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Study on high and steep slope stability of surface mine based on RFPA-SRM

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Journal of Coal Science & Engineering(China) 2011年第2期17卷 119-123页

作者： WANG Dong CAO Lan-zhu PIAO Chun-de XUE Ying-dong WANG Meng College of Resource and Environment Engineering Liaoning Technical University Fuxin 123000 China School of Mineral Resources and Geoscience China University of Mining ＆ Technology Xuzhou 221008 China Western Open-pit Mine Pingzhuang Energy Corporation Chifeng 024076 China

The instability and failure mechanism of high and steep slopes in surface mines, and the basis for some reasonable landslide prevention measures were provided using the RFPA-SRM. Based on the actual progress of the Pingzhuang Western Surface Mine and based on strength reduction method, the dynamic instability processes of the top high and steep slope was simulated. Also, the landslide mode was determined, the characteristics of the displacement distribution, the deformation, failure, and the stress distribution in the slope were demonstrated, and the stability was calculated. Conclusions can be drawn as follows： the landslide or failure of high and steep slopes on a surface mine is a gradual process, in which the slope undergoes the generation, expansion, and connection of the fractures and the displacement increases until landslide occurs; a small portion of the upper rocks fail due to the tension and the lower rocks fail due to the shear; the potential sliding surface is combined and the essential cause of the landslide is the shear stress concentration.

关键词： strength reduction method high and steep slope slope stability landslide mechanism RFPA-SRM

Live Line Measuring the Parameters of 220 kV Transmission Lines with Mutual Inductance in Hainan Power Grid

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Engineering（科研） 2013年第1期5卷 146-151页

作者： Zhongzhu Xu Zhijian Hu Chuanqi Li Hainan Power Technology Research Institute Hainan Power Grid Corporation Haikou China School of Electrical Engineering Wuhan University Wuhan China

A live line measurement method for the zero sequence parameters of transmission lines with mutual inductance is introduced. The mathematical models of the measurement method are given. Global Positioning System (GPS) is used as the synchronous signal for the measurement carried out at different substations simultaneously. The measurement system and digital simulation results are given. Finally, the live line measurement results of two 220 kV transmission lines with mutual inductance in Hainangrid are given. Results from both simulation and on-site measurement show that the live line measurement method is feasible, and its measurement accuracy can satisfactorily meet the requirements of engineering measurement.

关键词： Transmission lines Zero sequence parameter Mutual inductance Live line measurement GPS

Research on Inter-satellite Link Network Routing Algorithm Based on Multi-objective Optimization

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Research on Inter-satellite Link Network Routing Algorithm B...

An Improved Parasitic Parameter Extraction Method for InP HEMT

第十一届中国卫星导航年会

作者： Sixin Wang Qi Wang Hao Yin Yu Zhou The 6th Research Institute of China Electronics corporation Beijing Institute of Tracking and Telecommunications Technology

In view of the problem that the inter-satellite link network routing planning algorithm adapts to the single business scenario and has poor generalization ability, this paper proposes a multi-objectiv

关键词： inter-satellite link routing planning multi-objective optimization data transmission network connectivity

来源： cnki会议 cnki会议 cnki会议评论

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ZTE Communications 2022年第S1期20卷 1-6页

作者： DUAN Lanyan LU Hongliang QI Junjun ZHANG Yuming ZHANG Yimen ZTE corporation Shenzhen 518057China Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices Xidian UniversityXi’an 710071China

An improved parasitic parameter extraction method for InP high electron mobil-ity transistor(HEMT)is *** parameter extraction is the first step of model parameter extraction and its accuracy has a great impact on the subsequent internal pa-rameter *** is necessary to accurately determine and effectively eliminate the parasitic effect,so as to avoid the error propagation to the internal circuit *** this paper,in order to obtain higher accuracy of parasitic parameters,parasitic parameters are extracted based on traditional analytical method and optimization algorithm to obtain the best parasitic *** validity of the proposed parasitic parameter extraction method is verified with excellent agreement between the measured and modeled S-param-eters up to 40 GHz for InP *** 0.1-40 GHz InP HEMT,the average relative error of the optimization algorithm is about 9%higher than that of the analysis method,which verifies the validity of the parasitic parameter extraction *** extraction of parasit-ic parameters not only provides a foundation for the high-precision extraction of small sig-nal intrinsic parameters of HEMT devices,but also lays a foundation for the high-preci-sion extraction of equivalent circuit model parameters of large signal and noise signals of HEMT devices.

关键词： parasitic parameters open-short test structure parameter extraction HEMT

Usage of Pythagorean Triple Sequence in OSPF

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Communications and Network 2012年第1期4卷 73-82页

作者： Simon Tembo Ken-ichi Yukimatsu Shohei Kamamura Takashi Miyamura Kohei Shiomoto Atsushi Hiramatsu Department of Computer Science and Engineering Akita University Akita City Japan NTT Network Service Systems Laboratories NTT Corporation Tokyo Japan

Shutting down a link for the purposes of a scheduled routine maintenance does cause the forwarding path to change. If these changes are not done in a required order will cause not only transient micro loops but also an overload in some links. Currently, some ISP operators use a graceful link shutdown procedure by first setting up the Interior Gateway Protocol (IGP) link metric to MAX_METRIC -1 and then shutdown the link. In this paper, we present a Pythagorean Triple Metric Sequence as a method to use to shutdown a link during such network operations. Conducting a link shutdown of any desired link for maintenance purpose is a very delicate duty that requires extreme care to prevent transient loops during such topological changes. We thus wish to demonstrate that there exists a Pythagorean Triple Metric Sequence for any given link that can be used to shutdown a link during the routine maintenance by ISPs.

关键词： MAX_METRIC Link Shutdown Pythagorean Triple Metric Sequence Target Metric Forwarding Path Planned Failures

Spatio-Temporal Changes of Soil Salinity in Arid Areas of South Xinjiang Using Electromagnetic Induction

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Journal of Integrative Agriculture 2012年第8期11卷 1365-1376页

作者： LI Xiao-ming YANG Jing-song LIU Mei-xian LIU Guang-ming YU Mei State Key Laboratory of Soil and Sustainable Agriculture/Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R China Engineering Research Center for Land Consolidation Shaanxi Provinee/Shaanxi Estate Development Service Corporation Xi'an 710075 P.R.China Water Conservancy Bureau of Yuhuatai Nanjing 210012 P.R.China

The aim of this paper was to research the spatio-temporal changes in total soluble salt content （TS） in a typical arid region of South Xinjiang, China, where the climate is arid and soil salinization happens easily. The total soluble salt content was interpreted by measurements made in the horizontal mode with EM38 and EM31. The electromagnetic induction （EM） surveys were made three times with the apparent soil electrical conductivity （ECa） measurements taken at 3 873 locations in Nov. 2008, 4 807 locations in Apr. 2009 and 6 324 locations in Nov. 2009, respectively. For interpreting the ECa measurements into total soluble salt content, calibtion sites were needed for EM survey of each time, e.g., 66 sites were selected in Nov. 2008 to measure ECa, and soils-core samples were taken by different depth layers of 0-10, 10-20 and 20-40 cm at the same time. On every time duplicate samples were taken at five sites to allevaite the local-scale variability, and soil temperatures in different layers through the profiles were also measured. Factors including TS, pH, water content, bulk density were analyzed by lab experiments. ECa calibration equations were obtained by linear regression analysis, which indicated that soil salinity was one primary concern to ECa with a determination coefficient of 0.792 in 0-10 cm layer, 0.711 in 10-20 cm layer and 0.544 in 20-40 cm layer, respectively. The maps of spatial distribution were predicted by Kriging interpolation, which showed that the high soil salinity was located near the drainage canal, which validated the trend effect caused by the irrigation canal and the drainage canal. And by comparing the soil salinity in different layers, the soluble salt accumulated to the top soil surface only in the area where the soil salinization was serious, and in the other areas, the soil salinity trended to increase from the top soil surface to 40 cm depth. Temporal changes showed that the soil salinity in November was higher than that in April,

关键词： spatio-temporal changes soil salinity South Xinjiang electromagnetic induction (EM) Kriging

Temperature sensitivity of soil organic matter decomposition varies with biochar application and soil type

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Pedosphere 2020年第3期30卷 336-342页

作者： Tatiana FRITTL Luiza CANISARES Edvaldo SAGRILO Klaus BUTTERBACH-BAHL Michael DANNENMANN Carlos EPCERRI Soil Science Department Luiz de Queiroz College of AgricultureUniversity of São PauloPiracicabaSão Paulo 13418-900(Brazil Karlsruhe Institute of Technology Institute of Meteorology and Climate ResearchAtmospheric Environmental Research(IMK-IFU)Garmisch-Partenkirchen 82467Germany Brazilian Agricultural Research corporation(Embrapa Meio-Norte) TeresinaPiauí70770-901Brazil

Biochar application has the potential to improve soil fertility and increase soil carbon stock, especially in tropical regions. Information on the temperature sensitivity of carbon dioxide(CO2) evolution from biochar-amended soils at very high temperatures, as observed for tropical surface soils, is limited but urgently needed for the development of region-specific biochar management targeted to optimize biochar effects on soil functions. Here, we investigated the temperature sensitivity of soil respiration to the addition of different rates of Miscanthus biochar(0, 6.25, 12.5, and 25 Mg ha-1) in two types of soils with contrasting textures. Biochar-amended soil treatments and their controls were incubated at constant temperatures of 20, 30, and 40℃. Overall, our results show that: i) considering data from all treatments and temperatures, the addition of biochar decreased soil CO2 emissions when compared to untreated soils;ii) CO2 emissions from biochar-amended soils had a higher temperature sensitivity than those from biochar-free soils;iii) the temperature sensitivity of soil respiration in sandy soils was higher than that in clay soils;and iv) for clay soils, relative increases in soil CO2 emissions from biochar-amended soils were higher when the temperature increased from 30 to 40℃, while for sandy soils, the highest temperature responses of soil respiration were observed when increasing the temperature from 20 to 30℃. Together, these findings suggest a significantly reduced potential to increase soil organic carbon stocks when Miscanthus biochar is applied to tropical soils at high surface temperatures, which could be counteracted by the soil-and weather-specific timing of biochar application.

关键词： carbon dioxide clay soil greenhouse gas emission Miscanthus biochar sandy soil tropical soil

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使用回流填充胶的FC组装

世界产品与技术 2002年第2期 60-65页

作者： Pericles A.Kondos Peter Borgesen 康常 Ph.D.Universal Instruments corporation

引言传统的共晶焊料filp chip组装,在芯片贴放前有两种施加助焊剂的方法:一种是施加在基板上,另一种是将芯片焊凸浸在一层助焊剂薄膜中。后一种方法提供更好的“连接力”(“Tack”),因此回流前芯片偏移的可能较小,另一方面,贴片前施加... 详细信息

引言传统的共晶焊料filp chip组装,在芯片贴放前有两种施加助焊剂的方法:一种是施加在基板上,另一种是将芯片焊凸浸在一层助焊剂薄膜中。后一种方法提供更好的“连接力”(“Tack”),因此回流前芯片偏移的可能较小,另一方面,贴片前施加助焊剂可能有助于提高产能。这两种方法在回流焊接时都需要有氮气的环境。如图1,回流后,必须用适合的填充胶对硅片进行底部填充,在毛细作用下填充胶会流进芯片底部。免清洗助焊剂的残留物既影响底部填充时的润湿及流动。

关键词：回流填充胶 FC组装微电子

Connotation and research strategy of the whole petroleum system

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Petroleum Exploration and Development 2024年第6期51卷 1386-1401页

作者： SONG Yan JIA Chengzao JIANG Lin MA Xingzhi SHAO Xindi PetroChina Research Institute of Petroleum Exploration & Development China National Petroleum corporation Unconventional Petroleum Research Institute China University of Petroleum (Beijing)

Traditional petroleum system theories emphasize the restoration of the accumulation process from “source” to “trap”. The main oil and gas resources in the concept are conventional oil and gas, lacking the concept and research of unconventional oil and gas enrichment mechanism. The whole petroleum system is developed from the traditional petroleum system. Combined with unconventional oil and gas exploration practices and discoveries such as shale oil and gas, the whole petroleum system adds the research content of unconventional oil and gas. Although the study of the whole petroleum system is still in three aspects: geological elements, dynamic evolution and oil and gas distribution, its research ideas and research contents are very different, including the following three aspects.(1) In terms of geological elements, the traditional petroleum system studies the characteristics of source rocks and hydrocarbon generation evolution, and the reservoir properties, traps, migration and preservation conditions of conventional oil and gas. On the basis of the above research, the whole petroleum system has increased the quantitative evaluation of retained hydrocarbons, unconventional reservoir characterization, source reservoir configuration and other research contents.(2) In terms of dynamic evolution, the petroleum system studies the matching between the evolution of conventional oil and gas source rocks and the formation period of traps, while the whole petroleum system has increased the research content of the matching of unconventional reservoir densification and oil and gas charging, and the later transformation of unconventional oil and gas reservoirs.(3) In terms of oil and gas distribution, the petroleum system takes buoyancy-drived accumulation mechanism as the core to study the migration, accumulation and distribution of conventional oil and gas. The whole petroleum system adds unconventional oil and gas self-sealing accumulation mechanism and conventional-unconven

关键词： whole petroleum system conventional-unconventional oil and gas research strategy geological elements dynamic evolution distribution sequence