Filters
total: 38
filtered: 29
Search results for: TW LEGGETTA-WILLIAMSA
-
Positive solutions to second order four-point impulsive problems with deviating arguments
PublicationStosując tw. Leggetta-Williamsa, podano warunki dostateczne na istnienie dodatnich rozwiązań dla czteropunktowych problemów brzegowych dla równań różniczkowych rzędu drugiego z odchylonymi argumentami. Dyskutowane były problemy gdy argument odchylony był typu opóźnionego lub wyprzedzonego.
-
Three positive solutions to second-order three-point impulsive differential equations with deviating arguments
PublicationStosując tw. Leggetta-Williamsa, pokazano że rozpatrywany trzypunktowy problem brzegowy z impulsami ma dodatnie rozwiązania (trzy). Otrzymane twierdzenia dotyczą przypadku opóźnionego oraz wyprzedzonego. W pracy podano przykład i pokazano, że przyjęte założenia są spełnione.
-
Positive solutions to second order four-point boundary value problems for impulsive differential equations
PublicationPraca dotyczy problemów brzegowych dla równań różniczkowych drugiego rzędu z impulsami. Podane zostały warunki dostateczne na istnienie trzech dodatnich rozwiązań takich problemów z czteropunktowymi warunkami brzegowymi. W badaniach korzystano z twierdzenia Leggetta-Williamsa.
-
Removal and speciation of heavy metals in the constructed wetland treating landfill leachate
PublicationThe results of heavy metals removal and speciation of metals at two treatment wetlands receiving landfill are discussed. The first TW is a surface flow facility consisting of 10 ponds. The next TW is a newly constructed pilot-scale facility consisting of three beds with alternately vertical and horizontal sub-surface flow. The metals concentrations were analysed in leachate(both TWs) and bottom sediments (surface flow TW). Seasonal...
-
Zarządzanie terminowością w projektach. Wskaźniki i narzędzia
PublicationCzas jest istotnym elementem tzw. trójkąta projektu, dlatego też terminowość, rozu-miana, jako realizacja przedsięwzięcia w zadanym czasie, to parametr, który powinien podle-gać szczególnemu nadzorowi, a ryzyko nieterminowej realizacji powinno być wykrywane niezwłocznie. Istniejące już metody, takie jak np. wartość wypracowana (j.ang Earned Value - EV) pozwalają zaadresować te wyzwania, jednak ze względu na swoją złożoność mogą...
-
Treatment Wetland for Overflow Stormwater Treatment: The Impact of Pollutant Particles Size
PublicationThe problem of stormwater treatment in urban areas has become increas- ingly crucial. It has been widely recognized that both mechanical and biological treatment of stormwater is necessary to protect surface water against pollution. Moreover, technology must be applied to ensure effective treatment in changing hydraulic conditions and to serve, to the extent possible, as a retention volume. Treatment wetland (TW) could be...
-
Distribution and removal efficiency of heavy metals in two constructed wetlands treating landfill leachate
PublicationThe results of heavy metals (Fe, Mn, Zn, Ni, Cu, Cr, Pb, Cd) removal and partitioning between aqueous and solid phases at two wetlands (TWs) treating municipal landfill leachates are presented. One of the TWs is a surface flow facility consisting of 10 ponds. The other TW is a newly constructed pilot-scale facility consisting of three beds with alternately vertical and horizontal sub-surface flow. The metals concentrations were...
-
On the differential effect of temperature on the Nusselt-Rayleigh relationship in free convection
PublicationThe aim of and inspiration behind this paper was to explain the reasons, also observed by other researchers, of the discrepancy in the results of experimental free convection, which for small Rayleigh and Nusselt numbers in the initial phase of research can sometimes reach several hundred percent. These discrepancies decrease with increasing heating power and plate surface temperature, in proportion to the increase in Ra and Nu,...
-
Empirical Relationship Describing Total Convective and Radiative Heat Loss in Buildings
PublicationOn the basis of theoretical considerations of convective-radiative heat transfer, a relationship was developed enabling the total convective and radiative heat flux QC+R emitted from any object at tw and its surroundings at t∞ to be calculated from known values of the surface temperature of such an object, i.e., the known temperature difference Δt=tw - t∞ and average air temperature Tav. This relationship is applied to thermal...
-
Nonnegative solutions to nonlocal boundary value problems for systems of second-order differential equations dependent on the first-order derivatives
PublicationStosując tw. Avery-Petersona o punkcie stałym, podano warunki dostateczne na istnienie nieujemnych rozwiązań dla układów równań różniczkowych rzędu drugiego z argumentami opóźnionymi i wyprzedzonymi oraz warunkami brzegowymi zawierającymi całki Stieltjesa. Praca zawiera wiele przykładów.
-
Selections and approximations of convex-valued equivariant mappings
PublicationUdowodniono szereg twierdzeń o współzmienniczych selekcjach i aproksymacjach ciągłych, mierzalnych i typu Caratheodory'ego dla odwzorowań G-współzmienniczych o wartościach wypukłych, gdzie G jest grupą zwartą Liego. Tw. typu Michaela, Celliny, Browdera, Kuratowskiego-Ryll-Nardzewskiego, Castaing itd.
-
Analysis of unsteady flow forces on the thermowell of steam temperature sensor
PublicationIn this paper, 3D numerical analysis of unsteady flow forces acting on the measuring sheath of steam temperature is presented. According to that purpose, the CFD (Computation Fluid Dynamic [1]) approach has been used. The nonstationary of fluid acting on the measuring sheath such as: Strouhal frequency, amplitude of pressure, structure of vortex, peak of pressure, field of pressure, field of velocity etc. are studied analytically...
-
Application of multistage treatment wetlands as a buffer for effluent from Anammox treatment for reject water from centrifugation
PublicationAccording to the newest knowledge concerning TW technology multistage treatment wetland could be easily applied for ensuring stable and low concentration of biogenic compounds form the effluent of SBR reactor (with nitritation/annamox process) for treatment of digested sludge dewatering in side stream. The working condition and optimising of such MTW will be the issue of carried out investigation.
-
Positive solutions for fourth-order differential equations with deviating arguments and integral boundary conditions
PublicationBadane są problemy brzegowe dla równań różniczkowych rzędu czwartego z odchylonymi argumentami i z warunkami brzegowymi typu całkowego. Sformułowano twierdzenie dotyczące istnienia dodatnich rozwiązań takich problemów. W dowodzie korzystano z tw. Avery-Petersona o punktach stałych dla stożków. Podano przykład ilustrujący otrzymane wyniki.
-
Multiple solutions for a class of boundary-value problems with deviating arguments and integral boundary conditions
PublicationPraca dotyczy istnienia dodatnich rozwiązań dla równań różniczkowych rzędu drugiego z całkowymi warunkami brzegowymi i z odchylonymi argumentami typu wyprzedzonego. Korzystając z tw. Avery-Petersona dla stożków, podano warunki dostateczne na istnienie trzech dodatnich rozwiazań w/w problemów. Podano przykład pokazujący iż przyjęte załozenia są spełnione.
-
Natural convection in symmetrically heated vertical channels
PublicationThe study describes natural convection through a vertical channel, open on four sides and bound by two isothermal walls. Both balancing and infrared experimental investigations were performed in air (Pr = 0.71) to estimate the impact of channel width s and wall-to-ambient temperature difference (tw - t∞) on natural convective heat transfer, the formation of air flow patterns and the rate of flow pattern formation. The study was...
-
Infrared techniques for natural convection investigations in channels between two vertical, parallel, isothermal and symmetrically heated plates
PublicationThe effect of the gap width between two symmetrically heated vertical, parallel, isothermal plates on intensity of natural convective heat transfer in a gas (Pr = 0.71) was experimentally studied using the balance and gradient methods. In the former method heat fluxes were determined based on measurements of the voltage and electric current supplying the heaters placed inside the walls. In the latter, heat fluxes were calculated...
-
Resistance of Escherichia coli and Enterococcus spp. to selected antimicrobial agents present in municipal
PublicationIn this study, the susceptibility to erythromycin (E) and to trimethoprim/sulfamethoxazole (SXT) among isolates of Enterococcus spp. and Escherichia coli was tested, respectively. Both fecal indicators were detected and isolated from raw(RW) and treated wastewater (TW) as well as from samples of activated sludge (AS) collected in a local wastewater treatment plant (WWTP). Biodiversity of bacterial community in AS was also monitored...
-
Zaufanie w detalicznych transakcjach internetowych
PublicationAutor wprowadza rozróżnienie pomiędzy zaufaniem w relacji interpersonalnej (RI) i nieinterpersonalnej (RN). Odwołując się do analizy Dylematu Więźnia w teorii gier i przywołując teorię kooperacji B. Williamsa, autor pokazuje, że logiczna struktura zaufania powinna zostać uzupełniona przez nieegoistyczne mikro-motywacje. W detalicznym handlu elektronicznym istnieją dwie przeciwstawne tendencje: człowiek i technika. Technologia powoduje...
-
RNS reverse high-speed converter with quasi-regular structure based on the Chinese Remainder Theorem
PublicationPrzedstawiono dwie nowe architektury szybkiego konwertera z systemuresztowego do systemu binarnego oparte o chińskie tw. o resztach. Zastosowano nowe struktury 4-operandowych sumatorów modulo 2M. Pierwsza ze struktur oparta jest o wstępne sumowanie najstarszych bitów wektorów sumy i przeniesienia na wyjściu sumatora CSA, natomiast druga o bezpośrednie wykrywanie przekroczenia 2M. Konwerter wykorzystujący drugą ze struktur charakteryzuje...
-
Amorficzny krzem przyszłością fotowoltaiki?
PublicationPodstawowym źródłem energii dla Ziemi jest promieniowanie słoneczne. Wartość strumienia energii słonecznej, emitowanej w kierunku Ziemi wynosi 173 000 TW. Człowiek jest w stanie przetworzyć i zmagazynować energię promieniowania słonecznego do postaci użytecznej, przy czym najbardziej rozpowszechnionym nośnikiem energii jest energia elektryczna. Zamiana energii słonecznej na elektryczną możliwa jest dzięki wykorzystaniu efektu...
-
A Computational Analysis of the Aerodynamic and Aeromechanical Behavior of a Thermo-Well for Steam Temperature Measurement in a Steam Turbine
PublicationThe goal of the paper is twofold: firstly, it presents computational fluid dynamics analysis for finding maximum unsteady flow forces (and their frequencies) acting on a thermo-well for measuring steam temperature in a steam turbine control stage and secondly, it presents computational solid dynamics analysis of possibility of entry into resonance of the thermowell structure. There have been analyzed two cases of flow with changing...
-
Sewage gardens - constructed wetlands for single family households
PublicationDuring the last 30 years the increase of interest in low-cost decentralized and small wastewater treatment plants (WWTP) is observed in Europe. For this purpose sand filters, stabilization ponds, mini reactors with activated sludge, trickling filters and treatment wetlands are used. Among the listed facilities treatment wetlands (TWs) offer effective and reliable treatment efficiency, being at the same time low-cost and simple...
-
Nitrogen conversion during treatment of various type of wastewater in multistage treatment wetlands
PublicationThe objective of this investigation was to recognize nitrogen speciation during wastewater treatment in three multistage TWs (MTWs), which are assuming more a most effective in nitrogen removal than single stage TWs. Carried out investigations and analysis enable for determination of conditions, relationships and processes responsible for nitrogen conversions in subsequent stages of MTWs. In treated wastewater and reject water...
-
The role of SSVF and SSHF beds in concentrated wastewater treatment, design recommendation
PublicationThe return flows of reject water from sewage sludge dewatering alter the activated sludgeprocess in a conventional WWTP and increas TN concentration in final effluent from WWTPs.The objectives of the investigation carried out is to consider the application of sequential SS VFbeds and an SS HF bed for the treatment of highly polluted wastewater, namely reject waterfrom sewage sludge dewatering in a centrifuge (RWC). This paper aims...
-
Antibiotic resistance and prevalence of class 1 and 2 integrons in Escherichia coli isolated from two wastewater treatment plants, and their receiving waters (Gulf of Gdansk, Baltic Sea, Poland)
PublicationIn this study, antimicrobial-resistance patterns were analyzed in Escherichia coli isolates from raw (RW) and treated wastewater (TW) of two wastewater treatment plants (WWTPs), their marine outfalls (MOut), and mouth of the Vistula River (VR). Susceptibility of E. coli was tested against different classes of antibiotics. Isolates resistant to at least one antimicrobial agent were PCR tested for the presence of integrons. Ampicillin-resistant...
-
Treatment Wetland effluent quality improvement by usage sorbents of various origin
PublicationTWs are finding as low-cost and also effective system to treat domestic wastewater. The aim of this study is to find suitable adsorbing material for application in an additional treatment unit where treatment wetlands do not provide sufficient PO4 3- reduction level. Material M1 is a fine-grained by-product of thermal treatment of carbonate-siliceous rock (opoka) with high content of calcium carbonate CaCO3 in temperature 700°C....
-
Partitioning of heavy metals in sub-surface flow treatment wetlands receiving high-strength wastewater
PublicationThe retention of heavy metals at two pilot-scale treatment wetlands (TWs), consisting of two vertical flow beds (VSSF) followed by a horizontal flow bed (HSSF) was studied. The TWs received highstrength wastewater: reject waters from sewage sludge centrifugation (RW) and landfill leachate (LL). The concentrations of metals: Fe, Mn, Zn, Al, Pb, Cu, Cd, Co, Ni were measured in treated wastewater, substrate of the beds and in plant...
-
The forecasts-based instrument rule and decision making. How closely interlinked? The case of Sweden
PublicationResearch background: The Central Bank of Sweden declared in years 1999–2006 the implementation of the Svensson’s concept of inflation forecast targeting (IFT). It means that the repo rate decision-making process depends on the inflation forecasts. The concept evolved from the strict IFT with the decision-making algorithm called ‘the rule of thumb’ to the flexible IFT. Purpose of the article: The aim of...