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81.
Haruyuki Murakami Hiroshi Ueda Atsushi Ishiyama Norikiyo Koizumi Kiyoshi Okuno 《Electrical Engineering in Japan》2010,171(3):7-15
In the ITER Engineering Design Activity (EDA), four NB3Sn model coils were developed and successfully tested. However, it was revealed that the critical current of the conductor degraded with the increase of electromagnetic force. One of the explanations of this phenomenon is a strand bending caused by enormous electromagnetic force. The authors therefore developed a simulation code using the distributed circuit model to investigate dependency of the critical current performance on the periodic bending deformation. The simulation results were in good agreement with the experiments. The dependence of the critical current on the periodic transverse load, temperature, periodic load pitch, thickness of Ta barrier which prevents Cu stabilizer from being contaminated by Sn, twist pitch of the strand, and RRR of the bronze matrix was investigated using the developed code. The results showed that the critical current degraded less with decreasing the pitch of the transverse load and increasing the Ta barrier thickness. It suggests that the shorter cabling pitch and the larger bending stiffness prevent the critical current degradation. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(3): 7–15, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20923 相似文献
82.
83.
Walber Arantes da Silva Juliana Aparecida Aricetti Alice Eiko Murakami Jesuí Vergílio Visentainer Makoto Matsushita 《LWT》2009,42(2):660-73
This experiment was carried out with 58-week old laying quails (Coturnix coturnix japonica) assigned to four treatment groups with eight quails per replication in six repetitions in a completely randomized design. The treatments consisted of diets with different levels of flaxseed (0, 1.5, 3.0, and 5.0%). The amounts of cholesterol and total lipids and the fatty acid composition of quail egg yolk were determined in four 21-day cycles. No difference was found in cholesterol levels between the four treatments and the four cycles. The increased ingestion of linolenic acid (LNA) in diet reduced the formation of arachidonic acid (AA) significantly. The 3.0 and 5.0% treatment groups presented a reduction in total saturated fatty acids (TSFA) with the increase in percent flaxseed in feed comparatively to the control value. The n-3 fatty acid level was high in all treatments when compared to that of the control group. The n-6/n-3 ratio decreased from 21.30 (control) to 4.52 (5.0%), which is a better value from the nutritional viewpoint. 相似文献
84.
Some approximate indexing schemes have been recently proposed in metric spaces which sort the objects in the database according to pseudo-scores. It is known that (1) some of them provide a very good trade-off between response time and accuracy, and (2) probability-based pseudo-scores can provide an optimal trade-off in range queries if the probabilities are correctly estimated. Based on these facts, we propose a probabilistic enhancement scheme which can be applied to any pseudo-score based scheme. Our scheme computes probability-based pseudo-scores using pseudo-scores obtained from a pseudo-score based scheme. In order to estimate the probability-based pseudo-scores, we use the object-specific parameters in logistic regression and learn the parameters using MAP (Maximum a Posteriori) estimation and the empirical Bayes method. We also propose a technique which speeds up learning the parameters using pseudo-scores. We applied our scheme to the two state-of-the-art schemes: the standard pivot-based scheme and the permutation-based scheme, and evaluated them using various kinds of datasets from the Metric Space Library. The results showed that our scheme outperformed the conventional schemes, with regard to both the number of distance computations and the CPU time, in all the datasets. 相似文献
85.
H. Murakami M. Tonouchi T. Uchiyama I. Iguchi Z. Wang 《Journal of Superconductivity》2002,15(5):345-350
A phase-sensitive time-domain terahertz-transmission spectroscopy was carried out on a c-axis oriented underdoped Bi2Sr2CaCu2O8 + thin film. We directly extracted the complex refractive index and conductivity at frequencies from 0.3 to 1.5 THz by numerically solving the observed complex transmittance without Kramers–Kronig analysis. The frequency-resolved real and imaginary part of the conductivity (1.0 THz < f) showed a measurable increase below the characteristic temperature of T* 210 K because of the appearance of partial phase-coherence with an ultrashort lifetime less than about 1 ps. 相似文献
86.
Kim YJ Yoshizawa M Takenaka S Murakami S Aoki K 《Journal of Bioscience and Bioengineering》2002,93(6):584-588
The two ammonia-assimilating enzymes glutamate dehydrogenase (GDH; EC 1.4.1.4) and glutamine synthetase (GS; EC 6.3.1.2) were synthesized steadily during the cell growth of Klebsiella pneumoniae F-5-2 that can utilize NH4+ and NO3- simultaneously under aerobic conditions. The enzymes were purified to homogeneity from cell extracts and characterized. The molecular mass of the purified GDH was 300 kDa with six identical 52-kDa subunits. GDH showed its maximal activity (aminating) at pH 8.0 and was stable between pHs 5.5 and 11.5. The enzyme was NADP-specific and strongly inhibited by Ag+. It catalyzed the amination of 2-ketovalerate, 2-ketoadipate, and 2-ketobutyrate, in addition to 2-ketoglutarate. The purified GS has a molecular mass of 470 kDa with eight identical 60-kDa subunits. GS showed its maximal activity at pH 8.0 and was stable between pHs 6.0 and 7.0. The enzyme was strongly inhibited by Fe3+, Hg2+, and Cu2+. 相似文献
87.
Numerical prediction of fraction of eutectic phase in Sn−Ag−Cu soldring using the phase-field method
Machiko Ode Minoru Ueshima Taichi Abe Hideyuki Murakami Hidehiro Onodera 《Journal of Electronic Materials》2006,35(11):1969-1974
A combination of macroscale solidification simulation and phase-field calculation is employed to predict the volume fraction
of the eutectic phase in Sn-4.0 mass% Ag-XCu solder alloys (X=0.5–1.1 mass%). The solidification simulation incorporates the
cooling rate in the phase-field simulation. We assume the residual liquid solidifies as eutectic phase when the driving force
for the nucleation of Cu6Sn5 amounts to a critical value, which is determined based on the experimental data. Though the calculation results depend on
the experimental data, the obtained fractions are about 40% for 0.5 mass% Cu and more than 90% for 1.1 mass% Cu alloy, which
shows good agreement with the experimental data. 相似文献
88.
H Sentsui R Takami T Nishimori K Murakami T Yokoyama Y Yokomizo 《Canadian Metallurgical Quarterly》1998,60(12):1329-1333
PURPOSE: Lamotrigine (LTG) is recognised as effective add-on therapy for focal epilepsies, but this is the first double-blind, placebo-controlled, crossover study in treatment-resistant generalised epilepsy. METHODS: The study consisted of 2 x 8-week treatment periods followed by a 4-week washout period. Patients received doses of either 75 or 150 mg daily, depending on their concomitant antiepileptic drugs (AEDs). Long-term continuation was offered at the end of the study with open-label LTG. RESULTS: Five centres in Australia recruited 26 patients who were having absence, myoclonic, or generalized tonic-clonic seizures or a combination of these. Twenty-two patients completed the study. There was a significant reduction in frequency of both tonic-clonic and absence seizure types with LTG. A 350% decrease in seizures was observed for tonic-clonic seizures in 50% of cases and for absence seizures in 33% of evaluable cases. Rash was the only adverse effect causing discontinuation. Twenty-three of 26 opted for open-label LTG, with 20 still receiving LTG for a mean of 26 months. In these 20, 80% had > or =50% seizure reduction and five (25%) were seizure free. CONCLUSIONS: This study shows that LTG is effective add-on therapy in patients with refractory generalised epilepsies. Statistically significant reduction in seizures in both absence and tonic-clonic seizure types was seen even with low doses of LTG. 相似文献
89.
90.
I Kitagawa K Hori T Motozawa T Murakami M Yoshikawa 《Canadian Metallurgical Quarterly》1998,46(12):1901-1906
Friedreich's ataxia is the first known autosomal recessive disease caused by an unstable trinucleotide expansion mutation. The most frequent mutation is expansion of a GAA repeat in the first intron of gene X25. We studied transmission of the expanded GAA repeat in 37 Friedreich's ataxia pedigrees and analysed blood and sperm alleles in eight patients. We showed intergenerational instability in 84% of the alleles with an overall excess of contractions. Both contractions and expansions of the GAA repeat occurred in maternal transmission with a stronger tendency to expand for smaller repeats and to contract for longer repeats. Paternally transmitted alleles contracted only. Parental age and the intergenerational change in expansion size were directly correlated in maternal transmission and inversely in paternal transmission. The size of the GAA expansion was slightly lower in patients than heterozygous carriers. Sperm analysis confirmed the tendency to contract of paternal alleles, which was more marked with ageing. The degree of contraction of the GAA repeat in sperm was much higher than that found in intergenerational transmission and was directly related to the repeat size. A blood expanded allele reverted to normal size in the sperm of one patient. This study suggests the existence of different mutational mechanisms in Friedreich's ataxia alleles, which occur both pre- and post-zygotically. 相似文献