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51.
Nobuhiko Tamura Norimichi Tsumura Yoichi Miyake 《Journal of the Society for Information Display》2003,11(2):333-339
Abstract— A color management system (CMS) such as ICC profile or sRGB space have been proposed for color transformation and reproduction of cross media. In such a CMS, accurate colorimetric characterization of a display device plays a critical role in achieving device‐independent color reproduction. In the case of a CRT, colorimetric characterization based on a GOG model is accurate enough for this purpose. However, there is no effective counterpart in liquid‐crystal displays (LCDs) since the characterization of an LCD has many difficulties, such as channel interaction and non‐constancy of channel chromaticity. In this paper, a new method of display characterization is proposed which is applicable to the assessment of color reproduction of LCDs. The proposed method characterizes an electro‐optical transfer function considering both channel interaction and non‐constancy of channel chromaticity. Experimental results show that the proposed method is very effective in the colorimetry of LCDs. 相似文献
52.
Maruo K. Tsurugi M. Chin J. Ota T. Arimoto H. Yamada Y. Tamura M. Ishii M. Ozaki Y. 《IEEE journal of selected topics in quantum electronics》2003,9(2):322-330
This paper reports in vivo near-infrared (NIR) noninvasive blood glucose assay using dermis tissue spectra. We assume that the glucose content in dermis tissue traces the variations in blood glucose. For dermis spectra measurements, epidermis, especially stratum corneum, acts as an interference in skin tissue. Thus, we have developed a method for the selective measurement of dermis tissue spectra, enabling us to obtain better quality spectra for an accurate blood glucose assay. The selective measurement of the dermis spectra realized by using a newly developed fiber-optic probe that consists of source and detector optical fibers separated by 0.65 mm on a skin surface. The light path in the skin tissue for this geometry has been simulated by a Monte Carlo method. The simulation results show that detected light mainly interrogates dermis tissue. As the absorbance signal of glucose in human tissue is extremely small, the quality of the measured spectra is critical for the reliable assay. The present method for blood glucose assay has been applied to one Type 1 diabetic. The correlation coefficient between the blood glucose content predicted by NIR spectra and those measured by finger-prick was 0.928 and the standard error of prediction was 32.2 mg/dL. These results demonstrate the potential of our methodology for noninvasive NIR blood glucose assay. 相似文献
53.
Application of an ultrahigh-resolution scanning electron microscope (UHS-T1) to biological specimens
Keiichi Tanaka Akira Mitsushima Yuzuru Kashima Takashi Nakadera Hitoshi Osatake 《Microscopy research and technique》1989,12(2):146-154
In 1985 we developed an ultrahigh-resolution scanning electron microscope with a resolution of 0.5 nm. It is equipped with a field emission gun and an objective lens with a very short focal length. In this study we report a survey of some different preparation techniques and biological specimens using the new scanning electron microscope. Intracellular structures such as cell organelles were observed surprisingly sharper than those observed by ordinary scanning electron microscopes. However, at magnifications over 250,000 X, platinum particles could be discerned as scattered pebbles on the surface of all structures in coated materials. Using an uncoated but conductively stained specimen, we successfully observed ribosomes on a rough endoplasmic reticulum at a direct magnification of 1 million. In these images some protrusions were recognized on the ribosomes. Ferritin and immunoglobulin G were used as samples of biological macromolecules. These samples were observed without metal coating and conductive staining. The ferritin particles appeared as rounded bodies without any substructure on the surface and immunoglobulin G as complexes of three-unit bodies. In the latter the central body might correspond to the Fc fragment and two side ones to Fab fragments. We assume that ultrahigh-resolution scanning electron microscopy is an effective means for observation of the cell fine structures and biological macromolecules. It will open a new research field in biomedicine. 相似文献
54.
In order to observe intracellular structures by scanning electron microscopy, excess cytoplasmic matrix must be removed from the fractured surface of cells. Previously we reported an Osmium-DMSO-Osmium method devised for this purpose. This method is very effective in revealing intracellular structures, but requires osmium tetroxide for initial fixation with some consequent disadvantages. In the present study, a revised Osmium-DMSO-Osmium method is reported, in which an aldehyde mixture is used as the initial fixative instead of osmium tetroxide. As fixation is carried out by perfusion in this revised method, better preservation of fine structures is achieved than by the original method, especially in the central nervous tissue which tends to suffer from post-mortem degeneration. Moreover this method can be applied to cytochemical studies of intracellular structures with a scanning electron microscope (SEM). In this study, acid phosphatase of lysosomes is demonstrated in a coloured SEM micrograph. 相似文献
55.
Voltage Control of Static Var Compensator for a Remote System Interconnected by Long‐Distance AC Cables
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Yuji Tamura Shinji Takasaki Yasuyuki Miyazaki Hideo Takeda Shoichi Irokawa Kikuo Takagi Naoto Nagaoka 《Electrical Engineering in Japan》2014,186(3):19-30
The voltage variation in a remote system is large when the system is connected by long‐distance AC cables due to the cable capacitance. In Japan, the longest 54‐km 66‐kV AC submarine cable interconnection between the Kyushu mainland and Goto Islands was commissioned in 2005. It was requested to mitigate the voltage variation caused by switching off and on one circuit of the two circuits in the AC cables when a fault occurs. Since the conventional voltage control methods such as transformer tap changer or shunt capacitor and reactor banks are not sufficient because of their slow response time, a static var compensator (SVC) was installed on the Goto Islands. In such an application, an SVC control method should be developed so as not to override the existing voltage control systems. This paper describes the SVC control method developed for the Goto Islands AC interconnection project, which can be applied to similar situations. The effectiveness of the control method was verified by the results of effective value simulation and of field testing, which was implemented before the SVC was commissioned in 2007. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 19–30, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22337 相似文献
56.
H. Furuta Y. FukudaT. Hara T. Haruna N. IshiharaM. Ishitsuka C. ItoM. Katsumata T. KawasakiT. Konno M. KuzeJ. Maeda T. MatsubaraH. Miyata Y. NagasakaK. Nitta Y. SakamotoF. Suekane T. SumiyoshiH. Tabata M. TakamatsuN. Tamura 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,662(1):90-100
We carried out a study of neutrino detection at the experimental fast reactor JOYO using a 0.76 tons gadolinium loaded liquid scintillator detector. The detector was set up on the ground level at 24.3 m from the JOYO reactor core of 140 MW thermal power. The measured neutrino event rate from reactor on-off comparison was 1.11±1.24(stat.)±0.46(syst.) events/day. Although the statistical significance of the measurement was not enough, backgrounds in such a compact detector at the ground level were studied in detail and MC simulations were found to describe the data well. A study for improvement of the detector for future such experiments is also shown. 相似文献
57.
Hiroki Uehara Takuya Tamura Masaki Kakiage Takeshi Yamanobe 《Advanced functional materials》2012,22(10):2048-2057
Crystalline homopolymers, including polyethylene (PE), which has the simplest architecture, form a nanometer‐sized combination of crystalline and amorphous components, but their arrangement control, similar to self‐assembled phase‐separation of block‐copolymers, is usually difficult. However, molecular entanglements trapped between crystalline and amorphous components of homopolymers coincide with the segmental linking points on the interfaces of the microphase separation for block copolymers. Nanowrinkled PE membranes are prepared with a network of 30 nm‐thick homogeneous lamellae using a novel entanglement control technique composed of biaxial melt‐drawing and melt‐shrinking procedures, which are limited for highly entangled ultrahigh molecular weight materials. Such a network arrangement of nanowrinkling lamellae spreading on membrane surface and also across the membrane thickness improves the mechanical properties of both tensile strength and tearing strength. Subsequent cold‐drawing causes delamination of the lamellar interfaces, leading to the resultant nanoporous morphology composed of passing‐through channels that are several tens of nanometers in diameter, without any solvent processing. 相似文献
58.
59.
Mohammad Abul Hossain Shahidul Islam Farzana A. Chowdhury Tariq G. Mohiuddin Koji Uchida Takahiro Tamura 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(1):43-51
We studied the elemental analysis, structural morphology, mechanical, and electrical properties of carbon nanoparticles synthesized from diesel. The spherical carbon particle size in the range of about 10 to 80 nm in diameter was observed in scanning electron microscope (SEM) studies that were identified by Atomic force microscopy (AFM) study as an aggregation of carbon particles of average size 2.5 nm. The surface rms of carbon nanoparticle thin film (CNTF) was measured directly by AFM and found 0.22 nm. The Derjaguin–Muller–Toporov (DMT) elastic modulus of carbon nanoparticles (CNPs) was measured by PeakForce QNM mode of AFM. The minimum and maximum elastic modulus was measured of 0.40 GPa and 43.89 GPa, respectively. The resistivity, conductivity, magneto resistance, mobility, and average Hall co-efficient were measured by “Ecopia Hall-effect measurement system” by four-point Van der Pauw approach at ambient condition. We demonstrated I–V characteristic at the Indium/CNTF thin film interface, which is accompanied by rectifying behavior. 相似文献
60.
Thawhid Khan Shunsuke Koide Yukio Tamura Hiroshi Yamamoto Ardian Morina Anne Neville 《Tribology Letters》2018,66(1):43
Oxy-nitriding is a widely used industrial process aiming to improve the tribological properties and performance of components. Previous studies have shown the effectiveness of the treatment with friction and wear performance, but very few have focussed on optimising this behaviour. The lubrication properties of several EP and AW additives were examined to investigate their effectiveness in improving the tribological properties of the layers formed after treatment. Previous studies showed the presence of an oxide layer on the sample could improve the effectiveness of the sulphurised olefin (SO) and tricresyl phosphate (TCP) additives. The friction and wear behaviour of oxy-nitrided samples were analysed using a tribometer and surface profiler. Scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy were employed to identify the morphologies and chemical compositions of the treated surface before and after testing. No real effect on friction was observed when using the SO or TCP additives, mostly due to lack of interaction with the less reactive iron nitride layer and their roles as anti-wear additives. However, when the zinc dialkyldithiophosphate-containing lubricant was used, a higher friction coefficient was observed. Greater improvements in anti-wear properties with the presence of additives in comparison with only using base oil were reported, with the TCP additive producing the lowest wear rates. The study effectively demonstrated that the additive package type used could impact the tribological and tribochemical properties of oxy-nitrided surfaces. 相似文献