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Rice stem lodging properties and bending modeling under the influence of circadian temperature difference

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 21-32页

作者： Bangzhui Wang Zhong tang Liyun Lao guoqiang Wang Tiantian Jing Yao Yu School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina School of Water Energy and EnvironmentCranfield UniversityMK430ALUK Department of Agricultural Engineering Jiangsu Agriculture&Animal Husbandry Science and Technology Vocational CollegeTaizhou 225300JiangsuChina

Under diurnal temperature stress,the vascular bundle content of mature rice stems will change which will cause a change in the modulus of ***,the rice stems will collapse with the reduction in bending resistance because of the change in the modulus of *** order to reveal the distribution of vascular bundle gradients in rice stems under different climatic temperatures and explore the locations where stems are prone to bending and the form of stem damage,this study established a model of stem stiffness under free loading based on observing microstructure of the *** lodging characteristics of rice stems was explored seldom in different environmental temperatures from a micro structure of rice ***,the statistical analysis and t-tests were carried out on stems 1 to 4 in combination for cantilever bending tests at room temperature on stem internodes 3,versus three-point bending tests at-10℃ to 65℃ temperature *** showed that the bending resistance of the stem can be well predicted by using the vascular bundle distribution regression model and the variable stiffness mechanical *** bending resistance of No.3 stem was established by using the results obtained from the three-point bending test in a temperature range between 10℃-65℃.The correction coefficient TF of stem bending resistance under temperature difference induced stress was established based on the Gauss regression *** analysis showed that the bending resistance of No.3 stem was relatively large in a temperature range of 16℃-34℃.This study elucidated the variations of the mechanical properties of rice stems under temperature difference induced stress and provided a theoretical foundation for understanding the lodging characteristics of rice during mechanized harvesting.

关键词： rice stem vascular gradient stiffness model stem bending temperature stress

Oil Price Forecasting Based on EMD and BP_AdaBoost Neural Network

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Open Journal of Statistics 2018年第4期8卷 660-669页

作者： Huifang Qu guoqiang tang Qiying Lao College of Science Guilin University of Technology Guilin China

Empirical mode decomposition (EMD) and BP_AdaBoost neural network are used in this paper to model the oil price. Based on the benefits of these two methods, we predict the oil price by using them. To a certain extent, it effectively improves the accuracy of short-term price forecasting. Forecast results of this model are compared with the results of the ARIMA model, BP neural network and EMD-BP combined model. The experimental result shows that the root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE) and Theil inequality (U) of EMD and BP_AdaBoost model are lower than other models, and the combined model has better prediction accuracy.

关键词： Empirical Mode Decomposition (EMD) BP_AdaBoost Model Oil Price

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红肉苹果新品种玖红1号的选育

中国果树 2024年第1期 115-117页

作者：贾丽朱学亮王妍唐国强李善立李国栋王延书齐河县行政审批服务局山东251100 济南市林果技术推广和产业服务中心济南正庄农业科技有限公司山东中康裕农农业科技有限公司山东省农业技术推广中心临沂市农业技术推广中心

玖红1号是济南正庄农业科技有限公司选育的红肉苹果优良新品种。平均单果重237 g,果实圆锥形,果面鲜红色。果肉玫瑰红色,肉质硬脆,风味酸甜,可溶性固形物含量13.6%。早果性、丰产性、抗逆性均较强。在山东省济南地区,果实9月底成熟。

关键词：玖红1号红肉苹果新品种

Tail Dependence Study of SSE Composite Index and SZSE Component Index Based on the Copula

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Applied Mathematics 2013年第7期4卷 1065-1069页

作者： Guohua Sun Hongliu Su guoqiang tang College of Science Guilin University of Technology Guilin China

With the rapid development of financial industry, copula methods are more and more widely used for the study of financial fields. By selecting the appropriate copulas, the tail dependence of financial variables can be measured easily. Using the nonparametric estimation method to select A12 copula from Archimedean copulas, and do tail dependence study of SSE composite index and SESE component index. The results show that the SSE composite index and SESE component index simultaneously have the upper tail dependence and lower tail dependence, and the upper tail dependence coefficient is less than the lower tail dependence coefficient, which is consistent with the real financial market rule.

关键词： Rank Copula Nonparametric Estimation Tail Dependence

早寒武纪清江丝菌牵出硫酸盐还原菌与地球环境协同演化历史

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Science Bulletin 2024年第10期69卷 1486-1494页

作者：崔琳浩朱珂磊李瑞云常超吴来源刘伟傅东静刘沛余邱浩唐国强李秋立 Robert R.Gaines 陶昕王寅李金华张兴亮 State Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an 710069China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Department of Geology Pomona CollegeClaremont CA 91711USA State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial *** reducers are exclusively prokaryotic,phylogenetically diverse,and may have evolved early in Earth’s ***,their origin is elusive and unequivocal fossils are *** we report a new microfossil,Qingjiangonema cambria,from518-million-year-old black shales that yield the Qingjiang *** is a long filamentous form comprising hundreds of cells filled by equimorphic and equidimensional pyrite microcrystals with a light sulfur isotope *** lines of evidence indicate Qingjiangonema was a sulfate-reducing bacterium that exhibits similar patterns of cell organization to filamentous forms within the phylum Desulfobacterota,including the sulfate-reducing Desulfonema and sulfide-oxidizing cable *** analyses confirm separate,independent origins of multicellularity in Desulfonema and in cable *** clock analyses infer that the Desulfobacterota,which encompass a majority of sulfate-reducing taxa,diverged~2.41 billion years ago during the Paleoproterozoic Great Oxygenation Event,while cable bacteria diverged~0.56 billion years ago during or immediately after the Neoproterozoic Oxygenation *** together,we interpret Qingjiangonema as a multicellular sulfate-reducing microfossil and propose that cable bacteria evolved from a multicellular filamentous sulfate-reducing *** infer that the diversification of the Desulfobacterota and the origin of cable bacteria may have been responses to oxygenation events in Earth’s history.

关键词： Cambrian Qingjiangonema Sulfate-reducing bacteria Cable bacteria Qingjiang biota Black shale

Research on the Relationship between CPI and PPI Based on VEC Model

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Open Journal of Statistics 2019年第2期9卷 218-229页

作者： Shijun Li guoqiang tang Duancui Yang Shixue Du School of Science Guilin University of Technology Guilin China

By establishing the VEC model, the relationship between Consumer Price Index (CPI) and Producer Price Index (PPI) is explored by using Johansen cointegration test and impulse response function. The results show that there is a long-term equilibrium cointegration relationship between CPI and PPI. CPI has a certain impact on PPI. PPI also has a certain impact on CPI. PPI has a great impact on itself both in the long-term and short-term. The current CPI will be adversely affected by the previous CPI and the positive impact of the previous PPI. The current PPI will be positively affected by the previous phase of CPI and the previous phase of PPI.

关键词： VEC Model Consumer Price Index Producer Price Index Impulse Response Function

Risk Measurement and Performance Evaluation of Equity Funds Based on ARMA-GARCH Family Model

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Open Journal of Statistics 2020年第2期10卷 325-340页

作者： Jingling Yang guoqiang tang Duancui Yang Jianwen Zhang College of Science GuiLin University of Technology GuiLin China

There are few comprehensive studies on risk measurement and performance evaluation of stock funds in China. This paper uses the ARMA-GARCH family model to analyze the volatility characteristics of equity funds under the t-distribution and Generalized error distribution (GED), and combines CVaR, PM (Second revised sharp ratio) and CVaR-RAROC (Revised RAROC) to comprehensively evaluate equity funds risk and performance. The empirical analysis of five equity funds in China from October 28, 2010 to May 17, 2019 shows that: Comprehensive evaluation of the risk and performance of equity funds can comprehensively and effectively examine the risks and returns of equity funds, helping investors, financial institutions and regulatory agencies to more fully understand the risks and performance of equity funds.

关键词： Equity Funds ARMA-GARCH Family PM CVaR-RAROC

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具有线性趋势的回归信度模型中的估计和检验

应用概率统计 2009年第3期25卷 290-300页

作者：唐国强华东师范大学金融与统计学院上海200241 桂林工学院数理系桂林541004

研究具有线性趋势回归信度模型的参数估计和检验,对该模型的回归系数和随机效应的方差,利用正交变换法得到了它们的极大似然估计,并得到了参数的无偏估计,对随机效应和是否有线性趋势采用似然比检验,得到了似然统计量较好的近似P值,并... 详细信息

研究具有线性趋势回归信度模型的参数估计和检验,对该模型的回归系数和随机效应的方差,利用正交变换法得到了它们的极大似然估计,并得到了参数的无偏估计,对随机效应和是否有线性趋势采用似然比检验,得到了似然统计量较好的近似P值,并对检验的功效进行了模拟研究。

关键词：回归信度模型正交变换似然比检验.

Success Relies on Win-Win Cooperation

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Beijing Review 2012年第38期55卷 14-15页

作者： tang guoqiang chairman of the China National Committee for Pacific Economic Cooperation

The 20th Economic Leaders＇ Meeting of the Asia-Pacific Economic Cooperation （APEC） forum wrapped up on September 9 in Russia＇s Far Eastem city of Vladivostok. With a theme entitled, ＂integrate to grow, innovate to prosper,＂ economic leaders and representatives actively exchanged views on a wide range of issues, including trade and investment liberalization, regional economic integration, strengthening food security and estabfishing reliable supply chains, as well as cooperation to foster innovative growth.

关键词：合作区域经济一体化亚太经合组织 APEC 粮食安全俄罗斯领导人自由化