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Effect of parameter setting and spectral normalization approach on study of matrix effect by laser induced breakdown spectroscopy of Ag–Zn binary composites 被引量:1
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作者 Harse SATTAR Liying SUN +3 位作者 Muhammad IMRAN Ran HAI Ding WU Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期155-166,共12页
The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical perfo... The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical performance of three different normalization methods, namely normalization with background, internal normalization and three point smoothing techniques at different parameter settings is studied for quantification of Ag and Zn by Laser induced breakdown spectroscopy(LIBS).The LIBS spectra of five known concentration of silver zinc binary composites have been investigated at various laser irradiances(LIs). Calibration curves for both Ag(I) line(4d^(10)5s^2S_(1/2)→4d^(10)5p^2P_(1/2) at 338.28 nm) and Zn(I) line(4s5s^3S_1→4s4p^3P_2 at 481.053 nm) have been determined at LI of 5.86?×?10^(10)W cm^(-2). Slopes of these calibration curves provide the valuation of matrix effect in the Ag–Zn composites. With careful sample preparation and normalization after smoothing at optimum parameter setting(OPS), the minimization of sample matrix effect has been successfully achieved. A good linearity has been obtained in Ag and Zn calibration curve at OPS when normalized the whole area of spectrum after smoothing and the obtained coefficients of determination values were R^2?=?0.995 and 0.998 closer to 1. The results of matrix effect have been further verified by analysis of plasma parameters. Both plasma parameters showed no change with varying concentration at OPS. However, at high concentration of Ag, the observed significant changes in both plasma parameters at common parameter setting PS-1 and PS-2 were the gesture of matrix effect. In our case, the better analytical results were obtained at smoothing function with optimized parameter setting that indicates it is more efficient than normalization with background and internal normalization method. 展开更多
关键词 Ag–Zn COMPOSITES laser induced BREAKDOWN spectroscopy optimum parameter setting SELF-ABSORPTION matrix EFFECT
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Application of MPSO technique to find optimal location and parameter setting of TCSC
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作者 王延鹏 蔡兴国 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期101-105,共5页
A new mothod was presented to find the optimal location and parameter setting of Thyristor Controlled Series Compensator (TCSC) to maxmize the transfer capability.Firstly the sensitivity of the transfer capability wit... A new mothod was presented to find the optimal location and parameter setting of Thyristor Controlled Series Compensator (TCSC) to maxmize the transfer capability.Firstly the sensitivity of the transfer capability with respect was described to the line's reactance was described to find the more sensitive lines for installing TCSC,however,the line which has the most sesitivity value is always not the best line for installing TCSC.For solving this problem,the more sensitive m lines were selected as the alternative line group of installing TCSC,and then modified particle swarm optimization (MPSO) was used to find out the optimal location and the optimal parameter settings of TCSC.Particle swarm optimization (PSO) algorithm can results premature convergence.For solving this problem,population entropy and cellular automata were introduced to it.Simulation results of IEEE 30-bus system proved the effectiveness of the method and its application values. 展开更多
关键词 TCSC optimal location and parameter settings modified particle swarm optimization continuation oower flow
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Automatic Optimization of Chirp Setting Parameters in Medical Ultrasound Contrast Imaging
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作者 Amira Zaylaa Sebastien Menigot +1 位作者 Jamal Charara Jean-Marc Girault 《Journal of Life Sciences》 2013年第6期592-598,共7页
Medical ultrasound contrast imaging is a powerful modality undergoing successive developments in the last decade to date Lately, pulse inversion has been used in both ultrasound tissue harmonic and contrast imaging. H... Medical ultrasound contrast imaging is a powerful modality undergoing successive developments in the last decade to date Lately, pulse inversion has been used in both ultrasound tissue harmonic and contrast imaging. However, there was a tradeoff between resolution and penetration. Chirp excitations partially solved the tradeoff, but the chirp setting parameters were not optimized. The present work proposes for the first time combining chirp inversion with ultrasound contrast imaging, with the motivation to improve the contrast, by automatically optimizing the setting parameters of chirp excitation, it is thus an optimal command problem. Linear chirps, 5 μm diameter microbubbles and gradient ascent algorithm were simulated to optimize the chirp setting parameters. Simulations exhibited a gain of 5 dB by automatic optimization of chirp inversion relative to pulse inversion. The automatic optimization process was quite fast. Combining chirp inversion with ultrasound contrast imaging led to a maximum backscattered power permitting high contrast outcomes and optimum parameters. 展开更多
关键词 Medical ultrasound contrast imaging chirp inversion chirp setting parameters automatic technique optimal command.
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Effects of transmitter-related parameter settings on ranging accuracy for IR-UWB systems
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作者 吴绍华 张钦宇 张乃通 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第1期51-57,共7页
For impulse radio ultra-wideband (IR-UWB) ranging systems,effects of the settings of transmitter-related parameters, which include the pulse shape, the bandwidth and the pulse repetition interval (PRI), on ranging acc... For impulse radio ultra-wideband (IR-UWB) ranging systems,effects of the settings of transmitter-related parameters, which include the pulse shape, the bandwidth and the pulse repetition interval (PRI), on ranging accuracy were studied through theoretical analysis and simulations. Both the match-filtering based coherent TOA estimation algorithm and the energy-detection based non-coherent algorithm were used during simulations. Results show that the pulse shape has the least effect on the ranging accuracy. Increasing the pulse bandwidth can improve the ranging performance, but the performance is hardly improved any more when the bandwidth is increased beyond a certain level. PRI should be set long enough to guarantee the accurate ranging, because when PRI is shorter than the maximum excess delay of the channel, the ranging accuracy will be deteriorated by inter-pulse interference. 展开更多
关键词 IR-UWB ranging TOA estimation algorithm parameter setting match-filtering energy-detection
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Phase-Based Optical Flow Method with Optimized Parameter Settings for Enhancing Displacement Measurement Adaptability
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作者 Zhaoxin Peng Menglian Liu +2 位作者 Zhiliang Wang Wei Liu Xian Wang 《Open Journal of Applied Sciences》 2024年第5期1165-1184,共20页
To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizi... To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizing parameter settings is proposed. The optimized parameters include the best measurement points of the Region of Interest (ROI) and the levels of pyramid filters. Additionally, to address the issue of updating reference frames in practical applications due to the difficulty in estimating the maximum effective measurement value, a mechanism for dynamically updating reference frames is introduced. Experimental results demonstrate that compared to representative image gradient-based displacement measurement methods, the proposed method exhibits higher measurement accuracy in engineering applications. This provides reliable data support for structural damage identification research based on vibration signals and is expected to broaden the engineering application prospects for structural health monitoring. 展开更多
关键词 Displacement Measurement Phase-Based Optical Flow Optimized parameter setting
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Effect of Heat-Setting on Structural Parameters and Mechanical Properties of PP Monofilament Hernia Patch
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作者 LIU Yuan-yuan CHEN Nan-liang 《Journal of Donghua University(English Edition)》 EI CAS 2014年第5期654-658,共5页
General surgery hernia is a common and frequently- occurring disease in the world. In the tension-free hernia repair surgery, polypropylene (PP) patch has been confirmed as the most popular surgical implants. In thi... General surgery hernia is a common and frequently- occurring disease in the world. In the tension-free hernia repair surgery, polypropylene (PP) patch has been confirmed as the most popular surgical implants. In this study, domestic medical PP monofilament was selected as raw material whose diameter was 0.15 mm, and the patch was knitted in the warp knitting machine of 12E gauge with one bar. Using the method of orthogonal experiment with three factors and three levels, the best heat-setting process of PP mesh was determined at the temperature of 130 ~C with 10 min under tension-free conditions. The relationship between heat-setting tension and performance of the patch was discussed. Patches with different porosity were prepared, and then structural parameters including density, thickness, porosity, and mechanical properties including tensile breaking strength, bursting strength, tearing strength, flexural rigidity and suture pulling out strength were tested and compared. The experimental results show that: the smaller of the patch's density, the higher of the porosity; other properties including density, thickness, bending stiffness, tensile breaking strength, bursting strength, tear strength, and suture pulling out strength reduce in varying degrees. This different degree of reduction is worth summarizing. 展开更多
关键词 hernia patch polypropylene (PP) porosity heat-settingtension structural parameters MECHANICAL properties
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Efficient Parameterization for Knowledge Graph Embedding Using Hierarchical Attention Network
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作者 Zhen-Yu Chen Feng-Chi Liu +2 位作者 Xin Wang Cheng-Hsiung Lee Ching-Sheng Lin 《Computers, Materials & Continua》 2025年第3期4287-4300,共14页
In the domain of knowledge graph embedding,conventional approaches typically transform entities and relations into continuous vector spaces.However,parameter efficiency becomes increasingly crucial when dealing with l... In the domain of knowledge graph embedding,conventional approaches typically transform entities and relations into continuous vector spaces.However,parameter efficiency becomes increasingly crucial when dealing with large-scale knowledge graphs that contain vast numbers of entities and relations.In particular,resource-intensive embeddings often lead to increased computational costs,and may limit scalability and adaptability in practical environ-ments,such as in low-resource settings or real-world applications.This paper explores an approach to knowledge graph representation learning that leverages small,reserved entities and relation sets for parameter-efficient embedding.We introduce a hierarchical attention network designed to refine and maximize the representational quality of embeddings by selectively focusing on these reserved sets,thereby reducing model complexity.Empirical assessments validate that our model achieves high performance on the benchmark dataset with fewer parameters and smaller embedding dimensions.The ablation studies further highlight the impact and contribution of each component in the proposed hierarchical attention structure. 展开更多
关键词 Knowledge graph embedding parameter efficiency representation learning reserved entity and relation sets hierarchical attention network
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Relativistic Correction on Neutrino Emission from Neutron Stars in Various Parameter Sets
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作者 Wen-Bo Ding Zhan-Qiang Qi +5 位作者 Jia-Wei Hou Geng Mi Tmurbagan Bao Zi Yu Guang-Zhou Liu En-Guang Zhao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第10期474-478,共5页
In the relativistic mean field theory and cooling theories,relativistic correction on neutrino emission from neutron stars in four typical nuclear parameter sets,GM1,GL85,GPS250 and GPS300 is studied.Results show that... In the relativistic mean field theory and cooling theories,relativistic correction on neutrino emission from neutron stars in four typical nuclear parameter sets,GM1,GL85,GPS250 and GPS300 is studied.Results show that relativistic effect makes the neutrino emissivity,neutrino luminosity and cooling rate lower,compared with the nonrelativistic case.And the influence of relativistic effect grows with the mass of the neutron star.GPS300 set leads to the biggest fall in neutrino emissivity,whereas GM1 set leads to the largest disparity in cooling rate caused by relativistic effect. 展开更多
关键词 neutron star neutrino emission relativistic correction parameter set
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Analysis on a Set of 12-parameter Rectangular Plate Element with High Accuracy
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作者 SHI Dong-yang WANG Cai-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期159-165,共7页
It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape f... It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape function space is nothing but the Adini's element's, which has nothing to do with the other high degree terms and leads to a new method for constructing the high accuracy plate elements. This fact has never been seen for other conventional and unconventional, conforming and nonconforming rectangular plate elements, such as Quasi-conforming elements, generalized conforming elements and other double set parameter finite elements. Moreover, such kind of rectangular elements can not be constructed by the conventional finite element methods. 展开更多
关键词 double set parameter element high accuracy Adini's shape function space geometric symmetry new method
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Sensitivity analysis for parameters of a monitoring system for steep slopes of open-pit mines 被引量:5
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作者 HAN Xue HE Man-chao ZHANG Bi 《Mining Science and Technology》 EI CAS 2009年第4期441-445,共5页
Monitoring the stability of steep slopes of open-pit mines is a major issue relating to production safety in mines.In order to determine the technical parameters of a new type of supervising system applied in monitori... Monitoring the stability of steep slopes of open-pit mines is a major issue relating to production safety in mines.In order to determine the technical parameters of a new type of supervising system applied in monitoring steep slopes of open-pit mines,the MSARMA method was used to establish analytical models for the monitoring system,given various parameter settings based on the description of mechanical monitoring principles.We used this sensitivity analysis to conclude that the setting of the most sensitive location of a mechanical monitoring system should be within a range of 1/5~1/2 of the lower part in a vertical direction of steep slopes,with a rational and feasible range of the dip angle setting between 0°~20°.Given the analytical results of our on-site experiments,we have shown that the parameters determined reflect the stability of steep slopes accurately and effectively.These conclusions provide a basis for the application of a new type of steep slope stability monitoring technology in open-pit mines. 展开更多
关键词 open-pit mine steep slope monitoring system setting parameter analysis
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Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam 被引量:8
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作者 张小刚 宋玉普 吴智敏 《Transactions of Tianjin University》 EI CAS 2005年第1期59-65,共7页
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture t... By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice. 展开更多
关键词 roller-compacted concrete (RCC) arch dam induced crack double-K fracture parameters equivalent strength calculation model optimizing setting
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A Model of Spray Tool and a Parameter Optimization Method for Spraying Path Planning 被引量:1
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作者 Ru-Xiang Hua Wei Zou +2 位作者 Guo-Dong Chen Hong-Xuan Ma Wei Zhang 《International Journal of Automation and computing》 EI CSCD 2021年第6期1017-1031,共15页
The digital camouflage spraying of special vehicles carried out by robots can greatly improve the spraying efficiency, spraying quality, and rapid adaptability to personalized patterns. The selection of spray tool and... The digital camouflage spraying of special vehicles carried out by robots can greatly improve the spraying efficiency, spraying quality, and rapid adaptability to personalized patterns. The selection of spray tool and the accuracy of the adopted mathematical spray tool model has a great impact on the effectiveness of spray path planning and spraying quality. Since traditional conical spray tool models are not suitable for spraying rectangular digital camouflage, according to the characteristics of digital camouflage, the coating thickness cumulative distribution model of strip nozzle spray tool for 2 D plane spraying and 3 D surface spraying is derived, and its validity is verified by simulation. Based on the accumulation velocity model of the coating thickness(AVCT) on the curved surface and aiming at spraying path planning within the same surface and different surfaces, a path parameter optimization method based on coating uniformity evaluation of adjacent path overlapping area is proposed. Combined with the vehicle surface model, parameters such as path interval, spray tool angle and spray tool motion velocity can be calculated in real-time to ensure uniform coating. Based on the known local three-dimensional model of vehicle surface and the comprehensive spraying simulation, the validity of the purposed models: the coating thickness on the adjacent path area(CTAPA), the coating thickness on the intersection of two surfaces(CTITS), the coating thickness on the intersection of a plane and a surface(CTIPS), and the optimization method of path parameters are verified. The results show that compared with the traditional spray tool, the strip nozzle can better ensure the uniformity of the coating thickness of digital camouflage spray. Finally, according to a practical spraying experiment, the results prove that the proposed models not only are effective but also meet the practical industrial requirements and are of great practical value. 展开更多
关键词 Digital camouflage spraying robot path optimization parameter setting coating thickness uniformity
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An approach to optimize the settings of actuated signals
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作者 Xinguo JIANG Yanjun QIU Sheng RUAN 《Journal of Modern Transportation》 2011年第1期68-74,共7页
Traffic-actuated signal employs relatively complex control logic to regulate traffic flow. Introduction of control variables into the traffic-actuated system contributes to system operational flexibility and complexit... Traffic-actuated signal employs relatively complex control logic to regulate traffic flow. Introduction of control variables into the traffic-actuated system contributes to system operational flexibility and complexity, and also complicates the system with uncertainties. The paper proposes two tentative methods to optimize the actuated signal parameters: basic requirements of controller parameters and analytical model, and macroscopic computer simulation. It is concluded that when the actuated signal operates within the volume/capacity range of 0.4 to 0.6, it will create the most significant benefits; the research suggests that minimum green time in the main street shall be set long enough to meet the required demand, preferably at the 60% of the main street capacity. In order to ensure less control delay in a semi-actuated intersection, relatively small values of vehicle extension (e.g., 2.5 s) and maximum green time are recommended to be assigned to the less important street. 展开更多
关键词 actuated signals OPTIMIZATION parameter settings computer simulation
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Reconstruction of protoliths of metamorphic rocks and tectonic setting of Wolegen Group
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作者 Lizhi LUO Wei JIN Changqing ZHENG Xianli YANG 《Global Geology》 2007年第1期105-109,共5页
Parametamorphic rocks from Arong County in southeastern Inner Mongolia- Daxinganling district are regarded as Proterozoic in age, belonging to the Wolegen Group and composed of volcanoclastic and sand- stone in origin... Parametamorphic rocks from Arong County in southeastern Inner Mongolia- Daxinganling district are regarded as Proterozoic in age, belonging to the Wolegen Group and composed of volcanoclastic and sand- stone in origin, and have been disputed in tectonic setting. Because of the stability in metamorphism, the rare earth elements indicate the features of their protoliths. The authors integrated the petrologic methods with the geochemical parameters which include ЕREE, ЕLREE/NHREE, δCe, δEu, La/Yb, Sm/Nd, Th/Sc and the standard values of chondrite. The results show that the protoliths of Wolengen Group may be a group of volcanoclastic and continental margin clastic rocks, and their tectonic setting is the continent island arc. 展开更多
关键词 Wolegen Group metamorphic volcanoclastic rocks metasandstone geochemical parameters RECONSTRUCTION protoliths tectonic setting
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基于PARAMETER_REG的无线参数设置规范与位置更新探讨
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作者 谢和忠 《科技创新与应用》 2020年第4期19-21,共3页
为提高部分智能机的寻呼成功率,在标准协议之外增加一个Feature,待机状态从一个小区(PARAMETER_REG=1)切换到另一个小区(PARAMETER_REG=0),增加发送一次基于时间位置更新,但频繁位置更新增大手机功耗及运营商的网络设备负荷,也容易发生... 为提高部分智能机的寻呼成功率,在标准协议之外增加一个Feature,待机状态从一个小区(PARAMETER_REG=1)切换到另一个小区(PARAMETER_REG=0),增加发送一次基于时间位置更新,但频繁位置更新增大手机功耗及运营商的网络设备负荷,也容易发生信令碰撞影响终端被叫接通率。为规避部分手机位置更新频繁问题,建议全网PARAMETER_REG统一设置为1(开启),当特定参数(SCI、终端等级标志等)发生变化时,触发参数变化登记。 展开更多
关键词 parameter_REG 无线参数设置 位置更新
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Set Cover和Hitting Set问题的研究进展 被引量:2
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作者 李绍华 王建新 +1 位作者 冯启龙 陈建二 《计算机科学》 CSCD 北大核心 2009年第10期1-4,15,共5页
Set Cover和Hitting Set问题是两个重要的W[2]完全问题。Set Cover问题在大规模集成电路设备的测试和人员调度等领域有着广泛的应用,Hitting Set问题在生物计算等领域有着重要的应用。在引入参数计算和复杂性理论后,Set Cover和Hitting ... Set Cover和Hitting Set问题是两个重要的W[2]完全问题。Set Cover问题在大规模集成电路设备的测试和人员调度等领域有着广泛的应用,Hitting Set问题在生物计算等领域有着重要的应用。在引入参数计算和复杂性理论后,Set Cover和Hitting Set问题再次成为研究的热点。首先介绍Set Cover和Hitting Set的各种分类问题及其定义,并对各种分类问题的计算复杂性和相关算法的研究进展加以分析总结,给出(k,h)-Set Cover和(k,d)-Set Cover问题的复杂性证明。最后总结全文并提出进一步研究的方向。 展开更多
关键词 集合覆盖 撞碰集 近似算法 固定参数可解
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固定界面Level Set方法在爆轰波阵面传播中的应用 被引量:2
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作者 张莉 吴开腾 《兵工学报》 EI CAS CSCD 北大核心 2019年第10期2080-2087,共8页
针对重新初始化造成的界面位置偏离问题,提出一种固定界面LevelSet方法。该方法的基本思想是在重新初始化相邻两次迭代过程中,通过构建保持界面不动满足的条件,从而推导出光滑参数的计算公式。与传统LevelSet方法相比较,固定界面LevelSe... 针对重新初始化造成的界面位置偏离问题,提出一种固定界面LevelSet方法。该方法的基本思想是在重新初始化相邻两次迭代过程中,通过构建保持界面不动满足的条件,从而推导出光滑参数的计算公式。与传统LevelSet方法相比较,固定界面LevelSet方法将固定的光滑参数修正为变化的光滑参数。数值模拟结果表明:固定界面LevelSet方法在重新初始化过程中能够很好地固定界面位置,从而提高LevelSet方法的质量守恒性;固定界面LevelSet方法能够有效地避免由于误差累积导致的爆轰波阵面偏离现象,具有较高的计算精度和分辨率,适用于求解爆轰波阵面传播问题。 展开更多
关键词 Levelset方法 固定界面 光滑参数 爆轰波阵面 传播
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四参数随机生长法参数对多孔介质建模的影响
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作者 李明 《岩土力学》 北大核心 2026年第1期349-358,共10页
四参数随机生长(quartet-parameter structure generation set,简称QSGS)法是目前较常用的多孔介质建模算法,多孔介质的分形维数D和孔隙自相关距离λ是评价建模效果的两个重要指标,目前缺乏关于QSGS法建模参数与多孔介质分形维数、孔隙... 四参数随机生长(quartet-parameter structure generation set,简称QSGS)法是目前较常用的多孔介质建模算法,多孔介质的分形维数D和孔隙自相关距离λ是评价建模效果的两个重要指标,目前缺乏关于QSGS法建模参数与多孔介质分形维数、孔隙自相关距离间关系的研究。首先,提出了一种生长核分布概率归一化处理方法,在此基础上设计了一套不同网格尺寸N、孔隙率φ、归一化生长核分布概率P_(η)组合下多孔介质建模的数值模拟方案;然后,基于数值模拟结果分析了D、λ随建模参数N、φ、P_(η)的变化规律,并基于正交试验分析了建模参数的敏感性;最后,构建了建模参数N、φ、P_(η)与D、λ的拟合关系。结果显示,建模参数N、φ、P_(η)对D均有一定程度的影响,且φ的影响最大,P_(η)的影响其次,N的影响最小;λ的最主要影响因素是P_(η),其他参数的影响较小。所构建的多元回归拟合模型精度较高,可以用于指导QSGS法的建模。 展开更多
关键词 四参数随机生长法 分形维数 自相关距离 多元回归拟合
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超声探伤仪发射参数校准结果影响因素分析
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作者 薛峰 《无损检测》 2026年第1期87-92,共6页
超声探伤仪发射参数的校准是确保检测结果准确性的关键环节,但其校准结果受多种因素影响。基于国际标准(ISO 22232-1:2020,EN 12668-1:2010)和国内标准(GB/T 27664.1-2011,JJG 746-2024),分析了发射参数校准中的主要误差来源。分析发现... 超声探伤仪发射参数的校准是确保检测结果准确性的关键环节,但其校准结果受多种因素影响。基于国际标准(ISO 22232-1:2020,EN 12668-1:2010)和国内标准(GB/T 27664.1-2011,JJG 746-2024),分析了发射参数校准中的主要误差来源。分析发现,示波器设置(如脉冲宽度测量位置)、负载特性(如阻抗稳定性)以及标准差异对校准结果有显著影响。通过对比不同负载在高频下的阻抗特性及实际测试数据,验证了绕线电阻等负载在高频场景中的不适用性。此外,操作规范(如示波器探头校准)和线缆选择也对测量精度至关重要。研究结果为超声探伤仪发射参数的校准提供了优化建议,强调了严格遵循标准和选用合适设备的重要性。 展开更多
关键词 超声探伤仪 发射参数校准 误差分析 示波器设置 负载特性 标准差异
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