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Assessment of Dependent Performance Shaping Factors in SPAR-H Based on Pearson Correlation Coefficient 被引量:1
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作者 Xiaoyan Su Shuwen Shang +2 位作者 Zhihui Xu Hong Qian Xiaolei Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1813-1826,共14页
With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in th... With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method. 展开更多
关键词 Reliability evaluation human reliability analysis SPAR-H performance shaping factors DEPENDENCE pearson correlation analysis
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Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review
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作者 Xuemeng Gan Shaofu Li +1 位作者 Shunyuan Xiao Yafeng Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期413-426,共14页
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ... The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review. 展开更多
关键词 powder metallurgy titanium sintering densification oxygen scavenging accurate shaping
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Asia-Pacific Regional Economic Cooperation Under the Reshaping of Global Production and Supply Chains
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作者 Liu Chenyang 《Contemporary World》 2024年第3期20-25,共6页
As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increas... As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increasingly close manner.“Benefit-sharing and risk-sharing”,the characteristics of global industry and supply chains,have a profound influence on the distribution of benefits among countries and the effectiveness of global economic governance. 展开更多
关键词 CHAINS intensified shaping
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Binary Phase Shaping and SHG Contrast Ratios
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作者 Tingyao Xiong 《Journal of Applied Mathematics and Physics》 2024年第8期3026-3035,共10页
Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relatio... Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relation between the SHG contrast ratio and the traditional Merit Factor values. And in the light from known results in Merit Factor Problems, we have shown that Legendre Sequences or Jacobi Sequences, are still the best candidates to obtain binary sequences with large SHG contrast ratios. The authors also discussed the SHG behaviors on some sequences obtained from cyclotomic classes over the finite field GF (2l) . 展开更多
关键词 Binary Phase shaping Binary Sequences SHG Contrast Ratio Merit Factor
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A study on the treatment of chloasma with moxibustion based on the theory of“Yang transforming Qi,and Yin shaping”
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作者 Mi Yang Hong-Yi Lan +2 位作者 Hong Wu Xu Wang Xin-Ju Li 《Clinical Research Communications》 2024年第3期23-28,共6页
Background:“Yang Transforming Qi and Yin shaping”comes from“Plain Question Yin and Yang should be like the theory”.Chinese medicine believes that the imbalance of yin and yang is the cause of human diseases.One of... Background:“Yang Transforming Qi and Yin shaping”comes from“Plain Question Yin and Yang should be like the theory”.Chinese medicine believes that the imbalance of yin and yang is the cause of human diseases.One of the strengths of TCM in treating diseases is holistic regulation.The theory of“Yang transforming Qi,and Yin shaping”implies a strong holistic view.Chloasma,one of the common skin diseases,seriously affects the physical and mental health of patients due to its unclear etiology,difficult treatment and easy recurrence.The occurrence and development of chloasma are closely related to internal organs.This paper is based on the theory of internal meridian,“Yang transforming Qi,and Yin shaping”which attaches importance to the concept of“Yang Qi”,from a new understanding of the pathogenesis etiology of chloasma.Methods:The author believes that the incidence of the disease is the deficiency of Yang Qi,which can’t promote the movement of Qi and blood to nourish the face,resulting in tangible material condensation,so proposes that this disease needs to be promoted by Yang transforming Qi and warm to dissipate.Moxibustion belongs to the fire,and its warming effect can dissipate the tangible evil.Results:Combined with clinical practice and the theory of internal meridian,the author elaborated that moxibustion is one of the effective methods for treating chloasma,which provides a new way of thinking for the treatment of chloasma.Conclusion:“Yang Transforming Qi and Yin shaping”can be used to guide the treatment of chloasma. 展开更多
关键词 Yang Transforming Qi and Yin shaping MOXIBUSTION CHLOASMA
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Coin-structured tunable beam shaping assembly design for accelerator-based boron neutron capture therapy for tumors at different depths and sizes 被引量:1
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作者 Zhao‑Peng Qiao Yao‑Cheng Hu +5 位作者 Quan‑Xu Jiang Jing‑Jing Fan Isao Murata Rui‑Rui Liu Bo Wang Sheng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期66-76,共11页
In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other ... In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other cancers.The specifications for designing an epithermal beam are primarily based on the IAEA-TECODC-1223 report,issued in 2001 for reactor neutron sources.Based on this report,the latest perspectives and clinical requirements,we designed an ABNS capable of adjusting the average neutron beam energy.The design was based on a 2.8 MeV,20 mA proton beam bombarding a lithium target to produce neutrons that were subsequently moderated and tuned through a tunable beam shaping assembly(BSA)which can modify the thicknesses and materials of the coin-shaped moderators,back reflectors,filters,and collimators.The simulation results demonstrated that epithermal neutron beams for deep seated tumor treatment,which were generated by utilizing magnesium fluoride with lengths ranging between 28 and 36 cm as the moderator,possessed a treatment depth of 5.6 cm although the neutron flux peak shifts from 4.5 to 1.0 keV.When utilizing a thinner moderator,a less accelerated beam power can meet the treatment requirements.However,higher powers reduced the treatment time.In contrast,employing a thick moderator can reduce the skin dose.In scenarios that required relatively low energy neutron beams,the removal of the thermal neutron filter can raise the thermal neutron flux at the beam port.And the depth of the dose rate peak could be adjusted between 0.25 and 2.20 cm by combining magnesium fluoride and polyethylene coins of different thicknesses.Hence,this device has a better adaptability for the treatment of superficial tumors.Overall,the tunable BSA provides greater flexibility for clinical treatment than common BSA designs that can only adjust the port size. 展开更多
关键词 Boron neutron capture therapy(BNCT) Accelerator-based neutron source(ABNS) Beam shaping assembly(BSA) Treatment depth
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基于Shaping-DDPG模型的变压器负荷预测技术研究 被引量:1
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作者 山宪武 宋秩行 +1 位作者 邱书琦 叶新青 《武汉理工大学学报(信息与管理工程版)》 CAS 2023年第3期377-382,396,共7页
为了协调电力系统供需平衡,降低运维风险和成本,引入Shaping技术改进了深度确定性策略梯度(DDPG)算法,得到Shaping-DDPG预测模型。加入经验回放技术和目标网络技术以消除数据间的关联性;设计变压器网络评估函数来评价变压器网络的优劣状... 为了协调电力系统供需平衡,降低运维风险和成本,引入Shaping技术改进了深度确定性策略梯度(DDPG)算法,得到Shaping-DDPG预测模型。加入经验回放技术和目标网络技术以消除数据间的关联性;设计变压器网络评估函数来评价变压器网络的优劣状态;通过数据处理模块和卷积模块提取原始数据特征,提高变压器系统的感知能力和学习效率。研究表明:与其他算法预测效果相比,Shaping-DDPG模型的RMSE误差平均值(93 MW)最低,比DDPG模型、RNN模型和SVM模型分别降低了42 MW、93 MW和145 MW。相较于非线性变压器负荷系统,Shaping-DDPG模型具有强大的反馈记忆功能,能准确获取负荷序列潜在的变化趋势,在变压器负荷曲线呈现波动时依然能够保证良好的预测能力。该研究为降低电网公司资源浪费和运维成本、协调电网公司与变压器系统之间的供需平衡提供了思路,提高了运作效益。 展开更多
关键词 变压器负荷预测 深度确定性策略梯度 shaping技术 RMSE误差平均值 网络评估函数
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Terahertz shaping technology based on coherent beam combining
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作者 郑晓冉 马丹妮 +2 位作者 蒋广通 张存林 张亮亮 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期484-492,共9页
The generation of terahertz(THz) waves by focusing a femtosecond pulsed laser beam at a distance is able to overcome the strong absorption properties of air and has rapidly attracted the attention of industry. However... The generation of terahertz(THz) waves by focusing a femtosecond pulsed laser beam at a distance is able to overcome the strong absorption properties of air and has rapidly attracted the attention of industry. However, the poor directionality of the THz wave radiation generated by this method is not conducive to THz wave applications. By controlling the morphology of the ultrafast laser-excited plasma filament and its electron density distribution through coherent beam combining technology, we achieve direct THz beam shaping and are able to obtain THz wave radiation of Gaussian or arbitrary transverse distribution. The novel experimental approach proposed in this paper opens up the research field of direct THz wave shaping using plasma. Moreover, it innovates multi-parameter convergence algorithms and, by doing so, has the potential to find beam patterns with higher energy conversion efficiency and break the energy limit of THz waves emitted by lasers at high power. 展开更多
关键词 femtosecond pulsed laser coherent beam combining terahertz wave beam shaping PLASMA
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Pulse-shaping method for real-time neutron/gamma discrimination at low sampling rates
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作者 Jia‑Xin Li Hui‑Liang Hou +2 位作者 Yue‑Feng Huang Mao‑Song Cheng Zhi‑Min Dai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期51-63,共13页
The Na I:Tl scintillator is an innovative material for dual-gamma-ray and neutron detection with a low ^(6)Li concentration.To achieve real-time n/γ discrimination,a zero-crossing time comparison algorithm based on t... The Na I:Tl scintillator is an innovative material for dual-gamma-ray and neutron detection with a low ^(6)Li concentration.To achieve real-time n/γ discrimination,a zero-crossing time comparison algorithm based on trapezoidal pulse shaping was developed.The algorithm can operate efficiently at low sampling rates and was implemented on a single-probe portable digital n/γ discriminator based on a field-programmable gate array.The discriminator and Na I:Tl,^(6)Li detector were tested in a neutron-gamma mixed field produced by an ^(241)Am-Be neutron source to evaluate the performance of the algorithm.The figure of merits was measured as 2.88 at a sampling rate of 50 MHz,indicating that the discriminator with its embedded algorithm has a promising n/γ discrimination capability.Efficient discrimination at sampling rates of 40 and 25 MHz demonstrates that the capability of this method is not limited by low sampling rates. 展开更多
关键词 FPGA NaI:Tl ^(6)Li Real time Neutron/gamma discrimination Pulse shaping
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Magnetic Field-Based Reward Shaping for Goal-Conditioned Reinforcement Learning
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作者 Hongyu Ding Yuanze Tang +3 位作者 Qing Wu Bo Wang Chunlin Chen Zhi Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第12期2233-2247,共15页
Goal-conditioned reinforcement learning(RL)is an interesting extension of the traditional RL framework,where the dynamic environment and reward sparsity can cause conventional learning algorithms to fail.Reward shapin... Goal-conditioned reinforcement learning(RL)is an interesting extension of the traditional RL framework,where the dynamic environment and reward sparsity can cause conventional learning algorithms to fail.Reward shaping is a practical approach to improving sample efficiency by embedding human domain knowledge into the learning process.Existing reward shaping methods for goal-conditioned RL are typically built on distance metrics with a linear and isotropic distribution,which may fail to provide sufficient information about the ever-changing environment with high complexity.This paper proposes a novel magnetic field-based reward shaping(MFRS)method for goal-conditioned RL tasks with dynamic target and obstacles.Inspired by the physical properties of magnets,we consider the target and obstacles as permanent magnets and establish the reward function according to the intensity values of the magnetic field generated by these magnets.The nonlinear and anisotropic distribution of the magnetic field intensity can provide more accessible and conducive information about the optimization landscape,thus introducing a more sophisticated magnetic reward compared to the distance-based setting.Further,we transform our magnetic reward to the form of potential-based reward shaping by learning a secondary potential function concurrently to ensure the optimal policy invariance of our method.Experiments results in both simulated and real-world robotic manipulation tasks demonstrate that MFRS outperforms relevant existing methods and effectively improves the sample efficiency of RL algorithms in goal-conditioned tasks with various dynamics of the target and obstacles. 展开更多
关键词 Dynamic environments goal-conditioned reinforcement learning magnetic field reward shaping
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Nonbinary ldpc-coded probabilistic shaping scheme for MIMO systems based on signal space diversity
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作者 Weimin Kang 《Digital Communications and Networks》 SCIE CSCD 2023年第3期779-787,共9页
This paper first describes a binary Low-Density Parity-Check(LDPC)-coded Probabilistic Shaping(PS)scheme for Multiple-Input Multiple-Output(MIMO)systems based on Signal Space Diversity(SSD).Second,a Nonbinary(NB)LDPC-... This paper first describes a binary Low-Density Parity-Check(LDPC)-coded Probabilistic Shaping(PS)scheme for Multiple-Input Multiple-Output(MIMO)systems based on Signal Space Diversity(SSD).Second,a Nonbinary(NB)LDPC-coded PS scheme for MIMO systems based on SSD is proposed.The first scheme can be used to obtain a shaping gain,whereas the second can also realize a coding gain.The theoretical average mutual information of the optimized rotated quadrature amplitude modulation constellations is analyzed and the simulated error per-formance with 22 and 44 MIMO schemes is investigated.The theoretical average mutual information analysis and simulation results show that the proposed NB LDPC-coded PS scheme for MIMO systems based on SSD is reliable and robust,and is therefore suitable for future wireless communication systems. 展开更多
关键词 Probabilistic shaping Multiple-input multiple-output Signal space diversity Average mutual information
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Science and Technology Innovation and the Reshaping of the International Landscape
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作者 Wang Cungang 《Contemporary World》 2023年第3期8-12,共5页
Science and technology are the first productive force.They play a revolutionary role in the development of history.The emer­gence of major science and technol­ogy innovations usually leads to S&T revolut... Science and technology are the first productive force.They play a revolutionary role in the development of history.The emer­gence of major science and technol­ogy innovations usually leads to S&T revolutions and industrial changes,which in turn stimulate the renewal of methods of production and trig­ger major changes in other aspects of human society. 展开更多
关键词 productive RENEWAL shaping
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Global Economic and Trade Landscape Reshaping and High-Quality Belt and Road Cooperation
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作者 Xu Xiujun 《Contemporary World》 2023年第5期17-21,共5页
At present,a new round of revolution in science,technology and industry is developing profoundly.The global economic and trade development pattern and cooperation mode are also under crucial adjustments.These have bro... At present,a new round of revolution in science,technology and industry is developing profoundly.The global economic and trade development pattern and cooperation mode are also under crucial adjustments.These have brought new challenges and opportunities for promoting trade connectivity included in the Belt and Road Initiative,and have also endowed the initiative a new role in the reshaping of the global economic and trade landscape. 展开更多
关键词 ROAD shaping endowed
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Grain Shape Genes:Shaping the Future of Rice Breeding 被引量:1
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作者 LU Xuedan LI Fan +4 位作者 XIAO Yunhua WANG Feng ZHANG Guilian DENG Huabing TANG Wenbang 《Rice science》 SCIE CSCD 2023年第5期379-404,共26页
The main goals of rice breeding nowadays include increasing yield,improving grain quality,and promoting complete mechanized production to save labor costs.Rice grain shape,specified by three dimensions,including grain... The main goals of rice breeding nowadays include increasing yield,improving grain quality,and promoting complete mechanized production to save labor costs.Rice grain shape,specified by three dimensions,including grain length,width and thickness,has a more precise meaning than grain size,contributing to grain appearance quality as well as grain weight and thus yield.Furthermore,the divergence of grain shape characters could be utilized in mechanical seed sorting in hybrid rice breeding systems,which has been succeeded in utilizing heterosis to achieve substantial increase in rice yield in the past decades.Several signaling pathways that regulate rice grain shape have been elucidated,including G protein signaling,ubiquitination-related pathway,mitogen-activated protein kinase signaling,phytohormone biosynthesis and signaling,micro RNA process,and some other transcriptional regulatory pathways and regulators.This review summarized the recent progress on molecular mechanisms underlying rice grain shape determination and the potential of major genes in future breeding applications. 展开更多
关键词 grain shape grain quality yield mechanization of seed sorting hybrid rice molecular function regulatory pathway
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Multiple Kalman filters model with shaping filter GPS real-time deformation analysis 被引量:6
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作者 李丽华 彭军还 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3674-3681,共8页
In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GP... In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GPS real-time deformation series with a high sampling rate contain coloured noise, the multiple Kalman filter model requires the white noise, and the multiple Kalman filters model is augmented by a shaping filter in order to reduce the colored noise; secondly, the multiple Kalman filters model with shaping filter can detect the deformation epoch in real-time and improve the quality of GPS measurements for the real-time deformation applications. Based on the comparisons of the applications in different GPS time series with different models, the advantages of the proposed model were illustrated. The proposed model can reduce the colored noise, detect the smaller changes, and improve the precision of the detected deformation epoch. 展开更多
关键词 multiple Kalman filters model Kalman filter shaping filter deformation detection
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Digitalization of inverting filter shaping circuit for nuclear pulse signals 被引量:7
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作者 Huai-Qiang Zhang Hong-Tao Shi +1 位作者 Zhuo-Dai Li Yu-Wen Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第9期16-24,共9页
In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a ... In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a pulse signal,they are widely used in processing nuclear pulse signals.In this study,the transfer functions of four types of inverting filter shaping circuits,namely the common inverting filter shaping,improved inverting filter shaping,multiple feedback low-pass filter shaping,and third-order multiple feedback low-pass filter shaping,in the Laplacian domain,are derived.We establish the numerical recursive function models and digitalize the four circuits,obtain the transfer functions in the Z domain,and analyze the filter performance and amplitude-frequency response characteristics in the frequency domain.Based on the actual nuclear pulse signal of the Si-PIN detector,we realize four types of inverting digital shaping.The results show that under the same shaping parameters,the common inverting digital shaping has better amplitude extraction characteristics,the third-order multiple feedback low-pass digital shaping has better noise suppression performance,and the multiple feedback digital shaping takes into account both pulse amplitude extraction and noise suppression performance. 展开更多
关键词 Nuclear pulse signal Inverting filter shaping circuit Digital shaping Amplitude-frequency response
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Driving Behavior Shaping Model in Road Traffic System 被引量:2
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作者 王武宏 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期331-336,共6页
In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analys... In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system. 展开更多
关键词 driving errors driving behavior shaping factors driving reliability and safety analysis road traffic safety
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A comparative study of optimization algorithms for wavefront shaping 被引量:3
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作者 Zahra Fayyaz Nafiseh Mohammadian +2 位作者 M.Reza Rahimi Tabar Rayyan Manwar Kamran(Mohammad)Avanaki 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第4期74-82,共9页
By manipulating the phase map of a wavefront of light using a spatial light modulator,the scattered light can be sharply focused on a specific target.Several iterative optimization algo-rithrns for obtaining the optim... By manipulating the phase map of a wavefront of light using a spatial light modulator,the scattered light can be sharply focused on a specific target.Several iterative optimization algo-rithrns for obtaining the optimumn phase map have been explored.However,there has not been a comparative study on the performance of these algorithms.In this paper,six optimization algorithms for wavefront shaping inchuding continuous sequential,partitioning algorithm,transmission matrix estimation method,particle swarm optimization,genetic algorithm(GA),and simulated annealing(SA)are discussed and compared based on their efficiency when introduced with various measurement noise levels. 展开更多
关键词 Wave front shaping algorithms OPTIMIZATION turbid media wavefront shaping
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Seismic attenuation compensation with spectral-shaping regularization
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作者 QiZhen Du WanYu Wang +1 位作者 WenHan Sun Li-Yun Fu 《Earth and Planetary Physics》 EI CSCD 2022年第3期259-274,共16页
Because of the viscoelasticity of the subsurface medium,seismic waves will inherently attenuate during propagation,which lowers the resolution of the acquired seismic records.Inverse-Q filtering,as a typical approach ... Because of the viscoelasticity of the subsurface medium,seismic waves will inherently attenuate during propagation,which lowers the resolution of the acquired seismic records.Inverse-Q filtering,as a typical approach to compensating for seismic attenuation,can efficiently recover high-resolution seismic data from attenuation.Whereas most efforts are focused on compensating for highfrequency energy and improving the stability of amplitude compensation by inverse-Q filtering,low-frequency leakage may occur as the high-frequency component is boosted.In this article,we propose a compensation scheme that promotes the preservation of lowfrequency energy in the seismic data.We constructed an adaptive shaping operator based on spectral-shaping regularization by tailoring the frequency spectra of the seismic data.We then performed inverse-Q filtering in an inversion scheme.This data-driven shaping operator can regularize and balance the spectral-energy distribution for the compensated records and can maintain the low-frequency ratio by constraining the overcompensation for high-frequency energy.Synthetic tests and applications on prestack common-reflectionpoint gathers indicated that the proposed method can preserve the relative energy of low-frequency components while fulfilling stable high-frequency compensation. 展开更多
关键词 seismic attenuation compensation spectral-shaping regularization data-driven shaping operator offset-related inverse-Q filter
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Numerical Simulation of Multi-track and Multi-layer Temperature Field on Laser Direct Metal Shaping 被引量:8
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作者 LONG Risheng~(1,2) LIU Weijun~1 (1.Advanced Manufacture Lab,Shenyang Institute of Automation,Shenyang 110016,China, 2.Graduate School,Chinese Academy of Sciences,Beijing 100039,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期1111-1116,共6页
To improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping(LDMS),it is of great significance to understand the distribution regularities of transient temperature field during LDMS proce... To improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping(LDMS),it is of great significance to understand the distribution regularities of transient temperature field during LDMS process.Based on the“el- ement birth and death”technique of finite element method,a three-dimensional multi-track and multi-layer model for the transient temperature field analysis of LDMS is developed by ANSYS Parametric Design Language(APDL)for the first time.In the fab- ricated modal,X-direction parallel reciprocating scanning paths is introduced.Using the same process parameters,the simulation results show good agreement with the microstructure features of samples which fabricated by LDMS. 展开更多
关键词 LASER DIRECT METAL shaping transient temperature field numerical simulation
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