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The first photometric investigation of the contact binary OQ Cam

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Research in Astronomy and Astrophysics 2020年第11期20卷 252-258页

作者： Ya-Ni Guo Kai Li qi-qi xia Xing Gao Lin-qiao Jiang Yuan Liu Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China Xinjiang Astronomical Observatory Urumqi 830011China Artificial Intelligence Key Laboratory of Sichuan Province Sichuan University of Science&EngineeringZigong 643000China qilu Institute of Technology Jinan 250200China

The first charge-coupled device photometric light curves in B,V,Rc,and Ic bands of the short-period contact binary star OQ Cam are *** analyzing the light curves with the WilsonDevinney code,it is found that OQ Cam is a W-type shallow contact binary star with a contact degree of f=20.2%.Based on the O-C analyzing,the orbit period displays a long term increasing with a rate of d P/dt=4.40×10^-7 d *** increasing in orbit period can be interpreted by mass transfer from the less massive component to the more massive *** the orbit period increases,OQ Cam would evolve from the present shallow contact configuration to a non-contact *** it may be a potential candidate to confirm the thermal relaxation oscillation theory.

关键词： stars binaries close stars binaries eclipsing stars evolution stars individual(OQ Cam)

Photometric investigations on two totally eclipsing contact binaries:V342 UMa and V509 Cam

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Research in Astronomy and Astrophysics 2019年第10期19卷 75-86页

作者： Kai Li qi-qi xia Jin-Zhong Liu Yu Zhang Xing Gao Shao-Ming Hu Di-Fu Guo Xu Chen Yuan Liu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China qilu Institute of Technology Jinan 250200 China

By analyzing two sets of complete BV Rc Ic light curves for V342 UMa and three sets of complete BV Rc Ic light curves for V509 Cam, we determined that the two systems are both W-subtype contact binaries and that V342 UMa manifests a shallow contact configuration, while V509 Cam exhibits a medium contact configuration. Given that both of them are totally eclipsing binaries, the physical parameters derived only by the photometric light curves are reliable. Meanwhile, the period changes of the two targets were analyzed based on all available eclipsing times. We discovered that V342 UMa shows long-term period decrease with a rate of-1.02(±0.54)× 10^-7 d yr^-1 and that V509 Cam displays long-term period increase with a rate of 3.96(±0.90)× 10^-8 d yr^-1. Both the conservative mass transfer and angular momentum loss via magnetic stellar winds can be used to interpret the long-term period decrease of V342 UMa. The longterm period increase of V509 Cam can be explained by mass transfer from the less massive star to the more massive one. The absolute parameters of the two binaries were estimated according to their Gaia distances and our derived photometric solution results. This method can be extended to other contact binaries without radial velocities but with reliable photometric solutions. Their evolutionary states were investigated and we found that they reveal properties that are identical to other W-subtype contact systems.

关键词： stars binaries close-stars eclipsing-stars individual (V342UMa, V509Cam)

Chondroitinase ABC combined with Schwann cell transplantation enhances restoration of neural connection and functional recovery following acute and chronic spinal cord injury

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Neural Regeneration Research 2025年第5期20卷 1467-1482页

作者： Wenrui Qu xiangbing Wu Wei Wu Ying Wang Yan Sun Lingxiao Deng Melissa Walker Chen Chen Heqiao Dai qi Han Ying Ding Yongzhi xia George Smith Rui Li Nai-Kui Liu xiao-Ming Xu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteDepartment of Neurological SurgeryIndiana University School of MedicineIndianapolisINUSA Department of Hand Surgery the Second Hospital of Jilin UniversityChangchunJilin ProvinceChina Shriners Hospitals Pediatric Research Center Temple University School of MedicinePhiladelphiaPAUSA Department of Anatomy&Cell Biology Indiana University School of MedicineIndianapolisINUSA

Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal *** we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord *** report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal *** Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder ***,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord *** findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.

关键词： axonal regrowth bladder function chondroitinase ABC functional recovery glial scar lentivirus migration Schwann cell spinal cord injury transplantation

A conducted emission mitigation method for software-defined radios through vector signal cancellation

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Chinese Journal of Aeronautics 2023年第9期36卷 289-298页

作者： Siyu xia qi WU School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Recently,Software-Defined Radio(SDR)has gained great popularity owing to its attractive merits,such as flexible signals configuration in multiple ***,commercial SDR equipment also has large spurious emissions in the Transmitting(Tx)*** paper presents a cascaded model for the Conducted Emission(CE)properties of a general SDR platform,which captures all the key components with high *** on a deeper understanding of the CE properties,a mitigation method is proposed for suppressing the spurious emissions of an SDR Tx *** method is based on an efficient vector signal cancellation scheme,in which multiple SDR channels are adopted to suppress the second-and third-order harmonic signals simultaneously.A hardware prototype with dual SDR channels is built and measured for *** results show that the suppression level of the third-order harmonic signal is 24 dB on average in the frequency range of 100 MHz to 3000 *** theoretic limit of the suppression level is related to the magnitude and phase errors,and the suppression level may be further improved by calibrating each SDR channel.

关键词： Cancellation Conducted Emission(CE) Harmonic suppression SDR Spurious emission

Generalization of quasi-Koszul algebras

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Applied Mathematics(A Journal of Chinese Universities) 2010年第1期25卷 117-126页

作者： xia qi Department of Mathematics Zhejiang University Hangzhou 310027 China

In this paper, we generalize two kinds of graded algebras, δ-Koszul algebras and Kp algebras, to the non-graded cases. The trivial modules of δ-Koszul algebras have pure resolutions, while those of Kp algebras admit non-pure resolutions. We provide necessary and sufficient conditions for a notherian semiperfect algebra either to be a quasi-δ-Koszul algebra or to be a quasi-Kp algebra.

关键词： Quasi-Koszul algebra Yoneda-Ext algebra semiperfect algebra.

On a New Hybrid Estimator for the Central Mean Space

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Journal of Systems Science & Complexity 2017年第1期30卷 111-121页

作者： xia qi DONG Yuexiao Department of Statistical Science Temple University USA.

Existing estimators of the central mean space are known to have uneven performances across different types of link functions. By combining the strength of the ordinary least squares and the principal Hessian directions, the authors propose a new hybrid estimator that successfully recovers the central mean space for a wide range of link functions. Based on the new hybrid estimator, the authors further study the order determination procedure and the marginal coordinate test. The superior performance of the hybrid estimator over existing methods is demonstrated in extensive simulation studies.

关键词： Marginal coordinate test order determination ordinary least squares principal Hessiandirections sufficient dimension reduction.

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SNCR烟气脱硝工艺在不同炉型上的应用

中国环保产业 2016年第10期 54-58页

作者：华玉龙袁瑞龙戚圣琦陈遐龄中国联合工程公司杭州310052

选择性非催化还原(SNCR)烟气脱硝工艺的效率完全依赖于温度窗口,不同炉型的适用性差别较大。结合多个工程案例,描述了SNCR工艺在循环流化床锅炉、煤粉炉、链条炉及其它炉型上的脱硝效果,分析了各种影响因素,为SNCR工艺在不同炉型中的应... 详细信息

选择性非催化还原(SNCR)烟气脱硝工艺的效率完全依赖于温度窗口,不同炉型的适用性差别较大。结合多个工程案例,描述了SNCR工艺在循环流化床锅炉、煤粉炉、链条炉及其它炉型上的脱硝效果,分析了各种影响因素,为SNCR工艺在不同炉型中的应用提供了参考。

关键词： SNCR 脱硝炉型温度窗口脱硝效率

General variational solution for seismic and static active earth pressure on rigid walls considering soil tensile strength cut-off

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第5期24卷 432-449页

作者： Shiguo xiaO Yuan qi Pan xia Key Laboratory of High-Speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 60031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Department of Geological Engineering Southwest Jiaotong UniversityChengdu 610031China

According to the limit equilibrium state of soils behind rigid walls and the pseudo-static approach,a general closed-form solution to seismic and static active earth pressure on the walls,which considers shear and tension failure of the retained soil,is put forward using a variational calculus *** application point of the active resultant force specified in the proposed method is explained with a clear physical meaning related to possible movement modes of the *** respect of the derived nine dependent equations reflecting the functional characteristics of the earth pressure,the proposed method can be performed easily via an implicit *** are 13 basic factors related to the retained soils,walls,and external loads to be involved in the proposed *** tension crack segment of the slip surface is obviously influenced by these parameters,apart from vertical seismic coefficient and geometric bounds of the surcharge,but the shear slip segment maintains an approximately planar shape almost uninfluenced by these ***,the proposed method quantitatively reflects that the resultant of the active earth pressure is always within a limited range under different possible movements of the same wall.

关键词： Active earth pressure Tensile strength cut-off Variational calculus method Pseudo-static method Strip surcharge

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乡镇中小学建筑的特点及抗震鉴定

山东建筑大学学报 2010年第3期25卷 285-289页

作者：李安起亓勇夏静邢建山东建筑大学建筑结构鉴定加固与改造山东省重点实验室山东济南250101

5.12汶川地震后,全国中小学建筑的抗震鉴定和加固成为各级政府的工作之重。以济南市某区属乡镇中小学为样本,分析了乡镇中小学建筑的特点;探讨了检测鉴定的顺序和方式;提出了一种用于楼梯间的组合构造柱;对《建筑抗震鉴定标准》GB50023... 详细信息

5.12汶川地震后,全国中小学建筑的抗震鉴定和加固成为各级政府的工作之重。以济南市某区属乡镇中小学为样本,分析了乡镇中小学建筑的特点;探讨了检测鉴定的顺序和方式;提出了一种用于楼梯间的组合构造柱;对《建筑抗震鉴定标准》GB50023—2009的第二级鉴定中的构造与抗震验算问题提出了建议。

关键词：乡镇中小学学校建筑抗震鉴定组合构造柱