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排序方式: 共有1665条查询结果,搜索用时 15 毫秒
881.
Remo Merijs‐Meri Janis Zicans Tatjana Ivanova Ivan Bochkov Madara Varkale Piotr Franciszczak Andrzej K. Bledzki Paulius Pavelas Danilovas Janis Gravitis Kristaps Rubenis Valentina Stepanova Janis Locs 《Polymer Engineering and Science》2019,59(12):2467-2473
Oat and spelt husks (OH and SH, respectively) lignocellulosic biomass derived fillers have been compared with commercial wood flour (WF) in respects to their morphology, chemical composition, bulk density, aspect ratio, and thermal stability. OH and SH have been obtained by both mechanical milling and steam explosion auto‐hydrolysis treatment at various processing conditions. Reinforcement efficiency of OH and SH derived lignocellulosic biomass fillers on the flexural properties of maleic acid‐grafted polypropylene (PPgMA) compatibilized polypropylene (PP) composites is compared with that of WF. The compatibilized PP composites have been manufactured by melt compounding. Flexural test specimens of the compatibilized PP composites have been manufactured by injection molding. It has been demonstrated that both the husks derived lignocellulose fillers can be used to improve flexural modulus and maximal flexural strength of PP, although its modifying effect is somewhat smaller in comparison to WF reinforcement, most probably due to higher cellulose content of the latter. Husks derived lignocellulose filler‐reinforced PP composites, however, demonstrate increased flexibility in comparison to WF‐filled systems. POLYM. ENG. SCI., 59:2467–2473, 2019. © 2019 Society of Plastics Engineers 相似文献
882.
Piotr Suchomski Zdzisaw Kowalczuk 《International Journal of Adaptive Control and Signal Processing》2002,16(3):177-191
A design problem of generalized predictive control (GPC) of plants characterized by discrete‐time models with a non‐zero transportation‐delay is considered. Conditions for the existence of the solution of the problem in terms of relevant design parameters (tuning knobs) are proposed and the system characteristics are discussed. Several design hints suitable for such plant models are proposed. Consequently, it is shown that by a suitable choice of the GPC tuning knobs a definite pre‐arrangement of the solvability, complexity, stability and quality (including robustness) of the resultant GPC control systems can be achieved. Some numerical examples are also given to illustrate the design problem and proposed methodology. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
883.
Systematic errors of an astable multivibrator based time-division active power converter are analyzed. Results of a computer simulation for sinusoidal and nonsinusoidal input signals are compared with test measurements of a standard converter. The paper shows that a conversion error of the power converter can be estimated from the harmonic content of the input waveforms. 相似文献
884.
Zusammenfassung Am Beispiel eines Lenksystems mit zwei doppeltwirkenden Hydraulikzylindern für Fahrzeuge mit Knickgelenk wird eine Methode
zur Prüfung aller m?glichen Strukturen von Stangenmechanismen dargestellt. Danach wird mit Hilfe der Polyoptimierung die Geometrie
des Getriebes bestimmt, das'den Konstruktions- und Einsatzbedingungen genügt. Die Methode der Polyoptimierung liefert dem
Konstrukteur, im Vergleich zu den verbreiteten Optimierungsmethoden mit einer Zielfunktion, praxisnahe Ergebnisse. Der angewendete
L?sungsweg zeigt neue M?glichkeiten für Mechanismen zur Lenkung von Fahrzeugen mit Knickgelenk. Diese L?sungen charakterisieren
günstige Leistungsparameter. 相似文献
885.
It is shown that the temperature coefficient of the drain current of the triode like a JFET/SIT/is proportional to the potential barrier height of the device for small current densities. At large current densities the drift velocity and the gate-source built in patential are responsible for the temperature dependence of the drain current. 相似文献
886.
887.
Paneth P 《Accounts of chemical research》2003,36(2):120-126
Enzymatic dehalogenation reactions are important for the bioremediation of the environment because of the increasing anthropogenic pollution with halogen-containing organic compounds. Chlorine kinetic isotope effects have been measured for four hydrolytic dehalogenases. On the basis of these isotope effects, several details of the mechanisms of the enzymatic dehalogenation reactions have been revealed. 相似文献
888.
Socha P Koletzko B Jankowska I Pawłowska J Demmelmair H Stolarczyk A Swiatkowska E Socha J 《Lipids》2002,37(10):953-957
Long-chain PUFA (LCP) deficiency is a frequent complication in cholestatic infants. We investigated the effects of LCP-supplemented
formula on EFA status in infants with cholestasis. Twenty-three infants with cholestasis (biliary atresia after surgery, 8;
intrahepatic cholestasis, 15) aged 1.9 to 4.9 mon (median 3.1 mon) were randomized to receive commercial infant formulas either
without LCP or with LCP from egg phospholipids for 1 mon. Liver tests, nutrient intakes, and plasma phospholipid FA (%w/w)
were determined at baseline and after intervention. At baseline, patients had high serum direct bilirubin levels (5.9 ± 3.0
mg/dL; mean ± SD), they were malnourished (body fat mass: 40 ± 13% of normal) and presented with PUFA deficiency [plasma phospholipid
PUFA: 28.43%w/w (26.56–30.53) in patients vs. 37.02%w/w (34.53–39.58) in controls; median (1st–3rd quartile)] with elevated
Mead acid and palmitoleic acid. LCP-supplemented (n=11 and-nonsupplemented groups (n=12) did not differ in age, indicators of liver function, and EFA status at baseline. After the intervention, LCP-supplemented
infants had higher levels of arachidonic acid [7.2 (5.9–8.8) vs. 4.2 (3.0–5.3) %w/w; P<0.001] and DHA [2.8 (2.2–3.2) vs. 1.6 (1.0–2.1) %w/w; P<0.05], accompanied by increased [BARS concentration: 1.9 (1.4–2.2) vs. 1.3 (1.1–1.6) nmol/mL; P<0.05]. We concluded that LCP-supplemented formulae improve LCP status of infants with severe cholestasis but may enhance
lipid peroxidation. 相似文献
889.
Point pattern matching is an important problem in computational geometry, with applications in areas like computer vision, object recognition, molecular modeling, and image registration. Traditionally, it has been studied in an exact formulation, where the input point sets are given with arbitrary precision. This leads to algorithms that typically have running times of the order of high-degree polynomials, and require robust calculations of intersection points of high-degree surfaces. We study approximate point pattern matching, with the goal of developing algorithms that are more efficient and more practical than exact algorithms. Our work is motivated by the observation that in practice, data sets that form instances of pattern matching problems are noisy, and so approximate formulations are more appropriate. We present new and efficient algorithms for approximate point pattern matching in two and three dimensions, based on approximate combinatorial distance bounds on sets of points, and via the use of methods from combinatorial pattern matching. We also present an average-case analysis and a detailed empirical study of our methods. 相似文献
890.
Jarosław Wypychowski Jarosław Pytliński Łukasz Skorwider Mirosław Nazaruk Krzysztof Benedyczak Michał Wroński Piotr Bała 《New Generation Computing》2004,22(2):147-156
In this paper we describe deployment of most important life sciences applications on the grid. The build grid is heterogenous
and consist of systems of different architecture as well as operating systems and various middleware. We have used UNICORE
infrastructure as framework for development dedicated user interface to the number of existing computational chemistry codes
and molecular biology databases. Developed solution allows for access to the resources provided with UNICORE as well as Globus
with exactly the same interface which gives access to the general grid functionality such as single login, job submission
and control mechanism.
Jarosław Wypychowski: He is a student at the Faculty of Mathematics and Computer Science, Warsaw University, Poland. He is involved in the development
of grid tools. He has been working as programmer in the private company.
Jarosław Pytliński, M.Sc.: He received his M.Sc. in 2002 from Department of Mathematic and Computer Science of Nicolaus Copernicus University in Torun.
His thesis on “Quantum Chemistry Computations in Grid Environment” was distincted in XIX Polish Contest for the best M.Sc.
Thesis of Computer Science. He also worked in Laboratory of High Performance Systems at UCI, Torun. His interests are Artificial
Intelligence and GRID technology.
Łukasz Skorwider, M.Sc.: He is programmer in the private pharmaceutical company. He obtained M.Sc. degree from the Faculty of Mathematics and Computer
Science N. Copernicus University. As graduate student he was involved in the development of grid tools for drug design. His
private and professional interest is Internet technology.
Mirosław Nazaruk, M.Sc.: He is a senior computer and network administrator at ICM Warsaw University. He provides professional support for the users
of the high performance facilities located at the ICM. He obtained M.Sc. in Computer Science from Warsaw University in 1991.
Before joining ICM, he was a member of technical staff at Institute of Applied Mathematics, Warsaw University.
Krzysztof Benedyczak: He is a student at the Faculty of Mathematics and Computer Science, N. Copernicus University, Torun, Poland. He is involved
in the development of grid tools.
Michał Wroński: He is a student at the Faculty of Mathematics and Computer Science, N. Copernicus University, Torun, Poland. He is involved
in the development of grid tools.
Piotr Bała, Ph.D.: He is an adiunkt at Faculty of Mathematics and Computer Science N. Copernicus University, Torun, Poland, and tightly cooperates
with ICM, Warsaw University. He obtained Ph.D. in Physics in 1993 in Institute of Physics, N. Copernicus University and in
2000 habilitation in physics. From 2001 he was appointed director of Laboratory of Parallel and Distributed Processing at
Faculty of Mathematics, N. Copernicus University. His main research interest is development and application of Quantum-Classical
Molecular Dynamics and Approximated Valence Bond method to study of enzymatic reactions in biological systems. In the last
few years, he has been involved in development of parallel and grid tools for large scale scientific applications. 相似文献