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含铜氧化型金矿石电集法提金工艺实验研究 被引量:1
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作者 刘勤安 张红军 +3 位作者 张参辉 刘振超 陈丽娜 王宏猷 《长春工程学院学报(自然科学版)》 2015年第2期105-108,共4页
常规提金工艺对含铜氧化型金矿石氰化处理不仅容易造成资源浪费,更会造成严重环境污染。为解决这些问题,通过研究采取在常规堆浸基础上,浸出液用电集法回收金银的工艺流程,克服了常规提金工艺处理该类型金矿石经济效益差和对环境污染大... 常规提金工艺对含铜氧化型金矿石氰化处理不仅容易造成资源浪费,更会造成严重环境污染。为解决这些问题,通过研究采取在常规堆浸基础上,浸出液用电集法回收金银的工艺流程,克服了常规提金工艺处理该类型金矿石经济效益差和对环境污染大等问题,取得了较高的金、银、铜综合回收比例。本文不仅详细阐述了该工艺工作流程、原理和注意事项,而且将该提金工艺实验推广应用于其他氧化型金矿石的金银提取。 展开更多
关键词 金矿 含铜氧化型金矿石 提金工艺 电集法
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电集法技术的有关问题有展望
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作者 藤岛英胜 梁运章 《静电》 1995年第1期15-20,共6页
关键词 除尘 煤炭 飞灰 电集法技术
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电捕集法消除空气中的氚 被引量:1
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作者 王兰新 但贵萍 +1 位作者 张子骞 苑国琪 《四川环境》 北大核心 1995年第2期21-25,共5页
本文研究了一种净化空气中氚的新方法,我们用四水合磷酸铀酰氢(Hup)作消氚剂,在外加直流电场的作用下,直接消除潮湿空气中的氚。用不同面积的消氚圆片,在静态、常温、常压下,外加4~7伏直流电场,50小时左右,可使2.2... 本文研究了一种净化空气中氚的新方法,我们用四水合磷酸铀酰氢(Hup)作消氚剂,在外加直流电场的作用下,直接消除潮湿空气中的氚。用不同面积的消氚圆片,在静态、常温、常压下,外加4~7伏直流电场,50小时左右,可使2.2升含氚空气中氚的净化率超过90%。空气中氚含量为0.2~10ppm,含水量为3000~12000ppm。我们用液闪测量了消氚后消氚圆片中氚的含量,其结只与用电离室所测的结果一致。 展开更多
关键词 消氚剂 磷酸铀酰氢 净化
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A seafloor electromagnetic receiver for marine magnetotellurics and marine controlled-source electromagnetic sounding 被引量:7
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作者 陈凯 魏文博 +2 位作者 邓明 伍忠良 余刚 《Applied Geophysics》 SCIE CSCD 2015年第3期317-326,466,共11页
In planning and executing marine controlled-source electromagnetic methods, seafloor electromagnetic receivers must overcome the problems of noise, clock drift, and power consumption. To design a receiver that perform... In planning and executing marine controlled-source electromagnetic methods, seafloor electromagnetic receivers must overcome the problems of noise, clock drift, and power consumption. To design a receiver that performs well and overcomes the abovementioned problems, we performed forward modeling of the E-field abnormal response and established the receiver's characteristics. We describe the design optimization and the properties of each component, that is, low-noise induction coil sensor, low-noise Ag/AgCI electrode, low-noise chopper amplifier, digital temperature-compensated crystal oscillator module, acoustic telemetry modem, and burn wire system. Finally, we discuss the results of onshore and offshore field tests to show the effectiveness of the developed seafloor electromagnetic receiver and its performance: typical E-field noise of 0.12 nV/m/rt(Hz) at 0.5 Hz, dynamic range higher than 120 dB, clock drift lower than 1 ms/day, and continuous operation of at least 21 days. 展开更多
关键词 MCSEM seafloor EM receiver seafioor electric field sensor chopper amplifier acoustic telemetry modem
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A Fast and Efficient Global Router for Congestion Optimization 被引量:2
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作者 许静宇 鲍海云 +3 位作者 洪先龙 蔡懿慈 经彤 顾钧 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第2期136-142,共7页
An efficient parallel global router using random optimization that is independent of net ordering is proposed.Parallel approaches are described and strategies guaranteeing the routing quality are discussed.The wire le... An efficient parallel global router using random optimization that is independent of net ordering is proposed.Parallel approaches are described and strategies guaranteeing the routing quality are discussed.The wire length model is implemented on multiprocessor,which enables the algorithm to approach feasibility of large scale problems.Timing driven model on multiprocessor and wire length model on distributed processors are also presented.The parallel algorithm greatly reduces the run time of routing.The experimental results show good speedups with no degradation of the routing quality. 展开更多
关键词 global routing congestion optimizing global routing graph (GRG) parallel algorithm
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The Nucleosides Contents and Their Variation in Natural Cordyceps sinensis and Cultured Cordyceps Mycelia 被引量:15
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作者 李绍平 李萍 +3 位作者 季晖 朱荃 董婷霞 詹华强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期175-179,共5页
Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleos... Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleosides were determined by using high performance capillary electrophoresis (HPCE). Beckman P/ACE System 5010 apparatus equipped with a UV detector and a Beckman untreated fused-silica capillary (57 cm 75 mm, 50 cm effective length) was used. Before sample injection, the capillary was rinsed with 1 molL-1 sodium hydroxide solution and running buffer for 5 min, respectively. A voltage of 20 kV was applied for the separation. Pressure injection was 586 kPa for 6 seconds, and the wavelength of detector was 254 nm. The running time was 20 min at 20 oC. The effect of humidity and heat on the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia was observed for 1, 3, 5 and 10 days at temperature 40 oC, and relative humidity 75%. Results: The content of nucleosides from natural Cordyceps sinensis was higher than that from cultured Cordyceps mycelia. But the contents of nucleosides from freshly collected natural Cordyceps sinensis were very low, even below the limit of quantitation. The contents of nucleosides from natural Cordyceps sinensis were significantly increased by humidity and heat, but this phenomenon was not observed in cultured Cordyceps mycelia. Conclusion: There are differences between the nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia. The nucleosides in natural Cordyceps sinensis may be derived from the degradation of nucleic acids. This implies that adenosine being used for the quality control of natural Cordyceps sinensis may have to be reconsidered. 展开更多
关键词 CORDYCEPS NUCLEOSIDES ADENOSINE GUANOSINE URIDINE
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MARS:A General Multilayer Area Router 被引量:1
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作者 马琪 严晓浪 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第4期516-519,共4页
Based on a ripped-up and rerouted methodology,a multilayer area detailed router is presented by using simulated evolution technique.A modified maze algorithm is also performed for the single net.
关键词 multilayer area detailed router simulated evolution modified maze algorithm
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An Asynchronous Implementation of Add-Compare-Select Processor for Communication Systems
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作者 赵冰 仇玉林 +1 位作者 吕铁良 黑勇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第5期886-892,共7页
A novel asynchronous ACS(add-compare-select) processor for Viterbi decoder is described.It is controlled by local handshake signals instead of the globe clock.The circuits of asynchronous adder unit,asynchronous compa... A novel asynchronous ACS(add-compare-select) processor for Viterbi decoder is described.It is controlled by local handshake signals instead of the globe clock.The circuits of asynchronous adder unit,asynchronous comparator unit,and asynchronous selector unit are proposed.A full-custom design of asynchronous 4-bit ACS processor is fabricated in CSMC-HJ 0.6μm CMOS 2P2M mixed-mode process.At a supply voltage of 5V,when it operates at 20MHz,the power consumption is 75.5mW.The processor has no dynamic power consumption when it awaits an opportunity in sleep mode.The results of performance test of asynchronous 4-bit ACS processor show that the average case response time 19.18ns is only 82% of the worst-case response time 23.37ns.Compared with the synchronous 4-bit ACS processor in power consumption and performance by simulation,it reveals that the asynchronous ACS processor has some advantages than the synchronous one. 展开更多
关键词 asynchronous circuits Viterbi decoder ACS response time
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A Chip Level Thermal Analysis Algorithm Using Boundary Element Method
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作者 崔铭栋 赵文庆 唐璞山 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第5期558-564,共7页
With the scale of integration and operation speed of modern ICs increasing,a series of thermo-related problems arise.Hot spots,which are due to the uneven distribution of heat,invalidate some functions of the chip.An ... With the scale of integration and operation speed of modern ICs increasing,a series of thermo-related problems arise.Hot spots,which are due to the uneven distribution of heat,invalidate some functions of the chip.An algorithm is presented to calculate the profile.With the boundary element method,3D problems are converted into 2D ones,so the temperatures of both the chip surface and inner points can be calculated quickly.This algorithm can be used to evaluate the thermal quality of a definite chip. 展开更多
关键词 VLSI thermal analysis
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A Compact Low Energy Electron Microscope for Surface Analysis
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作者 张冠华 孙巨龙 +3 位作者 金艳玲 臧侃 郭方准 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第4期369-373,J0001,共6页
The description and function characterization of a flange-on type low energy electron mi- croscope are given. In this microscope a magnetic beam separator with 10° deflection angle is used in order to facilitate ... The description and function characterization of a flange-on type low energy electron mi- croscope are given. In this microscope a magnetic beam separator with 10° deflection angle is used in order to facilitate compacting the instrument on a single 10 in. flange. Mean- while some correcting elements in the electron optical system are simplified to reduce the complexities of construction and operation. The sample is set close to ground potential, so that all the electrostatic lenses are easily to float at high voltages. The performance of the microscope in typical low energy electron microscopy, low energy electron diffraction and photoemission electron microscopy modes is demonstrated through several experiments. A lateral resolution of 51 nm is estimated for low energy electron microscopy imaging. With femtosecond laser as light source, the consequent nonlinear photoemission makes this micro-scope also suitable for the observation of optical near field phenomena and a lateral resolution of 110 nm is obtained. 展开更多
关键词 Low energy electron microscopy Flange-on Femtosecond laser Lateral reso-lution Small deflection angle
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Fabrication of LaAlO3 film by sol-gel process with corresponding inorganic 被引量:1
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作者 殷明志 汪敏强 姚熹 《Journal of Zhejiang University Science》 EI CSCD 2004年第6期696-698,共3页
Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and aluminum acetate glacial acetic acid solut... Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3 (AcAc)x, which were hydrolyzed into La(AcAc)3 (OH)x by ?x ?x adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3 (OH)x, polymerizing and combining with MCL, ?x formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650?750 °C/30 min. The mor- phologies and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and the dissipation factors were estimated to be 23?26 and 2.1×10?4 ? 2.4×10?4 respectively. 展开更多
关键词 Sol-gel method LaAlO3 film Dielectric constant
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Genetic Algorithm-Based Redundancy Optimization Method for Smart Grid Communication Network 被引量:4
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作者 SHI Yue QIU Xuesong GUO Shaoyong 《China Communications》 SCIE CSCD 2015年第8期73-84,共12页
This paper proposes a redundancy optimization method for smart grid Advanced Metering Infrastructure(AMI) to realize economy and reliability targets.AMI is a crucial part of the smart grid to measure,collect,and analy... This paper proposes a redundancy optimization method for smart grid Advanced Metering Infrastructure(AMI) to realize economy and reliability targets.AMI is a crucial part of the smart grid to measure,collect,and analyze data about energy usage and power quality from customer premises.From the communication perspective,the AMI consists of smart meters,Home Area Network(HAN) gateways and data concentrators;in particular,the redundancy optimization problem focus on deciding which data concentrator needs redundancy.In order to solve the problem,we first develop a quantitative analysis model for the network economic loss caused by the data concentrator failures.Then,we establish a complete redundancy optimization model,which comprehensively consider the factors of reliability and economy.Finally,an advanced redundancy deployment method based on genetic algorithm(GA) is developed to solve the proposed problem.The simulation results testify that the proposed redundancy optimization method is capable to build a reliable and economic smart grid communication network. 展开更多
关键词 smart grid advanced metering infrastructure redundancy optimization dataconcentrator genetic algorithm
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A scalable and low power VLIW DSP core for embedded system design 被引量:1
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作者 Sheraz Anjum 陈杰 +4 位作者 韩亮 林川 张晓潇 苏叶华 程亚奇 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期172-175,共4页
Aims to provide the block architecture of CoStar3400 DSP that is a high performance, low power and scalable VLIW DSP core, it efficiently deployed a variable-length execution set (VLES) execution model which utilizes ... Aims to provide the block architecture of CoStar3400 DSP that is a high performance, low power and scalable VLIW DSP core, it efficiently deployed a variable-length execution set (VLES) execution model which utilizes the maximum parallelism by allowing multiple address generations and data arithmetic logic units to execute multiple instructions in a single clock cycle. The scalability was provided mainly in using more or less number of functional units according to the intended application. Low power support was added by careful architectural design techniques such as fine-grain clock gating and activation of only the required number of control signals at each stage of the pipeline. The said features of the core make it a suitable candidate for many SoC configurations, especially for compute intensive applications such as wire-line and wireless communications, including infrastructure and subscriber communications. The embedded system designers can efficiently use the scalability and VLIW features of the core by scaling the number of execution units according to specific needs of the application to effectively reduce the power consumption, chip area and time to market the intended final product. 展开更多
关键词 Very Long Instruction Word (VLIW) low Dower DSP compute intensive system on chip (SoC)
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A natural language user interface for fuzzy scope queries 被引量:1
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作者 黄艳 俞宏峰 +1 位作者 耿卫东 潘支鹤 《Journal of Zhejiang University Science》 CSCD 2003年第2期152-161,共10页
This paper presents a two-agent framework to build a natural langua g e query interface for IC information system, focusing more on scope queries in a single English sentence. The first agent, parsing agent, syntact... This paper presents a two-agent framework to build a natural langua g e query interface for IC information system, focusing more on scope queries in a single English sentence. The first agent, parsing agent, syntactically p rocesses and semantically interprets natural language sentence to construct a fu zzy structured query language (SQL) statement. The second agent, defuzzif ying agent, defuzzifies the imprecise part of the fuzzy SQL statement into its e quivalent executable precise SQL statement based on fuzzy rules. The first agent can also actively ask the user some necessary questions when it manages to disa mbiguate the vague retrieval requirements. The adaptive defuzzification approach employed in the defuzzifying agent is discussed in detail. A prototype interface has been implemented to demonstrate the effectiveness. 展开更多
关键词 Integrated circuit information system Natural langua ge user interface GRAMMAR Fuzzy rule Matching degree
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InP-Based RTD/HEMT Monolithic Integration
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作者 齐海涛 郭维廉 +2 位作者 李亚丽 张雄文 李效白 《Transactions of Tianjin University》 EI CAS 2010年第4期267-269,共3页
Monolithic integration of resonant tunneling diodes (RTDs) and high electron mobility transistors (HEMTs) is an important development direction of ultra-high speed integrated circuit. A kind of top-RTD and bottom-HEMT... Monolithic integration of resonant tunneling diodes (RTDs) and high electron mobility transistors (HEMTs) is an important development direction of ultra-high speed integrated circuit. A kind of top-RTD and bottom-HEMT material structure is epitaxied on InP substrate through molecular beam epitaxy. Based on wet chemical etching, metal lift-off and air bridge interconnection technology, RTD and HEMT are fabricated simultaneously. The peak-to-valley current ratio of RTD is 7.7 and the peak voltage is 0.33 V at room temperature. The pinch-off voltage is -0.5 V and the current gain cut-frequency is 30 GHz for a 1.0 μm gate length depletion mode HEMT. The two devices are conformable in current magnitude, which is suitable for the construction of various RTD/HEMT monolithic integration logic circuits. 展开更多
关键词 resonant tunneling diode high electron mobility transistor INP monolithic integration
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Research Progress of Palladium Catalysts for Methane Combustion 被引量:5
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作者 Liu Wenge Guo Deyong Xu Xin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第3期1-9,共9页
Recent research progress and development of the palladium catalysts for methane combustion are described in this study.The influence of active species,precursor,solvent,preparation methodologies,support and dopant on ... Recent research progress and development of the palladium catalysts for methane combustion are described in this study.The influence of active species,precursor,solvent,preparation methodologies,support and dopant on the catalytic activity and thermal stability of the palladium catalysts was discussed.Results of deactivation and poisoning of palladium catalysts were analyzed.Furthermore,possible kinetic models and reaction mechanism were indicated for Pd catalysts. 展开更多
关键词 METHANE catalytic combustion palladium catalysts KINETICS
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Shallow Donor Impurity Ground State in a GaAs/AlAs Spherical Quantum Dot within an Electric Field
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作者 YUAN Jian-Hui XIE Wen-Fang HE Li-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期710-714,共5页
Using the configuration-integration methods (CI) [Phys. Rev. B 45 (1992) 19], we report the results of the Hydrogenie-impurity ground state in a GaAs/AIAs spherical quantum dot under an electric field. We discuss ... Using the configuration-integration methods (CI) [Phys. Rev. B 45 (1992) 19], we report the results of the Hydrogenie-impurity ground state in a GaAs/AIAs spherical quantum dot under an electric field. We discuss the variations of the binding energies of the Hydrogenic-impurity ground state as a function of the position of impurity D, the radius R of the quantum dot, and also as a function of electric field F. We find that the ground energy and binding energy of impurity placed anywhere depend strongly on the position of impurity. Also, electric field can largely change the Hydrogenic-impurity ground state only limiting to the big radius of quantum dot. And the differences in energy level and binding energy are observed from the center donor and off-center donor. 展开更多
关键词 DONOR quantum dots binding energy electric field
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A Parallel-based Lifting Algorithm and VLSI Architecture for DWT
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作者 Xiong Chengyi Tian Jinwen +1 位作者 Liu Jian Gao Zhirong 《Journal of Electronics(China)》 2006年第2期244-248,共5页
A novel Parallel-Based Lifting Algorithm (PBLA) for Discrete Wavelet Transform (DWT), exploiting the parallelism of arithmetic operations in all lifting steps, is proposed in this paper. It leads to reduce the cri... A novel Parallel-Based Lifting Algorithm (PBLA) for Discrete Wavelet Transform (DWT), exploiting the parallelism of arithmetic operations in all lifting steps, is proposed in this paper. It leads to reduce the critical path latency of computation, and to reduce the complexity of hardware implementation as well. The detailed derivation on the proposed algorithm, as well as the resulting Very Large Scale Integration (VLSI) architecture, is introduced, taking the 9/7 DWT as an example but without loss of generality. In comparison with the Conventional Lifting Algorithm Based Implementation (CLABI), the critical path latency of the proposed architecture is reduced by more than half from (4Tm + 8Ta)to Tm + 4Ta, and is competitive to that of Convolution-Based Implementation (CBI), but the new implementation will save significantly in hardware. The experimental results demonstrate that the proposed architecture has good performance in both increasing working frequency and reducing area. 展开更多
关键词 Discrete Wavelet Transform (DFT) Lifting scheme PARALLEL Very Large Scale Integration(VLSI)
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Research on the adjustment model of ventilation characteristic parameters based on integrated method of circuit and path
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作者 Ting-gui JIA Shu-gang WANG +1 位作者 Guo-na QU Jian LIU 《Journal of Coal Science & Engineering(China)》 2013年第1期33-37,共5页
Ventilation characteristic parameters are the base of ventilation network solution; however, they are apt to be affected by operating errors, reading errors, airflow stability, and other factors, and it is difficult t... Ventilation characteristic parameters are the base of ventilation network solution; however, they are apt to be affected by operating errors, reading errors, airflow stability, and other factors, and it is difficult to obtain accurate results. In order to check the ventilation characteristic parameters of mines more accurately, the integrated method of circuit and path is adopted to overcome the drawbacks caused by the traditional path method or circuit method in the digital debugging process of ventilation system, which can improve the large local error or the inconsistency between the airflow direction and the actual situation caused by inaccuracy of the ventilation characteristic parameters or checking in the ventilation network solution. The results show that this method can effectively reduce the local error and prevent the pseudo-airflow reversal phenomenon; in addition, the solution results are consistent with the actual situation of mines, and the effect is obvious. 展开更多
关键词 path method circuit method ventilation network adjustment model ventilation characteristic parameter
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Gridless Net Routing of Integrate Circuit with Particle Swarm Optimization Algorithm
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作者 X.C. Huang 《Journal of Energy and Power Engineering》 2011年第9期899-904,共6页
Particle swarm optimization algorithm is presented for the layout of "Integrate Circuit (IC)" design. Particle swarm optimization based on swarm intelligence is a new evolutionary computational tool and is success... Particle swarm optimization algorithm is presented for the layout of "Integrate Circuit (IC)" design. Particle swarm optimization based on swarm intelligence is a new evolutionary computational tool and is successfully applied in function optimization, neural network design, classification, pattern recognition, signal processing and robot technology and so on. A modified algorithm is presented and applied to the layout of IC design. For a given layout plane, first of all, this algorithm generates the corresponding grid group by barriers and nets' ports with the thought ofgridless net routing, establishes initialization fuzzy matrix, then utilizes the global optimization character to find out the best layout route only if it exits. The results of model simulation indicate that PSO algorithm is feasible and efficient in IC layout design. 展开更多
关键词 Particle swarm optimization algorithm gridless net routing layout optimization prufer number.
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