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Comparison of 25-gauge sutureless vitrectomy and 20-gauge vitrectomy in the treatment of posterior capsule opacification in pseudophakic children

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1179-1183页

作者： Xiao-Ming Wu Li-xin xie Qingdao University Medical College Shandong Eye Institute

AIMTo compare the effectiveness and safety of pars plana capsulotomy and vitrectomy using 25-gauge tansconjunctival sutureless vitrectomy system and 20-gauge vitrectomy system for posterior capsule opacification (PCO) in pseudophakic *** study. Pars plana capsulotomy and vitrectomy using 25-gauge sutureless vitrectomy system was performed for PCO in the study group (32 eyes). Patients in the control group (34 eyes) underwent capsulotomy and vitrectomy using standard 20-gauge vitrectomy system, providing a comparison between 2 groups with regard to preoperative and postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), and intraoperative and postoperative complications. The two groups were performed consequentially. The patients ages ranged from 2 to 13y (means: 6.61±2.73y). Surgical technique, intraoperative and postoperative complications, visual acuity, IOP, and recurrent PCO were *** surgical procedure was performed uneventfully in all patients. Visual acuity improved significantly in both groups. BCVA improved in 22 eyes (81.5%) in the study group and in 28 eyes (87.5%) in the control group. There was no statistical difference of visual acuity that were attainable in two groups (H=0.115, P=0.909). Mean postoperative IOP showed no significant difference between the groups at 1wk. All sort of PCO were accomplished by 20-gauge system, while 25-gauge system was effective for pearls style and 2 grade of fibrous PCO, and was insufficient to grade 3 of PCO. In the study group two cases were not accomplished by 25-gauge system while 20-gauge system conquered them. Compared with the control group, mean operative time for opening and closing the sclerotomy in the study group was considerably reduced. The mean follow-up was 38.2mo (range: 8-79mo). During the follow-up period, no incision leakage, corneal edema, vitreous loss, IOL damage, retinal detachment, recurrent PCO, or other complications wer

关键词： posterior capsular opacity vitrectomy cataract children

Atomic Coherent Trapping and Properties of Trapped Atom

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Communications in Theoretical Physics 2006年第3X期46卷 556-560页

作者： YANG Guo-Jian XIA Li-xin xie Min Department of Physics Beijing Normal University Beijing 100875 China

Based on the theory of velocity-selective coherent population trapping, we investigate an atom-laser system where a pair of counterpropagating laser fields interact with a three-level atom. The influence of the parametric condition on the properties of the system such as velocity at which the atom is selected to be trapped, time needed for finishing the coherent trapping process, and possible electromagnetically induced transparency of an altrocold atomic medium, etc., is studied.

关键词： velocity selective coherent population trapping ultracold atom

Processing limit maps for the stable deformation of dieless drawing

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 330-337页

作者： Yong He Xue-feng Liu Jian-xin xie Hong-gang Zhang Key Laboratory for Advanced Materials Processing （MOE） University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Tin bronze wires were produced by dieless drawing. The effects of heating power, the distance between cooler and heater as well as feeding speed on the diameter, the temperature field, and the deformation region profile of the wires were investigated. The results indi-cated that each processing parameter exhibited both lower and upper limits of stable deformation based on the criterion of stable deformation with the diameter fluctuation of ±0.05 mm. Both the temperature and its gradient of the deformation region increased with increasing heating power under stable deformation, but decreased with an increase in feeding speed. As the distance between cooler and heater increased, the temperature of the deformation region increased and the slope of the deformation region profile decreased. The processing limit map of sta-ble deformation exhibited a closed curve and the unstable deformation consisted of wire breakage and diameter fluctuations.

关键词： tin bronze wire dieless drawing processing parameters turning method

Effect of trace HA on microstructure, mechanical properties and corrosion behavior of Mg-2Zn-0.5Sr alloy

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Journal of Materials Science & Technology 2018年第2期34卷 299-310页

作者： Jian-xing Li Yuan Zhang Jing-Yuan Li Jian-xin xie School of Materials Science and Engineering University of Science and Technology Beijing Institute for Advanced Materials and Technology University of Science and Technology Beijing

Effect of the addition of trace HA particles into Mg-2Zn-0.5Sr on microstructure, mechanical properties, and bio-corrosion behavior was investigated in comparison with pure Mg. Microstructures of the Mg-2Zn-0.5Sr-xHA composites （x= 0, 0.1 and 0.3 wt%） were characterized by optical microscopy （OM）, scanning electron microscopy （SEM） equipped with energy dispersion spectroscopy （EDS） and X-ray diffraction （XRD）. Results of tensile tests at room temperature show that yield strength （YS） of Mg- 2Zn-0.5Sr/HA composites increases significantly, but the ultimate tensile strength （UTS） and elongation decrease with the addition of HA particles from 0 up to 0.3 wt%. Bio-corrosion behavior was investigated by immersion tests and electrochemical tests. Electrochemical tests show that corrosion potential （Ecorr） of Mg-2Zn-0.5Sr/HA composites significantly shifts toward nobler direction from -1724 to -1660 mVscE and the corrosion current density decreases from 479.8 to 280.8 ***^-2 with the addition of HA particles. Immersion tests show that average corrosion rate of ***/HA composites decreases from 11.7 to 9.1 mm/year with the addition of HA particles from 0 wt% up to 0.3 wt%. Both microstructure and mechanical properties can be attributed to grain refinement and mechanical bonding of HA particles with second phases and α-Mg matrix. Bio-corrosion behavior can be attributed to grain refinement and the formation of a stable and dense CaHPO4 protective film due to the adsorption of Ca^2＋ on HA particles. Our analysis shows that the Mg-2Zn-0.5Sr/0.3HA with good strength and corrosion resistance can be a good material candidate for biomedical applications.

关键词： Magnesium alloys Bio-composites Hydroxyapatite Microstructure Mechanical property Bio-corrosion behavior

High-precision gyro-stabilized control of a gear-driven platform with a floating gear tension device

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Frontiers of Mechanical Engineering 2021年第3期16卷 487-503页

作者： Xianliang JIANG Dapeng FAN Shixun FAN xin xie Ning CHEN College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

This study presents an improved compound control algorithm that substantially enhances the antidisturbance performance of a gear-drive gyro-stabilized platform with a floating gear tension *** tension device can provide a self-adjustable preload to eliminate the gap in the meshing ***,the weaker gear support stiffness and more complex meshing friction are also induced by the tension device,which deteriorates the control accuracy and the ability to keep the aim point of the optical sensors isolated from the platform *** modeling and compensation of the induced complex nonlinearities are technically challenging,especially when base motion *** aim of this research is to cope with the unmeasured disturbances as well as the uncertainties caused by the base lateral ***,the structural properties of the gear transmission and the friction-generating mechanism are analyzed,which classify the disturbances into two categories:Time-invariant and time-varying ***,a proportional-integral controller is designed to eliminate the steady-state error caused by the time-invariant disturbance.A proportional multiple-integral-based state augmented Kalman filter is proposed to estimate and compensate for the time-varying disturbance that can be approximated as a polynomial *** effectiveness of the proposed compound algorithm is demonstrated by comparative experiments on a gear-drive pointing system with a floating gear tension device,which shows a maximum 76%improvement in stabilization precision.

关键词： inertially stabilized platform floating gear tension device nonlinear friction disturbance compensation proportional multiple-integral observer

Millennial climate changes since MIS 3 revealed by element records in deep-sea sediments from northern South China Sea

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Chinese Science Bulletin 2014年第8期59卷 776-784页

作者： xin xie Hong-Bo Zheng Pei-Jun Qiao State Key Laboratory of Marine Geology Tongji University School of Geography Science Nanjing Normal University

High resolution elemental records in core MD05-2903 from the northern South China Sea were obtained from XRF scanning and grain size and mineral component *** K/Ti curve reveals climate changes since MIS 3 on a millennial scale,representing one of the best such records so far from deep-sea sediments of the South China *** compared our K/Ti record with other climate records from high latitude ice cores and from East Asia stalagmites,variations in the K/Ti record show some typical saw-shaped features of rapid climate changes in the Northern *** size analysis reveals a close relationship between variations in K/Ti and in the fine end-member grain *** analysis confirms that high K/Ti layers were dominated by K-rich weathering minerals,especially illite,while low K/Ti layers contain low illite but high abundance of Ti-rich heavy ***,the K/Ti record reflects changes in the input and deposition of fine weathering minerals and heavy minerals in the northern South China Sea region during stadials and *** elemental changes were largely controlled by variations in rainfall,erosion,and fluvial transportation induced by East Asia Monsoon.

关键词：深海沉积物中国南海气候变化 MIS 元素显示 X射线衍射分析矿物风化

LQTTrack:Multi-Object Tracking by Focusing on Low-Quality Targets Association

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Computers, Materials & Continua 2024年第10期81卷 1449-1470页

作者： Suya Li Ying Cao Hengyi Ren Dongsheng Zhu xin xie Henan Key Laboratory of Big Data Analysis and Processing School of Computer and Information EngineeringHenan UniversityKaifeng475001China College of Information Science and Technology&Artificial Intelligence Nanjing Forestry UniversityNanjing210037China School of Computer Nanjing University of Posts and TelecommunicationsNanjing210023China

Multi-object tracking(MOT)has seen rapid improvements in recent ***,frequent occlusion remains a significant challenge in MOT,as it can cause targets to become smaller or disappear entirely,resulting in lowquality targets,leading to trajectory interruptions and reduced tracking *** from some existing methods,which discarded the low-quality targets or ignored low-quality target ***,with a lowquality association strategy(LQA),is proposed to pay more attention to low-quality *** the association scheme of LQTTrack,firstly,multi-scale feature fusion of FPN(MSFF-FPN)is utilized to enrich the feature information and assist in subsequent data ***,the normalized Wasserstein distance(NWD)is integrated to replace the original Inter over Union(IoU),thus overcoming the limitations of the traditional IoUbased methods that are sensitive to low-quality targets with small sizes and enhancing the robustness of low-quality target ***,the third association stage is proposed to improve the matching between the current frame’s low-quality targets and previously interrupted trajectories from earlier frames to reduce the problem of track fragmentation or error tracking,thereby increasing the association success rate and improving overall multi-object tracking *** experimental results demonstrate the competitive performance of LQTTrack on benchmark datasets(MOT17,MOT20,and DanceTrack).

关键词： Low-quality targets association strategy feature fusion multi-object tracking tracking-by-detection

Engine universal characteristic modeling based on improved ant colony optimization

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 26-35页

作者： Chen Fuen Jiang Shihui xie xin Chen Longhan Lan Yubin School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Mechanical Engineering Oakland UniversityRochesterMI 48309USA College of Engineering South China Agricultural UniversityGuangzhou 510642China

There have been some mathematics methods to model farm vehicle engine universal characteristic mapping(EUCM).Nevertheless,any of different mathematics methods used would possess its own strengths and *** a result,these modeling methods about EUCM are not the same among the most vehicle *** order to obtain a better robustness EUCM,an improved ant colony optimization was introduced into a traditional cubic surface regression method for modeling *** on this method,the test data were regressed into a three-dimensional cubic surface,after that it was cut by some equal specific fuel consumption(ESFC)planes,more than twenty two-dimensional ESFC equations were ***,the engine speed in every ESFC equation was discretized to obtain a set of ESFC points,and this set of ESFC points was linked into a closed curve by a given sequence via the improved ant colony *** order to improve the modeling speed,dimensionality reduction and discretization methods were *** addition,a corresponding simulation platform was also developed to obtain an optimal system *** were 48000 simulation search tests carried out on the platform,and the major parameters of the algorithm were *** this way the EUCM was established *** contrast with other methods,as a result of the application of the novel bionic intelligent algorithm,it has better robustness,less distortion and higher calculating speed,and it is available for both gasoline engines and diesel engines.

关键词： engines universal characteristics improved ant colony algorithm genetic algorithm cubic surface regression

Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces fabricated by double rolling

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1170-1175页

作者： Xi-yong Wang Xue-feng Liu Wen-jiang Zou Jian-xin xie School of Materials Science and Engineering University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology Beijing Key Laboratory for Advanced Materials Processing Ministry of Education) University of Science and Technology Beijing

Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces were fabricated by double rolling. The two surface morphologies of double-rolled copper foils are quite different, and the surface roughness values are 61 and 1095 nm, respectively. The roughness value of matt surface can meet the requirement for bonding the resin matrix with copper foils used for flexible printed circuit boards, thus may omit traditional roughening treatment; the microstructure of double-rolled copper foils demonstrates an obviously asymmetric gradient feature. From bright surface to matt surface in thickness direction, the average grain size first increases from 2.3 to 7.4 μm and then decreases to 3.6 μm; compared with conventional rolled copper foils, the double-rolled copper foils exhibit a remarkably increased bending fatigue life, and the increased range is about 16.2%.

关键词： copper foils rolling surfaces gradient structure fatigue of materials