Wyniki wyszukiwania - BazTech

1

Simple three-stage frequency-stabilized diode laser system using injection-locking and tapered amplifier

Szonert Jerzy, Głódź Małgorzata, Kowalski Krzysztof

Opto-Electronics Review

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2022

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Vol. 30, No. 1

art. no. e140146

EN

We developed a three-stage, amplifying, tunable diode laser system that comprises a master laser in a Littrow configuration, frequency-stabilized by dichroic atomic vapour laser lock, acousto-optic frequency shifter, injection-locked slave laser, and tapered amplifier. The slave amplifies the injected frequency-shifted master beam while suppressing (within 0.5%) the strong dependence of its intensity on the acousto-optic frequency shifter carrier frequency, thus acting as a strongly saturated optical limiting amplifier with constant output power. The resulting beam is then amplified in a tapered amplifier. The system provides an output power above 700 mW at a wavelength of 780 nm, with a time-averaged linewidth of 0.6 MHz, and a frequency drift below 2 MHz/h. Dichroic atomic vapour laser lock enables frequency stabilization in the range of 400 MHz around D2 lines of rubidium. The mode-hop-free tuning range amounts to 2 GHz. Determined by the acousto-optic frequency shifter model used, the fine-tuning range (recision of few tens kHz) spans 70 MHz. A description of the system was presented and its performance was tested. The basic components have been designed in our laboratory.

2

Computer-Assisted Modeling and Design of Compression Garments with Graded Unit Compression

Kowalski Krzysztof, Kłonowska Magdalena, Sujka Witold, Latańska Ilona, Kowalski Tomasz Marek

Autex Research Journal

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2022

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Vol. 22, no. 1

80--88

EN

This article presents a useful algorithm for designing compression products with intended and graded unit pressure along the part of the body covered with the mentioned garments. The algorithm was developed using Laplace's law and a designated experimental function describing the relationship between strength and relative elongation of knitted fabric, and the results of 3D scanning of different body parts. On this basis, two examples of products in the form of a leg sleeve and arm sleeve were designed for the treatment of lymphoedema in compression classes II and III. The presented compression product design procedure facilitates the process of designing compression garments and eliminates some errors related to this procedure.

3

Biological Properties of Knitted Fabrics Used in Post-Burn Scar Rehabilitation

Latańska Ilona, Kowalski Krzysztof, Kłonowska Magdalena, Jaworska Aleksandra, Doś Janusz, Karbowski Krzysztof, Sujka Witold

Autex Research Journal

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2022

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Vol. 22, no. 3

343--349

EN

Compression therapy along with the use of compression materials is one of the main prevention methods against scars and keloids. Compression knitted fabrics must be characterized by parameters that enabling to reaching class I compression (16–24 mmHg). When constant pressure higher than capillary vessels pressure is applied to scars, it will have a negative influence on formation of keloids and significantly prevents their hypertrophy. Long-term pressure causes tissue hypoxia, slowed-down metabolism, and reduction of the amount of fibroblasts. One of key elements of compression therapy is choosing the required knitted fabric with necessary structure and physicomechanical parameters as well as designing methodology based on Laplace law, which will ensure the application of desired value of single-unit pressure on post-burn scar. Apart from physicomechanical parameters, a medical device, such as compression garment, must be characterized by high level of biocompatibility. An added value in terms of functional parameters is the antibacterial action of the product. It was obtained from the fibers used which contain a compound in their matrix and out of which silver ions are released. Additionally, the antibacterial action was also obtained via impregnation of the knitted fabric in RUCO-BAC AGP which contains silver. In the course of the research presented in the article, compression fabric was designed with a special construction - a knitted fabric comprising two layers. The first layer, which is in direct contact with human skin, is manufactured out of a yarn with conductive-diffusive characteristics. The second layer is made of microfibers which keep the moisture out of skin surface and also diffuse it to the outside. The following article describes the final stage of developing a compression garment aiding the external treatment process; the mentioned stage is related to biological tests such as microbiological contamination, cytotoxicity, sensitization, and irritation. The article closes a series of publications presented by the Authors in bibliography. It also presents the antibacterial activity tests done on the developed double-layer knitted fabric enriched with silver. The obtained results suggest that the fabric may be used not only in compression therapy, but also in the field of cosmetics and aesthetics.

4

Algorytm wyznaczania przemieszczeń radialnych szyn toru suwnic kołowych

Bryś Henryk, Ćmielewski Kazimierz, Kowalski Krzysztof

Przegląd Geodezyjny

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2021

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R. 93, nr 1

9--11

PL

Bezpieczeństwo użytkowania suwnic oraz ich bezawaryjność uzależnione są od spełnienia wymagań geometrycznych jej wszystkich podzespołów oraz torów podsuwnicowych, które podlegają okresowym pomiarom weryfikacyjnym, podczas których sprawdzane są warunki geometryczne odpowiednimi metodami geodezyjnymi, zgodnie z obowiązującymi normami oraz instrukcjami branżowymi. W pracy przedstawiono opracowany przez autorów algorytm wyznaczania współrzędnych poziomych punktów kontrolowanych zdeformowanego toru kołowego suwnicy obrotowej. W wyniku wyrównania Metodą Najmniejszych Kwadratów otrzymywane są najbardziej prawdopodobne wartości przemieszczeń radialnych w odniesieniu do wyrównanego koła toru, w postaci poprawek rektyfikacyjnych.

EN

The safety of using cranes and their failure-free operation depend on meeting the geometrical requirements of all its components and crane tracks. Crane tracks are subject to periodic verification measurements, during which geometric conditions are checked by appropriate geodetic methods, in accordance with the applicable standards and industry instructions. The paper presents an algorithm developed by the authors for determining the horizontal coordinates of the controlled points of a deformed circular track of a rotary crane. As a result of the Least Squares Method, the most probable values of radial displacements in relation to the aligned wheel of the track are obtained in the form of rectification corrections.

5

Threats to Wastewater Treatment Plant in Combined Sewer System – Analysis of Problems and Possible Solutions on the Example of Lodz

Sakson Grażyna, Brzezińska Agnieszka, Kowalski Krzysztof

Rocznik Ochrona Środowiska

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2020

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Tom 22, cz. 2

1132--1144

EN

Municipal WWTP are exposed to the inflow of toxic substances, which may impede their proper functioning, especially of the biological part. In the case of combined or hybrid sewer systems, additionally, in wet weather, there may appear a rapid inflow of a mixture of domestic and industrial sewage, and stormwater in an amount exceeding the capacity of the devices, causing the need to discharge parts of not fully treated wastewater through the bypass channel. In such situations, the receivers are exposed to an inflow of increased amounts of pollutants. The article presents the concept of a monitoring, early warning and sustainable management system for the Lodz wastewater treatment plant, which will allow minimizing pollutant emissions to the aquatic environment.

PL

Miejskie oczyszczalnie ścieków są narażone na napływ substancji toksycznych, które mogą utrudniać ich prawidłowe funkcjonowanie, zwłaszcza części biologicznej. W przypadku ogólnospławnych lub mieszanych systemów kanalizacyjnych dodatkowo w czasie pogody mokrej może pojawić się gwałtowny dopływ mieszaniny ścieków bytowo-gospodarczych i przemysłowych oraz wód opadowych w ilości przekraczającej przepustowość urządzeń, powodując konieczność zrzutu części nie w pełni oczyszczonych ścieków przez kanał ominięcia. W takich sytuacjach odbiorniki są narażone na napływ zwiększonych ilości zanieczyszczeń. W artykule przedstawiono koncepcję systemu monitorowania, wczesnego ostrzegania i zrównoważonego zarządzania łódzką oczyszczalnią ścieków, który pozwoli zminimalizować emisję zanieczyszczeń do środowiska wodnego.

6

Badanie eksperymentalne modelu zestawu zdalnego zintegrowanego pomiaru temperatury w realnej atmosferze pomieszczenia zamkniętego

Bryś Henryk, Ćmielewski Kazimierz, Kowalski Krzysztof

Przegląd Geodezyjny

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2020

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R. 92, nr 10

12--14

PL

W pracy przedstawiono wyniki testowania modelu zestawu zdalnego, zintegrowanego pomiaru temperatury wzdłuż osi celowej instrumentów geodezyjnych w realnej atmosferze pomieszczenia laboratorium geodezyjnego.

EN

This work presents the results of researches of the remote model of integrated temperature measurement set along line-of-sight of surveying instruments in real indoor atmosphere.

7

Selecting Appropriate Longitudinal Rigidity of Knitted Fabric in Compression Products of Standardised Size

Kowalski Krzysztof, Kłonowska Magdalena, Ilska Anita

Fibres & Textiles in Eastern Europe

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2020

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Vol. 28, no. 3 (141)

44--49

EN

Based on the models developed, the changes in unit pressure exerted by ready-made compression products were evaluated in dependence on the longitudinal rigidity, compression class, dimensional tolerance and product size. Tests made it possible to determine the maximum permissible values of longitudinal rigidity for individual compression classes and product sizes, which, if not exceeded, ensure that the pressure exerted falls within the given compression class. Experimental verification carried out on an example of a commercial compression product from the first and second compression classes showed that the main reason for the differences between the declared and experimentally determined values of unit pressure was the overestimated longitudinal rigidity of the knitted fabric and dimensional tolerance of the size ranges and errors in the design procedure, resulting from not sticking to the principle of designing the product for the middle circumference value and the middle pressure from the compression class.

PL

Na podstawie opracowanych modeli dokonano oceny zmian nacisku jednostkowego gotowych wyrobów uciskowych w zależności od sztywności rozciągania, klasy ucisku oraz tolerancji wymiarowej i wielkości rozmiaru. Badania umożliwiły wyznaczenie maksymalnych, dopuszczalnych wartości sztywności rozciągania dzianiny dla poszczególnych klas ucisku i rozmiarów wyrobu, których nie przekroczenie gwarantuje naciski w granicach danej klasy ucisku. Eksperymentalne badania weryfikacyjne, przeprowadzone na przykładzie komercyjnych wyrobów uciskowych dla I i II klasy ucisku wykazały, że główną przyczyną różnic między deklarowanymi wartościami nacisku jednostkowego a wyznaczonymi eksperymentalnie są zawyżone wartości sztywności rozciągania dzianiny i wielkości tolerancji wymiarowej przedziałów oraz błędy w procedurze projektowania związane z nieprzestrzeganiem zasady projektowania wyrobu na środkową wartość obwodu z przedziału rozmiaru i środkową wartość nacisku danej klasy ucisku.

8

Evaluation of energy saving possibilities in cyclic fixed-bedadsorption process

Kowalski Krzysztof, Gabruś Elżbieta, Downarowicz Dorota

Chemical and Process Engineering

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2020

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Vol. 41, nr 3

209–-219

EN

The cyclic Electrothermal Temperature Swing Adsorption (ETSA) process in a fixed-bed column withSupersorbon K40 activated carbon (AC) was applied to remove propan-2-ol (IPA) from air. The bedwas electrothermally regenerated using direct resistive heating method. The tests were performed inthe range of operating parameters: IPA loading 0.18-0.26 kg/kg, voltage 19.5 V, set-point temperature393–403 K, nitrogen flow rate 0.12 m3/h.The analysis revealed, that raising the bed temperature resulted in an increase of desorption degree ofadsorbate, reduction of regeneration time and an increase in the energy consumption. The applicationof insulation enabled reduction of energy consumption and regeneration time by 27% and 10%,respectively.

9

Czułość detekcji zmian struktury w stali NDT SHM w transporcie

Żurek Zbigniew Hilary, Stokłosa Zbigniew, Chmiela Bartosz, Idziak Paweł, Kowalski Krzysztof

Napędy i Sterowanie

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2019

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R. 21, nr 1

66--73

PL

Metody defektoskopowe dedykowane szczególnie do diagnozowania deformacji i degradacji elementów stalowych wymagają szczegółowych badań parametrów magnetycznych i elektrycznych. W opracowaniu zamieszczono wybrane wyniki badań dotyczących możliwości wykrywania zmian strukturalnych za pomocą metod indukcyjnych. Z grupy metod indukcyjnych opisano badania polegające na rozdziale i szczególnej interpretacji przebiegu składowych impedancji w funkcji pulsacji pola magnetycznego w układzie współrzędnych kartezjańskich, unormowanych według zależności F. Förstera. W wybranych zakresach częstotliwości możliwa jest diagnostyka zarówno stanu powierzchni, jak i głębszych warstw materiału. Zainteresowanie badaniami nieniszczącymi, analizą rozwoju defektu oraz skutecznym i wczesnym wykrywaniem nastąpiło po katastrofie kolejowej w Eschede.

EN

Flaw detection are especially dedicated to diagnosing structures of their deformation and degradation require detailed tests of parameters magnetic and electric. The study includes selected results research related to the possibility of detecting structural changes with the help of induction methods. Inductive methods have been described in research involving chapter and special interpretation of the course of impedance components in function magnetic field pulsation in the Cartesian coordinate system according to F. Förster. In selected frequency ranges, it is possible to identify surfaces and deeper layers of material up to 8 mm. The sensitivity of defect detection using these dependencies is discussed. Effective detection of defects in transport took place several years after (Eschede).

10

Magneto - sprężystość w stalach krzemowych diagnostyka struktury i defektu - eksperyment

Żurek Zbigniew Hilary, Chmiela Bartosz, Idziak Paweł, Kowalski Krzysztof, Wolnik Piotr

Maszyny Elektryczne : zeszyty problemowe

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2019

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Nr 1 (121)

97--104

PL

Blachy krzemowe o zastosowaniach elektrotechnicznych są produkowane ze względu na przeznaczenie. W obwodach magnetycznych transformatorów struktura blach jest projektowana ze względu na zgodność kierunku magnesowania z kierunkiem wektora indukcji. Są to blachy o strukturze zorientowanej (GO - e.g. anisotropic transformer sheets). W napędach przetwarzających energię pola magnetycznego na ruch obrotowy stosujemy blachy o strukturze niezorientowanej (NGO - e.g. isotropic or generator sheets). Defekty struktury będące wynikiem cięcia lub wycinania (dowolnymi technikami mają wpływ na deformację kierunku magnesowania bez względu na stosowane techniki cięcia. W procesie tym uczestniczą zjawiska magnetosprężyste i odwrotne, znane jako efekty Vilariego i Joule’a. W artykule opisano kierunkowe zmiany magnesowania na dwóch modelach testowych przygotowanych z blachy krzemowej M130 w obszarze materiałowym, elektrotechnicznym i mechanicznym, a także w obszarze badań nieniszczących NDT (Non-destructive testing) i SHM (Structural health monitoring) monitorowanie stanu strukturalnego SHM, a także monitorowanie stanu w procesie eksploatacji (ang. Condition Monitoring - CM).

EN

Silicone sheets for electrical purposes are made for their intended purpose. In transformer magnetic circuits, the sheet structure is designed due to the compatibility of the direction of magnetization with the direction of the induction vector. These are oriented metal sheets (for example, anisotropic transformer sheets). In drives that convert the energy of a magnetic field into rotational motion, we use plates with a non-oriented structure (NGOs — for example, isotropic or generator sheets). Design defects resulting from cutting or cutting (using any methods that affect the deformation of the magnetization direction, regardless of the cutting methods used.) This process includes magneto-elastic and backward effects, known as the Vilary and Joule effects. tests prepared from silicon steel sheet M130 in the material, electrical and mechanical fields, as well as NDT (non-destructive testing) and SHM (Structural health monitoring), monitoring the state of structures SHM, and monitoring the state (Condition Monitoring - CM).

11

Monitoring, early warning and sustainable management system for Lodz wastewater treatment plant as a water protection tool

Sakson Grażyna, Brzezińska Agnieszka, Kowalski Krzysztof

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2019

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z. 66, nr 3

5--16

EN

Municipal wastewater treatment plants are exposed to the inflow of toxic substances, which may hamper or even preclude their proper functioning, especially of the biological part. In the case of combined or hybrid sewer systems, additionally, in wet weather, there may appear a rapid inflow of a mixture of domestic and industrial sewage, and stormwater in an amount exceeding the capacity of the devices, causing the need to discharge parts of not fully treated wastewater through the bypass channel, which may reduce overall treatment effects. In such situations, the receivers are exposed to an inflow of increased amounts of pollutants, which on the one hand causes a threat to the aquatic environment, on the other, may result in administrative fines for the treatment plant resulting from non-compliance with the conditions of the water permit, as well as costs of removing the effects of failure. The article presents the concept of a monitoring, early warning and sustainable management system for the Lodz wastewater treatment plant, which will allow minimizing pollutant emissions to the aquatic environment. The system will be based on data from the municipal pluviometer network, measurement of flows in combines sewer overflows and newly built sewage quality monitoring stations equipped with on-line probes. The resulting data will allow to predict quantity and quality of inflow to the treatment plant, which will allow for an early warning about the dangers. In consequence decision-making to improve the safety of its operation will be possible.

12

Heat transfer in helical coil heat exchanger:An experimental parametric study

Kowalski Krzysztof, Downarowicz Dorota

Chemical and Process Engineering

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2019

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Vol. 40, nr 1

101–-114

EN

Helical coil heat exchangers are widely used in a variety of industry applications such as refrigerationsystems, process plants and heat recovery. In this study, the effect of Reynolds number and theoperating temperature on heat transfer coefficients and pressure drop for laminar flow conditions wasinvestigated. Experiments were carried out in a shell and tube heat exchanger with a copper coiledpipe (4 mm ID, length of 1.7 m and coil pitch of 7.5 mm) in the temperature range from 243 to 273 K.Air – propan-2-ol vapor mixture and coolant (methylsilicone oil) flowed inside and around the coil,respectively. The fluid flow in the shell-side was kept constant, while in the coil it was varied from 6.6to 26.6 m/s (the Reynolds number below the critical value of 7600). Results showed that the helicalpipe provided higher heat transfer performance than a straight pipe with the same dimensions. Theconvective coefficients were determined using the Wilson method. The values for the coiled pipe werein the range of 3–40 W/m2·K. They increased with increasing the gas flow rate and decreasing thecoolant temperature.

13

Application of a Thermal Mannequin to the Assessment of the Heat Insulating Power of Protective Garments for Premature Babies

Krucińska Izabella, Skrzetuska Ewa, Kowalski Krzysztof

Autex Research Journal

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2019

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Vol. 19, no. 2

134--146

EN

In this study, the new tool for measuring thermal insulating power of garments for premature babies under coupled heat and moisture transport was developed. The thermal mannequin corresponds to the body weight and size of a premature baby born in the thirty fourth week of pregnancy. The mannequin surface temperature can be set at various levels, while the heat loss is measured in W/m2. The mannequin is divided into eleven independent heating zones and seven independent zones of moisture evolution. The study also presents the test results of heat insulating power obtained for the newly developed garment set with commercially available garment set for babies, conducted under different climatic conditions. The results exhibit the advantage of the new material construction of the garment over the commercially available one.

14

Modelling of influence of mechanical stresses arising in magnetic circuit on magnetizing characteristic

Idziak Paweł, Kowalski Krzysztof

Archives of Electrical Engineering

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2019

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Vol. 68, nr 1

209--220

EN

An algorithm of determination of mechanical stresses and deformations of the magnetic circuit shape, caused by forces of magnetic origin, is presented in this paper. The mechanical stresses cause changes of magnetizing characteristics of the magnetic circuit. The mutual coupling of magnetic and mechanical fields was taken into account in the algorithm worked out. A computational experiment showed that it was possible to include the interaction of both fields into one numerical model. The elaborated algorithm, taking into account the impact of mechanical stresses on magnetic parameters of construction materials, can be used in both the 2D and the 3D type field-model.