Intelligent edge computing carries out edge devices of the Internet of things(Io T) for data collection, calculation and intelligent analysis, so as to proceed data analysis nearby and make feedback timely. Because of...Intelligent edge computing carries out edge devices of the Internet of things(Io T) for data collection, calculation and intelligent analysis, so as to proceed data analysis nearby and make feedback timely. Because of the mobility of mobile equipments(MEs), if MEs move among the reach of the small cell networks(SCNs), the offloaded tasks cannot be returned to MEs successfully. As a result, migration incurs additional costs. In this paper, joint task offloading and migration schemes in mobility-aware Mobile Edge Computing(MEC) network based on Reinforcement Learning(RL) are proposed to obtain the maximum system revenue. Firstly, the joint optimization problems of maximizing the total revenue of MEs are put forward, in view of the mobility-aware MEs. Secondly, considering time-varying computation tasks and resource conditions, the mixed integer non-linear programming(MINLP) problem is described as a Markov Decision Process(MDP). Then we propose a novel reinforcement learning-based optimization framework to work out the problem, instead traditional methods. Finally, it is shown that the proposed schemes can obviously raise the total revenue of MEs by giving simulation results.展开更多
Road silt loading(sL)is an important parameter in the fugitive road dust(FRD)emissions.In this study,the improved Testing Re-entrained Aerosol Kinetic Emissions from Roads(TRAKER)combined with the AP-42 method was fir...Road silt loading(sL)is an important parameter in the fugitive road dust(FRD)emissions.In this study,the improved Testing Re-entrained Aerosol Kinetic Emissions from Roads(TRAKER)combined with the AP-42 method was firstly developed to quickly measure and estimate the sLs of paved roads in Beijing,China.The annual average sLs in Beijing was 0.59±0.31 g/m^(2)in 2020,and decreased by 22.4%compared with that in 2019.The seasonal variations of sLs followed the order of spring>winter>summer>autumn in the two years.The seasonal mean road sLs on the same type road in the four seasons presented a decline trend from^(2)019 to 2020,especially on the Expressway,decreasing 47.4%-72.7%.The road sLs on the different type roads in the same season followed the order of Major arterial∼Minor arterial∼Branch road>Express road,and Township road∼Country highway>Provincial highway∼National highway.The emission intensities of PM10 and PM_(2.5)from FRD in Beijing in 2020 were lower than those in 2019.The PM10 and PM_(2.5)emission intensities at the four planning areas in the two years all presented the order of the capital functional core area>the urban functional expansion area>the urban development new area>the ecological conservation and development area.The annual emissions of PM10 and PM_(2.5)from FRD in Beijing in 2020 were 74,886 ton and 18,118 ton,respectively,decreasing by∼33.3%compared with those in 2019.展开更多
Chikungunya virus(CHIKV)is a re-emerging mosquito-transmitted RNA virus causing joint and muscle pain.To better understand how CHIKV rewires the host cell and usurps host cell functions,we generated a systematic CHIKV...Chikungunya virus(CHIKV)is a re-emerging mosquito-transmitted RNA virus causing joint and muscle pain.To better understand how CHIKV rewires the host cell and usurps host cell functions,we generated a systematic CHIKV-human protein-protein interaction map and revealed several novel connections that will inform further mechanistic studies.One of these novel interactions,between the viral protein E1 and STIP1 homology and U-box containing protein 1(STUB1),was found to mediate ubiquitination of E1 and degrade E1 through the proteasome.Capsid associated with G3BP1,G3BP2 and AAAþATPase valosin-containing protein(VCP).Furthermore,VCP inhibitors blocked CHIKV infection,suggesting VCP could serve as a therapeutic target.Further work is required to fully understand the functional consequences of these interactions.Given that CHIKV proteins are conserved across alphaviruses,many virus-host protein-protein interactions identified in this study might also exist in other alphaviruses.Construction of interactome of CHIKV provides the basis for further studying the function of alphavirus biology.展开更多
Reflectors are an essential component for on-chip integrated photonics. Here, we propose a new method for designing reflectors on the prevalent thin-film-on-insulator platform by using genetic-algorithm optimization.I...Reflectors are an essential component for on-chip integrated photonics. Here, we propose a new method for designing reflectors on the prevalent thin-film-on-insulator platform by using genetic-algorithm optimization.In simulation, the designed reflector with a footprint of only 2.16 μm× 2.16 μm can achieve ~97% reflectivity and 1 dB bandwidth as wide as 220 nm. The structure is composed of randomly distributed pixels and is highly robust against the inevitable corner rounding effect in device fabrication. In experiment, we fabricated on-chip Fabry–Perot(FP) cavities constructed from optimized reflectors. Those FP cavities have intrinsic quality factors of>2000 with the highest value beyond 4000 in a spectral width of 200 nm. The reflectivity fitted from the FP cavity resonances is >85% in the entire wavelength range of 1440–1640 nm and is beyond 95% at some wavelengths.The fabrication processes are CMOS compatible and require only one step of lithography and etch. The devices can be used as a standard module in integrated photonic circuitry for wide applications in on-chip semiconductorlaser structures and optical signal processing.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 61701038。
文摘Intelligent edge computing carries out edge devices of the Internet of things(Io T) for data collection, calculation and intelligent analysis, so as to proceed data analysis nearby and make feedback timely. Because of the mobility of mobile equipments(MEs), if MEs move among the reach of the small cell networks(SCNs), the offloaded tasks cannot be returned to MEs successfully. As a result, migration incurs additional costs. In this paper, joint task offloading and migration schemes in mobility-aware Mobile Edge Computing(MEC) network based on Reinforcement Learning(RL) are proposed to obtain the maximum system revenue. Firstly, the joint optimization problems of maximizing the total revenue of MEs are put forward, in view of the mobility-aware MEs. Secondly, considering time-varying computation tasks and resource conditions, the mixed integer non-linear programming(MINLP) problem is described as a Markov Decision Process(MDP). Then we propose a novel reinforcement learning-based optimization framework to work out the problem, instead traditional methods. Finally, it is shown that the proposed schemes can obviously raise the total revenue of MEs by giving simulation results.
基金This research was funded by the Development and Demonstration of Road Dust Monitoring and Management System(No.Z191100009119011)the National Research Program for Key Issues in Air Pollution Control China(No.DQGG0201)the National Key Research and Development program of China(No.2018YFC0213203).
文摘Road silt loading(sL)is an important parameter in the fugitive road dust(FRD)emissions.In this study,the improved Testing Re-entrained Aerosol Kinetic Emissions from Roads(TRAKER)combined with the AP-42 method was firstly developed to quickly measure and estimate the sLs of paved roads in Beijing,China.The annual average sLs in Beijing was 0.59±0.31 g/m^(2)in 2020,and decreased by 22.4%compared with that in 2019.The seasonal variations of sLs followed the order of spring>winter>summer>autumn in the two years.The seasonal mean road sLs on the same type road in the four seasons presented a decline trend from^(2)019 to 2020,especially on the Expressway,decreasing 47.4%-72.7%.The road sLs on the different type roads in the same season followed the order of Major arterial∼Minor arterial∼Branch road>Express road,and Township road∼Country highway>Provincial highway∼National highway.The emission intensities of PM10 and PM_(2.5)from FRD in Beijing in 2020 were lower than those in 2019.The PM10 and PM_(2.5)emission intensities at the four planning areas in the two years all presented the order of the capital functional core area>the urban functional expansion area>the urban development new area>the ecological conservation and development area.The annual emissions of PM10 and PM_(2.5)from FRD in Beijing in 2020 were 74,886 ton and 18,118 ton,respectively,decreasing by∼33.3%compared with those in 2019.
基金supported by National Natural Science Foundation of China (82072270 and 82272306)Taishan Scholars Program (tstp20221142)+1 种基金Shandong Provincial Natural Science Foundation (ZR2021QC095)Academic Promotion Programme of Shandong First Medical University (2019LJ001).
文摘Chikungunya virus(CHIKV)is a re-emerging mosquito-transmitted RNA virus causing joint and muscle pain.To better understand how CHIKV rewires the host cell and usurps host cell functions,we generated a systematic CHIKV-human protein-protein interaction map and revealed several novel connections that will inform further mechanistic studies.One of these novel interactions,between the viral protein E1 and STIP1 homology and U-box containing protein 1(STUB1),was found to mediate ubiquitination of E1 and degrade E1 through the proteasome.Capsid associated with G3BP1,G3BP2 and AAAþATPase valosin-containing protein(VCP).Furthermore,VCP inhibitors blocked CHIKV infection,suggesting VCP could serve as a therapeutic target.Further work is required to fully understand the functional consequences of these interactions.Given that CHIKV proteins are conserved across alphaviruses,many virus-host protein-protein interactions identified in this study might also exist in other alphaviruses.Construction of interactome of CHIKV provides the basis for further studying the function of alphavirus biology.
基金Hong Kong Research Grants Council Early Career Scheme(24208915)Hong Kong Research Grants Council Joint Research Scheme(N_CUHK415/15)National Natural Science Foundation of China(NSFC)
文摘Reflectors are an essential component for on-chip integrated photonics. Here, we propose a new method for designing reflectors on the prevalent thin-film-on-insulator platform by using genetic-algorithm optimization.In simulation, the designed reflector with a footprint of only 2.16 μm× 2.16 μm can achieve ~97% reflectivity and 1 dB bandwidth as wide as 220 nm. The structure is composed of randomly distributed pixels and is highly robust against the inevitable corner rounding effect in device fabrication. In experiment, we fabricated on-chip Fabry–Perot(FP) cavities constructed from optimized reflectors. Those FP cavities have intrinsic quality factors of>2000 with the highest value beyond 4000 in a spectral width of 200 nm. The reflectivity fitted from the FP cavity resonances is >85% in the entire wavelength range of 1440–1640 nm and is beyond 95% at some wavelengths.The fabrication processes are CMOS compatible and require only one step of lithography and etch. The devices can be used as a standard module in integrated photonic circuitry for wide applications in on-chip semiconductorlaser structures and optical signal processing.
