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Research on vertical spatial characteristic of satellite infrared hyperspectral atmospheric sounding data

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Frontiers of Earth Science 2022年第2期16卷 265-276页

作者： ci song Qiu YIN School of Communication and Information Engineering Shanghai UniversityShanghai 200444China College of Science Zhongyuan University of TechnologyZhengzhou 450007China Shanghai Meteorological Service Shanghai 200030China User Office of Meteorological Satellites China Meteorological AdministrationShanghai 200030China

Spatial characteristic is an important indicator of remote sensor performance,and space-borne infrared hyperspectral sounder is the frontier of atmospheric vertical sounding *** this paper,the formation mechanism of the vertical spatial characteristics involved in the space-borne infrared hyperspectral sounding data are analyzed in detail,which shows that the vertical spatial characteristics of sounding data depends not only on the spectral channels and their waveband coverage,but also the specific atmospheric parameter and its specific variation *** indicators of vertical spatial characteristics are defined and their mathematical models are established based on the mechanism *** models are applied to the vertical spatial characteristic evaluation of atmospheric temperature sounding for FY-4A GIIRS,which is the first space-borne infrared hyperspectral atmospheric sounder in geostationary *** is concluded that FY-4A GIIRS can sound the vertical temperature distribution in whole troposphere and lower stratosphere with height<35 *** study can provide basic information to support the improvement of infrared hyperspectral sounder and the trace of vertical spatial characteristics of atmospheric inversion products.

关键词： infrared hyperspectral atmospheric sounding vertical spatial characteristic atmospheric temperature FY-4A GIIRS

Simulating CO_(2) profiles using NIES TM and comparison with HIAPER Pole-to-Pole Observations

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Frontiers of Earth Science 2023年第2期17卷 589-603页

作者： ci song Shamil MAKSYUTOV Jiong SHU College of Science Zhongyuan University of TechnologyZhengzhou 450007China National Institute for Environmental Studies Tsukuba 305-8506Japan Key Laboratory of Geographic Information Science Institute of Climate ChangeEast China Normal UniversityShanghai 200241China

We present a study on validation of the National Institute for Environmental Studies Transport Model(NIES TM)by comparing to observed vertical profiles of atmospheric CO_(2).The model uses a hybrid sigmaisentropic(σ–θ)vertical coordinate that employs both terrain-following and isentropic parts switched smoothly in the *** model transport is driven by reanalyzed meteorological fields and designed to simulate seasonal and diurnal cycles,synoptic variations,and spatial distributions of atmospheric chemical constituents in the *** model simulations were run for combination of biosphere,fossil fuel,air-ocean exchange,biomass burning and inverse correction fluxes of carbon dioxide(CO_(2))by GOSAT Level 4 *** compared the NIES TM simulated fluxes with data from the HIAPER Pole-to-Pole Observations(HIPPO)Merged 10-s Meteorology,Atmospheric Chemistry,and Aerosol Data,including HIPPO-1,HIPPO-2 and HIPPO-3 from 128.0°E to 84.0°W,and 87.0°N to 67.2°*** simulation results were compared with CO_(2) observations made in January and November,2009,and March and April,*** analysis attests that the model is sufficient to simulate vertical profiles with errors within 1–2 ppmv,except for the lower stratosphere in the northern hemisphere high latitudes.

关键词： HIPPO CO_(2) simulation vertical profile NIES-TM

Security in edge-assisted Internet of Things:challenges and solutions

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Science China(Information Sciences) 2020年第12期63卷 27-40页

作者： Shuaiqi SHEN Kuan ZHANG Yi ZHOU song ci Department of Electrical and Computer Engineering University of Nebraska-Lincoln School of Computer and Information Engineering Henan University Department of Electrical Engineering Tsinghua University

The flourish of 5th generation wireless systems(5G) network has brought numerous benefits to the Internet of Things(IoT) with universal connectivity, improved data rate, and decreased latency. The development of IoT extends the computation-intensive applications from centralized servers to the edge of the network, promoting the paradigm of edge computing. Edge computing brings great assistance to IoT architecture by efficiently accomplishing tasks with lower latency, less energy consumption and reduced network bandwidth. Edge-assisted IoT emerges to provide location-aware services and offload computational tasks to edge nodes near the IoT devices. However, a series of security challenges still exist in edge-assisted IoT owing to the inherent vulnerabilities of edge nodes and sensitive nature of the collected data. Among the emerging and existing security schemes in IoT applications, security and energy consumption are two overriding yet conflicting requirements. The tradeoff between security and energy is critical to the sustainability of the IoT ecosystem but still lacks sufficient discussion. In this article, we investigate the security challenges in edge-assisted IoT and how the constraints in energy consumption can affect the design of security ***, we firstly present the architecture of edge-assisted IoT and its unique characteristics. Secondly,we identify the security threats in the edge-assisted IoT applications and the security-energy tradeoff during implementation. Thirdly, in a case study of distributed denial of service(DDoS) and malware injection attack, we propose a preliminary solution to address the conflict between security and energy ***, we discuss some open issues and identify future research directions for security and energy efficiency in edge-assisted IoT.

关键词： Internet of Things edge computing network security machine learning data analytics

Global consistency check of AIRS and IASI total CO2 column concentrations using WDCGG ground-based measurements

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Frontiers of Earth Science 2017年第1期11卷 1-10页

作者： Anyuan DIAO Jiong SHU ci song Wei GAO Key Laboratory of Geographic Information Science (Ministry of Education) School of Geographic Sciences East China Normal University Shanghai 200241 China Colorado State University Department of Ecosystem Science and Sustainability Fort Collins Colorado 80523 USA Colorado State University Natural Resource Ecology Laboratory Fort Collins Colorado 80523 USA

This article describes a global consistency check of CO2 satellite retrieval products from the Atmospheric Infrared Sounder （AIRS） and Infrared Atmospheric Sounding Interferometer （IASI） using statistical analysis and data from the World Data Centre for Greenhouse Gases （WDCGG）. We use the correlation coefficient （r）, relative difference （RD）, root mean square errors （RMSE）, and mean bias error （MBE） as evaluation indicators for this study. Statistical results show that a linear positive correlation between AIRS/IASI and WDCGG data occurs for most regions around the world. Temporal and spatial variations of these statistical quantities reflect obvious differences between satellite-derived and ground-based data based on geographic position, especially for stations near areas of intense human activities in the Northern Hemisphere. It is noteworthy that there appears to be a very weak correlation between AIRS/IASI data and ten ground- based observation stations in Europe, Asia, and North America. These results indicate that retrieval products from the two satellite-based instruments studied should be used with great caution.

关键词： CO2 consistency check AIRS IASI WDCGG

Sensitivity studies of high-precision methane column concentration inversion using a line-by-line radiative transfer model

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Frontiers of Earth Science 2013年第4期7卷 439-446页

作者： ci song Jiong SHU Mandi ZHOU Wei GAO Key Laboratory of Geographic Information Science East China Normal University Shanghai 200241 China Department of Ecosystem Science and Sustainability Colorado State University Colorado 80523 USA

Hyper-spectral remote sensing may provide an effective solution to retrieve the methane （CH4） concentra- tion in an atmospheric column. As a result of exploring the absorptive characteristics of CH4, an appropriate band is selected from hyperspectral data for the detection of its column concentration with high precision. Following the most recent inversion theory and methods, the line-by-line radiative transfer model （LBLRTM） is employed to forward model the impact of four sensitive factors on inversion precision, including CH4 initial profile, tempera- ture, overlapping gases, and surface albedo. The results indicate that the four optimized factors could improve the inversion precision of atmospheric CH4 column concen- tration.

关键词： methane inversion radiance sensitivity forward model high precision

Cross-layer transmission and energy scheduling under full-duplex energy harvesting wireless OFDM joint transmission

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Science China(Information Sciences) 2016年第10期59卷 136-151页

作者： Hongjia LI Zejue WANG Dan HU song ci Zhen XU State Key Lab of Information Security Institute of Information EngineeringChinese Academy of Sciences cisco System Incorporated Department of Computer and Electronics Engineering University of Nebraska-Lincoln

This paper studies the design of the optimal and online cross-layer transmission and energy schedulings for a full-duplex energy harvesting wireless orthogonal frequency division multiplexing(OFDM) joint transmissions. Supported by today’s power management integrated circuit, the full-duplex energy harvesting system becomes a reality, which can overcome the transmission time loss problem caused by the half-duplex constraint of the energy storage unit(ESU) in the serial Harvest-Store-Use system. However, its corresponding modeling is still unexplored. Therefore, the full-duplex energy harvesting system is first modeled and proved to be equivalent to a composition of energy behavior models of Harvest-Store-Use in fine-time granularity. Then, the convex optimization problem of cross-layer transmission and energy scheduling is formulated with the objective to maximize the sum of transmission throughput during successively multiple time units, which takes into account the temporal variance of energy harvesting rates and channel states, and the limited capacity of *** optimal power allocation with three dimensions of time, channel and antenna is solved by utilizing the dual decomposition method with the pre-known temporal variance, and the corresponding result of the system throughput provides the theoretical upper bound. Finally, to reduce the throughput degradation caused by channel state prediction errors, a non-convex online scheduling problem is formulated as the classical energy efficiency format. It is transformed into a convex optimization problem by exploiting the properties of fractional programming, and then, an efficiently iterative solution is designed. Numerical results show that the average throughput of the online algorithm is 24% greater than that of existing time-energy adaptive water-filling algorithm. The degradation of the average throughput is less than 19% with probability 90%, even as the channel prediction error reaches 20%. These results pro

关键词： energy harvesting wireless communication power allocation joint transmission optimization green communication

Pb, Cu botanogeochemical anomalies and toxic effects on plant cells in Pb-Zn (Sn) ore fields, Northeast Guangxi Autonomous Region, China

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Chinese Journal Of Geochemistry 2007年第3期26卷 329-332页

作者： song ci＇an LEI Liangqi YANG Qijun Department of Resources and Environment Engineering Guilin University of Technology Guilin 541004 China

In the Lingchuan-Daoping and Xinglu Pb-Zn ore fields in northern and eastern Guangxi Autonomous Region, Pb, Cu botanogeochemical anomalies may be ascribed to the excessive amounts of Pb and Cu taken up by the root system of plants, such as China fir (Cunninghamia lanceolata Lamb. Hook), mason pine (Pinus massoniana Lamb.) and bracken fern (Pteridium aquilinum var. latiusculum). Under transmission electron microscope (TEM), the excess Pb, Cu in the leaf cells of the plants are present as high electron-density substances, which were precipitated in the leaf cells, causing phytotoxic effects by deforming and injuring cellular tissues. The sorts of toxic elements accumulating in the leaf cells are consistent with those of the botanogeochemically anomalous elements in the polluted soil where the plants grow. In addition, the plants may also be capable of resisting the invasion of excess Cu (and Pb) .

关键词：铅铜植物化学植物性中毒

Building a Cloud-Based Energy Storage System through Digital Transformation of Distributed Backup Battery in Mobile Base Stations

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China Communications 2020年第4期17卷 42-50页

作者： song ci Yanglin Zhou Yuan Xu Xingjian Diao Junwei Wang Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Shanghai Institute of Microsyst&Information Technology CASShanghai 200050China Guangzhou Power Supply Bureau Guangdong Power Grid Co.LtdGuangzhou 510620China Department of Computer Science University of PittsburghPA15260USA China Tower Company Limited Guangzhou518000China School of Information Science&Technology ShanghaiTech UniversityShanghai 200210China University of Chinese Academy of Sciences Beijing100039China

Battery energy storage systems(ESS) have been widely used in mobile base stations(BS) as the main backup power source. Due to the large number of base stations, massive distributed ESSs have largely stayed in idle and very difficult to achieve high asset utilization. In recent years, the fast-paced development of digital energy storage(DES) technology has revolutionized the traditional operation and maintenance of ESSs by transforming them into digital assets, further enabling battery energy storage services, raising up a new way to achieve a much higher utilization of such kind of largely idle ESS resources. In this paper, the disruptive DES technology will be introduced and its application under the context of mobile BSs will be studied, and then a cloud-based energy storage(CES) platform is proposed based on a large scale distributed DESs to provide a new cyber-enabled energy storage service to the local utility company. A real-world case study shows the effectiveness and efficiency of the CES platform.

关键词： digital energy storage dynamic reconfigurable battery network energy digitization software-defined battery system cloud energy storage

Communication Resources Allocation for Time Delay Reduction of Frequency Regulation Service in High Renewable Penetrated Power System

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 468-480页

作者： Hongjie He Ning Zhang Chongqing Kang song ci Fei Teng Goran Strbac State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Department of Electrical and Electronic Engineering Imperial College LondonSW72BULondonU.K

The high renewable penetrated power system has severe frequency regulation *** resources can provide frequency regulation services but are limited by com-munication time *** paper proposes a communication resources allocation model to reduce communication time delay in frequency regulation *** device resources and wireless spectrum resources are allocated to distributed resources when they participate in frequency *** reveal impact of communication resources allocation on time delay reduction and frequency regulation ***,we study communication resources allocation solution in high renewable energy penetrated power *** provide a case study based on the HRP-38 *** show communication time delay decreases distributed resources'ability to provide frequency regulation *** the other hand,allocating more communication resources to distributed resources'communica-tion services improves their frequency regulation *** power systems with renewable energy penetration above 70%,required communications resources are about five times as many as 30%renewable energy penetrated power systems to keep frequency performance the *** Terms-Communication resources allocation,commun-ication time delay,distributed resource,frequency regulation,high renewable energy penetrated power system.

关键词： Communication resources allocation communication time delay distributed resource frequency regulation high renewable energy penetrated power system