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Characteristic modules and tensor products over quasi-hereditary algebras
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作者 Yue-hui ZHANG Shi-ying SHEN Ping-kai YE 《Science China Mathematics》 SCIE 2007年第8期1129-1140,共12页
Let A be a monomial quasi-hereditary algebra with a pure strong exact Borel subalgebra B.It is proved that the category of induced good modules over B is contained in the category of good modules over A;that the chara... Let A be a monomial quasi-hereditary algebra with a pure strong exact Borel subalgebra B.It is proved that the category of induced good modules over B is contained in the category of good modules over A;that the characteristic module of A is an induced module of that of B via the exact functor-(?)_B A if and only if the induced A-module of an injective B-module remains injective as a B-module.Moreover,it is shown that an exact Borel subalgebra of a basic quasi-hereditary serial algebra is right serial and that the characteristic module of a basic quasi-hereditary serial algebra is exactly the induced module of that of its exact Borel subalgebra. 展开更多
关键词 quasi-hereditary algebra monomial algebra exact Borel subalgebra good module characteristic module 16D25 16G10 17B10
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Characteristic Modules of Dual Extensions and Grobner Bases
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作者 Yun Ge XU Long Cai LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第6期1119-1130,共12页
Let C be a finite dimensional directed algebra over an algebraically closed field k and A=A(C) the dual extension of C.The characteristic modules of A are constructed explicitly for a class of directed algebras,which ... Let C be a finite dimensional directed algebra over an algebraically closed field k and A=A(C) the dual extension of C.The characteristic modules of A are constructed explicitly for a class of directed algebras,which generalizes the results of Xi.Furthermore,it is shown that the characteristic modules of dual extensions of a certain class of directed algebras admit the left Gr(?)bner basis theory in the sense of E.L.Green. 展开更多
关键词 Quasi-hereditary algebra Dual extension characteristic module (Left)Gr(?)bner basis
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Analysis of echo signal modulation characteristic parameters on aerial and space targets
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作者 Si Chen Hai-yang Zhang +3 位作者 Chang-ming Zhao Yu Fan Hong Chen Lin Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期146-154,共9页
Based on the scattering characteristic,the comparison of RCS(radar cross-section)at different positions of a target in the same direction of incidence can be obtained first by extruding or deleting part of the entity.... Based on the scattering characteristic,the comparison of RCS(radar cross-section)at different positions of a target in the same direction of incidence can be obtained first by extruding or deleting part of the entity.A simulation method of aerial&space targets echo characteristics(A&STEC)is proposed that is universal to aerial and space targets.We utilize a fixed-wing UAV(unmanned aerial vehicle)and typical missiles in simulation.The echo signal modulation characteristic parameters are calculated theoretically by the atmospheric attenuation model,the finite element method and a MUMPS solver.The verification simulations show that this method can analyze the influence of the target shape,incident direction,detection position and detection frequency on echo waveform,intensity and energy distribution.The results show that the profile of echo waveform can invert the general shape of the target.The relationship between time and intensity can determine whether the target is moving towards or away from the detector in addition.These conclusions can provide a reference for the ballistic missile target tracking and the defense against UVA intrusion in theory. 展开更多
关键词 Echo signal modulation characteristic parameters Simple targets The fixed-wing UVA Missiles Scattering characteristics
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Research progress of cholesteric liquid crystals with broadband reflection characteristics in application of intelligent optical modulation materials 被引量:1
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作者 张兰英 高延子 +9 位作者 宋平 武晓娟 苑晓 何宝凤 陈兴武 胡望 郭仁炜 丁杭军 肖久梅 杨槐 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期13-23,共11页
Cholesteric liquid crystals(CLCs) have recently sparked an enormous amount of interest in the development of soft matter materials due to their unique ability to self-organize into a helical supra-molecular architec... Cholesteric liquid crystals(CLCs) have recently sparked an enormous amount of interest in the development of soft matter materials due to their unique ability to self-organize into a helical supra-molecular architecture and their excellent selective reflection of light based on the Bragg relationship.Nowadays,by the virtue of building the self-organized nanostructures with pitch gradient or non-uniform pitch distribution,extensive work has already been performed to obtain CLC films with a broad reflection band.Based on authors' many years' research experience,this critical review systematically summarizes the physical and optical background of the CLCs with broadband reflection characteristics,methods to obtain broadband reflection of CLCs,as well as the application in the field of intelligent optical modulation materials.Combined with the research status and the advantages in the field,the important basic and applied scientific problems in the research direction are also introduced. 展开更多
关键词 cholesteric liquid crystals soft matter materials broadband reflection characteristics intelligent optical modulation materials
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Large Signal Modulation Characteristics in the Transition Regime for Two-State Lasing Quantum Dot Lasers
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作者 吕尊仁 季海铭 +4 位作者 杨晓光 罗帅 高凤 许锋 杨涛 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期63-67,共5页
Large-signal modulation capability, as an important performance indicator, is directly related to the high-speed optical communication technology involved. We experimentally and theoretically investigate the large-sig... Large-signal modulation capability, as an important performance indicator, is directly related to the high-speed optical communication technology involved. We experimentally and theoretically investigate the large-signal modulation characteristics of the simultaneous ground-state (GS) and the excited-state (ES) lasing in InAs/OaAs quantum dot laser diodes. The large-signal modulation capability of total light intensity in the transition regime from OS lasing to two-state lasing is unchanged as the bias-current increases. However, GS and ES large-signal eye diagrams show obvious variations during the transition. Relaxation oscillations and large-signal eye diagrams for OS, ES, and total light intensities are numerically simulated and analyzed in detail by using a rate-equation model. The -ndings show that a complementary relationship between the light intensities for OS and ES lasing exists in both the transition regime and the two-state lasing regime, leading to a much smaller overshooting power and a shorter settling time for the total light intensity. Therefore, the eye diagrams of GS or ES lasing are diffuse whereas those of total light intensity are constant as the bias-current increases in the transition regime. 展开更多
关键词 GS for Large Signal Modulation characteristics in the Transition Regime for Two-State Lasing Quantum Dot Lasers ES of in
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Damage Characteristics of the Logical Chip Module Due to Plasma Created by Hypervelocity Impacts
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作者 唐恩凌 吴尽 +9 位作者 王猛 张立佼 相升海 夏瑾 刘淑华 贺丽萍 韩雅菲 徐名扬 张爽 袁健飞 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第4期412-416,共5页
To researching the damage characteristics of typical logical chip modules in spacecraft due to plasma generated by hypervelocity impacts,we have established a triple Langmuir probe diagnostic system and a logical chip... To researching the damage characteristics of typical logical chip modules in spacecraft due to plasma generated by hypervelocity impacts,we have established a triple Langmuir probe diagnostic system and a logical chips measurement system,which were used to diagnose plasma characteristic parameters and the logical chip module's logical state changes due to the plasma created by a 7075 aluminum projectile hypervelocity impact on the 2A12 aluminum target.Three sets of experiments were performed with the collision speeds of 2.85 km/s,3.1 km/s and2.20 km/s,at the same incident angles of 30 degrees and logical chip module's positions by using a two-stage light gas gun loading system,a plasma characteristic parameters diagnostic system and a logical chip module's logical state measurement system,respectively.Electron temperature and density were measured at given position and azimuth,and damage estimation was performed for the logical chip module by using the data acquisition system.Experimental results showed that temporary damage could be induced on logical chip modules in spacecraft by plasma generated by hypervelocity impacts under the given experimental conditions and the sensors' position and azimuth. 展开更多
关键词 hypervelocity impact plasma logical chip module damage characteristics spacecraft
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A Construction of Characteristic Tilting Modules 被引量:2
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作者 DENG Bang Ming Department of Mathematics. Beijing Normal University. Beijing 100875. P. H. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第1期129-136,共8页
Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constru... Associated with each finite directed quiver Q is a quasi-hereditary algebra. the so-called twisted double of the path algebra kQ. Characteristic tilting modules over this class of quasi-hereditary algebras are constructed. Their endonorphism algebras are explicitly described. It turns out that this class of quasi-hereditary algebras is closed under taking the Ringel dual. 展开更多
关键词 Quasi-hereditary algebra characteristic tilting module Ringel dual
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Design of a Reflective Intensity Optical Fibre Bundle Displacement Sensor
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作者 Binghui Jia Jing Yu +2 位作者 Yong Feng Min Zhang Gang Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第4期84-96,共13页
Optical fibre sensor has the advantages of small size,light weight,anti⁃electromagnetic interference,and high measurement accuracy,which has important applications in research and industrial production.To design an op... Optical fibre sensor has the advantages of small size,light weight,anti⁃electromagnetic interference,and high measurement accuracy,which has important applications in research and industrial production.To design an optical fibre displacement sensor(OFBDS)with simple structure and high measurement accuracy,the unified model of the commonly used OFBDS structures was proposed and the feasibility of the intensity⁃modulation of multi⁃structural optical fibre bundles was analysed based on the arrangement characteristics of the fibre bundle end⁃face.The intensity⁃modulation characteristic of different fibre bundles was analysed,and the single coil coaxial fibre bundle was chosen as the fibre probe in this study.The sensor hardware system was designed.Lastly,the calibration experiment,temperature interference experiment,changes of measured plane surface area,and the dynamic experiment were conducted.Results showed that the sensor linear measurement range was about 3 mm,and the sensor system had excellent static and dynamic characteristics. 展开更多
关键词 optical fibre bundle displacement sensor intensity⁃modulation characteristic static experiment dynamic experiment
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