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Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth Sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. Nanjing Institute of Geography & Limnology, chinese academy of Sciences, Nanjing 2.0008, {2. 2. graduate school of the chinese academy of Sciences, beijing 100039, {2. 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. graduate school of the {2. academy of Sciences Beijing 100039 China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04 and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2.03, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2.03, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.2. m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

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Reconstruction of temperature series in china for the last 5000 years

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Progress in Natural Science:Materials International 2006年第8期16卷 838-845页

作者： GE Quansheng, WANG Shunbing and ZHENG Jingyun (Institute of Geographical Sciences and Natural Resources Research, chinese academy of Sciences, {2. 100101, china graduate school of the chinese academy of Sciences, beijing 100039, china) [a]chinese academy of Sciences Institute of Geographical Sciences and Natural Resources Research Beijing China [b]graduate school of the {2. academy of Sciences Beijing China

A temperature series with a 100 year resolution for the last 5000 years in china has been reconstructed by using 31 longterm temperature proxy series selected from recent publications in the last 2. years. The proxy records include pollens, stalagmites, lake-sediments, peat, ice cores and historical documents. The result reveals that in the millennial scale temperature variation it was warm in 3050-2.0 BC and it was cold in 2.0 BC-1950 AD. In the above two periods there were many stages of sub-scale temperature fluctuations. The result also shows an obvious temperature discrepancy on the century to multi-century scale between the Eastern Monsoon Region, the Qinghai-Tibet Region and the Northwestern Region in 2.50 BC, 2.50 BC, 1350 BC, 950-350 BC, 50-2.0 AD, and 550 AD. A comparison between the reconstructed series of this paper and some North Hemisphere temperature series indicates that in the longterm scale change, the temperature change in china is in phrase with that of the Northern Hemisphere during the last 5000 years, while on the century to multi-century scale there are differences at the beginning and end times, which may imply that temperature change does not occur simultaneously in different regions.

关键词： temperature series the last 5000 years china.

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Evaluation of the Interfacial Adhesion between Brittle Coating and Ductile Substrate by Cross-Sectional Indention

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材料热处理学报 2004年第5B期25卷 1187-1190页

作者： SUJian-yu ZHANGKun CHENGuang-nan InstituteofMechanics ChineseAcademyofSciencesBeijingChina／／GraduateSchooloftheChineseAcademyofSciencesBeijingChina InstituteofMechanics ChineseAcademyofSciencesBeijingChina

The cross-sectional indentation method is extended to evaluate the interfacial adhesion between brittle coating and ductile substrate. The experimental results on electroplated chromium coating/steel substrate show that the interfacial separation occurs due to the edge chipping of brittle coating. The corresponding models are established to elucidate interfacial separation processes. This work further highlights the advantages and potential of this novel indentation method.

关键词：分界面附着刻痕可锻衬底应力涂层铬钢

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A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3 & LI Gaicheng1,2.3 1. Engineering Research Center for Information Security Technology, Institute of Software, chinese Aca- demy of Sciences, beijing 100080, {2. 2. beijing Zhongke Ansheng Corporation of Information Technology, beijing 100080, {2. 3. graduate school of the chinese academy of Sciences, beijing 100039, {2. 1. Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of Information Technology 100080 Beijing China 3. graduate school of the {2. academy of Sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of Sciences, Guangzhou 510640, {2. 2. graduate University of chinese academy of Sciences, beijing 100039, {2. 3. SHRIMP isotope Laboratory, chinese academy of Geological Sciences, beijing 100037, {2. 4. Institute of Geology and Geophysics, chinese academy of Sciences, beijing 10002., {2. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate University of chinese {2. of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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Assessment of soil erosion and sediment delivery ratio using remote sensing and GIS:a case study of upstream Chaobaihe River catchment, north china

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International Journal of Sediment Research 2008年第2期23卷 167-173页

作者： Weifeng ZHOU1 and Bingfang WU2.1 Doctor candidate,graduate school of the {2. academy of Sciences(CAS),beijing 100039,china 2.Prof.,Institute of Remote Sensing Applications,{2. academy of Sciences(CAS),beijing 100101,china [a]Doctor candidate graduate school of the {2. academy of Sciences(CAS) beijing 100039 china [b]Prof. Institute of Remote Sensing Applications chinese academy of Sciences(CAS) beijing 100101 china

Soil erosion in catchment areas reduces soil productivity and causes a loss of reservoir *** parametric models have been developed to predict soil erosion at drainage basins,hill slopes and field *** well-known Universal Soil Loss Equation(USLE) represents a standardized *** reservoir,which sits on Chaobaihe River,is the main surface source of drinking water for beijing,the capital of *** and soil loss are the main reasons for sediment to enter a *** yield is assessed using a version of the universal soil loss equation modified by chinese *** year 2.01 and 2.02.data for factors in the equation are obtained from remote sensing or collected to form an analysis *** factors are computed and mapped using Geographic Information System *** on the complex database,the modified model is *** pixel-based computing the sediment yield per hydrological unit is *** model does not consider sediment deposition occurring on *** soil loss is often higher than the sum of those measured at catchment *** sediment delivery ratio(SDR) per hydrological unit is also *** study analyzes the main contributions of sediment yields on sub-basins of the Chaobaihe River to the Miyun Reservoir,and discusses the possible reasons for the difference between SDRs in 2.01 and 2.02.at different *** result shows that in the upper basin of the Miyun Reservoir,in 2.01 the area of erosion that could be neglected was 8,2.2.76 km2.the area of low erosion 3,2.9.59 km2.the area of moderate erosion 3,400.97 km2.the area of high erosion 436.89 km2.the area of strong erosion 52.19 km2.and the area of severe erosion 3.13 *** highest soil loss was 70,353 t/*** in Fengning County in 2.01,followed by 64,418 t/*** by Chicheng County in *** SDR in 2.02.was lower than that in *** main reasons are the decreasing rainfall erosivity and total runoff.

关键词： Modified USLE Gross erosion Sediment delivery ratio

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Improved K-means Algorithm for Manufacturing Process Anomaly Detection and Recognition

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武汉理工大学学报 2006年第S3期28卷 1036-1041页

作者： ZHOU Xiaomin~(1,2. PENG Wei~1 SHI Haibo~1 (1.Shenyang Institution of Automation chinese academy of Sciences,Shenyang 110016,{2., 2.graduate school,chinese academy of Sciences,beijing 100039,{2.) Shenyang Institution of Automation chinese academy of Sciences Shenyang 110016China graduate school Chinese Academy of SciencesBeijing 100039China Shenyang Institution of Automation chinese academy of Sciences Shenyang 110016China

Anomaly detection and recognition are of prime importance in process *** are usually rare,and, therefore,predicting them is *** this paper,a new greedy initialization method for the K-means algorithm is proposed to improve traditional K-means clustering *** new initialization method tries to choose suitable initial points,which are well separated and have the potential to form high-quality *** on the clustering result of historical disqualification product data in manufacturing process which generated by the Improved-K-means algorithm,a prediction model which is used to detect and recognize the abnormal trend of the quality problems is *** simple and robust alarm-system architecture for predicting incoming faults realizes the transition of quality problems from diagnosis afterward to prevention beforehand *** the end,the alarm model was applied for prediction and avoidance of gear-wheel assembly faults at a gear-plant.

关键词： data mining clustering quality management anomaly detection and recognition

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A SAR sidelobe suppression algorithm based on modified spatially variant apodization

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Science china(Technological Sciences) 2010年第9期53卷 2542-2551页

作者： NI Chong1,2.WANG YanFei1,XU XiangHui1,ZHOU ChangYi1 & CUI PengFei1,2.1 Institute of Electronics,chinese academy of Sciences,{2. 100190,china 2.graduate University of chinese academy of Sciences,beijing 100039,china 1. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China

The existing spatially variant apodizations (SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA (MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A method for synthetic aperture radar (SAR) sidelobe control based on MSVA is presented,which applies MSVA to range compression and azimuth compression to control *** method which is available for any Nyquist sampling rate can both depress the sidelobes effectively and keep the energy of the mainlobe and the resolution of the *** method can reduce sidelobe levels more effectively than classical amplitude weighting while maintaining the image resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression resolution SVA

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Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2. LI Anchun1, HU Ningjing2.3, FU Yongtao1& MA Zhibang4 1. Institute of Oceanology, chinese academy of Sciences, Qingdao 2.6071, {2. 2. graduate school of the chinese academy of Sciences, beijing 100039, {2. 3. Institute of Soil Science, chinese academy of Sciences, Nanjing 2.0008, {2. 4. Institute of Geology and Geophysics, chinese academy of Sciences, beijing 10002., {2. 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. graduate school of the {2. academy of Sciences Beijing 100039 China 3. Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China 4. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

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Compositions of heavy minerals in Northeastern china sandlands and provenance analysis

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Science china Earth Sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2.& DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of Sciences, {2. 10002., china 2.graduate University of chinese academy of Sciences, {2. 100049, china 1. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. graduate University of chinese {2. of Sciences Beijing 100049 China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North china Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern china,garnet,tourmaline

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