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Solar Flare Forecast Model Based on Resampling and Fusion Method

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Research in Astronomy and Astrophysics 2022年第8期22卷 238-248页

作者： Jie Wan Jun-Feng Fu Dai-Min tan Ke Han Meng-Yao Yu Peng E Laboratory for Space Environment and Physical Sciences Harbin Institute of TechnologyHarbin 150001China School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China School of Computer and Information Engineering Harbin University of CommerceHarbin 150028China

Predicting the activity of solar flares is of great significance for studying its physical mechanism and the impact on human production and *** such as class imbalance,high time-series sensitivity,and over-localization of important features exist in the sample data used for flare *** design a solar flare fusion method based on resampling and the CNN-GRU algorithm to try to solve the above *** order to verify the effectiveness of this fusion method,first,we compared the forecast performance of different resampling methods by keeping the forecast model ***,we used the resampling algorithm with high performance to combine some single forecast models and fusion forecast models *** use the 2010-2017 sunspot data set to train and test the performance of the flare model in predicting flare events in the next 48 *** the conclusion of the above steps,we prove that the resampling method SMOTE and its variant SMOTE-ENN are more advantageous in class imbalance problem of flare *** addition,after the fusion of one-dimensional convolution and recurrent network with"forget-gate",combined with the SMOTE-ENN to achieve TSS=61%,HSS=61%,TP_(Rate)=77%and TN_(Rate)=83%.This proves that the fusion model based on resampling and the CNN-GRU algorithm is more suitable for solar flare forecasting.

关键词： (Sun:)sunspots Sun:flares Sun:X-rays gamma-rays Sun:magnetic fields Sun:corona

Influence of mesoscale eddies on primary production in the South China Sea during spring inter-monsoon period

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Acta Oceanologica Sinica 2014年第3期33卷 118-128页

作者： HU Zifeng tan Yehui SONG Xingyu ZHOU Linbin LIAN Xiping HUANG Liangmin HE Yinghui Key Laboratory of Marine Bio-resources Sustainable Utilization (LMB) South China Sea Institute of Oceanology Chinese Academy of Sciences University of Chinese Academy of Sciences Marine Biology Research Station at Daya Bay Chinese Academy of Science State Key Laboratory of Tropical Oceanology (LTO) South China Sea Institute of Oceanology ChineseAcademy of Sciences

Mesoscale eddies have been suggested to have an impact on biological carbon fixation in the South China Sea （SCS）. However, their overall contribution to primary production during the spring inter-monsoon pe riod is still unknown. Based on large-scale biological and environmental in situ observations and synchro nous remote sensing data, the distribution patterns of phytoplankton biomass and the primary production, and the role of mesoscale eddies in regulating primary production in different eddy-controlled waters were investigated. The results suggested that the surface chlorophyll a concentrations and water column inte grated primary production （IPP） are significantly higher in cyclonic eddies and lower in the anticyclonic eddies as compared to that in non-eddy waters. Although eddies could affect various environmental factors, such as nutrients, temperature and light availability, nutrient supply is suggested to be the most important one through which mesoscale eddies regulated the distribution patterns of phytoplankton biomass and pri mary production. The estimated IPP in cyclonic and anticyclonic eddies are about 29.5% higher and 16.6% lower than the total average in the whole study area, respectively, indicating that the promotion effect of mesoscale cold eddies on the primary production was much stronger than the inhibition effect of the warm eddies per unit area. Overall, mesoscale eddies are crucial physical processes that affect the biological car bon fixation and the distribution pattern of primary production in the SCS open sea, especially during the spring inter-monsoon period.

关键词： mesoscale eddies chlorophyll a primary production vertically generalized production model,remote sensing South China Sea

Initial allocation of carbon emission permits in power systems

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Journal of Modern Power Systems and Clean Energy 2017年第2期5卷 239-247页

作者： tan WANG Xu WANG Yu GONG Chuanwen JIANG Fengjia XIONG Lei LI Yan ZHAO Electrical Engineering Department Shanghai Jiao Tong UniversityShanghai 200240China Henry Samueli School of Engineering and Applied Science University of CaliforniaLos Angeles 90024USA Electric Power Transaction Center Shanghai Municipal Electric Power CompanyShanghai 200122China

Initial allocation modes and schemes are studied in this paper to provide guidelines for allocation of carbon emission permits in power system. We first introduce different allocation modes and the need to apply free allocation to assignability of emission permits. Then, we compare two different allocation schemes, which are based on historical emissions and generation performance standard. Further, a new allocation scheme based on Boltzmann distribution is proposed. Finally, a case study on Shanghai power grid in China is conducted to compare the allocation effects of these schemes respectively. The analytical results show that Boltzmann distribution based scheme has the best performance and should be adopted when developing initial allocation of carbon emission permits in Chinese power systems.

关键词： Carbon emission permits Initial allocation Generation performance standard Boltzmann distribution

三峡水库干流与香溪河库湾水体营养状态及其对水文条件的响应

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长江流域资源与环境 2021年第6期30卷 1488-1499页

作者：谭路申恒伦王岚蔡庆华中国科学院水生生物研究所淡水生态与生物技术国家重点实验室湖北武汉430072 枣庄学院生命科学学院山东枣庄277160

基于三峡水库干流和香溪河库湾2003年7月至2013年7月10年间的水质数据,采用Carlson营养状态指数营养状态指数及差值二维坐标评价方法,阐述三峡水库干流和香溪河库湾在蓄水前后10年以来的营养水平,评价其水体营养状态及其限制限制因素,... 详细信息

基于三峡水库干流和香溪河库湾2003年7月至2013年7月10年间的水质数据,采用Carlson营养状态指数营养状态指数及差值二维坐标评价方法,阐述三峡水库干流和香溪河库湾在蓄水前后10年以来的营养水平,评价其水体营养状态及其限制限制因素,通过建立干支流中营养状态与水动力条件的关系,判断在干支流上水动力条件是否是富营养化的限制因子。结果表明:蓄水10年来,三峡水库水体营养状态没有出现显著的上升或下降趋势。在三峡水库长江干流水动力条件对营养盐利用几乎没有调控作用。与水库干流不同,在香溪河支流库水动力条件在一定程度上能影响藻类对营养盐的利用,即可通过调节香溪河支流库湾水动力条件来控制藻类水华的发生。

关键词：三峡水库香溪河库湾富营养化营养限制水动力

Some New Exact Solutions of Jacobian Elliptic Function of Petviashvili Equation

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Communications in Theoretical Physics 2008年第6期49卷 1557-1560页

作者： ZHANG Ling ZHANG Li-Feng LI Chong-Yin WANG Tie tan Yan-Ke Institute of Meteorology PLA University of Science and Technology Laboratory of Applied Geophysics Nanjing 211101 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics the Chinese Academy of Sciences Beijing 100029 China

By using the modified mapping method, we find new exact solutions of the Petviashvili equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function so... 详细信息

关键词： Petviashvili equation Jacobian elliptic function modified mapping method

Image Recognition of Citrus Diseases Based on Deep Learning

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Computers, Materials & Continua 2021年第1期66卷 457-466页

作者： Zongshuai Liu Xuyu Xiang Jiaohua Qin Yun tan Qin Zhang Neal N.Xiong Central South University of Forestry and Technology Changsha410004China School of Information Technology and Management Hunan University of Finance and EconomicsChangsha410205China Department of Mathematics and Computer Science Northeastern State UniversityTahlequahOK74464USA

In recent years,with the development of machine learning and deep learning,it is possible to identify and even control crop diseases by using electronic devices instead of manual *** this paper,an image recognition method of citrus diseases based on deep learning is *** built a citrus image dataset including six common citrus *** deep learning network is used to train and learn these images,which can effectively identify and classify crop *** the experiment,we use MobileNetV2 model as the primary network and compare it with other network models in the aspect of speed,model size,*** show that our method reduces the prediction time consumption and model size while keeping a good classification ***,we discuss the significance of using MobileNetV2 to identify and classify agricultural diseases in mobile terminal,and put forward relevant suggestions.

关键词： Deep learning image classification citrus diseases agriculture science and technology

Genetic and logic networks with the signal-inhibitor-activator structure are dynamically robust

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Progress in Natural Science:Materials International 2006年第12期16卷 1329-1336页

作者： LI Fangting** and tan Ning(School of Physics and Centre for Theoretical Biology, Peking University, Beijing 100871, China) School of Physics and Centre for Theoretical Biology Peking University Beijing 100871 China

The proteins, DNA and RNA interaction networks govern various biological functions in living cells, these networks should be dynamically robust in the intracellular and environmental fluctuations. Here, we use Boolean network to study the robust structure of both genetic and logic networks. First, SOS network in bacteria E. coli, which regulates cell survival and repair after DNA damage, is shown to be dynamically robust. Comparing with cell cycle network in budding yeast and flagella network in E. coli, we find the signal-inhibitor-activator (SIA) structure in transcription regulatory networks. Second, under the dynamical rule that inhibition is much stronger than activation, we have searched 3-node non-self-loop logical networks that are dynamically robust, and that if the attractive basin of a final attractor is as large as seven, and the final attractor has only one active node, then the active node acts as inhibitor, and the SIA and signal-inhibitor (SI) structures are fundamental architectures of robust networks. SIA and SI networks with dynamic robustness against environment uncertainties may be selected and maintained over the course of evolution, rather than blind trial-error testing and being an accidental consequence of particular evolutionary history. SIA network can perform a more complex process than SI network, and SIA might be used to design robust artificial genetic network. Our results provide dynamical support for why the inhibitors and SIA/SI structures are frequently employed in cellular regulatory networks.

关键词： genetic network signal-inhibitor-activator (SIA) structure Boolean network model dynamical robust.

Effect of micro/nano-sheet array structures on the osteo-immunomodulation of macrophages

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Regenerative Biomaterials 2022年第1期9卷 888-899页

作者： Xinhui Zheng Lan Chen Ji tan Jianhua Miao Xuanyong Liu Tieyi Yang Zhihong Ding Department of Orthopedics Gongli Hospital of Shanghai Pudong New AreaShanghai 200135China Department of Orthopedics Zhengzhou Central Hospital Affiliated Zhengzhou UniversityZhengzhou 450007China State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Materials Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou UniversityZhengzhou 450001China

The immune response induced by surface topography crucially determines the implant ***,how the immune response is mediated by the size of surface topography remains ***,various biocompatible Mg-Al layered double hydroxides sheet-array films with different sizes(nano,micro and nano/micro mixture)were constructed on the biomedical titanium,and their osteo-immunomodulation effects on the macrophages were *** nano-sheet array structures significantly promoted the polarization of M2 macrophages by activating the PI3K-AKT-mTOR signaling pathway with high gene expressions of integrin b2 and *** the micro-sheet array structures enhanced osteogenic differentiation of mouse bone marrow mesenchymal stem cells(mBMSCs)via ROCK-YAP/TAZ-mediated ***,the nano-sheet array structures promoted the osteogenic differentiation of mBMSCs with a high proportion of M2 macrophages through a shared *** study gave further information concerning integrin-induced focal adhesions in cells of different sheet array structures and their role in macrophage polarization and osteogenic differentiation of mBMSCs,which might help to design biomaterial surfaces with optimal geometry for a desired immunemodulation.

关键词： micro-nano topography immunomodulation macrophages osteogenesis

Assessment of the macro-economic impacts of low-carbon road transportation policies in Chongqing,China

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Advances in Climate Change Research 2020年第4期11卷 429-441页

作者： tan Xian-Chun ZENG Yuan GU Bai-He tanG Jie WANG Dong GUO Jian-Xin Institutes of Science and Development Chinese Academy of SciencesBeijing100190China School of Economics and Management Harbin Institute of TechnologyShenzhen518055China University of Chinese Academy of Sciences Beijing100190China

Reductions in the transportation sector's carbon dioxide emissions are increasingly of global *** one of the first low-carbon pilot and carbon trading pilot cities,and as one of the largest automobile production bases in China,Chongqing has multiple low-carbon transportation policies that are *** this study,three policy scenarios are set,including:1)improving the fuel economy of newly sold gasoline passenger cars to 5.71 per 100 km by 2020,2)promoting pure electric private cars to increase the share to 7% of private car sales by 2020,and 3)the policy mix scenario of the above two *** are undertaken with the Chinese Academy of Sciences general equilibrium(CAS-GE)model,a type of computable GE model,to assess the macro-economic impact and the industrial impact of the three policy *** the policy impact mechanism analysis and data-mapping process,the micro-economic impact analysis results,including costs and fuel savings,for the two policies from the bottom-up model are taken as the shock variables and inputs for the CAS-GE *** results show that:1)the two policies will both have a slightly negative impact(-0.09% and -0.30%)on Chongqing's GDP in 2020;2)the employment rate will decrease by 0.12% and 0.47%,but the inflation rate will be restrained to a certain extent(-0.21% and -0.17%);and 3)the complementarity of the mixed policy can weaken the negative impact of the two policies when implemented *** mixed policy will reduce the GDP slightly by 0.37%,compared with the cumulative effect of the two policies implemented separately,resulting in cost-effective synergies at the macroeconomic impact level;and 4)the COVID-19 pandemic in 2020 has an uncertain impact on the *** method and results can provide a reference for the formulation and adjustment of low-carbon transportation policies in other large cities.

关键词： Low-carbon road transportation policies Policy impact mechanism Macro-economic impact modeling Mixed policy analysis Chongqing