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1
Content available Condition for application of logistic principles in practice of urban public passenger transport in the city of Omsk
Mochalin S., Kasper M., Nikiforov O., Levkin G.
Transport Problems
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2017
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T. 12, z. spec.
71--86
EN
The task of increasing efficiency and quality of public transport has gotten special acuteness for large cities of Russia in connection with expansion of service by commercial carriers. There have no works done on the city of Omsk, where the transport system has its own characteristics. In this paper, characteristics of Omsk urban public transport are researched. The scheme that clearly demonstrates what factors have a negative impact on the development and functioning of the Omsk passenger transport system is developed. The measures that improve the efficiency of the passenger transportation system and provide an opportunity to advance the implementation of logistics principles are proposed. The activities took into account the experience of reforming the public transport system in other cities, the characteristics of the Omsk city system and a view to engagement of other scientists in this field of science.
2
Content available Emission of metal-oxide particles from IC-engines
Ulrich A, Mayer A., Kasper M., Wichser A., Czerwiński J.
Silniki Spalinowe
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2011
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R. 50, nr 1
72-88
EN
All conventional piston-driven combustion engines emit metal oxide particles. The main sources are the abrasion between piston-ring and cylinder, abrasion in the bearings, catalyst coating, lube-oil additives, and fuel additives for promoting the exhaust-gas after-treatment. Metal oxides, especially from transition metals, are very toxic when they are very fine. These particles have a high BET surface and penetrate the biological system. Hence, these particles must be scrutinized for quantity, size distribution and composition. This paper draws from published data and mainly the VERT certification tests, which prescribe a size specific metal analysis. The total mass of metal oxide is 0.1 - 1 mg/km, which appears negligible. But these particles are in the 10 - 20 nm size range. Hence, this small mass represents 1015 particles per kilometer. This is approximately the same number as soot particles emitted by diesel engines. Public health should focus on the metal oxide particles that are smaller and probably more toxic than the soot particles. SI engines run at higher RPM and therefore emit more metal oxide particles than Diesel engines. Highly efficient filtration of such particles seems therefore necessary for all engine categories.
PL
Wszystkie konwencjonalne tłokowe silniki spalinowe emitują cząstki tlenków metali. Głównymi źródłami tej emisji są: zużycie ścierne pomiędzy układem tłok-pierścień i cylinder, zużycie ścierne zachodzące w łożyskach, powłoka reaktora katalitycznego, dodatki oleju smarującego, dodatki do paliwa wspomagające pozasilnikową neutralizację toksyczności spalin. Tlenki metali, zwłaszcza metali przejściowych, są bardzo toksyczne, gdy mają niewielkie wymiary. Te cząstki metali mają dużą powierzchnię BET i przenikają do systemu biologicznego. Dlatego muszą być szczegółowo zbadane pod kątem ich ilości, rozkładu wymiarowego i składu chemicznego. Niniejszy artykuł zawiera dane i głównie testy certyfikacyjne VERT, opisujące analizę wymiarową wybranego metalu. Masa całkowita tlenku metalu wynosi od 0,1 do 1 mg/km, co wydaje się wartością nieistotną. Należy jednak zaznaczyć, iż wymiar powyższych cząstek mieści się w zakresie 10- 20 nm. Skutkiem tego, tak niewielka masa oznacza 1015 cząstek na 1 km, co jest w przybliżeniu taką samą wartością, jak ilość cząstek sadzy emitowanych przez silniki o zapłonie samoczynnym. Troska o zdrowie społeczne powinna uwzględniać emisję cząstek tlenków metali, których wymiary są mniejsze i prawdopodobnie bardziej toksyczne niż cząstki sadzy. Silniki o zapłonie iskrowym osiągają większe prędkości obrotowe, dlatego emitują więcej cząstek tlenków metali niż silniki o zapłonie samoczynnym. Wysokosprawne odfiltrowanie rozważanych cząstek wydaje się konieczne przy zastosowaniu w silnikach wszystkich kategorii.
3
Content available Propozycja wysokoskalowalnej metody replikacji danych Theta dla rozproszonych systemów transakcyjnych
Kasper M., Dobrowolski G.
Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
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2011
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T. 15, z. 2
209-217
PL
W artykule przedstawiona została propozycja nowej metody replikacji danych w systemach z dużą ilością węzłów, zaprojektowaną dla systemów, w których wymagany jest bardzo duży poziom skalowalności. Metoda przystosowana jest do pracy w systemach heterogenicznych pracujących na różnorodnych platformach sprzętowych, z różnymi systemami operacyjnymi i bazami danych. Artykuł zawiera prezentację metody, opis komunikacji i komponentów systemy oraz prezentację sposobu zarządzania transakcjami.
EN
The aim of this paper is a proposition of the new replication method for distributed systems with large number of nodes, which is suitable for systems in which demand on high level of scalability is a key issue. The approach is designed for systems working in heterogeneous environments with various platforms, operating systems or database vendors. The article contains presentation of Theta method, description of the communication layer and system components, and presentation of transaction management for the proposed method.
4
Content available Vert particle filter test procedure and quality standard for new and in-use diesel engines
Mayer A., Czerwinski J., Kasper M., Leutert G., Heeb N. V., Ulrich A., Jaussi F.
Journal of KONES
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2010
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Vol. 17, No. 4
313-322
EN
A new approach is needed to test particle filters for retrofitting Diesel engines. Considering the toxicity of the particles as also the physical and chemical attributes of particle filters, the optimal scheme is to test the components themselves independent of the deployment. That scheme ensures the highest effectiveness with least effort. It also enables evaluation of worst-case situations and assesses the hazards of secondary emissions. The Swiss standard SNR 277 205, which mandates the VERT test procedure, is a first step in that direction. The solution is derived from the physics of the filter media. The filtration of fine particles essentially depends on the particle size and the space velocity. The attributes of the emitting engine are only insignificantly relevant. Hence the physics and chemistry of particle filters can be investigated independent of the engine and its deployment duty. This concept facilitates a very thorough investigation of the size-dependent filtration, aging susceptibility, secondary emissions and extreme situations. Filter systems, which pass this detailed test, perform equally well in every retrofit configuration. This filter test concept was implemented 1998 in the VERT project and is successful for assessing retrofltting [4]. VERT approved fllter systems are already deployed in the Low Emission Zones of Europe, North and South America.
5
Content available Improvement of air quality in vehicle cabins by nanoparticle filtration
Burtscher H., Mayer A., Loretz S., Keller A., Kasper M., Czerwinski J.
Journal of KONES
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2010
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Vol. 17, No. 4
79-88
EN
A filter system is presented which allows the reduction of the concentration of ultrafine particles in vehicle cabins to very low levels. The original ventilation system is switched to the recirculation mode and all cabin intake air is supplied via a retrofitted filter system. Tests with a variety of different vehicles (from passenger cars to coaches) show the efficiency of the system. Filters incorporated in present ventilation systems remove large particles, for example pollen, but usually are inefficient for removing very small particles. This is demonstrated by Fig. l, where the particle number concentration outside and inside a car is plotted during a journey near Zurich. It is obvious that the concentrations inside and outside are more or less identical. All windows were closed during this measurement. Tests with a number ofdifferent all cars showed similar results. The filters included in today 's ventilation systems usually cannot remove nanoparticles, and so vehicle cabin indoor and outdoor nanoparticle concentrations are more or less identical. The nanocleaner, consisting of a very effident filter and a high performance blower, allows reduction of the particle concentration in the cabin from several hundreds of thousands or millions per cc. to a few thousand per cc., equivalent to remote woodland, the total exposed dose being reduced by some two orders of magnitude.
6
Content available Particle filter test procedure and quality standard for diesel engines
Mayer A., Czerwinski J., Kasper M., Leutert G., Heeb N., Ulrich A., Jaussi A.
Journal of KONES
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2009
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Vol. 16, No. 2
305-314
EN
A new approach is needed to test particle filters for retrofitting Diesel engines. Considering the toxicity of the particles as also the physical and chemical attributes of particle filters, the optimal scheme is to test the components themselves independent of the deployment. That scheme ensures the highest effectiveness with least effort. It also enables evaluation of worst-case situations and assesses the hazards of secondary emissions. The Swiss standard SNR 277 205, which mandates the VERT test procedure, is a first step in that direction. Occupational health specialists have studied the toxicity of ultraflne particles for more than 100 years. Extremely toxic are the particles intruding into the lung. Larger particles, which are always naturally present, are intercepted in the upper respiratory paths. The body then expels these larger particles rapidly via the mucus and cilia. The new manmade particles less-than l mi m, however massively intrude into the fine pulmonary alveoli, which do not have the cleansing mechanism. The targeted efficiencies for evaluating modern filters are evident from the progress achieved. Many filters have filtration rates exceeding 99.9%, albeit the directives [4] only require 97%.
7
Content available Air quality filtration in vehicle cabins
Burtscher H., Mayer A., Loretz S., Keller A., Kasper M., Czerwinski J.
Journal of KONES
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2009
|
Vol. 16, No. 2
59-69
EN
A filter system is presented which allows the reduction of the concentration of ultrafine particles in vehicle cabins to very low levels. The original ventilation system is switched to the recirculation mode and all cabin intake air is supplied via a retro fitted filter system. Tests with a variety of different vehicles (from passenger cars to coaches) show the efficiency of the system. Number concentration of particles inside and outside a car, the nanoparticle filtration system, fllter-efficiency: transmission for the new filter and for the filter loaded to apressure drop of 2.9 mbar, setup of the filter with integrated prefilter for course particles and blower, prototype of the filter system, main filter, prefilter and blower are included the system operated by an external control box, containing the drive electronics for the blower and displays for filter pressure drop and time meter, filter pressure drop as function of operating time in a highly polluted road tunnel, a possible solution to mount the filter system, particle concentration inside and outside the car (passenger car), concentration drops to very low levels, particle concentration inside and outside a passenger car with the filter turned on, two nanocleaner filter systems mounted in a school bus, filter system for buses installed in the luggage compartment are presented in the paper.
8
Niemiecka ustawa OZE – Erneuerbare-Energien-Gesetz (EEG)
Kasper M.
Czysta Energia
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2008
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Nr 12
21-21
9
Content available Zastosowanie blokad, poziomów izolacji oraz protokołów zarządzania konkurencyjnością do zwiększania wydajności i skalowalności systemów baz danych
Kasper M.
Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
|
2008
|
T. 12, z. 1
55-65
PL
Wzrost ilości danych gromadzonych, przechowywanych i przetwarzanych we współczesnych systemach informatycznych wymusił konieczność stosowania coraz bardziej rozbudowanych i złożonych systemów, czego oczywistą konsekwencją jest trudniejsza budowa i zarządzanie takimi systemami. W niniejszym artykule przedstawione zostały trudności występujące podczas realizacji złożonych systemów przetwarzania danych współpracujących ze zcentralizowanymi lub rozproszonymi bazami danych. Znajomość zagadnień opisywanych w artykule pozwala uniknąć niepotrzebnych problemów podczas tworzenia i użytkowania systemów informatycznych współpracujących z bazami danych, gdyż duża część tych utrudnień jest wynikiem fizycznych ograniczeń zrealizowanych systemów baz danych.
EN
Nowadays, increase in number of data gathered, stored and processed in database systems forced us to use complex, complicated systems, which of course causes implementation and maintenance of such systems more difficult. This article presents difficulties that can appear during realization of any complex data processing system which cooperates with centralized or distributed database system. Familiarity with presented issues allow one to avoid unnecessary troubles in creating and maintaining systems working with databases, since many of this inconveniences are caused by database's physical limitations.
10
Content available Replikacja w systemach baz danych zaprojektowanych w architekturze wielowarstwowej
Kasper M.
Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
|
2008
|
T. 12, z. 2
349-358
PL
W ostatnich latach zaproponowano wiele różnych metod replikacji danych w systemach baz danych. Rozwiązania te charakteryzują się zwiększeniem skalowalności systemów, uodpornieniem na awarie poszczególnych elementów, czy nawet całych lokalizacji, i co za tym idzie - zwiększeniem wydajności i dostępności systemów. W przypadku systemów transakcyjnych większość z najbardziej popularnych w ostatnim czasie metod replikacji opiera się na architekturze wielowarstwowej, wykorzystując dodatkową warstwę pośrednią (middleware), do której przeniesione zostały z motoru bazy danych czynności związane z kolejkowaniem i współbieżnym wykonywaniem konkurencyjnych transakcji. W artykule przedstawione zostały zagadnienia związane z realizacją systemów replikacji przy wykorzystaniu warstwy middleware.
EN
Researches in database replication field, which have been made in recent years, allowed to design and implement many approaches for database replication. The most important features of proposed solutions are improved scalability and system's fault tolerance, and as a result of both of them increased overall performance and availability of the replication systems. Majority of recent approaches for transactional data replication are based on multilayer architectures with middleware tier between client and database tier. In this article there is a presentation of solutions used for realization of middleware-based database replication.
11
Content available remote Influences of Alternative Fuels GTL, RME and ROR on Combustion and Emissions of a Modern HD-Diesel Engine
Czerwinski J., Zimmerli Y., Neubert T., Heitzer A., Kasper M.
Silniki Spalinowe
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2007
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R. 46, nr SC3
180-200
EN
Due to the limited energy resources as well as due to increasing CD2-emissions the importance of alterative- and biogene fuels is continuously increasing. Investigations of the engine operation were performed on a latest technology Liebherr engine for construction machines. It was operated using crude rapseed oil (RDR)'), rapeseed oil methyl ester (RME), synthetic Gas-To-Liquid fuel (GTL) and diesel (as reference fuel). The combustion diagnostics, the performance of the injection system as well as the pollutant emissions, including unlimited nanoparticles were assessed. The most important findings ean be summarized as joilows : Fuel injection - Both, RME and RDR shortened the injection delay which was due to a quicker increase of injection pressure and a faster needle lift, - the highest maximum injection pressure was observed with RDR (1610 bar), followed by RME (1580 bar), Diesel (1450 bar) and GTL (1410 bar), - As compared to diesel, GTL exhibited no significant differences of hydraulic behavior. Combustion - Usually, GTL caused a shorter ignition delay, but it burned slower, so that 50% of heat release took place at the same CA-position, as for Diesel. in addition, GTL provoked a lower rate of pressure raise and reduced the maximum combustion pressure. These effects were particularly pronounces at lower and medium loads. - At higher engine load RDR and RME started to bum earlier and at a higher rate, than Diesel and GTL. Therefore, 50% of the heat release followed with ROR and RME 1-2 CA earlier which had consequences for the NOx emissions. Limited emissions and energy consumption GTL lowered generally ail emission components - as compared to standard Diesel fuel. In addition, the energy consumption with GTL was equal or slightly lower. RME lowered CO and HC emissions and increased NOx emissions at ail operating points. It lowered PM at higher engine loads and increased PM at lower engine loads. RME had no effect on specific energy consumption. ROR lowered CO, HC and PM at ail operating points by at least 50% or more. In the high-load-operation RDR reduced the specific energy consumption (approx. 2%) and increased NOx (up to approx.5%). At low-load-operating points (1500 rpm/10%) ROR did not affect CO and NOx, but increased PM emissions and energy consumption. Nanoparticle emissions - GTL and diesel nanoparticle emissions were identical, - Both RME and RDR moved the PSD spectra to smaller sizes and increased the nuclei mode due to spontaneous condensate formation, - Both RME and RDR caused lower particle emissions at high load and higher emissions at low load, The use of ROR resulted in a particularly high portion of condensates (SDF) at low load and idling.
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