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Evaluation of New Commercially Available Metal Artifact Reduction (MAR) Algorithm on Both Image Quality and Relative Dosimetry for Patients with Hip Prosthesis or Dental Fillings

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2017年第2期6卷 124-138页

作者： Vicky w. Huang Kirpal Kohli Medical Physics BC Cancer Agency Fraser Valley Centre Surrey Canada

Streaking artifacts on computed tomography (CT) images are caused by high density materials such as hip prosthesis, surgical clips and dental fillings. The artifacts can lead to compromised clinical outcome due to the inability to differentiate tumor volume and the uncertainties in dose calculation. The goals of our study are to evaluate how GE’s smart metal artifact reduction (MAR) algorithm impacts image quality on phantoms and dosimetry on head and neck patients with dental fillings and pelvic patients with hip prosthesis. Treatment plans calculated on the MAR and non-MAR datasets with the same beam arrangements and fluence are compared. Dose differences between the MAR and non-MAR datasets are not significant. However, substantial reductions of metal artifacts are observed when MAR algorithm is applied. Planning on the MAR dataset is recommended since it improves image quality and CT number accuracy. It also negates the need to contour the artifacts and override the density which can be time consuming.

关键词： CT Metal Artifact Reduction Dosimetry

RESEARCH AND SIMULATION OF THE INFLUENCE OF THREE-AXIAL COMPACTION ON POwDER METALLURGIC PRODUCT PROPERTIES

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Acta Metallurgica Sinica(English Letters) 2008年第2期21卷 116-124页

作者： D. G. wang Y.C. wu M.H. Jiao T.Xie J.w. Yu K G. Fin School of Material and Engineering Hefei University of Technology Hefei 230009 China Institute of Tribology Hefei University of Technology Hefei 230009 China

The warm powder compaction process is simulated by the finite element analysis software, MSCJMARC. The thermal mechanically coupled analysis method is applied on the basis of the updated Lagrangian Method, to simulate the warm powder compaction process. The warm powder compaction process is simulated, and the influence of friction condition and pressing styles are researched on the density of powder green and the mechanics behavior at certain temperature. The results indicate that for cylindrical compacts, with the improvement of the friction condition, the uniformity of distribution of green relative density is largely improved, the pressing force and stress decrease, and the nonconforming pressing processes influence the distribution of green density to some degree. The status of stress distribution of the process that punches firstly press and die finally press is different from the other three processes, and presents the figure of ＇flume ＇.

关键词： Density FEM Property Three-axial compaction

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无情之战太平洋战争中的种族与强权 1版

PRESSURE DISTRIBUTION UNDER NORMAL FEET DURING STANDING AND LEVEL wALKING

2019年

作者：（美）约翰·w.道尔（John w. Dower）

本书从一个崭新的角度剖析并展现出了“二战”中日本和美国间的那一场“无情之战”。在二次世界大战时期的美国人看来，太平洋彼岸的岛国日本生活着一群“小男人”。这些人时而恭顺，时而好战，是原始人、幼童和疯子的综合体。相反，在... 详细信息

ISBN: (数字)9787508685861

ISBN: (纸本)9787508685861

本书从一个崭新的角度剖析并展现出了“二战”中日本和美国间的那一场“无情之战”。在二次世界大战时期的美国人看来，太平洋彼岸的岛国日本生活着一群“小男人”。这些人时而恭顺，时而好战，是原始人、幼童和疯子的综合体。相反，在日本看来美国才是威胁亚洲的魔鬼和野兽。日本作为神选之民，有责任带领亚洲其他国家抗击列强，吊民伐罪。种族主义一旦成为战争工具，其威力堪比任何枪炮，有过之而无不及。在精心设计的宣传策略下，种族偏见助长了暴行，暴行又煽动起更严重的种族仇恨。

关键词：政治、法律政治理论民族、殖民地问题理论

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Medical Bulletin of Shanghai Jiaotong University 1993年第2期16卷 73-79页

作者：汤荣光 w Angus wallace Department of Orthopaedic Surgery The Ninth People's HospitalSSMU Department of Orthopaedic and Accident Surgery University of NottinghamUniversity HospitalQueen's Medical CentreEngland

Foot pressure measurements were performed during standing and level walkingon a series of 30 normal subjects (15 males, 15 females, a total of 60 feet) with amean age of 37.6 yrs and a mean body weight of 66.3 kg. A significant difference wasfound in the peak pressure under the second metatarsal head between males and femaleswith females showing higher pressures than males daring walking (Pwalding were obtained. The rise time to peak pressure at each selected areafor walking was recorded and analysed. The practical application and clinical significanceof these data were also discussed.

关键词： foot pressure force plate peak pressure metatarsal head

In situ calcite U-Pb geochronology by high-sensitivity single-collector LA-SF-ICP-MS

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Science China Earth Sciences 2022年第6期65卷 1146-1160页

作者： Shitou wU Yueheng YANG Nick M.w.ROBERTS Ming YANG Hao wANG Zhongwu LAN Bohang XIE Tianyi LI Lei XU Chao HUANG Liewen XIE Jinhui YANG Fuyuan wU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Geochronology and Tracers Facility British Geological SurveyEnvironmental Science CentreNottinghamNG125GGUK Key Laboratory of Deep Geology and Resources SinopecBeijing 102206China

U-Pb geochronology of calcite using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is an emerging method,with potential applications to a vast array of geological *** to the low levels of U and Pb in calcite,measurement using higher-sensitivity instruments,such as sector field (SF) ICP-MS,have advantages over more commonly used quadrupole (Q) ICP-MS *** a Thermo Element XR ICP-MS,we demonstrate that the Jet+X cone combination with the N_(2) enhancement technique provides the best sensitivity for measuring U and Pb *** higher sensitivity improves the precision of calcite U-Pb isotope measurements,and permits dating at high spatial resolutions (w contents of^(238)U (with a low fluence (~2.0 J cm^(–2)),the laser-induced elemental fractionation of^(206)Pb/^(238)U in the NIST SRM 614,ARM-3 and wC-1 reference materials are insignificant (we analysed four commonly-used calcite U-Pb reference materials (wC-1,Duff Brown Tank,JT,and ASH-15).The results match well with published isotope dilution data,demonstrating the reliability of our ***-3,an andesitic glass,is shown to be an appropriate reference material for both^(207)Pb/^(206)Pb calibration and instrument optimization because of its moderate contents of U(~3.75μg g^(–1)) and Pb (~12.7μg g^(–1)).we further demonstrate that the image-guided approach using LA-ICP-MS elemental mapping is an efficient tool in obtaining robust ages.

关键词： Calcite U-Pb geochronology SF-ICP-MS LA-ICP-MS Sensitivity enhancement Jet sample cones

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压缩机气阀设计与力学原理 1

Monolayer MoS_(2)synaptic devices synergistically modulated by Na^(+)ions and sulfur vacancies for neuromorphic computing and pain perception stimulation

1986年

作者：（美）w.索德尔

本书系统而通俗地介绍了作者对气阀设计的一些观点和方法，包括气阀设计的基本步骤、计算、实验、气阀可靠性、噪声、容积损失、能量损失、计算机模拟和最优化等，也介绍了一些气阀研究的专题成果。

关键词：压缩机设计

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Journal of Materials Science & Technology 2023年第32期163卷 121-131页

作者： Y.B.Liu D.Cai T.C.Zhao M.Shen X.Zhou Z.H.Zhang X.w.Meng D.E.Gu State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610066China Laboratory of Controllable Preparation and Application of Nanomaterials Chinese Academy of SciencesBeijing 100190China

Ion based synaptic devices(ISDs)are one of the excellent candidates for neuromorphic ***,most of ISDs utilized additional ion sources to supply ions for adjusting the conductance of the device channel,which might hinder the large-scale integration for fabricating hierarchical artificial neural *** a high-performance monolayer MoS_(2) ISD is demonstrated using Na^(+)ions doped in MoS_(2) lattice as ion *** from the Na^(+)ions and S vacancy defects in the MoS_(2) lattice,the device not only exhibits various synaptic plasticity(long-and short-term plasticity)and typical biological features(pain-perceptual nociceptors and associative learning),but also has a low synaptic event response voltage(100 mV)and a low energy consumption(0.92 pJ)for a synaptic event.A dissociation-adsorptionmigration-binding model is proposed to elaborate the resistance switching mechanism,which is corroborated by density functional theory calculations and *** addition,an artificial neural network(ANN)based on MoS_(2) ISDs is simulated for the recognition of the MNIST handwritten *** deviation of the recognition accuracy is less than 8%compared to the ideal floating-point numeric *** results provide a new strategy for fabricating high-performance ISDs for neuromorphic computing.

关键词： 2D materials Monolayer Molybdenum disulfide Synapses Neuromorphic computing

Phase fragility and mechatronic reliability for Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3) ferroelectric single crystals-A review

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Journal of Advanced Dielectrics 2014年第1期4卷 18-41页

作者： F.Fang w.Yang School of Aerospace Tsinghua UniversityBeijing 100084P.R.China Institute of Applied Mechanics Zhejiang UniversityHangzhou 310058P.R.China

Single crystals of(1x) Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PMN-xPT)near their morphotropic phase boundaries(MPBs)are under extensive investigations for their extraordinary high dielectric and piezoelectric *** of those single crystals facilitated the breakthrough in ultrasonic transducer materials and *** materials are known to be fragile which often leads to various reliability failures in applications involving electric *** a mechanical sense,the failure modes concern the fracture under an intensive electric field,and the fatigue crack propagation under an alternating electric *** an electrical sense,the failure is exhibited by degenerated hysteresis loop by shrinking the remnant polarization and expanding the coercive *** these modes degrade the performance for ferroelectric *** a departure from the tetragonal TÞferroelectric materials,exemplified by BaTiO_(3) and Pb(ZrTi)O_(3),the domain structures of PMN-PT around the MPB are versatile and intricate,depending sensitively on the composition variation,orientation and previous loading *** this review,the attention is mainly focused on three ***,the phase fragility and multiphase coexistence are presented for both[100]-and[101]-oriented PMN-PT single ***,investigations on electric field-induced fatigue crack propagation are described,along with the orientation effect on the crack propagation ***,the inverse effects of the phase transition and fatigue crack growth on the polarization behavior,or the interaction between the mechanical and electrical degradations will be *** review aims for better understanding the underlying mechanism for the ultrahigh performance of the PMN-PT single crystals,to bridge the studies of ferroelectric materials from the mechanical and electrical senses,as well as to evaluate the reliability of PMN-PT single crystals under device applications.

关键词： Fatigue crack growth PMN-PT single crystals reliability ferroelectrics electric fracture electric fatigue.

Natural orifice transesophageal thoracoscopic surgery:A review of the current state

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world Journal of Gastrointestinal Endoscopy 2010年第1期2卷 3-9页

作者： Brian G Turner Denise w Gee Gastrointestinal Unit Massachusetts General Hospital55 Fruit StreetBostonMA 02114United States Department of Surgery Massachusetts General Hospital15 Parkman StreetBostonMA 02114United States

Since the concept of Natural Orifice Translumenal Endoscopic Surgery(NOTES) was introduced,it has continued to gain significantly in popularity and enthusiasm for its potential clinical *** ability to perform conventional laparoscopic and thoracoscopic procedures without the creation of scars and perhaps faster and less painful recovery has prompted a worldwide devotion to further this *** intraabdominal NOTES has rapidly transitioned from animal models to human trials,applying the NOTES concept to perform thoracic procedures has been slower to gain *** goal of this review is to summarize the current state of transesophageal NOTES thoracoscopy by looking at its potential for diagnostic and therapeutic interventions as well as the challenges in transitioning to human trials.

关键词： Natural orifice translumenal endoscopic surgery Transesophageal Thoracoscopy Mediastinoscopy Esophagotomy Natural orifice Endoscopy