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Comparison of some Methods on Prediction of Activity Interaction Coefficient

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 13-15页

作者： Changxiang Xiang Ningxin Zhang (Applied science school, university of science and Technology beijing,{3.) Applied science school University of Science and Technology Beijing Beijing 100083 China

Based on Miedema's semiempirical formation enthalpy model for binary alloys, free volume theory and ageneral solution model, a new model for prediction of activity interaction coefficient ε is proposed. The calculatedresults are better in agreement with the experimental values than the two previous models. The related theories andmodels are discussed according to the degree of agreement with experimental values.

关键词： Miedema's semiempirical formation enthalpy model activity interaction coefficient free volume theory similarity coefficient

Equilibrium Precipitation of Niobium Carbonitride in Austenite

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 119-122页

作者： Fuming Wang Wenchao Li(Applied science school, university of science and Technology beijing,{3.) Applied science school University of Science and Technology Beijing Beijing 100083 China

The equilibrium between niobium carbonitride and austenite has been studied. Experimentally, X-raydiffaction technique was adopted to verify that the precipitates have the same composition and structure. Theoretical-ly, Hillert and staffansson's regular model about stoichimetric phase was used to describe the thermodynamic proper-ties of multi-component precipitate. Calculated results agree well with experimental values from literatures.

关键词： equilibrium niobium precipitate, austenite

Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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science china earth sciences 2005年第7期48卷 939-949页

作者： sHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3.& WANG Lili1 1. Institute of geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, {3. 2. National Climate Center, beijing 100081, {3. 3. beijing Normal university, beijing 100875, {3. Institute of geographic sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China beijing Normal university Beijing 100875 China

Using seven well-replicated Qilian juniper (sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—163. and 193.—2001, whereas dry intervals in 1429—1519 and 163.—1741. In ad- dition, the magnitude in precipitation variation was lower before 143. with about 15 mm, but it increased to 3. mm during the period of 143. to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 2.st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

Optimization of Fractal Iterated Function system(IFs) with Probability and Fractal Image Generation

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Journal of university of science and Technology beijing 2001年第2期8卷 152-156页

作者： Berthe Kya, Yang Yang (Information Engineering school, university of science and Technology beijing,{3.) Univ sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

There are several methods for rendering fractal images based on IFs (Iterated Function system) in computer graphic; but one concern of the computer graphic community has been the efficiency rendering algorithms. The invariant measures arising from IFsP (Iterate Function system with Probability) using the probabilistic algorithm are also known as chaos games. The role of these probabilities to generate the image of the attractor has been investigated using a multi-fractal analysis. The conventional choice of probability associated with each set /s/ to generate the attractor in least time possible is introduced, then a new method based on the self similarity and multi-fractal analysis is presented. The efficiency of the new method has been proved over the conventional method.

关键词： optimization of fractal IFs compression IFsP multi-fractal analysis

sHRIMP dating of the Bangong Lake ssZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet

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Chinese science Bulletin 2007年第7期52卷 936-941页

作者： sHI RenDeng1,2 1 school of earth and space sciences, university of science and Technology of {3., Hefei 23.026, {3. 2 Institute of geology, Chinese Academy of geological sciences, beijing 10003., {3. (email: shird@***) school of earth and space sciences University of Science and Technology ofChina Hefei 230026 China

The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with ssZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The sHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MsWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.

关键词：西藏班公湖怒江缝合带古海洋闭合时期 ssZ型蛇绿岩 sHRIMP 测年

sea level variations in the south china sea inferred from satellite gravity,altimetry,and oceanographic data

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science china earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2,ZHONG Min 1,3.& XU HouZe 1,3.1 state Key Laboratory of geodesy and earth’s Dynamics,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.Institute of geophysics,Huazhong university of science and Technology,Wuhan 43.074,china 1. state Key Laboratory of geodesy and earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

sea level variations(sLVs) can be divided into two major components:the steric sLV and the mass-induced *** two components of sLV in the south china sea(sCs) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced sLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced sLV in the sCs with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3.cm estimated from the steric-corrected *** the inter-annual timescales,the mean sLV in the sCs shows a large oscillation,which is mainly caused by the steric *** trend of mean sLV inferred from altimetry in the sCs is 5.5±0.7 mm/yr for the period of 1993.2009,which is significantly higher than the global sea level rise rate of 3.3.0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced sLV detected from GRACE that indicates the water exchange between the sCs and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the south china sea sea level variation

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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science china earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, {3. 2. Graduate school of the Chinese Academy of sciences, beijing 10003., {3. 3. College of resources and Environment, southwest Agricultural university, Chongqing 400716, {3. 4. The Ministry of science and Technology, P. C. {3., beijing 100862, {3. 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 610041, {3. 1. Institute of geographic sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. College of resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. so the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIs, Rs.

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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science china(Technological sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2, sHEN Zhenyao1 & LI Jianqiang3.1. school of Environment, state Key Laboratory of Water Environment simulation, beijing Normal Univer- sity, beijing 100875, {3. 2. school of Environment, Key Laboratory for Water and sediment sciences of Ministry of Education, beijing Normal university, beijing 100875, {3. 3. Water resources and Hydropower Planning and Design General Institute, MWR, beijing 100011, {3. beijing Normal Univ Sch Environm State Key Lab Water Environm Simulat Beijing 100875 Peoples R China beijing Normal Univ Sch Environm Key Lab Water & Sediment Sci Minist Educ Beijing 100875 Peoples R China MWR Water Resources & Hydropower Planning & Design Ge Beijing 100011 Peoples R China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective Decision-Making (IIMMODM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMODM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMODM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMODM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.

A new method for spatio-temporal prediction of rainfall-induced landslide

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science china earth sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2, YANG Zhifa2, sHANG Yanjun2, ZHOU shenghua1 & YIN Juntao3.1. china Non-ferrous Metals Resource geological survey, beijing 100012, china 2. Institute of geology and geophysics, Chinese Academy of sciences, Key Laboratory of Engineering geomechanics, beijing 100029, china 3. school of geoscience & Environmental Engineering, Central south university, Changsha 410083. china 1. china Non-ferrous Metals Resource geological survey Beijing 100012 China 2. Institute of geology and geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing 100029 China 3. school of geoscience & Environmental Engineering Central South University Changsha 410083 China

geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4 grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.