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中美贸易战前景 ——脱钩或是重新正常化

中美贸易战前景 ——脱钩或是重新正常...

作者： liu zhan 浙江大学

学位级别：硕士

自由主义观点认为,贸易不是零和博弈,而是正和博弈。那么,中美贸易战对中美贸易关系将会产生怎样的影响呢?本文将探讨中美贸易战的前景,未来中美经贸关系的走向,通过文献分析法、案例分析法、对比分析法等从中美两国的角度深入宽泛的分... 详细信息

自由主义观点认为,贸易不是零和博弈,而是正和博弈。那么,中美贸易战对中美贸易关系将会产生怎样的影响呢?本文将探讨中美贸易战的前景,未来中美经贸关系的走向,通过文献分析法、案例分析法、对比分析法等从中美两国的角度深入宽泛的分析贸易战的原因、影响。贸易逆差、中国科技的快速发展以及对美国霸权的威胁引发的贸易战,源于中美两国都希望保持自己的实力和经济增长,这使得妥协变得困难。如果未来中美经贸关系出现脱钩现象,除了中美两国关系将会进一步恶化外,所带来的负面影响不仅仅是对中美两国产生的,其后果将波及全球经济。因此,中美两国需要通过更多的沟通、协商来解决中美经贸关系上的分歧,避免中美贸易关系脱钩。中国需要深化改革,深化开放,营造国际化营商环境,设立国际化规则标准,重启中美经贸关系正常化。

关键词：中美贸易战中美贸易战前景中美经济关系的脱钩中美经济关系重新正常化

原位生长α-Co(OH)2纳米片修饰电极快速检测亚硝酸盐

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现代食品科技 2020年第9期36卷 309-313,236页

作者：刘占广东美味鲜调味食品有限公司广东中山528400

本工作以硝酸钴为前驱体,通过一步电沉积法在玻碳电极表面原位生长氢氧化钴纳米片,构建了电化学传感器,研究了其对NO2-离子的电催化行为,建立了快速测定NO2^-离子的电化学方法。通过扫描电子显微镜(Scanning electron microscope,SEM)... 详细信息

本工作以硝酸钴为前驱体,通过一步电沉积法在玻碳电极表面原位生长氢氧化钴纳米片,构建了电化学传感器,研究了其对NO2-离子的电催化行为,建立了快速测定NO2^-离子的电化学方法。通过扫描电子显微镜(Scanning electron microscope,SEM)、能量散射光谱(Elemental energy spectrum analysis,EDX)和电化学技术对所获得的纳米材料的形貌和性能进行表征,进一步研究该修饰电极快速检测NO2^-离子的电化学行为和电催化机理。结果表明,同一浓度NO2^-离子在不同扫描速度与电流响应间成正比关系,得到Co(OH)2/GCE界面的电化学过程受吸附控制。Co(OH)2/GCE对NO2-离子展现了良好的电催化性能,检测线性范围为1~15 mmol/L,检测限为0.29 mmol/L(S/N=3)。该传感器具有快速制备、催化活性好、易操作以及检测耗时短等特点,适用于亚硝酸盐的现场快速筛查。

关键词：氢氧化钴电化学亚硝酸盐

3D joint inversion of surface and borehole gravity data using zeroth-order minimum entropy regularization

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Applied Geophysics 2021年第2期18卷 131-144,272页

作者： Peng Guo-Min Sun Zhong-Yu liu zhan School of Geosciences China University of Petroleum(East China)Qingdao 266580China Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Surface and borehole gravity data contain complementary ***,the joint inversion of these two data types can help retrieve the real spatial distributions of density *** a sharp boundary exists between an anomalous density body and its surrounding rock,the interface recovered by smooth inversion with Tikhonov regularization is not clear,leading to difficulties in the subsequent geological *** this work,we develop a joint inversion of surface and borehole gravity data using zeroth-order minimum entropy *** method takes advantage of the complementary information from surface and borehole gravity data to enhance the imaging resolution of density *** also produces a focused imaging of bodies through the zeroth-order minimum entropy regularization without requiring a preselection of a proper focusing *** apply the developed joint inversion approach to three diff erent synthetic data *** results show that the focusing inversion with the zeroth-order minimum entropy regularization provides a good description of the true spatial extent of anomalous density ***,the joint focusing inversion reconstructs a more reliable density model with a relatively high resolution when a density body is passed through by one or more boreholes.

关键词： gravity anomaly surface gravity borehole gravity joint inversion zeroth-order minimum entropy regularization

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电磁和地震联合反演研究现状及发展趋势

石油地球物理勘探 2020年第2期55卷 465-474,I0008页

作者：彭国民刘展中国石油大学(华东)地球科学与技术学院山东青岛266580

在勘探地球物理中,不同的地球物理数据通常反映了地下岩石不同的地球物理属性,这些观测数据能够相互补充,从而得到地下构造更可靠的成像结果。电磁勘探和地震勘探是两种物理机制不同的地球物理勘探方法,在油气勘探开发中,仅仅利用地震... 详细信息

在勘探地球物理中,不同的地球物理数据通常反映了地下岩石不同的地球物理属性,这些观测数据能够相互补充,从而得到地下构造更可靠的成像结果。电磁勘探和地震勘探是两种物理机制不同的地球物理勘探方法,在油气勘探开发中,仅仅利用地震数据会存在多解性,电磁勘探作为地震勘探的有效辅助手段,二者联合可更好地为油气勘探开发决策服务。电磁和地震联合反演作为地震和电磁联合勘探的重要定量解释方法,能够降低单一数据反演的多解性,提高电磁和地震资料解释的可靠性。首先概述电磁和地震联合反演的分类,然后评述电磁和地震联合反演的研究现状,最后分析电磁和地震联合反演面临的机遇,并指出其未来的研究方向。

关键词：联合反演电磁地震岩石物理交叉梯度

Development of High-speed Machining Database with Case-based Reasoning

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厦门大学学报（自然科学版） 2002年第S1期41卷 48-49页

作者： WANG Zun-tong, liu zhan-qiang, AI Xing (School of Mechanical Engineering, Shandong University, Jinan 250061, China)

Applying high-speed machining technology in shop floor has many benefits, such as manufacturing more accurate parts with better surface finishes. The selection of the appropriate machining parameters plays a very important role in the implementation of high-speed machining technology. The case-based reasoning is used in the developing of high-speed machining database to overcome the shortage of available high-speed cutting parameters in machining data handbooks and shop floors. The high-speed machining database developed in this paper includes two main components: the machining database and the case-base. The machining database stores the cutting parameters, cutting tool data, work pieces and their materials data, and other relative data, while the case-base stores mainly the successfully solved cases that are problems of work pieces and their machining. The case description and case retrieval methods are described to establish the case-based reasoning high-speed machining database. With the case retrieval method, some succeeded cases similar to the new machining problem can be retrieved from the case-base. The solution of the most matched case is evaluated and modified, and then it is regarded as the proposed solution to the new machining problem. After verification, the problem and its solution are packed up into a new case, and are stored in the case-base for future applications.

关键词： case-based reasoning high-speed machining database case

Spatial and seasonal characterization of net primary productivity and climate variables in southeastern China using MODIS data

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 275-285页

作者： Dai-liang PENG Jing-feng HUANG Alfredo R. HUETE Tai-ming YANG Ping GAO Yan-chun CHEN Hui CHEN Jun LI zhan-yu liu Institute of Agricultural Remote Sensing and Information Application Zhejiang University Hangzhou 310029 China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health Zhejiang University Hangzhou 310029 China Key Laboratory of Agricultural Remote Sensing and Information System of Zhejiang Province Hangzhou 310029 China Department of Soil Water and Environmental Science University of Arizona Tucson AZ 85 721 USA Institute of Anhui Meteorology Hefei 230031 China Institute of Jiangsu Meteorology Nanjing 210008 China Institute of Shandong Meteorology Jinan 250031 China Institute of Fujian Meteorology Fuzhou 350001 China Shanghai Climate Centre Shanghai 200030 China

We developed a sophisticated method to depict the spatial and seasonal characterization of net primary productivity (NPP) and climate variables. The role of climate variability in the seasonal variation of NPP exerts delayed and continuous effects. This study expands on this by mapping the seasonal characterization of NPP and climate variables from space using geographic information system (GIS) technology at the pixel level. Our approach was developed in southeastern China using moderate-resolution imaging spectroradiometer (MODIS) data. The results showed that air temperature,precipitation and sunshine percentage contributed significantly to seasonal variation of NPP. In the northern portion of the study area,a significant positive 32-d lagged correlation was observed between seasonal variation of NPP and climate (P<0.01),and the influences of changing climate on NPP lasted for 48 d or 64 d. In central southeastern China,NPP showed 16-d,48-d,and 96-d lagged correlation with air temperature,precipitation,and sunshine percentage,respectively (P<0.01); the influences of air temperature and precipitation on NPP lasted for 48 d or 64 d,while sunshine influence on NPP only persisted for 16 d. Due to complex topography and vegetation distribution in the southern part of the study region,the spatial patterns of vegetation-climate relationship became complicated and diversiform,especially for precipitation influences on NPP. In the northern part of the study area,all vegetation NPP had an almost similar response to seasonal variation of air temperature except for broad crops. The impacts of seasonal variation of precipitation and sunshine on broad and cereal crop NPP were slightly different from other vegetation NPP.

关键词： Net primary productivity Climate variables Spatial characterization Lagged cross-correlation Moderate-resolution imaging spectroradiometer Geographic information system technology

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法国竞争力集群计划研究

中国科技论坛 2009年第12期 134-139页

作者：刘湛法国阿尔图大学跨学科经济研究中心 ereia59140

自戴高乐主义以来,法国积极谋求世界格局多极化趋势,并以世界重要一极自居,近半个世纪以来是国内外政策也多以此为纲。2005年法国启动了"竞争力集群计划",旨在振兴国家科技和经济,提升法兰西的国际竞争力。本文对该计划的实施背景、进... 详细信息

自戴高乐主义以来,法国积极谋求世界格局多极化趋势,并以世界重要一极自居,近半个世纪以来是国内外政策也多以此为纲。2005年法国启动了"竞争力集群计划",旨在振兴国家科技和经济,提升法兰西的国际竞争力。本文对该计划的实施背景、进展、实例、第一期评估结果与最新动态进行研究。

关键词：法国竞争力集群创新政策

Inhomogenous Dislocation Nucleation Based on Atom Potential in Hexagonal Noncentrosymmetric Crystal Sheet

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Chinese Physics Letters 2010年第1期27卷 186-189页

作者：赵雪川刘小明庄茁柳占立高原 Applied Mechanics Laboratory Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing 100084

By introducing internal degree, the deformation of hexagonal noncentrosymmetric crystal sheet can be described by the revised Cauchy-Born rule based on atomic potential. The instability criterion is deduced to investigate the inhomogeneous dislocation nucleation behavior of the crystal sheet under simple loading. The anisotropic characters of dislocation nucleation under uniaxial tension are studied by using the continuum method associated with the instability criterion. The results show a strong relationship between yield stress and crystal sheet chirality. The results also indicate that the instability criterion has sufficient ability to capture the dislocation nucleation site and expansion. To observe the internal dislocation phenomenon, the prediction of the dislocation nucleation site and expansion domain is illustrated by MD simulations. The developed method is another way to explain the dislocation nucleation phenomenon.

关键词： Chinese climate network complex systems small world community

成人全身麻醉下鼻道手术苏醒期躁动的影响因素分析

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临床耳鼻咽喉头颈外科杂志 2015年第21期29卷 1881-1885页

作者：刘展南阳市中心医院麻醉科河南南阳473000

目的:分析成人全身麻醉下鼻道手术苏醒期躁动(EA)的发生率及影响因素,为临床预防和控制EA提供依据。方法:随机选取并分析2013-02-2015-02期间住院治疗并行全身麻醉下鼻道手术的674例成年患者。依据镇静-躁动评分(SAS)对患者EA进行评定,... 详细信息

目的:分析成人全身麻醉下鼻道手术苏醒期躁动(EA)的发生率及影响因素,为临床预防和控制EA提供依据。方法:随机选取并分析2013-02-2015-02期间住院治疗并行全身麻醉下鼻道手术的674例成年患者。依据镇静-躁动评分(SAS)对患者EA进行评定,并依据是否发生躁动分为对照组(518例)和EA组(156例)。分析人口学及临床相关指标对躁动发生的影响,并进行多元Logistic回归分析。结果:全身麻醉作用下鼻道手术患者EA发生率为23.15%。与对照组相比较,EA组患者在性别、年龄、ASA分级、吸烟史、脑血管病史、术前焦虑、使用咪达唑仑、麻醉方式、术后疼痛、术后镇痛、气管导管、留置尿管、苏醒方式等方面差异有统计学意义(P<0.05);多元Logistic回归结果表明,较轻的年龄、男性、术前焦虑、静吸复合麻醉、术后疼痛、气管插管及留置尿管为全身麻醉下鼻道手术患者EA发生的危险因素,年长者、配合使用咪达唑仑、全凭静脉麻醉、术后镇痛以及自然苏醒为保护性因素。结论:EA是成人全身麻醉下鼻道手术后的常见并发症,并与多种因素相关。临床应将具有以上危险因素的患者作为发生EA的高危群体重点关注,采取有效预防措施,保证患者平稳地度过苏醒期。

关键词：全身麻醉鼻道手术苏醒期躁动影响因素 Logistic回归分析