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Progress in Natural Science:Materials International 2004年第10期14卷 35-39页

作者： SONG Weiqun 1,3. ,GAO Yuan 1 and LUO Yuejia 1,2 (1.Key Laboratory of Mental Health,Institute of Psychology,Chinese Academy of Sciences,Beijing100101,China 2.School of Psy-chology,southwest China Normal University,Chongqing400715,China 3.Graduate School of the Chinese Academy of Sciences,Bei-jing10003.,China) Chinese Acad Sci Inst Psychol Key Lab Mental Hlth Beijing 100101 Peoples R China SW China Normal Univ Sch Psychol Chongqing 400715 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

The visual attention mechanism in the brain was studied among16young subjects through the precue-target visual search paradigm using the event-related potentials(ERPs)technique,with the attentive ranges cued with different scales of Chinese *** results showed that the response time was shortened as the cue scale was reduced,while the amplitudes of the P1and N1components of the ERPs *** results not only provided the electrophysiological evidence supporting the spotlight theory,but also indicated that the spotlight effect occurred during the early period of the selected *** kinds of separation in the P2effect were *** separation was between the P1effect and P2effect,which meant that additional computation was needed when the spatial scale of attention was enlarged;the other was between the left and right hemisphere of the P2effect,which indicates that the at-tentive processing of the cue range mainly occurred in the left hemisphere.

关键词： visual spatial attention cue scale spotlight effect hemisphere superiority event-related potential(ERP)

Distribution　and　Transformation　of　Native　and　Added　Ni　Fractions　in　Purple　Soils　from　Sichuan　Province

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Pedosphere 1996年第2期6卷 183-192页

作者： TU CONG(College of Resources and Environment,southwest Agricultural University,Chonyqiny 63.716 China) College of Resources and Environment Southwest Agricultural University Chongqing 630716 China

The distribution and transformation of added and native Ni in purple soils were investigated with both sequential extraction procedure and isotopic tracer *** distribution of added and native Ni was greatly dependent on soil *** soil PH was favorable for soluble plus exchangeable (EX) Fraction,while Fe/Mn oxides and clay for Fe/Mn oxide bound (OX) and residual (RES) fractions. The added Ni,however,has not yet reached the distribution equilibrium up to the 150th day after *** was reflected in the fact that the proportion of EX fraction from added Ni was 150%-600% as much as that of native Ni, while that of RES fraction was only about 80%.Once entering soil, the applied soluble Ni was rapidly transformed into Other fractions, but the organic complexed (OM) fraction of added Ni was relatively stable during *** carbonate bound(CAB) fraction showed a progressive increase and attained a peak value after 0-14 d of incubation and thereafter decreased gradually. The occurrence time of this peak advanced as initial soil PH increased, but the peak would disappear when initial soil pH was higher than 7.5(or containing free CaCO3.. The transformation processes of the EX,OX and RES fractions could be described by Elovich and two-constant rate equstions,and the rates were positively correlated with soil pH,CEC and *** findings could explain why there are differences in ecological and environmental effects of Ni in different soils and at various intervals.

关键词： distribution Ni fraction purple soil tracer technique transformation

Forecast Method of Multimode System for Debris Flow Risk Assessment in Qingping Town,Sichuan Province,China

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Journal of Mountain Science 2011年第4期8卷 592-602页

作者： KONG Jiming Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The Wenchuan Earthquake of May 12,2008 triggered large numbers of *** heavy rain on 13.August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroyed 500 houses and infrastructure built after the Wenchuan *** study area Qingping Town was located in the northwestern part of the Sichuan Basin of China,which needs the second reconstructions and the critical evaluation of debris *** study takes basin as the study unit and defines collapse,landslide and debris flow hazard as a geo-hazard system.A multimode system composed of principal series system and secondary parallel system were established to evaluate the hazard grade of debris flow in 13. drainage basins of Qingping *** evaluation result shows that 3..43. of study basins(42 basins) and 24.58% of study area,are in extremely high or high hazard grades,and both percentage of basin quantity and percentage of area in different hazard grades decrease with the increase of hazard *** to the geo-hazard data from the interpretation of unmanned plane image with a 0.5-m resolution and field investigation after the Wenchuan Earthquake and 8.13.Big Debris Flow,the ratio of landslides and collapses increased after the Wenchuan Earthquake and the ratios of extremely high or high hazard grades were more than moderate or low hazard grades obviously.23.geo-hazards after8.13.Big Debris Flow in Qingping town region all occurred in basins with extremely high or high hazard grades,and 9 debris flows were in basins with extremely high hazard *** model of multimode system for critical evaluation could forecast not only the collapse and landslide but also the debris flow precisely when the basin was taken as the study unit.

关键词： Multimode System Risk assessment Debris flow Landslide Wenchuan Earthquake Qingping Town

Interactions between hotspots and the southwest Indian Ridge during the last 90 Ma:Implications on the formation of oceanic plateaus and intra-plate seamounts

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Science China Earth Sciences 2011年第8期54卷 1177-1188页

作者： ZHANG Tao 1,2,3.4,LIN Jian 5 & GAO JinYao 3.4 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 43.077,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3.The Second Institute of Oceanography,State Oceanic Administrator,Hangzhou 3.0012,China 4 Key Laboratory of Submarine Geosciences,State Oceanic Administrator,Hangzhou 3.0012,China 5 Department of Geology and Geophysics,Woods Hole Oceanographic Institution,Woods Hole,MA 02543.USA 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. The Second Institute of Oceanography State Oceanic Administrator Hangzhou 310012 China4. Key Laboratory of Submarine Geosciences State Oceanic Administrator Hangzhou 310012 China

This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the southwest Indian *** first calculated the relative distance between the southwest Indian Ridge (SWIR) and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy *** results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction (73.6-68.5 Ma),interaction with the SWIR (68.5-42.7 Ma),and intra-plate volcanism (42.7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,*** magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge *** periodicity of the Marion hotspot is about 25 Ma,which is much longer than that of the Hawaii and Iceland hotspots (about 15 Ma).

关键词： southwest Indian Ocean hotspot-ridge interaction magmatic volume flux oceanic plateaus seamounts

A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： ZHU ZhiWu, NING JianGuo& MA Wei 1 School of Mechanics and Engineering, southwest Jiaotong University, Chengdu 61003., China 2 State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China 3.Key Laboratory of Frozen Soil Engineering, CAREERI, CAS, Lanzhou 73.000, China 1. School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Key Laboratory of Frozen Soil Engineering CAREERI CAS Lanzhou 730000 China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temperature conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temperature and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temperature field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results support the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in permafrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field

A NEW SPECIES OF VALSA

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Journal of Northeast Forestry University 1991年第2期2卷 105-108页

作者： Zhao Guangcai Sheng Shifa Li Nan southwest Forestry College, Kunming 1. southwest Forestry College Kunming

The papr has reported a new species of Valsa came from the twigs andbranches of Cryptomeria fortunei Hooibrenk ex Otto et *** was named as Valsa forunea Zhao,Sheng et *** *** it is in the perfect stage and Cytospora fortunea Zhao,Sheng et *** the imperfect *** new species has been described both in Latin and in Chinese,aswell as the differences between the new species and other *** type specimen of the newspecies is deposited in the plant pathology Herbarium of southwest Forestry College,Kunming(HSFC 15206 Type).

关键词： Valsa Cylospora Valsa fortunea Cylospora fortunea Cryplomeria fortunei

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多码CDMA ALOHA系统及性能分析

西南交通大学学报 2004年第6期39卷 768-771页

作者：潘甦刘曙光邱波南京邮电学院通信工程系江苏南京210003 中国联通江苏分公司江苏南京210003 西南交通大学网络教育学院四川成都610031

提出了一种基于ALOHA和多码CDMA技术的多码CDMAALOHA系统,用以支持多速率数据通信.分析了该系统在高斯噪声信道的吞吐量性能并进行了仿真.仿真和分析结果表明,由于综合了ALOHA和多码CDMA技术的优点,多码CDMAALOHA系统能支持多速率数据... 详细信息

提出了一种基于ALOHA和多码CDMA技术的多码CDMAALOHA系统,用以支持多速率数据通信.分析了该系统在高斯噪声信道的吞吐量性能并进行了仿真.仿真和分析结果表明,由于综合了ALOHA和多码CDMA技术的优点,多码CDMAALOHA系统能支持多速率数据业务且具有较好的性能.

关键词： CDMA 多码系统 ALOHA

A NEW WELL TEST MODEL FOR STRESS-SENSITIVE AND RADIALLY HETEROGENEOUS DUAL-POROSITY RESERVOIRS WITH NON-UNIFORM THICKNESSES

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Journal of Hydrodynamics 2011年第6期23卷 759-766页

作者： ZHANG Lie-hui, GUO Jing-jing, LIU Qi-guo State Key Laboratory of Reservoir Geology and Exploitation, southwest Petroleum University, Chengdu 610500, China State Key Laboratory of Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China

This article presents a new well test model for stress-sensitive composite dual-porosity reservoirs based on the concept of permeability modulus, where the rock and fluid properties as well as the formation thickness vary in the radial direction. An analytical solution in the Laplace space for the pressure-transient behavior for a line-source, constant-rate well of this type of reservoir is obtained with the Laplace transformation and the perturbation technique. The pressure and its derivative in the reservoir and the effects of relevant parameters on the pressure-transient response are obtained. The model as well as the corresponding type curves may be used in predicting the production performance or analyzing the production data for this type of reservoir.

关键词： non-uniform thickness stress-sensitive composite dual-porosity well test model type curve

Experimental study of CT test on the failure of acrylate spray-applied waterproof layer in the groundwater environment

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Science China(Technological Sciences) 2010年第2期53卷 512-518页

作者： YANG QiXin, XU Peng & ZHENG ShangFeng 1 School of Civil Engineering, southwest Jiaotong University, Chengdu 61003., China 1. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.

关键词： spray-on waterproof layer scan CT number failure groundwater environment

Centroid-based semi-fragile audio watermarking in hybrid domain

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Science China(Information Sciences) 2010年第3期53卷 619-633页

作者： WANG HongXia & FAN MingQuan School of Information Science and Technology, southwest Jiaotong University, Chengdu 61003., China 1. School of Information Science and Technology Southwest Jiaotong University Chengdu 610031 China

Many previous (semi-) fragile audio watermarking schemes adopt binary images as watermarks, which reduce the security of watermarking systems. On the other hand, the content-based or feature-based second generation digital watermarking has limited applicability, and its partial feature points may be damaged by watermarking operations and various common signal processing. To overcome these problems, in this paper, a novel centroid-based semi-fragile audio watermarking scheme in hybrid domain is proposed. The theoretical lower limit of signal to noise ratio (SNR) for objective evaluation of the imperceptibility of watermarked audio signal is deduced, and the watermark embedding capacity and the tamper detection ability are theoretically analyzed. In the proposed scheme, first, the centroid of each audio frame is computed, then Hash function is performed on the obtained centroid to get the watermark, after that, the audio sub-band which carries centroid of audio frame is performed with discrete wavelet transform (DWT) and discrete cosine transform (DCT), and finally the encrypted watermark bits are embedded into the hybrid domain. Theoretical analysis and experimental results show that the proposed scheme is inaudible and applicable to different types of audio signals. Furthermore, its ability of tamper detection and tolerance against common signal processing operations are excellent. Comparing with the existing schemes, the proposed scheme can effectively authenticate the veracity and integrity of audio content, and greatly expand the applicability of the content-based audio watermarking scheme.

关键词： semi-fragile audio watermarking centroid inaudibility tamper detection