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CSEE Journal of Power and Energy Systems 2024年第2期10卷 468-480页

作者： Hongjie He Ning Zhang chongqing Kang Song Ci Fei Teng Goran Strbac State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Department of Electrical and Electronic Engineering Imperial College LondonSW72BULondonU.K

The high renewable penetrated power system has severe frequency regulation *** resources can provide frequency regulation services but are limited by com-munication time *** paper proposes a communication resources allocation model to reduce communication time delay in frequency regulation *** device resources and wireless spectrum resources are allocated to distributed resources when they participate in frequency *** reveal impact of communication resources allocation on time delay reduction and frequency regulation ***,we study communication resources allocation solution in high renewable energy penetrated power *** provide a case study based on the HRP-38 *** show communication time delay decreases distributed resources'ability to provide frequency regulation *** the other hand,allocating more communication resources to distributed resources'communica-tion services improves their frequency regulation *** power systems with renewable energy penetration above 70%,required communications resources are about five times as many as 30%renewable energy penetrated power systems to keep frequency performance the *** Terms-Communication resources allocation,commun-ication time delay,distributed resource,frequency regulation,high renewable energy penetrated power system.

关键词： Communication resources allocation communication time delay distributed resource frequency regulation high renewable energy penetrated power system

Air flow exploration of abrasive feed tube

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Acta Mechanica Sinica 2009年第6期25卷 761-768页

作者： Shijin Zhang Xiaohong Li Yilei Gu college of resources and {2. science,chongqing university, 400044 chongqing, China college of resources and {2. science Chongqing University 400044 Chongqing China

An abrasive water-jet cutting process is one in which water pressure is raised to a very high pressure and forced through a very small orifice to form a very thin high speed jet beam. This thin jet beam is then directed through a chamber and then fed into a secondary nozzle, or mixing tube. During this process, a vacuum is generated in the cham- ber, and garnet abrasives and air are pulled into the chamber, through an abrasive feed tube, and mixes with this high speed stream of water. Because of the restrictions introduced by the abrasive feed tube geometry, a vacuum gradient is generated along the tube. Although this phenomenon has been recog- nized and utilized as a way to monitor nozzle condition and abrasive flowing conditions, yet, until now, conditions inside the abrasive feed line have not been completely understood. A possible reason is that conditions inside the abrasive feed line are complicated. Not only compressible flow but also multi- phase, multi-component flow has been involved in inside of abrasive feed tube. This paper explored various aspects of the vacuum creation process in both the mixing chamber and the abrasive feed tube. Based on an experimental exploration, an analytical framework is presented to allow theoretical calculations of vacuum conditions in the abrasive feed tube.

关键词： Abrasive feed tube- Water jet cutting. Vacuum gradient

Scenario simulation and forecast of land use/cover in northern China

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 college of Geographical science, {2. Normal university, {2. 400047, China 2.college of resources and environmental science, chongqing university, chongqing 400044, China 3 college of resources science & Technology, Beijing Normal university, Beijing 100875, China college of Geographical science Chongqing Normal University Chongqing 400047 China college of resources and {2. science Chongqing University Chongqing 400044 China college of resources {2. & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern China in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern China.

关键词：土地利用中国北方细胞自动机系统动力学

Combining Ridge with No-Tillage in Lowland Rice-Based Cropping System: Long-Term Effect on Soil and Rice Yield

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Pedosphere 2009年第4期19卷 515-522页

作者： JIANG Xian-Jun2.and XIE De-Ti college of resources and Environment, Southwest {2., 2.6 Tiansheng Road, Beibei, chongqing 400716 (China) [a]college of resources and Environment Southwest University 216 Tiansheng Road Beibei Chongqing 400716 (China)

A tillage method of combining ridge with no-tillage (RNT) was employed in lowland rice-based cropping system to study the long-term effects of RNT on soil profile pattern, soil water stable aggregate distribution, nutrients stratification and yields of rice and post-rice crops. After flooded paddy field (FPF) was practiced with RNT for a long time, soil profile changed from G to A-P-G, and horizon G was shifted to a deeper position in the profile. Also the proportion of macroaggregate (> 2.mm) increased, whereas the proportion of silt and clay (2.03 and 2.06 when serious drought occurred. RNT was proven to be a better tillage method for lowland rice-based cropping system.

关键词： aggregate-size distribution conservative tillage flooded paddy field soil profile pattern

Heavy Metal Runoff in Relation to Soil Characteristics

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Pedosphere 2001年第2期11卷 137-142页

作者： ZHAO XIULAN, QING CHANGLE and WEI SHIQIANG college Of resources and {2. science, Southwest Agricultural university, chongqing 400716 (china) 西南农业大学重庆 400716

Cu, Zn, Pb and Hg runoff from yellow limestone soil and purple soils and the relationships between the mobility of the heavy metals and the soil characteristics were studied in laboratory using a rainfall simulator. The results showed that the concentrations of soluble Zn in surface runoff were significantly negatively correlated with the contents of 2.mm particles and CEC of the soils, indicating that Zn was mostly adsorbed by clays in the soils. The contents of Cu and Hg in surface runoff were positively related to their contents in the soils. The amounts of Cu, Zn, Pb and Hg removed by surface runoff were influenced by the amounts of soil and water losses and their contents in the soils, and were closely related to the contents of soil particles 1-0.02.mm in size.

关键词： heavy metal mobility soil characteristics surface runoff

Research of E-Commerce System Based on EJB for Manufacture Enterprise

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厦门大学学报（自然科学版） 2002年第S1期41卷 286-287页

作者： WEI Zhao-wen 1, LI Yong 2. SU Yi-dan 1 (1. Computer & Information Engineering college, Guangxi university, N anning 530004, China 2. Business Administration college, chongqing university, chongqing 400044, Chi na)

During the popular and development in Internet, mor e and more EC systems are running on Internet. Manufacture enterprise establishes EC system, integrates the systems between enterprises replace the traditional MI S system. The manufacture enterprise will face some difficulties when it begins to establish EC system. In order to solve the difficulties, the EC system not on ly includes the functions which in general EC system, but also integrates ERP sy stem, manages the enterprise from three aspects: relationship between manufactur er and customers, enterprise resources, and supplying chain, and gives the manuf acturer more intelligent information. As the departments of enterprise exchange data very frequently, connect the sellers and suppliers by using Internet, the t raditional C/S architecture isn’t satisfied by present needs. It is the only wa y that uses Multi-tier architecture. EJB (Enterprise Java Bean) is a Multi-tier distributed architecture designed by SUN company. The Enterprise JavaBeans architecture is a component architecture for the development and development of component-based distributed business app lications. Applications written using the Enterprise JavaBeans architecture are scalable, transactional, and multi-user secure. These applications may be writt en once, and then deployed on any server platform that supports the Enterprise J avaBeans specification. There are many superiorities using EJB when design compu ter system. The EC System for Manufacture Enterprise is based on EJB architecture. We define four EJB containers, namely, CRM component, POM component, Knowledge Management component and ERP component. CRM EJBs take the form of managing the customer- supplier relationship, reducing the number of contracts the manufacturer must ma ke with the end customers. POM EJBs take the form of order processing activities . These order taking, order fulfillment, and managing the logistics and transpor tation involved in the physical movement of the

关键词： E-Commerce EJB CRM ERP

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3 & YE Xianren2.1. resources and environmental School, Lanzhou {2., Lanzhou 730000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, China 3. college of resources science & Technology, Beijing Normal {2., Beijing 100875, China 1. resources and environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of resources {2. & Technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3He/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3He from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Edaphic factors determining variation of two ecotypes of Leymus chinensis in North China

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Progress in Natural science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2.*(1. MOE Key Laboratory of environmental Change and Natural Disasters, college of {2. science and Technology, Beijing Normal university, Beijing 100875, China 2. Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland science, Northeast Normal university, Changchun 13002., China) [a]MOE Key Laboratory of environmental Change and Natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin

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science China Earth sciences 2006年第12期49卷 1299-1310页

作者： SONG Xianfang1, LIU Xiangchao1, 2. XIA Jun1, YU Jingjie1 & TANG Changyuan1, 3 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical sciences and Natural Re- sources Research, Chinese Academy of sciences, Beijing 100101, China 2. {2. of River and Ocean, chongqing Jiaotong university, chongqing 400074, China 3. Chiba university, Chiba 2.3-852., Japan 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institut of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. college of River and Ocean Chongqing Jiaotong University Chongqing 400074 China 3. Chiba university Chiba 263-8522 Japan

The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, environmental isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, Beijing. The field surveying and sampling for spring, river and well water were finished in 2.02.and 2.03. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly.

关键词： environmental isotope,hydrochemistry,surface water,groundwater,interaction.

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2. LIU Chang-hua2. ZHANG He-bing2.1. college of resources {2. and Technology, Beijing Normal university, Beijing 100875, China 2. School of Surveying and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, China [a] college of resources {2. and Technology Beijing Normal University Beijing 100875 China [b] School of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine