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Integrated circuits are being investigated for use in as many television circuits as feasible. In Japan, considerable work has been done by different groups within the TV industry to develop ICs that will permit cost reduction, increased reliability, and simplification of assembly-line operations. This article is a report on results of the concentrated efforts made by five major television set manufacturers to develop and produce black-and-white and color receivers, in collaboration with four universities, two institutes, and seven components manufacturers. 相似文献
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Hiroshi Watanabe Eizi Yano Keita Higashida Syouichi Hasegawa Junji Takabayashi Rika Ozawa 《Journal of chemical ecology》2016,42(2):149-155
Many natural enemies of insects use honeydew as a volatile cue to locate hosts or prey, as an oviposition stimulant, and as an arrestant for foraging. The aphidophagous gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) has predacious larval stages and can be used to control aphid populations, especially in greenhouses. Previous studies have shown that the honeydew, excreted by the aphid Myzus persicae, attracts A. aphidimyza, but the crucial attractants have not been identified. Using an olfactometer, we studied behavioral responses of female A. aphidimyza to volatiles emitted from honeydew excreted by the aphid Aphis gossypii on eggplants. The volatiles attracted female midges and induced oviposition. Moreover, using gas chromatography coupled with mass spectrometry (GC/MS), we identified phenylacetaldehyde as the attractant compound in the honeydew, although it did not induce oviposition in olfactometer experiments. 相似文献
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Oxazole-containing π-conjugated polymers, an alternating copolymer of 9,9-dioctylfluorene-2,7-diyl and 2,5-bis(p-phenylene)oxazole (P(Flu-DPOxz)) and an alternating copolymer of 2,5-dialkoxy-p-phenylene and 2,5-bis(p-phenylene(oxazole)) (P(ROPh-DPOxz)), have been synthesized by Pd-catalyzed organometallic polycondensation. They were soluble in organic solvents, and had number average molecular weights of 18?600 and 24?700, respectively, in GPC analysis. P(Flu-DPOxz) and P(ROPh-DPOxz) showed UV-vis absorption peaks at about 380 nm in CHCl3. Powder XRD patterns and UV-vis data of the polymers indicated that the polymer solid was amorphous. The polymers were photoluminescent both in chloroform and in solid. In chloroform, the emission peak appeared at about 420 nm with a high quantum yield of about 70%. The polymers were electrochemically active, and electrochemical data revealed that the oxazole unit behaved as a moderate electron-accepting unit. 相似文献
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A hybrid automatic repeat request (ARQ) system (HARQ-II) with parity retransmission for error correction, which combines ARQ and forward error correction is discussed, and the successful application of these codes to HARG-II is illustrated. A method of constructing the codes whereby conventional BCH codes can be changed into separable codes is proposed. A scheme is presented that has the advantages that, the code lengths are always made equal and that even in parity retransmission new information symbols can be sent along with the necessary parity-check symbols. The performance of the proposed schemes on the binary symmetric channel is discussed. The numerical results show that they outperform conventional schemes 相似文献
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Signal-to-noise ratios (SNR's) at the output of the squarelaw detector are determined as the functions of modulation degree and bandwidth ratio of the modulating signal and the noise carrier, when the input is an amplitude-modulated noise carrier. 相似文献
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The solution characteristics of the polysaccharide (D-glucose: D-mannose: D-galactose: D-glucuronic acid = 3 : 3 : 1 : 2) which was formed from glucose by Bacillus polymyxa No. 271 were studied. The aqueous solution of the polymer had a high viscosity comparable with that of gum guar, and the viscosity was enhanced still further in the presence of acids, salts, and sugars. The polymer had a high water hold capacity, and formed a viscoelastic gel from ethanol solutions below 40% concentration. 相似文献
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This paper provides a general analysis of the transmission characteristics of a coherent PSK signal, where anM -ary coherent signal is transmitted via a repeater system composed of a cascade ofN bandpass hard limiters. The probability density function of a composite phase of the signal and noise over the system is newly derived to obtain an error probability. In addition, the comparison with the repeater system composed of a cascade ofN linear amplifiers is made to clarify the features of the transmission characteristics. It is found that the probability density function of the composite phase over the system is symmetric about each input carrier-to-noise power ratio (CNR), and it reduces to some well-known results. It is also shown that for a reasonably large input CNR in each stage, the presence of the bandpass hard limiter (BPHL) provides some improvement, but that for small input CNR it causes degradation in performance. 相似文献
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Akihiro Kitamura Koji Nakai Takashi Namekawa Masatoshi Watahiki 《Nuclear Engineering and Design》2011,241(7):2614-2623
We developed a remote control system for maintenance of in-cell type fuel fabrication equipment. The system display recreated three-dimensional information of the workspace from data obtained by laser rangefinder and conventional cameras. It has allowed us to operate a manipulator arm remotely with several control modes. In order to evaluate the effectiveness and usefulness of developed system, we implemented remote handling experiments using mock up equipment. Performance was compared for remote operation conducted using several different display and operation modes. We confirmed that the system is able to maintain in-cell fuel fabrication equipment in each display and operation mode. Times required to complete the remote operations were collected and compared in each mode. It was observed that integration of 3D information from the laser rangefinder reduced operation time and reinforced visual information during remote operation. 相似文献
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Kawashima Y Usami T Ohashi N Suenram RD Hougen JT Hirota E 《Accounts of chemical research》2006,39(3):216-220
In view of the importance of the peptide linkage in structural biology, we have carried out intensive investigations on peptide molecules consisting of a peptide linkage with one or two substituents in the gas phase by Fourier transform microwave spectroscopy, paying special attention to the internal rotation of the substituents relative to the central linkage framework. We have found that, in sharp contrast with the stiff structure around the central C-N bond of the linkage, the internal rotations of the substituents are of low frequency and thus of large amplitude and are extremely susceptible to their local environment such as the presence of other substituents. 相似文献