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排序方式: 共有644条查询结果,搜索用时 15 毫秒
71.
Kan Okubo Masakazu Takayama Nobunao Takeuchi 《Electromagnetic Compatibility, IEEE Transactions on》2007,49(1):163-169
To clarify the relationship between earthquakes and electrical phenomena, signals of three parameters were observed continuously at Sennan in Akita Prefecture, Japan: ground acceleration (GAC), earth potential difference (EPD), and electrostatic field in the atmosphere (EFA). A large metal plate was used as an electrostatic antenna to observe EFA variation. For this paper, we used the digital natural observation (D-NOB) method as a signal processing technique and found clear EPD and EFA waveforms during seismic wave propagation. Our observation and examination results show that GAC causes EPD variation. Subsequently, the EPD variation induces EFA variation 相似文献
72.
Annealing effects of a high-quality ZnTe substrate 总被引:1,自引:0,他引:1
Kenji Yoshino Minoru Yoneta Kenzo Ohmori Hiroshi Saito Masakazu Ohishi Takayuki Yabe 《Journal of Electronic Materials》2004,33(6):579-582
The sharp photoluminescence (PL) and optical-reflection spectra in the bandedge region of the high-quality nondoped ZnTe substrate
(100) were observed at 4.2 K. Free exciton, associated with lower and upper polaritons (EXL and EXU) at 2.382 eV and 2.381 eV, respectively, were clearly observed. This meant that this substrate was high quality. The intensity
of a bound exciton peak (2.375 eV), which is caused by a Zn vacancy, of a neutral acceptor decreased with an increase of the
Zn vapor pressures. 相似文献
73.
Masakazu Ichiyanagi 《Open Systems & Information Dynamics》1998,5(3):249-264
A critical discussion is given of the idea that the relation between microscopic dynamics and thermodynamics can be based on the concept of relative entropy. It is shown how dissipation can be treated in the response theory under certain conditions. A thermodynamic interpretation of the dynamical semigroup theory for a system interacting with its surroundings is given. By utilizing the method of maximum entropy with the well specified set of relevant observables, the construction of thermodynamic entropy is demonstrated. It is argued that the statistical (say, information) entropy cannot be identified with the thermodynamic entropy and that the relation between the two entropies is written in terms of the relative entropy. In this form, the distinction between the H-theorem and the second law of thermodynamics is easily made. It should be kept in mind that the H-theorem is for the kinetic stage while the second law is for the thermodynamic (or, hydrodynamic) stage. 相似文献
74.
Masakazu Goto Alex H Gordon Andrew Chesson 《Journal of the science of food and agriculture》1991,56(2):141-153
Straw samples from five cultivars of spring barley (Hordeum vulgare L; Golden Promise, Golf, Klaxon, Heriot and Doublet), selected to show a range of rumen degradabilities, were examined to measure the effect of gaseous ammonia on aspects of their cell wall composition and degradability after treatment. Cellulose degradability of the untreated straws, as measured by the nylon-bag method, ranged from 41.0% for Golden Promise to 57.1% for Doublet. The extent of improvement in degradability following ammonia treatment was 12.5% units for Golden Promise and only 2.5% units for Doublet, showing that the effect of ammonia was more pronounced for materials of lower inherent degradability (r= ?0.774). Straw from three of the five cultivars was dissected into its botanical parts, and the dry matter content and digestibility of the fractions were determined. Leaf material formed a higher fraction of dry matter in Doublet (0.48), the most degradable cultivar, than in Golden Promise (0.30), the least degradable straw. Half of the observed difference in degradability between Doublet and Golden Promise could be attributed to differences in dry matter distribution between botanical fractions. For untreated straw, degradability was weakly, negatively correlated with the proportion of arabinose residues substituted with alkali-labile linkages at position 0–5 (r = ?0.690), and positively correlated with the moisture retention (water-holding capacity) of straws (r = 0.838), water-soluble dry matter content (r = 0.922) and water-soluble phenolic content (r = 0.791). The proportion of pentose residues carrying alkali-labile linkages was only slightly decreased followign ammonia treatment. In the case of the 0–5 position of arabinose residues the original values were reduced by 2.4–15.9%. Ammonia treatment had little effect on the capacity of the straw to retain moisture, and did not significantly increase the proportion of water-soluble dry matter or phenolics. Cellulose degradability, or the improvement in degradability, of ammonia-treated straw was not correlated with any of the physical and chemical characteristicds of staw considered above. 相似文献
75.
T Kimura Y Nakaoka K Yoshida T Sunami Y Murahashi H Hisatsune N Kuriyama S Sekikawa N Kurihara 《Canadian Metallurgical Quarterly》1998,37(7):646-650
BACKGROUND: High immigration rates contribute to the high incidence of pediatric tuberculosis (TB) in San Diego, Calif. Adolescents frequently have poor access to health care and may not receive appropriate TB screening. School-based screening has been ineffective in detecting TB in other parts of the country. OBJECTIVE: To determine the prevalence of TB infection and disease in a high-risk population of high school students through school-based screening. DESIGN AND PARTICIPANTS: Cross-sectional study of TB prevalence and an analysis of risk factors for TB infection in students attending 2 San Diego high schools with high percentages of non-US-born students. MAIN OUTCOME MEASURES: Positive induration (> or =10 mm) with Mantoux tuberculin skin test. A chest radiograph or clinical findings consistent with active TB. RESULTS: A total of 744 (36%) students at high school 1 and 860 (57%) students at high school 2 participated. Ninety-five (12.8%) and 207 (24.1%) students, respectively, had positive tuberculin skin test results. One student had a chest radiograph that showed active TB. Smear for acid-fast bacteria and culture for Mycobacterium tuberculosis had negative results. Vietnamese, Filipino, and Latino ethnic groups were significantly more likely to have positive tuberculin skin test results than the white population (P<.05). Non-US-born students were significantly more likely to have positive tuberculin skin test results than US-born students in all ethnic groups except the Latino group. CONCLUSION: Although treatment of TB coupled with aggressive public health investigation is the most cost-beneficial way of preventing TB, targeted school-based screening may be an effective way of detecting TB infection in high-risk populations with poor access to health care. 相似文献
76.
Toshihide Igari Shoji Kitade Masahiro Ueta Masakazu Ichimiya Kimitaka Kimura Yoshimi Satoh Koji Take 《Nuclear Engineering and Design》1993,140(3):341-348
A new prediction method for the thermal ratchetting of a cylinder subjected to an axially moving temperature distribution is proposed in this paper. This ratchetting is quite different from the conventional Bree-type ratchetting, and an advanced evaluation method has been required in the structural design of FBR components. The proposed method considers the work hardening of actual materials for FBR components. Firstly the basic scheme of the prediction method is shown, and secondly the application procedure to the actual design is shown. Predicted results by using this method coincide well with experimental results, when compared with the case by using the previous method. 相似文献
77.
Yoshio Hayakawa Masakazu Nishida Hiroshi Kimoto Shozo Fujii Hideo Sawada 《Polymer Bulletin》1994,32(5-6):661-668
Summary Three polymers bearing benzene rings: polystyrene, poly(2,6-dimethyl-p-phenylene oxide) and poly(diphenylacetylene), were chemically modified with bis(heptafluorobutyryl) peroxide. The heptafluoropropylated products have higher gas permeabilities than the parent polymers. In the pervaporation of aqueous ethanol, modified poly(diphenylacetylene) showed ethanol permselectivity. 相似文献
78.
The effects of the onset of lasing on the I-V characteristics, the impedance characteristics and the light modulation characteristics of laser diodes have been discussed by introducing the rate equations which involve carrier diffusion process in the active layer interacting with the radiation field intensity. The static I-V characteristics exhibit a kink at lasing threshold current, reflecting the decrease of effective lifetime of carriers. Effective carrier lifetimes decrease with increasing light intensity, which results in a steep attenuation of injected carrier density in the active region. The impedance and light modulation characteristics are obtained in the small signal approximation. The small signal light modulation characteristics depend strongly on whether the laser diode is excited by the constant current modulation or the constant voltage modulation. The impedance is changed drastically by the onset of lasing and exhibits a resonance which coincides exactly with the optical modulation resonance frequency. 相似文献
79.
Kunihiro Hamaba Naoto Yokoyama Masakazu Kato Yoshiki Takabayashi 《Electrical Engineering in Japan》1992,112(2):101-109
A technique of calculating the frequency bias of an electric power system from frequency fluctuation data and total output power is described. An evaluation method for testing the calculations by the new method is developed. The results are in good agreement with estimates based on generator speed regulation but the method gives an excessively high figure for the load frequency bias. 相似文献
80.
Shimazu Hideaki Yamakoshi Ken-Ichi Togawa Tatsuo Fukuoka Masakazu Ito Hiroshi 《IEEE transactions on bio-medical engineering》1982,(1):1-7
We devised a compensation technique that measures the admittance change of a limb submerged in an electrolyte solution in a cylinder. Using this technique, we evaluated the accuracy of admittance plethysmography and the validity of the parallel-conductor model on which the theory of blood flow measurement by electrical admittance (or impedance) plethysmography is based. From a theoretical point of view, if a limb is regarded as a parallel-conductor model, the admittance change due to blood pooling following venous occlusion should disappear when the resistivity of the solution is equal to that of the blood. 相似文献