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Gray code based gradient-free optimization algorithm for parameterized quantum circuit
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作者 张安琪 武春辉 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期189-194,共6页
A Gray code based gradient-free optimization(GCO)algorithm is proposed to update the parameters of parameterized quantum circuits(PQCs)in this work.Each parameter of PQCs is encoded as a binary string,named as a gene,... A Gray code based gradient-free optimization(GCO)algorithm is proposed to update the parameters of parameterized quantum circuits(PQCs)in this work.Each parameter of PQCs is encoded as a binary string,named as a gene,and a genetic-based method is adopted to select the offsprings.The individuals in the offspring are decoded in Gray code way to keep Hamming distance,and then are evaluated to obtain the best one with the lowest cost value in each iteration.The algorithm is performed iteratively for all parameters one by one until the cost value satisfies the stop condition or the number of iterations is reached.The GCO algorithm is demonstrated for classification tasks in Iris and MNIST datasets,and their performance are compared by those with the Bayesian optimization algorithm and binary code based optimization algorithm.The simulation results show that the GCO algorithm can reach high accuracies steadily for quantum classification tasks.Importantly,the GCO algorithm has a robust performance in the noise environment. 展开更多
关键词 gradient-free optimization Gray code genetic-based method
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Totally Coded Method for Signal Flow Graph Algorithm 被引量:2
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作者 徐静波 周美华 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期63-68,共6页
After a code-table has been established by means of node association information from signal flow graph, the totally coded method (TCM) is applied merely in the domain of code operation beyond any figure-earching algo... After a code-table has been established by means of node association information from signal flow graph, the totally coded method (TCM) is applied merely in the domain of code operation beyond any figure-earching algorithm. The code-series (CS) have the holo-information nature, so that both the content and the sign of each gain-term can be determined via the coded method. The principle of this method is simple and it is suited for computer programming. The capability of the computer-aided analysis for switched current network (SIN) can be enhanced. 展开更多
关键词 SIGNAL FLOW graph algorithm codeD method SIN.
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Open-Source Codes of Topology Optimization: A Summary for Beginners to Start Their Research 被引量:2
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作者 Yingjun Wang Xinqing Li +1 位作者 Kai Long Peng Wei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期1-34,共34页
Topology optimization(TO),a numerical technique to find the optimalmaterial layoutwith a given design domain,has attracted interest from researchers in the field of structural optimization in recent years.For beginner... Topology optimization(TO),a numerical technique to find the optimalmaterial layoutwith a given design domain,has attracted interest from researchers in the field of structural optimization in recent years.For beginners,opensource codes are undoubtedly the best alternative to learning TO,which can elaborate the implementation of a method in detail and easily engage more people to employ and extend the method.In this paper,we present a summary of various open-source codes and related literature on TO methods,including solid isotropic material with penalization(SIMP),evolutionary method,level set method(LSM),moving morphable components/voids(MMC/MMV)methods,multiscale topology optimization method,etc.Simultaneously,we classify the codes into five levels,fromeasy to difficult,depending on their difficulty,so that beginners can get started and understand the form of code implementation more quickly. 展开更多
关键词 Topology optimization open-source code optimization methods code classification BEGINNERS
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The Research on Methodology for Material Code Standardization in the Implementation of MRP-Ⅱ
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作者 孙虞 《Journal of Southeast University(English Edition)》 EI CAS 1996年第2期13-18,共6页
This paper analyses the current common problems of material code standardization in the implementation of MRP Ⅱ, and puts forward the basic ideas and methods for solving the problems, which has some reference value ... This paper analyses the current common problems of material code standardization in the implementation of MRP Ⅱ, and puts forward the basic ideas and methods for solving the problems, which has some reference value for the popularization of application o 展开更多
关键词 CODING standard methods
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Programming Logic Modeling and Cross-Program Defect Detection Method for Object-Oriented Code
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作者 Yan Liu Wenyuan Fang +2 位作者 Qiang Wei Yuan Zhao Liang Wang 《Computers, Materials & Continua》 SCIE EI 2020年第7期273-295,共23页
Code defects can lead to software vulnerability and even produce vulnerability risks.Existing research shows that the code detection technology with text analysis can judge whether object-oriented code files are defec... Code defects can lead to software vulnerability and even produce vulnerability risks.Existing research shows that the code detection technology with text analysis can judge whether object-oriented code files are defective to some extent.However,these detection techniques are mainly based on text features and have weak detection capabilities across programs.Compared with the uncertainty of the code and text caused by the developer’s personalization,the programming language has a stricter logical specification,which reflects the rules and requirements of the language itself and the developer’s potential way of thinking.This article replaces text analysis with programming logic modeling,breaks through the limitation of code text analysis solely relying on the probability of sentence/word occurrence in the code,and proposes an object-oriented language programming logic construction method based on method constraint relationships,selecting features through hypothesis testing ideas,and construct support vector machine classifier to detect class files with defects and reduce the impact of personalized programming on detection methods.In the experiment,some representative Android applications were selected to test and compare the proposed methods.In terms of the accuracy of code defect detection,through cross validation,the proposed method and the existing leading methods all reach an average of more than 90%.In the aspect of cross program detection,the method proposed in this paper is superior to the other two leading methods in accuracy,recall and F1 value. 展开更多
关键词 method constraint relationship programming logic code defect hypothesis test
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A Codebook Design Method for Robust VQ-Based Face Recognition Algorithm
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作者 Qiu Chen Koji Kotani +1 位作者 Feifei Lee Tadahiro Ohmi 《Journal of Software Engineering and Applications》 2010年第2期119-124,共6页
In this paper, we present a theoretical codebook design method for VQ-based fast face recognition algorithm to im-prove recognition accuracy. Based on the systematic analysis and classification of code patterns, first... In this paper, we present a theoretical codebook design method for VQ-based fast face recognition algorithm to im-prove recognition accuracy. Based on the systematic analysis and classification of code patterns, firstly we theoretically create a systematically organized codebook. Combined with another codebook created by Kohonen’s Self-Organizing Maps (SOM) method, an optimized codebook consisted of 2×2 codevectors for facial images is generated. Experimental results show face recognition using such a codebook is more efficient than the codebook consisted of 4×4 codevector used in conventional algorithm. The highest average recognition rate of 98.6% is obtained for 40 persons’ 400 images of publicly available face database of AT&T Laboratories Cambridge containing variations in lighting, posing, and expressions. A table look-up (TLU) method is also proposed for the speed up of the recognition processing. By applying this method in the quantization step, the total recognition processing time achieves only 28 msec, enabling real-time face recognition. 展开更多
关键词 FACE Recognition Vector QUANTIZATION (VQ) codeBOOK Design code Classification HISTOGRAM method
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On the Computing of the Minimum Distance of Linear Block Codes by Heuristic Methods
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作者 Mohamed Askali Ahmed Azouaoui +1 位作者 Said Nouh Mostafa Belkasmi 《International Journal of Communications, Network and System Sciences》 2012年第11期774-784,共11页
The evaluation of the minimum distance of linear block codes remains an open problem in coding theory, and it is not easy to determine its true value by classical methods, for this reason the problem has been solved i... The evaluation of the minimum distance of linear block codes remains an open problem in coding theory, and it is not easy to determine its true value by classical methods, for this reason the problem has been solved in the literature with heuristic techniques such as genetic algorithms and local search algorithms. In this paper we propose two approaches to attack the hardness of this problem. The first approach is based on genetic algorithms and it yield to good results comparing to another work based also on genetic algorithms. The second approach is based on a new randomized algorithm which we call 'Multiple Impulse Method (MIM)', where the principle is to search codewords locally around the all-zero codeword perturbed by a minimum level of noise, anticipating that the resultant nearest nonzero codewords will most likely contain the minimum Hamming-weight codeword whose Hamming weight is equal to the minimum distance of the linear code. 展开更多
关键词 Minimum Distance Error Impulse method Heuristic methods Genetic Algorithms NP-HARDNESS Linear Error Correcting codes BCH codes QR codes Double Circulant codes
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GOAT:a simulation code for high-intensity beams
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作者 Lei Wang Jian-Cheng Yang +1 位作者 Ming-Xuan Chang Fu Ma 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期163-182,共20页
A simulation code,GOAT,is developed to simulate single-bunch intensity-dependent effects and their interplay in the proton ring of the Electron-Ion Collider in China(EicC)project.GOAT is a scalable and portable macrop... A simulation code,GOAT,is developed to simulate single-bunch intensity-dependent effects and their interplay in the proton ring of the Electron-Ion Collider in China(EicC)project.GOAT is a scalable and portable macroparticle tracking code written in Python and coded by object-oriented programming technology.It allows for transverse and longitudinal tracking,including impedance,space charge effect,electron cloud effect,and beam-beam interaction.In this paper,physical models and numerical approaches for the four types of high-intensity effects,together with the benchmark results obtained through other simulation codes or theories,are presented and discussed.In addition,a numerical application of the cross-talk simulation between the beam-beam interaction and transverse impedance is shown,and a dipole instability is observed below the respective instability threshold.Different mitigation measures implemented in the code are used to suppress the instability.The flexibility,completeness,and advancement demonstrate that GOAT is a powerful tool for beam dynamics studies in the EicC project or other high-intensity accelerators. 展开更多
关键词 code development Numerical methods Beam dynamics High-intensity effects
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Resin Matrix/Fiber Reinforced Composite Material, Ⅱ: Method of Solution and Computer Code
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作者 李辰砂 Jiao Caishan +3 位作者 Liu Ying Wang Zhengping Wang Hongjie Cao Maosheng 《High Technology Letters》 EI CAS 2003年第3期71-74,共4页
According to a mathematical model which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composites, t... According to a mathematical model which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composites, the solution method to the model is made and a computer code is developed, which for flat-plate composites cured by a specified cure cycle, provides the variation of temperature distribution, the cure reaction process in the resin, the resin flow and fibers stress inside the composite, the void variation and the residual stress distribution. 展开更多
关键词 树脂基/光纤增强复合材料 数学模型 制备方法 解题方法 计算机代码 复合材料层压板
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Hierarchical Symbolic Analysis of Large Analog Circuits with Totally Coded Method
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作者 徐静波 《Journal of Donghua University(English Edition)》 EI CAS 2006年第2期59-62,共4页
Symbolic analysis has many applications in the design of analog circuits. Existing approaches rely on two forms of symbolic-expression representation: expanded sum-of-product form and arbitrarily nested form. Expanded... Symbolic analysis has many applications in the design of analog circuits. Existing approaches rely on two forms of symbolic-expression representation: expanded sum-of-product form and arbitrarily nested form. Expanded form suffers the problem that the number of product terms grows exponentially with the size of a circuit. Nested form is neither canonical nor amenable to symbolic manipulation. In this paper, we present a new approach to exact and canonical symbolic analysis by exploiting the sparsity and sharing of product terms. This algorithm, called totally coded method (TCM), consists of representing the symbolic determinant of a circuit matrix by code series and performing symbolic analysis by code manipulation. We describe an efficient code-ordering heuristic and prove that it is optimum for ladder-structured circuits. For practical analog circuits, TCM not only covers all advantages of the algorithm via determinant decision diagrams (DDD) but is more simple and efficient than DDD method. 展开更多
关键词 相似体综合回路 象征分析 回路模拟 象征矩阵行列式 完全编码法
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正交-响应面法在PBM细观参数标定中的应用
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作者 张慧梅 马志敏 +1 位作者 陈世官 王赋宇 《水资源与水工程学报》 CSCD 北大核心 2024年第2期183-191,共9页
数值模拟作为研究岩石力学特性、再现细观裂纹演化的主要途径,已受到大量关注。现有的数值模拟参数标定方法主要为试错法及正交试验法,但二者都未能充分考虑细观参数交互作用的影响,模拟精度欠佳且宏观破坏形态与室内试验存在较大差异... 数值模拟作为研究岩石力学特性、再现细观裂纹演化的主要途径,已受到大量关注。现有的数值模拟参数标定方法主要为试错法及正交试验法,但二者都未能充分考虑细观参数交互作用的影响,模拟精度欠佳且宏观破坏形态与室内试验存在较大差异。因此,采用正交-响应面法相结合的数值分析方法,首先通过正交试验筛选出具有显著影响的平行黏结模型(PBM)细观参数,其次应用响应面法(RSM)研究其交互作用对模型试样宏观参量的影响规律,最后结合岩石宏观破坏形态提出一套PBM参数标定流程。结果表明:有效模量E*与刚度比k n/k s对弹性模量E影响显著;k n/k s、接触摩擦系数μ、最小颗粒半径R_(min)对泊松比ν影响显著;黏聚力c与法向黏结强度σc及其交互作用对单轴抗压强度UCS影响显著,应用响应面法计算分析得出的细观参数的模拟值与试验值误差绝对值小于7%,且二者应力应变曲线力学特征相似,宏观破坏形态相同,证明所提出的PBM细观参数标定流程具备科学性和可靠性。 展开更多
关键词 细观参数标定 正交-响应面法 平行黏结模型 二维颗粒流程序(PFC^(2D))
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论作为数字行政执法方式的行政行为码
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作者 喻少如 鲜翰林 《北京理工大学学报(社会科学版)》 北大核心 2024年第4期118-128,共11页
数字信息技术与行政权力的融合为以法治为中心的政府治理带来挑战,而行政行为码作为数字行政执法方式的应用是数治与法治结合的重要体现,并蕴含着整体智治下对行政执法体制一体化塑造的制度逻辑、行政自制论对数字赋能与赋权关系重塑的... 数字信息技术与行政权力的融合为以法治为中心的政府治理带来挑战,而行政行为码作为数字行政执法方式的应用是数治与法治结合的重要体现,并蕴含着整体智治下对行政执法体制一体化塑造的制度逻辑、行政自制论对数字赋能与赋权关系重塑的理论逻辑以及行政效能对行政执法全流程覆盖的实践逻辑。行政行为码以统一赋码、一码关联、一码查询与一码追踪的实践运行机理,兼具政府信息公开与政府数据开放的法律性质,也为拓展应用奠定了理论基础。与此同时作为数字新兴执法方式的行政行为码由于规制理念的不明确、规则体系不健全以及功能应用程度不足,限制其应用场景与空间。在未来,行政行为码应从理念更新、规范控制和功能拓展三个方面进行塑形,推动行政行为码的功能实现与广泛应用。 展开更多
关键词 数字行政执法方式 行政行为码 行政执法体制 行政执法一体化 政府数据开放
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融合改进YOLOv7与UNet的编码点定位方法
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作者 刘升 古丽巴哈尔·托乎提 +1 位作者 补生来 买买提明·艾尼 《国外电子测量技术》 2024年第5期9-17,共9页
针对编码点的定位存在误检率高和精准度差的问题,提出了一种融合改进YOLOv7与UNet的圆形编码点定位方法。第1阶段使用改进的YOLOv7检测编码点的位置,改进的YOLOv7首先将DCN-v2可变形卷积引入ELAN模块,提升特征提取能力;其次把卷积块注... 针对编码点的定位存在误检率高和精准度差的问题,提出了一种融合改进YOLOv7与UNet的圆形编码点定位方法。第1阶段使用改进的YOLOv7检测编码点的位置,改进的YOLOv7首先将DCN-v2可变形卷积引入ELAN模块,提升特征提取能力;其次把卷积块注意力模块(CBAM)机制嵌入骨干网络使网络更关注目标特征;然后使用Focal-EIoU Loss提高收敛速度;最后构建OD-Cat模块替换ConCat模块以提升网络检测精度。提取出每个圆形编码点的ROI后,第2阶段通过UNet分割出编码点的中心轮廓后,使用最小二乘法拟合出编码点的中心。实验结果表明,改进后的模型比原YOLOv7的精确率提高了6.33%,平均精度均值(mAP)提升了5.76%;提出的定位方法验证了在噪声、亮度不足或曝光等复杂环境下可以准确定位出编码点的中心椭圆轮廓,在实际工业视觉测量中具备鲁棒性。 展开更多
关键词 编码点识别 深度学习 中心定位 YOLOv7 UNet 最小二乘法
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基于一步法的重反射层反应堆启动物理试验控制棒价值校核计算研究
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作者 李志峰 李帆 +3 位作者 赵常有 刘宙宇 朱宇翔 许怀金 《现代应用物理》 2024年第1期88-91,共4页
由于重反射层可减低中子泄漏从而提升中子经济性,因此某些大型先进压水堆采用重反射层减少临界尺寸来优化空间布局。由于重反射层与以往常用的围板水反射层差异较大,采用传统的两步法物理计算程序获得重反射层反应堆的精确中子学参数存... 由于重反射层可减低中子泄漏从而提升中子经济性,因此某些大型先进压水堆采用重反射层减少临界尺寸来优化空间布局。由于重反射层与以往常用的围板水反射层差异较大,采用传统的两步法物理计算程序获得重反射层反应堆的精确中子学参数存在一定的难度,因此使用先进的一步法物理计算程序对重反射层反应堆启动物理试验控制棒价值展开了计算,计算结果表明,确定论一步法程序NECP-X计算结果与蒙特卡罗参考值吻合良好。 展开更多
关键词 一步法 NECP-X程序 重反射层 控制棒价值
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四川某铜矿选冶渣综合理化特性及环境污染特性评价
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作者 张维 傅开彬 +4 位作者 王磊 谌书 姚俊 廖飞 魏浪 《环境化学》 CAS CSCD 北大核心 2024年第2期475-486,共12页
针对铜矿选冶渣组成复杂、环境特性不清和治理修复难度大等问题,采用矿物解离分析仪(MLA)、X射线光电子能谱仪(XPS)和同步热分析仪-傅里叶变换红外气相色谱质谱联用仪(STA-FTIR-GCMS)等分析测试仪器研究铜矿选冶渣的综合理化特性;运用... 针对铜矿选冶渣组成复杂、环境特性不清和治理修复难度大等问题,采用矿物解离分析仪(MLA)、X射线光电子能谱仪(XPS)和同步热分析仪-傅里叶变换红外气相色谱质谱联用仪(STA-FTIR-GCMS)等分析测试仪器研究铜矿选冶渣的综合理化特性;运用毒性浸出程序(TCLP)、改进的三步提取(BCR)、风险评估编码(RAC)和次生相与原生相比值(RSP)等方法研究铜矿选冶渣的环境污染特性.结果表明,铜矿选冶渣多呈团聚状,体积平均粒径为54.18μm,主要含铁橄榄石(75.33%)、磁铁矿(12.15%)、黑云母等物相.硫酸硝酸法测得的铜矿选冶渣Cr、Cu、Zn和Pb浓度未超过《危险废物鉴别标准浸出毒性鉴别》规定的危废限值,该铜矿选冶渣为一类一般工业固体废物.RAC法和RSP法评价结果表明,Cu是铜矿选冶渣的主要防治对象,Fe、Zn、Pb是铜矿选冶渣的次要防治对象.研究结果为铜矿选冶渣的安全处理和处置提供了基础数据. 展开更多
关键词 铜矿选冶渣 综合理化特性 环境污染特性 风险评估编码法(RAC) 次生相与原生相比值法(RSP)
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基于标签信息流的变电站电缆走向识别方法
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作者 张淞珲 马超俊 +3 位作者 徐盈盈 李红斌 张荣浩 李志民 《电测与仪表》 北大核心 2024年第6期167-172,180,共7页
电缆走向识别是电缆检修和施工中的重要一环,其识别的准确性直接影响人身和设备的安全。文章提出了一种基于标签信息流的变电站电缆走向识别方法,依据预定区域内变电站数量确定各变电站的标签码,将调制后包含变电站信息的标签信号通过... 电缆走向识别是电缆检修和施工中的重要一环,其识别的准确性直接影响人身和设备的安全。文章提出了一种基于标签信息流的变电站电缆走向识别方法,依据预定区域内变电站数量确定各变电站的标签码,将调制后包含变电站信息的标签信号通过各变电站接地网注入到出线电缆的屏蔽层上进行传输,在待测电缆侧检测信号后,将各变电站注入的标签信号与检测信号作相关运算,相关结果峰值最高的变电站即为待测电缆首尾所连接的变电站,从而在无需知晓电缆首尾连接归属的情况下实现电缆的走向识别。实验测试结果验证了基于标签信息流的变电站电缆走向识别方法的准确性和高效性。 展开更多
关键词 电缆在线识别 注入法 CDMA WALSH码
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美国门诊预付费系统支付方式研究及启示
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作者 李佳明 王锐 +2 位作者 丁锦希 葛梦茹 李伟 《卫生经济研究》 北大核心 2024年第4期76-80,共5页
目的:梳理美国门诊预付费系统(APC)的发展历程、分组方案及付费方式,为我国探索门诊医保支付方式改革提供参考。方法:基于文献研究,系统总结美国APC的主要措施与特点。结果:美国APC以医疗保健通用程序编码系统为基础,基于临床、资源消... 目的:梳理美国门诊预付费系统(APC)的发展历程、分组方案及付费方式,为我国探索门诊医保支付方式改革提供参考。方法:基于文献研究,系统总结美国APC的主要措施与特点。结果:美国APC以医疗保健通用程序编码系统为基础,基于临床、资源消耗相似原则及成本二倍规则,对门诊医疗服务项目进行分组,考虑门诊医疗服务特征形成多样化支付单元。结论:我国可借鉴美国APC,建立门诊预付费制度,需考虑门诊医疗服务特点合理设计支付政策,完善门诊医疗服务编码系统,兼顾创新技术发展需求,并做好不同支付方式之间的统筹协调工作。 展开更多
关键词 门诊预付费系统 医保支付方式 门诊医疗服务 医疗服务编码
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一种消除周期性毛刺相位误差的互补格雷码双N步相移法
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作者 韩叔桓 杨延西 +1 位作者 张新雨 李昕杰 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第3期198-205,共8页
互补格雷码双N步相移法因其具有鲁棒性好、检测精度高等特点在条纹投影轮廓术领域成为研究热点。然而,传统互补格雷码双N步相移法存在检测效率低以及未消除周期性毛刺相位误差的问题。针对这些问题,本文对传统互补格雷码双N步相移法进... 互补格雷码双N步相移法因其具有鲁棒性好、检测精度高等特点在条纹投影轮廓术领域成为研究热点。然而,传统互补格雷码双N步相移法存在检测效率低以及未消除周期性毛刺相位误差的问题。针对这些问题,本文对传统互补格雷码双N步相移法进行改进消除周期性毛刺相位误差,首先通过相机捕获形变条纹图像并计算出两组截断相位,然后利用两组截断相位的相关性消除检测数据中的相位差、周期性毛刺相位误差,再对两组截断相位进行融合,最后通过互补格雷码相位展开法对融合后的截断相位进行相位展开。实验得出本文方法在检测效率不变的情况下,能有效消除周期性毛刺相位误差,得到高精度展开相位,相比于未消除周期性毛刺相位误差的互补格雷码双N步相移法,本文检测方法精度提高了约24.57%,相比于互补格雷码N步相移法,本文检测方法精度提高了约6.29%。 展开更多
关键词 双N步相移法 展开相位 周期性毛刺相位误差 互补格雷码
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果园作业平台车架耐久性研究
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作者 刘佳奇 邱绪云 +1 位作者 高琦 宋裕民 《中国农机化学报》 北大核心 2024年第1期160-168,共9页
针对农用机械作业工况复杂、受多种外力、对结构件寿命影响较大等问题,以果园作业平台车架为研究对象,编制车架加速载荷谱,分析车架耐久性。采用有限元分析方法,对车架进行力学分析并选取关键载荷测点,建立果园作业平台多体动力学模型... 针对农用机械作业工况复杂、受多种外力、对结构件寿命影响较大等问题,以果园作业平台车架为研究对象,编制车架加速载荷谱,分析车架耐久性。采用有限元分析方法,对车架进行力学分析并选取关键载荷测点,建立果园作业平台多体动力学模型采集相应测点载荷谱,利用伪损伤保留编辑法获取不同伪损伤保留量的加速载荷谱,从压缩时间效率、伪损伤域、功率谱密度、穿级/雨流计数和统计值参数等方面对比,分析伪损伤保留量对加速载荷谱质量的影响。通过车架耐久性仿真对比不同编辑方案对耐久性分析精度和效率的影响。对比结果表明,伪损伤保留量不低于90%才能保证加速载荷谱的质量。仿真结果表明,车架最小寿命历程大约为65000 km,根据果园作业平台使用条件和用户使用情况调查,了解果园作业平台每年大约行驶8100 km,使用年限为8年,该车架满足要求。且伪损伤保留量为95%时为最佳编制方案,加速载荷谱时间压缩量为55%,车架耐久性仿真分析误差能控制在5%内且仿真效率提高391%,本文为提高农用机械部件耐久性载荷的编辑质量提供参考。 展开更多
关键词 果园作业平台 车架 加速载荷谱 伪损伤保留编制法 耐久性
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基于视觉增强的桥梁检测算法及技术
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作者 朱尧于 李佳欢 +3 位作者 朱力 刘玉静 何超 刘涛 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期902-910,共9页
为了识别桥梁结构微小振动,提出一种基于方向码匹配(OCM)法的靶标圆心检测算法.该算法首先采用OCM法实现像素级匹配,然后在最佳匹配区域采用靶标圆心检测算法进行精确跟踪.通过室内试验,将基于OCM的靶标圆心检测算法与基于相位的光流法... 为了识别桥梁结构微小振动,提出一种基于方向码匹配(OCM)法的靶标圆心检测算法.该算法首先采用OCM法实现像素级匹配,然后在最佳匹配区域采用靶标圆心检测算法进行精确跟踪.通过室内试验,将基于OCM的靶标圆心检测算法与基于相位的光流法和OCM亚像素实现算法进行对比,研究3种算法在不同振动幅度和实际工程应用的适用性,为实桥检测提供技术方案比选依据.结果表明:所提算法在各种振动幅度下均能精确地识别结构振动位移和频率,在实桥应用时应考虑靶标粘贴的可行性;基于相位的光流法在幅度指标小于2 mm或1.7像素的微小振动工况下能精确地识别结构的振动位移和频率;OCM亚像素实现算法的分辨精度取决于插值点的数量,对大幅度振动工况的识别具有与所提算法相似的效果. 展开更多
关键词 桥梁检测 适用性研究 视觉增强 方向码匹配 基于相位的光流法
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