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Ultrasound-guided prostate percutaneous intervention robot system and calibration by informative particle swarm optimization

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Frontiers of Mechanical Engineering 2022年第1期17卷 18-33页

作者： Jiawen YAN Bo PAN yili FU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

Applying a robot system in ultrasound-guided percutaneous intervention is an effective approach for prostate cancer diagnosis and *** limited space for robot manipulation restricts structure volume and *** this paper,an 8-degree-of-freedom robot system is proposed for ultrasound probe manipulation,needle positioning,and needle insertion.A novel parallel structure is employed in the robot system for space saving,structural rigidity,and collision *** particle swarm optimization method based on informative value is proposed for kinematic parameter identification to calibrate the parallel structure *** method identifies parameters in the modified kinematic model stepwise according to parameter *** experiments prove that the robot system can realize motions needed in *** applying the calibration method,a reasonable,reliable forward kinematic model is built,and the average errors can be limited to 0.963 and 1.846 mm for insertion point and target point,respectively.

关键词： ultrasound image guidance prostate percutaneous intervention parallel robot kinematics identification particle swarm optimization informative value

Development of a novel hand-eye calibration for intuitive control of minimally invasive surgical robot

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Frontiers of Mechanical Engineering 2022年第3期17卷 91-108页

作者： Yanwen SUN Bo PAN yili FU State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin150001China

Robotic-assisted surgical system has introduced a powerful platform through dexterous instrument and hand-eye coordination intuitive *** knowledge of laparoscopic vision is a crucial piece of information for robot-assisted minimally invasive surgery focusing on improved surgical *** the transformation with respect to the laparoscope and robot slave arm frames using hand-eye calibration is essential,which is a key component for developing intuitive control *** proposed a novel two-step modified dual quaternion for hand-eye calibration in this *** dual quaternion was exploited to solve the hand-eye calibration simultaneously and powered by an iteratively separate *** obtained hand-eye calibration result was applied to the intuitive control by using the hand-eye coordination *** simulations and experimental studies were conducted to evaluate the proposed method on our surgical robot *** extensively compared the proposed method with state-of-the-art *** demonstrate this method can improve the calibration *** effectiveness of the intuitive control algorithm was quantitatively evaluated,and an improved hand-eye calibration method was *** relationship between laparoscope and robot kinematics can be established for intuitive control.

关键词： minimally invasive surgery hand-eye calibration intuitive control surgical robot dual quaternion

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水平井电缆射孔振动安全性分析

石油机械 2024年第8期52卷 41-50页

作者：周鑫钟柳军简屹林陈益丽梁爽西南石油大学机电工程学院成都大学机械工程学院

水平井射孔时,射孔弹爆炸会产生巨大的冲击波作用于管柱自身,并造成严重的管柱振动行为,甚至造成管柱与管串工具的损坏。为了研究水平井电缆射孔振动安全性,基于Hamilton原理,考虑射孔爆轰载荷的衰减、管柱-井壁的接触碰撞、超深井高温... 详细信息

水平井射孔时,射孔弹爆炸会产生巨大的冲击波作用于管柱自身,并造成严重的管柱振动行为,甚至造成管柱与管串工具的损坏。为了研究水平井电缆射孔振动安全性,基于Hamilton原理,考虑射孔爆轰载荷的衰减、管柱-井壁的接触碰撞、超深井高温高压环境和管柱自生约束等因素的影响,建立了水平井电缆射孔纵-横-扭耦合非线性动力学模型。使用Newmark-β法对系统非线性离散方程组进行求解,并编制了相应的MATLAB计算程序。采用西南地区H1实例井井深结构和射孔参数,利用非线性振动模型探究了射孔轰爆载荷在超深井高温高压环境下对水平井电缆射孔纵-横-扭耦合振动的影响机理。研究结果表明:射孔枪过长会增大其横向位移、截面位移和振动幅值,过短则会导致管柱所受到Mises应力增大,故在考虑射孔枪安全使用和抑制振动的前提下,射孔枪长度20 m左右最合适。当射孔弹装药量超过20 g时,管柱所受到的最大Mises应力已经超过了其自身的极限应力值,在保证高效率射孔和管柱安全的前提下,射孔弹装药量应控制在15~20 g之间,这一参数与西南地区龙马溪组H2/3实例井使用的装药量相符合。研究结果可以为特定井的射孔弹装药量提供建议。

关键词：水平井电缆射孔爆轰压力场动态响应应力传播振动安全

Valuable Data Extraction for Resistivity Imaging Logging Interpretation

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Tsinghua Science and Technology 2020年第2期25卷 281-293页

作者： yili Ren Renbin Gong Zhou Feng Meichao Li Institute of Computer Application Technology PetroChina Research Institute of Petroleum Exploration and Development(RIPED)Beijing 100083China Department of Well Logging&Remote Sensing Technology of RIPED Beijing 100083China

Imaging logging has become a popular means of well logging because it can visually represent the lithologic and structural characteristics of *** manual interpretation of imaging logging is affected by the limitations of the naked eye and experiential *** a result,manual interpretation accuracy is ***,it is highly useful to develop effective automatic imaging logging interpretation by machine *** imaging logging is the most widely used technology for imaging *** this paper,we propose an automatic extraction procedure for the geological features in resistivity imaging logging *** procedure is based on machine learning and achieves good results in practical *** that the existence of valueless data significantly affects the recognition effect,we propose three strategies for the identification of valueless data based on binary *** compare the effect of the three strategies both on an experimental dataset and in a production environment,and find that the merging method is the best performing of the three *** effectively identifies the valueless data in the well logging images,thus significantly improving the automatic recognition effect of geological features in resistivity logging images.

关键词： machine learning binary classification multiclass classification outlier detection imaging logging

Investigating the Effects of Greenhouse Vegetable Cultivation on Soil Fertility in Lhasa, Tibetan Plateau

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Chinese Geographical Science 2020年第3期30卷 456-465页

作者： WANG Zhaofeng GONG Dianqing ZHANG yili Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing100049China Chinese Acad-emy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

The area of land utilized for growing vegetables in greenhouses has expanded rapidly on the Tibetan Plateau over recent decades. However, the effects of greenhouses on soil fertility as well as variations in these effects between the plateau and plain remain unclear on the Tibetan Plateau. This study assessed the effects of vegetable greenhouses in the vicinity of Lhasa, using open field soil as a control. A total of 92 plough layer(0-20 cm depth) soil samples including 54 from greenhouses and 38 from open fields were taken, and soil pH, electrical conductivity(EC), total soluble salt(TS), soil organic matter(SOM), total nitrogen(TN), available phosphorus(AP), and available potassium(AK) were measured. The results reveal that, soil pH was lower 1.0 units in greenhouses than that in open field. TS was higher 82% and AP was higher 160% overall. Similarly, SOM and TN were higher 32% and 46%, respectively, while AK changed slightly at a higher 1% rate. Results also show that soil properties varied depending on cultivation time and vegetable types. Overall, pH continuously decreased with cultivation time while other soil fertility indicators reached a maximum value after nine years of cultivation before starting to decrease. The effect of leafy vegetable planting on soil was slight overall, while the impact of fruits on soil was more serious. Compared with changes in plain greenhouse soil fertility measured across the eastern China, the effects of greenhouses on soil in Lhasa remain relatively limited;and the change in the degree of soil fertility was lower and the extreme values of soil fertility occurred later in Lhasa.

关键词： facility agriculture soil nutrient imbalance soil environment Lhasa Tibetan Plateau

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中小出口跨境电商企业知识产权问题研究

北方经贸 2024年第1期 94-97页

作者：缪鹤兵张义丽苏州市职业大学商学院江苏苏州215104 帝目自动化设备(苏州)有限公司江苏苏州215127

中小出口跨境电商企业在开展跨境业务的过程中,面对知识产权问题屡屡碰壁,这对企业的运营产生负面影响甚至产生严重威胁,知识产权侵权及被侵权问题越来越成为中小出口跨境电商企业“头疼”的问题。为降低中小出口跨境电商企业的产权风险... 详细信息

中小出口跨境电商企业在开展跨境业务的过程中,面对知识产权问题屡屡碰壁,这对企业的运营产生负面影响甚至产生严重威胁,知识产权侵权及被侵权问题越来越成为中小出口跨境电商企业“头疼”的问题。为降低中小出口跨境电商企业的产权风险,政府应积极完善产权的制度环境,跨境电商行业协会应发挥产权专业服务的突出作用,企业自身应提升产权规划的能力,三方面形成合力。

关键词：出口跨境电商知识产权风险防范

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思维导图联合Mini-CEX在胸外科健康评估教学中的应用

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护理学杂志 2024年第11期39卷 81-85页

作者：秦小芬李懿丽文爱媛柯雅娟海南医学院附属海南医院胸外科海南海口570311 海南医学院附属海南医院护理部海南海口570311

目的探讨思维导图联合迷你临床演练评估在胸外科实习护生健康评估教学中的应用效果。方法方便取样法选取在胸外科实习的大专护生59人,按时间段分为对照组30人、观察组29人。对照组按常规实施临床带教;观察组采取思维导图联合迷你临床演... 详细信息

目的探讨思维导图联合迷你临床演练评估在胸外科实习护生健康评估教学中的应用效果。方法方便取样法选取在胸外科实习的大专护生59人,按时间段分为对照组30人、观察组29人。对照组按常规实施临床带教;观察组采取思维导图联合迷你临床演练评估教学法实施临床带教。连续6周后评价效果。结果观察组批判性思维能力、健康评估能力及学习效果自我评价得分显著优于对照组(均P<0.05)。结论思维导图联合迷你临床演练评估教学法用于胸外科大专实习护生健康评估能力教学,可培养护生的批判性思维能力,提高健康评估的教学效果。

关键词：护生大专胸外科临床实习健康评估思维导图迷你临床演练评估临床教学

麦洼牦牛MFSD4A基因克隆及组织表达分析

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华北农学报 2024年第2期39卷 174-183页

作者：胡莲刘益丽赵迪王泽宁江明锋西南民族大学青藏高原动物遗传资源保护与利用教育部和四川省重点试验室四川成都610041 西南民族大学畜牧兽医学院四川成都610041

旨在克隆麦洼牦牛MFSD4A基因序列并阐明其在不同组织中的表达模式,分析MFSD4A互作蛋白mRNA表达水平及其相关性,确定MFSD4A蛋白的亚细胞定位,为后续MFSD4A在牦牛睾丸生长发育调控研究中提供理论依据。以4头健康麦洼牦牛的心、肝、脾、肺... 详细信息

旨在克隆麦洼牦牛MFSD4A基因序列并阐明其在不同组织中的表达模式,分析MFSD4A互作蛋白mRNA表达水平及其相关性,确定MFSD4A蛋白的亚细胞定位,为后续MFSD4A在牦牛睾丸生长发育调控研究中提供理论依据。以4头健康麦洼牦牛的心、肝、脾、肺、肾、肌肉、脂肪、臀肌、背部肌肉、睾丸、结肠组织作试验材料,用RT-PCR技术克隆麦洼牦牛MFSD4A基因CDS序列并对其进行生物信息学分析;利用RT-qPCR技术检测MFSD4A基因在心、肝、脾、肺、肾、臀肌、背部肌肉、脂肪、睾丸、淋巴等10个组织中的表达及与其互作蛋白的相关性;构建pEGFP-MFSD4A融合质粒转染牛肾细胞系(MDBK)探究MFSD4A蛋白的亚细胞定位情况。结果表明,麦洼牦牛MFSD4A基因CDS区全长为1 530 bp,编码509个氨基酸,理论等电点(pI)为8.66,具有12个跨膜结构域,属于碱性跨膜蛋白;RT-qPCR结果显示,MFSD4A mRMA在麦洼牦牛各组织中差异表达,且在睾丸组织中表达量最高,与MFSD9、CBY1、INHBA、UNC93A、SVOP、ID1在睾丸组织中的表达量呈极显著正相关,推测MFSD4A基因可能与牦牛睾丸的生长发育调控有关;构建pEGFP-MFSD4A融合质粒转染牛肾细胞(MDBK)后的荧光定位显示该蛋白主要定位于细胞核。

关键词：牦牛 MFSD4A 基因克隆互作蛋白分析亚细胞定位

我国中部六省农业经济韧性与农业高质量发展的耦合协调分析

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黑龙江科学 2024年第7期15卷 11-13页

作者：马伊俐吴新静信阳学院商学院河南信阳464000

基于2012-2021年我国中部六省的面板数据,采用熵权法测算六省农业经济韧性与农业高质量发展的耦合协调值。结果表明,河南省、湖北省、湖南省、安徽省、江西省的耦合协调度较高,山西省的耦合协调度较低,存在人才流失等问题。中部六省的... 详细信息

基于2012-2021年我国中部六省的面板数据,采用熵权法测算六省农业经济韧性与农业高质量发展的耦合协调值。结果表明,河南省、湖北省、湖南省、安徽省、江西省的耦合协调度较高,山西省的耦合协调度较低,存在人才流失等问题。中部六省的农业经济韧性与农业高质量发展水平耦合协调度尚不能协调一致,还存在农业经济韧性相对落后于农业高质量发展的情况,为此应从强化顶层设计、提高农业经济韧性及促进现代科学技术发展等方面推动农业的高质量发展、可持续发展。

关键词：中部六省农业经济韧性农业高质量发展产业体系生产体系经营体系