 11

215--217

PL

W artykule przedstawiono metodę wyznaczani strat mocy w kablach energetycznych wysokiego napięcia modelowanych fazowo, dla dowolnej konfiguracji kabli (układ płaski, trójkątny, mieszany, dowolny). Uwzględniono układ pracy z jednostronnym (SPB) i dwustronnym (BE) uziemieniem ekranów. W opracowanym modeli i bazującym na nim oprogramowaniu do analizy strat mocy uwzględniono przeplatanie przewodów roboczych lub ich ekranów oraz możliwość występowania przewodów ECC w konfiguracji SPB i BE.

EN

The article presents a method of determining power losses in phase-modeled high-voltage power cables, for any cable configuration (flat, triangular, mixed, arbitrary). A system of work with single point bonding (SPB) and both-ends bonding (BE) of shield grounding is included. In the developed models and the software based on it for the analysis of power losses, the interlacing of working conductors or their screens and the possibility of the presence of Earth Continuity Conductor (ECC) cables in SPB and BE configurations were taken into account.

2

Design of high efficiency, low noise power supply for automotive audio systems

Morgos Jan, Frivaldsky Michal, Hanko Branislav

Przegląd Elektrotechniczny

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2021

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R. 97, nr 1

100--104

EN

The paper deals with proposal and simulations of the high efficiency and high-power switching power supply suited for hi-fi audio amplifiers in automotive applications. Main focus is given on specific requirements, which are needed in the automotive segment, low voltage input must be considered. The presented article describes design of the main topology and its parameters. Key operational characteristics are very high efficiency in full spectrum of operation and high-power density. The performance of proposed design is condition by high-current operation, thus thermal management is key indicator related to requirements on high-efficiency operation. Secondary features of proposed converter must consider high-end requirements of audio systems, which are fast dynamics to load change and low noise of output voltage. Almost switched-mode power supplies are defined by high noise of the output voltage, presented approach proposes also solution of the low noise output filter.

PL

Zaprezentowano projekt wysokiej jakości i mocy układ zasilania wzmacniacza hifi w zastosowaniu do samochodów. Ze względu na duży pobór prądu zadbano w właściwości termiczne układu. Zadbano też o mały poziom szumów.

3

Invariant Structures and Dependence Relations

Janicki R., Kleijn J., Koutny M., Mikulski Ł.

Fundamenta Informaticae

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2017

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Vol. 155, nr 1/2

1--29

EN

A step trace is an equivalence class of step sequences which can be thought of as different observations of the same underlying concurrent history. Equivalence is determined on basis of a step alphabet that describes the relations between events in terms of potential simultaneity and sequentialisability. Step traces cannot be represented by standard partial orders, but require so-called invariant structures, extended order structures that capture the phenomena of mutual exclusion and weak causality. In this paper, we present an effective way of deciding whether an invariant structure represents a step trace over a given step alphabet. We also describe a method by which one can check whether a given invariant structure can represent a step trace over any step alphabet. Moreover, if the answer is positive, the method provides a suitable step alphabet.

4

Alphabets of Acyclic Invariant Structures

Janicki R., Kleijn J., Koutny M., Mikulski Ł.

Fundamenta Informaticae

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2017

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Vol. 154, nr 1/4

207--224

EN

A step trace is an equivalence class of step sequences, where the equivalence is determined by dependencies between pairs of actions expressed as potential simultaneity and sequentialisability. Step traces can be represented by invariant structures with two relations: mutual exclusion and (possibly cyclic) weak causality. An important issue concerning invariant structures is to decide whether an invariant structure represents a step trace over a given step alphabet. For the general case this problem has been solved and an effective decision procedure has been proposed. In this paper, we restrict the class of order structures being considered with the aim of achieving a better characterisation. Requiring that the weak causality relation is acyclic, makes it possible to solve the problem in a purely local way, by considering pairs of events, rather than whole structures.

5

Characterising Concurrent Histories

Janicki R., Kleijn J., Koutny M., Mikulski Ł.

Fundamenta Informaticae

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2015

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Vol. 139, nr 1

21--42

EN

Non-interleaving semantics of concurrent systems is often expressed using posets, where causally related events are ordered and concurrent events are unordered. Each causal poset describes a unique concurrent history, i.e., a set of executions, expressed as sequences or step sequences, that are consistent with it. Moreover, a poset captures all precedence-based invariant relationships between the events in the executions belonging to its concurrent history. However, concurrent histories in general may be too intricate to be described solely in terms of causal posets. In this paper, we introduce and investigate generalised mutex order structures which can capture the invariant causal relationships in any concurrent history consisting of step sequence executions. Each such structure comprises two relations, viz. interleaving/mutex and weak causality. As our main result we prove that each generalised mutex order structure is the intersection of the step sequence executions which are consistent with it.

6

Regulacja nadmiarowości przy zapisie danych na nośnikach optycznych

Gołofit K., Rybczyński M.

Elektronika : konstrukcje, technologie, zastosowania

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2009

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Vol. 50, nr 10

95-99

PL

Artykuł wpisuje się w poszukiwania metod archiwizacji dających możliwość zapewnienia wysokiego poziomu bezpieczeństwa danych przy akceptowalnych kosztach. Celem pracy jest wyeliminowanie podstawowego problemu związanego z przechowywaniem informacji na nośnikach optycznych, jakim jest słaba odporność na błędy. Analiza uszkodzeń nośników w połączeniu z konstrukcją mechanizmów korekcji wbudowanej dają obraz rozkładu i charakteru typowych błędów występujących na płytach. Zastosowanie odpowiednich metod kodowania nadmiarowego, przeplotu, rozpraszania i kompresji danych minimalizuje ryzyko utraty danych niezależnie od rodzaju pojawiających się błędów. Rezultatem badań jest system, który z jednej strony umożliwia archiwizację z regulowaną nadmiarowością (np. w zależności od wartości danych), z drugiej strony daje możliwość sprawdzenia stanu zaawansowania zniszczeń i oceny bezpieczeństwa archiwum.

EN

This paper explores archivization methods that can provide high level of data security on optical storage media. The aim of this work is to eliminate major weaknesses concerning optical media. Analysis of erroneous media in combination with error-correcting mechanisms shows distribution and type of errors typically observed on CDs and DVDs, As a result, an adequate error-correcting technique is chosen from the available ones (block, convolutional and others). The risk of data loss is minimized, regardless of error types, by using data formatting methods, compression and coding tools, interleaving and data dispersion. As a result of these studies, an archivizalion system with regulated redundancy is proposed and implemented. One of the main features of this implementation is the method of archive condition verification and estimation of its safety.