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Different Warming Patterns of Tropical Pacific Sea Surface Temperature Projected by FGOALS-g2 and FGOALS-s2 under RCP8.5

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Atmospheric and Oceanic science Letters 2015年第2期8卷 82-87页

作者： ZHANG Li-Xia ZHOU Tian-Jun State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Joint center for Global Change Studies (JCGCS)

The different patterns of SST changes under the ＋8.5 W m 2 Representative Concentration Pathway （RCP8.5） projected by the latest two versions of the Flexible Global Ocean-Atmosphere-Land System model （FGOALS-g2 and FGOALS-s2; grid-point version 2 and spectral version 2, respectively）, and the potential mecha- nisms for their formation are studied in this paper. The results show that, although both FGOALS-g2 and FGOALS-s2 project global warming patterns, FGOALS-g2 （FGOALS-s2） projects a La Nifia-like （an E1 Nifio-like） mean warming pattern with weakest （strongest） warming over the central （eastern） equatorial Pacific for 2081-2100 relative to 1986-2005 under RCP8.5. A mixed layer heat budget analysis shows that the projected tropical Pacific Ocean warming in both models is primarily caused by atmos- pheric forcing. The main differences in the heating terms contributing to the SST changes between the two models are seen in the downward longwave radiation and ocean forcing. The minimum SST warming over the equatorial Pacific in FGOALS-g2 is attributed to the local minimum heating of downward longwave radiation and maximum cooling of ocean forcing. In contrast, the maximum SST warming over the equatorial Pacific in FGOALS-s2 is due to the maximum warming of downward longwave radia- tion, and the contribution of ocean forcing is minor. The minimum SST warming over the equatorial Pacific in FGOALS-g2 emerges around the 2050s, before when the SST over the equatorial Pacific is warmer than that over the extra-equatorial Pacific. In FGOALS-s2, the SST dif- ference shows a continuous increasing trend for 2006- 2100. Further examination of the oceanic and atmospheric circulation changes is needed to reveal the process responsible for the longwave radiation and ocean forcing difference between the two models.

关键词： climate model SST projection heat budget

Assembly and analysis of the Populus deltoides mitochondrial genome:the first report of a multicircular mitochondrial conformation for the genus Populus

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Journal of Forestry Research 2023年第3期34卷 717-733页

作者： Yanshu Qu Pengyan Zhou Chunfa Tong Changwei Bi Li’an Xu Key Laboratory of Forestry Genetics&Biotechnology of Ministry of Education Co-Innovation Center for Sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037People’s Republic of China College of information science and Technology Nanjing Forestry UniversityNanjing 210037People’s Republic of China

Genomics research of Populus deltoides,an important timber species that is widely planted worldwide,is an important part of poplar ***,the nuclear and chloroplast genome of *** have been sequenced,but its mitochondrial genome(mitogenome)has not been *** further explore the evolution and phylogeny of ***,the mitogenome of *** I-69 was assembled using reads from Nanopore and Illumina sequencing platforms and found to consist of 802,637 bp and three circular chromosomes(336,205,280,841,and 185,591 bp)containing 58 genes(34 protein-coding genes,21 tRNA genes,and 3 rRNA genes).RNA analysis in combination with several species showed signifi cantly fewer RNA editingsites in the mitogenomes of poplar and other angiosperms than in *** transfer analysis showed extensive mitogenome rearrangements in Populus species,and with evolution from lower to higher plants,tRNA transfer from chloroplasts to mitochondria became increasingly *** a phylogenetic analysis,the evolutionary status of *** was determined,and the section Populus was *** results based on the fi rst report of a multicircular conformation of the Populus mitogenome provide a basis for further study of the evolution and genetics of *** and other Populus species and for breeding programs.

关键词： Mitochondrial genome Multi-circular Populus deltoids Comparative genomics Phylogeny

Observational study of the physical and chemical characteristics of the winter radiation fog in the tropical rainforest in Xishuangbanna, China

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science China Earth sciences 2021年第11期64卷 1982-1995页

作者： Yuan WANG Shengjie NIU Chunsong LU Jingjing LV Jing ZHANG Hongwei ZHANG Sirui ZHANG Naifu SHAO Wei SUN Yuchen JIN Qinghai SONG Collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters and Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&Technology(NUIST)Nanjing 210044China College of Safety science and Engineering Nanjing Tech UniversityNanjing 210009China Key Laboratory of Tropical Forest Ecology(TFE) Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences(CAS)Menglun 666303China Henan Meteorological Observation and Data center Zhengzhou 450003China

We conducted a three-month field experiment focusing on the physical and chemical characteristics of fog in a tropical rainforest in Xishuangbanna,Southwest China,in the winter of *** general,the fog would form at midnight and persist because of the increased long-wave radiative cooling combined with the high relative humidity,gentle breeze,and a relatively low aerosol number concentration in the forest;the fog would dissipate before noon due to the increasing turbulence near the *** diurnal cycle is typical for radiation *** microphysical fog properties included a relatively low number concentration of the fog droplet,large droplet size,high liquid water content,narrow droplet number-size distribution,and high *** chemical properties showed that the fog water was slightly alkaline with low electrical conductivity,whereas the highest proportions of anions and cations therein were Cl^(−)and Ca^(2+),respectively;the chemical components were enriched in small fog *** addition,we indirectly calculated the fog supersaturation according to theκ-Köhler *** found that condensation broadens the droplet number-size distribution at relatively low supersaturation,which is positively correlated with the fog-droplet number concentration and negatively correlated with the droplet mean-volume diameter;this affects the key microphysical processes of fog.

关键词： Radiation fog Formation and disappearance mechanisms Physical and chemical characteristics Supersaturation Tropical rainforest

Channel Characteristics Based on Ray Tracing Methods in Indoor Corridor at 300 GHz

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Journal of Donghua University(English Edition) 2021年第3期38卷 221-230页

作者： ZHAI Kai ZHAI Menglin ZHANG Lei LI Demin College of information science and Technology Donghua UniversityShanghai 201620China Engineering Research center of Digitized Textile and Apparel Technology Ministry of Education Donghua University Shanghai 201620 China

With the rapid development of communication technology,people's demand for ultra-high-speed wireless links becomes higher,among which terahertz spectra are considered as one of the most promising *** this paper,we analyze the channel characteristics at 300 GHz in indoor corridor based on ray tracing methods,including the large-scale and small-scale fading *** results show that it is suitable for short distance transmission due to its large path loss(PL).Firstly,compared with line-of-sight(LoS),the correlation of frequency components in non-line-of-sight(NLoS)is much better,but LoS has more abundant circle angular spread(CAS).Then,a stochastic model is well derived to describe the distance-dependent behaviour of root-mean-square delay spread(RMS-DS)as well as root-mean-square CAS(RMS-CAS).Besides,we find that the channel capacity can effectively increase by increasing the transmitted power in both LoS and ***,it can be seen that the RMS-DS can be significantly reduced in LoS and the channel capacity can increase by changing the position of the *** simulation results will provide references for future indoor communication.

关键词： terahertz channel characteristic ray tracing indoor corridor

Path Planning and Navigation of Oceanic Autonomous Sailboats and Vessels: A Survey

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Journal of Ocean University of China 2020年第3期19卷 609-621页

作者： JING Wei LIU Chao LI Ting RAHMAN A B M Mohaimenur XIAN Lintao WANG Xi WANG Yu GUO Zhongwen BRENDA Gumede TENDAI Wachi Kelvin Department of Computer Fundamentals Ocean University of ChinaQingdao 266100China College of information science and Engineering Ocean University of ChinaQingdao 266100China Department of Computer science University of North Carolina at CharlotteCharlotteNC 28233USA Department of Computer and information sciences Temple UniversityPhiladelphiaPennsylvania 19122USA

Oceanic autonomous surface vehicles(ASVs) are one kind of autonomous marine robots that have advantages of energy saving and is flexible to use. Nowadays, ASVs are playing an important role in marine science, maritime industry, and national defense. It could improve the efficiency of oceanic data collection, ensure marine transportation safety, and protect national security. One of the core challenges for ASVs is how to plan a safe navigation autonomously under the complicated ocean environment. Based on the type of marine vehicles, ASVs could be divided into two categories: autonomous sailboats and autonomous vessels. In this article, we review the challenges and related solutions of ASVs' autonomous navigation, including modeling analysis, path planning and implementation. Finally, we make a summary of all of those in four tables and discuss about the future research directions.

关键词： autonomous sailboats autonomous vessels model analysis path planning

Visualisation techniques to support public interpretation of future climate change and land-use choices:a case study from N-E Scotland

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International Journal of Digital Earth 2016年第6期9卷 586-605页

作者： Chen Wang David Miller Iain Brown Yang Jiang Marie Castellazzi information and Computational sciences The James Hutton InstituteAberdeenUK School of Computing science and Digital Media Robert Gordon UniversityAberdeenUK

Mitigating and adapting to climate change includes a requirement to evaluate the role of future land uses in delivering robust integrated responses that are sensitive to local landscape *** practice,this emphasises the need for community engagement,planning and inclusive *** engagement may be potentially facilitated by the use of spatially explicit quantitative scenarios of landuse change in combination with interactive *** requires a coherent framework to integrate spatial data modelling,analytical capabilities and visualisation tools in a format that will also engage diverse public *** challenges were explored with a case study of virtual landscapes from N-E Scotland that was used to test preferences for scenarios of future land *** employed texture-based rendering rather than full photo-realistic rendering to facilitate interactivity and this provided additional scope for audiences to explore multiple future scenarios compared to the present *** voting in a virtual landscape theatre suggested preferences for visual diversity,good stewardship and perceived naturalness that should be considered in developing planned responses to *** investigation of preferences was conducted using interactive 3D features located within the *** findings are reviewed against objectives for inclusive engagement in the Digital Earth agenda and used to make further recommendations on the use of scenarios and visualisation *** particular,technical advances in user engagement need to be developed in conjunction with emerging good practice that addresses ethical,behavioural and inclusion issues so that the content is presented in as transparent and unbiased format as possible.

关键词： Landscape visualisation geographic information systems land-use scenarios public participation knowledge exchange

Disturbance Observer Design with a Bode’s Ideal Filter for Sigma-Delta Modulators

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Journal of Harbin Institute of Technology(New Series) 2020年第1期27卷 61-66页

作者： Chi Xu Yu Jin Hang Liu Duli Yu College of information science and Technology Beijing University of Chemical TechnologyBeijing 100029China Advanced Innovation center for Soft Matter Beijing University of Chemical TechnologyBeijing 100029China

It is usually difficult to design a high performance Sigma⁃Delta(ΣΔ)modulator due to system *** this paper,a disturbance observer(DOB)is utilized to estimate the system noises and eliminate their effects on ΣΔ *** applied DOB is introduced with a Bode's ideal cut⁃off(BICO)filter used for the Q⁃*** proposed DOB with the BICO filter used in ΣΔ modulators can achieve better noise⁃shaping ability,resulting from the less phase loss of the BICO ***,the simulation results show that the proposed BICO filter scheme is a useful additional tool for improving the performance of ΣΔ modulators.

关键词： DOB ΣΔmodulator BICO filter noise⁃shaping fractional⁃order system

Analysis of Dynamic Characteristics of the 21st Century Maritime Silk Road

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Journal of Ocean University of China 2018年第3期17卷 487-497页

作者： ZHANG Xudong ZHANG Jie FAN Chenqing MENG Junmin WANG Jing WAN Yong College of information science and Engineering Ocean University of China Qingdao 266100 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China College of information and Control Engineering in China University of Petroleum Qingdao 266580 China

The 21st century Maritime Silk Road(MSR) proposed by China strongly promotes the maritime industry. In this paper, we use wind and ocean wave datasets from 1979 to 2014 to analyze the spatial and temporal distributions of the wind speed, significant wave height(SWH), mean wave direction(MWD), and mean wave period(MWP) in the MSR. The analysis results indicate that the Luzon Strait and Gulf of Aden have the most obvious seasonal variations and that the central Indian Ocean is relatively stable. We analyzed the distributions of the maximum wind speed and SWH in the MSR over this 36-year period. The results show that the distribution of the monthly average frequency for SWH exceeds 4 m(huge waves) and that of the corresponding wind speed exceeds 13.9 ms^(-1)(high wind speed). The occurrence frequencies of huge waves and high winds in regions east of the Gulf of Aden are as high as 56% and 80%, respectively. We also assessed the wave and wind energies in different seasons. Based on our analyses, we propose a risk factor(RF) for determining navigation safety levels, based on the wind speed and SWH. We determine the spatial and temporal RF distributions for different seasons and analyze the corresponding impact on four major sea routes. Finally, we determine the spatial distribution of tropical cyclones from 2000 to 2015 and analyze the corresponding impact on the four sea routes. The analysis of the dynamic characteristics of the MSR provides references for ship navigation as well as ocean engineering.

关键词： Maritime Silk Road risk factor ocean wave wind speed tropical cyclone

A Deep Two-State Gated Recurrent Unit for Particulate Matter (PM_(2.5)) Concentration Forecasting

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Computers, Materials & Continua 2022年第5期71卷 3051-3068页

作者： Muhammad Zulqarnain Rozaida Ghazali Habib Shah Lokman Hakim Ismail Abdullah Alsheddy Maqsood Mahmud Faculty of Computer science and information Technology Universiti Tun Hussein Onn MalaysiaBatu PahatJohorMalaysia College of Computer science King Khalid UniversityAbhaSaudi Arabia College of Computer and information sciences Imam Mohammad Ibn Saud Islamic UniversityRiyadhSaudi Arabia Department of Management information Systems College of Business AdministrationImam Abdulrahman Bin Faisal University31441DammamSaudi Arabia

Air pollution is a significant problem in modern societies since it has a serious impact on human health and the *** Matter(PM_(2.5))is a type of air pollution that contains of interrupted elements with a diameter less than or equal to 2.5 *** risk assessment and epidemiological investigations,a better knowledge of the spatiotemporal variation of PM_(2.5) concentration in a constant space-time area is *** spatiotemporal interpolation approaches commonly relying on robust presumption by limiting interpolation algorithms to those with explicit and basic mathematical expression,ignoring a plethora of hidden but crucial manipulating *** advanced deep learning approaches have been proposed to forecast Particulate Matter(PM_(2.5)).Recurrent neural network(RNN)is one of the popular deep learning architectures which is widely employed in PM_(2.5) concentration *** this research,we proposed a Two-State Gated Recurrent Unit(TS-GRU)for monitoring and estimating the PM_(2.5) concentration forecasting *** proposed algorithm is capable of considering both spatial and temporal hidden affecting elements *** tested our model using data from daily PM_(2.5) dimensions taken in the contactual southeast area of the United States in *** the studies,three evaluation matrices were utilized to compare the overall performance of each algorithm:Mean Absolute Error(MAE),Root Mean Square Error(RMSE),and Mean Absolute Percentage Error(MAPE).The experimental results revealed that our proposed TS-GRU model outperformed compared to the other deep learning approaches in terms of forecasting performance.

关键词： Deep learning PM_(2.5)forecasting air pollution two-state GRU