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91.
High-order finite elements are usually defined by means of certain orthogonal polynomials. The performance of iterative solution methods depends on the condition number of the system matrix, which itself depends on the chosen basis functions. The goal is now to design basis functions minimizing the condition number, and which can be computed efficiently. In this paper, we demonstrate the application of recently developed computer algebra algorithms for hypergeometric summation to derive cheap recurrence relations allowing a simple implementation for fast basis function evaluation. 相似文献
92.
János Varga Sándor Kocsubé Beáta Tóth Tibor Bartók 《International journal of food microbiology》2012,152(1-2):46-48
93.
The ground state properties of helium mixed clusters 3He2,3,4
4He2, 3He2,3,4
4He3, 3He2,3,4
4He4, 3He2,3
4He5, consisting of up to eight helium atoms are studied using variational and diffusion Monte Carlo calculations. For clusters with three and four 3He atoms released-node diffusion Monte Carlo method is used. Our calculations show that, within errorbars, clusters 3He3,4
4He2 have the same binding energy as the cluster 3He2
4He2, and that 3He3
4He3 has the same binding energy as 3He2
4He3. The clusters 3He3,4
4He2 and 3He3
4He3 are in states in which one or two 3He atoms are far away from the rest of the system. Other considered clusters are bound. In particular, we have shown the stability of the cluster 3He4
4He3, which was previously considered unstable. The calculations are performed using several different interatomic potentials and the conclusions concerning stability are insensitive to the particular form of the interaction potential. We compare our results with the recent experiment and other theoretical calculations. 相似文献
94.
P Verlé NT Ruyen NT Huong NT Be A Kongs P Van der Stuyft M Coosemans 《Canadian Metallurgical Quarterly》1998,3(10):833-836
We tested a modified Beilstein method for detecting pyrethroids on bednets under laboratory conditions using an emulsifiable concentrate of permethrin (50 EC) for viability as a simple standardized field test and to judge its reliability for detecting different insecticide doses. At the recommended doses of permethrin (0.5 g/m2), sensitivity was near 100%, even when small pieces of fabric were tested and time of extraction was limited. In unwashed nets sensitivity stayed high (80-95%) down to 0.1 g active ingredient/m2. In untreated nets false positives were rare (0-2%). The test could become a valuable tool in vector control programmes: it is cheap, easy to learn and to perform. The Lot Quality Assurance Sampling method, using an upper and lower performance threshold, could be applied for monitoring the impregnation campaigns. 相似文献
95.
96.
The effect of traditional production methods on microbial,physico‐chemical and sensory properties of ‘Slovenská bryndza’ Protected Geographical Indication cheese 下载免费PDF全文
Boris Semjon Anna Reitznerová Zuzana Poláková Jana Výrostková Jana Maľová Beáta Koréneková Eva Dudriková Viera Lovayová 《International Journal of Dairy Technology》2018,71(3):709-716
Bryndza is a natural, white, mature and spreadable kind of cheese, and since 2008, it has been manufactured in specified mountainous areas of the Slovak Republic with Protected Geographical Indication. The aim of this work was to provide useful information about the microbial, physico‐chemical and sensory characteristics of bryndza, taking into consideration the variabilities related to the traditional methods of production technology of three bryndza cheese varieties. Statistically significant differences were observed in bryndza cheese production methods in chemical parameters of NaCl and malondialdehyde content (P < 0.05) and in the microbial presence of Enterococcus spp. (P < 0.001) and Staphylococcus spp. (P < 0.01). 相似文献
97.
借助于数值方法中的拟合手段来构造多项式函数,通过建立两个关键变量之间的正、逆向数学关系,对喷浆机器人大臂机构的运动轨迹进行了规划,并利用仿真分析的结果对其进行了检验. 相似文献
98.
在机械设计中 ,利用CAD接口进行三维建模生成三维实体。本文主要介绍了三维实体建模的意义及方法 ,同时给出实例得到三维实体建模在设计中的应用 相似文献
99.
100.
Mačanga J Koréneková B Nagy J Marcinčák S Popelka P Kožárová I Korének M 《Meat science》2011,88(4):701-704
In this study changes in the concentrations of lactate, phosphates, and pH values of water extracts of muscles of transported and hunted rabbits during ripening were determined. Concentrations of lactate were higher in the muscles of hunted rabbits. The highest differences were obtained 24h after kill/hunt. Concentrations of lactate in the muscles of hunted rabbits were decreasing, while in the muscles of transported rabbits we observed it to increase in the 7th day and then decrease in the 14th day. Higher concentrations of phosphates were found in the muscles of transported wild rabbits. During the ripening process concentrations of phosphates were decreasing in muscles of both groups. Muscles of hunted rabbits had lower pH values during the whole ripening process. Our research showed that concentrations of lactate, phosphates and pH value post-mortem depended on the perimortal situations. 相似文献