维普中文期刊产品整合服务
394篇 您的检索式:作者名="12"
    题名 作者 年代 出处 被引量
1Study on detection of coastal water environment of China by ocean color remote sensing显示文摘Coastal water environment is essentially enhanced by ocean color which is basically decided by substances concentration in water such as chlorophyll, suspended material and yellow substance. It is very difficult, even not possible, to detect water color by expensive ship routing, because of its temporal and spatial variety of feature and scales in the very complicated dynamical system of coastal water. With the development of satellite technique in the last 20 a, space sensors can be applied to detect ocean color by measuring the spectra of water leaving radiance.It is proven that ocean color remote sensing is a powerful tool for understanding the process of oceanic biology and physics. Since the 1980s, great attention has been paid to the advanced remote sensing technique in China, especially to development of satellite programs for the coastal water environment. On 7 September 1988, China launched her first polar orbit satellite FY-1A for meteorological and oceanographic application (water color and temperature) and the second satellite FY-1B two years later. In May 1999, China launched her second generation environment satellite FY-1C with higher sensitivies, more channels and stable operation. The special ocean color satellite HY-1 is planned to be in the orbit in 2001, whose main purpose is to detect the coastal water environment of China seas. China is also developing a very advantageous sensor termed as Chinese moderate imaging spectra radiometer (CMODIS) with 91 channels, which will be a good candidate of the third generation satellite FY-3 in 2003. The technical system of ocean color remote sensing was developed by the Second Institute of Oceanography (SIO), State Oceanic Administration (SOA) in 1997. The system included data receiving, processing, distribution, calibration, validation and application units. The Hangzhou Station of SIO, SOA has the capability to receive FY-1 and AVHRR data since 1989. It was also a SeaWiFS scientific research station authorized by NASA,USA to free receive SeaWiFS data from 16 September 1997. In the recent years, the local algorithms of atmospheric correction and inversion of ocean color have been developed for FY-1C and SeaWiFS, to improve the accuracy of the measurement from satellites efficiently. The satellite data are being applied to monitor coastal water environment, such as the spatial distribution of chlorophyll, suspended material and yellow substance, red tide detection and coastal current study. The results show that the ocean color remote sensing has latent capacity in the detection of coastal water environment.In consideration of the update technique progress of ocean color remote sensing and its more important role in the detection of coastal water in the 2000s, some suggestions are set forth, which would be beneficial to the design of a cheaper but practical coastal water detection system for marine environment preservation.Pan Delu 1,2 , Mao Tianming 1, Li Shujing 1,Huang Haiqing 11 .LaboratoryofOceanDynamicProcessesandSatelliteOceanographyofStateOceanicAdministration ,Hangzhou310 0 12 ,China 2 .LaboratoryofSubmarineGeosciencesofStateOceanicAdministration ,Hangzhou 3 2001Acta Oceanologica Sinica2001,20,1:16
2The 3-D non-axisymmetrical Lamb's problem in transversely isotropic saturated poroelastic media显示文摘Based on Biots theory on fluid-saturated porous media, the displacement functions are adopted to convert the 3-D Biots wave equations in the cylindrical coordinate for transversely isotropic saturated poroelastic media into two棗one 6-order and one 2-order棗uncoupling differential governing equations. Then, the differential equations are solved by the Fourier expanding and Hankel integral transform method. Integral solutions of soil skeleton displacements and pore pressure as well as the total stresses for poroelastic media are obtained. Furthermore, the systematic study on Lambs problems for the transversely isotropic saturated poroelastic media is performed. Integral solutions for surface radial, vertical and circumferential displacements are obtained in both cases of drained surface and undrained surface under the vertical and horizontal harmonic excitation force. In the end of this paper, the numerical examples are presented. The calculation results indicate that the difference between the model of isotropic saturated poroelastic media and that of transversely isotropic saturated poroelastic media is obvious.HUANG Yi1 & WANG Xiaogang1,2 1. School of Civil Engineering, Xian University of Architecture & Technology, Xian 710055, China 2. Department of Civil Engineering, Qinghai University, Xining 810016, China Correspondence should be addressed to Huang Yi (email: huangyih@pub.xaonline.com) Received April 15, 2004 revised July 12, 2004 2004Science China(Technological Sciences)2004,47,5:10
3东濮凹陷沙三段盐构造类型及地震识别显示文摘东濮凹陷北部地区沙河街组第三段发育三套深湖相盐岩韵律层 ,后期因埋深和构造力作用导致盐岩流动和变形 ,进而形成许多与盐有关的构造或岩性圈闭。由于盐岩总是和深湖相泥岩共生或伴生 ,故盐岩发育区是烃源岩发育区 ,同时也是盐构造和盐圈闭发育区。由于该区具备生、储、盖、圈、保的优越条件 ,所以该区一直是人们的重点研究目标。文中介绍了该区各种与盐变形有关的构造和圈闭类型以及盐的地震反射特征和识别方法 ,并讨论了盐及盐构造对油气的控制作用。何亚伟 姚合法 段红梅 常俊合 刘亚州12 2003石油地球物理勘探2003,38,5:7
4国内12地区精神疾病流行学调查的方法学及资料分析[J]显示文摘12地区精神疾病流行学调查协作组 1986中华神经精神科杂志1986,,19:6
5Soft spectral clustering ensemble applied to image segmentation显示文摘Jianhua Jia (12) jjh163yx@163.com Bingxiang Liu (1) Licheng Jiao (2) 2011Frontiers of Computer Science2011,5,1:6
6175型无橡胶元件涡轮钻具的研制与试验显示文摘介绍了江汉石油学院井下工具研究室研制的175型无橡胶元件涡轮钻具的简况,重点叙述了这种涡轮钻具的结构特点、涡轮叶栅与叶型设计,以及涡轮节和支承节的结构设计,给出了技术性能指标。这种无橡胶元件的涡轮钻具,采用整体式4支点金属滚动球轴承、径向TC轴承、下轴悬挂式涡轮节和大扭矩叶型,具有中速、低压降等特点。现场试验表明,175型涡轮钻具的性能满足目前钻井工艺和钻井泵的要求,用它快速钻井可提高井身质量和机械钻速,缩短建井周期,减少套管磨损,降低钻井成本。Downhole Tool Research Section of Jianghan Petroleum University( Jingzhou City, Hubei Province ). , 1999, 27(12): 31~33 1999石油机械1999,27,12:5
7Behavior features of heavy metals in the Haikou Bay waters显示文摘Dissolved Cu, Ph, Zn and Cd in the Haikou Bay waters were measured to be respectively in the range concentrations of 0.47-1.16 μg/dm^3, 0. 94-- 2. 36μg/dm^3, 1.28-4.83 μg/dm^3 and 0. 005-0.072μg/dm^3; with respectively average values of 0.78μg/dm^3, 1.36μg/dm^3, 3.14 g/dm^3 and 0. 03 μg/dm^3. Dissolved Cu and Zn concentrations are relatively high at the stations near the Longkun Road Outfall for domestic sewage, the Xiuying Outfall for industry waste water and the Haidian Island Estuary, but dissolved Pb and Cd concentrations are low in these stations. The values in Other stations are comparatively homogenous. Vertical dissolved Cu, Pb and Zn concentrations at the bottom layer are higher than at the surface layer, but dissolved Cd concentration appears to be on the opposite. The measurement results of Cu, Pb, Zn and Cd in suspended particle show that particulate matters in the Haikou Bay seawater play a role in purifying heavy metals. The study on strong complexed form and non-liable form of dissolved copper show that the ratio of strong complexed form and dissolved form is about 85%, and non-liable form is very low with a value lower than 5 nmol/dm^3. Therefore, copper in the Haikou Bay seawater cannot cause influence on marine organisms.Chen Chunhua Wang Zhengfang and Lu Haiyan 1. Marine Exploitation Plan and Design Research Institute of Hainan Province, Haikou 570203, China 2. Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China (Received July 12, 1996 1999Acta Oceanologica Sinica1999,18,2:4
8A geometric Model for the Spatial Correlation of an Acoustic Vector Field in Surface-generated Noise显示文摘健全压力和在水平地成层的媒介的表面噪音的粒子速度的空间关联被表明,与一致地在海洋表面上散布的方向性的噪音来源一起。在粒子速度的评估,飞机波浪近似被用于每条事件光线。由于健全来源关联性质和它的择向性的等价,这域的空间关联的解决方案被转变成单身的方向性的来源产生的协调函数的集成。作为一典型水平地成层的媒介,在完美的波导的表面噪音被调查。正常模式和几何模型给的关联系数显示出令人满意的同意。另外,在健全压力之间的规范的协变性和粒子速度的垂直部件与声学的吸收系数成正比,当在半无穷地同类的空间的表面噪音的是零时。Yiwang Huang (1) huangyiwang@hrbeu.edu.cn Qunyan Ren (12) Ting Li (3) 2012Journal of Marine Science and Application2012,11,1:4
9A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea显示文摘On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex andHe Dehua, Wang Chunsheng, Liu Hongbin and Yang Guanming( Received July 9, 1990 accepted November 12, 1990) 1992Acta Oceanologica Sinica1992,11,2:4
10Identifying different community members in complex networks based on topology potential显示文摘Yanni Han (1) hyn@nlsde.buaa.edu.cn Deyi Li (12) Teng Wang (1) 2011Frontiers of Computer Science2011,5,1:4
11Diurnal SST warming in the Bay of Biscay:satellite measurements and model prediction显示文摘NOAA AVHRR data from the Bay of Biscay between 1988 and 1990 have been examined in order to extract information on the fluctuations of sea surface temperature (SST) at the diurnal time scale. The temporal and spatial distributions of diurnal warming in the area are obtained. The diurnal warming occurs during the summer months. Large diurnal warming in excess of 1℃ is found within 100 km along the west coast of France and within 30 km along the north coast of Spain. In the central Bay of Biscay the diurnal warming is typically about 0.5℃. The diurnal warming up to 6℃ is observed occasionally in the coastal areas where the wind speed is very low. A one-dimensional oceanic mixed-layer model has been used to simulate the diurnal warming. The results demonstrate that the diurnal warming increases with the decrease of the wind speed and the increase of the net heat flux. The comparison shows that the model results are in good agreement with the satellite measurements.Huang Weigen I. S. Robinson and N. C. Wells 1. Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China 2. Oceanography Department, Southampton University, Southampton SO9 5HN, UK (Received December 9, 1997 accepted June 12 1999Acta Oceanologica Sinica1999,18,2:4
12HYDRAULICS OF STEEP MOUNTAIN STREAMS显示文摘As water depth and roughness size are in the same order of magnitude, flow conditions in steep streams with large roughness are very complex. In this paper some of the most important equations to estimate flow resistance of steep channels are reviewed and evaluated with experimental data from other authors and with own data. Further it is shown, that the transfer of data obtained in the laboratory to field conditions is only useful, if the boundary conditions like movable bed, roughness structure and Froude-number are identical. A new relationship to determine flow resistance of high gradient streams which includes the influence of Froude-number and roughness stature is proposed in this paper and tested with own data and those from the literature.Michael ROSPORT Dr.-Ing., Institut fuer Wasserbau und Kulturtechnik, University of Karlsruhe, KaiserstraBe 12, D-76128 Karlsruhe, Germany 1997International Journal of Sediment Research1997,12,3:4
1312导联心电图机自动诊断功能临床评价规范显示文摘心电图机自动诊断功能直接影响设备的临床应用.而目前缺乏统一的12导联心电图机自动诊断功能临床评价规范。从规范适用范围、自动诊断功能判断规则、试验方法和条件及心电图数据输入等方面建立12导联心电图机自动诊断功能临床验评规范。重点阐述自动诊断功能判断规则,包括心电图特征值的准确性.自动诊断结果的解释与判断。本规范旨在为12导联心电图机自动诊断功能临床评价提供完整的技术依据。全军心血管专业委员会心脏无创检测学组 12导联心电图机自动诊断功能验评规范编写专家组 陈韵岱 2021中国医疗器械杂志2021,45,5:3
14VELOCITY FIELD AND RESISTANCE OF FLOW OVER ROUGH SURFACES WITH LARGE AND SMALL RELATIVE SUBMERGENCE显示文摘Important formulas that describe the flow field over rough surfaces with different relative submergence are summarized and explained. It turns out that the flow field over rough surfaces with small relative submergence deviates remarkably from the one with large relative submergence. Differences in flow resistance as well as velocity and turbulence intensity distribution are documented with own data and data from the literature. The inconsistency in the results of velocity distribution and flow resistance are pointed out and discussed. Finally, physically based explanations are given for the deviations of the results.Andreas DITTRICH Institut fuer Wasserbau und Kulturtechnik,Universitet Karlsruhe,Kaiserstr. 12, 76128 Karlsruhe, Germany Katinka KOLL Institut fuer Wasserbau und Kulturtechnik,Universitet Karlsruhe,Kaiserstr. 12, 76128 Karlsruhe, Germany 1997International Journal of Sediment Research1997,12,3:3
15Three dimensional diagnostic,semidiagnostic and prognostic calculations of current in the East China Sea in April of 1994显示文摘Three dimensional diagnostic,semidiagnostic and prognostic models in the σ coordinate are used to compute the current in the East China Sea with wind and hydrographic data obtained from the investigation of ocean fluxes in the East China Sea during the cruise of April 1994.The computed results show that:the density and velocity fields and so on have been adjusted when time t ≈ 23 d, i.e.,the solution of semidiagnostic calculation has been obtained.The quasi steady state solution also has been reached after about 60 d.Comparing the results of diagnostic calculation with those of semidiagnostic and prognostic calculations,it is found that they agree qualitatively.For example,they all show that:(1)The Kuroshio flows along the shelf break of 200~1 000 m isobaths;(2)In the southeastern part of the computational region there is a stronger counter current with an anticyclonic eddy;(3)The volume transport through Section PN is about 30×10 6m 3/s and so on.However there are some quantitative differences between them.For example,(1)For the semidiagnostic results the Kuroshio current is stronger and clearer than that for diagnostic results and the Kuroshio width is more narrow than that for diagnostic results.This shows that the semidiagnostic calculation can better reflect the topography effect;(2)In most computed region the vertical component of velocity intensifies for semidiagnostic result,especially on the shelf break.Comparing the results of semidiagnostic calculation with those of prognostic calculation,they agree qualitatively,and also agree quantitatively in the middle of computed region.Wang Huiqun 1,2 ,Yuan Yaochu 1,21 .KeyLaboratoryofOceanDynamicProcessesandSatelliteOceanography ,StateOceanicAdministration ,China 2 .SecondInstituteofOceanography ,StateOceanicAdministration ,POBox .12 0 7,Hangzhou 310 0 12 ,China 2001Acta Oceanologica Sinica2001,20,1:3
16Clinical significance of immunohistochemica study of P53 protein in colorectal carcinoma显示文摘AIMS To determine the clinical significance of P53 protein ex-pression in colorectal carcinoma.METHODS The expression of P53 protein in 92 colorectal car-cinomas was examined using the monoclonal antibody PAb 1801.Correlation between P53 protein expression and prognosis in col-orectal carcinoma was analyzed using log-rank test.RESULTS The frequency of P53 protein expression was 57.61%,corresponding with Dukes’ staging.Analysis of survivordata demonstrated that the survival rate of colorectal carcinomawith positive P53 protein group was lower than that of negativeP53 protein group.CONCLUSIONS We conclude that the expression of P53 pro-tein is correlated with poor prognosis in colorectal carcinoma.CHEN Da-Wei WANG Yuan-He CHEN Xue-Yun WANG Qiang GAO Han Dr.CHEN Da-Wei, Surgeon-in-Charge,Having 12 papers published.Department of General Surgery,Changzheng Hospital,Second Military Medical University,415 Feng Yang Road,Shanghai 200003 China.Correspondence to Dr.CHEN Da-Wei. 1996World Journal of Gastroenterology1996,2,1:3
17Research on acoustic holography method for identification of sound sources显示文摘This paper presents the method named acoustic holography which can be used to identify noise sources. A new formula of holography reconstruction is obtained, based on the Kirchhoff integral formula. Some simulating tests are carried out using the new formula. The comparison with other reconstruction formulas proves that the new formula is more effective. By using acoustic holography method, some interesting results about the noise of a vehicle are shown. The results proves that acoustic holography is an effective method for the identification of the complex noise sources.YANG Diange ZHENG Sifa LI Yukang LIAN Xiaomin JIANG Xiaoyu(Automotive Engineering Department, Tsinghua University Beijing 100084)(State Key Laboratory of Automotive Safety and Energy Beijing 100084)Received Dec. 12, 2000 2002Chinese Journal of Acoustics2002,21,4:2
18SOURCE RADIATION AND RESPONSES OF WAVE PROPAGATION显示文摘Recordings of seismic waves propagating from earthquake source to a station at the earth’s surface are a system response function. The convolution operator in time domain can be simplified as a multiplication operator in frequency domain. We discuss in frequency domain the separation of source, path and site effects for global scaling of earthquake source radiation. Also discussed are source scaling model, faulting mechanism, and the H/V inversion problems with crustal and near surface structures. Gross features of apparent source spectra appear to be not much region dependent although there may be difference between tectonic styles within a region of tectonic mixture for which we need further study as data accumulate. Vertical spectra may be a better approach to approximate source radiation, as it has less crustal amplification effects than horizontal spectra. The H/V ratio is evidently a comprehensive indicator of amplification effects from near surface to deep structure. This gives it potential as an inversion tool to deduce site crustal structure.CHEN Sheng zao 1 and Gail M Atkinson 2 (1. Geomatrix Consultants, Inc., 2101 Webster St., 12 th Floor, Oakland, CA 94612, USA, formerly at Dept. Earth Sciences & Ottawa Carleton Geoscience Center, Carleton University, Ottawa, Canada 2. Dept. Ea 2001Geotectonica et Metallogenia2001,25,1:2
19Channel Mismatching in Sidelobe Canceler: Limitations and Remedies显示文摘After a brief recall of the Sidelobe Canceler (SLC) working principle, including the derivation of a general formula for the Cancellation Ratio (CR), the effects of channel mismatching are investigated. In particular, curves providing CRvalues as a function of amplitude and phase channel mismatching, radar bandwidth, and jammer direction of arrival (JDOA) are provided for the cases of one and two auxiliary antennas. Subsequently, a time -space processor for performance restoration is analyzed in detail. In addition to the above mentioned quantities, the attainable CR value is expressed as a function of the space-time processor parameters. The contribution of the paper is related to the derivation of a number of mathematical equations of CR for several cases of practical interest for the radar engineer. In addition, several curves are presented to assist design of SLC systems.A. Farina and A. ProtopapaRadar Dpt Selenia S. p. A., Via Tiburtina,Km. 12,400-00131 Rome, Italy 1992Journal of Systems Engineering and Electronics1992,3,3:2
20ANALYSIS OF FLUID FIELD OF LIQUID METAL IN ELECTROMAGNETIC CENTRIFUGAL CASTING显示文摘Navier-Stokes equation and Lorentz force equation are used to calculate the fluid field of liquid metal of electromagnetic centrifugal casting(EMCC) in this paper.A field equationis given,which shows the azimuthal velocity closely relates to electrical conductivity,mag-netic density,viscosity of liquid metal and radius of casting.The results show that the sta-tionary magentic field can effectively restrain the fluid flow and the relative velocity be-tween liquid metal and casting mould and the velocity gradient at solid/liquid interface in-creases with rising magnetic density,which has a great effect on the solidification of liquidmetal and crystal growth characteristies.JIAO Yuning, LIU Qingmin, YANG Yuangsheng, HU Zhuangqi,Institute of Meta] Research, Chinese Academy of Sciences, Shenyang, ChinaGAO Yunyan, JIA Guanglin, ZHANG Guozhi, QIAO YuanjunNortheast University, Shenyang, China Manuscript received 12 May, 1994 1994Acta Metallurgica Sinica(English Letters)1994,7,2:2
返回顶部 每页显示:
共20页 首页 上一页 第1页 下一页 末页 /20 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费