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An Intelligent Decision Supp.r. System Generator

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Journal of Systems Engineering and Electronics 1993年第1期4卷 45-52页

作者： Shi Zhenxia and Lu JukangDept. of Computer Science, Shanghai Univ. of Science and Technology, Shanghai 201800, p.r. china Dept. of Computer Science Shanghai Univ. of Science and Technology Shanghai 201800 P.R. China

The focus of this pap.r.is on a new concept framework and an architecture of an intelligent decision supp.r. syetem generator (DSSG). The framework results from a synthesis of two existing frameworks: Spragae and Bonczek, while the architecture is a rooted p.r.ial order network. From our exp.r.ence which comes out of the project of DSSG, we consider that they are keys of further research and development of DSS.

关键词： Decision supp.r. system Decision supp.r. system generator Intelligent decision supp.r. system AI technology Hyp.r.ext technology.

Electron Beam Cladding Surface Modification Technology of Niobium Alloy

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稀有金属材料与工程 2011年第S4期40卷 231-234页

作者： He Jun,Wang Shiwei,Zhang Yonghe Lanzhou Institute of physics,Lanzhou 730000,china Lanzhou Inst phys Lanzhou 730000 Peoples R China

The electron beam cladding (EBC) is a new high-energy surface modification technology developed *** on the analysis of principles and critical technologies in EBC,effect of technological p.r.meters on the microstructure and prop.r.ies of the cladding layer was *** was pointed out that a rational selection of scanning waveform is greatly significant for EBC ***,the progress had achieved and the problems which need to be resolved were introduced.

关键词： electron beam cladding niobium alloy surface modification

Study of spatial distribution of sandy desertification in North china in recent 10 years

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Science china Earth Sciences 2004年第Z1期47卷 78-88页

作者： WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN GuangtingKey Laboratory of Desert and Desertification, Cold and Arid regions Environmental and Engineering research Institute, Chinese Academy of Sciences, Lanzhou 730000, china Dep.r.ment of Environment Engineering, peking University, Beijing 100871, china Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Dep.r.ment of Environment Engineering Peking University Beijing China

Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and p.r. of sub-humid regions in North china. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in china. rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North china. remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57× 104 km2. The area of potential to slightly sandy desertified land is 13.93× 104 km2, moderately land 9.977×104 km2, severely land 7.909 ×104 km2 and very severely land 6.756×104 km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100 km2 ·a-1 in 1976-1988 to 3,600 km2 · a-1 in 1988-2000. The basic status of sandy desertification in North china is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North china can be restored under the conditions of rational land-use ways and intensity.

关键词： sandy desertified land, spatial distribution, remote sensing monitoring, last 10 years, North china.

A STUDY ON DESErTIFICATION OF WEST JILIN prOVINCE BASED ON rEMOTE SENSING AND GIS TECHNIQUES

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Chinese Geographical Science 2002年第1期12卷 73-79页

作者： ZHU Jin hua, LI Jin song(Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, p.r. china) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

'West Jilin province' in this pap.r.means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, Songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping andNong' an which have been suffered from desertification. In west Jilin province there are three sandzones passing through, they are Xiang (Xianghai) -Wu (Ulan Tug) sand zone, Hai-Feng sand zone, andTao'er river right bank sand zone. The desertification area of west Jilin province is 819 100 ha,making up 12. 5% of the total land area. Among desertification types, in Jilin province lightdesertification is the major, then is medium decertification, hevey desertification is the *** to the comp.r.son of the interpretation results of the Landsat images of the 1980s and the1990s by remote sensing and GIS techniques, it can be seen that the desertification area in westJilin province basically didn't change on the whole, only increased 6130 ha, making up 0. 8% of thedesertification area, change scale is less than 1%. Evidently, desertification is controlled mostly,but some areas are continuing deterioration. The desertification process of china can be dividedinto three types according to origin nature, they are sandy steppe desertification, fixed sandarea(sand land) activation and dunes transfer invasion. reasons of desertification of West Jilinprovince are analyzed, they include natural factors (such as material source factors, chimatefactors) and artificial factors (such as destroying grass to reclaim, steppe decreasing greatly,illegally feeling shelter forest stands, constructing reservoir to influence eco-environment etc. ).Some suggestions are put forward as follows: establishing the social project for ecologicalreconstruction of degenerated land; intensifying planning and management of land use, revertingfarmland into forestland or pasture in a planned way. The key desertification control is to dependmainly on policy and management, then control techniques.

关键词： remote sensing (rS) and GIS techniques desertification west jilin province

THE GrOUNDWATEr rESOUrCES AND ITSSUSTAINABLE DEVELOpMENTIN THE SOUTH EDGE OF TArIM BASIN

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Chinese Geographical Science 2001年第1期11卷 57-62页

作者： MA Jin-zhu, LI Ji-jun (College of resources & Environment, Lanzhou University, Lanzhou 730000, p. r. china) College of resources & Environment Lanzhou University Lanzhou P. R. China

There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05 × 109m3/a that is 55.8% of the recharge. Thus the evapotransp.r.tion discharge will reduce 60.4%, while spring water reducing 35.6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85 × 109m3/a with the recharge reducing to 3.1 × 109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In p.r.icular, protection of the glaoier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical imp.r.ant and necessary.

关键词： groundwater resources sustainable development safe yield Tarim Basin

Topological Conditions for Unique Solvability of rLC Op Amp Networks

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Journal of Systems Engineering and Electronics 1996年第4期7卷 47-56页

作者： Yang Jiawei(Beijing Institute of remote Sensing Equipment, Beijing 100854, p.r. china) Beijing Institute of remote Sensing Equipment Beijing 100854 P.R. China

Based on the nullor equivalent model of the ideal op amp, the solvability of rLC op amp networks are discussed and some practical problems are analyzed. Then several necessary and sufficient topological conditions for unique solvability are given and their proofs are shown in *** conditions have great applications in the analysis, synthesis and diagnosis of networks. Finally the solvability of an illustrative network are analyzed as an example.

关键词： Op amp Nullor Topological condition Solvability Tree.

A STrVCTUrE-prESErVING DISCrETIZATION OFNONLINEAr SCHrDINGEr EQUATION

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Journal of Computational Mathematics 1999年第5期17卷 553-560页

作者： Ming-you Huang ru Qu Cheng-chun Gong(Institute of Mathematics, Jilin University, Changchun 130023 p.r. china) 吉林大学数学所吉林长春

This pap.r.studies the geometric structure of nonlinear Schrsdinger equationand from the view-point of preserving structure a kind of fully discrete schemes ispresented for the numerical simulation of this imp.r.ant equation in quantum. Ithas been shown by theoretical analysis and numerical exp.r.ments that such discrete schemes are quite satisfactory in keeping the desirable conservation prop.r.iesand for simulating the long-time behaviour.

关键词： Schrdinger equation Hamiltonian system Discrete schemes Structurepreserving algorithm.

china's Wood Industry after Joining WTO

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Chinese Forestry Science and Technology 2003年第2期2卷 41-46页

作者： CHEN XuheInternational Network for Bamboo and rattan. Beijing 100101. p.r. china

After reviewing the present status and prospects of wood industry in the world, the author suggests that in response to the new situation of economic globalization and china's entry into the WTO, the Chinese wood industry should further develop IT application, optimize and up.r.de industrial structure and raise quality of labor force, blazing a new trail to industrialization featuring high scientific and technological content, good economic return, low resources consumption, little environmental polluti...

关键词： wood industry development WTO

Effects of sunspot cycle length and CO_2 on air temp.r.ture along Qinghai-Xizang railway and air temp.r.ture's trend prediction

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Science china Earth Sciences 2004年第Z1期47卷 131-141页

作者： LI Dongliang, QUO Hui, WANG Wen & WEI LiCold & Arid regions Environmental and Engineering research Institute, Chinese Academy of Science, Lanzhou 730000, china Dep.r.ment of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china Cold & Arid regions Environmental and Engineering research Institute Chinese Academy of Science Lanzhou China Dep.r.ment of Atmospheric Sciences Lanzhou University Lanzhou China

There are well coherences between annual averaged air temp.r.tures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temp.r.ture series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century comp.r.d with the last decade of last century. The mean maximum air temp.r.ture could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temp.r.ture difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.

关键词： Qinghai-Xizang railway, annual mean air temp.r.ture, sunspot cycle length (SCL), atmospheric carbon dioxide concentration (CO2), prediction.