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Maximum flux density of the gyrosynchrotron spectrum in a nonuniform source

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 475-484页

作者： ai-hua Zhou Rong-Chuan Wang Cheng-Wen Shao Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The maximum flux density of a gyrosynchrotron radiation spectrum in a magnetic diploe model with self absorption and gyroresonance is calculated. Our calculations show that the maximum flux density of the gyrosynchrotron spectrum increases with increasing low-energy cutoff, number density, input depth of energetic electrons, magnetic field strength and viewing angle, and with decreasing energy spectral index of energetic electrons, number density and temperature of thermal electrons. It is found that there are linear correlations between the logarithms of the maximum flux density and the above eight parameters with correlation coefficients higher than 0.91 and fit accuracies better than 10%. The maximum flux density could be a good indicator of the changes of these source parameters. In addition, we find that there are very good positive linear correlations between the logarithms of the maximum flux density and peak frequency when the above former five parameters vary respectively. Their linear correlation coefficients are higher than 0.90 and the fit accuracies are better than 0.5%.

关键词： Sun flare-Sun radio emission-Sun maximum flux

Study of temporal evolution of emission spectrum in a steeply rising submillimeter burst

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Research in Astronomy and Astrophysics 2016年第1期16卷 67-72页

作者： Jian-Ping Li ai-hua Zhou Xin-Dong Wang Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of Sciences Nanjing 210008 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China School of Public Administration Hohai University Nanjing 210098 China

The temporal evolution of a spectrum during a steeply rising submillimeter（THz） burst that occurred on 2003 November 2 was investigated in detail for the first *** show that the flux density of the THz spectrum increased steeply with frequency above 200 *** average rising rates reached a value of 235 sfu GHz^（-1）（corresponding to spectral index α of 4.8） during the *** flux densities reached about 4 000 and 70 000 sfu at 212 and 405 GHz at the maximum phase,*** emissions at 405 GHz maintained such a continuous high level that they largely exceeded the peak values of the microwave（MW） spectra during the main *** studies suggest that only energetic electrons with a low-energy cutoff of~ 1 MeV and number density of ~ 10~6-10~8 cm^（-3） can produce such a strong and steeply rising THz component via gyrosynchrotron radiation based on numerical simulations of burst spectra in the case of a nonuniform magnetic *** electron number density N,derived from our numerical fits to the THz temporal evolution spectra,increased substantially from 8 ×10~6 to 4 × 10~8 cm^（-3）,i.e.,the N value increased 50 times during the rise *** the decay phase it decreased to 7 ×10~7 cm^（-3）,i.e.,it decreased by about five times from the maximum *** total electron number decreased an order of magnitude from the maximum phase to the decay ***,the variation in amplitude of N is only about one time in the MW emission source during this burst,and the total electron number did not decrease but increased by about 20%during the decay ***,we find that the THz source radius decreased by about 24%while the MW source radius,on the contrary,increased by 28%during the decay phase.

关键词： Sun: submillimeter burst -- Sun: energetic electrons -- Sun: radio source size

Selfinjective Koszul Algebras of Finite Complexity

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2179-2198页

作者： Jin Yun GUO ai hua LI Qiu Xian WU Department of Mathematics Xiangtan University Xiangtan 411105 P. R. China Department of Mathematics Hu'nan Normal University Changsha 410081 P. R. China

In this paper, we study selfinjective Koszul algebras of finite complexity. We prove that the complexity is a nonnegative integer when it is finite; and that the category Yt of modules with complexity less or equal to t, is resolving and coresolving. We show that for each 0 ≤ 1 ≤ m there exist a family of modules of complexity 1 parameterized by G（l, m）, the Grassmannian of l-dimensional subspaces of an m-dimensional vector space V, for the exterior algebra of V. Using complexity, we also give a new approach to the representation theory of a tame symmetric algebra with vanishing radical cube over an algebraically closed field of characteristic 0, via skew group algebra of a finite subgroup of SL（2, C） over the exterior algebra of a 2-dimensional vector space.

关键词： selfinjective Koszul algebra complexity skew group algebra tame symmetric algebra

Diagnostics from three rising submillimeter bursts

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Research in Astronomy and Astrophysics 2016年第2期16卷 97-104页

作者： ai-hua Zhou Jian-Ping Li Xin-Dong Wang Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of Sciences Purple Mountain Observatory Chinese Academy of Sciences School of Public Administration Hohai University

In this paper we investigate three novel rising submillimeter （THz） bursts that occurred sequen- tially in Super Active Region NOAA 10486. The average rising rate of the flux density above 200 GHz is only 20 sfu GHz-1 （corresponding to spectral index α of 1.6） for the THz spectral components of the 2003 October 28 and November 4 bursts, but it attained values of 235 sfu GHz-1 （α = 4.8） in the 2003 November 2 burst. The steeply rising THz spectrum can be produced by a population of highly relativistic electrons with a low-energy cutoff of 1 MeV, but it only requires a low-energy cutoff of 30 keV for the two slowly rising THz bursts, via gyrosynchrotron （GS） radiation based on our numerical simulations of burst spectra in the magnetic dipole field case. The electron density variation is much larger in the THz source than in the microwave （MW） source. It is interesting that the THz source radius decreased by 20%-50% during the decay phase for the three events, but the MW source increased by 28% for the 2003 November 2 event. In the paper we will present a formula that can be used to calculate the energy released by ultrarel- ativistic electrons, taking the relativistic correction into account for the first time. We find that the energy released by energetic electrons in the THz source exceeds that in the MW source due to the strong GS radi- ation loss in the THz range, although the modeled THz source area is 3-4 orders smaller than the modeled MW source one. The total energies released by energetic electrons via the GS radiation in radio sources are estimated, respectively, to be 5.2 × 10^33, 3.9 × 10^33 and 3.7 × 10^32 erg for the October 28, November 2 and 4 bursts, which are 131, 76 and 4 times as large as the thermal energies of 2.9 × 10^31, 2.1 × 10^31 and 5.2 × 10^31 erg estimated from soft X-ray GOES observations.

关键词： Sun submillimeter emission -- Sun energetic electrons -- Sun radio source environment

An active reflector antenna using a laser angle metrology system

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Research in Astronomy and Astrophysics 2012年第6期12卷 713-722页

作者： Yong Zhang Jie Zhang De-hua Yang Guo-hua Zhou ai-hua Li Guo-Ping Li National Astronomical Observatories/Nanjing Institute of Astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics ＆ Technology Nanjing Institute of Astronomical Optics＆ Technology Chinese Academy of Sciences Nanjing 210042 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

An active reflector is one of the key technologies for constructing large telescopes, especially for millimeter/sub-millimeter radio telescopes. This article in- troduces a new efficient laser angle metrology system for an active reflector antenna on large radio telescopes. Our experiments concentrate on developing an active reflec- tor for improving the detection precisions and the maintenance of the surface shape in real time on the 65-meter prototype radio telescope constructed by Nanjing Institute of Astronomical Optics and Technology （NIAOT; http：//***/）. The test results indicate that the accuracy of the surface shape segmentation and maintenance has the dimensions of microns, and the time-response can be on the order of minutes. Our efforts proved to be workable for sub-millimeter radio telescopes.

关键词： radio radiation -- telescopes -- adaptive optics -- sub-millimeter

“分解-校正-集成”模式下基于深度信念网络模型的径流预测

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长江科学院院报 2024年第5期41卷 35-44页

作者：钱玉霞陈伏龙何朝飞龙爱华孙怀卫吕廷波石河子大学水利建筑工程学院新疆石河子832000 寒旱区生态水利工程兵团重点实验室新疆石河子832000 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 华中科技大学土木与水利工程学院武汉430074

精准的短期径流预测可为流域内水资源规划、防洪调度及抗旱减灾工作提供重要的科学依据。为减小模型的系统误差,提高径流预测精度,在“分解-集成”模式的基础上提出“分解-校正-集成”框架,构建EEMD-DBN-EnKF、VMD-DBN-EnKF模型。利用... 详细信息

精准的短期径流预测可为流域内水资源规划、防洪调度及抗旱减灾工作提供重要的科学依据。为减小模型的系统误差,提高径流预测精度,在“分解-集成”模式的基础上提出“分解-校正-集成”框架,构建EEMD-DBN-EnKF、VMD-DBN-EnKF模型。利用集合卡尔曼滤波数据同化算法对偏离实测径流过大的分量校正以降低分解子序列在预测中产生的系统误差,并与未修正的EEMD-DBN、VMD-DBN模型及单一DBN模型进行了对比分析。结果表明:基于模态分解的组合模型较单一模型RMSE减小了至少23%,NSE与R^(2)增加了21%以上;基于径流分量校正的组合模型相较于模态分解的组合模型各评价系数有所提升,其中VMD-DBN-EnKF预测模型误差最小,效果最优,NSE与R^(2)达到0.89以上,其次依次为EEMD-DBN-EnKF>VMD-DBN>EEMD-DBN。综上“分解-校正-集成”模式的预测框架在玛纳斯河流域具有良好的适用性,可为玛纳斯河径流短期预报提供技术支持。

关键词：模态分解深度信念网络集合卡尔曼滤波径流预测组合模型

Different frequencies of repetitive transcranial magnetic stimulation combined with local injection of botulinum toxin type A for post-stroke lower limb spasticity:study protocol for a prospective,single-center,non-randomized,controlled clinical trial

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Neural Regeneration Research 2022年第11期17卷 2491-2496页

作者： Yang Shao Yang Yang Yong-Xin Sun ai-hua Xu Department of Rehabilitation Medicine the First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

No definite consensus has currently been reached regarding the safety and efficacy of low-or high-frequency repetitive transcranial magnetic stimulation in the treatment of post-stroke muscle *** latest research indicates that when combined with local injections of botulinum toxin type A,it is more effective on post-stroke muscle spasticity than local injections of botulinum toxin type A *** designed a prospective,single-center,non-randomized,controlled clinical trial to investigate the safety and effica cy of different frequencies of repetitive transcranial magnetic stimulation combined with local injections of botulinum toxin type A in treating post-stroke lower limb muscle spasticity to determine an optimal therapeutic *** trial will enroll 150 patients with post-stroke muscle spasticity admitted to the Department of Rehabilitation Medicine at the First Affiliated Hos pital of China Medical Unive *** enrolled patients will undergo ro utine rehabilitation training and will be divided into five groups in-30 per group) according to the particular area of cerebral infa rction and treatment methods.G roup A:Patients with massive cerebral infarction will be given local injections of botulinum toxin type A and low-frequency(1 Hz)repetitive transcranial magnetic stimulation on the contralate ral side;G roup B:Patients with non-massive cerebral infarction will be given local injections of botulinum toxin type A and high-frequency(10-20 Hz) re petitive transcranial magnetic stimulation on the affected side;G roup C:Patients with massive/non-massive cerebral infarction will be given local injections of botulinum toxin type A;G roup D:Patients with massive cerebral infarction will be given low-frequency(1 Hz) repetitive transcranial magnetic stimulation on the contralate ral side;and G roup E:Patients with non-massive cerebral infa rction will be given high-frequency(10-20 Hz) repetitive transcranial magnetic stimulation on the affected ***

关键词： Botulinum toxin type A exercise lower limbs muscle spasticity neural regeneration rehabilitation training repetitive transcranial magnetic stimulation stroke

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颌面部多发性外伤患者的护理实践

中国医疗美容 2024年第5期14卷 88-91页

作者：谢爱华王功磊张丝雨漯河市中医院河南漯河462000

目的探析护理干预作用于颌面部多发性外伤中的实践效果。方法本院自2021年1月起开始收集颌面部多发性外伤的病例资料,至2023年止共纳入81例,均采取护理干预;观察患者护理后的口腔功能、创口愈合、美观度等情况。结果本组81例患者中,创... 详细信息

目的探析护理干预作用于颌面部多发性外伤中的实践效果。方法本院自2021年1月起开始收集颌面部多发性外伤的病例资料,至2023年止共纳入81例,均采取护理干预;观察患者护理后的口腔功能、创口愈合、美观度等情况。结果本组81例患者中,创口愈合率为95.06%(77/81);口腔功能恢复的总有效率为96.30%(78/81)。护理干预后患者的红色美学指数(英简PES)为(10.82±0.58)分较护理前的(4.22±0.32)分明显提高(P<0.05)。在生活质量方面,护理干预后患者各项生活质量评分较护理前显著提高(P<0.05)。结论护理干预作用于颌面部多发性外伤患者中,可有效促进颌面部的创口愈合,口腔功能恢复效果较好,提升创面美观度。

关键词：护理干预颌面部多发性外伤创面

Some Strong Deviation Theorems for Dependent Continuous Random Sequence

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Chinese Quarterly Journal of Mathematics 2010年第4期25卷 572-577页

作者： FAN ai-hua Faculty of Mathematics and Physics Anhui University of TechnologyMa＇anshan 243002China

Let {Xn,n ≥ 1} be a sequence of arbitrary continuous random variables,we introduce the notion of limit asymptotic logarithm likelihood ratio r（ω）,as a measure of dissimilarity between probability measure P and reference measure *** get some strong deviation theorems for the partial sums of arbitrary continuous random variables under Chung-Teicher＇s type conditions[6-7].

关键词： limit asymptotic logarithm likelihood ratio random sequence strong deviation theorem