Wyniki wyszukiwania - BazTech

1

Enhancement of power unit flexibility using pressure accumulation of hot water

Taler J., Trojan M., Taler D., Dzierwa P., Kaczmarski K., Liszka M.

Rynek Energii

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2017

|

Nr 1

78--86

EN

Calculations were performed of the thermal system of a power plant with installed water pressure tanks. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters is determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the night off-peak hours, water is heated to the nominal temperature in the feed water tank and then directed to water pressure tanks. The water accumulated during the night is used to feed the boiler in the period of peak demand for electricity. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. A financial and economic profitability analysis (of costs and benefits) is made of the use of tanks for a 200 MW power unit. Operating in the automatic system of frequency and power control (in Polish: ARCM), the tanks may also be used to ensure a sudden increase in the electric power of the unit. The results of the performed calculations and analyses indicate that installation of water pressure tanks is well justified. The investment is profitable. Water pressure tanks may not only be used to reduce the power unit power during the night off-peak hours and raise it in the periods of peak demand but also to increase the power capacity fast at any time. They may also be used to fill the boiler evaporator with hot water during the power unit start-up from the cold state.

PL

Przeprowadzono obliczenia układu cieplnego elektrowni z zainstalowanymi zasobnikami ciśnieniowymi wody. Wyznaczono maksymalne podwyższenie mocy elektrycznej bloku spowodowane zamknięciem podgrzewaczy regeneracyjnych niskoprężnych. Kocioł zasilany jest w tym czasie gorącą wodą z zasobników ciśnieniowych wody. Aby zmniejszyć moc elektryczną bloku energetycznego w czasie tzw. „doliny nocnej” podgrzewana jest woda do temperatury nominalnej w zbiorniku wody zasilającej i kierowana do zasobników ciśnieniowych wody. Zgromadzoną w okresie nocy gorącą wodę wykorzystuje się do zasilania kotła w okresie szczytowego zapotrzebowania na energię elektryczną. Wyznaczono spadki mocy elektrycznej bloku energetycznego przy różnych pojemnościach zasobników i czasach ich ładowania. Wykonano analizę finansową i opłacalności ekonomicznej (kosztów i korzyści) zastosowania zasobników dla bloku o mocy 200MW. Zasobniki mogą znaleźć zastosowanie również do nagłego podwyższenia mocy elektrycznej bloku, pracując w układzie automatycznej regulacji częstotliwości i mocy (ARCM).” Z przeprowadzonych obliczeń i analiz wynika, że zainstalowanie ciśnieniowych zasobników wody jest celowe. Inwestycja jest opłacalna. Zasobniki ciśnieniowe mogą służyć nie tylko do obniżenia mocy elektrycznej bloku w czasie tzw. „ doliny nocnej” oraz podwyższenia mocy bloku w okresie obciążenia szczytowego, ale również mogą być wykorzystane do szybkiego podwyższenia mocy w dowolnym czasie oraz mogą być zastosowane do napełniania parownika kotła gorącą wodą w czasie rozruchu bloku ze stanu zimnego.

2

Improving flexibility characteristics of 200 MW unit

Taler J., Trojan M., Taler D., Dzierwa P., Kaczmarski K.

Archives of Thermodynamics

|

2017

|

Vol. 38, no. 1

75--90

EN

Calculations were performed of the thermal system of a power plant with installed water pressure tanks. The maximum rise in the block electric power resulting from the shut-off of low-pressure regenerative heaters is determined. At that time, the boiler is fed with hot water from water pressure tanks acting as heat accumulators. Accumulation of hot water in water tanks is also proposed in the periods of the power unit small load. In order to lower the plant electric power in the off-peak night hours, water heated in low-pressure regenerative heaters and feed water tank to the nominal temperature is directed to water pressure tanks. The water accumulated during the night is used to feed the boiler during the period of peak demand for electricity. Drops in the power block electric power were determined for different capacities of the tanks and periods when they are charged. A financial and economic profitability analysis (of costs and benefits) is made of the use of tanks for a 200 MW power unit. Operating in the automatic system of frequency and power control, the tanks may also be used to ensure a sudden increase in the electric power of the unit. The results of the performed calculations and analyses indicate that installation of water pressure tanks is well justified. The investment is profitable. Water pressure tanks may not only be used to reduce the power unit power during the off-peak night hours and raise it in the periods of peak demand, but also to increase the power capacity fast at any time. They may also be used to fill the boiler evaporator with hot water during the power unit start-up from the cold state.

3

A numerical model of transient pipeline operation

Taler D., Kaczmarski K.

Czasopismo Techniczne. Mechanika

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2016

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Y. 113, iss. 1-M

231--242

EN

The aim of this study is to develop a numerical model of a steam pipeline. The energy conservation equations for the pipeline wall and steam are solved using the finite volume method (FVM). The transient temperature of the pipeline wall, steam temperature and thermal stresses can be calculated using the model developed in the paper.

PL

Celem artykułu jest opracowanie modelu numerycznego rurociągu parowego. Równania zachowania energii dla ścianki rurociągu i pary są rozwiązywane przy użyciu metody objętości skończonych (MOS). Nieustalona temperatura ścianki rurociągu, temperatura pary oraz naprężenia cieplne mogą być obliczone za pomocą modelu przedstawionego w artykule.

4

A Bi-objective Optimization Framework for Heterogeneous CPU/GPU Query Plans

Przymus P., Kaczmarski K., Stencel K.

Fundamenta Informaticae

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2014

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Vol. 135, nr 4

483--501

EN

Graphics Processing Units (GPU) have significantly more applications than just rendering images. They are also used in general-purpose computing to solve problems that can benefit from massive parallel processing. However, there are tasks that either hardly suit GPU or fit GPU only partially. The latter class is the focus of this paper. We elaborate on hybrid CPU/GPU computation and build optimization methods that seek the equilibrium between these two computation platforms. The method is based on heuristic search for bi-objective Pareto optimal execution plans in presence of multiple concurrent queries. The underlying model mimics the commodity market where devices are producers and queries are consumers. The value of resources of computing devices is controlled by supply-and-demand laws. Our model of the optimization criteria allows finding solutions of problems not yet addressed in heterogeneous query processing. Furthermore, it also offers lower time complexity and higher accuracy than other methods.

5

Real-Time Content Delivery Networks Monitoring

Kaczmarski K., Pilarski M.

Przegląd Teleinformatyczny

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2013

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T. 1, Nr 1 (19)

75-85

EN

Modern Content Delivery Networks require both monitoring and analysis tools in real-time. The first ones deliver real time alerts and system behaviour. The second are intended to offer more complicated reports which may be used for data mining, prediction or even service accounting. In this paper we present a method of covering all these functionalities by providing a real time (or almost real time) monitoring, but based on sophisticated statistics which may be basis for deeper system analysis. Our solution is based on real time MOLAP (Multidimensional Online Analytical Processing) cube creation and time series stored in a dedicated database system.

PL

Współczesne Sieci Dostarczania Treści (CDN) wymagają zarówno monitoringu, jak i narzędzi do analizy w czasie rzeczywistym. Monitoring umożliwia śledzenie zachowania systemu oraz sygnalizowanie alarmów w czasie rzeczywistym. Narzędzia do analizy umożliwiają natomiast tworzenie bardziej skomplikowanych form raportów, które mogą być wykorzystywane do eksploracji danych lub prognoz, a nawet do rozliczeń za usługi. W tym artykule prezentujemy sposób obejmujący wszystkie te funkcje, dostarczając w czasie rzeczywistym (lub prawie rzeczywistym) funkcję monitorowania, opierającą się na zaawansowanych technikach statystycznych, które mogą być podstawą do głębszej analizy systemowej. Nasze rozwiązanie oparte jest na tworzeniu kostki MOLAP (ang. Multidimensional Online Analytical Processing) w czasie rzeczywistym oraz analizie szeregów czasowych zapisanych w dedykowanej bazie danych.

6

Szalka M, Kostka J, Rokaszewski E, Kaczmarski K.

Acta Chromatographica

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2012

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Vol. 24, no. 2

163--183

EN

The new analytical method of very high pressure liquid chromatography (VHPLC) has been designed for the estimation of related substances in bisoprolol fumarate. Several columns filled with sub-2-μm totally porous and shell adsorbent have been tested and compared during the method development. The columns’ resolution was investigated. The shell adsorbent appears to have smaller resolution than the totally porous adsorbent. The tips and recommendations for the HPLC-VHPLC method transfer are presented. Significant reduction in analysis run time and solvent consumption has been obtained.

7

Unexpected aliphatic acid peak profiles — Preliminary investigations

Zapała W., Kostka J, Kaczmarski K.

Acta Chromatographica

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2011

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Vol. 23, no. 4

673--679

EN

A hypothetical retention mechanism is proposed for the modeling of the strongly distorted peak profiles of four aliphatic acids on the Acclaim RS PA2 column. The obtained experimental band profiles are mathematically described with the modified POR model of the chromatographic column.

8

Effect of mobile phase composition on the overall elution process in thin-layer chromatography

Prus W., Kaczmarski K.

Acta Chromatographica

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2011

|

Vol. 23, no. 4

681--692

EN

Phenylacetone was chromatographed on alumina with mixture of toluene and 1,4-dioxane as a mobile phase in a thin-layer chromatography (TLC) system. All the chromatograms were scanned with a densitometer. It was found that for such a binary mobile phase, there is a range of stronger component concentration that gives both peaks of Gaussian shape and triangle-like shape as well. Non-Gaussian peaks of phenylacetone chromatographed on alumina with a mixture of toluene and 1,4-dioxane were observed in the case of relatively low concentration of the latter in the mobile phase. Appropriate model describing the observed retention process is suggested.

9

Comparison of different columns in analysis of C1–C5 aliphatic acids mixture in ion exclusion chromatography and vacancy ion exclusion chromatography modes

Zapała W., Kostka J, Kaczmarski K.

Acta Chromatographica

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2011

|

Vol. 23, no. 3

377--388

EN

Ion exclusion chromatography (IEC) is a chromatographic technique based on the exclusion of dissociated sample molecules. This method has many applications in various analytical separations of weak acids. An alternative technique is the vacancy IEC (v-IEC), where the column is equilibrated with the sample solution flowing as mobile phase through the system, whereas pure water is injected as a sample. In this case, characteristic negative “vacant” peaks are obtained. The aim of this paper is to compare the efficiency of four RP-HPLC columns in the separation of C1–C5 aliphatic acids mixture by use of classical HPLC and very high pressure liquid chromatography. The investigations were conducted in IEC and v-IEC modes.

10

On Distributed Data Processing in Data Grid Architecture for a Virtual Repository

Kuliberda K., Wiślicki J., Kowalski T. M., Adamus R., Kaczmarski K., Subieta K.

Journal of Applied Computer Science

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2010

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Vol. 18, nr 2

25-55

EN

The article describes the problem of integration of distributed, heterogeneous and fragmented collections of data with application of the virtual repository and the data grid concept. The technology involves: wrappers enveloping external resources, a virtual network (based on the peer-topeer technology) responsible for integration of data into one global schema and a distributed index for speeding-up data retrieval. Authors present a method for obtaining data from heterogeneously structured external databases and then a procedure of integration the data to one, commonly available, global schema. The core of the described solution is based on the Stack-Based Query Language (SBQL) and virtual updatable SBQL views. The system transport and indexing layer is based on the P2P architecture.

11

Modelling of ion-exclusion chromatography and vacancy ion-exclusion chromatography of selected aromatic acids on strongly acidic resin in the H + form

Zapała W., Kaczmarski K

Acta Chromatographica

|

2010

|

Vol. 22, no. 1

1--25

EN

Ion-exclusion chromatography (IEC), a chromatographic technique based on exclusion of dissociated sample molecules, finds many applications in a variety of analytical separations of weak acids. Vacancy ion-exclusion chromatography (v-IEC) is an alternative technique in which the column is equilibrated with the sample solution flowing as mobile phase through the system, and pure water is injected as the sample. In this technique, characteristic negative ‘vacant’ peaks are obtained. The objective of the work described in this paper was to describe the mechanisms of retention in IEC and v-IEC for selected aromatic acids, under analytical and concentration-overload conditions, with pure water, dilute sulphuric acid solution, and dilute sulphuric acid containing a small amount of heptanol as the three mobile phases. The retention times and peak shapes predicted by use of the model were in good mutual agreement for a wide range of concentrations for all the analytes investigated.

12

Modeling of ion-exclusion chromatography and vacancy ion-exclusion chromatography of C 1 -C 6 aliphatic carboxylic acids on a weakly acidic cation-exchange resin

Zapała W., Kaczmarski K

Acta Chromatographica

|

2010

|

Vol. 22, no. 3

337--356

EN

Ion-exclusion chromatography (IEC), a chromatographic technique based on exclusion of dissociated sample molecules, finds many applications in a variety of analytical separations of weak acids. An alternative technique is vacancy ion-exclusion chromatography (v-IEC), in which the column is equilibrated with the sample solution flowing as mobile phase through the system, and pure water is injected as the sample. In this case, characteristic negative ‘vacant’ peaks are obtained. The objective of the work discussed in this paper was to investigate retention mechanisms in IEC and v-IEC for selected aliphatic acids, under analytical and concentration overload conditions, with pure water and a weakly acidic cation-exchange resin. The retention times and the peak shapes predicted by the proposed model were in a good agreement for a wide range of concentrations for all the analytes investigated in this study.

13

Dezaktywacja niklowego katalizatora uwodornienia benzenu w złożu przemysłowym

Szukiewicz M., Kaczmarski K., Stołecki K., Gołębiowski A., Borowiecki T., Sylwestrowicz R.

Przemysł Chemiczny

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2009

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T. 88, nr 12

1302-1305

14

Modelowanie przemysłowego złoża katalizatora uwodornienia benzenu

Szukiewicz M., Kaczmarski K., Stołecki K., Szarlik S.

Przemysł Chemiczny

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2008

|

T. 87, nr 4

384-387

15

Koncepcja systemu komputerowego nadzorującego aparaturę medyczną znajdującą się na sali operacyjnej

Kaczmarski K.

Aktualne Problemy Biomechaniki

|

2008

|

z. 2

83--86

PL

W ciągu kilku lat wygląd sali operacyjnej uległ diametralnym zmianom. Zauważyć można je głównie w pojawieniu się wielu urządzeń, które otaczające chirurga powodują ograniczenie i tak małej przestrzeni na sali operacyjnej. Także dostęp do tych urządzeń jest ograniczony, a praca chirurga jest uzależniona od informacji o wskazaniach urządzeń, które są przekazywane od poszczególnych członków zespołu. W celu polepszenia wydajności pracy, ergonomii i zapewnienia kontroli nad aparaturą, opracowana została koncepcja stworzenia systemu komputerowego. Dzięki systemowi personel medyczny na jednym monitorze może przeglądać wyniki badań oraz sterować urządzeniami takimi jak stół czy lampa operacyjna.

EN

The image of operating room has been changed in the last years. These changes are exposing in appearance of many medical devices. The devices surround the surgeon and diminish space of operating room. The surgeon work depends on information about variable devices, which are pass over medical staff. In order to improve the efficient, ergonomic and control features of medical devices the scheme of concept of computer system has been proposed. This system enables medical staff to watch the result of examination and control medical equipment.

16

Phenomenological modeling of separation of enantiomers by nonlinear chromatography

Szabelski P., Kaczmarski K.

Acta Chromatographica

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2008

|

Vol. 20, no. 4

513-547

EN

Separation of enantiomers by liquid chromatography is a powerful method which has long been used to obtain enantiomerically pure compounds in the pharmaceutical, food, and agrochemical industries. Optimization of such separations to achieve high-performance resolution of pairs of enantiomers is a challenging task. To this end, mathematical models of adsorption on chiral stationary phases have been widely used to predict the performance of chromatographic columns packed with these materials. In this review we discuss the basic adsorption models used in chiral separations, and their extension to specific cases. We also outline combination of adsorption models with models describing mass-transport processes in a chromatographic column. We focus on the most popular chiral stationary phases used in chromatographic separations, for which we describe recent developments in theoretical modeling of enantioselective binding.

17

Popioły lotne w inżynierii ochrony środowiska

Kaczmarski K., Witka J., Mazur K.

Ekotechnika

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2007

|

nr 2

30-33

18

Microprocessor ultrasonic sonar for the blind people

Kaczmarski K., Juda Z., Milewski G.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

|

z. 26

179-184

EN

Total or partial failure to see should not eliminate men's ability to move. One of the most important difficulties for the blind people is to pass or avoid various barriers while moving in the streets. In majority they use walking-sticks, which are limited to detect barriers laying on the ground. Other barriers like trees branches, platforms, low road signs, etc. generally are being detected to late. In order to help people who suffer that disability a system of sonar based on ultrasonic detection has been worked out. The system is applied mainly as an additional device useful for detecting barriers by space scanning on the height corresponding to men's trunk and head. Ultrasonic sensor of 40 kHz frequency and microcontroller as a basic part of the system have been applied to design and construct the device. The main function of the sonar is to calculate the time for ultrasonic wave to overcome the distance to the barrier and back as well as noise controlled signalling of barrier detection depending on it's settlement.

19

Application of mass spectrometry to the determination of total antioxidant potential

Głód B. K., Baumann M., Kaczmarski K.

Chemia Analityczna

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2006

|

Vol. 51, No. 1

51-64

EN

In this paper a new method for the delerm i nation of Total Antioxidant Potential (TAP) using mass spcclrometry has been described. The method is based on the generation of hydroxyl radicals in Fenton reaction and analysis of the product of their interaction with p-hydroxybenzoic acid - 3,4-dihydroxybenzoic acid. It has been found that the proposed assay is superior to the previously described chromatographic method with respect to analysis time. The method has been applied to the determination of TAP for some herbal extracts and melatonin.

PL

W pracy opisano nową metodę pomiaru całkowitego potencjału an ty oksydacyjnego (ĆPA) z zastosowaniem spektroskopii mas. Metoda polega na generacji rodnika hydroksylowego w reakcji Fentona, a następnie analizie produktujego reakcji z kwasem p-hydroksybenzoesowym - kwasu 3,4-d i hydroksy benzoesowego. Okazało się, że proponowana metoda jest znacznie szybsza od analogicznej metody chromatograficznej. Została ona zastosowana do oznaczania ĆPA ekstraktów ziołowych i melatoniny.

20

Use of simulated annealing for optimization of chromatographic separations

Kaczmarski K., Antos D.

Acta Chromatographica

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2006

|

No. 17

20-45

EN

The effectiveness of a hybrid of simulated annealing (SA) and the simplex algorithm for optimization of a chromatographic separation has been examined. The method has been used to solve optimization problems for separations in batch and continuous chromatographic systems under isocratic and gradient conditions. To verify the robustness of the algorithm a variety of test problems have been solved. Different objective functions have been optimized subject to different optimization constraints for several operating conditions used as decision variables. The effectiveness of the hybrid procedure has been compared with that of a random search algorithm. The hybrid method proved particularly effective for multicondition optimization involving changes of mobile-phase composition. The method is rapid and robust in location of the global optimum. It does not, moreover, require initiation of the calculations with a “feasible point”, i.e. a point for which optimization constraints are met.