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CHARACTERISTICS OF LIP-MOUTH REGION IN SMILING POSITION FROM 80 PERSONS WITH ACCEPTABLE FACES AND INDIVIDUAL NORMAL OCCLUSIONS
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作者 张江恒 陈扬熙 周秀坤 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第3期189-192,共4页
OBJECTIVE: The characteristics of lip-mouth region including the soft and hard tissues in smiling position with frontal fixed position photographic computer-aided analysis were studied. METHODS: The subjects were 80 p... OBJECTIVE: The characteristics of lip-mouth region including the soft and hard tissues in smiling position with frontal fixed position photographic computer-aided analysis were studied. METHODS: The subjects were 80 persons (40 male and 40 females, age range: 17 to approximately 25 years) with acceptable faces and individual normal occlusions. The subjects were asked to take maximum smiling position to accept photographic measurement with computer-aided analysis. RESULTS: The maximum smile line could be divided into 3 categories: low smile line (16.25%), average smile line (68.75%), and high smile line (15%). CONCLUSION: The method adopting maximum smiling position to study the lip-month region is reproducible and comparable. This study would be helpful to provide a quantitative reference for clinical investigation, diagnosis, treatment and efficacy appraisal. 展开更多
关键词 PERSON LIP smilingObjective. The characteristics of lip mouth region including the soft and hard tissues in smiling position with frontal fixed position photographic computer aided analysis were studied. Methods. The subjects were 80 person
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Should China's Manufacturing Industry Transition Towards Both Ends of the "Smiling Curve" ?——A Comparative Analysis between China and Traditional Manufacturing Powers
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作者 王茜 程都 《China Economist》 2014年第1期22-31,共10页
The manufacturing sector in China has surpassed that of the United States in terms of scale.Yet it still suffers from the shocks of an international economic downturn,the lack of core technologies,and the impact of &q... The manufacturing sector in China has surpassed that of the United States in terms of scale.Yet it still suffers from the shocks of an international economic downturn,the lack of core technologies,and the impact of "re-industrialization" of the developed economies.Based on an evaluation of the "smiling curve" theory and selected trade data from 1991 to 2011,this paper performs a comparative analysis of the differences between the manufacturing sectors of China and those of the traditional manufacturing powers in terms of product categories and architecture.This analysis is conducted in order to explore the question of whether China should transition from being the "world's manufacturing plant" to both ends of the "smiling curve".The paper then introduces Japan's "inverted smiling curve " to explore whether profit margins remain in the manufacturing sector.Research shows that China's manufacturing capacity,especially its "integrated" product assembly capacity,has not been fully realized,and that the development of the manufacturing sector can still yield high market returns.As a result,it is necessary for China to continue the path of being the "world's manufacturing plant". 展开更多
关键词 smiling curve manufacturing industry modular type integration
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SMILE治疗近视患者效果及对角膜生物力学的影响
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作者 韩宝军 史芳荣 华剑楠 《国际眼科杂志》 CAS 2024年第4期522-527,共6页
目的:探讨飞秒激光小切口角膜基质透镜取出术(SMILE)治疗近视患者的效果及对角膜生物力学的影响。方法:回顾性研究。选择2020-01/2021-12在安阳市眼科医院拟行角膜屈光手术的近视患者120例240眼。根据手术治疗方式分为SMILE组64例128眼... 目的:探讨飞秒激光小切口角膜基质透镜取出术(SMILE)治疗近视患者的效果及对角膜生物力学的影响。方法:回顾性研究。选择2020-01/2021-12在安阳市眼科医院拟行角膜屈光手术的近视患者120例240眼。根据手术治疗方式分为SMILE组64例128眼,经上皮准分子激光角膜切削术(TransPRK)组56例112眼。比较两组患者术后1、7 d,1、3、6 mo,1 a的裸眼视力、角膜生物力学、角膜内皮细胞数目、角膜后表面高度、角膜表面规则指数、手术并发症。结果:SMILE组患者术后1、7 d,1 mo裸眼视力均优于TransPRK组(均P<0.001),但两组术后3、6 mo,1 a均无差异(均P>0.05)。与术前相比,两组患者术后的角膜补偿眼压、模拟Goldmann眼压、角膜阻力因子、角膜滞后量呈先下降后升高趋势。SMILE组术后1、7 d,1 mo角膜补偿眼压、模拟Goldmann眼压、角膜阻力因子、角膜滞后量均高于TransPRK组(均P<0.05),但术后3、6 mo,1 a均无差异(均P>0.05)。手术前后两组患者角膜内皮细胞数目、角膜后表面高度均无差异(均P>0.05)。与术前相比,两组患者术后角膜表面规则指数呈先升高后降低趋势,但组间比较无差异(P>0.05)。两组患者术后并发症发生率比较无差异(P>0.05)。结论:相比TransPRK,SMILE对角膜生物力学的影响较小,早期视力恢复效果更好,两种手术的远期视力无差异,均有良好的安全性和有效性。 展开更多
关键词 飞秒激光小切口角膜基质透镜取出术(SMILE) 经上皮准分子激光角膜切削术 角膜生物力学 视力
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SMILE,FS-LASIK治疗术对高度近视患者角膜稳定性及视觉质量的影响
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作者 杨晶 刘阳 《中文科技期刊数据库(引文版)医药卫生》 2024年第5期0098-0101,共4页
评估SMILE和FS-LASIK两种手术方式对高度近视患者角膜稳定性及视觉质量的影响。方法 采用回顾性分析选取我院于2020年6月-2021年6月期间收诊的96例高度近视患者,根据治疗方式分为SMILE组与FS-LASIK组,各48例。比较这两种方法对患者角膜... 评估SMILE和FS-LASIK两种手术方式对高度近视患者角膜稳定性及视觉质量的影响。方法 采用回顾性分析选取我院于2020年6月-2021年6月期间收诊的96例高度近视患者,根据治疗方式分为SMILE组与FS-LASIK组,各48例。比较这两种方法对患者角膜稳定性和视觉质量的影响。结果 术后1、3mo的跟踪观察中,与术前相比,两组患者的角膜最薄点显著降低(p<0.05);而角膜后表面高度降低幅度无显著差异(p>0.05)。在术后1mo,SMILE组的角膜最薄点高度高于FS-LASIK组(p<0.05);术后3mo,SMILE组的该高度低于FS-LASIK组,差异不显著(p>0.05)。在术后1、3mo,SMILE组的角膜后表面高度普遍低于FS-LASIK组,无统计学意义(p>0.05)。术后1mo,两组患者客观散射指数(OSI)与术前比较升高,且SMILE组低于FS-LASIK组(p<0.05);术后3mo,两组患者OSI与术前比较升高,且SMILE组低于FS-LASIK组,无统计学差异(p>0.05)。术后1mo,两组患者的调制传递函数截止频率(MTF cut-off)较术前降低,且SMILE组高于FS-LASIK组(p<0.05);术后3mo,两组患者的MTF cut-off值较术前降低,SMILE组高于FS-LASIK组,无统计学差异(p>0.05)。SMILE组的斯特列比(SR)在术后1、3mo均高于FS-LASIK组,但无统计学差异(p>0.05)。结论 SMILE手术在术后早期对高度近视患者的视觉质量改善方面显示出一定的优势,特别是在OSI和MTF cut-off值方面。但就角膜稳定性而言,SMILE和FS-LASIK手术之间无显著差异。这表明SMILE手术是高度近视患者的一个更佳选择,尤其是在考虑早期视觉质量改善方面。 展开更多
关键词 SMILE FS-LASIK 高度近视 角膜稳定性 视觉质量
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飞秒激光小切口角膜基质透镜取出术治疗中度、高度近视的优势研究
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作者 崔燕 刘红杰 +2 位作者 张珍珍 刘霞 任延军 《新疆医科大学学报》 CAS 2024年第7期961-964,969,共5页
目的 分析飞秒激光小切口角膜基质透镜取出术(SMILE)治疗中度、高度近视的优势。方法 回顾性分析2023年5月至2023年10月在本院行飞秒激光术治疗的100例中度、高度近视患者临床资料,根据术式将患者分为两组,行飞秒激光辅助的原位角膜磨镶... 目的 分析飞秒激光小切口角膜基质透镜取出术(SMILE)治疗中度、高度近视的优势。方法 回顾性分析2023年5月至2023年10月在本院行飞秒激光术治疗的100例中度、高度近视患者临床资料,根据术式将患者分为两组,行飞秒激光辅助的原位角膜磨镶术(FS-LASIK)者为A组(49例98眼),行SMILE者为B组(51例102眼)。分别比较两组中度、高度近视患者不同术式治疗后角膜形态、视觉质量参数、眼压、泪膜破裂时间、Schirmer Ⅰ值、眼部舒适度评分(Kolcaba评分)、眼部视觉模拟评分量表评分(VAS评分)的差异。结果 (1)两组中度、高度近视患者术后3个月,角膜后表面曲率、角膜后表面顶点高度、非球面因子Q值差异无统计学意义(P>0.05)。(2)术后1、7 d,两组Z_(3)^(1)、Z_(3)^(-1)比较差异无统计学意义(P>0.05);但B组角膜前表面高阶像差、Z_(4)^(0)均低于A组(P<0.05)。B组中度、高度近视患者术后角膜前表面高阶像差、Z_(4)^(0)均低于A组(P<0.05);两组术后Z_(3)^(1)、Z_(3)^(-1)比较差异无统计学意义(P>0.05)。(3)两组中度、高度近视患者术后3个月眼压、泪膜破裂时间、Schirmer Ⅰ值差异均无统计学意义(P>0.05)。(4)术后3个月,两组中度、高度近视患者眼压、泪膜破裂时间、Schirmer Ⅰ值、Kolcaba评分、VAS评分差异均无统计学意义(P>0.05)。结论 FS-LASIK、SMILE手术治疗均可实现对中度、高度近视患者屈光矫正效果,治疗后均可获得稳定角膜表面形态,患者主观眼部感受均良好,但SMILE术后短期内视觉质量提升优势显著。 展开更多
关键词 飞秒激光辅助原位角膜磨镶术(FS-LASIK) 飞秒激光小切口角膜基质透镜取出(SMILE) 角膜形态 视觉质量
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Ground-based and additional science support for SMILE 被引量:2
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作者 J.A.Carter M.Dunlop +46 位作者 C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.James L.Juusola K.Kauristie E.A.Kronberg M.Lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang 《Earth and Planetary Physics》 EI CSCD 2024年第1期275-298,共24页
The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplane... The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere ionosphere.Combining these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE mission.Here,we describe current community efforts to prepare for SMILE,and the benefits and context various experiments that have explicitly expressed support for SMILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these efforts.Preparations include constructing an online SMILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft conjunctions.We anticipate growing interest and community engagement with the SMILE mission,and we welcome novel ideas and insights from the solar-terrestrial community. 展开更多
关键词 MAGNETOSPHERE IONOSPHERE magnetosphere-ionosphere coupling ground-based experimentation SMILE CONJUNCTIONS MISSIONS
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SMILE术后主导眼转变及对视觉质量的影响
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作者 张娟 易湘龙 +1 位作者 杨超 张婷 《国际眼科杂志》 CAS 2024年第7期1132-1138,共7页
目的:分析SMILE术后主导眼的转变情况及对视觉质量的影响。方法:前瞻性临床研究。选取2022-06/12在新疆医科大学第一附属医院行SMILE术矫正近视的患者140例280眼,根据术后3 mo内随访时卡洞法检查主导眼别转变情况分为转变组(46例92眼)... 目的:分析SMILE术后主导眼的转变情况及对视觉质量的影响。方法:前瞻性临床研究。选取2022-06/12在新疆医科大学第一附属医院行SMILE术矫正近视的患者140例280眼,根据术后3 mo内随访时卡洞法检查主导眼别转变情况分为转变组(46例92眼)和非转变组(94例188眼)。术前、术后1、3 mo,评估两组患者的裸眼视力(UCVA),采用屈光矫正者生活质量(QIRC)量表评估主观视觉质量,并检测全眼高阶像差评价客观视觉质量。结果:纳入患者SMILE术前主导眼为右眼105例,左眼35例,术后1 mo 46例患者主导眼发生转变,术后3 mo较术后1 mo无新发主导眼转变。术前、术后1、3 mo,转变组和非转变组患者UCVA、QIRC量表评分均无差异(P>0.05)。两组患者主导眼比较,术后3 mo转变组患者总高阶像差、球差显著高于非转变组(P=0.030、0.046);两组患者非主导眼比较,术后1 mo转变组患者三叶草像差显著高于非转变组(P=0.008)。术后1 mo,转变组患者双眼三叶草像差差值明显高于非转变组(P=0.022),余均无差异。结论:SMILE术后部分患者会发生主导眼的转变,但对主观视觉质量无显著影响,术后早期客观视觉质量下降可能是主导眼转变的相关因素。 展开更多
关键词 近视 飞秒激光小切口角膜基质透镜取出术(SMILE) 主导眼 转变 全眼像差 视觉质量
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Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath 被引量:2
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作者 Jin Guo TianRan Sun +6 位作者 San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang 《Earth and Planetary Physics》 EI CSCD 2024年第1期47-58,共12页
Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging ... Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered. 展开更多
关键词 MAGNETOPAUSE X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation
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Tomographic reconstruction of the Earth’s magnetosheath from multiple spacecraft:a theoretical study 被引量:2
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作者 A.M.Jorgensen TianRan Sun +4 位作者 Y.Huang L.Li R.Xu L.Dai Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期204-214,共11页
Following our earlier work on tomographic reconstruction of the magnetosheath soft X-ray emissions with superposed epoch analysis of many images recorded from a single spacecraft we now explore the instantaneous recon... Following our earlier work on tomographic reconstruction of the magnetosheath soft X-ray emissions with superposed epoch analysis of many images recorded from a single spacecraft we now explore the instantaneous reconstruction of the magnetosheath and magnetopause using a few images recorded simultaneously from a few spacecraft.This work is motivated by the prospect of possibly having two or three soft X-ray imagers in space in the coming years,and that many phenomena which occur at the magnetopause boundary,such as reconnection events and pressure pulse responses,do not lend themselves as well to superposed epoch analysis.If the reconstruction is successful-which we demonstrate in this paper that it can be-this collection of imagers can be used to reconstruct the magnetosheath and magnetopause from a single image from each spacecraft,allowing for high time resolution reconstructions.In this paper we explore the reconstruction using,two,three,and four spacecraft.We show that the location of the subsolar point of the magnetopause can be determined with just two satellites,and that volume emissions of soft X-rays,and the shape of the boundary,can be reconstructed using three or more satellites. 展开更多
关键词 MAGNETOSHEATH TOMOGRAPHY soft X-ray imaging SMILE
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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries 被引量:2
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作者 M.Grandin H.K.Connor +5 位作者 S.Hoilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth 《Earth and Planetary Physics》 EI CSCD 2024年第1期70-88,共19页
Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing tech... Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can result in an enhancement in the soft X-ray signal by 4%.These are likely conservative estimates,given that the solar wind conditions used in the Vlasiator run can be expected to generate weaker soft X-ray emissions than the more common denser solar wind.These results will contribute to the preparatory work for the SMILE and LEXI missions by providing the community with quantitative estimates of the effects of small-scale,transient phenomena occurring on the dayside. 展开更多
关键词 MAGNETOSPHERE MAGNETOSHEATH numerical simulation SMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves
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Deformations at Earth’s dayside magnetopause during quasi-radial IMF conditions:Global kinetic simulations and Soft X-ray Imaging 被引量:2
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作者 ZhongWei Yang RiKu Jarvinen +7 位作者 XiaoCheng Guo TianRan Sun Dimitra Koutroumpa George K.Parks Can Huang BinBin Tang QuanMing Lu Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期59-69,共11页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)is a joint mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS).Primary goals are investigating the dynamic response of the Eart... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)is a joint mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS).Primary goals are investigating the dynamic response of the Earth's magnetosphere to the solar wind(SW)impact via simultaneous in situ magnetosheath plasma and magnetic field measurements,X-Ray images of the magnetosheath and magnetic cusps,and UV images of global auroral distributions.Magnetopause deformations associated with magnetosheath high speed jets(HSJs)under a quasi-parallel interplanetary magnetic field condition are studied using a threedimensional(3-D)global hybrid simulation.Soft X-ray intensity calculated based on both physical quantities of solar wind proton and oxygen ions is compared.We obtain key findings concerning deformations at the magnetopause:(1)Magnetopause deformations are highly coherent with the magnetosheath HSJs generated at the quasi-parallel region of the bow shock,(2)X-ray intensities estimated using solar wind h+and self-consistentO7+ions are consistent with each other,(3)Visual spacecraft are employed to check the discrimination ability for capturing magnetopause deformations on Lunar and polar orbits,respectively.The SMILE spacecraft on the polar orbit could be expected to provide opportunities for capturing the global geometry of the magnetopause in the equatorial plane.A striking point is that SMILE has the potential to capture small-scale magnetopause deformations and magnetosheath transients,such as HSJs,at medium altitudes on its orbit.Simulation results also demonstrate that a lunar based imager(e.g.,Lunar Environment heliospheric X-ray Imager,LEXI)is expected to observe a localized brightening of the magnetosheath during HSJ events in the meridian plane.These preliminary results might contribute to the pre-studies for the SMILE and LEXI missions by providing qualitative and quantitative soft X-ray estimates of dayside kinetic processes. 展开更多
关键词 collisionless shock SMILE mission FORESHOCK
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On the apparent line-of-sight alignment of the peak X-ray intensity of the magnetosheath and the tangent to the magnetopause,as viewed by SMILE-SXI 被引量:2
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作者 Andrew Read 《Earth and Planetary Physics》 EI CSCD 2024年第1期155-172,共18页
The Soft X-ray Imager(SXI)on board the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)spacecraft will be able to view the Earth’s magnetosheath in soft X-rays.Simulated images of the X-ray emission visible f... The Soft X-ray Imager(SXI)on board the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)spacecraft will be able to view the Earth’s magnetosheath in soft X-rays.Simulated images of the X-ray emission visible from the position of SMILE are created for a range of solar wind densities by using 3 years of the SMILE mission orbit,together with models of the expected X-ray emissivity from the Earth’s magnetosheath.Results from global magnetohydrodynamic simulations and a simple model for exospheric neutral densities are used to compare the locations of the lines of sight along which integrated soft X-ray intensities peak with the lines of sight lying tangent to surfaces(defined here to be the magnetopause)along which local soft X-ray intensities peak or exhibit their strongest gradients,or both,for strongly southward interplanetary magnetic field conditions when no depletion or low-latitude boundary layers are expected.Where,in the parameter space of the various times and seasons,orbital phases,solar wind conditions,and magnetopause models,the alignment of the X-ray emission peak with the magnetopause tangent is good,or is not,is presented.The main results are as follows.The spacecraft needs to be positioned well outside the magnetopause;low-altitude times near perigee are not good.In addition,there are seasonal aspects:dayside-apogee orbits are generally very good because the spacecraft travels out sunward at high altitude,but nightside-apogee orbits,behind the Earth,are bad because the spacecraft only rarely leaves the magnetopause.Dusk-apogee and dawnapogee orbits are intermediate.Dayside-apogee orbits worsen slightly over the first three mission years,whereas nightside-apogee orbits improve slightly.Additionally,many more times of good agreement with the peak-to-tangent hypothesis occur when the solar wind is in a high-density state,as opposed to a low-density state.In a high-density state,the magnetopause is compressed,and the spacecraft is more often a good distance outside the magnetopause. 展开更多
关键词 X-rays MAGNETOSPHERE MAGNETOSHEATH MAGNETOPAUSE Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) Earth solar wind charge exchange
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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause 被引量:2
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作者 RongCong Wang JiaQi Wang +3 位作者 DaLin Li TianRan Sun XiaoDong Peng YiHong Guo 《Earth and Planetary Physics》 EI CSCD 2024年第1期133-154,共22页
Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosph... Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray imaging.However,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the magnetopause.The analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration models.This makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical models.We propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the magnetosphere.The idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch estimator.The Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the estimator.Experimental results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural similarity.The restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving the reconstruction results.Hence,the proposed technology may be feasible for processing SXI-simulated observation images. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager MAGNETOPAUSE image restoration
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半导体激光Bar条应力抑制研究
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作者 魏传祥 宋英民 +2 位作者 李昊翰 王勇 王宪涛 《长春理工大学学报(自然科学版)》 2024年第4期18-24,共7页
为抑制半导体激光器件封装应力和Y、Z轴方向的形变,提出了一种用于封装高功率半导体激光Bar条,且具有通过丝杠实现应力调节机制的双热沉封装结构。利用有限元法分析了半导体激光器CS和应力可调节双热沉两种封装结构的应力分布,以及在CW... 为抑制半导体激光器件封装应力和Y、Z轴方向的形变,提出了一种用于封装高功率半导体激光Bar条,且具有通过丝杠实现应力调节机制的双热沉封装结构。利用有限元法分析了半导体激光器CS和应力可调节双热沉两种封装结构的应力分布,以及在CW连续工作条件下两种封装在Y、Z轴方向的形变,并对不同调节应力Bar条的应力分布进行了仿真分析。分析表明,应力可调节式双热沉封装结构有效减小了工作热应力并抑制了Smile效应和热透镜效应,为半导体激光Bar条的应力抑制研究提供一定的理论支撑与参考。 展开更多
关键词 半导体激光器 Smile效应 热透镜效应 热沉 封装应力 有限元分析
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Preface to the Special Issue on Modeling and Data Analysis Methods for the SMILE mission 被引量:1
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作者 TianRan Sun Hyunju Connor Andrey Samsonov 《Earth and Planetary Physics》 EI CSCD 2024年第1期1-4,共4页
The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)project(http://www.nssc.cas.cn/smile/,https://www.cosmos.esa.int/web/smile/mission)is a joint spacecraft mission of the European Space Agency(ESA)and the Chi... The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)project(http://www.nssc.cas.cn/smile/,https://www.cosmos.esa.int/web/smile/mission)is a joint spacecraft mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)with an expected launch in 2025.SMILE aims to study the global interactions of solar wind–magnetosphere–ionosphere innovatively by imaging the Earth’s magnetosheath and cusps in soft X-rays and the northern auroral region in ultraviolet(UV)while simultaneously measuring plasma and magnetic field parameters in the solar wind and magnetosheath along a highly-elliptical and highly-inclined orbit.This special issue is composed of 22 articles,presenting recent progress in modeling and data analysis techniques developed for the SMILE mission.In this preface,we categorize the articles into the following seven topics and provide brief summaries:(1)instrument descriptions of the Soft X-ray Imager(SXI),(2)numerical modeling of the X-ray signals,(3)data processing of the X-ray images,(4)boundary tracing methods from the simulated images,(5)physical phenomena and a mission concept related to the scientific goals of SMILE-SXI,(6)studies of the aurora,and(7)ground-based support for SMILE. 展开更多
关键词 SMILE X-ray imaging MAGNETOSPHERE auroral IONOSPHERE
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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter 被引量:1
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作者 Hyangpyo Kim Hyunju K.Connor +9 位作者 Jaewoong Jung Brian M.Walsh David Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier 《Earth and Planetary Physics》 EI CSCD 2024年第1期173-183,共11页
The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective l... The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind conditions.To suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray images.In this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is maximized.Two assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause curvature.We create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson noise.We then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea ks.From the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground truth.Our method estimates RS with an accuracy of<0.3 RE when the solar wind density exceeds>10 cm-3.The accuracy improves for greater solar wind densities and during southward interplanetary magnetic fields.The method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field turnings.Consequently,the technique will enable quantitative analysis of the magnetopause motion and help reveal the dayside reconnection modes for dynamic solar wind conditions.This technique will suppo rt the LEXI and SMILE missions in achieving their scientific o bjectives. 展开更多
关键词 soft X-ray MAGNETOPAUSE RECONNECTION low-pass filter LEXI SMILE
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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation 被引量:1
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作者 S.Parsons D.J.Hall +4 位作者 O.Hetherington T.W.Buggey T.Arnold M.W.J.Hubbard A.Holland 《Earth and Planetary Physics》 EI CSCD 2024年第1期25-38,共14页
Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the sof... Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance level.Three CCDs have been characterised,the two flight devices and the flight spa re.This has been carried out at the Open University in a bespo ke cleanroom measure ment facility.The results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe rature.However at the nominal ope rating tempe rature(-120℃) it is within the procure ment specifications.Overall,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science mode.The se rial charge transfer inefficiency degrades with temperature in full frame mode.However any charge losses are recovered when binning/frame transfer is implemented. 展开更多
关键词 CCD soft X-ray imager characterisation SMILE
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Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar 被引量:2
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作者 JiaoJiao Zhang TianRan Sun +7 位作者 XiZheng Yu DaLin Li Hang Li JiaQi Guo ZongHua Ding Tao Chen Jian Wu Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期299-306,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp regions.It uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic field.The SMILE satellite is scheduled to launch in 2025.The European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar region.It has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry capabilities.Joint detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–ionosphere.Therefore,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint detection.In addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection
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Perception of dental appearance and aesthetic analysis among patients,laypersons and dentists 被引量:1
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作者 Alhanoof Aldegheishem Hadeel Mohammed Alfayadh +5 位作者 Munirah AlDossary Shahad Asaad Elzahraa Eldwakhly Nour AL Huda AL Refaei Dana Alsenan Mai Soliman 《World Journal of Clinical Cases》 SCIE 2024年第23期5354-5365,共12页
BACKGROUND Current concepts of beauty are increasingly subjective,influenced by the viewpoints of others.The aim of the study was to evaluate divergences in the perception of dental appearance and smile esthetics amon... BACKGROUND Current concepts of beauty are increasingly subjective,influenced by the viewpoints of others.The aim of the study was to evaluate divergences in the perception of dental appearance and smile esthetics among patients,laypersons and dental practitioners.The study goals were to evaluate the influence of age,sex,education and dental specialty on the participants’judgment and to identify the values of different esthetic criteria.Patients sample included 50 patients who responded to a dental appearance questionnaire(DAQ).Two frontal photographs were taken,one during a smile and one with retracted lips.Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from(0-10),where 0 represent(absolutely unaesthetic)and 10 represent(absolutely aesthetic).One-way analysis of variance(ANOVA)and t-test analysis were measured for each group.Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance.Among laypersons(including 488 participants),47 pictures“with lips”out of 50 had higher mean aesthetic scores compared to pictures“without lips”.Among the dentist sample,90 dentists’perception towards the esthetic smile and dental appearance for photos“with lips”and“without lips”were the same for 23 out of 50 patients.Perception of smile aesthetics differed between patients,laypersons and dentists.Several factors can contribute to shape the perception of smile aesthetic.AIM To compare the perception of dental aesthetic among patients,laypersons,and professional dentists,to evaluate the impact of age,sex,educational background,and income on the judgments made by laypersons,to assess the variations in experience,specialty,age,and sex on professional dentists’judgment,and to evaluate the role of lips,skin shade and tooth shade in different participants’judgments.METHODS Patients sample included 50 patients who responded to DAQ.Two frontal photographs were taken:one during a smile and one with retracted lips.Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from(0-10),where 0 represent(absolutely unaesthetic)and 10 represent(absolutely aesthetic).One-way ANOVA and t-test analysis were measured for each group.RESULTS Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance.Among laypersons(including 488 participants),47 pictures“with lips”out of 50 had higher mean aesthetic scores compared to pictures“without lips”.Whereas among the dentist sample,90 dentists’perception towards the esthetic smile and dental appearance for photos“with lips”and“without lips”were the same for 23 out of 50 patients.Perception of smile aesthetics differed between patients,laypersons and dentists.CONCLUSION Several factors can contribute to shape the perception of smile aesthetic. 展开更多
关键词 Aesthetic perception Laypersons Dental appearance DENTISTS Smile analysis Dental aesthetic
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SMILE不同角膜帽厚度对近视散光患者术后散光及早期视觉质量的影响
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作者 张新立 刘洋 +1 位作者 符建 刘向玲 《国际眼科杂志》 CAS 2024年第11期1811-1815,共5页
目的:比较飞秒激光小切口角膜基质透镜取出术(SMILE)中不同眼角膜帽厚度对近视散光患者术后散光及早期视觉质量的影响。方法:采用前瞻性对照研究,选取我院2020-06/2022-06接受SMILE手术的近视散光患者54例108眼,根据随机数字表法分为A组... 目的:比较飞秒激光小切口角膜基质透镜取出术(SMILE)中不同眼角膜帽厚度对近视散光患者术后散光及早期视觉质量的影响。方法:采用前瞻性对照研究,选取我院2020-06/2022-06接受SMILE手术的近视散光患者54例108眼,根据随机数字表法分为A组、B组(各27例54眼),A组、B组角膜帽厚度设计分别为110、120μm,其余手术参数一致。比较两组患者术前及术后1 d,1 wk,1 mo的裸眼视力(UCVA)、等效球镜度(SE)、角膜硬度参数(SP-A1)、视觉质量和散光矢量分析结果等。结果:两组患者手术前后各时间点的UCVA、SE、SP-A1有时间差异(均P<0.05),术后1 d A组UCVA优于B组(P<0.05)。两组患者的散光矢量分析结果比较无差异(均P>0.05)。术后1 d A组的客观散射指数(OSI)低于B组,斯特列尔比(SR)高于B组(均P<0.05)。两组间术后调制传递函数截止频率(MTF cut off)、对比度视力、视觉症状及总体满意度、并发症发生率比较无差异(均P>0.05)。结论:110μm或120μm的角膜帽厚度在SMILE矫正近视散光方面均是安全有效的,且不影响术后的SE、散光、SP-A1以及对比度视力。110μm角膜帽厚度术后早期视力恢复更快且早期视觉质量优于120μm。 展开更多
关键词 飞秒激光小切口角膜基质透镜取出术(SMILE) 角膜帽厚度 近视 散光 视觉质量
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