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Feasible Resolution of Angular Displacement Measurement by an Optical Angle Sensor Based on Laser Autocollimation

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Nanomanufacturing and Metrology 2023年第4期6卷 46-59页

作者： hyunsung Lim yuki Shimizu Division of Mechanical and Aerospace Engineering Hokkaido UniversitySapporoJapan

The feasible resolution of angular displacement measurement by an optical angle sensor based on laser autocollimation is *** the sensor sensitivity while maintaining the noise level of the sensor signal as low as possible is necessary to achieve high-resolution angular displacement *** this paper,the contribution of each component,such as a photodiode,a trans-impedance amplifer,and an analog-to-digital converter in the optical angle sensor,to the noise level of the sensor signal is frst estimated on the basis of theoretical *** feasible sensitivity of the optical angle sensor is also estimated in numerical *** sensitivity of a photodiode element at the edge of its photosensitive area is evaluated in experiments to realize the estimation of the angle sensor *** results are applied to the numerical *** infuences of the measurement laser beam diameter,the spot diameter of the focused laser beam on the photosensitive area,and the focal length of the collimator objective of the optical angle sensor are also consid-ered in the numerical ***,a prototype optical setup is *** are performed to demonstrate that a compact optical angle sensor based on laser autocollimation with a collimator objective having a focal length shorter than 100 mm can achieve a resolution beyond 0.001 arc-second with a bandwidth of 1 *** resolution is better than those achieved by commercial autocollimators employing an image sensor or a position-sensitive *** industrial contribution of this paper lies in the detailed breakdown of noise components in the readout signal of an angle sensor in a practical condition and the systematic estimation of its feasible resolution as well as its sensitivity.

关键词： Angle measurement Resolution Laser autocollimation Photodiode Signal noise

Resource assessment of copper deposits in China

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Journal of Central South University of Technology 2005年第z1期12卷 108-113页

作者： ZhANG Qin-li GU De-sheng T. shoji h. Kaneda School of Resources and Safety Engineering Central South University Changsha 410083 China School of Resources and Safety Engineering Central South University Changsha 410083 China Department of Environment System School of Frontier Sciences the University of Tokyo Tokyo 113-8656 Japan Department of Life Area Environmental Science Faculty of Science the Toho University Tiba 274-8510 Japan

Copper-bearing deposits of China are statistically analyzed in terms of ore grade, metal amount and ore tonnage. Each of grade and metal amount shows more or less a lognormal distribution. Analysis gives 10 copper metallogenic districts, each having specific densities of deposit numbers and copper reserves larger than 3. Based on the ratio of copper in ore value (Rcu), Chinese copper deposits are classified into two groups: mainly copper-producing deposits (MC: Rcu≥0.5) and accessorily copper-producing deposits (AC: Rcu＜0. 5). The grade-tonnage relation of MC deposits can be combined by two exponential functions approximating high grade (＞ 3.0 %) and low grade (＜2.0%) parts. The critical copper grade, which is obtained from the low grade part of the relation, is 0. 34 %. Chinese copper resources are concluded to become pessimistic, because some mines are working with grades close to this critical value. Taking account of the fact that many copper deposits are actually polymetallic, Cu-equivalent grades, which are converted from ratios of metal prices to the copper price, are also introduced. The critical Cu-equivalent grade of MC deposits (0. 43 % ) also suggests that Chinese copper resources are pessimistic.

关键词： copper resources critical grade assessment

Simultaneous estimation of spacecraft position and asteroid diameter during final approach of hayabusa2 to Ryugu

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Astrodynamics 2020年第2期4卷 163-175页

作者： yuki Takao Yuya Mimasu Yuichi Tsuda Institute of Space and Astronautical Science Japan Aerospace Exploration AgencySagamihara252-5210Japan

This paper presents the optical navigation results of the asteroid explorer hayabusa2 during the final rendezvous approach phase with the asteroid *** orbit determination of hayabusa2 during the cruising phase uses a triangulation-based method that estimates the probe and asteroid orbits using the directions from which they are ***,the asteroid size is available as optical information just prior to *** size information allows us to estimate the relative distance between the probe and the asteroid with high accuracy,that is strongly related to the success or failure of the *** this study,the relative distance and asteroid size in real space are simultaneously estimated in real time by focusing on the rate of change of the asteroid size observed in sequential *** real-time estimation results coincided with those of precise analyses performed after arrival.

关键词： asteroids small bodies optical navigation size estimation orbit determination real time

Physical Properties of Liquid Terbium Measured by Levitation Techniques

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Journal of Rare Earths 2007年第6期25卷 665-669页

作者： Paul-Francois Paradis Takehiko Ishikawa Noriyuki Koike yuki Watanabe Japan Aerospace Exploration Agency Institute of Space and Astronautical Science ISS Science Project Office 2-1-1 Sengen Tsukuba Ibaraki 305-8505 Japan Chiba Institute of Technology Tsudanuma Narashino Chiba Japan Advanced Engineering Service Co. Ltd. Tsukuba Ibaraki 305-0032 Japan

To understand the nature and behavior of rare earth metals in their liquid phases, accurate values of their physical properties are essential. however, to measure their physical properties, the samples should be maintained in liquid phases for prolonged time, and this raises a formidable challenge. This is mainly explained by their high melting temperatures （e.g., 1629 K for Tb）, high vapor pressure, and the risk of melt contamination with a crucible or support. An electrostatic levitation furnace alleviated these difficulties and allowed the determination of density, surface tension, and viscosity of several metals above their melting temperature. here, first, the levitation furnace facility and the noncontact diagnostic procedures were briefly discussed, followed by the explanation of their thermophysical property measurements over wide temperature ranges. The density was obtained using an ultraviolet-based imaging technique that allowed excellent illumination, even at elevated temperatures. Over the 1615 to 1880 K temperature span, the density measurements could be expressed as p（T） =7.84 × 10^3 -0.47 （T - Tm）（kg · m^-3） with Tm = 1629 K, yielding a volume expansion coefficient a（T） = 6.0 × 10^-5 （K^-1）. In addition, the surface tension and the viscosity could be determined by inducing a drop oscillation to a molten sample. Using this technique, the surface tension data could be expressed as σ（T） = 8.93 × 10^2 - 0.10 （T - Tm）（mN· m^-1） and those for viscosity as η（T） =0.583 exp [4.1 × 10^4/（RT）] （MPa·s） over the 1690 to 1980 K temperature range

关键词： levitation liquid noncontact terbium rare earths

Stimulation by nizatidine,a histamine h_2-receptor antagonist,of duodenal hCO_3^-secretion in rats:relation to anti-cholinesterase activity

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World Journal of Gastroenterology 2000年第5期6卷 651-658页

作者： Koji Takeuchi shoji Kawauchi hideo Araki Shigeru Ueki Osamu Furukawa Department of Pharmacology and Experimental Therapeutics Kyoto Pharmaceutical UniversityMisasagiYamashinaKyoto 607-8414Japan CURE Bldg.114Suite 217 West LA VAMC 11301 Wilshire Blvd.Los AngelesCA 90073

AIM To examine whether nizatidine stimulates duodenal hCO_3^- secretion in rats by inhibiting AChE activity. METhODS Under pentobarbital anesthesia,a proximal duodenal loop was perfused with saline,and the hCO_3 secretion was measured at ph 7.0 using a ph-stat method and by adding 10mM ***,neostigmine,carbachol or famotidine was administered *** a single injection. RESULTS Intravenous administration of nizatidine(3-30 mg/kg)dose-dependently increased duodenal hCO_3^- secretion,and the effect at 10mg/kg was equivalent to that obtained by carbachol at 0.01 mg/*** nizatidine action was observed at the same dose range that inhibited acid secretion and enhanced gastric motility,mimicked by *** of neostigmine(0.03 mg/kg),and significantly attenuated by bilateral vagotomy and prior s.c. administration of atropine but not by indomethacin,a cyclooxygenase inhibitor,or N^G-nitro-L-arginine methyl ester,a NO synthase *** hCO_3^- secretory response to acetylcholine(0.001 mg/kg)was significantly potentiated by the concurrent administration of nizatidine(3mg/kg,i.v.).The IC_(50)of nizatidine for AChE of rat erythrocytes was 1.4×10^(-6)M,about 12 times higher than that of *** famotidine(>10^(-3)M, 30mg/kg,i.v.)nor cisapride(> 10^(-3)M, 3mg/kg,i.v.)had any influence on AChE activity or duodenal hCO_3^- *** damage induced by acid perfusion(100 mM hCI for 4 h)in the presence of indomethacin was significantly prevented by nizatidine and neostigmine,at the doses that increased the hCO_3^- secretion. CONCLUSION Nizatidine stimulates duodenal hCO_3^- secretion,in both vagal-dependent and atropine-sensitive manners,and the action is associated with the anti-AChE activity of this agent.

关键词： nizatidine histamine h_2 receptor blockaders duodenal hCO_3^-secretion cholinesterase inhibitors rats

Assessing the supercooling of fresh-cut onions at−5℃ using electrical impedance analysis

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Food Quality and Safety 2020年第2期4卷 55-58页

作者： shoji Koide Ami Yoneyama Takahiro Orikasa Matsuo Uemura Faculty of Agriculture Iwate UniversityMoriokaJapan Iwate Agri-Innovation Center Iwate UniversityMoriokaJapan

We supercooled fresh-cut onion at−5℃ for 12 *** supercooling,the electric impedance properties of the samples were evaluated by electrical impedance spectroscopy over the frequency range of 42 hz−5 *** time-temperature profiles of samples indicated that the freezing point and supercooling point were−2.3℃±0.7℃ and−6.9℃±1.0℃,*** results indicated that 34 of the 36 supercooled samples exhibited a definite circular arc in the Cole-Cole plot,which suggested that the cell membrane remained intact during *** the other two samples which did not exhibit a definite circular arc,the cell membrane had sustained serious damage during ***,there was large difference in drip loss percentage between supercooled samples exhibited a definite circular arc in the Cole-Cole plot and samples not exhibiting a definite circular *** results suggest that fresh-cut onions can be supercooled at−5℃.

关键词： supercooling fresh-cut onion electrical impedance Cole-Cole plot supercooling point

Selective Monoprotection of Symmetrical Diols in a Flow Reactor

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International Journal of Organic Chemistry 2018年第2期8卷 264-271页

作者： hisashi Masui Masaru Takizawa yuki Sakai Yasuhiro Kajiwara Kiyofumi Wanibuchi Mitsuru shoji Takashi Takahashi Department of Pharmaceutical Sciences Yokohama University of Pharmacy Yokohama Japan

Desymmetrization reactions provide a powerful approach for the construction of complex molecules. Various methods have been developed for the selective monoprotection of symmetrical diols;however, their application to large-scale operations is limited. In this study, the monotetrahydropyranylation of symmetrical diols in a flow reactor has been developed, whereby the length of the flow reactor tube and the amount of acid were optimized. A higher selectivity for the monoprotected derivative was observed when the reaction was performed in a flow reactor compared with that observed in a conventional batch experiment. The efficient flow method developed herein can be applied to large-scale synthesis by numbering up the flow reactor without affecting the selectivity and yield. Since monoprotection can be achieved without using a large excess of diol, our developed flow method is effective when expensive diol must be used.

关键词： Desymmetrization Selective Monoprotection Flow Synthesis Diols Tetrahydropyranylation

Risk-taking behavior of bull-headed shrikes that recently colonized islands

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Current Zoology 2021年第2期67卷 177-182页

作者： shoji hAMAO hisahiro TORIKAI Midori YOShIKAWA Yutaka YAMAMOTO Tugeru IJIChI Department of Zoology National Museum of Nature and Science4-1-1 AmakuboTsukubaIbaraki305-0005Japan Amami Ornithologists'Club 12-8 Nazewako-choAmamiKagoshima894-0007Japan Conservation Division Wild Bird Society of Japan3-9-23 Nishi-gotandaShinagawa-kuTokyo141-0031Japan KIKAI Institute for Coral Reef Sciences 1508 ShiomichiKikai-choOshima-gunKagoshima891-6151Japan

Individuals which have invaded urbanized environments are reported to engage in riskier behav-iors,possibly influenced by the scarcity of predators in urbanized ***,we studied the risk-taking behavior of birds which had invaded a new natural environment,rather than an artificial urban environment,using recently established populations of the bull-headed shrike Lanius bu-cephalus,which naturally colonized three subtropical islands in *** compared flight initi-ation distance(FID),the distance at which an individual approached by a human initiates flight,be-tween the islands and the temperate *** was longer for the insular shrikes compared with the mainland shrikes after controlling for other factors,indicating that the individuals which had invaded a new natural environment had a lower propensity for risk-taking.A possible explan-ation for these results is that low risk-taking behavior might be adaptive on the islands due to predation by the black rat Rattus rattus,an unfamiliar predator not found in shrike habitats on the temperate *** studies are needed to examine the nest predation rate,predator species,and nest site selection of these insular shrike populations.

关键词： flight initiation distance island population Lanius bucephalus natural introduction predation

Acquiring non-parametric scattering phase function from a single image

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Computational Visual Media 2018年第4期4卷 323-331页

作者： yuki Minetomo hiroyuki Kubo Takuya Funatomi Mikio Shinya Yasuhiro Mukaigawa Nara Institute of Science and Technology 8916-5 Takayama-choIkomaNara630-0192Japan. Toho University 2-2-1 MiyamaFunabashiChiba274- 8510Japan. Dwango CG Research KADOKAWA Hongo Bldg.5-24-5 HongoBunkyo-kuTokyo113-0033Japan.

Acquiring accurate scattering properties is important for rendering translucent materials. In particular, the phase function, which determines the distribution of scattering directions, plays a significant role in the appearance of a material. We propose a distinctive scattering theory that approximates the effect of single scattering to acquire the non-parametric phase function from a single image. Furthermore, in various experiments, we measured the phase functions from several real diluted media and rendered images of these materials to evaluate the effectiveness of our theory.

关键词： scattering phase function measurement rendering