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排序方式: 共有593条查询结果,搜索用时 31 毫秒
31.
Primary biliary cirrhosis associated with cholangiocarcinoma 总被引:1,自引:0,他引:1
32.
C Kawanishi Y Shimoda J Fujimaki H Onishi K Suzuki T Hanihara N Sugiyama K Kosaka 《Canadian Metallurgical Quarterly》1998,160(1):102-104
Traumatic injuries of arteries lead to acute bleeding or ischemia. In the hand, which is perfused by two arteries, this symptom could be missed. The hypothenar hammer syndrome is a traumatic occlusion of the distal arteria ulnaris. Dependent on the mechanism of the trauma the clinical symptoms may appear late. A specific angiographic or duplex sonographic diagnostic investigation is necessary to show the arterial occlusion. There is no proven therapeutic procedure. Exact diagnosis of the occlusion as an effect of the trauma is important for the patient and is the basis of any therapeutic intervention. 相似文献
33.
Goal theory postulates that harder goals lead to higher performance than do easier goals. The present study tested the prediction, based on expectancy valence theory, that this would be true only if the payoff for succeeding at the harder goal is sufficiently greater than the alternatives to compensate for its greater difficulty. 63 undergraduates were each given an easy and a hard task/goal, requiring the comparison of paired sets of 3-digit numbers. Expectancy theory measures for the 2 goals were obtained from Ss. Performance was higher for the hard goal than for the easy goal, supporting the goal theory postulate. Force was also higher for the hard goal than for the easy goal. In addition, force change across the 2 goals was associated with performance change, supporting the conclusion that expectancy valence theory can predict the goal theory postulate. The valence of goal attainment was higher for the hard goal than for the easy goal. Valence change across the 2 goals was associated with performance change to a greater degree than was expectancy change, suggesting that the attained performance difference can be attributed to the valence difference. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
The role of abduction in chance discovery 总被引:1,自引:0,他引:1
Recently, researches on discovery science and knowledge discovery have been carried out in various fields. Basically they
are types of learning that learn tendencies from the sets of data of the same or similar categories. In this sense, discovery
is to discover the tendencies. As a result, they cannot predict the events that are different from the trend. On the other
hand, abduction is thought of as an explanatory reasoning. Indeed, abduction is a reasoning to generate hypotheses to explain
an observation. However, the original meaning of abduction was to discover new things that cannot be known in a simple way.
In this paper, abduction is defined using the original definition that discovers something that cannot be easily predicted.
Then, this paper shows a role of abduction that can suggest or foresee the events that are different from the trend. In fact,
Abductive Analogical Reasoning that can generate new hypotheses is adopted to solve the problem.
Akinori Abe, Ph.D.: He obtained his Doctor of Engineering (Ph.D) from the University of Tokyo in 1991, with a thesis entitledA Fast Hypothetical Reasoning System using Analogical Case. His main research interests are abduction (hypothetical reasoning), analogical reasoning, chance dicovery and language sense
processing. He is a member of the Planning Committee of the New Generation Computing. He worked in NTT MSC (Malaysia) from
2000 to 2002. Currently, he works in ATR. 相似文献
35.
Y. Inatomi F. Onishi K. Nagashio K. Kuribayashi 《International Journal of Thermophysics》2007,28(1):44-59
The density and thermal conductivity of a high-purity silicon melt were measured over a wide temperature range including the
undercooled regime by non-contact techniques accompanied with electromagnetic levitation (EML) under a homogeneous and static
magnetic field. The maximum undercooling of 320 K for silicon was controlled by the residual impurity in the specimen, not
by the melt motion or by contamination of the material. The temperature dependence of the measured density showed a linear
relation for temperature as: ρ(T) = 2.51 × 103−0.271(T−T
m) kg · m−3 for 1367 K < T < 1767 K, where T
m is the melting point of silicon. A periodic heating method with a CO2 laser was adopted for the thermal conductivity measurement of the silicon melt. The measured thermal conductivity of the
melt agreed roughly with values estimated by a Wiedemann–Franz law. 相似文献
36.
Yoshihito Honsho Atsushi Asano Shu Seki Takeyoshi Sunagawa Akinori Saeki 《Synthetic Metals》2009,159(9-10):843-846
Intra-molecular mobility of positive charge carriers in poly(n-hexyl-[S]-2-methylbutylsilane) (PHMBS) films doped with N,N′-bis(2,5-di-tert-buthylphenyl)-3,4,9,10-perylenedicarboximide (PDI) is studied by time-resolved microwave conductivity (TRMC) measurements. PHMBS with optically active side chains has a rod-like tightly locked Si catenation with unlikely long persistence length compared with conventional dialkyl-substituted polysilanes. It was found that PDI is a suitable electron acceptor for PHMBS as it provides the high product of photo carrier generation yield ? as ~0.08% under an excitation at 355 nm. The efficient electron transfer reaction from PHMBS to PDI gives clear conductivity transients ascribed to the positive charges on the Si catenation of PHMBS by TRMC measurements. The estimated value of isotropic mobility along the tightly locked Si catenation is 0.36 cm2 V?1 s?1, suggesting the presence of mobile holes on the backbones of PHMBS. 相似文献
37.
The water wettability and non-wettability onto various kinds of polymers, which have so far been macroscopically described by the water contact angle, were investigated using the molecular orbital theory. An atomistic model consisting of an H2O molecule and a selected polymer crystal surface was analyzed in the isolated and the physisorbed states. The degree of interaction between the water molecule and the polymer surface was evaluated by considering the change of Mulliken charge at the oxygen site in the water molecule, and also the work of adhesion during the physisorption process. Such energetic quantities for several polymers were compared with the macroscopic water wettability/non-wettability. We found fairly good agreement between these approaches for the highly non-wettability polymers. 相似文献
38.
Yuko Hamabe Ryoko Matsuura Akinori Jyo Masao Tamada Akio Katakai 《Reactive and Functional Polymers》2009,69(1):1-8
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin. 相似文献
39.
40.
The γ‐cyclodextrin (γ‐CD) inclusion complexes (ICs) with four kinds of polyolefin (PO) as guest molecules were prepared. The crystallization behavior of isotactic polypropylene (iPP) blended with the γ‐CD and γ‐CD–PO ICs was investigated by differential scanning calorimetry, polarized optical microscopy, and light scattering. The iPP blended with the ICs was found to exhibit higher crystallization temperature (TC), smaller spherulites, and faster crystallization rate than those of neat iPP, indicating that the ICs play a role of nucleating agent on the crystallization of iPP and induce accelerated crystallization. The IC with PO having higher TC as guest molecules showed higher nucleation effect than the IC with PO having lower TC as guest molecules. The results suggest that the nucleation effect of these ICs was affected by the kinds of the guest molecules. The higher TC guest molecules could result in higher nucleation effect. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献