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On joint analysing XMM-NuSTAR spectra of active galactic nuclei
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作者 Jialai Kang Junxian Wang 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期19-33,18,I0002,共17页
A recently released XMM-Newton note revealed a significant calibration issue between nuclear spectroscopic telescope array(NuSTAR)and XMM-Newton European Photon Imaging Camera(EPIC)and provided an empirical correction... A recently released XMM-Newton note revealed a significant calibration issue between nuclear spectroscopic telescope array(NuSTAR)and XMM-Newton European Photon Imaging Camera(EPIC)and provided an empirical correction to the EPIC effective area.To quantify the bias caused by the calibration issue in the joint analysis of XMM-NuSTAR spectra and verify the effectiveness of the correction,in this work,we perform joint-fitting of the NuSTAR and EPIC-pn spectra for a large sample of 104 observation pairs of 44 X-ray bright active galactic nuclei(AGN).The spectra were extracted after requiring perfect simultaneity between the XMM-Newton and NuSTAR exposures(merging good time intervals(GTIs)from two missions)to avoid bias due to the rapid spectral variability of the AGN.Before the correction,the EPIC-pn spectra are systematically harder than the corresponding NuSTAR spectra by■subsequently yielding significantly underestimated cutoff energy E_(cut)and the strength of reflection component R when performing joint-fitting.We confirm that the correction is highly effective and can commendably erase the discrepancy in best-fitΓ,E_(cut),and R.We thus urge the community to apply the correction when joint-fitting XMM-NuSTAR spectra,but note that the correction is limited to 3–12 keV and therefore not applicable when the soft X-ray band data are included.Besides,we show that as merging GTIs from two missions would cause severe loss of NuSTAR net exposure time,in many cases,joint-fitting yields no advantage compared with utilizing NuSTAR data alone.Finally,We present a technical note on filtering periods of high background flares for XMM-Newton EPIC-pn exposures in the small window(SW)mode. 展开更多
关键词 active galactic nuclei X-ray spectroscopy XMM-NEWTON NuSTAR cross-calibration issue
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《汉书·扬雄传》旧注“超,速也”质疑 被引量:1
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作者 苏芃 《语言科学》 CSSCI 北大核心 2009年第6期667-669,共3页
"超"字在《汉语大字典》、《汉语大词典》中皆有"速"的义项,设立这一义项主要依据的书证都是《汉书·扬雄传》颜注引应劭语"超,速也",而此处的"速"字实际上是"远(遠)"字的讹误。
关键词 () 讹字
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Chemical constituents from the roots of Polygala sibirica L. 被引量:1
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作者 周雨虹 姜勇 +2 位作者 温晶 陈玉平 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第2期148-152,共5页
To investigate the chemical constituents of the roots ofPolygala sibirica L. The separation and purification were performed by solvent extraction and repeated chromatography with silica gel, Sephadex LH-20, ODS column... To investigate the chemical constituents of the roots ofPolygala sibirica L. The separation and purification were performed by solvent extraction and repeated chromatography with silica gel, Sephadex LH-20, ODS columns, and semiprep. HPLC. The structures were elucidated by spectral analysis. Twelve known compounds were isolated and identified as tenuifoliside A (1), tenuifoliside B (2), glomeratose A (3), 3',6-disinapoyl sucrose (4), sibiricose A5 (5), sibiricose A6 (6), sibiricose A1 (7), sibiricose A2 (8), polygalatenoside E (9), 1-O-L-arabinopyranosyl-O-(6→1)-β-D-glucopyranosyl-salicylate (10), canthoside A (11), and methyl- 3,4,5-trimethoxycinnamate (12). Compound 11 was obtained from genus Polygala for the first time, and compounds 2, 9, 10 and 12 were isolated from this plant for the first time. 展开更多
关键词 POLYGALACEAE Polygala sibirica L. Chemical constituents
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NEW REMOTE USER AUTHENTICATION SCHEME USING SMART CARD 被引量:2
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作者 杨君佐 王永建 周渊 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期187-192,共6页
Because the modified remote user authentication scheme proposed by Shen, Lin and Hwang is insecure, the Shen-Lin-Hwang' s scheme is improved and a new secure remote user authentication scheme based on the bi- linear ... Because the modified remote user authentication scheme proposed by Shen, Lin and Hwang is insecure, the Shen-Lin-Hwang' s scheme is improved and a new secure remote user authentication scheme based on the bi- linear parings is proposed. Moreover, the effectiveness of the new scheme is analyzed, and it is proved that the new scheme can prevent from all kinds of known attack. The one-way hash function is effective in the new scheme. The new scheme is proved that it has high effectiveness and fast convergence speed. Moreover, the ap- plication of the new scheme is easy and operational. 展开更多
关键词 remote user authentication password authentication remote login bilinear pairings
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Conceptual Architecture for Remotely Piloted Operation Mode in Commercial Aircraft 被引量:1
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作者 LUO Yue WANG Miao +1 位作者 XIAO Gang WANG Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第2期274-287,共14页
With the increasing civil aviation passengers and the rapid development of aviation logistics,the study on remotely piloted operation(RPO)mode has received extensive attention.RPO mode constructs the piloting decision... With the increasing civil aviation passengers and the rapid development of aviation logistics,the study on remotely piloted operation(RPO)mode has received extensive attention.RPO mode constructs the piloting decisionmaking mode which involves the tripartite collaboration among airborne automatic/autonomous system,remote ground-based crews and air traffic control.In this paper,we describe the organizing architecture for commercial remotely piloted aircraft(CRPA)system and its components.Compared with the current operation mode,the new air-ground collaborative decision-making mode has been established with six different situations based on the type of the flight and the condition of the remote pilot.Taking airport surface operation as an experimental example,we model the airport surface operation process and compare the advantages and disadvantages between RPO mode and the current dual-pilot mode from the perspectives of time and operation coverage,and draw conclusions that RPO mode can basically cover the flight operations of the dual-pilot,improve the accuracy of pilot operations and greatly reduce response time by 48%in pre-flight inspection.The above research would be the foundation for the RPO development of commercial aircraft in China. 展开更多
关键词 remotely piloted operations(RPO) commercial remotely piloted aircraft(CRPA) airborne automatic/autonomous system flight process
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Application of remote monitoring technology in landslides in the Luoshan mining area 被引量:30
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作者 HE Man-chao TAO Zhi-gang ZHANG Bin 《Mining Science and Technology》 EI CAS 2009年第5期609-614,共6页
With the scale extending of mining, the landslide disaster in the earth’s surface will become more and more serious, and these landslide disasters are being threatened to the sustainable safe mining of the undergroun... With the scale extending of mining, the landslide disaster in the earth’s surface will become more and more serious, and these landslide disasters are being threatened to the sustainable safe mining of the underground mine and the open-pit mine. Based on the theory that sliding force is greater than the shear resistance (resisting force) at the potential slip surface is the necessary and sufficient condition to occur the landslide as the sliding criterion, the principle and method for sliding force remote monitoring is presented, and the functional relationship between the human mechanical quantity and the natural sliding force is derived, hereby, the natural sliding force can be calculated according to the human mechanical quantity. Based on above principle and method, a new system of landslide remote monitoring is designed and 53 systems are installed on the landslide body in the Luoshan mining area, which make up the landslide remote monitoring network. According to the results of field test around 8 months, monitoring curves between sliding force and time are obtained, which can describe and forecast the develop trend of landslide. According to above analysis, the results show that this system has some following advantages: (1) real-time monitoring; (2) remote intelligent transmission; (3) landslides early warning. 展开更多
关键词 mine exploitation landslide disaster sliding force monitoring forecasting and early warning
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QoE Assessment in Haptic Teleoperation Systems: Position-Position versus Position-Force
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作者 Junya Osada Yutaka Ishibashi Norishige Fukushima Shinji Sugawara 《Computer Technology and Application》 2012年第11期756-764,共9页
In this paper, we make a comparison of haptic control schemes (position-position and position-force control schemes) for two haptic teleoperation systems by QoE (quality of experience) assessment. One is a remote ... In this paper, we make a comparison of haptic control schemes (position-position and position-force control schemes) for two haptic teleoperation systems by QoE (quality of experience) assessment. One is a remote control system with haptic media and video. In the system, we can write characters by controlling a haptic interface device at a remote place with another haptic interface device while watching video. The other is a remote instruction system with haptic media, video and voice. By using the system, a teacher can actively write characters and teach a student how to write the characters. The student can also write characters actively, and the teacher can confirm how the student writes the characters. We investigate the influences of network delay on QoE for the two systems with the two haptic control schemes. 展开更多
关键词 Remote control system remote instruction system haptic control schemes haptic media video VOICE QoE (quality of experience) network delay.
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The Remote Monitoring System Research Based on Embedded Web Server
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作者 Ying ZHOU 《International Journal of Technology Management》 2015年第6期101-103,共3页
The paper analyze and design and implement a remote control system based on embedded web server network. A computer network remote control system mainly includes server, client and the control information. Server regi... The paper analyze and design and implement a remote control system based on embedded web server network. A computer network remote control system mainly includes server, client and the control information. Server registration information realize the user command; client provides network hardware, software and other system resources, the system response message and then feedback service instruction. The research results show that, the embedded web server can be assigned to the field device user information through the browser, field device data also can access to the browser through the web server. In order to achieve remote monitoring, control, diagnostics and configuration of the equipment. 展开更多
关键词 Remote Control Embedded system SOCKET Communication protocol
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Research on the Modern Distance Education Learning Center Service Quality Factors and Framework
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作者 Wenjun Liu 《International Journal of Technology Management》 2016年第10期15-17,共3页
The modem distance education along with one new educational mode that the development of enterprise group has, it takes the modem distance education as the principal means that, imparts and studies independently throu... The modem distance education along with one new educational mode that the development of enterprise group has, it takes the modem distance education as the principal means that, imparts and studies independently through the correspondence course and other educational modes, can effectively take advantage of the educational resources. In the era of knowledge economy, the high-quality and perfect educational system is the biggest resources. But the educational quality has decided the altitude of education. But the research distance learning service enhances the student degree of satisfaction and promotion service level to have the high research value regarding the distance learning organization. Based on our country modem distance education development level, should be centered on improving the grade of service, strengthens the teaching service concept that realizes multi-resource sharing the strategic concept. 展开更多
关键词 EDUCATION Quality of service System research
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厚朴炙远志炮制品的安神和祛痰作用研究 被引量:24
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作者 马骁 王建 +4 位作者 黄聪 罗凤娟 郑新光 曾南 夏厚林 《中药药理与临床》 CAS CSCD 北大核心 2013年第1期90-93,共4页
目的:考察厚朴炙远志炮制品对小鼠的镇静催眠、镇咳祛痰作用的影响。方法:采用戊巴比妥钠协同小鼠催眠实验与小鼠自主活动实验,对比炮制品与单味远志、单味厚朴之间的镇静催眠药效;采用氨水诱导法致小鼠咳嗽实验和小鼠气管酚红排泌的祛... 目的:考察厚朴炙远志炮制品对小鼠的镇静催眠、镇咳祛痰作用的影响。方法:采用戊巴比妥钠协同小鼠催眠实验与小鼠自主活动实验,对比炮制品与单味远志、单味厚朴之间的镇静催眠药效;采用氨水诱导法致小鼠咳嗽实验和小鼠气管酚红排泌的祛痰实验,对比炮制品与单味远志、单味厚朴之间的镇咳祛痰药效。结果:与空白组相比,优选出的炮制品高剂量(30g/kg)能显著增强对小鼠戊巴比妥钠协同催眠的作用,并显著抑制小鼠自主活动,极显著延长小鼠的咳嗽潜伏时间及减少小鼠咳嗽的次数,并显著增加小鼠气管的酚红吸光度,炮制品的药效在7.5g/kg至30g/kg的范围内成剂量依赖关系。结论:优选出的厚朴炙远志炮制品具有镇静催眠、镇咳祛痰作用。 展开更多
关键词 厚朴炙 镇静催眠 镇咳祛痰 厚朴
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Isolation of flavonoids from the aerial parts of Polygala tenuifolia Willd.and their antioxidant activities 被引量:14
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作者 史天星 李宇光 +1 位作者 姜勇 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第1期36-39,共4页
The aim of this study was to isolate the chemical constituents of the aerial parts of Polygala tenuifolia Willd. and to determine their antioxidant activities. Ten flavonoids were isolated and purified by silica gel, ... The aim of this study was to isolate the chemical constituents of the aerial parts of Polygala tenuifolia Willd. and to determine their antioxidant activities. Ten flavonoids were isolated and purified by silica gel, Sephadex LH-20, and ODS column chromatography, and semi-preparative HPLC. Their structures were elucidated by spectroscopic analysis and identified as isorhamnetin-3-O-13-D-glucopyranoside (1), isorhamnetin-3-O-13-D-galactopyranoside (2), quercetin-3-O-13-o-glucopyranosyl (1--*2)-I^-D-galactopyranoside (3), quercetin-3-O-13-O-glucopyranosyl (1---~2)-13-D-glucopyranoside (4), linarin (5), quercetin-3-O- 13-D-glucopyranoside (6), 5,7-dihydroxy-8-methxoyflavone-7-O-13-o-glucuronoside (7), isorhamnetin (8), kaempferol (9) and quercetin (10). All these compounds were isolated from this plant for the first time, and compounds 1-5 and 7 were isolated from the genus of Polygala for the first time. The antioxidant activities of the isolated compounds were evaluated by DPPH free radical scavenging assay, and compounds 3, 4, 6, 8, 9 and 10 showed potent antioxidant activities. 展开更多
关键词 POLYGALA Polygala tenuifolia Aerial parts FLAVONOIDS Antioxidant activity
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Chemical constituents from the roots of Polygala wattersii Hance 被引量:6
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作者 周雨虹 郭强 +1 位作者 姜勇 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2014年第10期723-730,共8页
Abstract: To investigate the chemical constituents of the roots of Polygala wattersii Hance, the separation and purification were performed by solvent extraction and repeated column chromatography (CC) on silica ge... Abstract: To investigate the chemical constituents of the roots of Polygala wattersii Hance, the separation and purification were performed by solvent extraction and repeated column chromatography (CC) on silica gel, Sephadex LH-20 and macroporous resin D101, preparative TLC and semi-preparative HPLC. The structures were identified by spectroscopic analysis and comparison of their 1H and 13C NMR data with those reported in literatures. Twenty-three known compounds, including eleven xanthones (1-11), nine sugar esters (12-20), two triterpenoid saponins (21 and 22) and one phenylpropanoid (23) were isolated and their structures were identified as 1,3-dihydroxyxanthone (1), 1-hydroxy-3-methoxyxanthone (2), 1,3-dihydroxy-2-methoxyxanthone (3), 1,3,7-trihydroxy-2- methoxyxanthone (4), 1,3,6-trihydroxy-2,7-dimethoxyxanthone (5), 1,6,7-trihydroxy-2,3-dimethoxyxanthone (6), 1,7-dihydroxy- 2,3-methylenedioxyxanthone (7), 1,7-dimethoxyxanthone (8), 1,2,3-trimethoxyxanthone (9), 1-methoxy-2,3-methylenedioxyxanthone (10), 6-hydroxy-0-methoxy-2,3-methylenedioxyxanthone (11), 3'-O-feruloyl-6-O-acetyl sucrose (12), arillatose B (13), sibricose A5 (14), sibricose A6 (15), 3',6-di-O-sinapoyl sucrose (16), tenufoliside A (17), 3'-O-3,4,5-trimethoxycinnamoyl-6-O-p-methoxybenzoyl sucrose (18), glomeratose A (19), 1-O-p-coumaroyl-D-glucopyranose (20), bayogenin-3-O-glucoside (21), tenufolin (22), and sinapic acid (23). Among them, compounds 2 and 12 were obtained from genus Polygala for the first time, and except compound 16, all others were isolated from this species for the first time. 展开更多
关键词 POLYGALACEAE Polygala wattersii Hance Chemical constituents XANTHONES Sugar esters
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Determination of tenuifolin in Polygalae Radix from different regions by RF-HPCE 被引量:1
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作者 郝增燕 王洁 +1 位作者 张一鸣 陈安家 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第4期342-346,共5页
A simple,low-cost and effective reverse flow-high performance capillary electrophoresis(RF-HPCE)method was developed for the separation and determination of tenuifolin in Polygalae Radix.Through optimization of sepa... A simple,low-cost and effective reverse flow-high performance capillary electrophoresis(RF-HPCE)method was developed for the separation and determination of tenuifolin in Polygalae Radix.Through optimization of separation conditions, a buffer of 50 mmol/L borax containing methanol(65:35,v/v)was selected for the separation of analytes.Regression equation revealed good linear relationship between peak area and concentration of the analyte in the range of 0.0563-0.9000 mg/mL (r=0.9988).The recoveries ranged from 99.50%-104.7%.The results indicated that this method is simple,rapid and accurate. It can be used for the quality control of Polygalae Radix. 展开更多
关键词 RF-HPCE TENUIFOLIN Polygalae Radix
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Mo/Si multilayers used for the EUV normal incidence solar telescope 被引量:4
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作者 LIU Zhen YANG Lin +2 位作者 CHEN Bo CHEN Bin CAO JianLin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第3期406-410,共5页
This paper first reviews an EUV normal incidence solar telescope that we have developed in our lab. The telescope is composed of four EUV telescopes and the operation wavelengths are 13.0 nm, 17.1 nm, 19.5 nm, and 30.... This paper first reviews an EUV normal incidence solar telescope that we have developed in our lab. The telescope is composed of four EUV telescopes and the operation wavelengths are 13.0 nm, 17.1 nm, 19.5 nm, and 30.4 nm. These four wavelengths, fundamental to the research of the solar activity and the atmosphere dynamics, are always chosen by the EUV normal incidence solar telescope. In the EUV region, almost all materials have strong absorption, so optics used in this region must be coated by the multilayer. The Mo/Si multilayers used for the EUV normal incidence solar telescope are designed and fabricated by the magnetron sputtering coating machine. The characteristics of these multilayers, such as reflectivity and thermal stability at wavelengths of 13.0 nm, 17.1 nm, 19.5 nm and 30.4 nm, are also described. All the multilayers were measured by a hard X-ray diffractometer (XRD) and an EUV/soft X-ray reflectometer (EXRR) before and after heating (in a vacuum chamber) at 100℃ for 24 hours and at 200℃ for 1 hour and 4 hours. The results show that Mo/Si multilayers have high reflectivity at 13.0 nm, 17.1 nm, and 19.5 nm but low at 30.4 nm. We found no change in the reflectivity and center wavelength of these multilayers by comparing the reflectivity curves before and after heating. This suggests the thermal stability of Mo/Si multilayers may meet our requirement in future solar observation missions. 展开更多
关键词 EUV solar telescope multilayer reflectivity thermal stability
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Infrared-controlled programmable metasurface 被引量:9
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作者 Ya-Lun Sun Xin-Ge Zhang +2 位作者 Qian Yu Wei-Xiang Jiang Tie-Jun Cui 《Science Bulletin》 SCIE EI CAS CSCD 2020年第11期883-888,M0003,共7页
Programmable metasurface enables controlling electromagnetic (EM) waves in real time. By programming the states of active device embedded in metasurface element, the EM properties of the digital metasurface can be cha... Programmable metasurface enables controlling electromagnetic (EM) waves in real time. By programming the states of active device embedded in metasurface element, the EM properties of the digital metasurface can be changed quickly without redesigning their structures. However, large numbers of long-distance wires are required to connect the programmable metasurface to provide the coded signals from field programmable gate array (FPGA) when controlling the metasurface at a long distance, which is complicated and inconvenient. Here, we propose an infrared-controlled programmable metasurface that can be programmed remotely. The infrared transceiver is able to switch the coding sequences stored in the FPGA controller, thus controlling the voltage on the varactors integrated in the metasurface. Experiment is performed at microwave frequencies, and the measured results verify that the scattering beams of the metasurface sample can be changed remotely by using infrared ray. The proposed infrared-controlled programmable metasurface opens up avenues for constructing a new class of remotely-tuning dynamic metasurfaces. 展开更多
关键词 Infrared-controlled programmable metasurfaces Remotely-tuning Beam splitting Beam scanning
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