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51.
Yoshimasa A. Ono Jun'ichiro Hara Katsuhiko Nagai Kiyoshi Kawamura 《Journal of Low Temperature Physics》1977,27(3-4):513-536
The shear viscosity (T) in the Balian-Werthamer (BW) state of superfluid
3
He is calculated variationally throughout the region 0t 1(t=T/T
c) from the transport equation for Bogoliubov quasiparticles. Coherence factors are treated exactly in the calculation of the collision integral. The numerical result for
=s= s(T)/n(Tc) agree very well with experiment in the range 0.8t1.0. Analytic expressions
= 0.577 (1–1.0008t) and
=1–(23/64) [=(T)/k
B
T] are obtained in the low-temperature region and in the vicinity ofT
c, respectively. From the numerical analysis it is shown that the latter equation is valid only in the temperature range 0.9997t1.0.Supported by the Research Institute for Fundamental Physics, Kyoto University. 相似文献
52.
Suganuma T. Imai S. Kinoshita T. Sugawara K. Shiratori N. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2003,33(5):633-641
We present a design and implementation of a flexible videoconference system (VCS) using multiagent computing technology. The proposed system, we named FVCS, aims to reduce the burden of the users under the operational environment with insufficient computational resources, such as the Internet environment with small-scale computers at homes and offices, by embedding flexibility to the conventional videoconference system. In this paper, we design and implement FVCS with knowledge-based multiagent framework to realize adaptability of FVCS. We also evaluate the adaptability of the prototype systems of FVCS based on an operational situation observed in its experiments. From the result of the experiments, we conclude that the multiagent-based design and implementation is reasonable for construction of FVCS. 相似文献
53.
54.
Coudert made a breakthrough in the two-level logic minimization problem with Ordered Binary Decision Diagrams (OBDDs for
short) recently [3]. This paper discusses the relationship between the two OBDDs of a monotone function and its prime implicant
set to clarify the complexity of this practically efficient method. We show that there exists a monotone function which has
an O(n) size sum-of-products but cannot be represented by a polynomial size OBDD. In other words, we cannot obtain the OBDD of the
prime implicant set of a monotone function in an output-size sensitive manner once we have constructed the OBDD of that function as in [3], in the worst case. A positive result is also given for a meaningful
class of matroid functions.
Received April 1997, and in revised form December 1997, and in final form February 1998. 相似文献
55.
Kenji Imai Koji Takai Tatsunori Hanai Makoto Shiraki Yusuke Suzuki Hideki Hayashi Takafumi Naiki Youichi Nishigaki Eiichi Tomita Masahito Shimizu Hisataka Moriwaki 《International journal of molecular sciences》2014,15(7):11294-11306
Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis. 相似文献
56.
Satoshi Nogami Katsuhiko Minoura Nao Kiminami Yui Kitaura Hiromasa Uchiyama Kazunori Kadota Yuichi Tozuka 《Advanced Powder Technology》2021,32(5):1750-1756
Although curcumin is considered to have various therapeutic effects, its use as a functional food or supplement is restricted owing to its low water solubility and bioavailability. To increase the solubility of curcumin in water, the use of polyvinylpyrrolidone (PVP) and vinylpyrrolidone-vinyl acetate copolymers with a pyrrolidone skeleton was noted to be promising. In particular, the bi-component formulations of curcumin/PVP prepared through spray drying exhibited an amorphous state in powder X-ray diffraction observations and temporally increased the apparent solubility of curcumin to over 5000 times that of untreated curcumin; nevertheless, after 24 h, the solubility decreased owing to the unstable supersaturated state of curcumin. The addition of α-cyclodextrin (α-CyD) in the bi-component curcumin/PVP formulation helped maintain the supersaturated state of curcumin, whereas the addition of β- and γ-CyD led to the collapse of the supersaturated state. The addition of α-CyD can likely help inhibit the nucleation and crystal growth of curcumin, through the interaction among the solubilized units of curcumin/PVP and α-CyD. 相似文献
57.
Optimal Digital Controller Design for a Servo Motor Taking Account of Intersample Behavior 下载免费PDF全文
A continuous‐time plant with a discretized continuous‐time controller does not yield stability if the sampling rate is lower than some certain level. Thus far, high‐performance electronic control has made use of expensive hardware needed to implement discretized continuous‐time controllers; low‐cost hardware generally does not have a sufficiently high sampling rate. This technical note presents results comparing performance indexes with and without intersample behavior, and provides some answers to the question of how a low‐specification device can control a plant effectively. We consider a machine simulating wafer handling robots, which is an electromechanical system driven by a direct drive motor, at a semiconductor factory. We illustrate the controller design for the robot with and without intersample behavior, and present simulations and experimental results using these controllers. Taking intersample behavior into account proves to be effective in improving control performance and makes it possible to choose a relatively long sampling period. Controller design in terms of the performance index with intersample behavior makes it possible to deal with situations in which a sufficiently short sampling period may not be employed, and freedom of controller design may be widened, especially regarding the choice of the sampling period. 相似文献
58.
59.
Takuji Kobayashi Katsuhiko Sasaki 《Journal of Materials Science: Materials in Electronics》2009,20(4):343-353
This paper discusses uniaxial ratchetting deformation of lead-free solder alloy Sn–3Ag–0.5Cu and lead-containing solder alloy
Sn–37Pb, which were subjected to tension–compression loading with several stress amplitudes and stress ratios, minimum stress
over maximum stress. First the uniaxial ratchetting tests were conducted with three maximum stresses and four stress ratios.
All tests were conducted using cylindrical bulk specimens of the solder alloys at 313 K. The test results show that there
are differences in the ratchetting deformation behavior of the two solder alloys; the larger ratchetting strain occurs in
the lead-containing solder alloy than in the lead-free solder alloy. The ratchetting deformation was simulated by the dislocation
based constitutive model proposed by Estrin et al. (J Eng Mater Technol 118:441, 1996). The evolution equation of the back
stress employed in the constitutive model was modified considering a dynamic recovery term. The effect of the modification
of the back stress evolution is discussed by comparing the simulations with the corresponding experimental results. The simulations
suggest that the recovery term in the kinematic hardening rule plays an important role in fitting the simulation to the experimental
results of the ratchetting deformation of the solder alloys. 相似文献
60.
Teruhisa Horita Haruo Kishimoto Katsuhiko Yamaji Manuel E. Brito Yueping Xiong Harumi Yokokawa 《Journal of power sources》2009,193(1):180-184
Reactivity of oxide scale on Fe-Cr alloy with Na-containing gases was examined to estimate the stability against sodium (Na): vapors of NaCl and Na2SO4 exposures with air flow at 1073 K. The identified reaction phases were Cr-Mn spinel, Cr2O3, and alloy from the X-ray diffraction of surface with no Na-reaction products. However, the protective oxide scales (Mn-Cr spinel and Cr2O3 layers) on the Fe-Cr alloy were partially decomposed by reacting with Na to form Na-compounds inside the oxide scale/alloy interfaces. In some parts, anomalous oxide scales were found around the oxide scale/Fe-Cr alloy interfaces, with forming Na-rich compounds: the compounds were distributed inner parts of oxide scales around oxide scale/alloy interfaces. The stability of oxide scales and degradation were discussed based on the observed distribution of elements. 相似文献