Filters
total: 3049
filtered: 1978
-
Catalog
Chosen catalog filters
displaying 1000 best results Help
Search results for: GLASS CEILING
-
Application of Cohen´s class time-frequency distributions in the Belousov-Zhabotinsky reaction analysis
PublicationPrzedstawiono rezultaty spektralnej analizy rejestrów Biełousowa-Żabotyńskiego za pomocą czasowo-częstotliwościowych metod analizy sygnałów należących do klasy Cohen´a. Przykładowy rejestr zmian potencjału elektrody bromo-selektywnej został poddany analizie z wykorzystaniem rozkładu Wignera-Ville´a oraz rozkładu stożkowego. Zastosowanie powyższych algorytmów pozwoliło na uzyskanie spektrogramów przedstawiających zależność pomiędzy...
-
Exact analytical scattering lengths for a class of long-range potentials with r(-4) asymptotics.
PublicationWyprowadzono analityczne wyrażenie dla długości rozpraszania dla pewnej klasy potencjałów zanikających asymptotycznie jak r do (-4). Wpływ rdzenia potencjału uwzględniono poprzez dwa parametry: promień rdzenia oraz krótkozasięgową długość rozpraszania.
-
A note on the Morse homology for a class of functionals in Banach spaces involving the 2p-area functional
PublicationIn this paper we show how to construct Morse homology for an explicit class of functionals involving the 2p-area functional. The natural domain of definition of such functionals is the Banach space W_0^{1,2p}(\Omega), where p > n/2 and \Omega \subet R^n is a bounded domain with sufficiently smooth boundary. As W_0^{1,2p}(\Omega) is not isomorphic to its dual space,critical points of such functionals cannot be non-degenerate...
-
Model angular distribution functions in CA3, CA4 and CA6 structural units of glassy systems
PublicationMetodą Monte Carlo wyliczono funkcje rozkładu kątów pomiędzykrawędziami w losowo deformowanych jednostkach strukturalnychCA_3, CA_4 i CA_6, gdzie C oznacza centralny kation,a A - wierzchołkowy anion. Uzyskane dane mogą być wykorzystanejako dane referencyjne do ilościowej oceny stopnia nieporządkuw materiałach symulowanych numerycznie, głównie szkłachtlenkowych. W pracy podano przykłady takiego zastosowania.
-
Ensemble Online Classifier Based on the One-Class Base Classifiers for Mining Data Streams
Publication -
New Class of Antimicrobial Agents: SBA-15 Silica Containing Anchored Copper Ions
Publication -
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.
-
The existence and multiplicity of heteroclinic and homoclinic orbits for a class of singular Hamiltonian systems in R^2
PublicationW niniejszej pracy badamy autonomiczne układy Hamiltona na płaszczyźnie z potencjałem, który ma punkt osobliwy x, globalne minimum równe zero osiągane w punktach a i b różnych od x oraz spełnia warunek typu Gordona w otoczeniu punktu osobliwego. Wykorzystując metody wariacyjne i pojęcie rotacji krzywej wykazaliśmy, że istnieją co najmniej dwa rozwiązania, które omijają punkt osobliwy i łączą {a,b} z {a,b}.
-
Synthesis, structure and application of a new class of Tr-podands derived in phase-transfer catalysis
Publication -
Size-dependent electronic properties of nanomaterials: How this novel class of nanodescriptors supposed to be calculated?
Publication -
Approximative sequences and almost homoclinic solutions for a class of second order perturbed Hamiltonian systems
PublicationIn this work we will consider a class of second order perturbed Hamiltonian systems with a superquadratic growth condition on a time periodic potential and a small aperiodic forcing term. To get an almost homoclinic solution we approximate the original system by time periodic ones with larger and larger time periods. These approximative systems admit periodic solutions, and an almost homoclinic solution for the original system...
-
Characterizing the Performance of <span class="sc">xor</span> Games and the Shannon Capacity of Graphs
PublicationIn this Letter we give a set of necessary and sufficient conditions such that quantum players of a two-party xor game cannot perform any better than classical players. With any such game, we associate a graph and examine its zero-error communication capacity. This allows us to specify a broad new class of graphs for which the Shannon capacity can be calculated. The conditions also enable the parametrization of new families of games...
-
Analytical calculations of scattering lengths for a class of long-range potentials of interest for atomic physics
PublicationWe derive two equivalent analytical expressions for an $l$th partial-wave scattering length $a_{l}$ for central potentials with long-range tails of the form % \begin{math} \displaystyle V(r)=-\frac{\hbar^{2}}{2m}\frac{Br^{n-4}}{(r^{n-2}+R^{n-2})^{2}} -\frac{\hbar^{2}}{2m}\frac{C}{r^{2}(r^{n-2}+R^{n-2})}, \end{math} % ($r\geqslant r_{s}$, $R>0$). % For $C=0$, this family of potentials reduces to the Lenz potentials discussed in...
-
Heterogeneity of national accounting systems, world-class universities and financial resources: What are the links?
PublicationThis study investigates the relationship between university financial resources, applied accounting systems, and the place of a university in the Shanghai Ranking. We find a strong relationship between the financial resources under the control of a world-class university and the position of that university in the highest tier of the global ranking. We propose a model (available online) to predict a university’s tier in the ranking...
-
Applicability of glass fiber as a support material for generation of gase ous standard mixtures using thermal decomposition of the surface compound. Calibration of analytical equipment.
PublicationW pracy przedstawiono technikę sporządzania gazowych mieszanin wzorcowych(składnikiem mierzonym był eten) w oparciu o termiczny rozkład związków powierzchniowych. Jako nośnik dla związku powierzchniowego zastosowano włókno szklane. W temperaturze 245 stopni Celsjusza związek powierzchniowy ulega rozkładowi bądź przegrupowaniu uwalniając znaną ilość analitu (etenu). Technika ta umożliwia sporządzanie gazowych mieszanin...
-
Polyhydric SiO2 coating assistant to graft organophosphorus onto glass fabric for simultaneously improving flame retardancy and mechanical properties of epoxy resin composites
Publication -
The Application of Granulated Expanded Glass Aggregate with Cement Grout as an Alternative Solution for Sub-Grade and Frost-Protection Sub-Base Layer in Road Construction
PublicationThe purpose of the research was to assess the possibility of using granulated expanded glass aggregate (GEGA) with cement grout as a replacement of a sub-grade and frost-protection layer, made of natural fine aggregates (NATU), stabilized with a hydraulic binder. Instead of traditional parts of the road construction, such as the sub-grade and frost-protection layer with the application of fine aggregate, stabilized with cement,...
-
When Membership Gives Strength to Act: Inclusion of the Group Into the Self and Feeling of Personal Agency
Publication -
Nucleate pool boiling heat transfer from small horizontal smooth tube bundles
PublicationPrzedstawiono wyniki pomiarów współczynnika przejmowania ciepła podczas wrzenia wody destylowanej, metanolu i R141b na poziomym pęku rur gładkich, który składał się z 19 rurek, ogrzewanych elektrycznie, w układzie przestawionym i podziałce 1.7d oraz 2.0d. Wyznaczono również wartości współczynnika wpływu pęku. Podano równanie korelacyjne do obliczania średniego współczynnika przejmowania ciepła
-
A simplified energy dissipation based model of heat transfer for post-dryout flow boiling
Publicationmodel for post dryout mist flow heat transfer is presented based on considerations of energy dissipation in the flow. The model is an extension of authors own model developed earlier for saturated and subcooled flow boiling. In the former version of the model the heat transfer coefficient for the liquid singlephase convection as a reference was used, due to the lack of the appropriate model for heat transfer coefficient for the...
-
A study of jet impingement cooling enhancement by concave and convex heat sink shape modifications
PublicationThe rising demand for efficient cooling technologies is a strong driver of extensive research in this area. This trend is particularly strong in turbines and microprocessors technology. Presented study is focused on the jet impingement cooling concept, which is used in various configurations for many years. The potential of the heat sink shape modification is not yet fully explored. Available literature suggests that average Nusselt...
-
Heat exchange enhancement of jet impingement cooling with the novel humped-cone heat sink
PublicationJet impingement cooling technology is applicable to control temperature of devices, where very high heat flux is generated within a small area. This paper is about the improvement of the jet impingement cooling efficiency by the heat sink geometry modification. Two reference cases were sourced from the literature – flat heat sink and modified one with cone in the jet stagnation region. Such a change improves cooling capability...
-
Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper are presented the results of calculations using authors own model to predict heat transfer coefficient during flow boiling for carbon dioxide. The experimental data from various researches were scrutinised conducted for a full range of quality variation and wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The work shows the importance of taking into account surface...
-
Pipelined sceling of signed residue numbers with the mixed-radix conversion in the programmable gate array
PublicationIn this work a scaling technique of signed residue numbers is proposed. The method is based on conversion to the Mixed-Radix System (MRS) adapted for the FPGA implementation. The scaling factor is assumed to be a moduli product from the Residue Number System (RNS) base. Scaling is performed by scaling of terms of the mixed-radix expansion, generation of residue reprezentation of scaled terms, binary addition of these representations...
-
Circumferential temperature distribution during pool boiling of R 141b onhorizontal modified tubes.
PublicationZaproponowano własną bierną, metodę intensyfikacji przejmowania ciepła w obszarze górnej tworzącej rurki w celu zminimalizowania obwodowego rozkładu temperatury. Metoda polega na naniesieniu aluminiowej warstwy porowatej tylko na części powierzchni rurki - właśnie w obszarze górnej tworzącej.
-
Flow distribution and heat transfer in minigap and minichannel heat exchangers during flow boiling
PublicationThe topic of boiling heat transfer in miniscale geometries has focused the ever increasing interest of researchers in recent years. However, most of the works are related to mini- and microchannels and much less to minigaps. Meanwhile, minigaps allow for more comprehensive experimental studies, i.e. flow visualisations due to the flat, two-dimensional configuration of the flow. The results of the experimental investigations of...
-
Water Demineralization by Membrane Distillation Utilizing Cooling Water From Municipal Waste Incinerator
Publication -
Effect on Phytochemical Content and Microbial Contamination of Actinidia Fruit after Shock Cooling and Storage
Publication -
The effects of textile reinforcements on the protective properties of self-healing polymers intended for safety gloves
Publication -
Flavoenzyme-catalyzed redox cycling of hydroxylamino- and amino metabolites of 2,4,6-trinitrotoluene: implications for their cytotoxicity
Publication -
A new procedure for the determination of distillation temperature distribution of high-boiling petroleum products and fractions
PublicationThe distribution of distillation temperatures of liquid and semi-fluid products, including petroleum fractions and products, is an important process and practical parameter. It provides information on properties of crude oil and content of particular fractions, classified on the basis of their boiling points, as well as the optimum conditions of atmospheric or vacuum distillation. At present, the distribution of distillation temperatures...
-
Interaction of Acoustic and Thermal Modes in the Gas with Nonequilibrium Chemical Reactions: Possibilities of Acoustic Cooling
PublicationNonlinear generation of thermal mode during propagation of dominative sound in a chemically reacting gas is considered. The dynamic equation of excess temperature associated with the thermal mode is derived. It is instantaneous and includes quadratic nonlinear acoustic source reflecting the nonlinear character of interaction between acoustic and non-acoustic types of gas motion. Both periodic and aperiodic sound may be considered...
-
The effect of boiling in a thermosyphon on surface tension and contact angle of silica and graphene oxide nanofluids
Publication -
Numerical investigations of the engine cooling system in a small power vesel pod propulsion system
PublicationThe development of electronics and electrotechnology enabled to put electric motors of the alternating current in the pod and to use them for the main drive of ships. A lot of heat which must be picked up from the system is a problem which is turning up at applying the system of this type. Many big ships lately contended with these problems. Building the small propeller for the boat powered with solar power we decided to check...
-
Evaluation of turning with different cooling-lubricating techniques in terms of surface integrity and tribologic properties
Publication -
Non-adiabatic Effects in Pressure Drop Calculations in Flow Boiling and Flow Condensation in Minichannels
PublicationConsiderations presented in the paper relate both to the case of flow boiling and flow condensation in conventional channels as well as small diameter ones. Authors devoted all the possible attention that the modeling presented is applicable to the whole range of quality variation in both cases of condensation and boiling. The form of two-phase flow multiplier, which is a major factor in modeling presented here, should be capable...
-
Determination of dryout localization using a five-equation model of annular flow for boiling in minichannels
PublicationDetailed studies have suggested that the critical heat flux in the form of dryout in minichannels occurs when the combined effects of entrainment, deposition, and evaporation of the film make the film flow rate go gradually and smoothly to zero. Most approaches so far used the mass balance equation for the liquid film with appropriate formulations for the rate of deposition and entrainment respectively. It must be acknowledged...
-
Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper presented are the results of calculations using authors own model to predict heat transfer coefficient during flow boiling of carbon dioxide. The experimental data from various resea rches were collected. Calculations were conducted for a full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The results show the importance of taking into...
-
Pool Boiling of Water–Al2O3 and Water–Cu Nanofluids Outside Porous Coated Tubes
PublicationThis paper deals with pool boiling ofwater–Al2O3 and water–Cu nanofluids on porous coated, horizontal tubes. Commercially available stainless-steel tubes having 10 mm outside diameter and 0.6 mm wall thickness were used to fabricate a test heater. Aluminum porous coatings 0.15 mm thick with porosity of about 40% were produced by plasma spraying. A smooth tube served as a reference tube. The experiments were conducted under different...
-
Thermal-hydraulic issues of flow boiling and condensation in organic Rankine cycle heat exchangers
PublicationW pracy przedstawiono szereg zagadnień cieplno-przepływowych podczas wrzenia i kondensacji w przepływie w wymiennikach ciepła obiegu ORC. Uwzględniono przemiany fazowe. Analizowano zagadnienia stabilności pracy wymienników oraz ich dynamikę
-
A semi-empirical model for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the present study the attention was focused on the influence of reduced pressure on the predictions of heat transfer during flow boiling at the extensive range of pressures. The results of calculations were to test the sensitivity of the in-house flow boiling model with respect to the selection of the appropriate two-phase flow multiplier, which is one of the distinctive elements of that model. For this purpose a few two-phase...
-
Experimental study and comparison with predictive methods for flow boiling heat transfer coefficient of HFE7000
PublicationThis article describes an experimental study of flow boiling of HFE7000 inside a smooth vertical channel. The investigation has been carried out in a circular stainless-steel tube with an inner diameter of 2.3 mm. The data have been collected for the applied heat fluxes q ranging from 61 to 205 kW/m2, the mass flux G ranging from 214 to 1006 kg/(m2 s), the saturation temperature Tsat ranging from 30 to 54 °C and the full range...
-
Consideration of Pseudo Strain Energy in Determination of Fatigue Life and Microdamage Healing of Asphalt Mastics
PublicationRest periods between cyclic loads can lead to recovery of damage and extension of fatigue life. This phenomenon is referred to as healing. Healing is clearly observed in bituminous materials, such as asphalt mastics, which belong to the components of asphalt mixtures. Due to the nature of road pavement traffic loading, which is characterized by series of intermittent pulses with rest periods, consideration of healing is necessary...
-
Experimental investigation on heat pipes supported by soy wax and lauric acid for electronics cooling
PublicationThis paper presents an experimental study of heat pipes for electronics cooling that were supported by energy storage materials (i.e. phase change materials - PCMs) coated at the adiabatic section. The PCMs utilized included two materials, namely lauric acid and soy wax, the latter being considered as a more cost-effective alternative. The study focused on three different powers: 20 W, 25 W, and 30 W. Both heating, cooling, and...
-
Influence of porous coating on heat transfer during flow boiling of R22, R134a and R407C
PublicationPrzedstawiono wpływ pwłoki porowatej w pozionej rurce podczas wrzenia w przepływie i spadku ciśnienia czynników chłodniczych R22, R134a i R407C.
-
Studies on Aminoanthraquinone-Modified Glassy Carbon Electrode: Synthesis and Electrochemical Performance toward Oxygen Reduction
PublicationIn this paper, 9,10-anthraquinone (AQ) derivative-modified glassy carbon (GC) electrodes were studied towards the electrochemical reduction of oxygen in aqueous and non-aqueous solutions. The reaction of 1-chloro-9,10-anthraquinone with aliphatic diamines was applied for the synthesis of amino-9,10-anthraquinone derivatives. The obtained AQ derivatives were grafted onto the surface of glassy carbon electrodes by electropolymerisation...
-
Intra-subject class-incremental deep learning approach for EEG-based imagined speech recognition
PublicationBrain–computer interfaces (BCIs) aim to decode brain signals and transform them into commands for device operation. The present study aimed to decode the brain activity during imagined speech. The BCI must identify imagined words within a given vocabulary and thus perform the requested action. A possible scenario when using this approach is the gradual addition of new words to the vocabulary using incremental learning methods....
-
Studies on Aminoanthraquinone-Modified Glassy Carbon Electrode: Synthesis and Electrochemical Performance toward Oxygen Reduction
PublicationIn this paper, 9,10-anthraquinone (AQ) derivative-modified glassy carbon (GC) electrodes werestudied towards the electrochemical reduction of oxygen in aqueous and non-aqueous solutions. The reaction of 1-chloro-9,10-anthraquinone with aliphatic diamines was applied for the synthesis of amino-9,10-anthraquinone derivatives. The obtained AQ derivatives were grafted onto the surface of glassy carbon electrodes by electropolymerisation...
-
Establishment, Growth, and Yield Potential of the Perennial Grass Miscanthus × Giganteus on Degraded Coal Mine Soils
Publication -
ANYTIME POLYNOMIAL HEURISTIC ALGORITHM FOR PARTITIONING GROUPS OF DATA WITH PRESERVING CLASS PROPORTIONS FOR CROSS-VALIDATION
PublicationThe article describes a problem of splitting data for k-fold cross-validation, where class proportions must be preserved, with additional constraint that data is divided into groups that cannot be split into different cross-validation sets. This problem often occurs in e.g. medical data processing, where data samples from one patient must be included in the same cross-validation set. As this problem is NP-complete, a heuristic...