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1

A multi-criteria optimisation method for laser welding of austenitic steel 904L

Nasiłowska B., Pszczółkowski J., Bogdanowicz Z., Bożek M.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 76, nr 2

72--84

EN

Purpose: Due to the increasing requirements for improvement of the welded structures quality, it is necessary to analyze the welding process in the design phase. In this context a system of criteria for optimization was introduced. This system is based on the integrated computational tools which allow specifying the function for the selection of the parameters of the welding process without the expensive experiments. Design/methodology/approach: The analysed independent variables were as follows: type of welding head (monofocal and bifocal), laser beam power (P) and laser beam travel (welding) speed (v). The following results were selected as the criteria of weld quality assessment: visual assessment of weld and root reinforcement, metallographic assessment of horizontal microsections, microhardness tests, shape factor determined using Jewdokimow and Lawrence methods, and the stress concentration factor. The weld cross-section shape factor was also used as a criterion. An objective function specifying the quality of weld was determined as the sum of point grades given for each of the above assessment criteria. Optimum values of the parameters for laser welding of 904L austenitic steel were determined using MatLab software while taking into account the values of the objective function,. After verifying the experimental results, the following parameters were identified for optimum laser welding of steel: laser beam power and speed of welding with a monofocal head. Findings: The range of the selected technological parameters, ie. head type, power and speed of the laser beam allowed to adjust optimal welding parameters based on the visual and destructive experiments, ie .: P = 4.5 kW, v = 1.4 m/min. Due to the lower defectiveness of the welded joints monofocal head was chosen. Research limitations/implications: This article presents the optimization procedure for the parameters of the laser welding of flat elements with a thickness of 5 mm made of steel 904L. Originality/value: This paper presents a procedure for configuring parameters for laser welding of steel using a multi-criteria optimization method for austenitic steel 904 L laser beam welding.

2

Some aspects of Intelligent Transport System auditing

Bazan M., Bożek M., Ciskowski P., Halawa K., Janiczek T., Kozaczewski P., Rusiecki A.

Archives of Transport System Telematics

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2015

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Vol. 8, iss. 3

3--8

EN

Nowadays, in urbanized areas one of the most important matters is to determine a priori the time of driving from one zone of the city to another at various times of the day. The problem of travel time prediction is crucial in Intelligent Transportation Systems. The solution to this problem is a foundation of any route guidance system that will redirect drivers to their target destination via routes that have a lighter traffic load and thus higher travel velocity. In this paper is present a concept of a statistical methodology, developed by the ArsNumerica Group, that enables a quantity audit a travel time prediction algorithm. The methodology assumes that we are given database records of vehicles recognized by their unique identifier as well as duration times for which the messages with the predicted travel time are displayed VMS. the second aspect of ITS auditing considered in this paper is a placement of video cameras to measure vehicle stream velocity. Inappropriate camera location results in the fact that the stream velocity measured by them has a low usefulness for travel time prediction.

3

Nieskuteczność kontroli końcowej przyczyną niskiej efektywności procesu wytwarzania

Bożek M., Rogalewicz M.

Inżynieria Maszyn

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2013

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R. 18, z. 1

84--96

PL

Artykuł podejmuje problem wpływu niewłaściwie zaplanowanej kontroli jakości na efektywność procesu wytwarzania. Na przykładzie wybranego narzędzia chirurgicznego opisano i wyznaczono wartości wybranych wskaźników skuteczności i efektywności jakościowej procesu oraz skuteczności procesu kontroli. Pokazano, że w niektórych przypadkach umiejscowienie kontroli w końcowym etapie procesu produkcji może prowadzić do drastycznego obniżenia efektywności procesu.

EN

The article deals with the problem of an influence of incorrectly planned quality inspection on the efficiency of the manufacturing process. On the example of chosen surgical instrument, values of chosen quality process efficiency and effectiveness indices and quality inspection effectiveness index were described and computed. It was shown that in some cases placing a quality inspection at the end of production process can lead to a drastic decrease of the process efficiency.

4

Spoina w trójwymiarze. Techniki badań ultradźwiękowych "Phased Array" dla badania spoin na rurach o grubości poniżej 8 mm

Bożek M., Wiliński S.

Energetyka Cieplna i Zawodowa

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2013

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Nr 6

101--107

PL

Jakie korzyści wynikają z zastosowania głowic wieloprzetwornikowych przy badaniu metodą ultradźwiekową spoin na rurach o grubości poniżej 8 mm? Przede wszystkim umożliwiają ocenę wielkości wykrytej wady i jej orientacji w sposób mniej czasochłonny i bardziej przyjazny dla operatora. Bardzo ważną cechą tej metody jest też możliwość zapisu w postaci cyfrowej wszystkich zobrazowań danej spoiny i w konsekwencji wizualizacji wykrytych wskazań w trójwymiarze.

5

Adaptacyjne zabezpieczenie odległościowe linii dwutorowych dla zwarć z udziałem ziemi

Iżykowski J., Bożek M.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9a

22-26

PL

W artykule przedstawiono adaptacyjny pomiar impedancji pętli zwarciowej dla zabezpieczenia odległościowego linii dwutorowej. Adaptację wprowadzono dla zwarć jedno- i dwu-fazowych z udziałem ziemi. Na podstawie analizy uogólnionego modelu pętli zwarciowej oraz warunków granicznych rozważanych zwarć uzyskano zwartą postać na impedancję pętli zwarciowej. Zapewniono przy tym skompensowanie błędu pomiaru impedancji pętli zwarciowej od rezystancji przejścia. Przedstawiono wybrane wyniki badań opracowanego algorytmu pomiarowego.

EN

In this paper an adaptive measurement of fault-loop impedance for distance protection of a double-circuit line is presented. Adaptation is applied for single- and double-phase faults involving earth. On the base of analysis of a generalized fault-loop model and constrains for considered faults the compact formula for a fault-loop impedance was obtained. Compensation for an error resulting from a fault resistance was assured. Sample results of evaluation of the developed measurement algorithm are included.

6

Zarządzanie jakością w stacjach dializ w Polsce

Handzelewicz A., Skrzypczyńska K., Bożek M.

Problemy Jakości

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2012

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R. 44, nr 10

24-29

7

Determinanty efektywnego wdrożenia filozofii LEAN MAUFACTURING

Bożek M., Handzelewicz A.

Problemy Jakości

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2012

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R. 44, nr 1

13-20

PL

Artykuł ma na celu wskazanie wybranych determinantów efektywnego wdrożenia filozofii Lean Manufacturing (LM) w przedsiębiorstwach produkcyjnych. Opierając się na definicji LM zaprezentowano cztery czynniki, które mają największy wpływ na skuteczność implementacji nowego podejścia w zarządzaniu produkcją. Te czynniki to: dobór odpowiedniego modelu zarządzania zmianą, praca zespołowa, wdrożenie jednolitego systemu szkoleń stanowiskowych, dostosowanie zasad rachunkowości finansowej i zarządczej do wymagań LM. Każdy z wymienionych wyżej czynników został szczegółowo zdefiniowany wraz z dokonaniem oceny ich oddziaływania na skracanie czasu między złożeniem zamówienia przez klienta a wysyłką towaru do końcowego odbiorcy poprzez eliminowanie marnotrawstwa ze strumienia wartości.

EN

The aim of the paper is presenting chosen determinant of effective implementation of the concept of (LM) in a manufacturing company. Basing on the definition of Lean Manufacturing it presents four factors which influence the effectiveness of the tool most. The factors are: the choice of a proper model for managing the shifts, team work, implementing consistent system of workstation training, and lastly adjusting accounting rules to the requirements of LM.

8

Analysis of efficiency of Lean Manufacturing and Six Sigma in a production enterprise

Bożek M., Hamrol A.

Management and Production Engineering Review

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2012

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Vol. 3, No. 4

14-25

EN

The aim of the paper is to identify, on the basis of selected examples, the effectiveness of Lean Manufacturing (LM) and Six Sigma (SS) techniques in a large-production enterprise characterized by low-volume production, a wide product range, stabilized manufacturing technology and a so-called "brownfield" site. Many scholars have attempted to answer which approach, LM or SS, is more effective in a production enterprise. The authors of the paper aim to answer this question on the basis of a detailed analysis of efficiency of implementation of both techniques. The amount of savings generated from undertaken projects and increase of profitability of the analysed production system have served as performance measurements.

9

Differences in trabecular bone mechanical strength measured by the x-ray microcomputed tomography and compressive test

Binkowski M., John A., Nowak R., Bożek M., Bielecki M.

Journal of Medical Informatics & Technologies

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2010

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Vol. 15

163--168

EN

The article describes the concept of measurement of the mechanical strength of trabecular bone dissected from human femoral head. When the studies are performed based on the human trabecular bone, there is a risk that correlation can be not achieved due to high discrepancy in the distribution of the bone density and mechanical properties. The compressive tests and X-ray microcomputed tomography with associated density phantom were used to deliver quantitative data. There is a conclusion that the selection of the region in the femoral head has to be performed very carefully. The region where cylinder is dissected can influence the results and produce fake data, which could not be correlated in the density of bone.

10

Adaptacyjne zabezpieczenie odległościowe linii dwutorowej w przypadku zmniejszonej dostępności sygnałów pomiarowych

Bożek M., Iżykowski J.

Prace Naukowe Instytutu Energoelektryki Politechniki Wrocławskiej. Studia i Materiały

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2009

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Vol. 98, nr 32

96-107

PL

W referacie zaprezentowano nowe algorytmy decyzyjne zabezpieczenia odległościowego linii dwutorowych, pozwalające na wyeliminowanie wpływu efektu reaktancyjnego na pracę zabezpieczenia. Algorytmy znajdują zastosowanie w przypadku zmniejszonej dostępności sygnałów pomiarowych, a wynikiem ich działania jest przesunięcie charakterystyki rozruchowej zabezpieczenia o składowe wektora przesunięcia. Przyjęto założenia upraszczające, które w przypadku zmniejszonej dostępności sygnałów pomiarowych są konieczne. Zaprezentowane procedury znajdują zastosowanie w przypadku zwarć jednofazowych doziemnych. Rozważono dwa warianty pracy linii dwutorowej - oba tory załączone oraz jeden z torów odłączony i uziemiony na obu końcach. Algorytmy zostały przetestowane z wykorzystaniem danych pochodzących z symulacji wykonanych w programie ATP-EMTP.

EN

The paper presents a new adaptive algorithms for distance protection relay, designated for double circuit line. They allow to compensate for the adverse influence of the reactance effect on decision making process. The proposed procedure is based on moving the relay characteristic according to calculated shift vector components. Limited availability of signals from one end was taken into account and the algorithms were developed for two cases: both lines in operation and one line disconnected and earthed at both ends. Input signals used for testing purposes have been obtained through versatile simulations in ATP-EMTP program.

11

Lokalizacja zwarć przy stosowaniu kompletnych pomiarów z jednego końca linii dwutorowej

Iżykowski J., Rosołowski E., Bożek M.

Automatyka Elektroenergetyczna

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2009

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Nr 1 (62)

4-8

PL

W artykule rozważono stosowanie kompletnych pomiarów z jednego końca dwutorowej linii elektroenergetycznej. Pokazano, że przy tej dostępności sygnałów pomiarowych problem określenia miejsca zwarcia w linii dla celów inspekcyjno-remontowych jest w pełni rozwiązalny i nie trzeba stosować założeń upraszczających. Wykazano, że możliwe jest wprowadzenie adaptacji, zapewniającej całkowite wyeliminowanie niekorzystnego wpływu rezystancji w miejscu zwarcia na działanie zabezpieczenia odległościowego. Podano reprezentatywne przykłady ilustrujące zalety stosowania przedstawionych algorytmów. Artykuł recenzowany.

EN

Use of complete measurements from one end of a double-circuit power line has been considered. It has been shown that under such availability of measurements, an issue of fault location for inspection-repair purposes becomes completely solvable and there is no need for applying simplifying assumptions. It has been proved that it is possible to introduce an adaptation, which assures complete compensation of adverse influence of fault path resistance on operation of distance protection. Representative examples, which illustrate advantages of applying the presented algorithms, have been included.

12

Kompensacja efektu reaktancyjnego dla zabezpieczenia odległościowego przy pełnej dostępności pomiarów z jednego końca linii dwutorowej.

Bożek M., Iżykowski J.

Prace Naukowe Instytutu Energoelektryki Politechniki Wrocławskiej. Studia i Materiały

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2007

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Vol. 97, nr 31

48-59

PL

Przedstawiono adaptacyjny algorytm decyzyjny zabezpieczenia odległościowego linii dwutorowej, który pozwala na skompensowanie negatywnego wpływu efektu reaktancyjnego na podejmowanie decyzji przez zabezpieczenie. Zaproponowana procedura polega na przesuwaniu charakterystyki rozruchowej przekaźnika odległościowego na podstawie wyznaczonych składowych wektora przesunięcia. Założono pełną dostępność sygnałów pomiarowych z jednego końca linii dwutorowej. Opracowany afgorytm zosta/ przetestowany z użyciem sygna/ów uzyskanych z symulacji zwarć przeprowadzonych w programie ATP-EMTP.

EN

The paper presents a new adaptive algorithm for distance protection relay, designated for double circuit line. It allows to compensate for the adverse influence of the reactance effect on decision making process. The proposed procedure is based on moving the relay characteristic according to calculated shift vector components. Complete availability of signals from one end was taken into account. Input values have been obtained through versatile simulations in ATP-EMTP program.

13

Accurate fault location in three-terminal overhead lines using two-end synchronized measurements of voltage and current phasors

Iżykowski J., Bożek M., Moląg R.

Archives of Electrical Engineering

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2007

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Vol. 56, nr 3-4

213-228

EN

This paper deals with fault location in three-terminal overhead lines by means of two-end synchronized measurements. The delivered fault location algorithm consists of three subroutines, designated for locating the faults in particular line section and the procedure of selecting the valid subroutine. All subroutines are formulated for the natural fault loops, which is distinct from the up-to-date approach. This has been applied with the aim of minimising the adverse influence of uncertainty with respect to impedance data of equivalent sources behind the line terminals upon the fault location accuracy. The selected results of fault location accuracy evaluation performed with the use of fault data obtained from ATP-EMTP simulations are presented and discussed.

PL

W artykule rozpatrzono lokalizację zwarć w liniach napowietrznych z odgałęzieniem z użyciem synchronicznych pomiarów na dwóch końcach linii. Przedstawiony algorytm składa się z trzech procedur lokalizacji, przeznaczonych do lokalizacji zwarć w poszczególnych sekcjach linii, oraz procedury wyboru obowiązującej procedury lokalizacji. W odróżnieniu od dotychczas stosowanego podejścia, wszystkie procedury lokalizacji zostały sformułowane dla naturalnych pętli zwarciowych. Zastosowano to w celu ograniczenia niekorzystnego wpływu niepewności danych w odniesieniu do inipedancji ekwiwalentnych podsystemów z końców linii na dokładność lokalizacji. Zamieszczono i omówiono wybrane rezultaty analizy dokładności lokalizacji zwarć, przeprowadzonej z użyciem przebiegów uzyskanych z symulacji zwarć z pomocą programu ATP-EMTP.

14

Współczesny model polskich służb specjalnych. Służby informacyjne czy policyjne?

Bożek M.

Zeszyty Naukowe AON

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2005

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nr 1(58)

92-104

EN

In all publications concerning the secret service two basic models of their functioning are discussed. In the first one the secret service perform mainly the information functions and thus is not equipped with any tools of penal reaction to an event. Even in a situation when in their activities they confirm that a crime has been committed, they do not perform penal investigation but transfer the materials to the prosecutor’s office or police. In the second model the secret service functions include acquiring, analysing and transferring information on threats, as well as recognising and detecting crimes and chasing criminals. The information function is traditionally attributed to intelligence services, whereas mixed solutions are applied in case of counterintelligence services. The investigation (police) function, apart from information function appears in the counterintelligence activities. The task of services that perform this function is to chase people suspected of committing crime that is a special kind of breaching the law. Classic examples of information secret service model are British and German intelligence and counterintelligence services, whereas American and Russian counterintelligence present the mixed solutions’ model where secret service perform both information and police functions. Polish law concerning secret service legal status resemble American and Russian solutions rather than British or German. It cannot be forgotten, however, that also Polish experiences played an important role in forming the secret service legal position. The post-war experiences, where the Polish People's Republic’s security bodies were legally able to conduct penal investigations, are more visible on this background. In the Polish secret service model, binding due to law regulations of 2003 and 2004, ABW - Interior Security Agency is another service that apart from the Police, Border Guard and Military Police is equipped with police function. In the area of detecting and recognising crime, it has trial rights included in the Penal Code. Other Polish secret services - AW - Intelligence Agency and WSI - Military Intelligence Agency are information services that combat threat using operational methods. Therefore, one can claim that the secret service reorganisation conducted in 2002 has not brought any significant changes in the secret service functioning. Due to the same reasons, one can say about a certain continuity in the organisational and functional model of secret service in the last 15 years.

15

Charakter i pozycja prawna polskich służb specjalnych w strukturze aparatu państwa

Bożek M.

Zeszyty Naukowe AON

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2005

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nr 2(59)

143-161

EN

Considering the issue of Polish Special Services legal position requires referring to many specific matters. It is essential to explain the definition of "special services" in the Polish legal system. Firstly, it is necessary to describe what state institutions belong to special services. The analysis of the Polish law shows that the term "special services" is used only in two legal acts. They are: The Law on Internal Security Agency (the ABW) and Intelligence Agency (the AW), passed on the 24th May 2002, and The Law on Military Information Services (the WSI), passed on the 9th July 2003. Other legislation either does not know the term "special services" at all, or it is used in the context of defining the co-operation with institutions that the special services apply to. In the regulations concerning the ABW and the AW the term "special services" is used in article 11 and the following, whereas the act on the WSI uses it in article 1.2. As a consequence of these regulations we can say about the strict list of the Polish Special Services which include only three state institutions: Internal Security Agency, Intelligence Agency and Military Information Services. Such direct pointing in article 11 makes the issue of the special services beyond doubts. Secondly, what seems to have decided of such an approach to the issue of the secret services is the range of tasks which these three institutions are supposed to perform. The objects of the interests of the special services are intelligence and counterintelligence actions. They are reserved only for the ABW, the AW and the WSI. They are not taken by other state organisations dealing with state security such as: Police, Border Guard, Government Protection Bureau and Military Police. The connection between intelligence, counterintelligence and the state security is so obvious that the special treatment of institutions taking this kind of actions should not be a surprise. It is also the first step towards indicating the place of the special services in that part of the legal system that is responsible for providing the state security. The character of these tasks causes more and more noticeable organisational isolation of the special services from the structure of the State. These services, on ground of legislation of 2002 and 2003, are still dependent of constitutional executive authorities. But the situation of the ABW and the AW has profoundly changed. Since 2002, these two institutions have been subordinated to the Prime Minister. They are led by the Chiefs of the ABW and the AW, who are directly subordinate to the Prime Minister. The WSI is supervised by the National Defence Minister, as it has been to date. What changed in 2002 is the fact that the positions of the ABW and the AW chiefs were established instead of the Minister Co-ordinator for Special Services. The rule is that these Services are led by the Chiefs who are not officers but civilians. That last change influences the character of the ABW and the AW as the civil special services. On the one hand, their tasks and activity have to be apolitical. On the other hand, the civil status of their chiefs gives an opportunity to fill these positions by members of political parties. Obviously, the fact that they are staffed by politicians does not have to mean that the Services are political. The transparency of the system is important. This regulation is open to doubt as far as the constitutional rule of the parliament is concerned. The point of this rule is the government's answerability to the Parliament. The government is a creation of a party or a coalition having a majority to support the government. Members of the government are also answerable to the Parliament individually. Consequently, the Parliament has the power to react up immediately to every minister's actions. However, the Parliament cannot apply that towards the Chiefs of the ABW and the AW because they are not members of the government formally, despite the fact that their factual status is basically not different from the position of any minister who is not in charge of a particular government department.