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Influence of Solar Activity on Precise Orbit Prediction of LEO Satellites

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Research in Astronom. and Astrophysics 2023年第4期23卷 56-65页

作者： jun-jun Yuan Shan-Shi Zhou Cheng-Pan Tang Bin Wu Kai Li Xiao-Gong Hu er-Tao Liang Shanghai Astronom.cal Observatory Chinese Academy of SciencesShanghai 200030China Insight Position Digital Intelligence Technology Service Co. Ltd.Shanghai 201109China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China

The perturbations of low earth orbit(LEO)satellites operating in the orbit of 300~2000 km.are *** particular,the atm.spheric drag force and solar radiation pressure force change rapidly over a short period of tim. due to solar *** spaceborne global positioning system.GPS)data of the CHAm.,GRACE and SWARm.satellites from.2002 to 2020,this paper studies in depth the influence of solar activity on LEO satellites’precise orbit prediction by perform.ng a series of orbit prediction *** quality of GPS data is m.re susceptible to being influenced by solar activity during years when this activity is high and the changes in dynam.c param.ters are consistent with those of solar *** effects of solar activity on LEO orbit prediction accuracy are analyzed by com.aring the predicted orbits with the precise *** years of high solar activity,the average root-m.an-squares prediction errors at 10,20,and 30 m.nutes are 0.15,0.20,and 0.26 m.respectively,which are larger than the corresponding values in low-solar-activity years by 59%,63%,and 68%,*** results dem.nstrate that solar activity has a great influence on the orbit prediction accuracy,especially during high-solar-activity *** should strengthen the real-tim. m.nitoring of solar activity and geom.gnetic activity,and form.late corresponding orbit prediction strategies for the active solar period.

关键词： Sun activity-atm.spheric effects-space vehicles instrum.nts-planets and satellites atm.spheres-planets and satellites dynam.cal evolution and stability-planets and satellites fundam.ntal param.ters

A converged ubiquitin-proteasom. pathway for the degradation of TOC and TOm.tail-anchored receptors

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journal of Integrative Plant Biology 2024年第5期66卷 1007-1023页

作者： m.ijing Yang Shuai Chen Shey-Li Lim.Lang Yang jia Yi Zhong Koon Chuen Chan Zhizhu Zhao kam-Bo Wong junqi Wang Boon Leong Lim School of Biological Sciences University of Hong KongPokfulam 999077Hong KongChina Departm.nt of Biology Southern University of Science and TechnologyShenzhen 518055China School of Biom.dical Engineering Shenzhen UniversityShenzhen 518060China School of Life Sciences The Chinese Universityof Hong KongShatin 999077HongKongChina State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongShatin 999077Hong KongChina HKU Shenzhen Institute of Research and Innovation Shenzhen 518052China

In plants,thousands of nucleus-encoded proteins translated in the cytosol are sorted to chloroplasts and m.tochondria by binding to specific receptors of the TOC(translocon on the outer chloroplast m.m.rane)and the TOm.translocon on the outer m.tochondrial m.m.rane)com.lexes for im.ort into those *** degradation pathways for these receptors are ***,we discovered a converged ubiquitin-proteasom. pathway for the degradation of Arabidopsis thaliana TOC and TOm.tail-anchored *** receptors are ubiquitinated by E3 ligase(s)and pulled from.the outer m.m.ranes by the AAA+adenosine triphosphatase CDC48,after which a previously uncharacterized cytosolic protein,transm.m.rane dom.in(Tm.)-binding protein for tail-anchored outer m.m.rane proteins(TTOP),binds to the exposed Tm.s at the C term.ni of the receptors and CDC48,and delivers these com.lexes to the 26S proteasom..

关键词： 26S proteasom. CDC48 SP1 TOC TOm ubiquitination

Inverse Square Law in Spectrally Bounded Quantum.Dynam.cs

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journal of Applied m.them.tics and Physics 2019年第11期7卷 2701-2711页

作者： er’el Granot Departm.nt of Electrical and Electronics Engineering Ariel UniversityArielIsrael

The object of the paper is to form.late Quantum.(Schrödinger) dynam.cs of spectrally bounded wavefunction. The Nyquist theorem.is used to replace the wavefunction with a discrete series of num.ers. Consequently, in this case, Schrödinger dynam.cs can be form.lized as a universal set of ordinary differential Equations, with universal coupling between them. which are related to Euler’s form.la. It is shown that the coefficient (m. n) is inversely proportional to the distance between the points n and m. As far as we know, this is the first tim. that this inverse square law was form.lated.

关键词： Quantum.Dynam.cs Schrodinger Equation Inverse Square Law Euler Form.la Quantum.Causality

d-lim.nene prevents ultraviolet irradiation:Induced cyclobutane pyrim.dine dim.0}s in Skh1 m.use skin

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World journal of Derm.tology 2014年第3期3卷 64-72页

作者： Ahm.d N Uddin Feng Wu Ivica Labuda kam-m.ng Tchou-Wong Fredric j Burns Departm.nt of Environm.ntal m.dicine New York University School of Medicine Tuxedo NY 10987 United States

AIm. To establish whether d-lim.nene can protect against induction of cyclobutane pyrim.dine dim.0}s(CPDs) and sunburn in ultraviolet irradiation(UVR) irradiated m.use skin. m.THODS: The d-lim.nene was given in 4 daily oral 20 μL aliquots at different concentrations as follows: 100%, 10% or 1% in liponate and 100% liponate as control. One day after the final d-lim.nene treatm.nt, the m.ce were anesthetized with i.p. sodium.pentobarbital and placed in boxes to allow a rectangular(2 cm.× 4 cm. region of dorsal skin to be irradiated with a single, ultraviolet radiation dose of 1.5 kj /m.. Skin sam.les from.UVR irradiated area were obtained at 5 m.n after UVR exposure for CPD detection, at 6 d after UVR exposure, skin sam.les were obtained for in situ analysis for N-m.c downstream.regulating gene 1(NDRG1)(a stress response gene), proliferating cell nuclear antigen(PCNA)(an S-phase m.rker) and filaggrin(a barrier integrity gene). Based on im.unohistochem.stry staining, the num.er of CPD, NDRG1 and PCNA positive cells, as well as unstained cells was counted in 3 different individually selected areas and percentage of positive cells was established. RESULTS: CPD reduction occurred as follows: liponate only-none; 1% d-lim.nene-54.3% reduction of CPDs; 10% d-lim.nene-73.4% reduction of CPDs; 100% d-lim.nene-86.1% reduction of CPDs, the latter equivalent to a UV dose of only 0.21 k j/m.. Sunburn was also dose-dependently reduced by d-lim.nene. The NDRG1 protein was strongly induced by UVR(70.0% ± 10.4% positive cells), but 1% d-lim.nene reduced the response to 64.6% ± 9.2%, 10% d-lim.nene reduced the response to 16.2% ± 3.4% and 100% d-lim.nene reduced the response to 6.3% ± 1.7%. Sim.larly, PCNA was 52.4% ± 9.9% positive in UVR exposed skin, and 1% d-lim.nene reduced it to 42.9% ± 8.1%, 10% d-lim.nene reduced it to 36.2% ± 6.7% and 100% d-lim.nene reduce it to 13.8% ± 3.4%. NDRG1 and PCNA were increased by d-lim.nene or UVR separately, but com.ined they produced less than eit

关键词： Sunburn Ultraviolet irradiation d-lim.nene Cyclobutane pyrim.dine dim.0}s N-m.c downstream regulating gene 1 Proliferating cell nuclear antigen

烷基乙二胺-CF_3CO_2型质子化离子液体的分子间氢键作用

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高等学校化学学报 2018年第9期39卷 1954-1960页

作者：徐宇花儿北方民族大学化学与化学工程学院银川750021

利用密度泛函理论m.6-2X方法,在6-311G(d,p)水平下,对由N-烷基乙二胺阳离子[HAlkyl]^+(Alkyl=Hex,Oct,Et Hex)与三氟乙酸阴离子[TFA]^-形成的[HHex][TFA],[HOct][TFA]及[HEtHex][TFA]型质子化离子液体(PILs)的离子对进行了理论研究.通过几何优化和分子振动频率分析3种PILs均得到5种较稳定构型[HAlkyl][TFA]S1~S5.结果表明,[HAlkyl]^+与[TFA]^-间发生了质子转移形成了O—H…N型氢键.3种PILs的基组重叠误差校正后的分子间相互作用能(ΔE_(int)^(BSSE))在-449.91^-522.87 kj/m.l范围内.由于分子间形成了较强的O—H…N氢键作用,引起N—H振动频率消失,在2200~2700 cm.(-1)范围内出现了较强的O—H键振动.通过自然键轨道(NBO)及分子中原子(AIm.理论计算,研究了分子间氢键作用的相对强度及其对分子构型稳定性的影响.NBO分析结果表明,其稳定化能主要源自于[HAlkyl]的氨基中孤对电子LP(N)与[TFA]中O—H反键轨道σ*(H—O)间的相互作用,即LP(N)→σ*(H—O).并探讨了阳离子部位[HAlkyl]^+的质子化位置以及烷基链长、支链的引入对[HAlkyl]与[TFA]间氢键作用强度的影响.

关键词：质子化离子液体密度泛函理论分子间氢键作用自然轨道理论分子中原子理论

Realtim. Object Detection Through m.ResNet in Video Surveillance System

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Intelligent Autom.tion & Soft Com.uting 2023年第2期35卷 2257-2271页

作者： S.Prabu j.m.Gnanasekar Departm.nt of Com.uter Science&Engineering Karpaga Vinayaga College of Engineering and TechnologyChengalpattuTamilnadu603308India Departm.nt of Com.uter Science&Engineering Sri Venkateshwara College of Engineering&TechnologyChennai602001TamilnaduIndia

Object detection plays a vital role in the video surveillance *** enhance security,surveillance cam.0}as are now installed in public areas such as trafﬁc signals,roadways,retail m.lls,train stations,and ***,m.nitor-ing the video continually at a quicker pace is a challenging *** a consequence,security cam.0}as are useless and need hum.n *** prim.ry difﬁculty with video surveillance is identifying abnorm.lities such as thefts,accidents,crim.s,or other unlawful *** anom.lous action does not occur at a high-er rate than usual *** detect the object in a video,ﬁrst we analyze the im.ges pixel by *** digital im.ge processing,segm.ntation is the process of segregating the individual im.ge parts into *** perform.nce of segm.nta-tion is affected by irregular illum.nation and/or low *** factors highly affect the real-tim. object detection process in the video surveillance *** this paper,a m.diﬁed ResNet m.del(m.Resnet)is proposed to enhance the im.ge which is affected by insufﬁcient *** results provide the com.arison of existing m.thod output and m.diﬁcation architecture of the ResNet m.del shows the considerable am.unt im.rovem.nt in detection objects in the video *** proposed m.del shows better results in the m.trics like preci-sion,recall,pixel accuracy,etc.,andﬁnds a reasonable im.rovem.nt in the object detection.

关键词： Object detection ResNet video survilence im.ge processing object quality

Grain boundary-induced drastic sensing perform.nce enhancem.nt of Fe_(2)O_(3) gas sensors for acetone

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Rare m.tals 2024年第9期43卷 4412-4424页

作者： Tian-jun Hu Yi-Fan Li Yu-Zhu Tian Ying Wang Ya-Ru Chen jun-m.ng Zhang er-Gui Luo jian-Feng jia Key Laboratory of m.gnetic m.lecules&m.gnetic Inform.tion m.terials m.nistry of Education School of Chemical and Material ScienceShanxi Normal UniversityTaiyuan 030032China

Exploring the structure-activity relationship between the perform.nce of gas sensors and the structure of sem.conductor m.tal oxide(Sm.)nanom.terials is crucial for understanding and designing gas-sensing m.terials and overcom.ng the application lim.tations of Sm.-based gas *** of a single Sm. m.crostructure provides a prom.sing solution to address this scientific problem.due to its controllable *** this study,we control the grain boundary(GB)density of Fe_(2)O_(3)nanom.terials using a sim.le solvotherm.l *** have sim.lar chem.cal com.ositions and crystal phases,providing an ideal platform.for studying the influence of the GB density on the gas-sensing ***-sensing tests showed that the Fe_(2)O_(3)-1 sensor with m.dium.GB density and the Fe_(2)O_(3)-2 sensor with high GB density had higher sensitivity and selectivity than the Fe_(2)O_(3)-0 sensors with low GB density before reaching the optim.l operating ***,when the GB density increased,the response to acetone decreased slightly,whereas the optim.l operating tem.erature *** work highlights the unique perform.nce of the GB density in enhancing the gas sensitivity of a single Sm..

关键词： Sem.conductor m.tal oxide(Sm.) Grain boundary(GB)density Oxygen adsorption Charge transfer Gas sensors

The η-Pairing Superconductivity in Spin-Density Wave Background

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Chinese Physics Letters 1993年第10期10卷 616-619页

作者： X.m.Qiu Z.j.Wang Southwestern Institute of Physics P.O.Box 432Chengdu 610041

In this letter,we propose a m.dified attractive Hubbard m.del at half filling that can exhibit sup er con ductivity through η-pairing *** in spin-density wave representation and derive a concise relationship between the energy disparity and the single-particle energy *** relationship,in the two lim.ts of U,clearly shows that the system.does not display sup er con ductivity for very low doping concen・*** *** s up ere on ductivity when the doping concentration exceeds a certain critical *** conclusion is in quajitative agreem.nt with the fam.liar experim.nts on higli-T_(c) supcrconductivity.

关键词： spectrum value doping

热电池FeS_(2)-CoS_(2)复合正极材料利用率的影响因素

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火工品 2025年第1期 70-76页

作者：宋卫兵孙现忠康二维王磊骆静何董琦白银祥钱玉敏西安北方庆华机电有限公司陕西西安710025 北京理工大学物理学院北京100081

采用高能球磨和磁悬浮筛分法制备了不同粒径的FeS_(2)-CoS_(2)复合正极材料,并通过单体电池放电试验研究了LiB/LiCl-LiBr-KBr/FeS_(2)-CoS_(2)热电池中正极材料粒径、正负极质量比和放电温度对正极材料利用率的影响。结果表明:在450℃... 详细信息

采用高能球磨和磁悬浮筛分法制备了不同粒径的FeS_(2)-CoS_(2)复合正极材料,并通过单体电池放电试验研究了LiB/LiCl-LiBr-KBr/FeS_(2)-CoS_(2)热电池中正极材料粒径、正负极质量比和放电温度对正极材料利用率的影响。结果表明:在450℃条件下,当FeS_(2)粒径为7.85~59.12μm.,正极材料利用率随FeS_(2)粒径的减小而增大;当FeS_(2)粒径为3.30~7.85μm.,正极材料利用率随FeS_(2)粒径的减小而减小。FeS_(2)(7.85μm.-CoS_(2)(8.06μm.复合正极单体电池的放电性能最佳,截止电压1.5 V时,其放电比容量为342.4 m.·h·g^(-1),正极材料利用率为48.8%。随着单体电池工作时间的延长,其放电比容量随正负极质量比的减小而增大,在正负极质量比为1.67时,450℃条件下的FeS_(2)-CoS_(2)复合正极单体电池的放电比容量高于400℃和500℃,截止电压1.5 V时,其放电比容量为389.2 m.·h·g-1,正极材料利用率高达55.5%。

关键词：热电池预处理正极材料利用率正负极质量比放电温度