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Data classification method based on network dynamics analysis and cloud model
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作者 王肖霞 杨风暴 +1 位作者 梁若飞 张文华 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期266-271,共6页
In order to reduce amount of data storage and improve processing capacity of the system, this paper proposes a new classification method of data source by combining phase synchronization model in network clusteri... In order to reduce amount of data storage and improve processing capacity of the system, this paper proposes a new classification method of data source by combining phase synchronization model in network clustering with cloud model. Firstly, taking data source as a complex network, after the topography of network is obtained, the cloud model of each node data is determined by fuzzy analytic hierarchy process (AHP). Secondly, by calculating expectation, entropy and hyper entropy of the cloud model, comprehensive coupling strength is got and then it is regarded as the edge weight of topography. Finally, distribution curve is obtained by iterating the phase of each node by means of phase synchronization model. Thus classification of data source is completed. This method can not only provide convenience for storage, cleaning and compression of data, but also improve the efficiency of data analysis. 展开更多
关键词 data classification complex network phase synchronization cloud model
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Microstructure of asymmetric twin-roll cast AZ31 magnesium alloy 被引量:4
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作者 赵虎 何良菊 李培杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2372-2377,共6页
The microstructural distribution along thickness of asymmetric twin-roll cast AZ31 magnesium alloy slab was investigated. It was found that the microstructure along the thickness of the slab was significantly inhomoge... The microstructural distribution along thickness of asymmetric twin-roll cast AZ31 magnesium alloy slab was investigated. It was found that the microstructure along the thickness of the slab was significantly inhomogeneous. There were many deformed bands with flow form near the upper surface of twin-roll cast plate. Very few deformed bands could be seen in the central part of the plate where the dendrites were thick. Fine dendritic structures dominated near the lower surface of the twin-roll cast strip. It is concluded that the shear strain caused by linear velocity difference between surfaces of upper and lower rolls results in the deformed bands of the twin-roll cast slab. Aluminum, zinc and manganese segregate to the boundary of dendrites, while silicon distributes inside the α-Mg solid solution. 展开更多
关键词 AZ31 magnesium alloy asymmetric twin-roll casting deformation bands PRECIPITATE
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2.5Gb/s/ch 0.18μm CMOS Data Recovery Circuit
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作者 刘永旺 王志功 李伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第5期692-695,共4页
A 2.5Gb/s/ch data recovery (DR) circuit is designed for an SFI-5 interface. To make the parallel data bit-synchronization and reduce the bit error rate (BER) ,a delay locked loop (DLL) is used to place the cente... A 2.5Gb/s/ch data recovery (DR) circuit is designed for an SFI-5 interface. To make the parallel data bit-synchronization and reduce the bit error rate (BER) ,a delay locked loop (DLL) is used to place the center of the data eye exactly at the rising edge of the data-sampling clock. A single channel DR circuit was fabricated in TSMC's standard 0. 18μm CMOS process. The chip area is 0. 46mm^2. With a 2^32 - 1 pseudorandom bit sequence (PRBS) input,the RMS jitter of the recovered 2.5Gb/s data is 3.3ps. The sensitivity of the single channel DR is less than 20mV with 10-12 BER. 展开更多
关键词 data recovery delay locked loop bit-synchronization
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某扫描器步进电机驱动电路设计 被引量:1
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作者 张大威 毛林 《中国科技信息》 2015年第10期96-97,共2页
本文以某型扫描器为步进电机的典型应用对象,在分析了步进电机驱动原理的基础上对步进电机的驱动电路进行了研究,完成了基于专用集成步进电机驱动芯片DRV8811的步进电机驱动电路设计。并对此步进电路的驱动电路进行了调试测试,测试结果... 本文以某型扫描器为步进电机的典型应用对象,在分析了步进电机驱动原理的基础上对步进电机的驱动电路进行了研究,完成了基于专用集成步进电机驱动芯片DRV8811的步进电机驱动电路设计。并对此步进电路的驱动电路进行了调试测试,测试结果表明该驱动电路工作可靠,满足设计需求。最后,对本文的研究工作和所取得的研究成果进行了总结,并结合实际开发中的体会,提出了进一步的展望。 展开更多
关键词 步进电机 驱动电路设计 电机驱动电路 相步 步距角 应用对象 斩波电路 设计需求 驱动模块 启停控制
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Study on Synchro-Epitaxy of Poly-and Single Crystal Silicon
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作者 胡冬青 李思渊 王永顺 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1381-1385,共5页
Synchro-epitaxy is introduced and a “two periods epitaxy” process is proposed.The influence of the flows of SiH 4 N 1,N 2,deposition time t 1,t 2,and epitaxial temperature T on epilayer quality (embodied by α)... Synchro-epitaxy is introduced and a “two periods epitaxy” process is proposed.The influence of the flows of SiH 4 N 1,N 2,deposition time t 1,t 2,and epitaxial temperature T on epilayer quality (embodied by α) is reported.The shorter initial inducing time t 1 and larger flows of SiH 4 are,the wider single crystal strips are.But the quality of epilayer may be poor.The optimum conditions are:N 1=13.1~17.5sccm,N 2=7.0~7.88sccm,and t 1=30~50s.The influence of temperature is complex:when T is lower than 980℃,single crystal strips increase with T ;when T is higher than 980℃,single crystal strips decrease with T.It reaches maximum near 980℃. 展开更多
关键词 synchro-epitaxy NUCLEATION CVD
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Low Temperature One Step Synthesis of Barium Titanate: Particle Formation Mechanism and Large-scale Synthesis 被引量:2
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作者 沈志刚 张维维 +1 位作者 陈建峰 甄崇礼 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第5期642-648,共7页
The formation of BaTiO3 nanoparticles via the reaction of BaCl2, TiCl4 and NaOH in aqueous solution has been systematically studied. The formation of BaTiO3 from the ionic precursors has been elucidated to be a very r... The formation of BaTiO3 nanoparticles via the reaction of BaCl2, TiCl4 and NaOH in aqueous solution has been systematically studied. The formation of BaTiO3 from the ionic precursors has been elucidated to be a very rapid process, occurring at temperature higher than 60℃. Furthermore, the particle size could be controlled by the proper selection of the synthesis conditions (e.g. reactant concentration of 0.5—1.0mol·L-1, temperature of 80— 95℃ and pH≥13). A two-step precipitation mechanism was proposed. The first stage of the synthesis involved the formation of amorphous Ti-rich gel phase. The second stage of the synthesis was the reaction between the amor-phous phase and the solution-based Ba2+ ions, which led to the crystallization of BaTiO3. Based on the particle for-mation mechanism, a novel method, high gravity reactive precipitation, was proposed and used to mass production of BaTiO3 of average particle size of about 60 nm and with narrow particle size distribution. Because it could break up the amorphous Ti-rich gel into small pieces, intensify mass transfer, promote the reaction rate of amorphous Ti-rich gel with Ba2+ ions. 展开更多
关键词 nanoparticles synthesis particle formation mechanism barium titanate perovskite phase high gravity reactive precipitation
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Segmented Spiral Waves and Anti-phase Synchronization in a Model System with Two Identical Time-Delayed Coupled Layers 被引量:2
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作者 YUAN Guo-Yong YANG Shi-Ping +1 位作者 WANG Guang-Rui CHEN Shi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期174-180,共7页
In this paper, we consider a model system with two identical time-delayed coupled layers. Synchronization and anti-phase synchronization are exhibited in the reactive system without diffusion term. New segmented spira... In this paper, we consider a model system with two identical time-delayed coupled layers. Synchronization and anti-phase synchronization are exhibited in the reactive system without diffusion term. New segmented spiral waves, which are constituted by many thin trips, are found in each layer of two identical time-delayed coupled layers, and are different from the segmented spiral waves in a water-in-oil aerosol sodium bis(2-ethylhexyl) sulfosuccinate (AOT) microemulsion (ME) (BZ-AOT system), which consists of many small segments. "Anti-phase spiral wave synchronization" can be realized between the first layer and the second one. For different excitable parameters, we also give the minimum values of the coupling strength to generate segmented spiral waves and the tip orbits of spiral waves in the whole bilayer. 展开更多
关键词 spiral wave SYNCHRONIZATION anti-phase synchronization
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Automated Phase-measuring Profilometry of 3-D Diffuse Objects Using a Single Phase Step Method 被引量:2
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作者 ZHAO Hong,SONG Yuanhe,CHEN Wenyi,TAN Yushan (Research Institute for Laser & Infrared Application, Xi’an Jiaotong University,Xi’an 710049,CHN) 《Semiconductor Photonics and Technology》 CAS 1998年第1期25-30,35,共7页
The technique of phase measuring profilometry using a single phase step method is proposed.This method can automatically obtain phase value at each pixel by using a discret cosine transform algorithm.The method is abl... The technique of phase measuring profilometry using a single phase step method is proposed.This method can automatically obtain phase value at each pixel by using a discret cosine transform algorithm.The method is able to automatically recognize any position between depression and elevation on an object surface.Theoretical analysis and experimental verification are presented. 展开更多
关键词 Discret Cosine Transform Noncontact Optical Measurement One Step Phase-shifting Phase-measuring 3-D Profilometry
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Phase Synchronization of Coupled Rossler Oscillators: Amplitude Effect 被引量:1
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作者 LI Xiao-Wen ZHENG Zhi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期265-269,共5页
Phase synchronization of two linearly coupled Rossler oscillators with parameter misfits is explored. It is found that depending on parameter mismatches, the synchronization of phases exhibits different manners. The s... Phase synchronization of two linearly coupled Rossler oscillators with parameter misfits is explored. It is found that depending on parameter mismatches, the synchronization of phases exhibits different manners. The synchronization regime can be divided into three regimes. For small mismatches, the amplitude-insensitive regime gives the phase-dominant synchronization; When the parameter misfit increases, the amplitudes and phases of oscillators are correlated) and the amplitudes will dominate the synchronous dynamics for very large mismatches. The lag time among phases exhibits a power law when phase synchronization is achieved. 展开更多
关键词 phase synchronization amplitude eiiect
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Two Feasible Schemes for Preparing Cluster States with Ion-Trap Setup 被引量:2
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作者 WANG Xin-Wen CAO Shuai XIA Li-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1217-1220,共4页
We present two schemes for preparing cluster states with atomic qubits in an ion-trap system. In the first scheme an auxiliary atomic level is needed. While in the second scheme an additional classical driven field is... We present two schemes for preparing cluster states with atomic qubits in an ion-trap system. In the first scheme an auxiliary atomic level is needed. While in the second scheme an additional classical driven field is used, and the multi-ion cluster states can be generated by one step. Both the schemes are insensitive to thermal motion of the ions, all the facilities used in them are well within state of the art. 展开更多
关键词 ION-TRAP cluster states one-step implementation controlled phase gates
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Theory of Dynamics In-Phase Locking and Quasi-Period Synchronization in Two Mutually Coupled Multi-Quantum-Well Lasers 被引量:1
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作者 YAN Sen-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期481-488,共8页
Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but... Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but detuning, in detain. It is proved that the coupling level determines stability of the lasers by analyzing the eigenvalue equation. Critical case of locking is discussed via the phase difference equation. Quasi-period and stable states in the two lasers are investigated via varying the current, detuning and coupling level. 展开更多
关键词 in-phase locking SYNCHRONIZATION multi-quantum-well laser COUPLING
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Harmonic detection an AC excited generation system based on in-phase correlation filtering 被引量:1
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作者 贺益康 孙丹 +1 位作者 王文举 石赟 《Journal of Zhejiang University Science》 CSCD 2002年第1期65-71,共7页
The paper reports results of investigation on the harmonic detection technique of a complicated power supply system such as an AC excited generation system, which has a variable fundamental frequency and low order har... The paper reports results of investigation on the harmonic detection technique of a complicated power supply system such as an AC excited generation system, which has a variable fundamental frequency and low order harmonics with rich sub-harmonics whose frequencies are lower than the fundamental one. The in-phase correlation filtering technique, based on the frequency shifting principle, is proposed in this paper.Theoretical analysis and experimental results validate the effectiveness of this technique for the harmonic detections of AC excited generation systems. 展开更多
关键词 in\|phase correlation filtering harmonic detection AC excited generation system
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Research and simulation on synchronization algorithm of PSS in a 5G system based on block cross-correlation 被引量:1
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作者 Zheng Ruimen Wang Xiaojun +1 位作者 Pan Wei Chen Xiaoshu 《Journal of Southeast University(English Edition)》 EI CAS 2021年第3期245-250,共6页
In response to the downlink synchronization requirements of the user equipment(UE)or third-party radio equipment in fifth-generation(5G)mobile communication systems,a synchronization algorithm of primary synchroni-zat... In response to the downlink synchronization requirements of the user equipment(UE)or third-party radio equipment in fifth-generation(5G)mobile communication systems,a synchronization algorithm of primary synchroni-zation signal(PSS)was designed and developed in the 5G system based on block cross-correlation.According to the new characteristics of the 5G synchronization channel and broadcast channel,starting from the traditional downlink synchronization algorithm of long-term evolution(LTE),the detection performance of the algorithm under a low signal-to-noise ratio(SNR)is improved by introducing an incoherent accumulation,and the new scheme of joint coarse frequency offset estimation is used to improve the frequency offset estimation performance.Finally,the performance of the proposed synchronization algorithm is verified by conducting a simulation on a 5G downlink simulation platform based on MATLAB software.Simulation results show that the improved downlink synchronization algorithm has stable performance in the tapped delay line-C(TDL-C)and additive white Gaussian noise(AWGN)channels with large frequency deviation and low SNR. 展开更多
关键词 fifth-generation(5G)cell search downlink synchronization cross-correlation detection frequency offset estimation
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Synchronization of Chaotic Intensities and Phases in an Array of N Lasers 被引量:5
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作者 SUNJian ZHUShi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期233-239,共7页
A linear array of N mutually coupled single-mode lasers is investigated. It is shown that the intensities of N lasers are chaotically synchronized when the coupling between lasers is relatively strong. The chaotic syn... A linear array of N mutually coupled single-mode lasers is investigated. It is shown that the intensities of N lasers are chaotically synchronized when the coupling between lasers is relatively strong. The chaotic synchronization of intensities depends on the location of the lasers in the array. The chaotic synchronization appears between two outmost lasers, the second two outmost lasers, etc. There is no synchronization between nearest neighbors of the lasers. If the number of N is odd, the middle laser is never synchronized between any lasers. The chaotic synchronization of phases between nearest lasers in the array is examined by using the analytic signal and the Gaussian filter methods based on the peak of the power spectrum of the intensity. It can be seen that the message of chaotic intensity synchronization is conveyed through the phase synchronization. 展开更多
关键词 chaotic synchronization intensity phase linear array solid state lasers
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A simple rectification method for linear multi-baseline stereovision system 被引量:1
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作者 杜歆 李宏东 顾伟康 《Journal of Zhejiang University Science》 CSCD 2004年第5期567-571,共5页
The linear multi-baseline stereo system introduced by the CMU-RI group has been proven to be a very effective and robust stereovision system. However, most traditional stereo rectification algorithms are all designed ... The linear multi-baseline stereo system introduced by the CMU-RI group has been proven to be a very effective and robust stereovision system. However, most traditional stereo rectification algorithms are all designed for binocular stereovision system, and so, cannot be applied to a linear multi-baseline system. This paper presents a simple and intuitional method that can simultaneously rectify all the cameras in a linear multi-baseline system. Instead of using the general 8-parameter homography transform, a two-step virtual rotation method is applied for rectification, which results in a more specific transform that has only 3 parameters, and more stability. Experimental results for real stereo images showed the presented method is efficient. 展开更多
关键词 RECTIFICATION Multi-baseline STEREOVISION
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Alternate Phase Synchronization in Coupled Chaotic Oscillators
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作者 ZHENGZhi-Gang ZHOUChang-Song 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第4期419-423,共5页
Phase locking dynamics in coupled chaotic oscillators is investigated. For chaotic systems with a poorly coherent phase variable, the imperfect phase locking can be observed before the onset of a complete phase synchr... Phase locking dynamics in coupled chaotic oscillators is investigated. For chaotic systems with a poorly coherent phase variable, the imperfect phase locking can be observed before the onset of a complete phase synchronization. The temporal alternations among phase lockings are found, which originate from an overlap of Arnold tongues. 展开更多
关键词 phase synchronization Arnold tongues Lyapunov exponent
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Preparation of MIL-88B(Fe_(x),Co_(1‒x))catalysts and their application in one-step liquid-phase methanol oxidation to methyl formate using H_(2)O_(2)
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作者 Jianfang Liu Zhenzhen Ran +1 位作者 Qiyan Cao Shengfu Ji 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第12期2254-2264,共11页
The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream products.The development of highly efficient and stable catalysts is critical for... The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream products.The development of highly efficient and stable catalysts is critical for this transformation.In this study,a series of MIL-88B(Fe_(x),Co_(1‒x))bimetallic catalysts with different Fe/Co molar ratios were prepared through a one-pot hydrothermal method.X-ray diffraction,scanning electron microscopy,high-resolution transmission electron microscopy,energy dispersive spectroscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,N2 adsorption-desorption,and inductively coupled plasma-mass spectrometry characterization were performed to elucidate the structure of the catalysts.The activity of the catalysts were assessed in the one-step oxidation of methanol to methyl formate with H_(2)O_(2)in a liquid-phase batch reactor.The results show that the MIL-88B(Fe_(x),Co_(1‒x))catalysts exhibit uniform needle-like morphologies with an average length and width of 400-600 nm and 100-150 nm,respectively.Co^(2+)is incorporated into the framework by partially replacing Fe^(3+)in MIL-88B.Moreover,the catalyst efficiently promoted the conversion of methanol to methyl formate.When MIL-88B(Fe_(0.7),Co_(0.3))catalyst was used with a molar ratio of H_(2)O_(2)to methanol of 0.5 at 80℃for 60 min,34.8%methanol conversion was achieved,and the selectivity toward methyl formate was 67.6%.The catalysts also showed great stability with a steady conversion and selectivity even after four cycles.The preliminary oxidation mechanism was also studied.It was determined that H_(2)O_(2)is first adsorbed on the Fe^(3+)sites and subsequently activates these sites.Methanol is adsorbed by the O atoms of the framework through hydrogen bonding and is gradually oxidized to formic acid.Subsequently,formic acid reacts with the residual methanol at the Fe^(3+)and Co^(2+)Lewis acid sites to form methyl formate. 展开更多
关键词 Bimetal-organic frameworks Methanol oxidation Liquid phase One-step transformation Methyl formate
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Co-extraction of valuable metals and kinetics analysis in chlorination process of low-grade nickel-copper sulfide ore 被引量:3
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作者 Wen-ning MU Teng-fei XIAO +3 位作者 Shuang-zhi SHI Xue-qing XU Hao CHENG Yu-chun ZHAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期2033-2045,共13页
To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore,chlorination roasting with NH;Cl followed by a water leaching process was investigated.The results show that 98.4%Ni and 98.5%Cu can be sync... To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore,chlorination roasting with NH;Cl followed by a water leaching process was investigated.The results show that 98.4%Ni and 98.5%Cu can be synchronously extracted when the ore particle size is 75-80μm,the roasting time is 2 h,the mass ratio of NH;Cl to ore is 1.6:1 and the roasting temperature is 550°C.The evolution behavior of various minerals was elucidated using X-ray diffraction(XRD)coupled with scanning electron microscopy(SEM).The kinetics of the chlorination process based on the differential thermal and thermogravimetric analysis(DTA-TG)data was analyzed by Kissinger method and Flynn-Wall-Ozawa(FWO)method.The chlorination process of low-grade nickel-copper sulfide ore mainly contains two stages:the decomposition of NH;Cl and the chlorination of ore.The maximum apparent activation energies(Ea)at two stages are determined to be 114.8 and 144.6 kJ/mol,respectively.The condensed product of exhaust gas is determined to be ammonium chloride,which can be recycled as the reactant again,making the process economic and clean. 展开更多
关键词 low-grade nickel-copper sulfide ore chlorination roasting synchronous extraction phase evolution KINETICS
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Phase Desynchronization as a Mechanism for Transitions to High—Dimensional Chaos
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作者 ZHENGZhi-Gang HUGang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期682-688,共7页
Phase is an important degree of freedom in studies of chaotic oscillations. Phase coherence and localization in coupled chaotic elements are studied. It is shown that phase desynchronization is a key mechanism respons... Phase is an important degree of freedom in studies of chaotic oscillations. Phase coherence and localization in coupled chaotic elements are studied. It is shown that phase desynchronization is a key mechanism responsible for the transitions from low- to high-dimensional chaos. The route from low-dimensional chaos to high-dimensional toroidal chaos is accompanied by a cascade of phase desynchronizations. Phase synchronization tree is adopted to exhibit the entrainment process. This bifurcation tree implies an intrinsic cascade of order embedded in irregular motions. 展开更多
关键词 phase synchronization phase localization Lyapunov exponents
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Artificial Neural Network in Harmonic Reduction of STATCOM 被引量:1
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作者 LiHongmei LiZhenran ZhengPeiying 《Electricity》 2005年第1期34-37,共4页
To eliminate harmonic pollution incurred from the static synchronous compensator(STATCOM), a method of applying artificial neural network is presented. When PWM wave is formed based on the harmonic suppression theory,... To eliminate harmonic pollution incurred from the static synchronous compensator(STATCOM), a method of applying artificial neural network is presented. When PWM wave is formed based on the harmonic suppression theory, a concave is set on certain angle of the square wave to suppress unnecessary harmonics, by timely and on-line determining the chopping angle corresponding to respective harmonics through artificial neural network, i.e. by setting the position of concave to eliminate corresponding harmonics, the harmonic component on output voltage of the inverter can be improved. To conclude through computer simulation test, the perfect control effect has been proved. 展开更多
关键词 static synchronous compensator (STATCOM) artificial neural network(ANN) HARMONICS
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