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Detection of Flare Multiperiodic Pulsations in Mid-ultraviolet Balmer Continuum, Lyl Hard X-Ray, and Radio Emissions Simultaneously 期刊论文 OAI收割
The Astrophysical Journal, 2021, 卷号: 921, 页码: 179
作者: HXMT

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Solar flares Solar oscillations Solar ultraviolet emission Solar x-ray emission Solar radio emission 1496 1515 1533 1536 1522 Astrophysics - Solar and Stellar Astrophysics Abstract: Quasi-periodic pulsations (QPPs), which usually appear as temporal pulsations of the total flux, are frequently detected in the light curves of solar/stellar flares. In this study, we present the investigation of nonstationary QPPs with multiple periods during the impulsive phase of a powerful flare on 2017 September 6, which were simultaneously measured by the Hard X-ray Modulation Telescope (Insight-HXMT), as well as the ground-based BLENSW. The multiple periods, detected by applying a wavelet transform and Lomb-Scargle periodogram to the detrended light curves, are found to be ~20-55 s in the Ly`and mid-ultraviolet Balmer continuum emissions during the flare impulsive phase. Similar QPPs with multiple periods are also found in the hard X-ray emission and low-frequency radio emission. Our observations suggest that the flare QPPs could be related to nonthermal electrons accelerated by the repeated energy release process, i.e., triggering of repetitive magnetic reconnection, while the multiple periods might be modulated by the sausage oscillation of hot plasma loops. For the multiperiodic pulsations, other generation mechanisms could not be completely ruled out.

Parameter optimization of space truss and aerospace load viscoelastic damping composite structure 会议论文 OAI收割
2016 International Conference on Civil, Architecture and Environmental Engineering (ICCAE 2016), Taipei, Taiwan, November 4-6, 2016
作者: Wang P(王鹏); Zhang, Zhenwei; Luo HT(骆海涛)

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收藏 | 浏览/下载：120/0 | 提交时间：2017/11/15

viscoelastic damping aerospace acceptance truss acceleration applying constrained modulus stiffness

Method of tacit knowledge discovery based on domain knowledge under driven of problems (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Computer Science and Information Processing, CSIP 2012, August 24, 2012 - August 26, 2012, Xi'an, Shaanxi, China
作者: Wang Y.-C.; Wang Y.-C.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

Now most of the knowledge discoveries are using the data mining technology and driven by data. This kind of knowledge discovery can't finish the discovery exploration and applying of the tacit knowledge. According to the problem above this paper proposes a domain knowledge-based of problem driven tacit knowledge discovery method. This paper designs a S-K-T algorithm and the related problem-knowledge mining algorithm to get the domain knowledge semantic tree and the problem-domain knowledge tree and based on this through the spiral iteration to finish the discovery of the tacit knowledge under the driven of problems. 2012 IEEE.

The application of symmetrical equation of diffracted wavevectors in integral theory of gratings (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Advanced Engineering Materials and Technology, AEMT 2012, July 6, 2012 - July 8, 2012, Zhuhai, China
作者: Gao J.; Zhang F.; Zhang F.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

The integral theory for electromagnetic theory of gratings which has complex mathematical tool and long computation cost is needed to improve computing speed of the algorithm. A very shot-cut equation which is called symmetrical equation of diffracted wavevectors by us is presented. It makes the number of Green's function expansion terms shorter and simplifies the integral kernel by taking into account its symmetry. Take the grating in Littrow mount for computing example because of applying this equation the computation cost of integral theory which has good convergence is shorten to 1/2 to 2/5. This work modifies the integral theory and improves its computing speed. (2012) Trans Tech Publications Switzerland.

氢还原产电生物可渗透反应栅阳极反应特性研究 学位论文 OAI收割
硕士, 北京: 中国科学院研究生院, 2011
朱高英

收藏 | 浏览/下载：48/0 | 提交时间：2011/08/30

地下水氢还原产电生物可渗透反应栅（PREPRB）阳极反应特性外加电压煤焦油 groundwater proton reduction electricigenic permeable reactive barrier (PREPRB) anodic reaction characteristics applying voltage coal tar

The technique of camera scan control based on current loop control (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
作者: Liu Z.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

As the crucial structure of aerial camera sca reflector is always requested with high performance of control precision stable running and rapid responding. The paper introduces a kind of method about current loop control system which is based on position and velocity dual-closed loop control system. This method improves effectively the performance of velocity closed loop control system and amplifies the gain of low frequency. The results show applying these control methods the influence of the torque ripple has decrease 50% and the compensation rate precsion has promoted double. 2011 IEEE.

The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Li Y.; Zhang H.; Zhang H.; Li Y.; Li Y.

收藏 | 浏览/下载：43/0 | 提交时间：2013/03/25

As a result of the radar system got interferenced or in the state of half silent it can cause the guided precision drop badly In the modern electronic warfare therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings but when interference is in the process of radar leading especially the electro-optical equipment is influenced by the roll pitch and yaw rotation it can affect the target appear outside of the field of optoelectronic devices for a long time so the infrared optoelectronic equipment can not exert the superiority and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

氮肥用量与施用时期对棉花生长发育及土壤矿质氮含量的影响[J] 期刊论文 OAI收割
西北农林科技大学学报(自然科学版), 2011, 卷号: 11, 页码: 103-109
作者: 胡明芳; 田长彦; 王林霞; 中国科学院新疆生态与地理研究所

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收藏 | 浏览/下载：16/0 | 提交时间：2017/12/29

氮肥用量施用时期棉花棉铃矿质氮 Nitrogen Rate Applying Time Cotton Boll Mineral Nitrogen

An adaptive image contrast enhancement based on differential evolution (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Congress on Image and Signal Processing, CISP 2010, October 16, 2010 - October 18, 2010, Yantai, China
Yang Q.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

Tubbs proposed a regularized incomplete beta function to represent some nonlinear transform functions most commonly used in image contrast enhancement. But how to define the coefficients of the beta function adaptively is still a problem. Applying the differential evolution in image contrast enhancement we utilize the global quickly search ability of the differential evolution algorithm adaptive mutation search at last searches the optimal values of beta function and gets an adaptive contrast enhanced image. To avoid trapping into local optimum a chaotic differential evolution algorithm is proposed. Experimental results show that the proposed algorithm can find the global optimal in few iterations and save largely computational time and complexity. 2010 IEEE.

Electric-field-induced effective anchoring energy in nematic liquid crystal (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Display and Photonics, July 12, 2010 - July 13, 2010, Nanjing, China
Ye W.; Zhang Z.; Xing H.; Yang G.; Chen G.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

Electric-field-induced effective anchoring energy in nematic liquid crystal is investigated taking surface and flexoelectric polarization into consideration. The analytical expressions of effective anchoring energy for both bottom and upper substrate containing these two polarizations are derived. The effective anchoring strength for both bottom and upper substrate is also obtained by means of a systematic method which is relevant to magnitude of two polarizations and determined by the applied voltage U. Applying the obtained expressions into an original weak anchoring hybrid aligned nematic cell the effective anchoring strength are determined with the different magnitudes of two polarizations and the different applied voltage U.