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中国玉米自给率时空格局变化驱动因素及区域异质性分析

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玉米科学 2024年第7期32卷 118-126页

作者：曹炎杨艳涛王国刚中国农业科学院农业经济与发展研究所北京100081

测算1999-2022年中国及各区域的玉米自给率,分析其时空格局及其变化趋势,通过空间杜宾模型分析中国玉米自给率的驱动因素,并对各区域进行异质性检验。研究表明,1999-2022年中国玉米自给率呈波动式下降趋势,阶段性、区域性特征明显。技... 详细信息

测算1999-2022年中国及各区域的玉米自给率,分析其时空格局及其变化趋势,通过空间杜宾模型分析中国玉米自给率的驱动因素,并对各区域进行异质性检验。研究表明,1999-2022年中国玉米自给率呈波动式下降趋势,阶段性、区域性特征明显。技术因素是影响中国玉米自给率变化的主要因素。东北、华中、西南、西北地区生产因素影响显著,经济因素对华东、华南地区影响显著;政策因素对6个区域玉米自给率时空格局变化影响较大,技术因素影响最显著。提出关注玉米自给率的空间互动效应、加大科技投入、各地区有针对性的提升玉米单位面积产量和降低成本等相关政策建议。

关键词：玉米自给率空间杜宾模型

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从资产负债表机理看信用货币创造的内在逻辑

贵州财经大学学报 2024年第4期 21-37页

作者：王国刚方明浩潘登中国人民大学北京100872 上海财经大学上海200433 上海市人民政府发展研究中心上海200003

“存款创造贷款、贷款创造存款”是主流货币理论的重要基础。英国学者乔西·瑞安-柯林斯等人和中国学者孙国峰等人认为,“存款创造贷款”的原理存在根本性错误,用于存款的货币均为贷款的产物,因此,不是“存款创造贷款”而是“贷款创造... 详细信息

“存款创造贷款、贷款创造存款”是主流货币理论的重要基础。英国学者乔西·瑞安-柯林斯等人和中国学者孙国峰等人认为,“存款创造贷款”的原理存在根本性错误,用于存款的货币均为贷款的产物,因此,不是“存款创造贷款”而是“贷款创造存款”,银行可以无限地凭空创造贷款。本文对这一认识寻根溯源,指出其中的偏颇之处。“贷款创造存款”的认识,从麦克鲁德算起已有140多年的历史,但它并不符合信用货币创造和资产负债表复式记账的内在机理。商业银行贷款以有款可贷为前提;在无款可贷条件下,贷款合同只是一纸空文。在实施贷款行为中,资金应从商业银行在央行的存款账户划到客户在商业银行的存款账户。从资金流程角度看,这是“存款创造存款”过程。从央行资产负债表看,不论是“发行货币”还是收取“存准”、吸收超额存款准备金都是资金来源的重要渠道,有了资金来源,才能有效地开展贷款、贴现、公开市场操作等“资金使用”,这一切操作都建立在真实资金的基础上,并非无中生有的“贷款创造存款”。“存款创造贷款”与“贷款创造存款”之争在理论逻辑中无解,要解开这一死结,需要回到历史起点。人民币最初入市是与边币和旧币的兑换,初始信用货币并非来自贷款;银行券的问世建立在贵金属货币准备的基础上,并非来自贷款。如果银行可以凭空创造贷款,则不存在美国硅谷银行破产事件,也不存在2008年美国金融危机,同时,利率理论、商业银行经营管理理论、资产负债表理论、货币政策理论、汇率理论等均将失效。

关键词：信用货币创造资产负债表存款贷款

Numerical Investigation on the Effects of Re-Organized Shock Waves on the Flow Separation for a Highly-Loaded Transonic Compressor Cascade

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Journal of Thermal Science 2012年第1期21卷 13-20页

作者： wang Yan gang guo Rui Zhao Longbo Ren Siyuan School of Power ＆ Energy Northwestern Polytechincal University

This paper presents a detailed numerical investigation of the influence of re-organized shock waves on the flow separation for a highly-loaded transonic compressor cascade. The boundary layer suction (BLS) was used to control the location and strength of shock waves, with the aspirated slot locating at 49% chord, where is just downstream of the impingement point of shock wave at the leading edge. The numerical simulation is based on NUMECA, a commercial software, where the cell-centered control volume approach with third-order spatial accuracy is used to solve the 3-D Reynolds-averaged Navier-Stokes equations under the Cartesian coordinate system. Several conclusions can be made through the observation of the numerical results. (1) Multiple shock waves in cascade passage leaded the velocity deficits of boundary layer on suction surface downstream of shock wave, resulting in seriously separated flow on the suction side of blade, especially when the front shock wave is much stronger than the rest of the shocks. (2) BLS with small mass flow rate can not effectively improve the boundary layer. When the impingement point of oblique shock wave coming from cascade leading edge is bled to downstream of the passage shock wave by BLS, the boundary layer flow is greatly improved. However, if the BLS mass flow rate exceeds a critical value (1.2%), the boundary layer downstream of shock wave would separate from suction surface. (3) At the blade mid-span, the aerodynamic performance of compressor blade is improved as BLS mass flow rate increases. The optimum BLS is about 1.2%. Compared with the baseline case, the BLS with flow rate of 1.2% increases the total pressure recovery coefficient by 12%, and decreases diffusion factor by 18% and deviation angle to 7 ° while keeping the pressure rise constant. (4) The three dimensional flow structure of the compressor cascade ranged from 25% span to 75% span was improved greatly with the 1.2% BLS flow rate. However it could not control th

关键词： suction flow shock wave boundary layer interaction effects

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构建强大金融机构,助力金融强国建设

金融论坛 2024年第4期 3-10页

作者：李扬王国刚周诚君曹远征刘俏卢永真张杰中国社会科学院学部国家金融与发展实验室中国人民大学中国人民银行金融研究所所中银国际研究公司北京大学光华管理学院中国工商银行

2024年1月16日,习近平总书记在省部级主要领导干部推动金融高质量发展专题研讨班开班式上发表重要讲话,深刻阐释了金融强国建设的丰富内涵,指出强大的金融机构是金融强国应当具备的六大关键核心金融要素之一。强大的金融机构是金融强国... 详细信息

2024年1月16日,习近平总书记在省部级主要领导干部推动金融高质量发展专题研讨班开班式上发表重要讲话,深刻阐释了金融强国建设的丰富内涵,指出强大的金融机构是金融强国应当具备的六大关键核心金融要素之一。强大的金融机构是金融强国建设的重要微观基础,既要以所在经济体强大的经济基础和综合国力作为保障和支持,还应具备韧性强、进化快、布局广、影响力大等关键特征。为认真学习贯彻习近平总书记关于金融强国的重要论述,深刻把握建设金融强国的精髓要义和实践要求,中国工商银行组织召开“建设强大金融机构”专家学者座谈会,与会专家从理论与实践、国内与国际、历史与现实等多个维度进行了讨论交流,现将有关观点刊登如下,以飨读者。

关键词：金融机构中国工商银行金融强国讨论交流理论与实践金融要素关键特征微观基础

SNAR新型除酸脱硝技术在催化裂化装置上的工业试验探究

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现代化工 2024年第10期44卷 216-220页

作者：王振南刘甜甜王国刚张海超张欣王海青李世鹏青岛惠城环保科技集团股份有限公司山东青岛266000

某公司催化裂化装置因生产加工的减压渣油中硫含量较高,造成烟尘中SO_(3)含量比较高,所形成的H_(2)SO_(4)气溶胶导致烟气出现蓝烟拖尾状况。采用SNAR清洁型选择性非氨基还原除酸脱硝技术进行试验,结果表明,SNAR生产工艺在高温段下NO_(x... 详细信息

某公司催化裂化装置因生产加工的减压渣油中硫含量较高,造成烟尘中SO_(3)含量比较高,所形成的H_(2)SO_(4)气溶胶导致烟气出现蓝烟拖尾状况。采用SNAR清洁型选择性非氨基还原除酸脱硝技术进行试验,结果表明,SNAR生产工艺在高温段下NO_(x)的脱除率达80%~95%,而且无氨逃逸存在,SO_(3)的总体脱除率达60%~80%,蓝烟拖尾状况有明显改善,同时未对生产线设备产生腐蚀等不良影响,为催化裂化设备安全运行增加了经济收益和环境效益。

关键词：催化裂化烟气 SO_(3) SNAR技术

Vacancy defect MoSeTe embedded in N and F co-doped carbon skeleton for high performance sodium ion batteries and hybrid capacitors

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Journal of Energy Chemistry 2024年第3期90卷 652-664,I0014页

作者： Dehui Yang Wentao guo Fei guo Jiaming Zhu gang wang Hui wang Guanghui Yuan Shenghua Ma Beibei wang State Key Laboratory of Photon-Technology in Western China Energy International Collaborative Center on Photoelectric Technology and Nano Functional MaterialsInstitute of Photonics&Photon-TechnologyNorthwest UniversityXi’an 710127ShannxiChina Key Laboratory of Synthetic and Natural Functional Molecule Chemistry(Ministry of Education) College of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127ShannxiChina School of Chemistry and Chemical Engineering Ankang Research Centre of New Nano-materials Science and TechnologyShaanxi University Innovation Research Institute of Advanced Energy Storage Materials and Battery Technology for Future IndustrializationAnkang UniversityAnkang 725000ShannxiChina

Sodium-ion batteries(SIBs) and hybrid capacitors(SIHCs) have garnered significant attention in energy storage due to their inherent advantages,including high energy density,cost-effectiveness,and enhanced ***,developing high-performance anode materials to improve sodium storage performa nce still remains a major ***,a facile one-pot method has been developed to fabricate a hybrid of MoSeTe nanosheets implanted within the N,F co-doped honeycomb carbon skeleton(MoSeTe/N,F@C).Experimental results demonstrate that the incorporation of large-sized Te atoms into MoSeTe nanosheets enlarges the layer spacing and creates abundant anion vacancies,which effectively facilitate the insertion/extraction of Na^(+) and provide numerous ion adsorption sites for rapid surface capacitive ***,the heteroatoms N,F co-doped honeycomb carbon skeleton with a highly conductive network can restrain the volume expansion and boost reaction kinetics within the *** anticipated,the MoSeTe/N,F@C anode exhibits high reversible capacities along with exceptional cycle *** coupled with Na_(3)V_(2)(PO_(4))_(3)@C(NVPF@C) to form SIB full cells,the anode delivers a reversible specific capacity of 126 mA h g^(-1) after 100 cycles at 0.1 A g^(-1).Furthermore,when combined with AC to form SIHC full cells,the anode demonstrates excellent cycling stability with a reversible specific capacity of50 mA h g^(-1) keeping over 3700 cycles at 1.0 A g^(-1).In situ XRD,ex situ TEM characterization,and theoretical calculations(DFT) further confirm the reversibility of sodium storage in MoSeTe/N,F@C anode materials during electrochemical reactions,highlighting their potential for widespread practical *** work provides new insights into the promising utilization of advanced transition metal dichalcogenides as anode materials for Na^(+)-based energy storage devices.

关键词： MoSeTe N F co-doped honeycomb carbon skeleton Sodium-ion batteries Sodium-ion hybrid capacitor

Image Demosaicing by Non-local Similarity and Local Correlation 11th

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Image Demosaicing by Non-local Similarity and Local Correlat...

基于Res2Net-RetinaNet的活性污泥指示性微生物目标检测

2012 IEEE 11th International Conference on Signal Processing(ICSP 2012)

作者： wang guo-gang Zhu Xiu-chang Gan Zong-liang Province Key Lab on Image Processing and Image Communication Nanjing University of Posts and Telecommunications

ISBN: (纸本)9781467321969

Conventional single-chip digital cameras use color filter arrays（CFA） to sample different spectral components. Image demosaicing is a problem of interpolating these data to complete red, green, and blue values for each image pixel, to produce an RGB image. Many color demosaicing（CDM） methods assume that the high local spatial redundancy exists among the color samples. Such an assumption, however, may be fail for images with high color saturation and sharp color transitions. This paper presents an adaptive demosaicing algorithm by exploiting both the non-local similarity and the local correlation（NLS-LC） in the color filter array image. First, the most flattest nonlocal image patches are searched in the searching window centered on the estimated pixel. Second, the patch, which is the most similar to the current patch, is selected among the most smoothest nonlocal patches. Third, according to the similar degree and the local correlation degree, the obtained nonlocal image patch and the current patch are adaptively chosen to estimate the missing color samples. Experimental results indicate that the proposed method exhibits superior performance over many state-of-the-art color interpolation methods.

关键词： image demosaicing image interpolation local correlation non-local similarity

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化工自动化及仪表 2024年第5期51卷 785-795页

作者：赵立杰鲁茜黄明忠王国刚沈阳化工大学信息工程学院

活性污泥中原生动物、后生动物等指示性微生物是污水处理运行调控的重要指标。针对活性污泥微生物不同种类之间,小目标类微生物体型较小、微生物个体颜色背景和图像颜色背景相似的现象,提出基于Res2Net-RetinaNet的活性污泥指示性微生... 详细信息

活性污泥中原生动物、后生动物等指示性微生物是污水处理运行调控的重要指标。针对活性污泥微生物不同种类之间,小目标类微生物体型较小、微生物个体颜色背景和图像颜色背景相似的现象,提出基于Res2Net-RetinaNet的活性污泥指示性微生物检测方法。Res2Net-RetinaNet模型采用精度更高的新维度残差块Res2Net模块捕获原有特征的丰富信息。在主干网络输出的第1层引入通道和空间注意力机制CBAM,进一步帮助浅层特征信息在网络中流动。最后,在特征融合模块中引入深度超参数化卷积(Do-Conv),在不增加计算量的前提下持续加快模型的收敛。将所提方法应用于某污水厂采集数据中进行实验,结果表明:所提方法与Fast R-CNN、SSD、YOLOv3、YOLOv4、FCOS、CenterNet及RetinaNet等目标检测模型相比,检测精度最高(92.8%),相对于原始RetinaNet目标检测算法精度提升4.97%。

关键词： Res2Net-RetinaNet 污水处理微生物目标检测 Res2Net模块 CBAM注意力机制深度超参数化卷积

Effect of cerium on microstructure,texture and properties of ultrahigh-purity copper

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Journal of Rare Earths 2024年第1期42卷 220-227,I0008页

作者： Yunxiao Hua Haitao Liu Kexing Song Jiangwei wang Yin'gang guo Jing Tian Huiwen guo Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang471023China Henan Academy of Sciences Zhengzhou450000China Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Henan Zhongyuan Gold Smelter Co. Ltd.Sanmenxia472100China Chinalco Luoyang Copper Processing Co. Ltd.Luoyang471039China

The effects of Ce addition(310 ppm and 1500 ppm)on the microstructure,texture and properties of ultrahigh-purity copper(99.99999%)were systematically studied using scanning electron microscopy(SEM),transmission electron microscopy(TEM)and electron backscattered diffraction(EBSD)analyses,combined with the microhardness and conductivity *** the microstructure of the as-cast and as-extruded samples,the addition of Ce refines the grain size of the ultrahigh-purity copper and the refinement effect of 310Ce alloy is greater than that of 1500Ce *** is due to the stronger compone nt supercooling and the accele rated recrystallization caused by lower Ce co *** addition,Ce can react with Cu to form the Cu-Ce eutectic phases,which are deformable during the hot ***,the added Ce can weaken the texture,showing a variation of brass recrystallization(BR),rotated cube,copper and S texture components,which depends on the recrystallization,the particle stimulated nucleation(PSN)as well as the stacking fault energy(SFE).Most remarkably,the introduction of Ce enhances the hardness of the ultrahigh-purity copper without obviously reducing its *** major{111}orientations and the stress distributions are responsible for such a superior conductivity of the Ce-containing alloys.

关键词： Ce addition Grain refinement Texture Conductivity Ultrahigh-purity copper Rare earths