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关于提高标定型房间量热计试验装置测量精度的探讨 被引量:2
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作者 陆亚俊 马最良 孙海峰 《家用电器科技》 1989年第4期26-28,共3页
提出了提高标定型房间量热计试验装置测试精度的技术措施。通过对空调器进行的多次制冷量测试及对同一台空调器在标定型和平衡型量热计试验台进行的对比试验,验证了这些技术措施对提高精度是有效的。
关键词 标定型 房间 量热计 试验装置
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一种大视场汇聚型双目立体视觉标定方法
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作者 崔帅华 余磊 +2 位作者 何茜 熊邦书 欧巧凤 《应用科学学报》 CAS CSCD 北大核心 2024年第2期269-279,共11页
双目摄像机汇聚型摆放易导致标记点出现散焦模糊和透视形变,使标记点定位出现偏差,在大视场环境下会引发不可忽视的标定误差,进而影响测量精度。为解决上述问题,提出了一种基于标记点定位偏差度加权的大视场汇聚型双目立体视觉标定方法... 双目摄像机汇聚型摆放易导致标记点出现散焦模糊和透视形变,使标记点定位出现偏差,在大视场环境下会引发不可忽视的标定误差,进而影响测量精度。为解决上述问题,提出了一种基于标记点定位偏差度加权的大视场汇聚型双目立体视觉标定方法。首先,利用靶标在摄像机坐标系下的位姿,计算标记点散焦模糊量和透视形变度;其次,根据标记点定位偏差度设置相应权重;最后,将标记点权重系数加入目标函数,引导标定参数优化。实验结果表明:在观测值为505 mm的情况下,该方法测距均方根误差和标准差可达0.809和0.290,不但有效提高了大视场汇聚型双目立体视觉标定精度,而且具有良好的稳定性。 展开更多
关键词 立体视觉 汇聚双目标定 大视场 定位偏差 加权优化
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摄像机标定中栅格型标定点的亚像素提取的研究 被引量:2
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作者 陈大志 王颖 张广军 《光学技术》 EI CAS CSCD 北大核心 2006年第1期53-55,58,共4页
介绍了一种新的摄像机标定用栅格型靶标标定点亚像素的提取方法。该方法先利用一个基于Hessian矩阵的形状算子判定栅格点的像素位置,然后对栅格点邻近区域内的图像灰度函数进行二阶泰勒展开,并通过计算该灰度曲面的局部极小值点来确定... 介绍了一种新的摄像机标定用栅格型靶标标定点亚像素的提取方法。该方法先利用一个基于Hessian矩阵的形状算子判定栅格点的像素位置,然后对栅格点邻近区域内的图像灰度函数进行二阶泰勒展开,并通过计算该灰度曲面的局部极小值点来确定栅格中心点的亚像素位置。相对于传统的直线拟合求交点的方法,该算法计算过程简单,且具有较高的提取精度。 展开更多
关键词 摄像机标定 栅格标定 亚像素提取
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GSYB型光栅数显式引伸计标定仪示值误差的测量不确定度评定及符合性评价 被引量:2
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作者 宋国斌 甘敏 《计量与测试技术》 2013年第7期50-51,共2页
针对我所研制的GSYB型引伸计标定仪,详细介绍了标定仪示值误差校准的测量不确定度及符合性评价。
关键词 GSYB引伸计标定 2等量块 三珠工作台 测微表座 不确定度
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一种标定手性中心和手性轴化合物构型的简便方法
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作者 佟宗先 《纺织基础科学学报》 1994年第3期267-270,共4页
对于楔形式表示的手性中心和手性轴化合物,给出在纸面上直接标定构型的方法.
关键词 手性中心 手性轴 标定
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司空见惯“规则”事 饱含深奥“科学”理——从城市交通规则说到“型位径效标定理论”
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作者 王宏强 《河南科技》 2000年第3期30-30,共1页
关键词 交通规则 位径效标定 标志标线制定 交通管理
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基于线激光和新型标定板的钢轨轮廓匹配方法 被引量:2
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作者 陈旭昂 韩言 +3 位作者 邓恒 周建华 李陈 余学才 《激光与红外》 CAS CSCD 北大核心 2023年第8期1279-1287,共9页
为解决钢轨轮廓检测中标定平面和激光平面不重合、钢轨轮廓难以动态匹配的问题,制作了一种阶梯型标定板,并提出基于Harris-SIFT和改进RANSAC算法的钢轨轮廓匹配方法。首先设计制作一种阶梯型钢轨轮廓标定板,能直接标定激光平面,避免了... 为解决钢轨轮廓检测中标定平面和激光平面不重合、钢轨轮廓难以动态匹配的问题,制作了一种阶梯型标定板,并提出基于Harris-SIFT和改进RANSAC算法的钢轨轮廓匹配方法。首先设计制作一种阶梯型钢轨轮廓标定板,能直接标定激光平面,避免了实际应用中标定平面与线激光平面不完全重合的问题。标定过程中采集最佳控制点,通过多项式变换和双线性插值进行图像校正,然后通过Harris-SIFT算法进行轮廓粗匹配,大大缩短了匹配时间,最后利用改进的随机抽样一致算法(RANSAC)进行轮廓误匹配滤除,实现了轮廓精匹配。实验结果表明,图像标定时,相对于棋盘格标定板,校正误差减小0.042 mm;轮廓匹配时,相对于传统轮廓匹配方法,改进后的轮廓匹配算法匹配运行时间快,正确率达100%。 展开更多
关键词 阶梯标定 图像校正 Harris-SIFT算法 轮廓匹配
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标定含有手性轴化合物构型的简单方法
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作者 马军营 《平顶山学院学报》 1997年第2期17-21,共5页
通过参阅大量的文献资料,并结合自己的教学体会,总结出了对不含手性碳原子的手性化合物构型的简单标定方法──透视式法.
关键词 手性 手性轴化合物 标定
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非量测数码相机标定方法研究 被引量:3
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作者 靳志光 卫建东 卢成静 《测绘技术装备》 2008年第2期46-48,共3页
图像全站仪是拓普康的一款创新性产品,但由于其内置相机的分辨率较低,所以一般配合非量测数码相机共同工作。为提高量测精度,拓普康用PI-Calib对相机进行标定。本文研究了它的标定方法,并进行了试验对比。
关键词 图像全站仪 非量测数码相机标定 试验分析
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On capped Higgs positivity cone
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作者 Dong-Yu Hong Zhuo-Hui Wang Shuang-Yong Zhou 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期44-54,43,I0003,共13页
The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to ... The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to the Wilson coefficients living in a convex cone,further including the nonpositivity part caps the cone from above.For Higgs scattering,a capped positivity cone was obtained using a simplified,linear unitarity condition without utilizing the full internal symmetries of Higgs scattering.Here,we further implement stronger nonlinear unitarity conditions from the UV,which generically gives rise to better bounds.We show that,for the Higgs case in particular,while the nonlinear unitarity conditions per se do not enhance the bounds,the fuller use of the internal symmetries do shrink the capped positivity cone significantly. 展开更多
关键词 positivity bounds standard model effective field theory(SMEFT) HIGGS
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Analysis of Protein Content in Panicum miliaceum L. Using Near Infrared Transmittance Spectroscopy 被引量:2
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作者 牛宇 蒙秋霞 +5 位作者 张丽珍 赵婷婷 乔治军 牛伟 刘根科 冯耐红 《Agricultural Science & Technology》 CAS 2012年第5期965-968,共4页
[Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy (NITS) was used to build the mathematical mo... [Objective] To explore a method for the rapid determination of protein con- tent in grains of Panicum miliaceum L. [Method] The near infrared transmittance spec- troscopy (NITS) was used to build the mathematical models for the quantitative analy- sis of protein content in the grains. Four combinations of treatment that first derivative and second derivative were respectively combined with partial least squares (PLS) and modified partial least squares (MPLS) were set to compare their effects on the original transmission spectrum. [Result] The predicting effects of the 4 combinations were similar. The optimal combination was first derivative with MPLS, in which the average determination coefficient of validation (RSQ) was 0.880 6, correlation coeffi- cient of cross validation (1-VR) was 0.857 0, standard error of calibration (SEC) was 0.342 4, standard error of cross validation (SECV) was 0.375 1, and the standard er- ror of prediction (SEP) was 0.454. [Conclusion] The constructed NITS model is a rapid way for the determination of protein content in grains of P. miliaceum. 展开更多
关键词 Near infrared transmittance spectroscopy Panicum miliaceum L. PROTEIN Calibration model
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0.5级引伸计示值误差的测量结果不确定度评定及符合性评价
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作者 宋国斌 《计量与测试技术》 2013年第8期84-85,87,共3页
针对引伸计示值误差的测量,详细介绍了使用我所研制的GSYB型引伸计标定仪对0.5级引伸计示值误差测量的测量结果不确定度以及其是否满足测量要求的符合性评价。
关键词 0 5级引伸计 GSYB引伸计标定 示值误差 不确定度
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Modeling of the Multi-Target Locating and Tracking in the Field Artillery System 被引量:1
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作者 杨国胜 窦丽华 +1 位作者 陈杰 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期14-18,共5页
A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ba... A method for the multi target locating and tracking with the multi sensor in a field artillery system is studied. A general modeling structure of the system is established. Based on concepts of cluster and closed ball, an algorithm is put forward for multi sensor multi target data fusion and an optimal solution for state estimation is presented. The simulation results prove the algorithm works well for the multi stationary target locating and the multi moving target tracking under the condition of the sparse target environment. Therefore, this method can be directly applied to the field artillery C 3I system. 展开更多
关键词 field artillery system data fusion closed ball cluster single sensor multi target multi sensor multi target
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Quik Read CRP分析仪与Nycocard READER Ⅱ型金标定量仪的临床应用评价 被引量:2
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作者 王立军 《热带医学杂志》 CAS 2009年第1期46-48,共3页
目的评价Quik Read CRP分析仪与Nycocard READER Ⅱ型金标定量仪进行C-反应蛋白(CRP)测定的可靠性。方法用Quik Read CRP分析仪及Nycocard READER Ⅱ型金标定量仪分别对不同浓度CRP标准血清,质控血清及30例病人血清进行测定,对比其精密... 目的评价Quik Read CRP分析仪与Nycocard READER Ⅱ型金标定量仪进行C-反应蛋白(CRP)测定的可靠性。方法用Quik Read CRP分析仪及Nycocard READER Ⅱ型金标定量仪分别对不同浓度CRP标准血清,质控血清及30例病人血清进行测定,对比其精密度、准确性和线性,并行干扰试验,经统计学方法进行数据处理,再作相关性比较。结果实验数据表明,两种仪器相关性良好(r=0.955),且两种仪器受溶血、甘油三酯(TG)以及胆红素因素的干扰影响极小。结论这两种仪器精密度和线性较好,准确度较高,抗干扰能力强,具有简便、快速、仪器维护简单等优点,可用于急诊及常规CRP检查,并可适用于多种形式的血液标本(血清、血浆、末梢血及静脉全血)。 展开更多
关键词 Quik READ CRP分析仪 Nycocard READER 标定量仪 C-反应蛋白
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Core outcome set for stable angina pectoris in traditional Chinese medicine(COS-SAP-TCM) 被引量:12
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作者 Mingyan Zhang Junhua Zhang +3 位作者 Hui Zi Chua Rui Feng Meijuan Lu Ying Tian 《Acupuncture and Herbal Medicine》 2021年第1期39-48,共10页
Objective:This study aimed to develop a core outcome set(COS)for use in future studies of stable angina pectoris(SAP)in traditional Chinese medicine(TCM).Methods:Systematic literature reviews and qualitative interview... Objective:This study aimed to develop a core outcome set(COS)for use in future studies of stable angina pectoris(SAP)in traditional Chinese medicine(TCM).Methods:Systematic literature reviews and qualitative interviews with cardiologists and patients with SAP treated using TCM were conducted to generate a set of outcomes.Outcomes were prioritized by stakeholders via two rounds of an online Delphi survey and face-to-face consensus meetings.Following the final consensus meeting,a final COS was generated.Results:An initial set of 324 outcomes was identified.A preliminary list of 65 outcomes was employed in the Delphi study.In total,223 participants from seven stakeholder groups were invited to score outcomes in the first Delphi round:87 completed round 1 and 47 completed round 2.Thirty-one participants attended the consensus meeting and agreed on a final core set of outcomes comprising six items across four domains:frequency of angina attack,duration of angina attack,Seattle angina questionnaire,total exercise duration in the exercise treadmill test,cardiovascular events,and QT interval on electrocardiography.Conclusions:The COS developed in this study provides the minimum requirements for measurement and reporting in future TCM clinical trials for the treatment of SAP.The employment of this COS may reduce heterogeneity across trials and facilitate evidencebased decision-making for stakeholders. 展开更多
关键词 Core outcome set Outcome measure Stable angina pectoris Traditional Chinese medicine
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A multi-objective model for cordon-based congestion pricing schemes with nonlinear distance tolls 被引量:1
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作者 孙鑫 刘志远 +3 位作者 THOMPSON Russell G 别一鸣 翁金贤 陈淑燕 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1273-1282,共10页
Congestion pricing is an important component of urban intelligent transport system.The efficiency,equity and the environmental impacts associated with road pricing schemes are key issues that should be considered befo... Congestion pricing is an important component of urban intelligent transport system.The efficiency,equity and the environmental impacts associated with road pricing schemes are key issues that should be considered before such schemes are implemented.This paper focuses on the cordon-based pricing with distance tolls,where the tolls are determined by a nonlinear function of a vehicles' travel distance within a cordon,termed as toll charge function.The optimal tolls can give rise to:1) higher total social benefits,2) better levels of equity,and 3) reduced environmental impacts(e.g.,less emission).Firstly,a deterministic equilibrium(DUE) model with elastic demand is presented to evaluate any given toll charge function.The distance tolls are non-additive,thus a modified path-based gradient projection algorithm is developed to solve the DUE model.Then,to quantitatively measure the equity level of each toll charge function,the Gini coefficient is adopted to measure the equity level of the flows in the entire transport network based on equilibrium flows.The total emission level is used to reflect the impacts of distance tolls on the environment.With these two indexes/measurements for the efficiency,equity and environmental issues as well as the DUE model,a multi-objective bi-level programming model is then developed to determine optimal distance tolls.The multi-objective model is converted to a single level model using the goal programming.A genetic algorithm(GA) is adopted to determine solutions.Finally,a numerical example is presented to verify the methodology. 展开更多
关键词 distance-based toll charging schemes EQUITY path-based gradient projection algorithm non-additive goal programming
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Non-parametric camera calibration method using single-axis rotational target
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作者 FU Luhua REN Zeguang +2 位作者 WANG Peng SUN Changku ZHANG Baoshang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期1-11,共11页
The ability to build an imaging process is crucial to vision measurement.The non-parametric imaging model describes an imaging process as a pixel cluster,in which each pixel is related to a spatial ray originated from... The ability to build an imaging process is crucial to vision measurement.The non-parametric imaging model describes an imaging process as a pixel cluster,in which each pixel is related to a spatial ray originated from an object point.However,a non-parametric model requires a sophisticated calculation process or high-cost devices to obtain a massive quantity of parameters.These disadvantages limit the application of camera models.Therefore,we propose a novel camera model calibration method based on a single-axis rotational target.The rotational vision target offers 3D control points with no need for detailed information of poses of the rotational target.Radial basis function(RBF)network is introduced to map 3D coordinates to 2D image coordinates.We subsequently derive the optimization formulization of imaging model parameters and compute the parameter from the given control points.The model is extended to adapt the stereo camera that is widely used in vision measurement.Experiments have been done to evaluate the performance of the proposed camera calibration method.The results show that the proposed method has superiority in accuracy and effectiveness in comparison with the traditional methods. 展开更多
关键词 camera calibration rotational target non-parametric model
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Scaling Behavior of an Aggregation-Migration Model
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作者 KEJian-Hong LINZhen-Quan ZHUANGYou-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期781-786,共6页
We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation occurs between any two clusters of the same species and a reversible migration occurs simultaneously betw... We study the kinetic behavior of a two-species aggregation-migration model in which an irreversible aggregation occurs between any two clusters of the same species and a reversible migration occurs simultaneously between two different species. For a simple model with constant aggregation rates and with the migration rates and , we find that the evolution behavior of the system depends crucially on the values of the indexes υ<SUB>1</SUB> and υ<SUB>2</SUB>. The aggregate size distribution of either species obeys a conventional scaling law for most cases. Moreover, we also generalize the two-species system to the multi-species case and analyze its kinetic behavior under the symmetrical conditions. 展开更多
关键词 kinetic behavior aggregation-migration process scaling law
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Multi-objective intelligent coordinating optimization blending system based on qualitative and quantitative synthetic model 被引量:3
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作者 王雅琳 马杰 +2 位作者 桂卫华 阳春华 张传福 《Journal of Central South University of Technology》 EI 2006年第5期552-557,共6页
A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism a... A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism and neural network quantitative models for predicting compositions and rule models for expert reasoning were constructed based on statistical data and empirical knowledge. An expert reasoning method based on these models were proposed to solve blending optimization problem, including multi-objective optimization for the first blending process and area optimization for the second blending process, and to determine optimal mixture ratio which will meet the requirement of intelligent coordination. The results show that the qualified rates of agglomerate Pb, Zn and S compositions are increased by 7.1%, 6.5% and 6.9%, respectively, and the fluctuation of sintering permeability is reduced by 7.0%, which effectively stabilizes the agglomerate compositions and the permeability. 展开更多
关键词 Pb-Zn sintering blending process qualitative and quantitative synthetic model multi-objectiveoptimization area optimization intelligent coordination
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Multi-objective planning model for simultaneous reconfiguration of power distribution network and allocation of renewable energy resources and capacitors with considering uncertainties 被引量:9
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作者 Sajad Najafi Ravadanegh Mohammad Reza Jannati Oskuee Masoumeh Karimi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1837-1849,共13页
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a... This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration. 展开更多
关键词 optimal reconfiguration renewable energy resources sitting and sizing capacitor allocation electric distribution system uncertainty modeling scenario based-stochastic programming multi-objective genetic algorithm
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