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Statistical distribution of nonlinear random wave height

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Science China Earth sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1. GUO Peifang1.2. SONG Guiting1.2. SONG Jinbao1. YIN Baoshu1.& ZHAO Xixi1.2.1. {3. of Oceanology, chinese academy of sciences, Qingdao 2.6071. China 2. Graduate University of the chinese academy of sciences, Beijing 1.003., China 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate University of the{1. Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East China Normal University are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science China Earth sciences 2005年第5期48卷 585-600页

作者： YANG Wencai 1., YANG Wuyang 1., JIN Zhenmin 2.& CHENG Zhenyan 1.1. {1. of Geology, chinese {2. of Geological sciences, Beijing 1.003., China 2. China University of Geosciences, Wuhan 43.074, China 1. chinese {1. of Geological {2. Institute of Geology 100037 Beijing China 2. China University of Geo{1. 430074 Wuhan China

Calibration of seismic reflectors appearing in the crust of the chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 1. km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu China, calibration of reflectors, lithospheric fabrics.

Prediction method for October 2.0{1.solar storm

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Science China(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1. 2. {1. WEI Fengsi1. FENG Xueshang1.& ZHONG Dingkun1. 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, Beijing 1.0080, China 2. Graduate School, chinese academy of sciences, Beijing 1.00{1., China {1. {2. of Meteorology, PLA University of Science and Technology, Nanjing 2.1.01. China State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1. and 3.1., re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3. 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, China 2. Graduate University of chinese academy of sciences, Beijing 100049, China 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 1.01.1. China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical {1. Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of {1. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1.2., GUO Qionglin~1.*, HU Wei~1. WANG Yaping~1.and ZHU Zuoyan~1.1. State Key Laboratory of Freshwater Ecology and Biotechnology, {1. of Hydrobiology, chinese academy of sciences, Wuhan 43.072. China 2. Graduate School of chinese academy of sciences, Beijing 1.003., China) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]Graduate School of chinese academy of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1.06 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 3.4 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 3.0} bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 3.0} bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

General inverse of Stokes, Vening-Meinesz and Molodensky formulae

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Science China Earth sciences 2006年第5期49卷 499-504页

作者： CHENG Luying1.2.& XU Houze1.1. {1. of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, China 2. Xi’an Research {1. of Surveying and Mapping, Xi’an 71.054, China 1. institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China 2. Xi’an Research {1. of Surveying and Mapping Xi’an 710054 China

The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes’ formula, the general inverse Vening-Meinesz formula and the general Molodensky’s formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degen- erated into the classic ones.

关键词： spherical harmonics, boundary value problem, general inverse Stokes' formula, general inverse Vening-Meinesz formula, general Molodensky's formula.

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1.2.**, ZHANG Hongfu~1. XIAO Yan~ 1.2.and ZHAO Xinmiao~ 1.2.(1. State Key Laboratory of Lithospheric Evolution, {3. of Geology and Geophysics, chinese academy of sciences, Beijing 1.002., China 2. Graduate School of chinese academy of sciences, Beijing 1.003., China) [a]State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1.. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

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归一化模型在人类认知活动中的应用

应用心理学 2024年

作者：孙阳阳罗鑫宇周柳芳李海燕孙彦良 1.山东师范大学心理学院 2.上海外国语大学国际工商管理学院 {1.山东大学齐鲁医院神经外科山东师范大学心理学院上海外国语大学国际工商管理学院山东大学齐鲁医院神经外科

神经计算模型是深入解析神经元信息编码过程的重要方法。近年来，归一化模型(normalization model)作为一种新兴神经计算方法，在人类认知活动中广泛应用。此模型基于当前反应神经元的活动与神经元池活动总和的比率，来揭示神经元的实... 详细信息

神经计算模型是深入解析神经元信息编码过程的重要方法。近年来，归一化模型(normalization model)作为一种新兴神经计算方法，在人类认知活动中广泛应用。此模型基于当前反应神经元的活动与神经元池活动总和的比率，来揭示神经元的实际响应。最初用于解析初级视觉皮层中的神经元活动，随后在感知觉和注意机制研究中得到了充分的验证和应用，但在高级认知活动研究中的应用仍显不足。展望未来，归一化模型在高级认知活动研究中的应用值得进一步拓展。

关键词：归一化模型感觉注意决策工作记忆

Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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Science China Earth sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1. PENG Suping1. ZHANG Zhongjie2.& LIU Zhenkuan{1.1. China University of Mining & Technology, Beijing 1.008{1. China 2. institute of Geophysics,{{1., Beijing {2. China {1. Exploration and Development Research institute of Daqing Oilfield, Daqing 1.{1.1.0} China 1. China University of Mining & Technology Beijing 100083 China 2. {1. of Geophysics Chinese Academy of Sciences Beijing 100101 China 3. Exploration and Development Research {1. of Daqing Oilfield Daqing 163712 China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.