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Direction of arrival estimation method based on quantum electromagnetic field optimization in the impulse noise 被引量:1
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作者 DU Yanan GAO Hongyuan CHEN Menghan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期527-537,共11页
In order to resolve direction finding problems in the impulse noise,a direction of arrival(DOA)estimation method is proposed.The proposed DOA estimation method can restrain the impulse noise by using infinite norm exp... In order to resolve direction finding problems in the impulse noise,a direction of arrival(DOA)estimation method is proposed.The proposed DOA estimation method can restrain the impulse noise by using infinite norm exponential kernel covariance matrix and obtain excellent performance via the maximumlikelihood(ML)algorithm.In order to obtain the global optimal solutions of this method,a quantum electromagnetic field optimization(QEFO)algorithm is designed.In view of the QEFO algorithm,the proposed method can resolve the difficulties of DOA estimation in the impulse noise.Comparing with some traditional DOA estimation methods,the proposed DOA estimation method shows high superiority and robustness for determining the DOA of independent and coherent sources,which has been verified via the Monte-Carlo experiments of different schemes,especially in the case of snapshot deficiency,low generalized signal to noise ratio(GSNR)and strong impulse noise.Beyond that,the Cramer-Rao bound(CRB)of angle estimation in the impulse noise and the proof of the convergence of the QEFO algorithm are provided in this paper. 展开更多
关键词 direction of arrival(DOA)estimation impulse noise infinite norm exponential kernel covariance matrix maximum-likelihood(ML)algorithm quantum electromagnetic field optimization(QEFO)algorithm Cramer-Rao bound(CRB)
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Experimental Validation and Application of a Phased Array Ultrasonic Testing Model on Sound Field Optimization
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作者 Xiangyu Lei +1 位作者 kan Wirdelius Anders Rosell 《Journal of Modern Physics》 2021年第4期391-407,共17页
In safety dominant industries, nondestructive evaluation (NDE) is crucial in quality assurance and assessment. Phased array ultrasonic testing (PAUT) as one of the NDE methods is more promising compared with conventio... In safety dominant industries, nondestructive evaluation (NDE) is crucial in quality assurance and assessment. Phased array ultrasonic testing (PAUT) as one of the NDE methods is more promising compared with conventional ultrasonic testing (UT) method in terms of inspection speed and flexibility. To incorporate PAUT, the techniques should be qualified, which traditionally is performed by extensive physical experiments. However, with the development of numerical models simulating UT method, it is expected to complement or partly replace the experiments with the intention to reduce costs and operational uncertainties. The models should be validated to ensure its consistency to reality. This validation work can be done by comparing the model with other validated models or corresponding experiments. The purpose of current work focuses on the experimental validation of a numerical model, simSUNDT, developed by the Chalmers University of Technology. Validation is conducted by comparing different data presentations (A-, B- and C-scan) from experimental and simulated results with some well-defined artificial defects. Satisfactory correlations can be observed from the comparisons. After the validation, sound field optimization work aiming at retrieving maximized echo amplitude on a certain defect can be started using the model. This also reveals the flexibility of parametric studies using simulation models. 展开更多
关键词 EXPERIMENTS SIMULATION VALIDATION Sound field optimization
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Optimization of Field Arrangement of Doublecropping Glutinous Sorghum and Soybean Intercropping Pattern
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作者 尹学伟 张晓春 +2 位作者 王培华 陈红 王红梅 《Agricultural Science & Technology》 CAS 2015年第6期1110-1114,共5页
In order to reduce successive cropping obstacles, optimize field arrange-ment of double-cropping of sorghum and soybean and improve yields, the research used Guojiaohong No.1 and Nandou No.12 as raw materials to explo... In order to reduce successive cropping obstacles, optimize field arrange-ment of double-cropping of sorghum and soybean and improve yields, the research used Guojiaohong No.1 and Nandou No.12 as raw materials to explore the effects of different field arrangements on yield and benefits of double-cropping. The results indicated that with the double-cropping, both of gross yield and output value were higher compared with single-cropping treatments; yield, thousand-grain weight, the weight of grain per ear, and ear length of the 1st-season glutinous sorghum de-creased as compartment width grew, and of regenerated sorghum and soybean changed from increasing to decreasing. Specifical y, with double-cropping system, gross yield of glutinous sorghum reached the highest at 8 352.9 kg/hm2 with com-partment width of 1.7 m and soybean yield the highest at 1 888.95 kg/hm2 with compartment width of 1.8 m. Additional y, gross output value and net incomes achieved the highest at 47 293.92 yuan/hm2 and 29 976.42 kg/hm2 for the two crops, with compartment width of 1.7 m, fol owed by the treatment with compart-ment width of 1.8 m. In general, the treatments with compartment widths of 1.7 and 1.8 m are optimal field arrangement. Additional y, output-to-input ratio was the high-est in the treatment with single-cropping glutinous sorghum and the least in the treatment with single-cropping soybeans. 展开更多
关键词 Double-cropping glutinous sorghum SOYBEAN optimization of field ar-rangement
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Optimal Microwave Radiation Field Parameters for Mercury Ion Microwave Frequency Standards 被引量:2
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作者 Zhi-Hui Yang Hao Liu +5 位作者 Yue- Hong He Man Wang Yong-Quan Wan Yi-He Chen Lei She Jiao-Mei Li 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期21-24,共4页
We propose a method to determine the optimal power of the microwave resonance transition that simultaneously improves the signal-to-noise ratio and reduces line width based on saturation broadening theory and experime... We propose a method to determine the optimal power of the microwave resonance transition that simultaneously improves the signal-to-noise ratio and reduces line width based on saturation broadening theory and experiment. Saturation broadening spectra of the ground state hyperfine transition of trapped 199Hg+ ions are measured and analyzed. The value of the optimal microwave power is obtained by using the proposed method and is verified. Rabi oscillations decay spectra of trapped 199Hg+ ions are observed and the optimal microwave irradiation time for the maximum transition signal intensity is determined. This work will help to improve the short-term frequency stability of the mercury ion microwave frequency standard. 展开更多
关键词 of on IT Optimal Microwave Radiation field Parameters for Mercury Ion Microwave Frequency Standards DBM IS for
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Kriging-boosted CR modeling for prompt infill drilling optimization
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作者 Elizaveta S.Gladchenko Anna E.Gubanova +1 位作者 Denis M.Orlov Dmitry A.Koroteev 《Petroleum》 EI CSCD 2024年第1期39-48,共10页
The capacitance-resistance model(CRM)has been a useful physics-based tool for obtaining production forecasts for decades.However,the model's limitations make it difficult to work with real field cases,where a lot ... The capacitance-resistance model(CRM)has been a useful physics-based tool for obtaining production forecasts for decades.However,the model's limitations make it difficult to work with real field cases,where a lot of various events happen.Such events often include new well commissioning(NWC).We introduce a workflow that combines CRM concepts and kriging into a single tool to handle these types of events during history matching.Moreover,it can be used for selecting a new well placement during infill drilling.To make the workflow even more versatile,an improved version of CRM was used.It takes into account wells shut-ins and performed workovers by additional adjustment of the model coefficients.By preliminary re-weighing and interpolating these coefficients using kriging,the coefficients for potential wells can be determined.The approach was validated using both synthetic and real datasets,from which the cases of putting new wells into operation were selected.The workflow allows a fast assessment of future well performance with a minimal set of reservoir data.This way,a lot of well placement scenarios can be considered,and the best ones could be chosen for more detailed studies. 展开更多
关键词 Capacitance-resistance model(CRM) field development optimization Infill drilling Interwell connectivity KRIGING New well commissioning(NWC)
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Optimization Design of Magnetic Field on Cold Yoke Superconducting Solenoid
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作者 李青 马力祯 +3 位作者 何源 吴巍 卞文龙 姚庆高 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第z1期49-52,共4页
The optimized design of magnetic field for a cold yoke superconducting solenoid is introduced in this paper. Using some kinds of optimization designs and OPERA,we optimize the main solenoid,cold yoke and compensated w... The optimized design of magnetic field for a cold yoke superconducting solenoid is introduced in this paper. Using some kinds of optimization designs and OPERA,we optimize the main solenoid,cold yoke and compensated winding.Through this design,the requests of the superconducting solenoid are realized. 展开更多
关键词 superconducting magnet cold yoke optimization design of magnetic field orthogonal design
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Addition Sequence Method of Scalar Multiplication of Elliptic Curve over OEF 被引量:2
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作者 LIUDuo DAIYi-qi 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期174-178,共5页
A new elliptic curve scalar multiplication algorithm is proposed. Thealgorithm uses the Frobenius map on optimal extension field (OEF) and addition sequence We introducea new algorithm on generating addition sequence ... A new elliptic curve scalar multiplication algorithm is proposed. Thealgorithm uses the Frobenius map on optimal extension field (OEF) and addition sequence We introducea new algorithm on generating addition sequence efficiently and also give some analysis about it.Based on this algorithm, a new method of computing scalar multiplication of elliptic curve over anOEF is presented. The new method is more efficient than the traditional scalar multiplicationalgorithms of elliptic curve over OEF. Thecomparisons of traditional method and the new method arealso given. 展开更多
关键词 CRYPTOLOGY elliptic curve optimal extension field FROBENIUS additionsequence
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A Heuristic Method of Scalar Multiplication of Elliptic Curve over OEF 被引量:1
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作者 刘铎 罗平 戴一奇 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第2期177-183,共7页
Elliptic curve cryptosystem is the focus of public key cryptology nowadays, for it has many advantages RSA lacks. This paper introduced a new heuristic algorithm on computing multiple scalar multiplications of a given... Elliptic curve cryptosystem is the focus of public key cryptology nowadays, for it has many advantages RSA lacks. This paper introduced a new heuristic algorithm on computing multiple scalar multiplications of a given point. Based on this algorithm, a new method of computing scalar multiplication of elliptic curve over optimal extension field (OEF) using Frobenius map was presented. The new method is more efficient than the traditional ones. In the last part of this paper, the comparison was given in the end. 展开更多
关键词 CRYPTOLOGY elliptic curve optimal extension field FROBENIUS
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Analysis of the operating parameters of a vortex electrostatic precipitator 被引量:3
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作者 Congxiang LU Chengwu YI +1 位作者 Rongiie YI Shiwen LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第2期69-78,共10页
A vortex electrostatic precipitator (VEP) forms a vortex flow field within a precipitator by means of the vertical staggered layout of the double-vortex collecting plate facing the direction of the gas flow. The ion... A vortex electrostatic precipitator (VEP) forms a vortex flow field within a precipitator by means of the vertical staggered layout of the double-vortex collecting plate facing the direction of the gas flow. The ion concentrations within the precipitator can be significantly increased. Correspondingly, the charging and coagulation rates of fine particles and particle migration velocity are significantly improved within the VEP. Since it can effectively collect fine particles and reduce precipitator size, VEPs represent a new type of electrostatic precipitator with great application potential. In this work the change curve of the external voltage, gas velocity, row spacing and effective collecting area influencing the precipitation efficiency were acquired through a single-factor experiment. Using an orthogonal regression design, attempts were made to analyze the major operating parameters influencing the collecting efficiency of fine particles, establish a multiple linear regression model and analyze the weights of factors and then acquire quantitative rules relating experimental indicators and factors. The regression model was optimized by MATLAB programming, and we then obtained the optimal factor combination which can enhance the efficiency of fine particle collection. The final optimized result is that: when gas velocity is 3.4 m s-1, the external voltage is 18 kV, row spacing is 100 mm and the effective collecting area is 1.13 m2, the rate of fine particle collection is 89.8867%. After determining and analyzing the state of the internal flow field within the VEP by particle image velocimetry (PIV), the results show that, for a particular gas velocity, a vortex zone and laminar zone are distinctly formed within the VEP, which increases the ion transport ratio as well as the charging, coagulation and collection rates of fine particles within the precipitator, thus making further improvements in the efficiency of fine particle collection. 展开更多
关键词 fine particles vortex electrostatic precipitator regression model optimization design vortex flow field
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A fault-tolerant triple-redundant voice coil motor for direct drive valves:Design, optimization, and experiment 被引量:4
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作者 Wu Shuai Jiao Zongxia +2 位作者 Yan Liang Yu Juntao Chen Chin-Yin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期1071-1079,共9页
A direct drive actuator (DDA) with direct drive valves (DDVs) as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor (TRVCM) used ... A direct drive actuator (DDA) with direct drive valves (DDVs) as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor (TRVCM) used for redundant DDVs. The TRVCM features electrical/mechanical hybrid triple-redundancy by securing three stators along with three moving coils in the same frame. A permanent magnet (PM) Halbach array is employed in each redundant VCM to simplify the system structure. A back-to-back design between neighborly redundancies is adopted to decouple the magnetic flux linkage. The particle swarm optimization (PSO) method is implemented to optimize design parameters based on the analytical magnetic circuit model. The optimization objective function is defined as the acceleration capacity of the motor to achieve high dynamic performance. The optimal geometric parameters are verified with 3D magnetic field finite element analysis (FEA). A research prototype has been developed for experimental purpose. The experimental results of magnetic field density and force output show that the proposed TRVCM has great potential of applications in DDA systems. 展开更多
关键词 Direct drive valve Hydraulic flight control Magnetic field optimization Particle swarm optimization Redundant motor
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Enhancement of laminar flow heat transfer with single/doubleinclined ribs for unilaterally-heated channel 被引量:4
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作者 WANG XiangYu XU XiangHua LIANG XinGang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第7期2108-2118,共11页
To deal with the aerodynamic heating on the aircraft surface,a potential solution is to utilize liquid cooling via the channels in part of the fuselage.This is a typical problem of flow and heat transfer in channels w... To deal with the aerodynamic heating on the aircraft surface,a potential solution is to utilize liquid cooling via the channels in part of the fuselage.This is a typical problem of flow and heat transfer in channels with unilaterally-heated surfaces.The enhancement of heat transfer in the channel is significant due to the high heating flux.The optimal velocity and temperature fields are obtained first based on the field synergy optimization method.Four rib configurations are proposed to produce the longitudinal vortices suggested by the optimal velocity field.The flow and heat transfer characteristics of different rib configurations are obtained by numerical simulation.The numerical simulations show that the heat transfer enhancement of the rib configurations are quite different,but the pressure drop increases similarly in the laminar flow range of Re = 500–1500.The mechanism of heat transfer enhancement with the single/double-inclined ribs for the unilaterally-heated channel is analysed.The best enhancement of geometric parameter among the investigated parameters such as the angle,length,radius and the spacing of the ribs is obtained. 展开更多
关键词 heat transfer enhancement field synergy optimization inclined ribs unilaterally-heated channel
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Development of a superconducting solenoid for CADS 被引量:1
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作者 吴巍 王志军 +10 位作者 吴北民 韩少斐 倪东升 梅恩铭 杨文杰 朱丽 郑石钧 杨通军 杨晓亮 马力祯 何源 《Chinese Physics C》 SCIE CAS CSCD 2014年第1期75-78,共4页
A superconducting focusing solenoid has been designed and developed for the China Accelerator Driven System (CADS). In order to meet the requirement of focusing strength and fringe field while minimizing the physica... A superconducting focusing solenoid has been designed and developed for the China Accelerator Driven System (CADS). In order to meet the requirement of focusing strength and fringe field while minimizing the physical size of the solenoid, the novel optimizing design method based on a linear programming method was employed. In this report, the design of the solenoid including magnetic field optimization, mechanical design and quench protection will be introduced. The solenoid has been fabricated and tested. The testing results show that the central field reached 8.4 T and the stray field was lower than 50 Gauss in the cavity zone. 展开更多
关键词 ADS FOCUSING superconducting solenoid magnetic field optimization stray field
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Study on Process Technology of Gas Bubbling Curtain Substituting Dam in the Tundish of Slab Casting
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作者 JIN You-lin, SHEN Chang, ZHANG Jian-ping, ZHANG Jian (Technology Center of Ma’anshan Iron and Steel Co, Ltd , Ma’anshan 24300, Anhui, China) 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第S2期256-262,共7页
This paper presents experimental results from physical and mathematical simulation of liquid steel flow in the tundish adopting gas bubbling curtain substituting dam and industrial trials have been investigated based ... This paper presents experimental results from physical and mathematical simulation of liquid steel flow in the tundish adopting gas bubbling curtain substituting dam and industrial trials have been investigated based the experimental results. Physical and mathematical simulation results show the gas bubbling curtain can improve pattern of liquid flow in the tundish , accelerate inclusions flotation,and simultaneity metallurgy effect has been further improved when combining weir and turbulence inhibitor. The industrial trial results confirm that content of oxygen , nitrogen and inclusions in continuous casting billets have been reduced when gas bubbling curtain combining weir and turbulence inhibitor. 展开更多
关键词 gas bubbling curtain physical simulation flow field optimization mathematical simulation
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Color retargeting:Interactive time-varying color image composition from time-lapse sequences 被引量:7
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作者 Shao-Ping Lu Guillaume Dauphin +1 位作者 Gauthier Lafruit Adrian Munteanu 《Computational Visual Media》 2015年第4期321-330,共10页
In this paper,we present an interactive static image composition approach,namely color retargeting,to flexibly represent time-varying color editing effect based on time-lapse video sequences.Instead of performing prec... In this paper,we present an interactive static image composition approach,namely color retargeting,to flexibly represent time-varying color editing effect based on time-lapse video sequences.Instead of performing precise image matting or blending techniques,our approach treats the color composition as a pixel-level resampling problem. In order to both satisfy the user's editing requirements and avoid visual artifacts,we construct a globally optimized interpolation field. This field defines from which input video frames the output pixels should be resampled.Our proposed resampling solution ensures that(i) the global color transition in the output image is as smooth as possible,(ii) the desired colors/objects specified by the user from different video frames are well preserved,and(iii) additional local color transition directions in the image space assigned by the user are also satisfied.Various examples have been shown to demonstrate that our efficient solution enables the user to easily create time-varying color image composition results. 展开更多
关键词 time-lapse sequence image composition color retargeting time-varying transition optimized interpolation field
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Size-Controllable Metal Chelates as Both Light Scattering Centers and Electron Collection Layer for High-Performance Polymer Solar Cells
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作者 Hao Liu Runnan Yu +5 位作者 Yiming Bai Yan Zeng Yuanping Yi Jun Lin Jianhui Hou Zhan’ao Tan 《CCS Chemistry》 CAS 2021年第10期37-49,共13页
An electron collection layer(ECL)between a photoactive overlay and an electrode plays a crucial role in optimizing the light field and charge extraction in bulk-heterojunction(BHJ)polymer solar cells(PSCs).However,the... An electron collection layer(ECL)between a photoactive overlay and an electrode plays a crucial role in optimizing the light field and charge extraction in bulk-heterojunction(BHJ)polymer solar cells(PSCs).However,the typical thickness of the photoactive layer is thinner than its optical path lengths,limiting further improvement of light absorption and device performance. 展开更多
关键词 metal chelates polymer solar cells hafni-um acetylacetone scattering center optimizing light field
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