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排序方式: 共有635条查询结果,搜索用时 15 毫秒
41.
42.
In this paper, we present a new learning method using prior information for three-layered neural networks. Usually when neural networks are used for identification of systems, all of their weights are trained independently, without considering their interrelation of weight values. Thus the training results are not usually good. The reason for this is that each parameter has its influence on others during the learning. To overcome this problem, first, we give an exact mathematical equation that describes the relation between weight values given by a set of data conveying prior information. Then we present a new learning method that trains a part of the weights and calculates the others by using these exact mathematical equations. In almost all cases, this method keeps prior information given by a mathematical structure exactly during the learning. In addition, a learning method using prior information expressed by inequality is also presented. In any case, the degree of freedom of networks (the number of 相似文献
43.
Tajima T Takiguchi N Kato J Ikeda T Kuroda A Ohtake H 《Journal of Bioscience and Bioengineering》2003,96(2):149-153
The nematode Caenorhabditis elegans exhibits chemotaxis toward a wide variety of chemicals including water-soluble molecules and volatile organic compounds. We have previously discovered that C. elegans wild-type strain N2 is strongly attracted by cycloheximide which has long been known as a bitter tastant for humans and other mammals. We describe here the isolation and initial characterization of the first mutants which were defective specifically in their attraction to cycloheximide. In our screenings, we selected two mutants that were defective in chemotaxis to cycloheximide but normal in their attraction to NH4Cl and histidine. These mutants also avoided quinine hydrochloride, CuSO4 and high concentrations of NaCl similar to the wild-type strain N2. Furthermore, no observable defect was detected in their attraction to volatile odorants such as isoamyl alcohol and diacetyl. Dye-filling experiments suggested that they have no morphological defect in the sensory endings of the amphid neurons. 相似文献
44.
We propose a synthesis method of optical Hadamard transformer using multimode interference (MMI) couplers. By using the signal transfer matrix of 2 x 2, 4 x 4, and 8 x 8 MMI couplers, we show that sum and difference units of input signals can be synthesized. An interchange unit of two signals can also be synthesized. One synthesis method of Hadamard transformers is a combination of only 2 x 2 units, and the other is a combination of N x N(N > or = 4) units as well as 2 x 2 units. The design examples of operation units are shown, and the size and the output power of Hadamard transformers are estimated. 相似文献
45.
John Dines Hui Liang Lakshmi Saheer Matthew Gibson William Byrne Keiichiro Oura Keiichi Tokuda Junichi Yamagishi Simon King Mirjam Wester Teemu Hirsimäki Reima Karhila Mikko Kurimo 《Computer Speech and Language》2013,27(2):420-437
In this paper we present results of unsupervised cross-lingual speaker adaptation applied to text-to-speech synthesis. The application of our research is the personalisation of speech-to-speech translation in which we employ a HMM statistical framework for both speech recognition and synthesis. This framework provides a logical mechanism to adapt synthesised speech output to the voice of the user by way of speech recognition. In this work we present results of several different unsupervised and cross-lingual adaptation approaches as well as an end-to-end speaker adaptive speech-to-speech translation system. Our experiments show that we can successfully apply speaker adaptation in both unsupervised and cross-lingual scenarios and our proposed algorithms seem to generalise well for several language pairs. We also discuss important future directions including the need for better evaluation metrics. 相似文献
46.
Mountain streams that originally supported Hawaiian cultural practices have been diverted for development, agriculture and tourism for over 150 years. Habitat characteristics and benthic macroinvertebrate community responses to water withdrawal were studied in four West Maui Mountain watersheds. We compared riffle and cascade habitats upstream and downstream of the highest‐elevation diversion in each stream and further compared streams to understand variation among watersheds. Riffles were shallow areas with moderate flow, whereas cascades had high‐velocity water flowing over boulders and were separated into torrenticolous (submerged) and amphibious (splash zones on adjacent exposed rock) microhabitats. Among streams, downstream discharge was reduced by 84–99%, flow velocity was four times greater upstream, and depth was 50% lower downstream. There was a significant 44% reduction in downstream macroinvertebrate density (t = 3.261, df = 136, p = 0.0014); however, density did not significantly differ among streams (F = 1.95, df = 3, p = 0.125). Habitat‐corrected density, based on total available habitat area, indicated significantly greater proportions of native taxa in amphibious microhabitats compared with riffle and torrenticolous habitats. Non‐native Chironomidae and Trichoptera (Cheumatopsyche sp. and Hydroptila sp.) were dominant (>95%) and ubiquitous in riffles, whereas native Limonia sp. dominated (30%) amphibious microhabitats. Macroinvertebrate community structure varied among streams, sites and microhabitats, indicating inconsistent response to water withdrawal, dependent upon watershed size and microhabitat conditions. Our findings contribute to water management and restoration efforts focused on conservation of native species and habitat integrity in tropical streams worldwide. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
47.
Tae Ho Lee Hirokazu Aoki Yasushi Sugano Makoto Shoda 《Journal of Bioscience and Bioengineering》2000,89(6):545
The production of dye-decolorizing peroxidase (DyP) was investigated by cultivating Geotrichum candidum Dec1 using molasses as a carbon source. Molasses at concentrations greater than 10 g·l−1 was found to increase the decolorization activity of the culture broth toward dye, reactive blue 5 mainly because the amount of enzyme produced was enhanced. However, complete inhibition of DyP activity by molasses was observed at the concentration of 20 g·l−1, indicating that the inhibitory effect of molasses on the culture broth activity to decolorize the dye was involved. When the culture broth was diluted 25 times, the dye-decolorizing activity was 7 times as much as that of non-diluted culture broth. The molasses fractions separated by gel chromatography (300–400 ml and 400–500 ml fractions) completely inhibited the purified DyP. On the basis of these results, we propose a scheme to control both positive and negative effects of molasses on the dye decolorization process. 相似文献
48.
Photoelectrochemical decomposition of bio-related compounds such as amino acids was investigated with a biophotochemical cell comprising a mesoporous TiO2 thin film photoanode and an O2-reducing cathode. It was concluded that a kind of Schottky junction formed at the surface of the TiO2 (called as liquid junction) induced the photodecomposition followed by generation of photocurrent/photovoltage. Complete photodecomposition was investigated by the CO2 formation yield. The photocurrent-photovoltage (J-V) characteristics of amino acids and other typical bio-related compounds were investigated, and the short circuit photocurrent (Jsc), open circuit photovoltage (Voc), and Fill factor (ff) were exhibited. Effect of pH on the photodecomposition of phenylalanine and cysteine were studied; for cysteine alkaline conditions gave a high efficiency, which was interpreted by the high electron-donating ability of the dissociated -S− group. The incident light-to-current conversion efficiency (IPCE) of cysteine was 25% at 350 nm. It was for the first time shown that organic acids gave high internal quantum efficiency (η′) over 8 (=800%) in the photodecomposition; for oxalic acid it was 9.3 (=930%) and for butyric acid 8.2. The alternating current impedance spectroscopy of glycine showed that the cell performance is determined by the chemical reactions at TiO2 or Pt electrodes. 相似文献
49.
50.
Sintering Kinetics at Isothermal Shrinkage: Effect of Specific Surface Area on the Initial Sintering Stage of Fine Zirconia Powder 总被引:1,自引:0,他引:1
Koji Matsui Akira Matsumoto Masato Uehara Naoya Enomoto Junichi Hojo 《Journal of the American Ceramic Society》2007,90(1):44-49
The isothermal shrinkage behaviors of fine zirconia powders (containing 2.8–2.9 mol% Y2 O3 ) with specific surface areas of about 6 and 16 m2 /g were investigated to clarify the effect of specific surface area on the initial sintering stage. The shrinkage of powder compact was measured under constant temperatures in the range of 1000°–1100°C. The increase in specific surface area enhanced the densification rate with increasing temperature. The values of activation energy ( Q ) and frequency-factor term (β0 ) of diffusion at initial sintering were estimated by applying the sintering-rate equation to the isothermal shrinkage data. The Q of diffusion changes little but the β0 increases with the increase in specific surface area. It is therefore concluded that the increase in the specific surface area of fine zirconia powder enhances the shrinkage rate because of an increase in the β0 at the initial stage of sintering. 相似文献