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Relative peripheral refractive errors in Chinese children with myopic anisometropia
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作者 Yu-Ting Tong Yu-Qin Du +4 位作者 Shan-Shan Ge Li Chen Xiao-Qi Ma Yu-Juan Guo Yue-Hua Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2074-2081,共8页
AIM:To compare relative peripheral refractive errors(RPREs)in Chinese children with and without myopic anisometropia(MAI)and to explore the relationship between RPRE and myopia.METHODS:This observational cross-section... AIM:To compare relative peripheral refractive errors(RPREs)in Chinese children with and without myopic anisometropia(MAI)and to explore the relationship between RPRE and myopia.METHODS:This observational cross-sectional study included 160 children divided into two groups according to the interocular spherical equivalent refraction(SER)difference≥1.0 D in the MAI group(n=80)and<1.0 D in the non-MAI group(n=80).The MAI group was further divided into two subgroups:ΔSER<2.0 D group and ΔSER≥2.0 D group.Basic ocular biometric parameters of axial length(AL),average keratometry(Ave K),cylinder(CYL),surface regularity index(SRI),and surface asymmetry index(SAI)were recorded.In addition,multispectral refraction topography was performed to measure RPRE,and the parameters were recorded as total refraction difference value(TRDV),refraction difference value(RDV)0-10,RDV10-20,RDV20-30,RDV30-40,RDV40-53,RDV-superior(RDV-S),RDV-inferior(RDV-I),RDV-temporal(RDV-T)and RDV-nasal(RDV-N).RESULTS:In the non-MAI group,the interocular differences of all parameters of RPRE were not significant.In the MAI group,the interocular differences of TRDV,RDV10-53,RDV-S,RDV-I,RDV-T,and RDV-N were significant.In subgroup analysis,the interocular differences of TRDV,RDV30-53,RDV-I,and RDV-T were significant in ΔSER<2.0 D group and ΔSER≥2.0 D group,but the interocular differences of RDV10-30,RDV-S and RDV-N were only significant in the ΔSER≥2.0 D group.In correlation analysis,ΔTRDV,ΔRDV 10-53,ΔRDV-S,and ΔRDV-N were negatively correlated with ΔSER but positively correlated with ΔAL.CONCLUSION:The more myopic eyes have larger hyperopic RPRE in Chinese children with MAI in certain retinal range,and partialΔRPRE is closely associated with ΔSER and ΔAL. 展开更多
关键词 MYOPIA ANISOMETROPIA relative peripheral refractive error ocular biometric parameters
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Motor Imagery and Error Related Potential Induced Position Control of a Robotic Arm 被引量:5
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作者 Saugat Bhattacharyya Amit Konar D.N.Tibarewala 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第4期639-650,共12页
The paper introduces an electroencephalography(EEG) driven online position control scheme for a robot arm by utilizing motor imagery to activate and error related potential(ErrP) to stop the movement of the individual... The paper introduces an electroencephalography(EEG) driven online position control scheme for a robot arm by utilizing motor imagery to activate and error related potential(ErrP) to stop the movement of the individual links, following a fixed(pre-defined) order of link selection. The right(left)hand motor imagery is used to turn a link clockwise(counterclockwise) and foot imagery is used to move a link forward. The occurrence of ErrP here indicates that the link under motion crosses the visually fixed target position, which usually is a plane/line/point depending on the desired transition of the link across 3D planes/around 2D lines/along 2D lines respectively. The imagined task about individual link's movement is decoded by a classifier into three possible class labels: clockwise, counterclockwise and no movement in case of rotational movements and forward, backward and no movement in case of translational movements. One additional classifier is required to detect the occurrence of the ErrP signal, elicited due to visually inspired positional link error with reference to a geometrically selected target position. Wavelet coefficients and adaptive autoregressive parameters are extracted as features for motor imagery and ErrP signals respectively. Support vector machine classifiers are used to decode motor imagination and ErrP with high classification accuracy above 80%. The average time taken by the proposed scheme to decode and execute control intentions for the complete movement of three links of a robot is approximately33 seconds. The steady-state error and peak overshoot of the proposed controller are experimentally obtained as 1.1% and4.6% respectively. 展开更多
关键词 Brain-computer interfacing(BCI) error related potential(Errp) motor imagery decoding position control of a robot arm
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A new calculation approach of wellbore separation factor based on the relative position of adjacent wells
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作者 HONG Difeng TANG Xueping +3 位作者 GAO Wenkai MAO Weimin WANG Peng LIU Ke 《Petroleum Exploration and Development》 2020年第1期196-203,共8页
As the current calculation methods for wellbore separation factor have some deficiencies, we propose and analyze a new calculation approach for wellbore separation factor based on the relative position of adjacent wel... As the current calculation methods for wellbore separation factor have some deficiencies, we propose and analyze a new calculation approach for wellbore separation factor based on the relative position of adjacent wellbores, named as relative position method for short. Based on the trajectory error ellipsoid model of single wellbore, the error ellipsoids model of adjacent wellbore was derived considering the correlation of trajectory errors between adjacent wells. Furthermore, the calculation formula of the separation factor based on relative position of adjacent wellbore was derived and solved with the conjugate gradient algorithm. Case study shows that the new approach is more precise and higher in applicability than the ellipsoid scaling method and the minimum distance method, it can evaluate the state of well collision more reasonably. By doing batch calculation with the new method and following the criterion of well collision avoidance, the permissible ranges of key parameters in the well design can be worked out quickly. This method has good application in the design of cluster wells and directional wells. 展开更多
关键词 wellhole separation factor wellhole COLLISION AVOIDANCE relative wellbores error CONJUGATE gradient algorithm cluster WELLS
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民法典中意思表示解释规则视野下的重大误解——以意思表示错误为基础
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作者 隋彭生 《山东师范大学学报(社会科学版)》 CSSCI 北大核心 2024年第5期63-74,共12页
对重大误解的认定是一项意思表示解释的工作。民法典第142条区分有相对人的意思表示和无相对人的意思表示,对前者采表示主义的解释标准,对后者采意思主义的解释标准。解释标准,是对错误应否救济、应否认定为重大误解的标准。通过提出动... 对重大误解的认定是一项意思表示解释的工作。民法典第142条区分有相对人的意思表示和无相对人的意思表示,对前者采表示主义的解释标准,对后者采意思主义的解释标准。解释标准,是对错误应否救济、应否认定为重大误解的标准。通过提出动机他项事实错误和动机同项事实错误两个创新概念,解决立法例尚未解决的动机进入效果意思的问题。不能对抗善意相对人的错误、非重大错误以及可以通过意思表示解释修正的错误,不构成重大误解。 展开更多
关键词 重大误解 原因错误 动机他项事实错误 动机同项事实错误 意思表示解释标准
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轻度认知功能障碍患者不同频率重复经颅磁刺激康复治疗效果研究
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作者 江柏梅 刘钰 +6 位作者 陈玄玄 杜爱卿 朱菁菁 汪卫立 钟海潮 傅永强 陈兴时 《临床精神医学杂志》 CAS 2024年第3期234-237,共4页
目的:观察不同频率重复经颅磁刺激(rTMS)对老年轻度认知功能障碍(MCI)患者精神行为症状的影响以及康复治疗效果评价。方法:采用随机数字表法,将90例伴有精神行为症状的MCI患者随机分为3组,分别给予5 Hz、10 Hz和15 Hz的rTMS治疗6周(30... 目的:观察不同频率重复经颅磁刺激(rTMS)对老年轻度认知功能障碍(MCI)患者精神行为症状的影响以及康复治疗效果评价。方法:采用随机数字表法,将90例伴有精神行为症状的MCI患者随机分为3组,分别给予5 Hz、10 Hz和15 Hz的rTMS治疗6周(30次),分别于治疗前后测定并比较患者简易精神状态检查(MMSE)分值、P300、错误相关负电位(ERN)的潜伏期和波幅。结果:与治疗前相比:(1)10 Hz组患者rTMS治疗后MMSE量表分值明显增高(P<0.05),而5 Hz和15 Hz组MMSE量表分值无明显改善;(2)10 Hz组患者rTMS治疗后P300和ERN波幅提高(P均<0.05);潜伏期两组差异无统计学意义(P>0.05),其余两组治疗前后P300和ERN潜伏期和波幅均未见明显变化。(3)10 Hz患者组MMSE分值的改善状况与患者年龄及病程有关。结论:高频10 Hz的rTMS对MCI患者精神行为症状具有明显缓解作用,同时能改善患者认知功能,该高频疗法值得临床进一步推广。P300和ERN可用于随访评估。 展开更多
关键词 轻度认知功能障碍 重复经颅磁刺激 P300 错误相关负电位 康复评估
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Software Cost Estimation Using Social Group Optimization
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作者 Sagiraju Srinadhraju Samaresh Mishra Suresh Chandra Satapathy 《Computer Systems Science & Engineering》 2024年第6期1641-1668,共28页
This paper introduces the integration of the Social Group Optimization(SGO)algorithm to enhance the accuracy of software cost estimation using the Constructive Cost Model(COCOMO).COCOMO’s fixed coefficients often lim... This paper introduces the integration of the Social Group Optimization(SGO)algorithm to enhance the accuracy of software cost estimation using the Constructive Cost Model(COCOMO).COCOMO’s fixed coefficients often limit its adaptability,as they don’t account for variations across organizations.By fine-tuning these parameters with SGO,we aim to improve estimation accuracy.We train and validate our SGO-enhanced model using historical project data,evaluating its performance with metrics like the mean magnitude of relative error(MMRE)and Manhattan distance(MD).Experimental results show that SGO optimization significantly improves the predictive accuracy of software cost models,offering valuable insights for project managers and practitioners in the field.However,the approach’s effectiveness may vary depending on the quality and quantity of available historical data,and its scalability across diverse project types and sizes remains a key consideration for future research. 展开更多
关键词 Manhattan distance mean magnitude of relative error nature-inspired algorithms project management SGO
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改进ANFIS对静压箱热误差建模研究
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作者 钱雨鲲 李岩舟 +3 位作者 杨正昊 秦承斌 王佳宁 吴媚 《机械科学与技术》 CSCD 北大核心 2024年第10期1778-1785,共8页
为了减小静压箱排气孔温度不均匀对薄膜拉伸加工时的影响,通过建立热误差模型,来分析静压箱在不同输入参数下排气孔的温场情况。采用SOM-GRA相结合的综合算法得出最优测温点,以保证输入模型的数据具有代表性,将测温点数量由20降至3。利... 为了减小静压箱排气孔温度不均匀对薄膜拉伸加工时的影响,通过建立热误差模型,来分析静压箱在不同输入参数下排气孔的温场情况。采用SOM-GRA相结合的综合算法得出最优测温点,以保证输入模型的数据具有代表性,将测温点数量由20降至3。利用ANFIS模型建立静压箱的热误差模型,并通过RF算法优化ANFIS中隶属度函数数量参数,将实验验证过的数值模拟数据作为输入的训练数据。预测结果表明较原ANFIS模型、BP模型和RBF模型MAE值分别下降了22.43%、59.97%和49.87%,该优化预测模型具有更高的精度。 展开更多
关键词 热误差模型 自组织映射网络 灰色关联分析 随机森林 自适应神经模糊推理系统
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动机在错误加工中的不一致效应:争议与整合
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作者 李亚琴 赵若兰 杨庆 《心理科学进展》 CSSCI CSCD 北大核心 2024年第1期85-99,共15页
错误加工(error processing)是个体探测错误发生并进行针对性调整的高级认知过程。大量研究表明,动机(如奖励、惩罚等)能够影响错误加工过程,但结果并不一致。本文在梳理和比较以往研究的基础上提出,年龄、性别、实验设计、人格和文化... 错误加工(error processing)是个体探测错误发生并进行针对性调整的高级认知过程。大量研究表明,动机(如奖励、惩罚等)能够影响错误加工过程,但结果并不一致。本文在梳理和比较以往研究的基础上提出,年龄、性别、实验设计、人格和文化等因素可能影响动机与错误加工的关系。通过进一步整合,提出任务相关性(task relevance)可能是潜在的共同作用机制,即在与个体目标高相关的任务中,动机越强则错误加工程度增强(如更大的ERN、Pe波幅);而在低相关任务中,动机对错误加工的影响较弱。在这一理论框架下,上述因素可能通过影响任务相关性进而调节动机与错误加工的关系,新观点的提出有助于解释动机与错误加工关系的矛盾结果。未来一是需要系统验证上述因素及任务相关性的作用,二是关注不同类型错误和错误本身的动机作用,三是进一步探究动机与认知因素如何共同影响错误加工,这些将有助于完善和推进动机取向的错误加工理论。 展开更多
关键词 错误加工 动机 错误相关负波 错误正波 任务相关性
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运动员动作预期中错误监控的认知调节机制:来自行为与ERP的证据
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作者 李亚伟 冯甜 《首都体育学院学报》 CSSCI 北大核心 2024年第4期426-434,463,共10页
目的:从错误监控视角探究运动员的动作预期错误监控与脑活动的认知调节机制。方法:40人[优秀组(一级篮球运动员)和新手组(非篮球专项的体育专业大学生)]观看不同判断时间点(出手阶段、上升阶段、高点阶段和下落阶段)和投篮结果(命中与... 目的:从错误监控视角探究运动员的动作预期错误监控与脑活动的认知调节机制。方法:40人[优秀组(一级篮球运动员)和新手组(非篮球专项的体育专业大学生)]观看不同判断时间点(出手阶段、上升阶段、高点阶段和下落阶段)和投篮结果(命中与未命中)的投篮视频,进行投篮结果预期及错误意识水平报告;同时记录并分析被试判断正确率、判断确信程度、P3、N400、ERN及Pe成分的潜伏期和峰波幅。结果:优秀组在投篮动作的早期阶段对命中情况的判断正确率更高,对未命中情况的判断正确率更低,判断确信程度与判断正确率呈正相关关系;优秀组的ERN峰波幅显著大于新手组,P3峰波幅有大于新手组的趋势,在未命中情况下的N400峰波幅更大,在命中情况下的Pe峰波幅更小。结论:1)运动经验可以提高运动员的错误监控能力,且优秀运动员的动作预期错误监控的时程表现在动作执行的早期阶段;2)优秀运动员的错误监控能力在行为特征和认知神经变化2个方面均显现出优势,且错误监控能力的强弱会影响动作预期的绩效;3)优秀运动员的错误监控行为可以调节运动经验对动作预期绩效的影响过程。 展开更多
关键词 动作预期 错误监控 调节机制 运动员 事件相关电位(ERP)
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基于疾病诊断相关分组付费原理分析乳腺癌手术操作编码的错误案例
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作者 余艳 蔡庆婷 +3 位作者 黄云 刘体娟 王娜娜 徐洪斌 《实用医技杂志》 2024年第3期215-218,共4页
目的为分析基于病病诊断相关分组(DRGs)分组付费原理分析乳腺癌手术操作编码的错误案例以减少手术操作编码错误的情况。方法本研究在2019年7月至2023年7月期间于在我院接受乳腺癌手术治疗的患者为研究对象,基于DRGs分组原理收集了乳腺... 目的为分析基于病病诊断相关分组(DRGs)分组付费原理分析乳腺癌手术操作编码的错误案例以减少手术操作编码错误的情况。方法本研究在2019年7月至2023年7月期间于在我院接受乳腺癌手术治疗的患者为研究对象,基于DRGs分组原理收集了乳腺癌手术治疗的患者380例,并对这些患者的病案数据进行核查,收集核查结果包括不同手术方式以及不同分期患者中错误编码的发生率情况、错误编码的类别分布以及错误编码的责任人情况。结果通过对380例患者的病案数据核查,发现其中有错误编码案例44例,不同手术方式以及不同分期患者中错误编码的发生率情况差异无统计学意义(χ^(2)=2.504,P>0.05),编码不完整错误有5例,编码不准确有17例、编码不规范有18例、编码不一致有4例,分别占错误编码的比例11.4%、38.6%、40.9%以及9.1%;临床医师发生错误编码情况有39例占总错误的比例为88.6%、编码员发生错误情况有5例占总错误的比例为11.4%。结论我院编码错误类型主要是编码不准确以及编码不规范的问题,并且临床医师发生错误编码情况较多。 展开更多
关键词 乳腺肿瘤 按病种分组付费 临床编码 错误案例
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基于灰色关联分析的船舶碰撞人为失误影响因素研究
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作者 葛岩 刘盛 杜冬冬 《广州航海学院学报》 2024年第3期13-18,共6页
为避免船舶碰撞事故发生,构建由软件、硬件、环境和人组成的模型(Software Hardware Environment Liveware,SHEL),形成避让操纵流程图,设置调查问卷识别出具体的13项人为失误影响因素。基于灰色关联分析法(Grey Relation Analysis,GRA)... 为避免船舶碰撞事故发生,构建由软件、硬件、环境和人组成的模型(Software Hardware Environment Liveware,SHEL),形成避让操纵流程图,设置调查问卷识别出具体的13项人为失误影响因素。基于灰色关联分析法(Grey Relation Analysis,GRA)对各项人为因素与船舶碰撞事故之间的关联度进行分析。结果显示,各项因素与船舶碰撞事故之间的关联度为0.720~0.976,均为重要因素,其中,未保持正规瞭望与发生碰撞之间的关联程度最高。对人为因素与碰撞事故之间的关联度进行排序,得出各因素与碰撞事故发生之间的紧密程度,从而为船舶避碰操纵提供一定的借鉴和参考。 展开更多
关键词 船舶碰撞 SHEL模型 人为失误因素 灰色关联分析 关联度排序
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3-D fracture network dynamic simulation based on error analysis in rock mass of dam foundation 被引量:4
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作者 ZHONG Deng-hua WU Han +2 位作者 WU Bin-ping ZHANG Yi-chi YUE Pan 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期919-935,共17页
Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network mode... Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network model and measured data,a 3-D fracture network dynamic modeling method based on error analysis was proposed.Firstly,errors of four fracture volume density estimation methods(proposed by ODA,KULATILAKE,MAULDON,and SONG)and that of four fracture size estimation methods(proposed by EINSTEIN,SONG and TONON)were respectively compared,and the optimal methods were determined.Additionally,error index representing the deviation between fracture network model and measured data was established with integrated use of fractal dimension and relative absolute error(RAE).On this basis,the downhill simplex method was used to build the dynamic modeling method,which takes the minimum of error index as objective function and dynamically adjusts the fracture density and size parameters to correct the error index.Finally,the 3-D fracture network model could be obtained which meets the requirements.The proposed method was applied for 3-D fractures simulation in Miao Wei hydropower project in China for feasibility verification and the error index reduced from 2.618 to 0.337. 展开更多
关键词 rock mass of dam foundation 3-D fracture network dynamic simulation fractal dimension error analysis relative absolute error(RAE) downhill simplex method
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Research of contour error compensation control for X-C non-circular grinding in polar coordinates 被引量:6
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作者 LI Qiguang HAN Qiushi +1 位作者 PENG Baoying WANG Hongjun 《Instrumentation》 2014年第1期29-37,共9页
In the X-C linkage grinding of non-circular parts,the computation and control method of contour error in polar coordinates platform is different with that in the XY coordinates platform.To solve this problem,the analy... In the X-C linkage grinding of non-circular parts,the computation and control method of contour error in polar coordinates platform is different with that in the XY coordinates platform.To solve this problem,the analysis of the definition and computation methods for contour error and track error in polar coordinates platform will be made.Through the relative lead-lag relation of the linkage axes in the grinding process,the range of the estimation contour error is narrowed and a contour error calculation model is constructed.Then the contour compensation controllers along contour error direction and trajectory tracking error direction are designed respectively,and the error compensation decoupling matrix of the X-C linkage axes is given as well.In the end of this paper,we take the machining of the cylinder contour in Wankel rotary piston engine as an example.A simulation experiment of contour error compensation control based on relative lead-lag quantity is made.The result shows that the designed contour compensation controller can increase the contour machining accuracy effectively. 展开更多
关键词 polar coordinates X-C grinding non-circular contour relative lead-lag contour error
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An Approach to Reasoning Topological Relations Between Areal Objects Under Randomness
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作者 DENGMin ZHANGXuesong LIUWenbao 《Geo-Spatial Information Science》 2004年第4期255-261,278,共8页
This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On ... This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On the basis of this, the effects of positional uncertainty on topological relations between areal objects are investigated in detail. Some possibility functions for the determination of relations are constructed based on the assumption that randomness of point location complies with a normal distribution, and the concept of uncertain sets of topological relations under randomness is introduced. 展开更多
关键词 topological relations RANDOMNESS positional error
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Detecting and Repairing Data-Flow Errors in WFD-net Systems
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作者 Fang Zhao Dongming Xiang +2 位作者 Guanjun Liu Changjun Jiang Honghao Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1337-1363,共27页
Workflow system has become a standard solution for managing a complex business process.How to guarantee its correctness is a key requirement.Many methods only focus on the control-flow verification,while they neglect ... Workflow system has become a standard solution for managing a complex business process.How to guarantee its correctness is a key requirement.Many methods only focus on the control-flow verification,while they neglect the modeling and checking of data-flows.Although some studies are presented to repair the data-flow errors,they do not consider the effect of delete operations or weak circulation relations on the repairing results.What’s more,repairing some data-flow errors may bring in new errors.In order to solve these problems,we use workflow net with data(WFD-net)systems to model and analyze a workflow system.Based on weak behavioral relations and order relations in a WFD-net system,we formalize four kinds of data-flow errors.After then,we reveal the relations between these errors and organize them into a hierarchy.Furthermore,we propose some new methods to repair data-flow errors in a WFD-net system based on system requirements and repair strategies.Finally,a case study of campus-card recharging shows the applicability of our methods,and a group of experiments show their advantages and effectiveness. 展开更多
关键词 Data-flow errors WFD-net weak behavioral relations system requirements
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The Satellite’s On-Orbit Attitude System Error Compensation Technique Based on Stereo Models
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作者 Yu Zhou Xin Hu +1 位作者 Peng Du Yi Wang 《Journal of Computer and Communications》 2020年第6期42-53,共12页
<div style="text-align:justify;"> According to the problem that the low measurement accuracy of TH-1 satellite star sensor, the low frequency and “slow drift” error which cannot be ignored in the att... <div style="text-align:justify;"> According to the problem that the low measurement accuracy of TH-1 satellite star sensor, the low frequency and “slow drift” error which cannot be ignored in the attitude determination system, resulting in obvious random error in the horizontal position and elevation direction, and the change of the error with time and latitude, cannot be calibrated by the ground field of the real problem. In this paper, a low frequency detection model is established by using the principle of relative orientation, and the low frequency error is obtained by parallax elimination. Finally, the satellite attitude is compensated and the more accurate exterior orientation elements are obtained, thus improving the positioning accuracy and stability. The experimental results show that: the proposed methods are feasible, and by using the model to dynamically calibrate the exterior orientation angle elements on orbit, the plane and elevation errors of the ground points can be basically eliminated. The global uncontrollable positioning accuracy and stability of the photogrammetry satellite are improved. </div> 展开更多
关键词 Attitude Measuring System Low Frequency error Dynamic Calibration relative Orientation
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Relation between the Actual and Estimated Maximum Ground Level Concentration of Air Pollutant and Its Downwind Locations
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作者 Khaled S. M. Essa Soad M. Etman Maha S. El-Otaify 《Open Journal of Air Pollution》 2020年第2期27-35,共9页
In this work we used the Gaussian plume model to calculate the actual maximum ground level concentration (MGLC) of air pollutant and its downwind location by using different systems of dispersion parameters and for di... In this work we used the Gaussian plume model to calculate the actual maximum ground level concentration (MGLC) of air pollutant and its downwind location by using different systems of dispersion parameters and for different stack heights. An approximate formula for the prediction of downwind position that produces the MGLC of a pollutant based on the Gaussian formula was derived for different diffusion parameters. The derived formula was used to calculate the approximate MGLC. The actual and estimated values are presented in tables. The comparison between the actual and estimated values was investigated through the calculation of the relative errors. The values of the relative errors between the actual and estimated MGLC lie in the range from: 0 to 70.2 and 0 to 1.6 for Pasquill Gifford system and Klug system respectively. The errors between the actual and estimated location of the MGLC lies in the range from: 0.2 to 227 and 0.7 to 9.4 for Pasquill Gifford system and Klug system respectively. 展开更多
关键词 Gaussian Plume Model Actual and Estimated Values relative errors
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基于CNN-GRU组合神经网络的数控机床进给系统热误差研究 被引量:7
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作者 孙兴伟 杨铜铜 +2 位作者 杨赫然 董祉序 刘寅 《仪器仪表学报》 EI CAS CSCD 北大核心 2023年第10期219-226,共8页
热变形引起的误差是影响数控机床精度的主要因素之一。为了减小热误差对数控机床精度的影响,提出一种基于CNN-GRU组合神经网络的热误差预测方法。通过热误差实验,采集螺旋曲面专用数控机床直线进给系统的温升数据和热误差数据;利用模糊... 热变形引起的误差是影响数控机床精度的主要因素之一。为了减小热误差对数控机床精度的影响,提出一种基于CNN-GRU组合神经网络的热误差预测方法。通过热误差实验,采集螺旋曲面专用数控机床直线进给系统的温升数据和热误差数据;利用模糊C均值聚类和灰色关联度分析筛选进给系统温度敏感点;以温度敏感点的温升数据和进给系统热误差为数据样本,建立CNN-GRU热误差预测模型。为验证模型的准确性和实用性,与基于CNN-LSTM和基于LSTM的传统热误差预测模型进行预测对比分析,结果表明CNN-GRU模型预测结果的平均绝对误差、均方根误差和决定系数均优于CNN-LSTM模型和LSTM模型,具有较高的预测精度和鲁棒性。提供的热误差模型可为后续误差补偿奠定基础,为数控机床的热误差预测提供思路。 展开更多
关键词 模糊C均值聚类 灰色关联度分析 进给系统 温度敏感点 误差预测
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Clinical decision support for drug related events: Moving towards better prevention 被引量:2
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作者 Sandra L Kane-Gill Archita Achanta +1 位作者 John A Kellum Steven M Handler 《World Journal of Critical Care Medicine》 2016年第4期204-211,共8页
Clinical decision support(CDS) systems with automated alerts integrated into electronic medical records demonstrate efficacy for detecting medication errors(ME) and adverse drug events(ADEs). Critically ill patients a... Clinical decision support(CDS) systems with automated alerts integrated into electronic medical records demonstrate efficacy for detecting medication errors(ME) and adverse drug events(ADEs). Critically ill patients are at increased risk for ME, ADEs and serious negative outcomes related to these events. Capitalizing on CDS to detect ME and prevent adverse drug related events has the potential to improve patient outcomes. The key to an effective medication safety surveillance system incorporating CDS is advancing the signals for alerts by using trajectory analyses to predict clinical events, instead of waiting for these events to occur. Additionally, incorporating cutting-edge biomarkers into alert knowledge in an effort to identify the need to adjust medication therapy portending harm will advance the current state of CDS. CDS can be taken a step further to identify drug related physiological events, which are less commonly included in surveillance systems. Predictive models for adverse events that combine patient factors with laboratory values and biomarkers are being established and these models can be the foundation for individualized CDS alerts to prevent impending ADEs. 展开更多
关键词 Drug-related side effects and ADVERSE reactions DECISION support SYSTEMS CLINICAL Medication errors Patient safety CLINICAL pharmacy information SYSTEMS Intensive CARE units Critical CARE ADVERSE DRUG event CLINICAL DECISION support SYSTEMS
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Dynamic Relation Mechanism between Cotton Future Price and Stock Price of Related Listed Companies
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作者 LIU Peng College of Food Science and Technology,Nanjing Agricultural University,Nanjing 210095,China 《Asian Agricultural Research》 2011年第5期140-143,150,共5页
The Dynamic relation mechanism between ZCE cotton futures price and related listed company stock price has been studied based on the metastock historical data in January 1st,2007 to September 1st,2010,Johansen co-inte... The Dynamic relation mechanism between ZCE cotton futures price and related listed company stock price has been studied based on the metastock historical data in January 1st,2007 to September 1st,2010,Johansen co-integration analysis,Vector error correction model,Granger causality test and variance decomposition method.The results indicated that:long-term equilibrium relationship existed between ZCE cotton futures price and Xinsai share stock price while which changed in the same tendency and speed in the long-term.Cotton futures price is the main reason for the changing of Xinsai share stock price.The lead-lag relationship in changing course had been confirmed that existed between ZCE cotton futures price and the Xinsai share stock price.Meanwhile,the forward pass mechanism of price changing information had been found only from the ZCE cotton futures market to the stock market while showing asymmetry.Conclusions of the study can be used for cotton and related corporate to hedge business risks by the cotton price changes. 展开更多
关键词 COTTON FUTURES LISTED companies STOCK PRICE relati
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