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2
Content available remote Udział Politechniki Warszawskiej w odbudowie polski po zaborach (część I)
PL
W artykule (część I) przedstawiono tło historyczne i okoliczności powstania w Warszawie wyższej uczelni technicznej – Politechniki, z językiem wykładowym polskim. Nacisk położono na często nieznane dotąd działania organizacyjne przedstawicieli ówczesnych elit kulturalnych oraz nielicznej wówczas grupy elektrotechników polskich. Dzięki ich ogromnej energii i zaangażowaniu mogło dojść nie tylko do odzyskania niepodległości, ale także budowy od podstaw wielu instytucji państwowych. Zatrudniani w nich byli najlepsi specjaliści gospodarczy oraz naukowcy. Te osiągnięcia nie byłyby możliwe bez także korzystnej sytuacji politycznej w Europie w drugiej dekadzie XX wieku. Heroizm i bohaterstwo ówczesnych patriotów przyniosło sukces, z którego dobrodziejstw do dziś czerpiemy. W części drugiej przedstawione zostaną zasługi poszczególnych pracowników naukowych i technicznych Politechniki Warszawskiej, zwłaszcza Wydziału Elektrycznego, w odzyskaniu niepodległości, a następnie w budowie odrodzonego państwa.
EN
The article (part one) presents historical background and the origins of a university of technology in the city of Warsaw – Polytechnic, where the lectures were given in Polish. It emphasises usually-unknown organisational actions of representatives of the then cultural elite and at the time narrow group of Polish electrotechnicians. It was due to their enormous potential and involvement that Poland not only regained independence but many state-run institutions could be established, hiring highly professional scientists and economists. The achievements would be impossible, however, if not for the favourable political situation in Europe in 1920s. The heroism and valour of the patriots of that time led to the success that has been bearing fruit ever after.
EN
Previous studies have demonstrated that, the length of the lumbar spine is decreasing with age. Despite considerable research based on sagittal measurements, little is known about the changes in the volume of vertebrae. The objective of this study was to evaluate the changes in the volume of either column of the spine with age. Materials and methods: Computed tomography scans of 62 asymptomatic subjects, performed for thoracolumbar trauma evaluation were used to create virtual 3D models. At least 10 patients were assigned to every decade of life from third to eight. We used a novel technique to measure the volume of anterior column (AC) and posterior column (PC) per each segment (a total of 310 segments). Midline sagittal images were used to measure disc height (DH) and vertebral body height (VH). Results: With age, both DH increases, whereas the VH decreases. The overall length of lumbar segment of the spine decreases with age. The volumetric measurements performed on same subjects showed that volume of both AC and PC does not change with age in females. In males, there is a weak but statistically significant correlation between AC volume and age and no change in the volume of PC. The ratio of PC:AC volume does not change with age in women, although it decreases slightly but significantly (in favor of AC) with age in males. Conclusions: The overall length of lumbar spine decreases with age. This process is not a result of mere changes in the volume of either AC or PC.
4
Content available remote Niełatwe początki Wydziału Elektrycznego Politechniki Warszawskiej
PL
W artykule przedstawiono tło historyczne i okoliczności powstania w Warszawie pierwszego w Polsce wydziału elektrycznego - wcześniej działały tylko bowiem katedry elektrotechniczne na Politechnice Lwowskiej. Nacisk położono na często nieznane dotąd działania organizacyjne przedstawicieli ówczesnych elit kulturalnych oraz nielicznej wówczas grupy elektrotechników polskich. Dzięki ich ogromnej energii i zaangażowaniu mogło dojść, mimo przeciwności i kłopotów, do rozpoczęcia najpierw nauczania przedmiotów z dziedziny elektrotechniki w języku rosyjskim, a następnie, po zakończeniu pierwszej wojny światowej – w języku polskim. Starania znakomitych naukowców, m.in.: Mieczysława Pożaryskiego, Kazimierza Drewnowskiego, Stanisława Patschke, Leona Staniewicza, Konstantego Żórawskiego, Stanisława Odrowąża-Wysockiego, Janusza Groszkowskiego i wielu innych sprawiły, że od 14 czerwca roku 1921 rozpoczął pracę dydaktyczna i naukową, jako samodzielna instytucja, Wydział Elektrotechniczny Politechniki Warszawskiej.
EN
The article presents historical background and the origins of the Polish first faculty of electrical engineering that was funded in Warsaw – the older faculties had been operating exclusively in Lviv University of Technology. It emphasises usually-unknown organisational actions of representatives of the then cultural elite and at the time narrow group of Polish electrotechnicians. Despite adversities due to their enormous potential and involvement, it was possible to begin to teach subjects of electrotechnics – at first in Russian and later on after the Second World War was over, in Polish. Effort of splendid scientists such as Mieczysław Pożaryski, Kazimierz Drewnowski, Stanisław Patschke, Leon Staniewicz, Konstanty Żórawski, Stanisław Odrowąż-Wysocki, Janusz Groszkowski, and many more enabled founding on 14 July in 1921 Faculty of Electrotechnology at the Warsaw University of Technology that, as an independent institution, has been providing teaching and research.
5
Content available remote Profesor Władysław Latek – wybitny ekspert maszyn elektrycznych
PL
Dwie wiodące organizacje zawodowe - Stowarzyszenie Elektryków Polskich oraz Polskie Towarzystwo Elektrotechniki Teoretycznej i Stosowanej uznało rok 2016 ROKIEM PROFESORA WŁADYSŁAWA LATKA. Profesor był twórcą ośrodka naukowo-badawczego, zajmującego się projektowaniem, analizą stanów ustalonych i przejściowych oraz eksploatacją maszyn prądu przemiennego dużych mocy, zwłaszcza turbogeneratorów. Był autorem dzieł naukowych, ważnych opracowań dla przemysłu oraz cennych monografii i podręczników. Pełnił funkcję prodziekana i dziekana Wydziału Elektrycznego Politechniki Warszawskiej. Bardzo głęboko angażował się społecznie, został członkiem honorowym SEP i PTETiS. Władysław Latek w roku 1965 zorganizował pierwszą konferencję poświęconą maszynom elektrycznym, która od tego czasu jest nieprzerwanie co rok organizowana przez kolejne polskie politechniki i nosi nazwę: Międzynarodowe Sympozjum Maszyn Elektrycznych SME. Profesor Latek był znakomitym nauczycielem akademickim, pod jego opieką, jako promotora, uzyskało doktoraty 20 studentów. Wielu byłych wychowanków Profesora zajmuje dziś stanowiska profesorskie oraz wypełnia odpowiedzialne zadania w przemyśle, energetyce i administracji gospodarczej.
EN
Year 2016 has been recognized as THE YEAR OF PROFESSOR WŁADYSŁAW LATEK by the Polish Society of Theoretical and Applied Electrical Engineering and the Association of Polish Electrical Engineers. Professor Latek was a founder of a research and development center for designing and analysis of steady and transient states as well as exploitation of high power alternating current (AC) machines, especially turbo generators. He was the author of scholarly works, important research papers for the industry and valuable monographs and textbooks. He held the positions of associate dean and dean of the Warsaw University of Technology Faculty of Electrical Engineering. He did a lot of social work and was a honorary member of SEP and PTETiS. In 1965 Władysław Latek organized the first conference devoted to electrical machines, which since then has been continuously held every year by various Polish technical universities and is known as the International Symposium on Electrical Machines SME. Professor Latek was an outstanding academic teacher and with his assistance as a promoter 20 students obtained their doctorates. Many of his former students today are professors themselves and fill responsible positions in industry, energy production and business administration.
PL
Wydział Elektryczny Politechniki Warszawskiej powstał przez podział Wydziału Budowy Maszyn i Elektrotechniki. Po uzyskaniu samodzielności przez Wydział Elektryczny nastąpił szybki rozwój, budowa własnego gmachu i wzrost kadry. W czasie II wojny światowej, dzięki tajnemu nauczaniu, zachowano ciągłość działania. Po wojnie natychmiast uruchomiono studia - mimo strat osobowych, zniszczenia budynków i wyposażenia. Część kadry zasiliła nowo powstające politechniki, co miało duże znaczenie dla odbudowującego się i jednocześnie rozbudowującego wyższego szkolnictwa technicznego w kraju. W roku 1951 nastąpiło przyłączenie Wydziału Elektrycznego Szkoły Inżynierskiej im. Wawelberga i Rotwanda, następnie podział na dwa wydziały: Elektryczny i Łączności.
EN
Before the foundation of the independent Faculty of Electrical Engineering, lectures on electrotechnics at Warsaw Polytechnic Institute from its establishement in 1898 were given, of necessity, in Russian. In Polish the Faculty of Machine Construction and Electrotechnics operated at Warsaw University of Technology from 1915. Due to little quantity of didactic staff the division of the faculty and the isolation of independent Faculty of Electrical Engineering was possible not before 1921. The time after gaining autonomy brought rapid growth for the faculty and cadre as well as the construction of its building. During World War Two due to heroic attitude of the didactic and technical staff, the work was continued and underground teaching was provided. Just after the War even because of the loss of people and damages of buildings and the equipment, regular studies were started. Some of the cadre reinforced new universities of technology what had a tremendous impact on the technical university educational system that had been just then being rebuilt in Poland. In 1951 the Faculty of Electrical Engineering of the Wawelberg and Rotwand Engineering School was incorporated, and then the faculty was divided into two: the Electrical Engineering one and Communication one.
PL
12 stycznia 2015 roku zmarł profesor dr hab. inż. Eugeniusz Koziej, zasłużony pracownik Politechniki Warszawskiej. Profesor E. Koziej był wybitnym znawcą maszyn elektrycznych i mechatroniki. Autor podręczników, artykułów naukowych i patentów. Członek Komitetu Elektrotechniki Polskiej Akademii Nauk w latach 1993-2003. Znakomity dydaktyk i wychowawca młodzieży akademickiej, promotor i recenzent kilkudziesięciu prac dyplomowych, rozpraw doktorskich i habilitacyjnych. Prowadził wykłady w Politechnice Warszawskiej i Lubelskiej, także na Uniwersytetach Technicznych w Helsinkach i Dreźnie. Wieloletni Dyrektor Instytutu Maszyn Elektrycznych, Kierownik Zakładów: Maszyn Elektrycznych i Elektrotechniki Ogólnej. Członek Honorowy Polskiego Towarzystwa Elektrotechniki Teoretycznej i Stosowanej, aktywny działacz Stowarzyszenia Elektryków Polskich - Naczelnej Organizacji Technicznej. Założyciel Polskiego Towarzystwa Pojazdów Ekologicznych.
EN
On 12 January 2015 professor D.Sc. Ing. Eugeniusz Koziej died, meritorious worker of Warsaw University of Technology (WUT). Professor E. Koziej was an outstanding expert in electrical machines, and mechatronics. An author of university textbooks, scientific articles and patents. A member of Committee of Electrotechnics of the Polish Academy of Sciences from 1993 to 2003. A long-term worker of Faculty of Electrical Engineering at WUT, Electrotechnics Institute in Warsaw, Department of Electrical Machines of Lublin University of Technology. An excellent educator and lecturer of students; a thesis supervisor and reviewer of a few dozen of master, doctor and habilitation theses. Apart from WUT he led lectures at University of Technology in Lublin, as well as in Dresden and Helsinki. A long-term director of the Institute of Electrical Machines, head-master of Divisions of: Electrical Machines and Elecrotechnics. An honorific member of Polish Society for Theoretical and Applied Electrical Engineering, an activist of the Association of Polish Electrical Engineers at the Polish Federation of Engineering. A founder of the Polish Association of Ecologic Vehicles. Professor Eugeniusz Koziej was awarded with an Order of Polonia Restituta, Gold Cross of Merit, he got many distinctions from universities and ministries. A noble man, highly valued academic teacher, who was devoted with all his heart to science and the students.
8
Content available remote Stal elektrotechniczna. Metody wyznaczania parametrów cieplnych
PL
Przedstawiamy sposoby technicznej realizacji pomiarów współczynników przewodności i przejmowania ciepła z dokładnością wystarczającą do wykonania poprawnej analizy rozkładu temperatury wewnątrz współczesnych ustrojów elektromechanicznych.
PL
W artykule poddano analizie zagadnienia organizacyjne i dydaktyczne nauczania dyscypliny MASZYNY ELEKTRYCZNE we współczesnym, zmienionym środowisku prawnym. Idee Procesu Bolońskiego istotnie wpłynęły na plany studiów na uczelniach technicznych, szczególnie dotyczy to dydaktyki zaawansowanych przedmiotów realizowanych w cyklu wykładowym oraz poprzez uczestnictwo studentów w ćwiczeniach rachunkowych, pracach laboratoryjnych i projektowych. Konieczność głębokiego przeglądu form i treści nauczania dodatkowo została narzucona obligatoryjnym dostosowaniem całości politechnicznego kształcenia do przepisów ogólnoeuropejskich, zdefiniowanych w systemie Krajowych Ram Kwalifikacji. Niestety na konieczne zmiany metod i organizacji pracy polskich uczelni nakłada się na drastyczne obniżenie umiejętności posługiwania się narzędziami matematyki i fizyki przez kolejne roczniki maturzystów, ubiegających się o indeksy politechnik. Zgłoszony pod obrady SME 2012 referat jest pewnego rodzaju przewodnikiem dla służb odpowiedzialnych za wdrożenie nowoczesnych programów PB oraz KRK.
EN
In the article presented below issues, concerning organization and teaching of the Electrical Machines subject in a contemporary, changing legal environment were discussed. Concepts of the Bologna Process (BP) indeed influenced education plans in technical colleges, especially advanced subjects which are being taught in later years of college education and have a fundamental impact on the student's knowledge, skills and social demeanor. The need for detailed review of the structure and content of lectures, laboratory and design classes was additionally imposed with a compulsory adaptation of polytechnic education to all-European regulations, defined in the system of National Framework of Qualifications (NFQ). Unfortunately the required changes in methods and organization of Polish colleges result in a drastic reduction in the ability to employ the use of psychics and mathematics by subsequent years of graduates. This paper can be an advice to university teachers on how modern BP as well as NFQ programs should be implemented.
10
Content available remote Wirtualna technika pomiarowa w laboratoriach maszyn elektrycznych
PL
Współczesna metrologia w sposób jednoznaczny opierana jest na metodach wirtualizujących akt pomiaru. Zalety, jakimi cechują się wirtualne metody pomiarowe, sprawiają, że kwestią czasu pozostaje wykorzystywanie jeszcze metod klasycznych, opartych o mierniki wychyłowe. Stopniowo także tradycyjne przyrządy, których podzielnie zastąpiono ekranem cyfrowym, używane będą tylko do najprostszych pomiarów.
EN
In the article a modern concept, to join many metrological functions within test-stations operated by virtual systems, was described. Electrical machines are especially important objects that should be placed in a virtual environment. They are complicated devices carrying out important technological tasks. In order to perform their comprehensive examinations one should measure many different physical signals (among others: electric current, voltage, power, torque, temperature, induction, vibration parameters), then process them and (based on a proper inference – algorithm) develop a final evaluation. Described requirements complicate laboratory stations and increase the cost of apparatus. Mentioned metrological proceedings are the same for scientific, diagnostic and educational objectives. However classic measurement systems were constructed separately for different kinds of tasks. Taking as an example the virtual measurement systems of thee-phase induction motors: rotational and linear, it was shown that it is possible to build one system carrying out the needs of different clients. Configuring the measurement system is not on the hardware side but the software, which speeds up the construction of measurement systems and lowers the cost of supplying laboratories with modern, multitask equipment.
EN
Percutaneous vertebroplasty is a minimally invasive method of treating vertebral compression fractures aimed mainly at reduction of pain. It has been observed that fractured vertebral bodies filled in with cement might also influence the increase of their height and thus lead to reduction of post-traumatic spine kyphosis. The aim of the research was to assess the possibility of reducing the kyphotic deformation of operated spine through kyphosis measurement of vertebras adjacent to fracture. 24 patients underwent percutaneous vertebroplasty on account of compression fracture of 40 vertebral bodies in thoracic and lumbar regions. On digital x-ray spine images taken in patients before and after surgery the angle of kyphosis or lordosis of bodies above and below the fractured vertebra was measured with the use of the Cobb method. Vertebroplasty in the material examined caused reduction of kyphosis in 33 cases (80.48%) and correction by 5.78 degrees on average. No regularity was found either between the occurrence of correction (and its level) and operated spine region or between the possibility of kyphosis correction and time that passed between fracture and surgery.
EN
Loss of fixation between bone and implant surface is one of the main treatment problems in total hip arthroplasty. It might lead to implant instability, bone loss and treatment failure resulting in revision surgery. Surface modification is a method for improving bone response to implant and increasing implant osseointegration. However, the currently applied modifications such as hydroxyapatite coatings do not meet expectation and do not provide good clinical result. The object of the study was to evaluate the influence of acetabular cup surface modification on fixation and bone remodelling in total hip arthroplasty. Clinical and radiological outcomes were evaluated in patients two years after cementless total hip replacement. Two groups were compared: patients with acetabular component with uncoated titanium surface and patients with hydroxyapatite-coated acetabular surface. Hips X-rays were analysed for early signs of losing stability of acetabular cups. Two years after surgery the analysis of X-rays did not reveal any statistical differences in stability, migration of acetabular components of endoprosthesis between both groups. No differences were also observed in bone remodelling around implants. Particularly high percentage of cups, i.e. 17.64%, were classified into the group with high risk of early implant loosening, i.e., the group with HA coatings. Hydroxyapatite coatings on titanium cementless acetabular cups implanted by press-fit technique have no influence on their stability, bone-implant fixation and the remodelling of bone surrounding an implant two years after surgery.
PL
W ostatnich miesiącach weszły w życie nowe przepisy dotyczące postępowania z wyrobami zawierającymi azbest.
EN
The article is a summary of dozen-year experience of workers researching at Institute of Electrical Machines of Warsaw University of Technology and at Institute of Power Engineering. The professional experience has been related to technical diagnosis of engines, generators and energetic transformers. The authors form postulates to constructors and electrical machine creators. The aim of these statements is to prepare the devices suitably to be able to conduct efficient diagnostics offline as well as online. Even though the diagnostics has been taken into consideration what has succeeded in an improvement , services of motion maintenance and technical supervision have still been encountering numerous problems connected with receiving signals needed in the process of creating the right diagnosis. Crucial difficulties appear every time when the examined machine junctions are tried to be reached or appropriate sensors are installed, etc. The analysis has been done with the connection of types of signals listed below: vibration, electromagnetic, thermal.
15
Content available remote Wirtualna technika pomiarowa w dydaktyce maszyn elektrycznych
EN
In the article it is shown how to use virtual devices in theoretical teaching of subjects such as metrology and electrical machines utilization. In the preface the concept of a virtual device is defined as well as some specialized software for creating such metrological systems is described. Then characteristics of virtual devices are given all together with their construction modules (sensors, measurement cards, connectors, etc.). An important part of the article is dedicated to measurement errors, first of all the ones that appear while converting signal from analogue to digital one (in blocks a/a, a/c and c/c). The main part of the paper is dedicated to a description of a particular execution of an idea that concerns electrical machines teaching based on virtual applications. The example given shows a research station with a synchronous generator of 10 kVA rated power driven by a direct current motor. The stand is made for measuring a 3-phase generator while it is in no-load state, during a short circuit, and when it is overloaded. The generator is able to work in a co-operation with separated network as well as in a co-operation with power system (after synchronization). The station described is also prepared to calculate parameters of a 3-phase synchronous machine, Potier's reactance, for example.
16
Content available remote Cooling of electric machines by multi-phase systems
EN
A high potential for increase the power density and the efficiency of electrical machines consists in a improved cooling. A new implementation approach is in the pouring of the electric components into a medium, which guarantees a better heat emission to the case in a combined manner with a new cooling concept by utilization of change its phase, with that maximum loads can be absorbed thermally. At a realistic experimental model on the basis of a 3 kW induction motor of assembly line production the use of the different physical effects during heat storage was examined for the suitability for an electrical machine, when this equipped with chambers with technical paraffin were. There are represented the experimental investigations at a modified induction motor and with its result the potential of this development. Measurement and computations show the better cooling of the solid one and both the liquefied material compared to air circulation. On the other hand, the effect of the fusion heat is still insufficient because of bad heat conduction qualities of PCM material for the practical application. By means of thermal FEM simulations the experiments are supported and possibilities for new materials examined.
EN
Despite of applying modern biomaterials during constructing long term orthopaedic implants, in clinical practice there are still present wide range of complications, particularly concerning matter of implant - tissue interactions. Since interaction between implant and living tissue depends mainly on biomaterial surface features, we decided to modify orthopaedic alloys to improve their biological properties. The object of this experiment was in vitro evaluation of selected biological properties, particularly cytotoxicity of titanium alloy and 316L stainless steel substrates coated with SiO2 or TiO2 thin films. The coatings were synthesized by sol-gel method. Each samples was placed into mouse fibroblast culture. The cultures in presence of tested materials were maintained for three days. We found no distinct toxic effect of tested biomaterials. We noticed increase of fibroblast proliferation in cultures with uncoated titanium and particularly SiO2 coated titanium plates.
18
Content available remote 90 lat nauczania Maszyn Elektrycznych w Politechnice Warszawskiej
EN
The article is a review of teaching and scientific achievements at Warsaw University of Technology (WUT) Division of Electrical Machines (DEM). Nine years ago electrical machine experts working under professor Konstanty Żórawski’s leadership set up the Department of Electrical Machines at Warsaw University of Technology. It was the first institution in Poland whose purpose was to educate electrical machine engineers. The article shows a review of main trends connected with constructing a strong position of ELECTRICAL MACHINES discipline at WUT in the 20th century. The emphasis was on the influence in the areas of educational and research by four outstanding electrical machines teachers: Konstanty Żórawski, Henryk Kozłowski, Bolesław Dubicki and Władysław Latek. Among the issues described were the expansion of the laboratory base, development of teaching content, and changes in its organization. Elements of modern DEM teaching were shown, such as: new academic books, modern laboratory equipment, broadening the exercises for students with diagnostic elements and interesting thesis subjects. The current scientific work of the DEM scientists was described, as were the plans for the near future.
PL
W artykule zaprezentowano problemy eksploatacji i remontów jednostek napędowych tramwajów obsługujących aglomerację warszawską. Scharakteryzowano istotne cechy konstrukcyjne i eksploatacyjne obecnie wykorzystywanych silników głównych: prądu stałego (LTa-220, LTb-220, LTd-220, LTb-240) i przemiennego (STDa 200 L4, SBM 34/45-4, SBM 34/75-4). Sformułowane w wyniku analizy wskazówki kierowane są zarówno do służb utrzymania ruchu przedsiębiorstw tramwajowych, jak i konstruktorów oraz producentów silników napędowych.
EN
The article presents technical solution of modern streetcars working in the Warsaw urban agglomeration. The authors characterized important construction and operational features of these traction engines that are used nowadays. They can be direct current engines (LTa-220, LTb-220, LTd-220, LTb-240) or alternating current engines (STDa 200 14, SBM 34/45-4, SBM 34/75-4). Instructions, formulated thanks to the analysis, quoted in conclusions of the article, are directed to traffic maintenance services of streetcar operating companies and to producers of traction engines.
20
EN
The article presents, against the background of technical diagnostics development, diagnosing and monitoring methods for equipment and process engineering lines, reliable and offered at present by the Company Zaklady Remontowe Energetyki Warszawa S.A. (ZREW). These, usually very responsible and sophisticated, technical systems are driven by electric motors. Many years of experience justifies the selection of, indicated in the paper, physical quantitative, the measurement of which allows efficient elaboration of a diagnosis. First of all, an important role of the vibration signal in examination of this type of objects was singled out. The ZREW uses high class equipment and specialised diagnostic programming. The above-mentioned means make possible, after a logistic reconnaissance of objects, elaboration of proper for them, diagnostic, monitoring and supervising procedures, and of methods for measurement signals processing. The article points out the significance of organisation of computer databases and of ergonomic ways of communication with services performing measurements and with their principals. An important conclusion is the proof of how important is the firm's quality system for correct performance of diagnostic tests and for satisfactory cooperation with the company's customers. In the ZREW it is organised according to the ISO 9001:2000 norm provisions. Works, performed by the diagnostic staff of the ZREW, bring as the result, every time, lowering of operating costs of equipment with simultaneous increase of the equipment's availability and reliability. They influence directly high economic effectiveness of the company, which ordered the diagnostic tests.
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