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41.
42.
Jun'ichiro Hara 《Journal of Low Temperature Physics》1981,43(5-6):533-548
The diffusive thermal conductivity (t) of superfluid 3He-B is calculated in the s-p-d-wave approximation by solving the Boltzmann equation for the Bogoliubov-Valatin quasiparticles variationally. A new set of Landau para- meters calculated from recent heat capacity data as well as old ones given in Wheatley's review are used to estimate the scattering amplitudes of the collision integral. Landau parameters F
2
s, F
1
a, and F
2
a are treated as free parameters under the constraint that exact(T
c) = exp(T
c), where exact and exp are the exact theoretical value and the experimental value, respectively. We have varied F
2
s, F
1
a, and F
2
a over a wide range % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaai4Eaiabgk% HiTiaaigdacaaIWaGaeyizImQaaeyqamaaDaaaleaacaqGXaaabaGa% ae4CaiaabYcacaqGHbaaaOGaeyyyIORaaeOramaaDaaaleaacaqGXa% aabaGaae4CaiaabYcacaqGHbaaaOGaai4laiaacUfacaaIXaGaey4k% aSIaaeOramaaDaaaleaacaqGXaaabaGaae4CaiaabYcacaqGHbaaaO% Gaai4laiaacIcacaaIYaGaamiBaiabgUcaRiaaigdacaGGPaGaaiyx% aiabgsMiJkaaigdacaaIWaGaaiyFaaaa!570F!\[\{ - 10 \leqslant {\text{A}}_{\text{1}}^{{\text{s,a}}} \equiv {\text{F}}_{\text{1}}^{{\text{s,a}}} /[1 + {\text{F}}_{\text{1}}^{{\text{s,a}}} /(2l + 1)] \leqslant 10\} \] and found the possible range of the reduced diffusive thermal conductivity % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGafqOUdSMbaG% aacaGGOaGaaeivaiaabMcacaqG9aGaeqOUdSMaaeikaiaabsfacaqG% PaGaaeivaiaab+cacqaH6oWAcaGGOaGaaeivamaaBaaaleaacaqGJb% aabeaakiaacMcacaqGubWaaSbaaSqaaiaabogaaeqaaaaa!46ED!\[\tilde \kappa ({\text{T) = }}\kappa {\text{(T)T/}}\kappa ({\text{T}}_{\text{c}} ){\text{T}}_{\text{c}} \]. The behavior of \~(T) in the s-p-d-wave approximation does not much depend on the values of the Landau parameters, and \~(t) decreases monotonically with decreasing tem- perature. 相似文献
43.
Weidong Ding Ryota Hayashi Kohei Ochi Junya Suehiro Kiminobu Imasaka Masanori Hara Noriaki Sano Eiichi Nagao Tadao Minagawa 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(6):1200-1207
Chemical byproducts analysis has been recognized as a powerful diagnosis method for SF6 gas-insulated switchgear (GIS). The authors have previously demonstrated that a carbon nanotube (CNT) gas sensor could detect partial discharge (PD) generated in SF6 gas. However, PD-generated decomposition gas species, which were responsible for the CNT gas sensor response, have not been identified yet. In this paper, two kinds of experiments were conducted in order to identify the responsible decomposition gas species. At first, the decomposition gas molecules adsorbed on CNTs were analyzed by Fourier transformation infrared (FTIR) spectroscopy. FTIR absorbance was observed around 735 cm-1 after CNTs were exposed to PD generated in SF6. In the second experiment, the CNT gas sensor responses to typical SF6 decomposition products (HF and SF4) were examined. The CNT gas sensor responded to these gases in the same way as to PD generated in SF6. SF4 response was larger than HF response. Based on these results, SF 4 and SOF2 emerged as candidates for the responsible decomposition gases. Electrochemical interactions between adsorbed gas molecules and CNT were discussed based on theoretical predictions of molecular orbital calculations. The calculation results suggested that both of SOF2 and SF4 could increase the CNT gas sensor conductance 相似文献
44.
Atsushi Ikeda Tatsuya Suzuki Masao Aida Yasuhiko Fujii Toshiaki Mitsugashira Mitsuo Hara Masaki Ozawa 《Progress in Nuclear Energy》2005,47(1-4):454-461
A novel chromatographic separation technique using a tertiary pyridine type resin has been applied to the partitioning of the trivalent actinides (An) and lanthanides (Ln) and several successful results have been shown. In an alcoholic hydrochloric acid system, the trivalent An were clearly separated from the Ln, while no such group separation was achieved in an alcoholic nitric acid system. On the other hand, the nitric acid system was more effective for the intragroup (i.e. individual) separation of the trivalent An and the Ln than the hydrochloric acid system. On the basis of these results, a novel concept for the partitioning of the trivalent An and Ln using the present separation technique and its flowchart have been proposed with its advantages and disadvantages. 相似文献
45.
46.
This paper studies optimal tracking and regulation control problems, in which objective functions of tracking error and regulated response, defined by integral square measures, are to be minimized jointly with the control effort, where the latter is measured by the plant input energy. Our primary objective in this work is to search for fundamental design limitations beyond those known to be imposed by nonminimum phase zeros, unstable poles, and time delays. For this purpose, we solve the problems explicitly by deriving analytical expressions for the best achievable performance. It is found that this performance limit depends not only on the plant nonminimum phase zeros, time delays, and unstable poles-a fact known previously-but also on the plant gain in the entire frequency range. The results thus reveal and quantify another source of fundamental performance limitations beyond those already known, which are nonexistent when only conventional performance objectives such as tracking and regulation are addressed without taking into account the control energy constraint. Among other things, they exhibit how the lightly damped poles, the anti-resonant zeros, as well as the bandwidth of the plant may affect the performance. 相似文献
47.
Toshikazu Fujino Katsumi Iwamoto Kentaro Tanaka Masayuki Shima 《Tribology International》2007,40(10-12):1638
In recent years, the techniques improving sliding performances have progressed by using coated films possessing superior tribological properties, to reduce the failures of the mechanical elements. Those techniques are often used under severe conditions such as elastohydrodynamic lubrication (EHL). In this paper, numerical three-dimensional analysis of the maximum shear stress applied into the coated film and substrate under a single EHL operating condition was performed with a range of coated film thickness and elastic properties. The strength of coated film as one of those techniques was evaluated numerically, resulting in an optimum design of coated film. As a result, coated films with a larger value of thickness and a smaller modulus of elasticity than that of substrate are preferable. 相似文献
48.
M Hara YM Liu L Zhen IS Cohen H Yu P Danilo K Ogino JP Bilezikian MR Rosen 《Canadian Metallurgical Quarterly》1997,96(10):3704-3709
BACKGROUND: The classic calciotropic hormone parathyroid hormone (PTH) and its paracrine factor parathyroid hormone-related protein (PTHrP) both increase heart rate. METHODS AND RESULTS: We used standard electrophysiological techniques to study the effects of PTH and PTHrP on isolated rabbit sinus node, isolated canine Purkinje fibers, and disaggregated rabbit sinus node myocytes. Sinus node maximum diastolic potential, activation voltage, and amplitude were unchanged by PTH or PTHrP (P>.05). However, the slope of phase 4 and the automatic rate were increased at PTH and PTHrP > or = 10 nmol/L (P<.05). Comparable results were seen in canine Purkinje fibers. We then used the perforated-patch technique to study the I(f) pacemaker current in sinus node. PTH 12.5 nmol/L and PTHrP 12.5 to 18 nmol/L increased I(f) at -65 mV by 68+/-41% (n=5) and 69+/-50% (n=5), respectively. Actions of both agents were reversible. The increase in I(f) appeared to result from a change in maximal conductance and not a shift in the voltage dependence of activation. CONCLUSIONS: These observations provide, for the first time, direct electrophysiological support for the chronotropic actions of PTH and PTHrP. They suggest that classic hormones and paracrine factors can have multiple functions and that in the case of PTH and PTHrP, a newly recognized action is to alter automaticity directly. 相似文献
49.
Yoshihisa Ohashi Kentaro Uchida Kensuke Fukushima Masashi Satoh Tomohisa Koyama Maho Tsuchiya Hiroki Saito Katsufumi Uchiyama Naonobu Takahira Gen Inoue Masashi Takaso 《International journal of molecular sciences》2022,23(21)
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary. 相似文献
50.
Incremental Focus of Attention for Robust Vision-Based Tracking 总被引:3,自引:0,他引:3
We present the Incremental Focus of Attention (IFA) architecture for robust, adaptive, real-time motion tracking. IFA systems combine several visual search and vision-based tracking algorithms into a layered hierarchy. The architecture controls the transitions between layers and executes algorithms appropriate to the visual environment at hand: When conditions are good, tracking is accurate and precise; as conditions deteriorate, more robust, yet less accurate algorithms take over; when tracking is lost altogether, layers cooperate to perform a rapid search for the target and continue tracking.Implemented IFA systems are extremely robust to most common types of temporary visual disturbances. They resist minor visual perturbances and recover quickly after full occlusions, illumination changes, major distractions, and target disappearances. Analysis of the algorithm's recovery times are supported by simulation results and experiments on real data. In particular, examples show that recovery times after lost tracking depend primarily on the number of objects visually similar to the target in the field of view. 相似文献