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Study on the Ultrastructures of Antennal Sensilla in Helicoverpa armigera

The 1st chinese Conference on Trusted Computing and Information Security

作者： LI Guang-hui, LI Xiao-wei School of Information Engineering, Zhejiang Forestry College, Hangzhou 311300, Zhejiang, china institute of Computing Technology, chinese academy of sciences, beijing 100080, china Graduate School of the chinese academy of sciences, beijing 100039, china

＜正＞ We present a formal method of verifying designs with unknown constraints （e. g. , black boxes） using Boolean satisfiability （SAT）. This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form （CNF） formulas. Furthermore, this method can avoid the potential memory explosion, which the binary decision diagram （BDD） based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

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Agricultural sciences in china 2002年第8期1卷 896-899页

作者： WANG Gui-rong, GUO Yu-yuan and WU Kong-ming( State Key Laboratory of Plant Disease and Insect Pests, The institute of Plant Protection , chinese academy of Agricultural sciences, beijing 100094 , P. R . china ) State Key Laboratory of Plant Disease and Insect Pests The Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100094 P. R . China

The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus, pedicel and flagellum that the latter consists of 70 - 82 segments. The inner side surface of antenna is cat-aphracted and most of the antennal sensilla lie on its outer, upper and lower surfaces. Both the antennae of male and female contain five kinds of antennal sensilla, namely, sensillum trichodeum, sensillum basicon-icum, sensillum chaeticum, ear-shaped sensillum and sensillum coeloconicum, and the kinds, number and distribution of antennal sensilla of both sexes are similar. There are a large number of serrate cuticular processes on antennal surface, especially on the middle and basic parts of antenna. Sensillum trichodeum and sensillum basiconicum, the main chemical odor receptors on antennae of Helicoverpa armigera, consist of cuticular-wall, sheath cells, lymph and dendrites. There are significant differences between the internal structures of the two kinds of sensilla. In sensillum trichodeum, the cuticular-wall is thicker, less lipophilic pore channels and has one or a few dendrites, while in sensillum basiconicum, the cuticular-wall is thinner, abundant lipophilic pore channels and has much more dendrites.

关键词： Helicoverpa armigera Antennal sensillum Ultrastructures Scanning electron microscope Transmission electron microscope

A NEW LOW-COST DEMODULATOR FOR 2.4 GHZ ZIGBEE RECEIVERS

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Journal of Electronics(china) 2009年第2期26卷 252-257页

作者： Yu Yunfeng Meng Xin Xiao Shimao Ma Chengyan Ye Tianchun institute of Microelectronics of chinese academy of sciences（CAS） beijing 100029 china Hangzhou Microelectronics of chinese academy of Science Ltd. Hangzhou 310053 china

A new low-cost demodulator for ZigBee receivers satisfying requirements of IEEE802.15.4 standard is presented,which is designed for ISM 2.4 GHz band and based on Zero-IF *** demodulator extracts symbols directly from baseband signal rather than recovering PN code chips,so its structure is *** main techniques are used to improve the performance of *** is Phase-Axis Crossing Detector(PACD) which detects the phase correlation of baseband *** other is symbol synchronization and sampling clock correction *** result shows that this demodulator performance,Symbol Error Rate(SER) and Packet Error Rate(PER) meet IEEE 802.15.4TM standard requirements and the demodulator can handle frequency offset in excess of 200 kHz,involving a Zero-IF receiver with a Noise Figure(NF) lower than 17 dB,which is easily imple-mented in standard CMOS technology.

关键词： ZigBee Demodulator Minimum Shift Keying(MSK) Low-cost Symbol synchronization

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用于ADSL中的变步长LMS算法

通信学报 2002年第3期23卷 78-83页

作者：杨学贤张群英侯紫峰中国科学院计算技术研究所北京100080 中国科学院电子学研究所北京100080

本文给出了一种改进的LMS算法,该算法可应用于非对称数字用户线中实现回波抵消功能,从而在低频段的子通道内同时传输上行和下行的数据。新算法利用误差信号的相关值调节算法步长,具有较好的抗干扰性能,解决了算法收敛时间和稳态误差间... 详细信息

本文给出了一种改进的LMS算法,该算法可应用于非对称数字用户线中实现回波抵消功能,从而在低频段的子通道内同时传输上行和下行的数据。新算法利用误差信号的相关值调节算法步长,具有较好的抗干扰性能,解决了算法收敛时间和稳态误差间的矛盾,为实际应用提供了更大的控制灵活性。仿真结果表明,在低信噪比的环境中,改进算法的收敛速度和稳态误差等性能指标都有较大的提高,并对随机出现的脉冲干扰表现出较好的鲁棒性。

关键词：非对称数字用户线 LMS算法自适应滤波通信网

The challenge of wide application of information and communication technologies to traditional location theory

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Journal of Geographical sciences 2013年第2期23卷 315-330页

作者： SONG Zhouying LIU Weidong Key Laboratory of Regional Sustainable Development Modeling of the chinese academy of sciences institute of Geographic sciences and Natural ResourcesResea—rch CASBeijing100101China

The wide application of information and communication technologies （ICTs） has been argued to be critical to spatial transformation of firms. Recent advances in the studies along this line have challenged traditional location theory. The existing literature, however, focuses mainly on the impacts of ICTs on Iocational conditions and industrial spatial distribution. The dynamics behind such changes have not yet been given sufficient attention by geographers. Given this background, this paper investigates the impact of new ICTs on traditional location theory and the dynamics of industrial re-location that are enabled by new ICTs, based on data collected from an investigation of 178 firms. The paper argues that the application of new ICTs has been a key location factor in the information age, and that the time-cost is becoming critical to the spatial organization of firms, particularly as a result of a shorter product life and mass customization, among other dynamics.

关键词： information and communication technologies location factor time-cost

Cratonization and the Ancient North china Continent:A summary and review

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Cratonization and the Ancient North China Continent:A summar...

Two granitic plutons in Central Western Kunlun Belt: Their ages and possible sources

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： ZHAI MingGuo~* Key Laboratory of Mineral Resources,institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china

Cratonization is a key geological process to form stable continental masses with a considerable *** Precambrian global cratonization and formation of supercratons in the world is an unrepeated event in the history of the Earth’s formation and *** based on study of early Precambrian geology in Eastern Hebei Region and combining other Archean regions in the North china Craton(NCC),the author proposes a two-stage cratonization model of the *** first stage took place at the end of Neoarchean of～2.5 Ga(boundary time between Archean and Proterozoic),when several micro-blocks were amalgamated together with amphibohte-granuhte facies metamorphism and intrusion of crustal-melting granites to form the present-scale *** second cratonization event is cratonic reworking,corresponding to rifting-subduction-collision at 2.3-1.97 Ga and subsequent extension-uplifting related to upwelling mantle at 1.97-1.82 Ga,which could be linked to,respectively, assembly and breaking up of the Columbia *** main Paleoproterozoic mobile belts in the NCC record that small remnant Neoarchean ocean basins and continental rift basins within the craton were opened and finally closed, and metamorphosed to greenschist-amphibolite facies at～2.0-1.97 *** that,high-grade granulite facies(HT-HP and HT-UHT) metamorphism with abnormally high heat occurred at 1.97-1.82 Ga.A metamorphism-migmatization event that includes lower crust of the NCC uplifting as a whole,intrusion of mafic dyke swarms,continental rifting and anorogenic magmatic action took place in 1.82-1.65 Ga,marking that the second cratonization of the NCC was finally accomplished and started to evolve to a period of stable continent(platform).

关键词： cratonization North china ancient continent

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Science Bulletin 1999年第19期 3-5页

作者： YUAN Chao, SUN Min and LI Jiliang Department of Earth sciences , The University of Hong Kong , Hong Kong , china institute of Geology, chinese academy of sciences , beijing 100029, china

Geochronological and isotope studies have been carried out for two important plutons in the Central Western Kunlun Belt. U-Pb single grain zircon dating results show that the North Kudi Pluton (404 Ma) was produced near the end of Caledonian; whereas the previously labeled Hercynian Arkarz Mountain Pluton (215 Ma) is either an Indosinian pluton or a product of

关键词： granitic pluton. Central Western Kunlun Belt.

LAMOST Project and Its Scientific Goals

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天文研究与技术 1999年第S1期 1-7页

作者： Zhao Yongheng (beijing Astronomical Observatory, chinese academy of sciences, beijing 100012, china yzhao  lamost. bao. ac. cn)

The LAMOST is a meridian reflecting Schmidt telescope with a clear aperture of 4 meter, a focal length of 20 meter and a field of view of 5 degree. Using active optics technique to control its reflecting corrector makes LAMOST an unique astronomical instrument in combining a large aperture with a wide field of view. The available large focal plane of 1.75 meter in diameter may accommodate up to 4000 fibers, by which the collected light of distant and faint celestial objects down to 20.5 magnitude is fed into the spectrographs, promising a very high spectrum acquiring rate of several ten thousands of spectra per night. The spectroscopic survey carried out by LAMOST of tens of millions of glaxies and others will make substantial contribution to the study of extra galactic astrophysics and cosmology, such as galaxies, quasars and the large scale structure of the universe. Its spectroscopic survey of large number of stars will make substantial contribution to the study of stellar astrophysics and the Galaxy. Its spectroscopic survey combining with the surveys in other wavebands, such as radio, infrared, X ray and γ ray will make substantial contribution to the cross identification of multi waveband of celestial objects.

关键词： LAMOST Project and Its Scientific Goals Project SPIE

Dispersion Compensators Based on Overlaped Linearly Chirped Fiber Gratings for DWDM Systems

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chinese Journal of Lasers 2001年第6期10卷 18-22页

作者： LI Tangjun Ning Tigang WANG Muguang JIAN Shuisheng (institute of Lightwave Technology, Northern Jiaotong University, beijing 100044, china) 北方交通大学光波所北京 100044

By introducing a convergent lens in the phase mask setup and by tilting appropriately the fiber from the phase mask, a linearly chirped fiber grating with an appropriate chirp can be obtained conveniently. Using this method, two groups of fiber gratings, each of them is composed of 8 overlaped linearly chirped fiber gratings but with different center reflection wavelength separations (～0.8 nm and ～1.6 nm, respectively) are fabricated. Experimental results show that, the compensators based on the two groups of fiber gratings can be used to compensate for the dispersion of 8×2.5 Gb/s transmission over 100 km of standard single-mode fiber for multiple channels in optical time-division multiplexing (OTDM) and densed wavelength division multiplexing (DWDM).

关键词： fiber grating OTDM DWDM