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On the Flatness and Injectivity of Dual Modules(II)
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作者 黄兆泳 唐金玉 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第3期377-383,共7页
For a commtative ring R and an injective cogenerator E in the category of R-modules, we characterize QF rings, IF rings and semihereditary rings by using the properties of the dual modules with respect to E.
关键词 QF rings FLATNESS INJECTIVITY dual modules.
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Dual pairs of tilting pairs
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作者 廖贻华 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期347-350,共4页
A module pair (C, T) over an Artin algebra A is called a tilting pair if both C and T are selforthogonal modules and the conditions T e ada C and C ∈ add T hold. The duality on a tilting pair is investigated to dis... A module pair (C, T) over an Artin algebra A is called a tilting pair if both C and T are selforthogonal modules and the conditions T e ada C and C ∈ add T hold. The duality on a tilting pair is investigated to discuss the condition under which the dual of a tilting pair is also a tilting pair. A necessary and sufficient condition of (D(7), D(C) ) being an n-tilting pair over an Artin algebra for an n-tilting pair ( C, 7) is given. And, a necessary and sufficient condition of ( T^*, C^* ) being an ntilting pair over a selfinjective Artin algebra for an n-tilting pair (C, 7) is also given. 展开更多
关键词 selforthogonal module selfinjective dual module tilting pair
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Electro-optical dual modulation on resistive switching behavior in BaTiO3/BiFeO3/TiO2 heterojunction 被引量:1
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作者 Jia-Jia Zhao Jin-Shuai Zhang +4 位作者 Feng Zhang Wei Wang Hai-Rong He Wang-Yang Cai Jin Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期292-297,共6页
The novel BaTiO3/BiFeO3/TiO2 multilayer heterojunction is prepared on a fluorine-doped tinoxide(FTO) substrate by the sol–gel method. The results indicate that the Pt/Ba TiO3/BiFeO3/TiO2/FTO heterojunction exhibits s... The novel BaTiO3/BiFeO3/TiO2 multilayer heterojunction is prepared on a fluorine-doped tinoxide(FTO) substrate by the sol–gel method. The results indicate that the Pt/Ba TiO3/BiFeO3/TiO2/FTO heterojunction exhibits stable bipolar resistive switching characteristic, good retention performance, and reversal characteristic. Under different pulse voltages and light fields, four stable resistance states can also be realized. The analysis shows that the main conduction mechanism of the resistive switching characteristic of the heterojunction is space charge limited current(SCLC) effect. After the comprehensive analysis of the band diagram and the P–E ferroelectric property of the multilayer heterojunction, we can deduce that the SCLC is formed by the effect of the oxygen vacancy which is controlled by ferroelectric polarizationmodulated change of interfacial barrier. And the effective photo-generated carrier also plays a regulatory role in resistance state(RS), which is formed by the double ferroelectric layer Ba TiO3/BiFeO3 under different light fields. This research is of potential application values for developing the multi-state non-volatile resistance random access memory(RRAM) devices based on ferroelectric materials. 展开更多
关键词 ferroelectric multilayer heterojunction resistive switching characteristic electro-optical dual modulation multi-state resistance
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Design of a Novel Dual Flux Modulation Machine with Consequent-Pole Spoke-Array Permanent Magnets in Both Stator and Rotor 被引量:4
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作者 Ziyi Liang Yuting Gao +1 位作者 Dawei Li Ronghai Qu 《CES Transactions on Electrical Machines and Systems》 2018年第1期73-81,共9页
In this paper,a novel dual flux modulation(DFM)machine with consequent-pole spoke-array permanent magnets(PMs)in both stator and rotor is proposed to achieve a larger torque density than regular flux modulation machin... In this paper,a novel dual flux modulation(DFM)machine with consequent-pole spoke-array permanent magnets(PMs)in both stator and rotor is proposed to achieve a larger torque density than regular flux modulation machines.The stator has two portions of PMs,one is set next to the stator slot with circumferential magnetization,and the other is inserted between the stator yoke and flux bridge with radial magnetization.The rotor has consequent-pole spoke-array PMs and alternative flux bridges.The proposed DFMPM machine can be regarded as the combination of the flux switching PM(FSPM)machine and vernier PM(VPM)machine.First,the structure and operational principle are introduced.Then,the proposed 12-stator-slot/10-rotor-tooth dual flux modulation permanent magnet(DFMPM)machine is compared with the FSPM machine and VPM machine in terms of flux lines distribution,back-electromotive force(EMF),cogging torque and average torque.Finally,the four proposed DFMPM machines are optimized for maximum average torque and minimum ripple torque considering the effects of split ratio,slot opening ratio,PM depth,PM angle and iron angle. 展开更多
关键词 dual flux modulation(DFM) flux bridges torque density flux switching(FS) vernier
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Characterizations of Graded Primitive Rings with Non-zero Graded Socles
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作者 王尧 任艳丽 《Northeastern Mathematical Journal》 CSCD 2003年第2期161-168,共8页
In this paper, we characterize the structure of group graded primitive rings having minimal graded one-sided ideals in terms of graded dual modules. We also show that two structure representations of this class of gra... In this paper, we characterize the structure of group graded primitive rings having minimal graded one-sided ideals in terms of graded dual modules. We also show that two structure representations of this class of graded primitive rings are both in a sense uniquely determined by the graded primitive rings considered. 展开更多
关键词 graded dual module graded dense ring graded semi-morphism
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Strongly lifting modules and strongly dual Rickart modules
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作者 Yongduo WANG 《Frontiers of Mathematics in China》 SCIE CSCD 2017年第1期219-229,共11页
The concepts of strongly lifting modules and strongly dual Rickart modules are introduced and their properties are studied and relations between them are given in this paper. It is shown that a strongly lifting module... The concepts of strongly lifting modules and strongly dual Rickart modules are introduced and their properties are studied and relations between them are given in this paper. It is shown that a strongly lifting module has the strongly summand sum property and the generalized Hopfian property, and a ring R is a strongly regular ring if and only if RR is a strongly dual Rickart module, if and only if aR is a fully invariant direct summand of RR for every a∈R. 展开更多
关键词 Lifting module strongly lifting module dual Rickart module strongly dual Rickart module
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Colorless WDM-PON Using Single Side Band Carrier Suppressed Signals Mitigating Carrier Rayleigh Backscattering
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作者 Rahat Ullah Bo Liu +9 位作者 Qi Zhang Yousaf Khan Amjad Ali Qinghua Tian Feng Tian M.Saad Khan Tabinda Salam Sibghat Ullah Lijia Zhang Xiangjun Xin 《China Communications》 SCIE CSCD 2016年第12期150-161,共12页
A new scheme is offered for minimizing carrier Rayleigh backscattering(CRB) in single feeder fiber based wavelength division multiplexed passive optical network(WDM-PON). The proposed scheme is based on single side ba... A new scheme is offered for minimizing carrier Rayleigh backscattering(CRB) in single feeder fiber based wavelength division multiplexed passive optical network(WDM-PON). The proposed scheme is based on single side band carrier suppressed(SSBCS) signal, both at network and receiver sides, used for the first time at optical line terminal(OLT) and optical network unit(ONU) sides. We use dual-drive Mach-zehnder modulator(DD-MZM) for generating SSB-CS signals, which decreases the expense per bit in full transmission. SSB-CS mitigates CRB, both at OLT and ONU sides, because of having no chance of reflections from the carrier. Since no extra dedicated RF or laser source is used at ONU side, we thus achieve cost effective colorless WDM-PON system. Suppressed signals from four channels, each of 10 Gbps, are multiplexed before injecting into the fiber span of 25 km at OLT. At ONU side, half of the downlink power is used for re-modulating the data signal. The simulation results show an errorfree transmission. Moreover, the detailed power budget calculations show that the proposed scheme can be sought out for splitting ratio up to 128. Hence it offers enough system's margin for unseen losses. 展开更多
关键词 Carrier Rayleigh backscattering dual drive Mach-zehnder modulator single side band suppress carrier on-off keying
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Model Predictive Torque Control for a Dual Three-phase PMSM Using Modified Dual Virtual Vector Modulation Method
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作者 Zhujin Ren Jinghua Ji +3 位作者 Hongyu Tang Tao Tao Linsen Huang Wenxiang Zhao 《Chinese Journal of Electrical Engineering》 CSCD 2022年第4期91-103,共13页
Single voltage vectors applied in the conventional model predictive torque control(MPTC)for multiphase motors do not only suffer from serious torque and stator flux ripples but also cause the large harmonic current.To... Single voltage vectors applied in the conventional model predictive torque control(MPTC)for multiphase motors do not only suffer from serious torque and stator flux ripples but also cause the large harmonic current.To address the aforementioned challenges,an MPTC using a modified dual virtual vector modulation method is proposed to improve the operational performance of a dual three-phase permanent magnet synchronous motor.Virtual voltage vectors are synthesized as the candidate control set to restrain the harmonic current.A transformation method is introduced to consider both the stator flux and torque in the duty cycle modulation.The torque and stator flux ripples are simultaneously reduced by addressing the limitations of nonuniform units.Furthermore,the null voltage vector is then inserted to expand the modulation range and improve the steady-state performance.Moreover,the sawtooth carrier is adopted to address the challenge of the asymmetric switch sequence caused by the modified modulation.Finally,the experimental results are presented to verify the effectiveness and superiority of the proposed MPTC method. 展开更多
关键词 Model predictive torque control dual three-phase motor permanent magnet synchronous motor dual virtual vector modulation
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Dual-function natural products:Farnesoid X receptor agonist/inflammation inhibitor for metabolic dysfunction-associated steatotic liver disease therapy
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作者 WANG Kang ZHANG Pengfei +9 位作者 SUN Huiyong CUI Shuang AO Lanjia CUI Ming XU Xiaowei WANG Lin XU Yuanyuan WANG Guangji WANG Hong HAO Haiping 《Chinese Journal of Natural Medicines》 SCIE CAS 2024年第11期965-976,共12页
Metabolic dysfunction-associated steatotic liver disease(MASLD)is the most prevalent chronic liver disease globally,with only one Food and Drug Administration(FDA)-approved drug for its treatment.Given MASLD's com... Metabolic dysfunction-associated steatotic liver disease(MASLD)is the most prevalent chronic liver disease globally,with only one Food and Drug Administration(FDA)-approved drug for its treatment.Given MASLD's complex pathophysiology,ther-apies that simultaneously target multiple pathways are highly desirable.One promising approach is dual-modulation of the famesoid X receptor(FXR),which regulates lipid and bile acid metabolism.However,FXR agonists alone are insufficient due to their limited anti-inflammatory effects.This study aimed to dto identify natural products capable of both FXR activation and inflammation inhibition to provide a comprehensive therapeutic approach for MASLD.Potential FXR ligands from the Natural Product Library were predicted via virtual screening using the Protein Preparation Wizard module in Schrodinger(2018)for molecular docking.Direct binding and regulation of candidate compounds on FXR were analyzed using surface plasmon resonance(SPR)binding assay,reporter gene ana-lysis,and reverse transcription-polymerase chain reaction(RT-PCR).The anti-inflammatory properties of these compounds were eval-uated in AML12 cells treated with tumor necrosis factor-alpha(TNF-α).Dual-function compounds with FXR agonism and inflamma-tion inhibition were further identified in cells transfected with Fxr siRNA and treated with TNF-α.The effects of these dual-function compounds on lipid accumulation and inflammation were evaluated in cells treated with palmitic acid.Results revealed that 17 natural products were predicted via computational molecular docking as potential FXR agonists,with 15 exhibiting a strong affinity for FXR recombinant protein.Nine isoflavone compounds significantly enhanced FXR reporter luciferase activity and the mRNA expressions of Shp and Ostb.Structure-activity relationship analysis indicated that introducing isopropyl or methoxy groups at the C7 position or a methoxy group at the C6 position could enhance the agonistic efficacy of isoflavones.Three compounds(2,6,and 8)were identified as dual-function natural products functioning as FXR agonists and inflammatory inhibitors,while one compound(12)acted as an FXR agonist to inhibit inflammation.These natural products protected hepatocytes against palmitic acid-induced lipid accumulation and in-flammation.In conclusion,compounds 2,6,and 8(genistein,biochanin A,and 7-methoxyisoflavone,respectively)were identified as dual-function bioactive products that transactivate FXR and inhibit inflammation,serving as potential candidates or lead compounds for MASLD therapy. 展开更多
关键词 FXR agonist Inflammation dual modulator Natural products MASLD
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