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Study on the dynamic behavior of herringbone gear structure of marine propulsion system powered by double-cylinder turbines

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Science China(Technological Sciences) 2022年第3期65卷 611-630页

作者： XU jianghai JIAO ChunXiao ZOU DongLin TA Na RAO ZhuShi State Key Laboratory of Mechanical System and Vibration Institute of VibrationShock and NoiseShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

Propulsion systems powered by double-cylinder turbines(DCT)are widely used in large-scale ***,the nonlinear instability leads to hidden dangers associated with the safe operation,and there is a lack of theoretical and systematic research on this *** on the gear transmission principle and non-Newtonian thermal elastohydrodynamic lubrication(EHL)theory,a torsional model of a two-stage herringbone system forced by unsymmetrical load is *** nonlinear and time-varying factors of meshing friction,meshing stiffness,and gear pair backlash are included in the model,and multiple meshing states,including single-and double-sided impact are *** nonlinear phenomena of the dynamic system are explored and the effects of the unsymmetrical load on the system stability are *** results indicate that the stability of the gear system is improved,and that the back-sided impact gradually disappears with the increases of load ratio between the two inputs and the input load ***,it is found that the gear pairs on the low-load side experience more severe vibration than those on the high-load ***,the stability of the gear pairs decreases along the power transmission path of the multistage gear *** results of this research will be useful when making predictions of the stability of such systems and in the optimization of the load parameters.

关键词： DCT propulsion system DI-SO herringbone gears unsymmetrical load nonlinear instability mechanism

Dent Resistance for Automobile Body Panels

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 903-911页

作者： LU Hongzhou MA Mingm YOU jianghai LI Zhigang China Automotive Engineering Research Institute Chongqing 400039 China Southwest Aluminum （Group） Co. Ltd Chongqing 401326 China

Dent resistance of automobile body panels is an important property for automobile design and manufacture, but the study on this aspect is not still profound. This study is to summarize the testing methods and physical significations of static and dynamic dent resistance of automobile body panels combined with the author＇s study, and to analyze the dent behaviors in the round. Several influence factors on dent resistance are expatiated including the mechanical properties of materials, stress states after forming, bake hardening ability, modulus, methods of testing, and structure of specimens and so on. The automotive lightweight and application of high strength steel sheets and aluminum alloys sheets are analyzed, and the significance of testing of dent resistance, especially for dynamic dent resistance of auto-panels, and the finite element simulation analysis are emphasized. To explain the physical phenomenon of dent behaviors, the latest and concerned study results are also discussed. According to this study, a dent resistance test and evaluation standard of Society of Automotive Engineers of China for automotive body panel is presented and is being carried out, and an industry conference is hold to discuss the working-out of the standard, a primary schedule of this standard is confirmed now. The study can guide the further testing and study of dent resistant of auto-panels.

关键词： dent resistance dent resistance test automobile body panels dynamic dent resistance stiffness

深度学习重建算法在肝脏肿瘤患者CT检查中的应用进展

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影像科学与光化学 2024年第4期42卷 385-391页

作者：冯俏全江海程留慧河南中医药大学河南郑州450000 河南中医药大学第一附属医院河南郑州450000

肝脏肿瘤在临床较为常见,尤其是肝癌患者,是消化系统常见的恶性肿瘤之一,已严重威胁到人们的身心健康。基于卷积神经网络的深度学习重建算法是CT重建算法的一种新兴技术,逐渐趋于成熟并且在体模、临床中已有相关实践。与滤波反投影法、... 详细信息

肝脏肿瘤在临床较为常见,尤其是肝癌患者,是消化系统常见的恶性肿瘤之一,已严重威胁到人们的身心健康。基于卷积神经网络的深度学习重建算法是CT重建算法的一种新兴技术,逐渐趋于成熟并且在体模、临床中已有相关实践。与滤波反投影法、迭代重建算法相比,深度学习重建算法可以降低辐射剂量、实现有效降噪,优化细微结构的显示,提升主观诊断信心等。影像组学可以高通量地提取高维影像特征,深度学习重建算法可以提高影像组学特征的临床应用可信性。本文对深度学习重建算法在肝脏肿瘤中的相关研究展开综述,旨在进一步理解深度学习重建算法的临床进展,并为后续研究积累证据。

关键词：深度学习肝肿瘤重建算法 X线计算机体层摄影

Schwann cells originating from skin-derived precursors promote peripheral nerve regeneration in rats

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Neural Regeneration Research 2014年第18期9卷 1696-1702页

作者： Ping Zhang Xiaocheng Lu jianghai Chen Zhenbing Chen Department of Orthopedics Wuhan Women and Children Health Care Center Department of Hand Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and Technology

Artificial guidance channels containing Schwann cells can promote the regeneration of injured peripheral nerve over long distances. However, primary Schwann cells are not suitable for autotransplantation. Under specific conditions, skin-derived progenitors can be induced to dif- ferentiate into Schwann cells. Therefore, adult rat dorsal skin （dermis）-derived progenitors were isolated and induced to differentiate with DMEM/F12 containing B27, neuregulin 1, and for- skolin. Immunofluorescence staining and reverse transcription polymerase chain reaction （RT- PCR） confirmed that the resultant cells were indeed Schwann cells. Artificial guidance channels containing skin-derived progenitors, Schwann cells originating from skin-derived progenitors, or primary Schwann cells were used to bridge 5 mm sciatic nerve defects. Schwann cells originating from skin-derived progenitors significantly promoted sciatic nerve axonal regeneration. The sig- nificant recovery of injured rat sciatic nerve function after the transplantation of Schwann cells originating from skin-derived progenitors was confirmed by electromyogram. The therapeutic effect of Schwann cells originating from skin-derived progenitors was better than that of skin-de- rived progenitors. These findings indicate that Schwann cells originating from skin-derived precursors can promote peripheral nerve regeneration in rats.

关键词： nerve regeneration skin-derived precursors Schwann cells peripheral nerve injury celltransplantation NSFC grant neural regeneration

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邻域信息加权的最小二乘投影双支持向量聚类

电子测量技术 2024年第12期47卷 59-70页

作者：王顺霞黄成泉罗森艳杨贵燕蔡江海贵州民族大学数据科学与信息工程学院贵阳550025 贵州民族大学工程技术人才实践训练中心贵阳550025

针对最小二乘投影双支持向量聚类(LSPTSVC)算法未充分利用样本邻域之间的潜在信息、实用性不强等问题,本文提出了一种高效的邻域信息加权的最小二乘投影双支持向量聚类算法。首先引入相对密度概念充分提取数据集中同类数据点之间的局部... 详细信息

针对最小二乘投影双支持向量聚类(LSPTSVC)算法未充分利用样本邻域之间的潜在信息、实用性不强等问题,本文提出了一种高效的邻域信息加权的最小二乘投影双支持向量聚类算法。首先引入相对密度概念充分提取数据集中同类数据点之间的局部相似性信息,然后计算该点的相对权重,最后利用该权重获得数据点的加权平均值,来更好的反映同类样本的几何结构。实验结果验证了所提算法的有效性,结果表明本文算法在相似的计算复杂度下,相比现有方法取得了更好的聚类准确性,且在真实世界的医学数据集的实际应用中表现出良好的聚类性能。

关键词：邻域信息相对权重最小二乘双支持聚类

An Indicator System for Assessing Soil Erosion in the Loess Plateau Gully Regions:A Case Study in the Wangdonggou Watershed,China

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Pedosphere 2004年第1期14卷 37-44页

作者： NIShao-Xiang MAGuo-Bin WEIYu-Chun jianghai-Fu CollegeofGeographicalScience NanjingNormalUniversityNanjing210097（China）

The Wangdonggou Watershed on the Loess Plateau in China was selected as the study area to develop a model for soil erosion assessments. Using the data collected at 20 sampling sites all tentatively selected indicators were assessed against their corresponding erosion intensity through a correlation analysis. Eight highly correlated indicators were then chosen for the soil erosion assessment. In addition, threshold limits to delineate the class size for these indicators and weights to rank them were determined. Next, a grading model incorporating the selected indicators class rating and their associated weights was developed and verified by an on site evaluation of the soil erosion intensity in the study area. Results of the verification showed that the overall accuracy of the indicator system for assessing soil erosion in the Loess Plateau gully regions could reach 85%.

关键词： assessment indicator loess plateau soil erosion watershed

Adaptive Fuzzy Sliding Mode Controller with Nonlinear Observer for Redundant Manipulators Handling Varying External Force

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Journal of Bionic Engineering 2016年第4期13卷 600-611页

作者： Jun He Minzhou Luo Qingqing Zhang jianghai Zhao Linsen Xu Department of Automation School of Information Science of Technology University of Science and Technology of China HeJei 230026 China Institute of Advanced Manufactcturing and Technology Hefei Institute of Physical Science Chinese Academy of Sciences Changzhou 213164 China School of Mechanical and Electrical Engineering Hohai University Changzhou 213264 China School of Engineering Science University of Seience and Technology of China Hefei 230026 China

An Adaptive Fuzzy Sliding Mode Controller with Nonlinear Observer （AFSMCO） for the redundant robotic manipulator is proposed in this paper. This approach could achieve a precise trajectory tracking for a robot manipulator in the presence of uncertainties and disturbances. Primarily, a suitable observer using the recursive algorithm is presented for an accurate estima- tion of external disturbances caused by the varying external force. Secondly, the adaptive fuzzy logic is designed to approximate the parameters of the sliding mode controller （AFSMC） to avoid chattering in real time. Moreover, it is shown using the Lyapunov theory that the tracking error asymptotically converges to zero. Finally, the effectiveness of the proposed control approach and theoretical discussion are demonstrated by simulation results on a 7-1ink robot and tested on a 7-DOF manipulator platform.

关键词： fuzzy logic adaptive control redundant manipulators nonlinear observer

临床触诊阴性的乳腺良性结节麦默通微创手术与传统手术的临床疗效对比

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系统医学 2024年第10期9卷 108-111页

作者：龚龙伟李江海黄鹄江南大学附属医院甲乳外科江苏无锡214122

目的探讨麦默通微创旋切技术在实际的触诊阴性乳腺良性结节治疗过程中的运用。方法回顾性选取江南大学附属医院甲乳外科于2019年6月—2021年6月收治的100例临床触诊阴性的乳腺良性结节患者的临床资料,按照手术方式的不同分为观察组(麦... 详细信息

目的探讨麦默通微创旋切技术在实际的触诊阴性乳腺良性结节治疗过程中的运用。方法回顾性选取江南大学附属医院甲乳外科于2019年6月—2021年6月收治的100例临床触诊阴性的乳腺良性结节患者的临床资料,按照手术方式的不同分为观察组(麦默通微创旋切术)与对照组(传统开放手术),每组50例,对比分析两组患者手术指标、术后乳腺外形满意度、术后原位复发率、术后切口内血肿形成等观察指标。结果观察组手术时长、切口长度、伤口愈合期、住院时间、疼痛视觉模拟评分均优于对照组,差异有统计学意义(P均0.05)。观察组切口内血肿发生率低于对照组,差异有统计学意义(P<0.05)。结论超声引导下的麦默通微创旋切术在治疗临床触诊阴性乳腺良性结节应用上具有手术时长短、切口长度短、术后疼痛轻、伤口愈合时间短、术后并发症少、住院时间短、术后乳腺外形满意度高等技术优势。

关键词：麦默通旋切临床触诊阴性乳腺良性结节超声

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美军人工智能技术发展态势

国防科技 2024年第2期45卷 23-32页

作者：杨筱梁江海束哲吴集国防科技大学国防科技战略研究智库湖南长沙410073

为全面深入把握美军人工智能发展态势,从发展战略布局、项目投资分析、学术产出水平等方面对美军人工智能技术发展态势进行系统研究。通过分析可知,美军已形成全方位、体系化的战略布局,通过持续高位投资不断推进人工智能技术创新与军... 详细信息

为全面深入把握美军人工智能发展态势,从发展战略布局、项目投资分析、学术产出水平等方面对美军人工智能技术发展态势进行系统研究。通过分析可知,美军已形成全方位、体系化的战略布局,通过持续高位投资不断推进人工智能技术创新与军事应用,在顶尖成果、原创成果方面仍占据相对优势。美军把人工智能技术作为提升未来联合作战能力的重要发力点,多措并举,大力推动人工智能技术发展和军事应用,或将对世界未来发展产生深远影响。

关键词：人工智能美军发展态势