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Median nerve neuropathy after flexor pollicis longus tendon reconstruction:A case report
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作者 Ji Woong Ho Young-Keun Lee 《World Journal of Clinical Cases》 2025年第27期74-80,共7页
BACKGROUND To treat flexor pollicis longus(FPL)muscle function loss,the 4th flexor digitorum superficialis(FDS)to the FPL tendon transfer is preferred as a reconstruction method.Various complications can occur during ... BACKGROUND To treat flexor pollicis longus(FPL)muscle function loss,the 4th flexor digitorum superficialis(FDS)to the FPL tendon transfer is preferred as a reconstruction method.Various complications can occur during transfer.However,median nerve neuropathy has not been reported yet.We present a case of median nerve neuropathy caused by irritation of suture knots of the 4th FDS to the FPL tendon transfer with a review of the literature.CASE SUMMARY A 52-year-old male patient presented with paresthesia along median nerve distribution of right hand after tendon transfer.He complained of right thumb flexion limitation due to FPL function loss so authors performed the 4th FDS to FPL transfer using Pulvertaft weave technique.FPL function loss was due to adhesion resulting from repeated surgery of radius shaft.He had a history of radius shaft open fracture 9 years ago and nonunion 7 years ago.During surgery,FPL muscle was severely adhered and indistinguishable.However,tendon continuity remained intact.After tendon transfer,he experienced paresthesia along median nerve distribution upon movement of thumb.He was diagnosed with median nerve neuropathy caused by irritation of tendon suture knots.Exploration was then performed.The median nerve was irritated by suture knots of transferred tendon.Thus,knots were removed.Twelve months later,he demonstrated thumb flexion of 80°.Additionally,median nerve neuropathy symptoms fully resolved.CONCLUSION Median nerve neuropathy can occur after tendon transfer from irritation of suture knots.Covering knots using surrounding tissue is recommended. 展开更多
关键词 Tendon transfer Flexor tendon median nerve NEUROPATHY Case report
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Numerical simulation 0n the influence of different median strip types in the separated highway subgrade cross section on the transport law of wind-sand flow
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作者 ZHANG Jing LI Shengyu +1 位作者 SUN Yunlong XIA Tian 《Journal of Mountain Science》 2025年第5期1707-1722,共16页
To mitigate the sand burial of highways in sandy regions,a separated subgrade design was widely adopted in the embankments of high-grade highways,but the problem of sand deposition on subgrade slopes and pavements sti... To mitigate the sand burial of highways in sandy regions,a separated subgrade design was widely adopted in the embankments of high-grade highways,but the problem of sand deposition on subgrade slopes and pavements still happens frequently.Based on the theory of wind-sand two-phase flow,this paper constructed a three-dimensional model of the separated subgrade,the wind-sand flow transport law around the subgrade with varying median strip widths and concave depths was simulated by Fluent software.After comparison and analysis of seven subgrade models,the flow field distribution,wind speed horizontal variation,and erosion-deposition characteristics were investigated.The findings are as follows:(1)The width of the median strip in the separated subgrade had significant influences on the wind-sand flow.The smooth passage of wind-sand flow over the road surface was facilitated with the increase of the median strip width.However,sand deposition in the median strip happened.It can lead to secondary sand damage of downwind subgrade and increase the work load of road sand removal for subsequent maintenance.(2)The obstruction to airflow and sand accumulation was aggravated with greater concave depth of the median strip.Therefore,it is advisable to minimize the concave depth of the median strip in case of more sand damage.(3)A median strip width exceeding 12 m(possibly without guardrails)for an integral embankment without enough road land is recommended.Conversely,median strip width of over 40 m for separate subgrade with unrestricted land is suggested.(4)In the case of sand deposition in the existing separated subgrade,the median strip can be filled by sand deposition or other materials,then was covered with gravel to form a flat ground like Gobi smooth surface,which can let the wind-blown sand flow pass through the subgrade section without sand deposition. 展开更多
关键词 Highway engineering Separated subgrade median strip Numerical simulation Embankment wind-sand flow
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Aneurysm rupture in median arcuate ligament syndrome leading to duodenal stenosis: A case report
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作者 Tomohiro Tanikawa Keisuke Miyake +12 位作者 Mayuko Kawada Katsunori Ishii Takashi Fushimi Noriyo Urata Nozomu Wada Ken Nishino Mitsuhiko Suehiro Miwa Kawanaka Hidenori Shiraha Ken Haruma Hiroyasu Fujiwara Tomoki Yamatsuji Hirofumi Kawamoto 《World Journal of Clinical Cases》 2025年第25期87-93,共7页
BACKGROUND A 56-year-old female presented with acute abdominal pain due to a ruptured pseudoaneurysm associated with median arcuate ligament syndrome(MALS),a rare condition caused by the compression of the celiac arte... BACKGROUND A 56-year-old female presented with acute abdominal pain due to a ruptured pseudoaneurysm associated with median arcuate ligament syndrome(MALS),a rare condition caused by the compression of the celiac artery by the median arcuate ligament(MAL),potentially leading to ischemia,aneurysm formation,and rupture.CASE SUMMARY Computed tomography revealed a retroperitoneal hematoma,celiac artery stenosis,and two aneurysms in the inferior pancreaticoduodenal artery.Hemo-stasis was achieved using transcatheter arterial embolization.However,15 days after embolization,the patient developed duodenal stenosis,manifesting as gastric distension and nausea without abdominal pain.Endoscopy revealed mucosal edema and luminal narrowing of the duodenum.Conservative treatment was ineffective,and the patient underwent MAL transection and gastrojejun-ostomy.She recovered uneventfully,and follow-up at 4 months showed complete resolution of duodenal stenosis and no recurrence.CONCLUSION This case highlights the importance of the early diagnosis and multidisciplinary management of MALS. 展开更多
关键词 median arcuate ligament syndrome Retroperitoneal hemorrhage Duodenal stenosis Inferior pancreaticoduodenal artery aneurysm Transcatheter arterial embolization Case report
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耦合优化蚁群算法与P-Median model的选址模型设计 被引量:2
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作者 顾梓程 胡新玲 《现代电子技术》 北大核心 2024年第3期109-114,共6页
为节省城建部门对于公共体育设施的投入成本以及提高城市人民生活质量,以运动场所优化选址为例,提出一种新型设施选址模型。该模型主要基于P-Median model(最小化阻抗模型)根据需求点数量从全部候选设施选址中选择设施空间位置,让用户... 为节省城建部门对于公共体育设施的投入成本以及提高城市人民生活质量,以运动场所优化选址为例,提出一种新型设施选址模型。该模型主要基于P-Median model(最小化阻抗模型)根据需求点数量从全部候选设施选址中选择设施空间位置,让用户达到离自己最近设施距离成本总和最小的目的,对选址的基本原则和实际情况提出要求,构造目标函数用于优化后蚁群算法求解进行选址工作。优化蚁群算法实现基于Python语言模块,通过改进蚁群原始信息素,提升原有算法的收敛速度,求出目标函数最优解,可以很好地模拟对于运动场所的选址。用二者耦合进行优势互补所设计的选址模型来搜寻研究区蚁群信息素浓度残留最大的栅格像元,从而确定未被已有设施点服务半径覆盖的最佳设施点建立位置。实验结果表明,该新型选址模型相较于最小化阻抗模型与最大化覆盖模型,新增优化设施点使整体服务半径覆盖率分别高出10.42%和6.95%,适合求解较为精确且小规模空间下的选址问题。 展开更多
关键词 蚁群算法 P-median model 选址模型 GIS 运动场所 位置分配 PYTHON
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Median-of-Means方法在偏度系数中的应用 被引量:2
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作者 刘鹏飞 杨文婷 +1 位作者 张茹 周勤 《统计研究》 CSSCI 北大核心 2024年第4期153-160,共8页
传统偏度系数的定义涉及样本均值和三阶矩,使其对离群值十分敏感。本文在偏度系数的估计中引入Median-of-Means方法,提出偏度系数的新估计量,并证明其相合性和渐近正态性。此外,基于经验似然方法提出一种新的偏度系数检验统计量,证明其... 传统偏度系数的定义涉及样本均值和三阶矩,使其对离群值十分敏感。本文在偏度系数的估计中引入Median-of-Means方法,提出偏度系数的新估计量,并证明其相合性和渐近正态性。此外,基于经验似然方法提出一种新的偏度系数检验统计量,证明其渐近性质并进行数值模拟。结果表明,本文提出的估计量具有一定稳健性,检验统计量表现也优于传统方法。最后将所提出的估计与检验方法应用于实际数据分析发现,估计结果比较稳健,进一步表明原有的偏度系数估计方法并不适用。 展开更多
关键词 偏度系数 median-of-Means 经验似然 渐近正态性 数值模拟
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The Effects of Laser Therapy in Treating Hypertrophic Scars and Keloids after Median Sternotomy:A Scoping Review 被引量:1
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作者 Laura Schianchi Fabrizio Vaira +9 位作者 Massimo Chessa Serena Francesca Flocco Arianna Magon Gianluca Conte Karina Geraldina Zuniga Olaya Giacomo Bortolussi Erika Cioffi Matteo Riccardo Di Nicola Santo Raffaele Mercuri Rosario Caruso 《Congenital Heart Disease》 SCIE 2024年第4期363-374,共12页
Background:Hypertrophic scars and keloids,common complications following median sternotomy for cardiac surgery,significantly impact patient quality of life due to their aesthetic and symptomatic burden.Recent advanceme... Background:Hypertrophic scars and keloids,common complications following median sternotomy for cardiac surgery,significantly impact patient quality of life due to their aesthetic and symptomatic burden.Recent advancements in laser therapy have made it a prominent option for managing these complex scars,yet a com-prehensive understanding of its efficacy is lacking.The aim of this scoping review is to explore the effects of laser therapy in managing hypertrophic scars and keloids after median sternotomy.Methods:This scoping review ana-lyzed studies up to February 2024 from databases including PubMed,EMBASE,CINAHL,Scopus,Web of Science,and the Cochrane Library.We included any study that assessed laser therapy’s effects on hypertrophic scars and keloids following median sternotomy.Studies were selected based on predefined inclusion criteria with-out publication year,design,or origin restrictions.Results:Six studies met the inclusion criteria,involving a total offive RCTs and one review.These studies primarily tested 585 and 595-nm pulsed dye laser(PDL)treatments,focusing on scar appearance,patient symptoms,and treatment satisfaction.Most studies reported significant improvements in scar height reduction and patient symptom relief after treatment,with mixed results for scar erythema and elasticity.Adverse events were generally mild and transient.Conclusions:Laser therapy offers a beneficial approach for improving the appearance and symptoms of hypertrophic scars and keloids post-median sternotomy.However,further research is necessary to optimize treatment parameters and explore the long-term psychosocial impacts of this therapy.This review highlights the need for more comprehensive studies to establish standardized treatment protocols and evaluate their effectiveness. 展开更多
关键词 Laser therapy hypertrophic scars KELOIDS median sternotomy cardiac surgery pulsed dye laser scar management
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Comparing Short-Term Outcomes of Right Mini-Thoracotomy and Median Sternotomy for Isolated Left Atrial Myxoma Excision
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作者 Munjerin Refat Synthee Satyajit Sharma +8 位作者 Md. Abir Tazim Chowdhury Munama Magdum Muhit Abdullah Md. Zafar-Al-Nimari Md. Ahaduzzaman Dewan Iftakher Reza Chowdhury Saikat Dasgupta Prasanta Kumar Chandra Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第10期157-165,共9页
Background: Left atrial myxoma (LAM) is the most common heart tumor in adults, requiring prompt surgical removal to prevent complications like valvular obstruction or embolization. Objectives: This study aimed to comp... Background: Left atrial myxoma (LAM) is the most common heart tumor in adults, requiring prompt surgical removal to prevent complications like valvular obstruction or embolization. Objectives: This study aimed to compare early postoperative outcomes between two surgical approaches—right mini-thoracotomy and median sternotomy—for the removal of isolated left atrial myxoma. Methods: We conducted a prospective observational study at the Department of Cardiac Surgery, National Heart Foundation Hospital & Research Institute (NHFH&RI), Mirpur, Dhaka, from March 2017 to August 2019. Twenty-eight patients undergoing surgery for isolated left atrial myxoma were included. The surgical approach was determined by the operating surgeon. We analyzed outcomes like intubation time, Intensive Care Unit (ICU) stay, pain levels (Visual Analogue Scale score), and overall hospital stay using SPSS. Statistical significance was set at p Results: Patients in the right mini-thoracotomy group had longer mean intubation times (11.43 vs. 5.93 hours, p Conclusion: Despite longer intubation and ICU times, the right mini-thoracotomy approach offers a minimally invasive alternative for isolated left atrial myxoma excision, with favorable outcomes overall. 展开更多
关键词 Left Atrial Myxoma Mini-Thoracotomy median Sternotomy Cardiac Surgery
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Simultaneous Compression of the Celiac Trunk, Superior Mesenteric Artery, and Renal Arteries by the Median Arcuate Ligament: About One Case
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作者 Siddick Oumar Kenza Fathallah +5 位作者 Hassan Ahmed Aicha Merzem Hasnaa Belgadir Omar Amriss Nadia Moussali Naima El Benna 《Open Journal of Medical Imaging》 2024年第3期106-113,共8页
Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insert... Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insertion of the diaphragmatic crura or an abnormally high origin of the celiac trunk from the aorta can cause compression of the celiac artery. Usually, patients with MALS are asymptomatic. Computed tomography (CT) angiography of the abdomen is the main imaging modality to confirm the diagnosis. The coexistence of celiac trunk and superior mesenteric artery compression by the median arcuate ligament is rarely described in the literature. To our knowledge, until now, a simultaneous combination of three abdominal vascular compressions by the median arcuate ligament has never been described. From this case, we report a simultaneous compression of the celiac trunk, superior mesenteric artery, and renal arteries by the median arcuate ligament. 展开更多
关键词 median Arcuate Ligament Syndrome (MALS) Celiac Trunk Compression Superior Mesenteric Artery and Renal Arteries Compression Computed Tomography Angiography
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多重median图及其性质
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作者 王广富 《数学进展》 CSCD 北大核心 2014年第3期360-364,共5页
设u,u和叫是图G的三个顶点,如果点z同时位于这三个点两两之间的最短路上,则称z为u,v和w的一个median.图G称为多重median图,如果G中任意三个顶点都至少有一个median.研究多重median图的若干基本性质,结果表明多重median图都是二部的,其... 设u,u和叫是图G的三个顶点,如果点z同时位于这三个点两两之间的最短路上,则称z为u,v和w的一个median.图G称为多重median图,如果G中任意三个顶点都至少有一个median.研究多重median图的若干基本性质,结果表明多重median图都是二部的,其收缩图是多重median图,最后证明了两个多重median图的积图仍是多重median图. 展开更多
关键词 最短路 median 多重median 积图
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Adaptive Threshold Median Filter for Multiple-Impulse Noise 被引量:4
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作者 姜波 黄炜 《Journal of Electronic Science and Technology of China》 2007年第1期70-74,共5页
Attenuating the noises plays an essential role in the image processing. Almost all the traditional median filters concern the removal of impulse noise having a single layer, whose noise gray level value is constant. I... Attenuating the noises plays an essential role in the image processing. Almost all the traditional median filters concern the removal of impulse noise having a single layer, whose noise gray level value is constant. In this paper, a new adaptive median filter is proposed to handle those images corrupted not only by single layer noise. The adaptive threshold median filter (ATMF) has been developed by combining the adaptive median filter (AMF) and two dynamic thresholds. Because of the dynamic threshold being used, the ATMF is able to balance the removal of the multiple-impulse noise and the quality of image. Comparison of the proposed method with traditional median filters is provided. Some visual examples are given to demonstrate the performance of the proposed filter. 展开更多
关键词 median filter adaptive median filter (AMF) adaptive threshold median filter(ATMF) multiple-impulse noise image processing
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Central administration of Orphanin FQ inhibits GnRH secretion by ORL1 receptor in the median eminence of freely moving ovariectomized rats 被引量:1
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作者 安晓飞 贺明 +2 位作者 冯异 冯昊 余江毅 《Neuroscience Bulletin》 SCIE CAS CSCD 2009年第1期1-6,共6页
Objective This study aimed to investigate the possible role of Orphanin FQ(OFQ) in the regulation of hypothalamic gonadotropin-releasing hormone(GnRH) secretion. Methods The method of push-pull perfusion and radioimmu... Objective This study aimed to investigate the possible role of Orphanin FQ(OFQ) in the regulation of hypothalamic gonadotropin-releasing hormone(GnRH) secretion. Methods The method of push-pull perfusion and radioimmunoassay(RIA) were adopted to examine the secretory profile of GnRH in the median eminence(ME) in freely moving ovariectomized(OVX) rats after intracerebroventricular(icv) injection of OFQ and/or [Nphe1]NC(1-13)NH2(NC13),a competitive antagonists of the opioid receptor-like 1 receptor(ORL1 recep... 展开更多
关键词 Orphanin FQ gonadotropin-releasing hormone luteinizing hormone median eminence
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库区水上应急救助设施多因素P-median选址模型 被引量:2
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作者 张进峰 刘永森 +2 位作者 牟军敏 董唏中 王晓鸥 《中国安全科学学报》 CAS CSCD 北大核心 2016年第11期163-168,共6页
为提高库区水域的水上应急救助能力和救助设施选址决策的科学性,在深入分析救助设施最优选址问题的基础上,引入应急需求点安全风险权重系数,以应急救助点覆盖半径为约束条件,建立同时考虑救助时间和安全风险的P-median水上应急救助设施... 为提高库区水域的水上应急救助能力和救助设施选址决策的科学性,在深入分析救助设施最优选址问题的基础上,引入应急需求点安全风险权重系数,以应急救助点覆盖半径为约束条件,建立同时考虑救助时间和安全风险的P-median水上应急救助设施选址模型。将所建模型应用于甘肃刘家峡库区水上应急救助设施选址问题,采用免疫算法求解模型,得到应急救助点最优选址方案。结果表明,用免疫算法能有效求得P-median应急救助设施选址模型的最优解。 展开更多
关键词 P-median 水上应急救助 选址 库区 安全风险
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贪心算法求解k-median问题 被引量:1
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作者 肖进杰 范辉 +1 位作者 郭玉刚 程大鹏 《计算机工程与应用》 CSCD 北大核心 2006年第3期57-58,68,共3页
文章讨论了用贪心算法解k-m edian问题以及其试验结果。首先提出了一个解k-m edian问题的简单贪心算法,然后对求解质量和求解的近似性能比进行了探讨。主要讨论了公制空间和非公制空间初始解的产生,用贪心算法解k-m edian问题以及全局... 文章讨论了用贪心算法解k-m edian问题以及其试验结果。首先提出了一个解k-m edian问题的简单贪心算法,然后对求解质量和求解的近似性能比进行了探讨。主要讨论了公制空间和非公制空间初始解的产生,用贪心算法解k-m edian问题以及全局最优解的计算。试验结果表明:贪心算法解公制空间的k-m edian问题效果要好于解非公制空间的k-m edian问题;用贪心算法解公制空间和非公制空间k-m edian问题都能得到较好的结果。 展开更多
关键词 k-median 贪心算法 公制空间 非公制空间 初始解
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使用MIP优化器求解p-median问题——以学校选址为例 被引量:2
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作者 孔云峰 王新刚 王震 《河南大学学报(自然科学版)》 CAS 北大核心 2014年第6期725-730,共6页
通常采用启发式或元启发式算法求解区位问题.随计算机性能的大幅提升和整型规划(MIP)算法的持续改进,基于MIP优化器求解大规模区位问题模型已具有可行性.以有容量约束的县级市规模义务学校选址为例,构建p-median问题指派规划和一般整型... 通常采用启发式或元启发式算法求解区位问题.随计算机性能的大幅提升和整型规划(MIP)算法的持续改进,基于MIP优化器求解大规模区位问题模型已具有可行性.以有容量约束的县级市规模义务学校选址为例,构建p-median问题指派规划和一般整型规划模型,采用多个免费和商业优化器进行模型求解.案例测试表明:常见MIP优化器能高效地获得最优解或高质量可行解;与指派规划模型相比,构建p-median问题的一般整型规划模型更容易求解;商业MIP优化器明显优于开源软件. 展开更多
关键词 区位选址 p-median问题 MIP优化器
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基于Median函数的分段回归模型及其在生物学上的应用 被引量:1
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作者 于向鸿 肖阳 《生物数学学报》 CSCD 2012年第3期529-536,共8页
在生物学科研工作中,经常会遇到因变量和自变量之间存在着多种不同的趋势,分段回归模型可以很好的拟合变量间这种非线性趋势.本文介绍了基于Median函数的分段回归模型,可以同时对各项回归参数和转折点进行估计,最后,本文结合生物学上的... 在生物学科研工作中,经常会遇到因变量和自变量之间存在着多种不同的趋势,分段回归模型可以很好的拟合变量间这种非线性趋势.本文介绍了基于Median函数的分段回归模型,可以同时对各项回归参数和转折点进行估计,最后,本文结合生物学上的实例运用SAS统计软件进行了分段回归模型的拟合. 展开更多
关键词 分段回归模型 非线性回归 median函数 SAS程序
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K-median问题贪心近似算法的分析与实验 被引量:1
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作者 肖进杰 谢青松 刘晓华 《计算机工程》 CAS CSCD 北大核心 2008年第22期213-214,217,共3页
讨论K-median问题的贪心近似算法及其在实际计算中的表现。提出一个解K-median问题的贪心算法,证明该算法的近似度为O(In(n/k)),通过实验证明该贪心算法在实际应用当中可以取得较好的效果,大约有90%的客户能被距离其最近、次近和第三近... 讨论K-median问题的贪心近似算法及其在实际计算中的表现。提出一个解K-median问题的贪心算法,证明该算法的近似度为O(In(n/k)),通过实验证明该贪心算法在实际应用当中可以取得较好的效果,大约有90%的客户能被距离其最近、次近和第三近的设备服务。 展开更多
关键词 K-median问题 贪心算法 近似算法
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一类median问题的近似算法研究 被引量:1
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作者 王继强 《山东大学学报(理学版)》 CAS CSCD 北大核心 2006年第4期1-3,共3页
利用Lin和Vitter的过滤思想研究了完全图的赋权median问题,并给出了一个近似算法.此算法可在最小化破坏背包约束的条件下求得问题的一个近似比为1+ε(ε>0)的解.
关键词 median 过滤规划 集合覆盖 近似算法
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k-median问题反向贪心随机算法 被引量:2
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作者 王守强 《计算机科学》 CSCD 北大核心 2012年第7期232-236,共5页
k-median问题的近似算法研究一直是计算机科学工作者关注的焦点。基于均衡限制条件,利用反向贪心策略,给出求解该问题的随机近似算法。证明该算法以较大的概率满足其近似性能比的期望值为(3+O(ln(ln(k)/α))。该算法的时间复杂度为O([k... k-median问题的近似算法研究一直是计算机科学工作者关注的焦点。基于均衡限制条件,利用反向贪心策略,给出求解该问题的随机近似算法。证明该算法以较大的概率满足其近似性能比的期望值为(3+O(ln(ln(k)/α))。该算法的时间复杂度为O([kαln(k)]2(n+m)),其中n和m分别代表设施集合以及客户点集的大小。最后,通过计算机实验验证了k-median问题的反向贪心算法的实际计算效果。 展开更多
关键词 k-median 随机算法 反向贪心 近似性能比
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Adaptive median threshold algorithm used in FDIS of DSSS receivers 被引量:2
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作者 Weijun Yang Chaojie Zhang +2 位作者 Xiaojun Jin Zhonghe Jin Tieshan Yuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期11-18,共8页
For direct sequence spread spectrum (DSSS) receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression (FDIS). The key is... For direct sequence spread spectrum (DSSS) receivers, the capability of rejecting narrow-band interference can be significantly improved by a process of frequency-domain interference suppression (FDIS). The key issue of this process is how to determine a threshold to eliminate interference in the frequency domain, which has been extensively studied. However, these previous methods are tedious or very complex. A simple and ef- ficient algorithm based on medians is proposed. The elimination threshold is only related to the median by a scale factor, which can be obtained by the numerical analysis. Simulation results show that the algorithm provides excellent narrow-band interfer- ence suppression while only slightly degrading the signal-to-noise ratio (SNR). A one-pass algorithm using logarithmic segmentation is further derived to estimate medians with low computational complexity. Finally, the FDIS is implemented in a field programmable gate array (FPGA) of Xilinx. Experiments are carried out by connecting the FDIS FPGA to a DSSS receiver, and the results show that the receiver has an effective countermeasure for a 60 dB interference-to-signal ratio (ISR). 展开更多
关键词 direct sequence spread spectrum (DSSS) discreteFourier transform (DFT) frequency-domain interference suppres-sion (FDIS) adaptive median threshold one-pass approximatemedians.
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近似k-median分类属性数据聚类
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作者 赵恒 张高煜 《计算机工程》 CAS CSCD 北大核心 2007年第8期66-67,70,共3页
数据挖掘中解决分类属性数据聚类的算法有很多种,但大多数基于划分的方法得到的聚类中心一般不是数据集中的实际数据对象,缺乏实际的物理意义,有时会导致某一聚类为空。该文研究了近似k-median的求解算法,用数据的近似中值来代替模式进... 数据挖掘中解决分类属性数据聚类的算法有很多种,但大多数基于划分的方法得到的聚类中心一般不是数据集中的实际数据对象,缺乏实际的物理意义,有时会导致某一聚类为空。该文研究了近似k-median的求解算法,用数据的近似中值来代替模式进行聚类,提出了分类属性数据的近似k-median聚类算法,克服了一般基于划分的可分类属性数据聚类中所遇到的问题,仿真实验证明该算法有效。 展开更多
关键词 数据挖掘 近似k-median聚类 分类属性数据
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