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Kick Off Maritime Boundary Disputes: Published Maps, Not Drawn With Agreement, Compatible to the International Law? 预览
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作者 Emete Gozuguzelli 《国际关系与外交:英文版》 2019年第9期418-430,共13页
Issues concerning on the continental shelf and in the exclusive economic zone between Turkey and the Greek Cypriot Administration (GCA) have been more controversial. This study answers the following questions:(a) What... Issues concerning on the continental shelf and in the exclusive economic zone between Turkey and the Greek Cypriot Administration (GCA) have been more controversial. This study answers the following questions:(a) What is the main arguments of the Parties?(b) How the exclusive economic zone could be declared?(c) Does median line applicable to the delimitation law without taken the related circumstances in the Eastern Mediterranean?(d) Can any maps on claimed exclusive economic zone borders publish without maritime boundary delimitation agreements, officially? The main intent of the study is to evaluate the different perspectives of the Parties on maritime delimitation and to evaluate the boundaries of the exclusive economic zone bounded by the European Union on the European Asia and Europe Africa Interconnected Cable Network Projects maps in the Eastern Mediterranean. 展开更多
关键词 EXCLUSIVE economic zone (EEZ) European Union DELIMITATION MEDIAN line the Eastern Mediterranean the GREEK Cypriot Administration (GCA) Turkey
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应用上唇人中区皮瓣联合下唇Abbe瓣修复双侧唇裂继发鼻唇畸形 预览
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作者 林广民 游彩莲 +3 位作者 曹宁 郑美莲 汤逸颜 吴锦鸿 《中国整形与重建外科(英文)》 2019年第1期10-13,共4页
Objective To explore an ideal method for the correction of the secondary nasolabial deformities of bilateral cleft lip. Methods From January 2013 to December 2018 ,repairing nose and lip in median of the median upper ... Objective To explore an ideal method for the correction of the secondary nasolabial deformities of bilateral cleft lip. Methods From January 2013 to December 2018 ,repairing nose and lip in median of the median upper lip flap and lower lip Abbe flap in 13 patients with secondary nasolabial deformity of cleft lip, implanting artificial nose prosthesis when necessary. Results All the flaps were survived and nose appearance was greatly improved. The shape of the upper lip turned more similar to normal. Coordination between upper lip and lower lip was appropriate. Conclusion The median upper lip flap combined with lower lip Abbe flap to repair the secondary nasolabial deformities of bilateral cleft lip is effective . Goo d cosmetic results can be obtained. 展开更多
关键词 Bilateral CLEFT LIP Nasolabial DEFORMITY The median upper LIP FLAP Abbe FLAP
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基于互差跳跃算法的签到系统研究与实现 预览
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作者 王青青 周国祥 +2 位作者 戎皓 石雷 张翠翠 《合肥工业大学学报:自然科学版》 CAS 北大核心 2019年第7期912-917,共6页
针对传统签到方式耗时且繁琐,文章研究并实现了一个基于互差跳跃算法的签到系统。该系统使用百度地图应用编程接口(application programming interface,API)获取签到者位置信息,基于中位数的互差跳跃算法判断签到者所在位置是否正确。... 针对传统签到方式耗时且繁琐,文章研究并实现了一个基于互差跳跃算法的签到系统。该系统使用百度地图应用编程接口(application programming interface,API)获取签到者位置信息,基于中位数的互差跳跃算法判断签到者所在位置是否正确。算法以中位数附近一定范围的互差均值作为基准,以相邻数据互差与基准的比值作为异常门槛系数,根据系数值对已签到用户位置信息的可信度进行判断,从而确定用户的真实出勤状态。该系统目前已应用于某高校课堂考勤,实际应用效果证明该系统拥有较高的准确率,可以满足签到需求,有很好的实用性。 展开更多
关键词 中位数 签到 百度地图 经纬度 可疑值判别
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Chitosan tubes enriched with fresh skeletal muscle fibers for delayed repair of peripheral nerve defects 预览
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作者 Alessandro Crosio Benedetta Elena Fornasari +5 位作者 Giovanna Gambarotta Stefano Geuna Stefania Raimondo Bruno Battiston Pierluigi Tos Giulia Ronchi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期1079-1084,共6页
Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump... Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump of chronically transected nerves;moreover,Schwann cells undergo atrophy,losing their ability to sustain regeneration.In the present study,to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth,we combined the use of an effective conduit(a chitosan tube)with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers).This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction.Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft,considered the“gold standard”technique for nerve reconstruction.Since hollow tubes not always lead to good results after long defects(>20 mm),we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps,as muscle fibers create a favorable three-dimensional environment and release trophic factors.All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number:864/2016/PR)on September 14,2016. 展开更多
关键词 tubulization Schwann cells SCAFFOLD tissue engineering NERVE reconstruction morphometrical analyses GRASPING test secondary repair MEDIAN NERVE NERVE REGENERATION
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基于综合滤波算法与模糊PID控制的温度控制系统 预览
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作者 李幸 周凤星 严保康 《仪表技术与传感器》 CSCD 北大核心 2019年第3期77-81,96共6页
为满足某氮氧化物(NO_x)传感器精度测试系统“传感器温度应维持在750℃以确保测试结果的准确性”的要求,提出了一种综合滤波算法(以中位值、滑动平均、消抖滤波法及平移不变量小波去噪法为基础)用来消除噪声对温度信号的干扰,并辅以模... 为满足某氮氧化物(NO_x)传感器精度测试系统“传感器温度应维持在750℃以确保测试结果的准确性”的要求,提出了一种综合滤波算法(以中位值、滑动平均、消抖滤波法及平移不变量小波去噪法为基础)用来消除噪声对温度信号的干扰,并辅以模糊自适应PID控制以维持传感器温度在750℃左右。实验证明:该综合算法可消除大部分噪声的干扰,能使传感器温度稳定在750±1℃,满足了检测系统的需要。 展开更多
关键词 中位值 滑动平均 消抖滤波法 平移不变量小波去噪 模糊自适应PID控制
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Sample geometric mean versus sample median in closed form framework of seismic reliability evaluation: a case study comparison 预览
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作者 M.Abyani B.Asgarian M.Zarrin 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第1期187-201,共15页
Earthquake engineers have made a lot of efforts to derive a comprehensive set of closed form expressions for performance evaluation of frames, which are already presented in guidelines such as SAC/FEMA. These analytic... Earthquake engineers have made a lot of efforts to derive a comprehensive set of closed form expressions for performance evaluation of frames, which are already presented in guidelines such as SAC/FEMA. These analytical expressions have been developed to estimate the annual probability of exceeding a limit state. In the process of such seismic assessments, some essential assumptions are adopted to simplify the process. One of these fundamental assumptions declares that drift demand at any seismic intensity level follows a lognormal distribution around its median. To investigate the validity of this assumption, this paper describes a case study of the types of errors that could be produced by using the sample median as the central tendency. Based on the Maximum Likelihood Estimation method as well as other statistical evidence, this paper proposes the use of the sample geometric mean instead of the sample median for the central tendency. Further, the results of seismic reliability evaluations of 4 sample frames are compared based on utilizing both the geometric mean and the sample median. In this process, both first and second order power law fits of the hazard curve are implemented to compare the effects of hazard estimation and the selection of the central tendency on the final results. It is observed in the application example that the sample geometric mean could lead to more accurate results. 展开更多
关键词 seismic reliability closed-form expression SAC/FEMA limit state MEDIAN GEOMETRIC mean
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Modified contralateral C7 nerve transfer: the possibility of permitting ulnar nerve recovery is confirmed by 10 cases of autopsy 预览
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作者 Guang-Hui Hong Jing-Bo Liu +3 位作者 Yu-Zhou Liu Kai-Ming Gao Xin Zhao Jie Lao 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第8期1449-1454,共6页
Contralateral C7 nerve transfer surgery is one of the most important surgical techniques for treating total brachial plexus nerve injury. In the traditional contralateral C7 nerve transfer surgery, the whole ulnar ner... Contralateral C7 nerve transfer surgery is one of the most important surgical techniques for treating total brachial plexus nerve injury. In the traditional contralateral C7 nerve transfer surgery, the whole ulnar nerve on the paralyzed side is harvested for transfer, which completely sacrifices its potential of recovery. In the present, novel study, we report on the anatomical feasibility of a modified contralateral C7 nerve transfer surgery. Ten fresh cadavers (4 males and 6 females) provided by the Department of Anatomy, Histology, and Embryology at the Medical College of Fudan University, China were used in modified contralateral C7 nerve transfer surgery. In this surgical model, only the dorsal and superficial branches of the ulnar nerve and the medial antebrachial cutaneous nerve on the paralyzed side (left) were harvested for grafting the contralateral (right) C7 nerve and the recipient nerves. Both the median nerve and deep branch of the ulnar nerve on the paralyzed (left) side were recipient nerves. To verify the feasibility of this surgery, the distances between each pair of coaptating nerve ends were measured by a vernier caliper. The results validated that starting point of the deep branch of ulnar nerve and the starting point of the medial antebrachial cutaneous nerve at the elbow were close to each other and could be readily anastomosed. We investigated whether the fiber number of donor and recipient nerves matched one another. The axons were counted in sections of nerve segments distal and proximal to the coaptation sites after silver impregnation. Averaged axon number of the ulnar nerve at the upper arm level was approximately equal to the sum of the median nerve and proximal end of medial antebrachial cutaneous nerve (left: 0.94:1;right: 0.93:1). In conclusion, the contralateral C7 nerve could be transferred to the median nerve but also to the deep branch of the ulnar nerve via grafts of the ulnar nerve without deep branch and the medial antebrachial cutaneous nerve. The advantage over traditiona 展开更多
关键词 NERVE REGENERATION brachial plexus avulsion injury NERVE transfer CONTRALATERAL C7 NERVE MODIFIED surgery deep branch of ULNAR NERVE median NERVE medial antebrachial cutaneous NERVE hand function neural REGENERATION
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Reinnervation of spinal cord anterior horn cells after median nerve repair using transposition with other nerves 预览
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作者 Yu-Song Yuan Su-Ping Niu +8 位作者 You-Lai Yu Pei-Xun Zhang Xiao-Feng Yin Na Han Ya-Jun Zhang Dian-Ying Zhang Hai-Lin Xu Yu-Hui Kou Bao-Guo Jiang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第4期699-705,共7页
Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves,the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair dist... Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves,the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair distal nerve and target muscle tissue and restore muscle motor function.To observe the effect of nerve regeneration and motor function recovery after several types of nerve transposition for median nerve defect(2 mm),30 Sprague-Dawley rats were randomly divided into sham operation group,epineurial neurorrhaphy group,musculocutaneous nerve transposition group,medial pectoral nerve transposition group,and radial nerve muscular branch transposition group.Three months after nerve repair,the wrist flexion test was used to evaluate the recovery of wrist flexion after regeneration of median nerve in the affected limbs of rats.The number of myelinated nerve fibers,the thickness of myelin sheath,the diameter of axons and the cross-sectional area of axons in the proximal and distal segments of the repaired nerves were measured by osmic acid staining.The ratio of newly produced distal myelinated nerve fibers to the number of proximal myelinated nerve fibers was calculated.Wet weights of the flexor digitorum superficialis muscles were measured.Muscle fiber morphology was detected using hematoxylin-eosin staining.The cross-sectional area of muscle fibers was calculated to assess the recovery of muscles.Results showed that wrist flexion function was restored,and the nerve grew into the distal effector in all three nerve transposition groups and the epineurial neurorrhaphy group.There were differences in the number of myelinated nerve fibers in each group.The magnification of proximal to distal nerves was 1.80,3.00,2.50,and 3.12 in epineurial neurorrhaphy group,musculocutaneous nerve transposition group,medial pectoral nerve transposition group,and radial nerve muscular branch transposition group,respectively.Nevertheless,axon diameters of new nerve fibers,cross-sectional areas of axons,thicknesses of myelin sheath,wet 展开更多
关键词 NERVE REGENERATION TRANSPOSITION repair MEDIAN NERVE functional remodeling muscle atrophy surgical intervention peripheral NERVE injury neural REGENERATION
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A new auxiliary information based cumulative sum median control chart for location monitoring
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作者 Shahid HUSSAIN Li-xin SONG +1 位作者 Shabbir AHMAD Muhammad RIAZ 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第4期554-570,共17页
Control charts are commonly used tools in statistical process control for the detection of shifts in process parameters. Shewhart-type charts are efficient for large shift values, whereas cumulative sum(CUSUM) charts ... Control charts are commonly used tools in statistical process control for the detection of shifts in process parameters. Shewhart-type charts are efficient for large shift values, whereas cumulative sum(CUSUM) charts are effective in detecting medium and small shifts. Control chart use commonly assumes that data are free of outliers and parameters are known or correctly estimated based on an in-control process. In practice, these assumptions are not often true because some processes occasionally have outliers. Monitoring the location parameter is usually based on mean charts, which are seriously affected by violations of these assumptions. In this paper we propose several CUSUM median control charts based on auxiliary variables, and offer comparisons with their corresponding mean control charts. To monitor the location parameter, we examined the performance of mean and median control charts in the presence and absence of outliers. Both symmetric and non-symmetric processes were studied to examine the properties of the proposed control charts to monitor the location parameter using CUSUM control charts. We used different run length measures to study in-control and out-of-control performances of CUSUM charts. Results revealed that our proposed control charts perform much better than the traditional charts in the presence of outliers. A real application of our study was provided using data on concrete compressive strength as it relates to the quality of cement manufacturing. 展开更多
关键词 AVERAGE RUN length AUXILIARY information CUSUM CONTROL charts LOCATION parameter MEDIAN CONTROL charts
Relationship between sonographically measured median nerve cross-sectional area and presence of peripheral neuropathy in diabetic subjects 预览
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作者 Fredrick Andrew Attah Christianah Mopelola Asaleye +3 位作者 Adeleye Dorcas Omisore Babatope Ayodeji Kolawole Adeniyi Sunday Aderibigbe Mathew Alo 《世界糖尿病杂志:英文版(电子版)》 2019年第1期47-56,共10页
BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerve... BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerves.Median nerve is one of the peripheral nerves commonly affected in diabetic neuropathy.The median nerve size has been studied in non-Nigerian diabetic populations.In attempt to contribute to existing literature,a study in a Nigerian population is needed.AIM To evaluate the cross-sectional area(CSA)of the median nerve using B-mode ultrasonography(USS)and the presence of peripheral neuropathy(PN)in a cohort of adult diabetic Nigerians.METHODS Demographic and anthropometric data of 85 adult diabetes mellitus(DM)and 85 age-and sex-matched apparently healthy control(HC)subjects were taken.A complete physical examination was performed on all study subjects to determine the presence of PN and modified Michigan Neuropathy Screening Instrument(MNSI)was used to grade its severity.Venous blood was taken from the study subjects for fasting lipid profile(FLP),fasting blood glucose(FBG)and glycated haemoglobin(HbA1c)while their MN CSA was evaluated at a point 5 cm proximal to(5cmCATL)and at the carpal tunnel(CATL)by high-resolution Bmode USS.Data was analysed using SPSS version 22.RESULTS The mean MN CSA was significantly thicker in DM subjects compared to the HC at 5cmCATL(P<0.01)and at the CATL(P<0.01)on both sides.The presence of diabetic peripheral neuropathy(DPN)further increased the MN CSA at the CATL(P<0.05)but not at 5cmCATL(P>0.05).However,the severity of DPN had no additional effect on MN CSA 5 cm proximal to and at the CATL.There was no significant association between MN CSA and duration of DM and glycemic control.CONCLUSION Thickening of the MN CSA at 5cmCATL and CATL is seen in DM.Presence of DPN is associated with worse thickening of the MN CSA at the CATL but not at 5cmCATL.Severity of DPN,duration of DM,and glycemic control had no additional effect on the MN CSA. 展开更多
关键词 MEDIAN nerve CROSS-SECTIONAL area SONOGRAPHY DIABETICS Peripheral NEUROPATHY
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CUSUM中位数控制图设计 被引量:2
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作者 胡雪龙 周晓剑 +1 位作者 黄卫东 蒋国平 《数理统计与管理》 CSSCI 北大核心 2018年第3期469-477,共9页
针对生产过程中质量特性数据存在个别异常以及离群值的情形,采用中位数统计量(X)代替传统均值(X)统计量,提出一种累积和(Cumulative Sum,CUSUM)X控制图来监控过程均值的偏移。采用马尔科夫链方法,首先构建CUSuMx控制图的状态... 针对生产过程中质量特性数据存在个别异常以及离群值的情形,采用中位数统计量(X)代替传统均值(X)统计量,提出一种累积和(Cumulative Sum,CUSUM)X控制图来监控过程均值的偏移。采用马尔科夫链方法,首先构建CUSuMx控制图的状态转移矩阵,推导各状态的转移概率,进一步可推导出CUSUMX控制图的链长分布特性。通过最优化过程处于失控状态下的CUSUMX控制图的平均运行链长(Average Run Length,ARL)指标,获得控制图的最优决策变量和性能指标。仿真结果表明,CUSUMX控制图优于传统的休哈特(Shewhart)X以及指数加权滑动平均(Exponentially Weighted Moving Average,EWMA)X控制图,尤其针对较小的均值偏移,其性能优势更加明显。 展开更多
关键词 中位数 累积和中位数控制图 平均运行链长
一种图像自适应中值滤波算法 预览 被引量:1
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作者 刘海 《软件导刊》 2018年第5期59-61,共3页
图像在产生、传递与接收过程中,会受到外界的影响尤其是噪音的干扰,严重影响图像质量,有必要进行预处理以保证图像的正常使用。阐述了脉冲噪音理论,分析了一维与二维中值滤波原理,提出一种自适应中值滤波算法。该算法作为非线性滤波算法... 图像在产生、传递与接收过程中,会受到外界的影响尤其是噪音的干扰,严重影响图像质量,有必要进行预处理以保证图像的正常使用。阐述了脉冲噪音理论,分析了一维与二维中值滤波原理,提出一种自适应中值滤波算法。该算法作为非线性滤波算法,弥补了线性滤波算法缺陷,明显抑制了噪音,保证了原图像的信息内容。实验结果表明,这种自适应中值滤波算法在归一化均方误差(NMSE)、峰值信噪比(PSNR)、算法耗时T(s)等方面,比中值滤波算法具有一定的优势。 展开更多
关键词 图像处理 自适应 中值滤波 算法 噪音抑制
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基于中位数排序集样本的比率估计改进方法 预览
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作者 张建军 乔松珊 《长春大学学报》 2018年第4期28-33,共6页
基于中位数排序集样本提出了比率估计的一种改进方法,计算了该估计量的偏差和均方误差,分析了比率系数的优化方法,并讨论了不同抽样方法下估计量的相对效率。算例表明,正态分布下基于中位数排序集样本的改进比率估计可以提高估计效率。
关键词 中位数 排序集抽样 比率估计 改进 效率
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辅助生育与自然妊娠孕中期产前血清学筛查标记物中位数的结果分析
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作者 孙茜 许遵鹏 +1 位作者 苏洁玲 李东至 《热带医学杂志》 CAS 2018年第11期1431-1434,共4页
目的比较辅助生育受孕和自然受孕的孕妇孕中期产前血清学筛查各标记物中位数的差异。方法选择2016年12月至2017年10月间通过辅助生育技术受孕的单胎孕妇140例为辅助生育组,筛取同期孕周、年龄、体重相匹配的自然妊娠且为单胎的孕妇420... 目的比较辅助生育受孕和自然受孕的孕妇孕中期产前血清学筛查各标记物中位数的差异。方法选择2016年12月至2017年10月间通过辅助生育技术受孕的单胎孕妇140例为辅助生育组,筛取同期孕周、年龄、体重相匹配的自然妊娠且为单胎的孕妇420例为自然妊娠组,采用时间分辨荧光免疫法进行三联血清学筛查。结果比较两组孕妇各孕周阶段的甲胎蛋白(AFP)和游离雌三醇(uE3)的中位数倍数(MoM)值均接近1,差异无统计学意义(P>0.05);游离β人绒毛膜促性腺激素(free-βHCG)在辅助生育组中的MoM值小于1,而自然妊娠组MoM值大于1,差异有统计学意义(P<0.05)。结论辅助生育可能会引起各标记物中位数及MoM值的差异,建立此类人群的产前筛查指标的参考范围,引入适当的校准系数评估风险将有利于提高产前筛查的检出率。 展开更多
关键词 辅助生育 自然受孕 血清学筛查标记物 中位数
基于实时中值估计的分布式稳健滤波融合方法 预览
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作者 黄河 陈庆良 张旭 《探测与控制学报》 CSCD 北大核心 2018年第5期47-52,共6页
针对电子信息装备运动目标多源测量数据加权融合中的复杂电磁环境影响,提出了基于实时中值估计的分布式稳健滤波融合方法。该方法以稳健统计理论为基础,首先给出基于实时中值估计和匀速模型的稳健滤波方法,并将稳健滤波残差刻度应用于... 针对电子信息装备运动目标多源测量数据加权融合中的复杂电磁环境影响,提出了基于实时中值估计的分布式稳健滤波融合方法。该方法以稳健统计理论为基础,首先给出基于实时中值估计和匀速模型的稳健滤波方法,并将稳健滤波残差刻度应用于权值最优分配原则下的融合权重动态计算,最终得到稳健加权融合结果。典型运动目标实测数据测试结果表明,该方法具有较高的样本崩溃点,能有效处理含一定长度连续粗差的测量数据,且能用于弱机动情形。 展开更多
关键词 稳健 加权融合 复杂电磁环境 残差刻度 中值
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提高学生评教有效性的对策研究 预览
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作者 王晓刚 《扬州职业大学学报》 2018年第4期65-68,共4页
在文献回顾的基础上,针对学生评教在高校质量保障体系中所具备的优势及存在的问题,提出了优化对策:采用中位数取代算术平均数,以评校数据为常模,对评教数据进行标准化。同时给出了新的学生评教系统的E-R模型、数据模型以及算法设计。
关键词 评教 评校 中位数 参照物 算法
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取用水监测点的水量计算与变化趋势分析
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作者 方海泉 薛惠锋 +3 位作者 蒋云钟 万毅 周铁军 王海宁 《系统工程理论与实践》 CSSCI CSCD 北大核心 2018年第9期2390-2400,共11页
加强取用水监测是实施最严格水资源管理制度的重要举措.为了更有效地利用大量的取用水在线监测数据,需要对获取的监测数据进行预处理.本文首先提出应用中位数法与曲线拟合相结合的方法对取用水监测数据进行异常值检测,再用曲线拟合方法... 加强取用水监测是实施最严格水资源管理制度的重要举措.为了更有效地利用大量的取用水在线监测数据,需要对获取的监测数据进行预处理.本文首先提出应用中位数法与曲线拟合相结合的方法对取用水监测数据进行异常值检测,再用曲线拟合方法对异常值进行校正;其次,根据校正后得到的数据进行两个方面的分析,一方面是计算监测点的年取水量,另一方面是应用集成经验模态分解方法分析监测点的日取水量变化趋势;最后,以M市的16个自来水厂2016年取用水在线监测数据为例进行实证分析,结果表明,本文提出的中位数法与曲线拟合相结合的方法能够有效地检测异常值,进而再用曲线拟合方法能够更好地对异常值校正.根据校正后得到的数据进行分析发现81%的监测点年取水量相对2011年水利普查数据有所增加,个别监测点超出许可取水量较多,75%的监测点从春季到冬季日取水量变化为先增后减的抛物线趋势. 展开更多
关键词 监测点 监测数据 取用水量 异常值 中位数 曲线拟合 集成经验模态分解
基于流形学习的自适应反馈聚类中心确定方法 预览
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作者 李天龙 曹敏 +3 位作者 沈鑫 吴晟 吴兴蛟 周海河 《云南电力技术》 2018年第5期77-80,87共5页
K-means聚类是现行最为通用的聚类算法之一,但其在聚类过程中聚类中心不够稳定,针对这一问题,以流行聚类为依托,实现一种可以提升聚类中心稳定程度的反馈聚类方法.首先使用谱聚类对目标数据集初次聚类得到聚类集合,再根据目标集合最大... K-means聚类是现行最为通用的聚类算法之一,但其在聚类过程中聚类中心不够稳定,针对这一问题,以流行聚类为依托,实现一种可以提升聚类中心稳定程度的反馈聚类方法.首先使用谱聚类对目标数据集初次聚类得到聚类集合,再根据目标集合最大子集数动态调整参数,多次迭代后获得聚类数集合表并对表中聚类值统计,最后计算表中加权平均值确定最终聚类数目.通过一百次迭代后的数据可知,使用加权平均值得到的聚类更稳定,反馈谱聚类迭代中位数和加权平均数的使用优化了流形聚类方法. 展开更多
关键词 流形学习 反馈聚类 加权平均数 中位数
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求数据流中位数序列的算法分析 预览
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作者 陈文 王琳燕 《信息技术》 2018年第11期34-36,43共4页
中位数求法通常利用排序算法获取,其时间复杂度达到O(n*ln n)甚至O(n^2)。对于数据流,逐点利用排序法求中位数序列,时间复杂度更高,当数据量很大时,运行极其费时,文中提出利用堆结构获取数据流中位数序列的方法。描述基本思想,分... 中位数求法通常利用排序算法获取,其时间复杂度达到O(n*ln n)甚至O(n^2)。对于数据流,逐点利用排序法求中位数序列,时间复杂度更高,当数据量很大时,运行极其费时,文中提出利用堆结构获取数据流中位数序列的方法。描述基本思想,分析堆的构造方法,详细介绍算法实现过程。其时间复杂度仅为O(n*ln n),较常用的排序算法有较大的改进。最后,通过实验进一步证实该算法的优越性。 展开更多
关键词 中位数 算法 排序
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天钢棒材裙板系统控制原理 预览
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作者 王会超 《天津冶金》 CAS 2018年第4期39-41,共3页
从裙板辊道系统和裙板液压系统入手,分析了天钢俸材生产线裙板控制系统动作原理,指出俸材生产裙板系统正常运转的关键在于设置正确的抛钢位置和裙板中位停留时间。利用数学模型计算出适合天钢俸材裙板系统的抛钢位置和中位停留时间,... 从裙板辊道系统和裙板液压系统入手,分析了天钢俸材生产线裙板控制系统动作原理,指出俸材生产裙板系统正常运转的关键在于设置正确的抛钢位置和裙板中位停留时间。利用数学模型计算出适合天钢俸材裙板系统的抛钢位置和中位停留时间,应用后,实现了俸材裙板系统同时拾取两支俸材的生产模式,提高了俸材收集的稳定性和效率从而提高了俸材生产的作业率。 展开更多
关键词 棒材 裙板系统 抛钢 位置 中位 停留时间
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