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排序方式: 共有901条查询结果,搜索用时 15 毫秒
101.
This paper presents a new algorithm to find an appropriate similarityunder which we apply legal rules analogically. Since there may exist a lotof similarities between the premises of rule and a case in inquiry, we haveto select an appropriate similarity that is relevant to both thelegal rule and a top goal of our legal reasoning. For this purpose, a newcriterion to distinguish the appropriate similarities from the others isproposed and tested. The criterion is based on Goal-DependentAbstraction
(GDA) to select a similarity such that an abstraction basedon the similarity never loses the necessary information to prove the ground (purpose of legislation) of the legal rule. In order to cope withour huge space of similarities, our GDA algorithm uses some constraintsto prune useless similarities. 相似文献
102.
103.
Constructing communication protocols from component service specifications, each of which specifies a subfunction of the target protocol, enables efficient development of a large and complex communication protocol. Concerning this construction, related techniques have been already proposed: integration of component protocol specifications into a single protocol specification and transformation of service specifications to protocol specifications. However, the integration needs special knowledge of communication protocols, and the transformation requires that a large and complex service specification should be developed as input to produce the target protocol. In order to cope with these problems, this paper proposes a new method which at first integrates component service specifications into a single service specification, and then transforms the service specification into the target protocol by a protocol synthesis technique. The most important point of view is that component integration is performed at the service specification level rather than the protocol specification level. Additionally, we define a class of ‘well-formed’ service specification which ensures correctness of the target protocol. As a result, the integration and transformation can be efficiently executed in small state space without special knowledge of communication protocols. Finally, we have shown the effectiveness of the proposed method by constructing a part of the real-life OSI protocol FTAM. 相似文献
104.
Toshio Shimoo Yoshiaki Morisada Kiyohito Okamura 《Journal of the American Ceramic Society》2003,86(5):838-845
Three types of polycarbosilane-derived SiC fibers (Nicalon, Hi-Nicalon, and Hi-Nicalon S) with different SiO2 film thicknesses ( b ) were subjected to exposure tests at 1773 K in an argon-oxygen gas mixture with an oxygen partial pressure of 1 Pa. The suppression effect of a SiO2 coating on active oxidation was examined through TG, XRD analysis, SEM observation, and tensile tests. All the as-received fibers were oxidized in the active-oxidation regime. The mass gain and the SiO2 film development showed a suppression of active oxidation at b values of ≧0.070 μm for Nicalon, ≧0.013 μm for Hi-Nicalon, and ≧0.010 μm for Hi-Nicalon S fibers. Considerable strength was retained in the SiO2 -coated fibers. For Hi-Nicalon fibers, the retained strength was 71%–90% of the strength in the as-received state (2.14–2.69 GPa). 相似文献
105.
The photopolymerization of vinyl monomers was studied by the system of metal-amine complex and carbon tetrachloride. Addition of amines to the initiating system generally accelerates the polymerization. The acceleration by various sorts of amines in different solvents was examined. It was confirmed that the photopolymerization in question is of free radical character. The polymerization mechanism was discussed. 相似文献
106.
Diffusion of vanadium,chromium, and manganese in copper 总被引:2,自引:0,他引:2
Kazutomo Hoshino Yoshiaki Iijima Ken-Ichi Hirano 《Metallurgical and Materials Transactions A》1977,8(3):469-472
The diffusion coefficients of vanadium, chromium and manaanese in copper have been determined by the residual activity method
with radioactive tracers V48, Cr51 and Mn54 in the temperature ranges between 955 and 1342 K, between 999 and 1338 K and between 971 and 1253 K, respectively. The temperature
dependence of the diffusion coefficients is expressed by the following Arrhenius equations along with the probable errors:D
V/Cu = (2.48
-0.44
+0.53
) x 10−4 exp [-(215 ± 2) kJ mol−1/RT] m2 per s,D
Cr/Cu = (0.337
-0.090
+0.124
) x 10−4 exp [-(195 ± 3) kJ mol−1/RT] m2 per s,D
Mn/Cu = (1.02
-0.18
+0.22
) x 10−4 exp [-(200 ± 2) kJ mol−1/RT] m2 per s.
Anomalous penetration profiles for the diffusion of Cr51 and Mn54 in the present results suggest that experimental results onD
Cr/Cu andD
Mn/Cu in the past have been influenced by oxidation and evaporation of the chemically active radiotracers during annealing for
diffusion.
formerly Graduate Student, Tohoku University 相似文献
107.
108.
This paper concerns the RNG based algebraic turbulence model. This model has characteristics to capture transitional process from laminar to turbulent flow. This is determined by the argument of the Heaviside function, which becomes a threshold for the occurrence of turbulence. It is supposed that proper modeling of this argument will lead to correctly capture transition location. In the present paper, this argument is modeled in such a way that the form of cubic equation for the turbulent kinematic viscosity be maintained. Moreover, the length scale which is required to calculate the turbulent kinematic viscosity is newly proposed, taking into account the freestream pressure gradient. The validation is performed by comparing the calculated results with the empirical expressions as well as the experimental data. This model can simulate the streamwise intermittency effect, by which a sudden increase of skin friction is prevented. Moreover, the transition location can be predicted within reasonable accuracy compared with the experimental data. 相似文献
109.
The permeation characteristics for polymer aqueous solution and asymmetric structure of cellulose nitrate membranes, in particular the finger-like cavity in the back sponge layer of these membranes, were investigated by changing the preparation conditions of the membranes— the casting solvent, evaporation period, and gelation medium. The formation of the finger-like cavity was dependent on absorption of a water molecule into the casting mixture from the atmosphere during the solvent evaporation process and the exchange velocity between the casting solvent and the gelation medium. The mechanism and conditions for the formation of a finger-like cavity in cellulose nitrate membranes were discussed. 相似文献
110.
Y. Akiniwa K. Tanaka N. Taniguchi 《Fatigue & Fracture of Engineering Materials & Structures》1988,11(5):343-354
Abstract— Single-edge-notched specimens of a low-carbon steel were fatigued under cyclic in-plane bending with compressive mean stresses. The development of crack closure with crack growth was studied both experimentally and theoretically. The relation between the crack opening stress and the crack length was a function of the minimum (compressive) applied stress, irrespective of the maximum stress. The effective stress intensity range was a unique parameter in correlating the crack growth rate, even if the crack was embedded in the compressive plastic zone. Under a constant minimum stress, the length of nonpropagating cracks became longer with increasing maximum applied stress. A theoretical model was proposed for predicting the crack opening stress on the basis of the compressive stress distribution at the minimum applied stress. The predicted value agreed fairly well with the experimental result. The model gave upper bounds of the crack growth rate and the length of nonpropagating fatigue cracks within the plastic zone. 相似文献