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排序方式: 共有428条查询结果,搜索用时 15 毫秒
101.
Yuefei Ma Takaaki Tsurumi Noriaki Shinoda Osamu Fukunaga 《Diamond and Related Materials》1995,4(12):1325-1330
The variation of diamond nucleation density as a function of the conditions of bias enhanced nucleation (BEN) were studied. The nucleation density increased with microwave power, but decreased with the substrate temperature. The nucleation density also increased with bias voltage above 60 V, and had a maximum around 100 V. The crystal growth of diamond took place when either the bias voltage was high or the deposition time was long. The shift of C1s energy measured by X-ray photoelectron spectroscopy indicated that the ratio of carbon sp3 bonds in the amorphous carbon and/or SiC phases formed before the nucleation of diamond, increased around the bias voltage of 100 V, which seemed to be the reason for enhancement of diamond nucleation by bias voltage. A simple computer simulation was performed in order to understand the effect of BEN conditions on the nucleation of diamond. The simulation reproduced the experimentally observed changes of nucleation density and particle size. 相似文献
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103.
Shoko Hira Akiko Matsumoto Ken Kihara Sakuichi Ohtsuka 《Journal of the Society for Information Display》2019,27(7):409-426
The mutual understanding of color‐normal observers (CNOs) and color‐defective observers (CDOs) is now essential because personal color information display environments have been widely adopted. However, existing tools for CDOs offer only color discrimination; they fail to support color impression (ie, saturation and contrast). Therefore, we need a novel tool that offers help in distinguishing opponent colors, while preserving color saturation. We introduce two key techniques for realizing this difficult goal. The former is the repeated sequential display of the original and processed images to support the formation of unified correct percepts that provide discrimination of both red‐green and yellow‐blue opponent colors. One image, ie, original, exhibits correct yellow‐blue but distorted red‐green information for CDOs while the other, ie, processed, provides synthesized distinguishable red‐green but confusable yellow‐blue information for CDOs; here, hue rotation (HR) is useful for advanced users whereas hue blending (HB) is suitable for general. The latter is realized by the real‐time video processing available on smartphones; our algorithms support direct processing of the digital component video signal formats (eg, Y, CR, and CB). Subjective tests suggest that the two above‐mentioned algorithms will, along with embedding a lightweight real‐time dichromatic simulation facility for CNOs, greatly help the mutual understanding of CNOs and CDOs. 相似文献
104.
Nonparametric discriminant analysis 总被引:4,自引:0,他引:4
Fukunaga K Mantock JM 《IEEE transactions on pattern analysis and machine intelligence》1983,(6):671-678
A nonparametric method of discriminant analysis is proposed. It is based on nonparametric extensions of commonly used scatter matrices. Two advantages result from the use of the proposed nonparametric scatter matrices. First, they are generally of full rank. This provides the ability to specify the number of extracted features desired. This is in contrast to parametric discriminant analysis, which for an L class problem typically can determine at most L 1 features. Second, the nonparametric nature of the scatter matrices allows the procedure to work well even for non-Gaussian data sets. Using the same basic framework, a procedure is proposed to test the structural similarity of two distributions. The procedure works in high-dimensional space. It specifies a linear decomposition of the original data space in which a relative indication of dissimilarity along each new basis vector is provided. The nonparametric scatter matrices are also used to derive a clustering procedure, which is recognized as a k-nearest neighbor version of the nonparametric valley seeking algorithm. The form which results provides a unified view of the parametric nearest mean reclassification algorithm and the nonparametric valley seeking algorithm. 相似文献
105.
Fukunaga K Flick TE 《IEEE transactions on pattern analysis and machine intelligence》1983,(4):410-416
Given a general n-dimensional bimodal Gaussian mixture, this paper shows how unknown parameters may be found by the method of moments. Three cases are considered-equal modal probabilities, known but not necessarily equal probabilities, and all parameters unknown. The solution involves sample moments no higher than fourth order. For Gaussian mixtures where the number of modes is unknown, fourth-order moments can be used to count them, provided all modes have the same covariance matrix, and their multiplicity is not greater than data dimensionality. Examples of mode-counting and the determination of bimodal parameters are included. 相似文献
106.
Masaya Tamaki Yoko Fukunaga Masashi Mitsui Kazuyuki Maeda Masaaki Kabe Yasuyuki Teranishi Takayuki Nakanishi Hideyuki Omori Shuji Hayashi Naoyuki Takasaki Fumitaka Goto Tsutomu Harada 《Journal of the Society for Information Display》2014,22(5):251-259
A 7.03‐in. extended graphics array reflective LCD prototype has been developed by using memory‐in‐pixel (MIP) technologies with a newly designed system and pixel structure. The MIP system comprising a MIP backplane and a display driver has been optimized to reduce power consumption. The MIP backplane has specific circuits that allow accessing row drivers randomly, and the display driver manages which row should be accessed. Thus, the system is capable of showing a mixture of still and moving images, resulting in low power consumption. A dithering block embedded in the display driver enables to select an appropriate dithering algorithm according to the types of images and the position on the screen. In addition, the novel pixel structure, “three divided patterns”, has been designed to improve image quality and to provide visibility in dark environments. The latter is based on a novel approach; interpixel area is used for an aperture to transmit light from the backlight, and the fringe field from adjacent pixel electrodes is used to control LC directions. The feature of the pixel structure is also effective for obtaining equivalent gamma between reflective and transmissive images. 相似文献
107.
Variation of the gel region with heat-treatment and variation of the melt-quenched glass region with cooling rates were compared for the B2O3-Na2O-TiO2 system. Gels were prepared by the sol-gel method without catalyst using boron tributoxide (B(OBu)3) sodium methoxide (NaOCH3) and titanium tetraisopropoxide (Ti(OPr)4). The gel region was in the composition range B2O3 = 0 to 90, Na2O = 0 to 60, and TiO2 = 0 to 100 mol % at 50 ° C. The crystalline phases precipitated were boric acid (H3BO3), sodium metaborate hydrate (NaBO22H2O), and sodium hydroxide (NaOH), or sodium carbonate (Na2CO3). A 500 °C, heat treatment for 2 h reduced the gel regions to a composition range of B2O3 = 50 to 90, Na2O = 10 to 30 and TiO2 = 0 to 20 mol %, but treatment at 800 ° C produced melts which became glassy upon cooling. On the other hand, a twin-roller method produced a wide range of glass region which includes a high concentration of TiO2 up to 70 mol %. The as-prepared gel region was found to correspond fairly well to the twin-roller glass region and the thermally most stable gel region was close to the air-quenched glass region. It was speculated that the B2O3- or Na2O-rich composition had not gelled because of the high water solubility of these gels. 相似文献
108.
109.
110.
Glutamate-induced phosphorylation of myristoylated alanine-rich protein kinase C substrate (MARCKS) was investigated in cultured rat hippocampal neurons. In 32P-labeled hippocampal neurons, exposure to 10 microM glutamate induced a long lasting increase in phosphorylation of MARCKS. The long lasting increase in MARCKS phosphorylation mainly required activation of the N-methyl-D-aspartate receptor. Unexpectatively, the MARCKS phosphorylation after the 10-min incubation with glutamate was not inhibited by treatment with calphostin C, a potent inhibitor for protein kinase C (PKC), or down-regulation of PKC but was largely prevented by PD098059, a selective inhibitor for mitogen-activated protein (MAP) kinase kinase. In contrast, the phosphorylation following the short exposure to glutamate was prevented by a combination of PD098059 and calphostin C. The phosphopeptide mapping and immunoblotting analyses confirmed that PKC-dependent phosphorylation of MARCKS was transient and the MAP kinase-dependent phosphorylation was relatively persistent. Investigations of the functional properties also showed that the MARCKS phosphorylation by MAP kinase regulates its calmodulin-binding ability and its interaction with F-actin as seen in the PKC-dependent phosphorylation. These results suggest that glutamate causes a long lasting increase in MARCKS phosphorylation through activation of the N-methyl-D-aspartate receptor and subsequent activation of MAP kinase in the hippocampal neurons. 相似文献