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Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN
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作者 Jiang Jie Lyu Bin +1 位作者 Chen Pengcheng Yang Zhen 《China Communications》 SCIE CSCD 2024年第6期23-39,共17页
In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both... In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the RS.We formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource allocation.To solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation techniques.Specifically,the tightness of applying the SDR is proved.Simulation results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively. 展开更多
关键词 active reconfigurable intelligent surface BEAMFORMING sum-rate maximization wireless powered communication network
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Information Technology in Domain of Electronic Intelligence and Cyberterrorism Combat
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作者 Robert Brumnik Sergii Kavun 《Computer Technology and Application》 2015年第1期45-56,共12页
Terms of intelligence in 20th and 21th century mean the methods of automatic extraction, analysis, interpretation and use of information. Thus, the intelligence services in the future created an electronic database in... Terms of intelligence in 20th and 21th century mean the methods of automatic extraction, analysis, interpretation and use of information. Thus, the intelligence services in the future created an electronic database in which to their being classified intelligence products, users could choose between the latter themselves relevant information. The EU (European Union) that activities are carried out from at least in year 1996, terrorist attacks in year 200l is only accelerating. Proposals to increase surveillance and international cooperation in this field have been drawn up before September 11 2011. On the Web you can fmd a list of networks (Cryptome, 2011), which could be connected, or are under the control of the security service--NSA (National Security Agency). United States of America in year 1994 enacted a law for telephone communication--Digital Telephony Act, which would require manufacturers of telecommunications equipment, leaving some security holes for control. In addition, we monitor the Internet and large corporations. The example of the United States of America in this action reveals the organization for electronic freedoms against a telecom company that the NSA illegally gains access to data on information technology users and Internet telephony. 展开更多
关键词 intelligence and counterintelligence activities electronic spy devices detection methods netwar counterterrorism.
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Electrospun gelatin/chitosan nanofibers containing curcumin for multifunctional food packaging 被引量:1
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作者 Mengxia Duan Jishuai Sun +4 位作者 Yequn Huang Haixin Jiang Yaqin Hu Jie Pang Chunhua Wu 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期614-621,共8页
Recently,food grade nanofiber-based materials have received growing attentions in food packaging.In this work,novel active and intelligent packaging nanofibers based on gelatin/chitosan with curcumin(GA/CS/CUR)were de... Recently,food grade nanofiber-based materials have received growing attentions in food packaging.In this work,novel active and intelligent packaging nanofibers based on gelatin/chitosan with curcumin(GA/CS/CUR)were developed via electrospinning technique.Effects of the incorporation of CUR content(0.1%-0.3%,m/m)on the microstructure and functional properties of the electrospun nanofibers were investigated.Morphological studies using scanning electron microscopy indicated that loading CUR can affect the average diameter of nanofiber mats,which remained around 160-180 nm.The addition of an appropriate level CUR(0.2%,m/m)led to a stronger intermolecular interaction,and thus enhanced the thermal stability and tensile strength of the obtained nanofibers.Meanwhile,the incorporation of CUR significantly improved antioxidant activity and the antimicrobial activity of GA/CS/CUR nanofibers.Moreover,the sensitivity of nanofibers to ammonia results indicated that GA/CS nanofibers containing 0.2%CUR(GA/CS/CURⅡ)presented high sensitivity of colorimetric behavior to ammonia(within 3 min).These results suggest GA/CS/CURⅡnanofibers has great potential as a multifunctional packaging to protect and monitor the freshness of proteinrich animal foods,such as meat and seafood. 展开更多
关键词 Electrospun nanofibers CURCUMIN NH3 indicator Active and intelligent packaging Antibacterial and antioxidant activities
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Outage Behaviors of Active Intelligent Reflecting Surface Enabled NOMA Communications
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作者 Zhiping Lu Xinwei Yue +1 位作者 Shuo Chen Weiguo Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期789-812,共24页
Active intelligent reflecting surface(IRS)is a novel and promising technology that is able to overcome the multiplicative fading introduced by passive IRS.In this paper,we consider the application of active IRS to non... Active intelligent reflecting surface(IRS)is a novel and promising technology that is able to overcome the multiplicative fading introduced by passive IRS.In this paper,we consider the application of active IRS to nonorthogonalmultiple access(NOMA)networks,where the incident signals are amplified actively through integrating amplifier to reflecting elements.More specifically,the performance of active/passive IRS-NOMA networks is investigated over large and small-scale fading channels.Aiming to characterize the performance of active IRSNOMA networks,the exact and asymptotic expressions of outage probability for a couple of users,i.e.,near-end user n and far-end user m are derived by exploiting a 1-bit coding scheme.Based on approximated analyses,the diversity orders of user n and user m are obtained for active IRS-NOMA.In addition,the system throughput of active IRS-NOMA is discussed in the delay-sensitive transmission.The simulation results are carried out to verify that:i)The outage behaviors of active IRS-NOMAnetworks are superior to that of passive IRS-NOMAnetworks;ii)As the reflection amplitude factors increase,the active IRS-NOMAnetworks are capable of furnishing the enhanced outage performance;and iii)The active IRS-NOMA has a larger system throughput than passive IRS-NOMA and conventional communications. 展开更多
关键词 Active intelligent reflecting surface amplification noise non-orthogonal multiple access outage probability
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Anthocyanins/chitosan films doped by nano zinc oxide for active and intelligent packaging:comparison of anthocyanins source from purple tomato or black wolfberry
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作者 Yana Li Zenghui Li +2 位作者 Yuwen Wang Liangbo Sun Houchang Pei 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2023年第6期704-715,共12页
The multifunctional films was prepared by blending chitosan and nano-ZnO with purple tomato anthocyanins or black wolfberry anthocyanins.The properties of films functioned by anthocyanins source and nano-ZnO content w... The multifunctional films was prepared by blending chitosan and nano-ZnO with purple tomato anthocyanins or black wolfberry anthocyanins.The properties of films functioned by anthocyanins source and nano-ZnO content were studied.It was found purple tomato anthocyanins showed more significant color change against pH than black wolfberry anthocyanins.The nano-ZnO were widely dispersed in matrix and enhanced the compatibility of anthocyanins with chitosan.However,the anthocyanins source influenced the properties of the films more slightly than nano-ZnO addition.The tensile strength,antioxidant and antibacterial effects of the chitosan films dramatically increased after cooperated by nano-ZnO and anthocyanins,which also enhanced with increase of nano-ZnO content,whereas the elongation at break of the composite films decreased.Especially,the anthocyanin and nano-ZnO promoted the antibacterial activity of films synergistically.Composite films made from black wolfberry anthocyanins exhibited higher mechanical performance than those made from purple tomato anthocyanins but weaker antibacterial effects.The purple tomato anthocyanins/chitosan and nano-ZnO/purple tomato anthocyanins/chitosan films effectively reflected pork spoilage,changing their colors from dark green to brown,indicating the potential for applications in active and intelligent food packaging. 展开更多
关键词 bio-based multifunction colorimetric indicator active and intelligent packaging
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