检索结果-南通市图书馆

Research on Global Clock Synchronization Mechanism in Software-Defined Control Architecture

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2022年第5期31卷 915-929页

作者： LYU Shuyu DAI Xinfa MA Zhong GAO Yi HU zhekun Harbin Engineering University Wuhan Digital Engineering Institute

Adopt software-definition technology to decouple the functional components of the industrial control system(ICS) in a service-oriented and distributed form is an important way for the industrial Internet of things to integrate information technology, communication technology, and operation technology. Therefore, this paper presents the concept of software-defined control architecture and describes the time consistency requirements under the paradigm shift of ICS architecture. By analyzing the physical clock and virtual clock mechanism models, the global clock synchronization space is logically divided into the physical and virtual clock synchronization domains, and a formal description of the global clock synchronization space is proposed. According to the fundamental analysis of the clock state model, the physical clock linear filtering synchronization model is derived, and a distributed observation fusion filtering model is constructed by considering the two observation modes of the virtual clock to realize the time synchronization of the global clock space by way of timestamp layer-by-layer transfer and fusion estimation. Finally, the simulation results show that the proposed model can significantly improve the accuracy and stability of clock synchronization.

关键词： software-defined control architecture communication technology clock state model information technology global clock synchronization mechanism synchronisation global clock space global clock synchronization space distributed observation fusion filtering model adopt software-definition technology time synchronization industrial control operation technology industrial control system synchronization model virtual clock mechanism models physical clock clocks filtering theory ICS architecture

Effect of carbon material and surfactant on ink property and resulting surface cracks of fuel-cell microporous layers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第5期69卷 1-12页

作者： zhekun Chen Weitong Pan Longfei Tang Xueli Chen Fuchen Wang Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is to evaluate the homogeneity of MPL with cracks quantitatively. This paper proposes the homogeneity index of a full-scale MPL with an area of 50 cm~2, which is yet to be reported in the literature to our knowledge. Besides, the effects of the carbon material and surfactant on the ink and resulting MPL structure have been studied. The ink with a high network development degree produces an MPL with low crack density, but the ink with high PDI produces an MPL with low crack homogeneity. The polarity of the surfactant and the non-polarity of polytetrafluoroethylene(PTFE) are not mutually soluble,resulting in the heterogeneous PTFE distribution. The findings of this study provide guidelines for MPL fabrication.

关键词： Proton-exchange-membrane fuel cell Microporous layer Crack density Crack homogeneity Polytetrafluoroethylene distribution Surfactant

High oxygen fugacity magma:implication for the destruction of the North China Craton

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2020年第2期39卷 161-171页

作者： zhekun Zhang Mingxing Ling Lipeng Zhang Saijun Sun Weidong Sun CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China State Key Laboratory of Isotope Geochemistry.Guangzhou Institute of Geochemistry Chinese Academy of Sciences.Guangzhou 510640China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100094China

The mechanism of lithospheric removal and destruction of the North China Craton(NCC)has been hotly debated for *** is now generally accepted that the subduction of the(Paleo)-Pacific plate played an important role in this ***,how the plate subduction contributed to the craton destruction remains *** we report high oxygen fugacity(fO2)characteristics of the Yunmengshan granite,e.g.,hematitemagnetite intergrowth supported by zircon Ce^4+/Ce^3+ratios and apatite Mn oxygen fugacity *** fO2 magmas are widely discovered in Late Mesozoic(160-130 Ma)adakitic rocks in central *** origin of high fO2 magma is likely related to the input of the"oxidized mantle components",which shows a dose connection between plate subduction and destruction of the *** research area is^1500 km away from the current Pacific subduction *** the back-arc extension of Japan Sea since the Cretaceous,this distance may be shortened to^800 km,which is still too far for normal plate *** subduction is the best candidate that was responsible for the large scale magmatism and the destruction of the *** slab-derived fluids and/or melts were liberated into an overlying mantle wedge and modified the lithospheric *** of the subducting plate induced the large-scale upwelling of asthenospheric mantle and triggered the formation of extensive high fO2 intraplate magmas.

关键词： High oxygen fugacity Decratonization North China Craton Plate subduction

All-optical vector visual cryptography with high security and rapid decryption

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Advances 2023年第5期6卷 1-3页

作者： zhekun Chen Minghui Hong Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Meta optics-empowered vector visual cryptography at the abundant degrees of freedom of light and spatial dislocation can open an avenue for optical information security and anti-counterfeiting with a compact footprint... 详细信息

关键词： visual optical optics

Wireless electrical stimulation at the nanoscale interface induces tumor vascular normalization

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2022年第12期7卷 399-408页

作者： Changhao Li Cairong Xiao Lizhen Zhan zhekun Zhang Jun Xing Jinxia Zhai Zhengnan zhou Guoxin Tan Jinhua Piao Yahong zhou Suijian Qi Zhengao Wang Peng Yu Chengyun Ning School of Material Science and Engineering National Engineering Research Center for Tissue Restoration and ReconstructionMetallic Materials Surface Functionalization Engineering Research Center of Guangdong ProvinceSouth China University of TechnologyGuangzhou510641China School of Food Science and Engineering South China University of TechnologyGuangzhou510641China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of ScienceBeijing100190China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China China-Singapore International Joint Research Institute Guangzhou511365China

Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.

关键词： Calcium distribution Mechano-electrical conversion Piezoelectric barium titanate Tumor vascular normalization Wireless electrical stimulation

Monolayer molecular crystals for low-energy consumption optical synaptic transistors

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2022年第8期15卷 7639-7645页

作者： zhekun Hua Ben Yang Junyao Zhang Dandan Hao Pu Guo Jie Liu Lang Jiang Jia Huang Interdisciplinary Materials Research Center School of Materials Science and EngineeringFrontiers Science Center for Intelligent Autonomous SystemsTongji UniversityShanghai 201804China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Translational Research Institute of Brain and Brain-Like Intelligence Shanghai Fourth People's Hospital Affiliated to Tongji UniversitySchool of Materials Science and EngineeringTongji UniversityShanghai 200434China

Artificial synaptic devices hold great potential in building neuromorphic *** to the unique morphological features,twodimensional organic semiconductors at the monolayer limit show interesting properties when acting as the active layers for organic field-effect ***,organic synaptic transistors are prepared with 1,4-bis((5’-hexyl-2,2’-bithiophen-5-yl)ethyl)benzene(HTEB)monolayer molecular *** similar to biological synapses,including excitatory postsynaptic current(EPSC),pair-pulse facilitation,and short/long-term memory,have been *** synaptic device achieves the minimum power consumption of 4.29 fJ at low drain voltage of−0.01 ***,the HTEB synaptic device exhibits excellent long-term memory with 109 s EPSC estimated retention ***-like functions such as dynamic learning-forgetting process and visual noise reduction are demonstrated by nine *** unique morphological features of the monolayer molecular semiconductors help to reveal the device working mechanism,and the synaptic behaviors of the devices can be attributed to oxygen induced energy *** work shows the potential of artificial neuroelectronic devices based on organic monolayer molecular crystals.

关键词： monolayer molecular crystals synaptic devices organic field-effect transistors optical synaptic transistors

Development of CMAQ for East Asia CO_2 data assimilation under an EnKF framework: a first result

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2014年第25期59卷 3200-3208页

作者： zhekun Huang Zhen Peng Hongnian Liu Meigen Zhang Xiaoguang Ma Shu-Chih Yang Sang-Deok Lee Seung-Yeon Kim School of Atmospheric Sciences Nanjing University State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences RIKEN Advanced Institute for Computational Science Kobe 650-0047 Japan National Institute of Environmental Research Incheon 404-708Republic of Korea

Under an Ensemble Kalman Filter(EnKF)framework,Regional Atmospheric Modeling System and Models-3 Community Multi-scale Air Quality(RAMS–CMAQ)modeling system is developed to be a CO2data assimilation system EnKF–CMAQ,and the EnKF–CMAQ system is then applied to East Asia for validation with real continuous surface CO2concentration observations available in the study domain instead of using an observation simulation system *** with an experimental period of January 23 to February 7,2007 are conducted,and the experimental results of the EnKF–CMAQ system and the RAMS–CMAQ model are compared against continuous surface CO2observations from assimilation sites and independent reference *** of daily mean CO2concentration increments show that the EnKF–CMAQ system confines the update of daily mean CO2within areas nearby and downwind of the assimilation *** the CO2concentration ensemble spreads and background error covariances show flow-dependent *** results indicate the crucial role of wind transport in the CO2data assimilation,which agrees with the previous *** average bias and the average root-mean-square error(RMSE)of daily mean CO2concentration at the assimilation sites are reduced by 1.00 and1.83 ppm,respectively,and those at the reference sites are reduced by 0.24 and 0.22 ppm,*** results demonstrate the EnKF–CMAQ system is capable of assimilating the continuous surface CO2concentration observations to improve the simulation accuracy of the atmospheric CO2synoptic *** growing CO2observations over East Asia are being available nowadays,this work is our first step to generate consistent spatial and temporal atmospheric CO2concentration fields over East Asia,particularly over China,using both in situ and satellite observations.

关键词：大气CO2浓度卡尔曼滤波数据同化集合区域大气模拟系统东亚框架开发

Fossil nothofagaceous leaves from the Eocene of western Antarctica and their bearing on the origin, dispersal and systematics of Nothofagus

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2007年第10期50卷 1525-1535页

作者： LI HaoMin1 & zhou zhekun2? 1 State Key Laboratory of Palaeobiology & Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sci- ences, Nanjing 210008, China 2 Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China State Key Laboratory of Palaeobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming China

Fossil leaves resembling Nothofagaceae have been investigated from the Eocene of western Antarctica and a new form genus Nothofagofolia is proposed for these kinds of fossils. Some new specimens belonging to this form genus are described. They were collected from the Fossil Hill locality of Fildes Peninsula, King George Island, South Shetland Islands, western Antarctica. Two new species, two new combinations and an unnamed species are reported. A number of published Nothofagus leaf fossils from the same locality are discussed and revised. As a result of these studies of Nothofagus leaf morphology, we conclude that (1) Nothofagus probably originated in high latitudes of the Southern Hemisphere during the middle-late Late Cretaceous and diversified, dispersed gradually to the lower latitudes of the same hemisphere; (2) leaf morphological characters are significant for the systematics of the family Nothofagaceae, especially at the intrageneric level; and (3) extant species of Nothofagus known from southern temperate areas have more primitive leaf morphological characters and lower leaf ranks than those from tropical mountains as well as those of the Fagaceae and Betulaceae.

关键词： Antarctica, Nothofagus, leaf morphology, leaf impression fossils, Gondwanaland, Nothofagofolia gen. et sp. nov., Eocene

在线全文

学校读者我要写书评

暂无评论

基于层次化片上网络的混合多播路由算法

哈尔滨工程大学学报 2013年第10期34卷 1327-1333页

作者：胡哲琨陈杰中国科学院微电子研究所北京100029

为了降低多播通信延时,提出了一种基于层次化二维mesh片上网络的混合多播(HM)路由算法,并给出了其死锁避免方案.该算法以3×3的子mesh为单位将二维mesh网络划分为若干个多播区域,每个区域的中间路由器都通过一个额外端口与上层mesh网络... 详细信息

为了降低多播通信延时,提出了一种基于层次化二维mesh片上网络的混合多播(HM)路由算法,并给出了其死锁避免方案.该算法以3×3的子mesh为单位将二维mesh网络划分为若干个多播区域,每个区域的中间路由器都通过一个额外端口与上层mesh网络的路由器相连.多播数据包在上层网络中按照Column-Path算法进行基于路径的多播,而在多播区域内则按照XY路由算法进行基于树的多播.仿真结果表明,相对于传统的基于路径的多播算法及基于树的RPM算法,HM算法能提供更小的多播延时,因此更适用于多目的通信的场合.

关键词：层次化片上网络多播路由死锁避免虫孔交换