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排序方式: 共有389条查询结果,搜索用时 10 毫秒
291.
Muneharu Kuwata Hiroaki Sugiura Tomohiro Sasagawa Atsushi Michimori Eiich Toide Takayuki Yanagisawa Syuhei Yamamoto Yoshihito Hirano Masahiro Usui Shigenori Teramatsu Jun Someya 《Journal of the Society for Information Display》2009,17(11):875-882
Abstract— A high‐definition laser TV that employs a newly developed laser light source and a super‐wide‐angle projection optical system has been developed. This adoption of a laser light source with three primary colors helped to achieve an extremely wide color gamut, and, in addition, a compact optical engine, which has been optimized to the laser light source and contributed to the achievement of the stylish design of a large screen of 65 in., with the depth being only 255 mm. 相似文献
292.
Surface Characterization of Zirconia After Reaction with Water 总被引:1,自引:0,他引:1
Masahiro Kagawa Mamoru Omori Yasuihiko Syono Yoko Imamura Shinnosuke Usui 《Journal of the American Ceramic Society》1987,70(9):212-C
Ultrafine ZrO2 , Y2 O3 , and TZP (ZrO2 +-3 mol% Y2 O3 ) powders were reacted with water under various conditions; hydration of their particle surfaces was investigated by measuring electrophoretic mobilities. The mobilities were independent of pH after the reaction at 250° to 300°C for 240 h, indicating that the surface is not hydrated. Refluxing of the powders in water for 170 h brought about a pH dependence of mobility, indicating hydration of the surface. 相似文献
293.
Mutation-based genetic neural network 总被引:2,自引:0,他引:2
Evolving gradient-learning artificial neural networks (ANNs) using an evolutionary algorithm (EA) is a popular approach to address the local optima and design problems of ANN. The typical approach is to combine the strength of backpropagation (BP) in weight learning and EA's capability of searching the architecture space. However, the BP's "gradient descent" approach requires a highly computer-intensive operation that relatively restricts the search coverage of EA by compelling it to use a small population size. To address this problem, we utilized mutation-based genetic neural network (MGNN) to replace BP by using the mutation strategy of local adaptation of evolutionary programming (EP) to effect weight learning. The MGNN's mutation enables the network to dynamically evolve its structure and adapt its weights at the same time. Moreover, MGNN's EP-based encoding scheme allows for a flexible and less restricted formulation of the fitness function and makes fitness computation fast and efficient. This makes it feasible to use larger population sizes and allows MGNN to have a relatively wide search coverage of the architecture space. MGNN implements a stopping criterion where overfitness occurrences are monitored through "sliding-windows" to avoid premature learning and overlearning. Statistical analysis of its performance to some well-known classification problems demonstrate its good generalization capability. It also reveals that locally adapting or scheduling the strategy parameters embedded in each individual network may provide a proper balance between the local and global searching capabilities of MGNN. 相似文献
294.
Analytical prediction of cutting tool wear 总被引:2,自引:0,他引:2
An analytical method is presented which enables the crater and flank wear of tungsten carbide tools to be predicted for a wide variety of tool shapes and cutting conditions in practical turning operations based only on orthogonal cutting data from machining and two wear characteristic constants. A wear characteristic equation is first derived theoretically and verified experimentally. An energy method is developed to predict chip formation and cutting forces in turning with a single-point tool from the orthogonal cutting data. Using these predicted results, stress and temperature on the wear faces can be calculated. Computer simulation of the development of wear is then carried out by using the characteristic equation and the predicted stresses and temperatures upon the wear faces. The predicted wear progress and tool life are in good agreement with experimental results. 相似文献
295.
Suzuki K Daikoku S Ako T Shioiri Y Kurimoto A Ohtake A Sarkar SK Kanie O 《Analytical chemistry》2007,79(23):9022-9029
Collision-induced dissociation (CID) in mass spectrometry is a powerful technique with which to understand gas-phase chemical reactions. A mass spectrometer is used to carry out the reaction, isolation, and analysis. On the other hand, structural analysis of glycan structures is of extreme importance in the analysis of biomolecules, such as glycoproteins and glycolipids. In the analysis of glycan structures based on CID, certain ion species, including B-/Y-, C-/Z-, and A-/X-ions, are produced. Among these ions, we are interested in C-ion species that carry a glycosyl oxygen atom at the anomeric center and that possibly provide information regarding anomeric configuration. A method for generating C-ion species when necessary is thus considered to be important; however, none is currently available. In this study, synthetic glycosides carrying a series of aglycons were analyzed with the aim of identifying suitable glycosides with which to produce C-ions to be used in the structural determination of oligosaccharides. The results showed a 4-aminobutyl group was an excellent candidate. Furthermore, the use of C-ion species obtained in this manner in the structural characterization of a ganglioside, GM3, is described. The type of glycoside is believed to be valuable not only in structural analysis but also in biological investigation, because of the existing amino functionality that has been proven to be useful by enabling the generation of conjugates with other molecules and materials. 相似文献
296.
Usui Y Aoki K Narita N Murakami N Nakamura I Nakamura K Ishigaki N Yamazaki H Horiuchi H Kato H Taruta S Kim YA Endo M Saito N 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(2):240-246
Carbon nanotubes (CNTs) have been used in various fields as composites with other substances or alone to develop highly functional materials. CNTs hold great interest with respect to biomaterials, particularly those to be positioned in contact with bone such as prostheses for arthroplasty, plates or screws for fracture fixation, drug delivery systems, and scaffolding for bone regeneration. Accordingly, bone-tissue compatibility of CNTs and CNT influence on bone formation are important issues, but the effects of CNTs on bone have not been delineated. Here, it is found that multi-walled CNTs adjoining bone induce little local inflammatory reaction, show high bone-tissue compatibility, permit bone repair, become integrated into new bone, and accelerate bone formation stimulated by recombinant human bone morphogenetic protein-2 (rhBMP-2). This study provides an initial investigational basis for CNTs in biomaterials that are used adjacent to bone, including uses to promote bone regeneration. These findings should encourage development of clinical treatment modalities involving CNTs. 相似文献
297.
Atsuko Nakanishi Akari Minami Yasuko Kitagishi Yasunori Ogura Satoru Matsuda 《International journal of molecular sciences》2015,16(2):2879-2892
Tumor suppressor molecules play a pivotal role in regulating DNA repair, cell proliferation, and cell death, which are also important processes in the pathogenesis of Alzheimer’s disease. Alzheimer’s disease is the most common neurodegenerative disorder, however, the precise molecular events that control the death of neuronal cells are unclear. Recently, a fundamental role for tumor suppressor molecules in regulating neurons in Alzheimer’s disease was highlighted. Generally, onset of neurodegenerative diseases including Alzheimer’s disease may be delayed with use of dietary neuro-protective agents against oxidative stresses. Studies suggest that dietary antioxidants are also beneficial for brain health in reducing disease-risk and in slowing down disease-progression. We summarize research advances in dietary regulation for the treatment of Alzheimer’s disease with a focus on its modulatory roles in BRCA1 and p53 tumor suppressor expression, in support of further therapeutic research in this field. 相似文献
298.
Morito Akiyama Chao-Nan Xu Masaya Kodama Ichiro Usui Kazuhiro Nonaka Tadahiko Watanabe 《Journal of the American Ceramic Society》2001,84(9):1917-1920
Highly c -axis-oriented aluminum nitride (AlN) thin films were prepared on polycrystalline Si3 N4 and SiC substrates by helicon plasma sputtering. The difference in the substrate materials scarcely influenced the crystal structures of the films. The full width at half-maximum (FWHM) of the X-ray rocking curves of the films was 3.2°, which is the smallest value for AlN thin films deposited on polycrystalline substrates to our knowledge. Annealing at 800°C in vacuum decreased the FWHM from 3.2° to 2.8°. The structure of the films was densely packed and consisted of many fibrous grains. The films developed c -axis orientation on the polycrystalline substrates, because the interaction between the films and substrate surfaces was small, and (100) and (110) AlN planes grew preferentially. The films were piezoelectric and generated electrical signals in response to mechanical stress. 相似文献
299.
Mikito Higashi Takeshi Yoshimura Noriyoshi Usui Yuichiro Kano Akihiro Deguchi Kazuhiro Tanabe Youichi Uchimura Shigeki Kuriyama Yasuyuki Suzuki Tsutomu Masaki Kazuhiro Ikenaka 《International journal of molecular sciences》2020,21(23)
Detection of early-stage hepatocellular carcinoma (HCC) is beneficial for prolonging patient survival. However, the serum markers currently used show limited ability to identify early-stage HCC. In this study, we explored human serum N-glycans as sensitive markers to diagnose HCC in patients with cirrhosis. Using a simplified fluorescence-labeled N-glycan preparation method, we examined non-sialylated and sialylated N-glycan profiles from 71 healthy controls and 111 patients with hepatitis and/or liver cirrhosis (LC) with or without HCC. We found that the level of serum N-glycan A2G1(6)FB, a biantennary N-glycan containing core fucose and bisecting GlcNAc residues, was significantly higher in hepatitis C virus (HCV)-infected cirrhotic patients with HCC than in those without HCC. In addition, A2G1(6)FB was detectable in HCV-infected patients with early-stage HCC and could be a more accurate marker than alpha-fetoprotein (AFP) or protein induced by vitamin K absence or antagonists-II (PIVKA-II). Moreover, there was no apparent correlation between the levels of A2G1(6)FB and those of AFP or PIVKA-II. Thus, simultaneous use of A2G1(6)FB and traditional biomarkers could improve the accuracy of HCC diagnosis in HCV-infected patients with LC, suggesting that A2G1(6)FB may be a reliable biomarker for early-stage HCC patients. 相似文献
300.
Poly(hexamethylene biguanide) (PHMB) is of interest as a bactericide for fabrics. It has affinity for cotton by reaction with the cellulosic carboxylate groups. In this study, the capacity of undyed cotton to absorb PHMB has been determined and compared with cotton dyed with anionic bis(monochlorotriazinyl) reactive dyes. When cotton is dyed with these dyes the absorption of PHMB increases, the dye providing sulphonic acid sites with which the PHMB can react. The reacted PHMB and the percentage fixation of reactive dye were determined and from this the concentration of sulphonic acid on the dyed fibre. In the case of cotton dyed with Procion Yellow H-E4R, the dye increased the absorption of PHMB to approximately 1.45 mequiv. of biguanide per sulphonic acid group. For Procion Red H-E3B and Navy H-ER the figures were 1.18 and 1.00, respectively. 相似文献