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91.
Deviation in Fat Content of Different Oil Yielding Plants To get an insight into the factors and their intensity causing deviation in the oil content of some of the oil yielding plants, the deviating components of winter rape, sunflower, linseed, soybean and mustard species were determined with the help of variance analysis, carried out in widely different experiments with cultivated material as well as in value and control tests. The greatly varying extreme values of the fat content resulted from environmental factors, yearly and local effects as well as genetically dependent family and species differences. The standard deviations show quite clearly that the effects of year, location and species are different in different oil yielding plants. 相似文献
92.
Orna?Grumberg Tamir?HeymanEmail author Assaf?Schuster 《Formal Methods in System Design》2005,26(2):197-219
In this paper we propose a distributed symbolic algorithm for model checking of propositional μ-calculus formulas. μ-calculus is a powerful formalism and μ-calculus model checking can solve many problems, including, for example, verification of (fair) CTL and LTL properties. Previous works on distributed symbolic model checking were restricted to reachability analysis and safety properties. This work thus significantly extends the scope of properties that can be verified distributively, enabling us to use them for very large designs.The algorithm distributively evaluates subformulas. It results in sets of states which are evenly distributed among the processes. We show that this algorithm is scalable and therefore can be implemented on huge distributed clusters of computing nodes. The memory modules of the computing nodes collaborate to create a very large memory space, thus enabling the checking of much larger designs. We formally prove the correctness of the parallel algorithm. We complement the distribution of the state sets by showing how to distribute the transition relation.This research was supported by The Israel Science Foundation (grant number 111/01-2) and by a grant from Intel Academic Relations. 相似文献
93.
Rate-distortion optimal video summary generation. 总被引:1,自引:0,他引:1
Zhu Li Guido M Schuster Aggelos K Katsaggelos Bhavan Gandhi 《IEEE transactions on image processing》2005,14(10):1550-1560
The need for video summarization originates primarily from a viewing time constraint. A shorter version of the original video sequence is desirable in a number of applications. Clearly, a shorter version is also necessary in applications where storage, communication bandwidth, and/or power are limited. The summarization process inevitably introduces distortion. The amount of summarization distortion is related to its "conciseness," or the number of frames available in the summary. If there are m frames in the original sequence and n frames in the summary, we define the summarization rate as m/n, to characterize this "conciseness". We also develop a new summarization distortion metric and formulate the summarization problem as a rate-distortion optimization problem. Optimal algorithms based on dynamic programming are presented and compared experimentally with heuristic algorithms. Practical constraints, like the maximum number of frames that can be skipped, are also considered in the formulation and solution of the problem. 相似文献
94.
Properties are given for as-deposited and heat-treated carbon-felt, carbon-matrix composites infiltrated at deposition temperatures of 1100 and 1400°C, and pressures of 20 and 630 Torr. A thermal stress figure of merit was calculated for each material, with the heat-treated composite infiltrated at 1400°C and 630 Torr yielding the highest value. As with most graphitizing carbon materials, heat-treatment resulted in a decrease of the flexural strengths and moduli. The strength-to-modulus ratios, however, increased, being highest for deposition conditions of 1400°C and 630 Torr. Heat-treatment also resulted in an increase in thermal conductivity and a decrease in thermal expansion. These changes were related to the degree of crystallinity and to the formation of cracks within the matrix. 相似文献
95.
R Schuster 《Canadian Metallurgical Quarterly》1976,29(4):161-164
The deformities observed in 2 Clydesdale foals are described. Both had abnormal joint positions in the forelimbs and discrepancies in the symmetry of the vertebral column. The changes were only mild in one case but extreme in the other where it was accompanied by torticollis, scoliosis and vertebral fusion. A comparison is made with deformities described in the contracted foal syndrome and some of the developmental implications discussed. 相似文献
96.
Investigations on the Effectiveness of Preservatives in Anion Active Surfactants The preserving action of five preservatives was tested at pH values of 6, 7 and 8 in 10% solutions of the anion active surfactants sodium lauryl sulfate, protein-fatty acid condensate and sodium laurylether sulfate. It was found that the three difficultly water-soluble compounds p-chloro-m-cresol, pentachlorophenol and the combined methyl and ethyl esters of the p.H.B. esters are ineffective at usual concentrations. Both of the watersoluble preservatives polyoxymethyleneglycol and chloroacetamide were effective. Furthermore, it was observed that the preservative action of chloroacetamide is enhanced by anion active surfactants. The inactivation of the difficulty watersoluble preservatives is traced back to the solubilization of these compounds by the micelle of the anion active surfactants. 相似文献
97.
Summary Gas chromatography has been employed to determine partial molar free energies of sorption, C1
s, as well as partial molar free energies of mixing, C1
, of atactic poly(styrene) with linear and branched alkanes (C6-C9), alkenes (C8), cyclohexane and alkylbenzenes (Ph-H to PhC6H13) within the temperature range from 403 to 463 K. The influence of nature and constitution of the solute molecule on sorption and mixing properties in poly(styrene) are discussed in terms of the competing group contributions of the components. Knowledge of this influence may be transduced to understand polymer-polymer compatibility. The cohesive energy density concept has been used to calculate the infinite dilution solubility parameter for the polymer, with the aid of G
1
. From the high temperature range the HILDEBRAND parameter 2 was extrapolated to 298 K. The value obtained, 9.14, indicates that gas chromatography is an promising alternative to the conventional methods for determination of the solubility parameter for polymers.Herrn Prof. Dr. R. C. Schulz zu seinem 65. Geburtstag herzlichst gewidmet 相似文献
98.
Carl Seelkopf und Hugo Schuster 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1957,106(3):177-187
Zusammenfassung Es wird eine geeignete Extraktionsmethode zur Isolierung des Pilzeiweißes sowie seine Abtrennung von den Zuckern und Mineralstoffen beschrieben. Ein kombiniertes Hydrolyseverfahren erlaubt es, die einzelnen Aminosäuren möglichst verlustfrei in Lösung zu bekommen. Der qualitative Nachweis der Aminosäuren erfolgte mit Hilfe der zweidimensionalen Papierchromatographie. Zur quantitativen Bestimmung dient die eindimensionale Chromatographie auf gepuffertem Papier, wobei zur Ermittlung der Farbintensitäten in jedem Versuch eine Aminosäuremischung bekannter Zusammensetzung mitläuft. Bei der Mehrzahl der Aminosauren wird die Intensität der Ninhydrinfärbung nach dem Ablösen vom Papier im Pulfrich-Photometer gemessen. Besondere Farbreaktionen werden zur Bestimmung des Tryptophans, Prolins, Histidins und Cystins herangezogen.Anhand des beschriebenen Extraktionsverfahrens wird das wahre Eiweiß in den untersuchten Pilzen bestimmt. Hierbei werden wesentlich niedrigere Werte gefunden, als sonst in der Literatur angegeben werden. Die Eiweißverluste beim Trocknen und Lagern bewegen sich in mäßigen Grenzen. Qualitativ werden alle wichtigen Aminosäuren im Pilzeiweiß gefunden. Die quantitative Verteilung der Aminosäuren ist innerhalb der einzelnen Pilzarten oft recht unterschiedlich. Hingegen kann bei ein und derselben Pilzsorte kein großer Unterschied in der quantitativen Zusammensetzung des Eiweilßes der jungen oiler alten Pilze gefunden werden.Das Eiweiß der eiweißreichsten Pilze (Champignon, Steinpilz) steht in seinem biologischen Wert zwischen pflanzlichem and tierischem Eiweiß. Alle Speisepilze sind im Vergleich zum Weizen- und Erbseneiweiß arm an Isoleucin und mit Ausnahme des Steinpilzes auch arm an Methionin.Auszug aus der Dissertation vonHugo Schuster: Qualitative and quantitative Aminosäurebestimmung der wiehtigsten Speisepilze . Univ. Würzburg 1956. 相似文献
99.
Recently, Chinn et al. [10] presented lower bounds for store-and-forward permutation routing algorithms on the n \times n mesh with bounded buffer size and where a packet must take a shortest (or minimal ) path to its destination. We extend their analysis to algorithms that are nearly minimal. We also apply this technique to
the domain of hot potato algorithms, where there is no storage of packets and the shortest path to a destination is not assumed
(and is in general impossible). We show that ``natural' variants and ``improvements' of several algorithms in the literature
perform poorly in the worst case. As a result, we identify algorithmic features that are undesirable for worst-case hot potato
permutation routing.
Recent works in hot potato routing have tried to define simple and greedy classes of algorithms. We show that when an algorithm
is too simple and too greedy, its performance in routing permutations is poor in the worst case. Specifically, the technique
of [10] is also applicable to algorithms that do not necessarily send packets in minimal or even nearly minimal paths: it
may be enough that they naively attempt to do so when possible. In particular, our results show that a certain class of greedy
algorithms that was suggested recently by Ben-Dor et al. [6] contains algorithms that have poor performance in routing worst-case
permutations.
Received August 24, 1995; revised May 27, 1997. 相似文献
100.