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An integrated model to simulate sown area changes for major crops at a global scale

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science China Earth sciences 2008年第3期51卷 370-379页

作者： SHIBASAKI Ryosuke Center for Spatial information science University of Tokyo

Dynamics of land use systems have attracted much attention from scientists around the world due to their ecological and socio-economic implications. An integrated model to dynamically simulate future changes in sown areas of four major crops (rice, maize, wheat and soybean) on a global scale is pre- sented. To do so, a crop choice model was developed on the basis of Multinomial Logit (Logit) model to model land users' decisions on crop choices among a set of available alternatives with using a crop utility function. A GIS-based Environmental Policy Integrated Climate (EPIC) model was adopted to simulate the crop yields under a given geophysical environment and farming management conditions, while the International Food Policy and Agricultural Simulation (IFPSIM) model was utilized to estimate crop price in the international market. The crop choice model was linked with the GIS-based EPIC model and the IFPSIM model through data exchange. This integrated model was then validated against the FAO statistical data in 2001-2003 and the Moderate Resolution Imaging Spectroradiometer (MODIS) global land cover product in 2001. Both validation approaches indicated reliability of the model for ad- dressing the dynamics in agricultural land use and its capability for long-term scenario analysis. Finally, the model application was designed to run over a time period of 30 a, taking the year 2000 as baseline. The model outcomes can help understand and explain the causes, locations and consequences of land use changes, and provide support for land use planning and policy making.

关键词： land use change crop sown area simulation crop choice global scale

Dynamic Spectrum Access Based on Prior Knowledge Enabled Reinforcement Learning with Double Actions in Complex Electromagnetic Environment

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China Communications 2022年第7期19卷 13-24页

作者： Linghui Zeng Fuqiang Yao Jianzhao Zhang Min Jia The Sixty-third research institute National University of Defense TechnologyNanjing 210007China Communication research Center School of Electronics and Information EngineeringHarbin Institute of TechnologyHarbin 150080China

The spectrum access problem of cognitive users in the fast-changing dynamic interference spectrum environment is addressed in this *** prior knowledge for the dynamic spectrum access is modeled and a reliability quantification scheme is presented to guide the use of the prior knowledge in the learning ***,a spectrum access scheme based on the prior knowledge enabled RL(PKRL)is designed,which effectively improved the learning efficiency and provided a solution for users to better adapt to the fast-changing and high-density electromagnetic *** with the existing methods,the proposed algorithm can adjust the access channel online according to historical information and improve the efficiency of the algorithm to obtain the optimal access *** results show that,the convergence speed of the learning is improved by about 66%with the invariant average throughput.

关键词： prior knowledge reinforcement learning anti-jamming communication spectrum access

β-adrenoreceptor-triggered PKA activation negatively regulates the innate antiviral response

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Cellular & Molecular Immunology 2023年第2期20卷 175-188页

作者： Yi Guo Xia-Nan Zhang Shan Su Zi-Lun Ruan Ming-Ming Hu Hong-Bing Shu Department of Infectious Diseases Frontier Science Center for Immunology and MetabolismMedical Research InstituteZhongnan Hospital of Wuhan UniversityWuhan UniversityCollege of Life SciencesTaikang Center for Life and Medical SciencesWuhan UniversityResearch Unit of Innate Immune and Inflammatory DiseasesChinese Academy of Medical SciencesWuhanChina

Upon viral infection, cytoplasmic pattern recognition receptors detect viral nucleic acids and activate the adaptor protein VISA/MAVS- or MITA/STING-mediated innate antiviral response. Whether and how the innate antiviral response is regulated by neuronal endocrine functions is unclear. Here, we show that viral infection reduced the serum levels of the β-adrenergic hormones epinephrine and norepinephrine as well as the cellular levels of their receptors ADRB1 and ADRB2. We further show that an increase in epinephrine/norepinephrine level inhibited the innate antiviral response in an ADRB1-/2-dependent manner. Mechanistically, epinephrine/norepinephrine stimulation activated the downstream kinase PKA, which catalyzed the phosphorylation of MITA at S241, S243 and T263, inhibiting MITA activation and suppressing the innate immune response to DNA virus. In addition, phosphorylation of VISA at T54 by PKA antagonized the innate immune response to RNA virus. These findings reveal the regulatory mechanisms of innate antiviral responses by epinephrine/norepinephrine and provide a possible explanation for increased host susceptibility to viral infection in stressful and anxiety-promoting situations.

关键词： beta-adrenoreceptor PKA innate immunity virus signal transduction

A Model Predictive Control Algorithm Based on Biological Regulatory Mechanism and Operational research

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自动化学报:英文版 2023年第11期10卷 2174-2176页

作者： Jinying Yang Yongjun Zhang Tanju Yildirim Jiawei Zhang institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China National institute for Materials science Ibaraki 305-0047Japan School of Electrical and information Engineering University of SydneySydney 2000Australia

Dear Editor,This letter presents an intelligent model predictive control algorithm inspired by biological regulatory mechanism and operational research. In terms of overall architecture, based on biological regulatory system and operational research theory, priority factor module and central coordination module are innovatively added on the basis structure of heuristic dynamic programming to carry out overall regulation of the system.

关键词： carry letter programming

Data Security and Privacy in Bitcoin System:A Survey

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Journal of Computer science & Technology 2020年第4期35卷 843-862页

作者： Lie-Huang Zhu Bao-Kun Zheng Meng Shen Feng Gao Hong-Yu Li Ke-Xin Shi School of Computer science and Technology Beijing Institute of TechnologyBeijing 100081China School of information Management for Law China University of Political Science and LawBeijing 102249China Key Laboratory of information Network Security Ministry of Public SecurityShanghai 201204China

To date,bitcoin has been the most successful application of blockchain technology and has received considerable attention from both industry and *** is an electronic payment system based on cryptography rather than on *** of whether people are in the same city or country,bitcoin can be sent by any one person to any other person when they reach an *** market value of bitcoin has been rising since its advent in 2009,and its current market value is US160 *** its development,bitcoin itself has exposed many problems and is facing challenges from all the sectors of society;therefore,adversaries may use bitcoin's weakness to make considerable *** survey presents an overview and detailed investigation of data security and privacy in bitcoin *** examine the studies in the literature/Web in two categories:1)analyses of the attacks to the privacy,availability,and consistency of bitcoin data and 2)summaries of the countermeasures for bitcoin data *** on the literature/Web,we list and describe the research methods and results for the two *** compare the performance of these methods and illustrate the relationship between the performance and the ***,we present several important open research directions to identify the follow-up studies in this area.

关键词： security privacy bitcoin availability consistency

High Precision Mix-Signal Capacitor Mismatch Error Calibration Method for Charge-Domain Pipelined ADC

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Chinese Journal of Electronics 2019年第2期28卷 223-228页

作者： YU Zongguang ZOU Jiaxuan CHEN Zhenhai WEI Jinghe SU Xiaobo ZHANG Hong School of Microelectronic Xidian University No.58 research institute China Electronic Technology Group Corporation School of information Engineering Huangshan University School of Electronics and information Engineering Xi'an Jiaotong University

A mix-signal high precision capacitor mismatch error calibration method for charge domain pipelined ADCs is proposed. The calibration method calibrates the capacitors one by one based on binary *** errors caused by the capacitor mismatch in and between pipelined sub-stage circuits can be compensated by the proposed calibration method. Based on the proposed calibration method, a 14 bit 250 MS/s charge domain pipelined Analog-to-digital converter（ADC） is designed and realized in a 1P6M 0.18 m CMOS *** results show the 14 bit 250 MS/s ADC achieves the signal-to-noise ratio of 70.7 dBFS and the spurious free dynamic range of 84.6 dB, with 70.1 MHz single-tone sine wave input at 250 MS/s, while the ADC core consumes the power consumption of 235 mW and occupies an area of 3.2 mm;.

关键词： Pipelined analog-to-digital converter Charge domain(CD) For-ground calibration Low power Capacitor mismatch

Dynamic Data Optimization in IoT-Assisted Sensor Networks on Cloud Platform

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Computers, Materials & Continua 2022年第7期72卷 1357-1372页

作者： Nguyen A.Tuan D.Akila Souvik Pal Bikramjit Sarkar Thien Khai Tran G.Mothilal Nehru Dac-Nhuong Le Faculty of information Technology Ho Chi Minh City University of Foreign Languages-Information TechnologyHo Chi Minh City70000Vietnam Department of information Technology Vels Institute of ScienceTechnology&Advanced StudiesChennai600117India Department of Computer science and Engineering Sister Nivedita UniversityKolkata700156India Department of Computer science and Engineering JIS College of EngineeringNadia741235India institute of research and Development Duy Tan UniversityDanang550000Vietnam School of Computer science Duy Tan UniversityDanang550000Vietnam

This article presents a new scheme for dynamic data optimization in IoT(Internet of Things)-assisted sensor *** various components of IoT assisted cloud platform are *** addition,a new architecture for IoT assisted sensor networks is ***,a model for data optimization in IoT assisted sensor networks is proposed.A novel Membership inducing Dynamic Data Optimization Membership inducing Dynamic Data Optimization(MIDDO)algorithm for IoT assisted sensor network is proposed in this *** proposed algorithm considers every node data and utilized membership function for the optimized data *** proposed framework is compared with two stage optimization,dynamic stochastic optimization and sparsity inducing optimization and evaluated in terms of reliability ratio,coverage ratio and sensing *** optimization was performed based on the availability of cloud resource,sensor energy,data flow volume and the centroid of each *** was inferred that the proposed MIDDO algorithm achieves an average performance ratio of 76.55%,reliability ratio of 94.74%,coverage ratio of 85.75%and sensing error of 0.154.

关键词： Data optimization IoT sensor network reliability membership sensor energy

Strong electron–phonon coupling influences carrier transport and thermoelectric performances in group-IV/V elemental monolayers

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npj Computational Materials 2021年第1期7卷 1287-1298页

作者： Yu Wu Bowen Hou Ying Chen Jiang Cao Hezhu Shao Yiming Zhang Congcong Ma Heyuan Zhu Rongjun Zhang Hao Zhang Key Laboratory of Micro and Nano Photonic Structures(MOE)and Key Laboratory for information science of Electromagnetic Waves(MOE)and Department of Optical science and Engineering School of Information Science and TechnologyFudan UniversityShanghaiChina Department of Light Sources and Illuminating Engineering School of Information Science and TechnologyFudan UniversityShanghaiChina School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjingChina College of Electrical and Electronic Engineering Wenzhou UniversityWenzhouChina Yiwu research institute of Fudan University Yiwu CityZhejiangChina Nanjing University National Laboratory of Solid State MicrostructureNanjingChina

The interactions between electrons and phonons play the key role in determining the carrier transport properties in *** this work,comprehensive investigations on full electron–phonon(el–ph)couplings and their influences on carrier mobility and thermoelectric(TE)performances of 2D group IV and V elemental monolayers are performed,and we also analyze the selection rules on el–ph couplings using group *** shallow n/p-dopings in Si,Ge,and Sn,ZA/TA/LO phonon modes dominate the intervalley *** strong intervalley scatterings via ZA/TO phonon modes can be identified for CBM electrons in P,As,and Sb,and for VBM holes,ZA/TA phonon modes dominate intervalley scatterings in P while LA phonons dominate intravalley scatterings in As and *** considering full el–ph couplings,the TE performance for these two series of monolayers are predicted,which seriously downgrades the thermoelectric figures of merits compared with those predicted by the constant relaxation time approximation.

关键词： theory phonon coupling

Polarized red, green, and blue light emitting diodes fabricated with identical device configuration using rubbed PEDOT:PSS as alignment layer

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Chinese Physics B 2019年第7期28卷 116-121页

作者： Haoran Zhang Qi Zhang Qian Zhang Huizhi Sun Gang Hai Jing Tong Haowen Xu Ruidong Xia Key Laboratory for Organic Electronics & information Displays(KLOEID) Jiangsu–Singapore Joint Research Center for Organic/Bio Electronics &Information Displays Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications

Polarized red, green, and blue light emitting diodes(LEDs) are successfully fabricated using polyfluorene and its derivatives, namely, poly(9,9-dioctylfluorene)(PFO), poly(9,9-dioctylfluorene-co-benzothiadiazole)(F8BT),and poly(triphenylamine-co-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole-co-benzo[c]thiadiazole-co-9,9-dioctyl-9 Hfluorene)(Red F).Rubbed hole transport layer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate)(PEDOT:PSS)is employed in the devices as the alignment layer to achieve fully monodomain alignment in all polymer *** F is blended with F8BT to realize the polarized electroluminescence of red light(dichroic ratio ~3.3), despite having no liquid crystallinity *** PFO/F8BT blend to F8BT, higher efficiency of polarized emission is found due to the energy *** the polarized LEDs exhibit pronounced dichroism and efficient polarized emission compared to the non-alignment regular devices.

关键词： organic semiconductors light-emitting devices polymer liquid crystals display devices