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11.
Modified quadratic discriminant functions and the application to chinese character recognition 总被引:8,自引:0,他引:8
Kimura F Takashina K Tsuruoka S Miyake Y 《IEEE transactions on pattern analysis and machine intelligence》1987,(1):149-153
Issues in the quadratic discriminant functions (QDF) are discussed and two types of modified quadratic disriminant functions (MQDF1, MQDF2) which are less sensitive to the estimation error of the covariance matrices are proposed. The MQDF1 is a function which employs a kind of a (pseudo) Bayesian estimate of the covariance matrix instead of the maximum likelihood estimate ordinarily used in the QDF. The MQDF2 is a variation of the MQDF1 to save the required computation time and storage. Two discriminant functions were applied to Chinese character recognition to evaluate their effectiveness, and remarkable improvement was observed in their performance. 相似文献
12.
Hydrogenation of four bituminous coals impregnated with 5 wt% of either mixtures of ZnCl2-MCln (CuCl, CrCl3 and MoCl5) systems or ZnCl2 was carried out using a batch autoclave system at 400° for 3 h at 9.8 MPa of initial hydrogen pressure. The ZnCl2-MoCl5 system showed the highest yield of the hexane-soluble (HS) fraction compared with the other systems irrespective of the coal used. The difference between the yields of HS fractions using the ZnCl2-MoCl5 and other systems was most marked for coals of fairly low volatile matter content, though the conversion was relatively low (47–66%), whilst for coals of high volatile matter content HS yields with the binary melt systems were high (86–91% conversion). Elemental analyses of the HS fractions indicated that the ZnCl2-MoCl5 system is most favourable in decreasing the average molecular weight and the heteroatom content of HS, this characteristic trend being confirmed also with five HS fractions separated by Chromatographic techniques. Both elemental analyses and molecular weights of asphaltene (benzene-soluble materials, BS) indicated that the ZnCl2-MoCl5 system is also most effective in cracking coal structure. 相似文献
13.
Na-oyoshi Iwasaki Takanori Miyake Eriko Yagasaki Toshimitsu Suzuki 《Catalysis Today》2006,111(3-4):391-397
Attention has been increasingly paid to the partial oxidation of lower alkanes to synthesis gas, due to its intrinsic energy saving process. We studied the partial oxidation of ethane (POE) on Co loaded on various supports. The POE performance varied as follows: Y2O3, CeO2, ZrO2, La2O3 SiO2, Al2O3, TiO2 > MgO. Comparing Y2O3 and CeO2, the carbon deposition during the POE was negligible on CeO2 and therefore CeO2 was the most preferable support. By changing space velocity and O2 partial pressure, reaction mechanism of POE was studied and it was revealed that two-step mechanism was prevailing; combustion of ethane to H2O and CO2 and subsequent reforming of ethane with H2O and CO2 to synthesis gas. Co/CeO2 catalyst exhibited high and stable catalytic activity for 10 h; high ethane conversion of 18% (maximum ethane conversion 20% at O2/C2H6 = 0.2) with H2 and CO selectivities of 93 and 84%, respectively. 相似文献
14.
Natural objects often contain vivid color distribution with wide variety of colors. Conventional colorization techniques, on the other hand, produce colors that are relatively flat with little color variation. In this paper, we introduce a randomized algorithm which considers not only the value of target color but also the distribution of target color. In essence, our algorithm paints a color distribution to a region which synthesizes color distribution of a natural object. Our approach models the correlation between intensity and color in HSV color space in terms of H – S, H – V and S – V joint histogram. During the colorization process, we randomly swap and reassign color of a pixel to minimize a cost function that measures color consistency to its neighborhood and intensity‐to‐color correlation captured in the joint histogram. We tested our algorithm extensively on many natural objects and our user study confirms that our results are more vivid and natural compared to results from previous techniques. 相似文献
15.
Riho Kataishi Takayuki Ikeda Toshiki Sasaki Kouhei Toyotaka Daiki Nakamura Hiroyuki Miyake Yuji Iwaki Kazunori Watanabe Yuichi Yanagisawa Hisao Ikeda Harue Nakashima Nobuharu Ohsawa Shingo Eguchi Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Daisuke Kurosaki Masakatsu Ohno Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2014,22(8):381-392
In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen. 相似文献
16.
This paper aims to assess quantitatively the actual visual environment of uncontrolled urban downtown intersections in Japan in relation to frequently occurring crossing collisions and to discuss the safety countermeasures for them. In Field Study 1 dealing with direct visibility, our ultra-wide-angle photograph analysis revealed that most of the right/left-ward visible range at 11 intersections were insufficient to check safety, and the quality of direct visibility was closely associated with causing crossing collisions. The countermeasures to reduce a blind area were determined to be a top priority. In Field Study 2 dealing with indirect visibility, more than half of the 25 traffic convex mirrors had marked shortcomings for preventive safety, and ergonomics guidelines ensuring indirect visibility were proposed for installing traffic convex mirrors. Low-cost/low-technology-oriented countermeasures are highly recommended to obtain clear/sufficient images of crucial information satisfying drivers' requirements on traffic convex mirrors in accordance with those ergonomics guidelines was highly recommended. Crossing collisions could be prevented by improvement of poor direct and indirect visibility. 相似文献
17.
Watanabe M Takemasa I Kawaguchi N Miyake M Nishimura N Matsubara T Matsuo E Sekimoto M Nagai K Matsuura N Monden M Nishimura O 《Proteomics. Clinical applications》2008,2(6):925-935
In the development of novel biomarkers, the proteomic approach is advantageous because using it the cancer-associated proteins can be directly identified. We previously developed a 2-nitrobenzenesulfenyl (NBS) method to improve quantitative proteome analysis. Here, we applied this method to proteomic profiling of colorectal carcinoma (CRC) to identify novel proteins with altered expression in CRC. Each pair of tumor and normal tissue specimens from 12 CRC patients was analyzed, and approximately 5000 NBS-labeled paired peaks were quantified. Peaks with altered signal intensities (>1.5-fold) and occurring frequently in the samples (>70%) were selected, and 128 proteins were identified by MS/MS analyses as differentially expressed proteins in CRC tissues. Many proteins were newly revealed to be CRC related; 30 were reported in earlier studies of CRC. Six proteins that were up-regulated in CRC (ZYX, RAN, RCN1, AHCY, LGALS1, and VIM) were further characterized and validated by Western blot and immunohistochemistry. All six were found to be CRC-localized, either in cancer cells or in stroma cells near the cancer cells. These results indicate that the proteins identified in this study are novel candidates for CRC markers, and that the NBS method is useful in proteome mining to discover novel biomarkers. 相似文献
18.
19.
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
20.
Masashi Kato Tomonari Yasuda Keiko Miyake Masaya Ichimura Tomoaki Hatayama 《International Journal of Hydrogen Energy》2014
Solar-to-hydrogen conversion efficiencies of water-splitting photochathodes using epitaxially grown p-type 4H-, 6H- and 3C-SiC were estimated in a two-electrode system without applying any external bias. By using electrode materials with small oxygen overpotentials as counter electrodes, the photocurrent became comparable to that observed in a three-electrode system with a suitable bias. Estimated efficiencies seem to depend on the bandgap of the SiC polytypes. For the 3C-SiC, the obtained efficiency was 0.38%, which is so far the highest value reported for SiC. We confirmed that the hydrogen volumes estimated from the photocurrent were almost the same as actual volumes observed by gas chromatography. 相似文献