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用于主动式导弹的回路中含有硬件的仿真

航空兵器 1983年第4期 28-38页

作者： mitchell e.sisle edward D.McCarthy 吴永刚雷锡恩公司系统仿真部雷锡恩公司目标仿真组经理经理

文提出了回路中含有硬件的仿真(hardware-in-the-loop simulation)方法,用于评价主动式导弹从发射前到截获目标的整个过程的性能。这套设备可用来进行系统的综合、设计验证、飞行前及飞行后的分析以及系统性能的复现。一台 CDC 公司的 C... 详细信息

文提出了回路中含有硬件的仿真(hardware-in-the-loop simulation)方法,用于评价主动式导弹从发射前到截获目标的整个过程的性能。这套设备可用来进行系统的综合、设计验证、飞行前及飞行后的分析以及系统性能的复现。一台 CDC 公司的 Cyberl75通用计标机和 ADI 公司生产的一台多处理机系统联用,实现实时的六自由度仿真。这种仿真包括了目标模型、导弹模型以及它们的相对运动。Cyber175述通过一台 HP1000计算机驱动射频环境模型。射频环境模型给出必要的幅相控制,用以复现一个十点闪烁模型。这套设备还能接收主动辐射,给出距离、角度和速度各不相同的四个独立的回波信号。这套设备虽然尚未通过正式的鉴定程序,但模拟结果已与主动导弹的纯数字仿真进行了比较。和飞行试验结果的初步比较也说明了这套设备的可信度。

关键词：导弹目标发生器目标模型微波暗室无电波反射室实验室主动式硬件回路

Scavenging and release of Ree and HFSe by Na-metasomatism in magmatic-hydrothermal systems

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Fundamental Research 2024年第2期4卷 315-323页

作者： Wu-Bin Yang He-Cai Niu Ning-Bo Li Pete Hollings Shannon Zurevinski Roger H.mitchell Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for excellence in Deep earth Science Guangzhou 510640China Department of Geology Lakehead UniversityThunder BayON P7B 5E1Canada

exploitable or potentially exploitable deposits of critical metals,such as rare-earth(Ree)and high-field-strength elements(HFSe),are commonly associated with alkaline or peralkaline igneous ***,the origin,transport and concentration of these metals in peralkaline systems remains poorly *** study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in Ne China,to assess the remobilization and redistribution of Ree and HFSe during magmatic-hydrothermal *** amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions,with increasing Ree and HFSe concentrations as a function of increasing Na-index[Na^(#),defined as molar Na/(Na+Ca)ratios].The Na-amphiboles(i.e.,arfvedsonite)and aegirine-augites can be subsequently altered,or breakdown,to form hydrothermal aegirine during late-or post-magmatic *** compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable Ree(2194-3627 ppm)and HFSe(4194-16,862 ppm)contents,suggesting that these critical metals can be scavenged by alkali amphiboles and *** to the primary aegirine-augites,the presentative early replacement aegirine(Aeg-I,Na^(#)=0.91-0.94)has notably lower Ree(1484-1972)and HFSe(4351-5621)*** contrast,the late hydrothermal aegirine(Aeg-II,Na^(#)=0.92-0.96)has significantly lower Ree(317-456 ppm)and HFSe(6.44-72.2 ppm)*** that the increasing Na^(#)from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism,a scavenging-release model can explain the remobilization of Ree and HFSe in peralkaline granitic *** scavenging and release of Ree and HFSe by Na-metasomatism provides key insights into the genesis of globally significant Ree and HFSe *** high Na-index of th

关键词： Critical metals Alkali amphiboles Na-metasomatism Ree and HFSe Na-index(Na^(#))

Des racines et des ailes La culture du droit humain a la subsistance en Chine

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中国与非洲（法文版） 2024年第3期16卷 32-33页

作者： eHIZUeLeN MICHAeL mitchell OMORUYI Centre d'etudes nigerianes Institut d'etudes africainesUniversite normale du Zhejiang

La Chine met en avant les droits a la subsistance et au développement commeétant les plus fondamentaux des droits *** peuple chinois s'est engage avec determination dans la protection des droits de I'homme,un idéal que I'humanite cherche a atteindre depuis de nombreuses *** son influence croissante sur la scene mondiale,la Chine aévolue d'une posture traditionnellement defensive vers un engagement plus actif dans la defense des droits de I'homme a I'eéchelle internationale,notamment au sein du Conseil des droits de I'homme des Nations unies.

关键词： des les culture

Neurosurgical and pharmacological management of dystonia

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World Journal of Psychiatry 2024年第5期14卷 624-634页

作者： Ali Ahmed Mohamed Steven Faragalla Asad Khan Garrett Flynn Gersham Rainone Phillip mitchell Johansen Brandon Lucke-Wold Charles e Schmidt College of Medicine Florida Atlantic UniversityBoca RatonFL 33431United States Department of Neurosurgery and Brain Repair University of South FloridaTampaFL 33606United States Department of Neurosurgery University of FloridaGainesvilleFL 32611United States

Dystonia characterizes a group of neurological movement disorders characterized by abnormal muscle movements,often with repetitive or sustained contraction resulting in abnormal *** types of dystonia present based on the affected body regions and play a prominent role in determining the potential efficacy of a given *** most patients afflicted with these disorders,an exact cause is rarely identified,so treatment mainly focuses on symptomatic *** agents,such as oral anticholinergic administration and botulinum toxin injection,play a major role in the initial treatment of *** more severe and/or refractory cases,focal areas for neurosurgical intervention are identified and targeted to improve quality of *** brain stimulation(DBS)targets these anatomical locations to minimize dystonia *** ablation procedures and peripheral denervation surgeries also offer potential treatment to patients who do not respond to *** management options grant providers and patients the ability to weigh the benefits and risks for each individual patient *** review article explores these pharmacological and neurosurgical management modalities for dystonia,providing a comprehensive assessment of each of their benefits and shortcomings.

关键词： Botulinum toxin Magnetic resonance imaging-guided focused ultrasound Surgical ablation Deep brain stimulation Peripheral denervation surgery Antipsychotics

Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States

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World Journal of Orthopedics 2024年第8期15卷 754-763页

作者： Mahad M Hassan Aliya G Feroe Brenton W Douglass Andrew e Jimenez Benjamin Kuhns Charles F mitchell Robert L Parisien Daniel A Maranho eduardo N Novais Young-Jo Kim Ata M Kiapour Department of Orthopedic Surgery University of MinnesotaMinneapolisMN 55454United States Department of Orthopedic Surgery TRIA Orthopaedic CenterBloomingtonMN 55122United States Department of Orthopedic Surgery Boston Children’s HospitalBostonMA 02115United States Department of Orthopedic Surgery Mayo ClinicRochesterMN 55901United States Department of Orthopaedics and Rehabilitation Yale School of MedicineNew HavenCT 06510United States Department of Orthopedic Surgery American Hip Institute Research FoundationDes PlainesIL 60018United States Department of Orthopedic Surgery Mount SinaiNew YorkNY 10029United States Department of Biomechanics Medicineand Rehabilitation of the Locomotor SystemRibeirao Preto Medical SchoolUniversity of São PauloRibeirao Preto 14048-900São PauloBrazil

BACKGROUND The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular *** To analyze the three-dimensional asphericity of the femoral head of asymptomatic pediatric *** hypothesized that femoral head asphericity will vary significantly between male and female pediatric hips and increase with age in both *** Computed tomography scans were obtained on 158 children and adolescents from a single institution in the United States(8-18 years;50%male)without hip *** femoral measurements including the femoral head diameter,femoral head volume,residual volume,asphericity index,and local diameter difference were used to evaluate femoral head *** In both sexes,the residual volume increased by age(Pespite significantly smaller femoral head size in older ages(>13 years)in females,there were no sex-differences in residual volume and aspherity *** were no age-related changes in mean diameter difference in both sexes(P=0.07)with no significant sex-differences across different age groups(P=0.06).In contrast,there were significant increases in local aspherity(maximum diameter difference)across whole surface of the femoral head and all quadrants except the inferior regions in males(P=0.03).There were no sex-differences in maximum diameter difference at any regions and age group(P>0.05).Increased alpha angle was only correlated to increased mean diameter difference across overall surface of the femoral head(P=0.024).CONCLUSION There is a substantial localized asphericity in asymptomatic hips which increases with age *** 2D measured alpha angle can capture overall asphericity of the femoral head,it may not be sensitive enough to represent regional asphericity patterns.

关键词： Hip Femoral head Sphericity Skeletal growth Sex differences

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

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Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei e Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

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Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： J.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides