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动态地理背景下过度饮酒行为的时空特征及影响因素——以广州市中心城区为例

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地球信息科学学报 2024年第8期26卷 1794-1810页

作者：文隽永周素红李双明中山大学地理科学与规划学院广东省公共安全与灾害工程技术研究中心广州市急救医疗指挥中心

过度饮酒的危害是中国乃至全球面临的问题。本研究结合经典理论构建过度饮酒行为与地理环境关系的理论框架，使用广州市急救医疗指挥中心受理的公众急性酒精中毒呼叫记录、手机信令等多源时空数据，探究动态地理背景下过度饮酒行为的时... 详细信息

过度饮酒的危害是中国乃至全球面临的问题。本研究结合经典理论构建过度饮酒行为与地理环境关系的理论框架，使用广州市急救医疗指挥中心受理的公众急性酒精中毒呼叫记录、手机信令等多源时空数据，探究动态地理背景下过度饮酒行为的时空特征及影响因素。结果显示：(1)过度饮酒行为在时间上多发于周末和夜间，在空间上集中于城市商业中心；其空间分布在日间较为均衡，而在夜间较为集聚；(2)过度饮酒行为受酒精可获得性的影响，其与社区的KTV、交通站点密集度正相关。KTV的正向影响在日间主要体现在旧城区，在夜间体现在旧城区、近郊区和开发区，夜间的影响相对明显；交通站点的正向影响主要体现在近郊区，且在日间相对明显；(3)过度饮酒行为也受部分空间失序因素的影响，其与所在社区的土地建成率正相关，但与建筑楼龄、街景脏乱度等关系不显著。土地建成率的正向影响主要体现在新城区的景观风貌核心地区以及城郊结合部的城中村社区，且在日间相对明显；(4)过度饮酒行为与社会失序的关系较为复杂且时空分异性较强，其整体上与社区的外地出生人口比例负相关，与低教育人口比例和住宅租金正相关。(5)按照日间和夜间过度饮酒行为影响因素的聚类，分别划分不同的类型区，可针对这些类型区实施差异化的干预措施，以降低过度饮酒的危害。研究揭示了动态地理背景和较小空间尺度下过度饮酒行为与地理环境的关系，弥补了以往的相关研究对动态地理背景和时空异质性考虑不足、分析尺度较大等局限，相关结果能为酒精政策制定和完善、地区治安和卫生资源配置、城乡空间规划设计和相关健康问题的环境干预措施提供参考。

关键词：健康地理犯罪地理地理加权回归急救数据过度饮酒酒精中毒动态地理背景地理环境时空特征

定向凝固Al_(7)(CoCrFeMnNi)_(93)高熵合金微观组织演化及单晶生长

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稀有金属材料与工程 2024年第6期53卷 1616-1625页

作者：王强力钟宏李斗郑晗煜胡忠武高选乔张文李双明西北工业大学凝固技术国家重点实验室陕西西安710072 西北有色金属研究院陕西西安710016

采用定向凝固技术研究了Al_(7)(CoCrFeMnNi)_(93)高熵合金微观组织的演化规律,以自然竞争生长法制备出胞状和树枝状亚结构单晶体,并研究了亚结构和取向对高熵合金单晶体纳米力学性能的影响。结果表明,Al_(7)(CoCrFeMnNi)_(93)高熵合金... 详细信息

采用定向凝固技术研究了Al_(7)(CoCrFeMnNi)_(93)高熵合金微观组织的演化规律,以自然竞争生长法制备出胞状和树枝状亚结构单晶体,并研究了亚结构和取向对高熵合金单晶体纳米力学性能的影响。结果表明,Al_(7)(CoCrFeMnNi)_(93)高熵合金在定向凝固过程中界面更容易失稳,其平-胞界面转变速率小于1μm/s,胞-枝界面转变速率范围约为2~5μm/s。合金的一次、二次枝晶间距均随着定向凝固速率增加而逐渐减小,并分别与抽拉速率满足指数关系。定向凝固后,该合金枝晶干区域富集Co、Cr和Fe元素,而熔点较低的Mn、Ni和Al元素倾向于富集枝晶间区域。以自然竞争法获得的胞状、树枝状亚结构单晶的取向分别为[214]和[213]。纳米力学性能数据表明偏析行为造成的亚结构对单晶体的弹性模量和硬度影响较小,而晶体取向对单晶体的弹性模量影响较大,对硬度值影响较小。

关键词：定向凝固高熵合金微观组织演化亚结构单晶生长

IFCEM based recognition method for target with interval-overlapped hybrid attributes

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Journal of Systems Engineering and Electronics 2023年第2期34卷 408-421页

作者： GUAN Xin li shuangming SUN Guidong WANG Haibin Naval Aviation University Yantai 264001China Unit 92941 of PLA Huludao 125001China Unit 32801 of PLA Beijing 100082China

When the attributes of unknown targets are not just numerical attributes,but hybrid attributes containing linguistic attributes,the existing recognition methods are not *** addition,it is more difficult to identify the unknown targets densely distributed in the feature space,especially when there is interval overlap between attribute measurements of different target *** address these problems,a novel method based on intuitionistic fuzzy comprehensive evaluation model(IFCEM)is *** numerical attributes,targets in the database are divided into individual classes and overlapping classes,and for linguistic attributes,continuous interval-valued linguistic term set(CIVLTS)is used to describe target characteristic.A cloud modelbased method and an area-based method are proposed to obtain intuitionistic fuzzy decision information of query target on numerical attributes and linguistic attributes *** improved inverse weighted kernel fuzzy c-means(IWK-FCM)algorithm is proposed for solution of attribute weight *** possibility matrix is applied to determine the identity and category of query ***,a case study composed of parameter sensitivity analysis,recognition accuracy *** comparison with other methods,is taken to verify the superiority of the proposed method.

关键词： intuitionistic fuzzy comprehensive evaluation model(IFCEM) interval overlapping cloud model area-based method inverse weighted kernel fuzzy c-means(IWK-FCM)

Combination for Conflicting Interval-Valued Belief Structures with CSUI-DST Method

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Chinese Journal of Electronics 2022年第5期31卷 980-990页

作者： li shuangming GUAN Xin YI Xiao SUN Guidong Naval Aviation University Unit 92941 of PLA Unit 32801 of PLA

Since the basic probability of an intervalvalued belief structure(IBS) is assigned as interval number, its combination becomes difficult. Especially, when dealing with highly conflicting IBSs, most of the existing combination methods may cause counter-intuitive results,which can bring extra heavy computational burden due to nonlinear optimization model, and lose the good property of associativity and commutativity in Dempster-Shafer theory(DST). To address these problems, a novel conflicting IBSs combination method named CSUI(conflict,similarity, uncertainty, intuitionistic fuzzy sets)-DST method is proposed by introducing a similarity measurement to measure the degree of conflict among IBSs, and an uncertainty measurement to measure the degree of discord, non-specificity and fuzziness of IBSs. Considering these two measures at the same time, the weight of each IBS is determined according to the modified reliability degree. From the perspective of intuitionistic fuzzy sets, we propose the weighted average IBSs combination rule by the addition and number multiplication operators. The effectiveness and rationality of this combination method are validated with two numerical examples and its application in target recognition.

关键词： Conflicting IBSs Similarity and uncertainty measure Addition and number multiplication operators Weight

Seaweed pattern formation in the non-axially directional solidification of 2D-like and 3D Al-3 wt.% Mg single crystal

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Journal of Materials Science & Technology 2023年第16期147卷 1-5页

作者： Yumin Wang Bin Yang shuangming li Xin Cao Zhongli liu Hui Xing College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China Inner Mongolia Metal Material Research Institute Yantai 264003China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Shaanxi Key Laboratory of Condensed Matter Structure and PropertiesNorthwestern Polytechnical UniversityXi’an 710129China

*** Microstructures are at the centre of materials science and engineering and play an essential role in determining the in-service mechanical properties of metallic alloys[1–4].Extensive theoretical and experimental investigations have been undertaken to describe and determine solidification microstructures as a function of solidification *** seaweed pattern is one of the most important classes of microstructural patterns[5–7].The characteristic of this pattern is that its extending tips—unlike the behaviour observed in needle-like dendrites—split repeatedly into two or more parts.

关键词： solidification pattern directional

基于MVVM的ReaxFF MD模拟的化学反应数据系统的建立

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科技通报 2024年第1期40卷 1-7,25页

作者：魏财熠夏诏杰李晓霞郑默任春醒李双明沈阳化工大学化学工程学院沈阳110142 中国科学院过程工程研究所多相复杂系统国家重点实验室北京100190 中国科学院大学化学工程学院北京100049

基于反应力场(reactive force field,ReaxFF)的反应分子动力学模拟的结果分析具有挑战性。国际首个ReaxFF MD化学反应分析及可视化工具VARxMD(visulization and analysis of ReaxFF molecular dynamics)可自动生成不同时刻之间完整的化... 详细信息

基于反应力场(reactive force field,ReaxFF)的反应分子动力学模拟的结果分析具有挑战性。国际首个ReaxFF MD化学反应分析及可视化工具VARxMD(visulization and analysis of ReaxFF molecular dynamics)可自动生成不同时刻之间完整的化学反应列表,通过物种检索进一步对反应路径进行分类。但VARxMD目前的反应分析针对的是某一确定条件下单一的ReaxFF MD模拟轨迹,利用VARxMD分析获得一次模拟的完整反应列表需要消耗大量计算资源和时间。本文提出基于数据库来储存VARxMD反应分析结果数据,基于数据库检索进一步分析反应的思路,并采用MVVM(model-view-view model)的系统设计模式、结合渐进式框架***建立了ReaxFF MD模拟的化学反应数据系统ReaxMDDB(reaction database of ReaxFF MD simulation)。系统应用于多个RP-3模型热解和氧化模拟反应数据的结果表明:该系统不仅实现了多个ReaxFF MD模拟的详细反应的统一分析和化学反应的2D分子结构显示,而且可永久保存模拟获得的反应数据集以备后续进一步分析反应机理。ReaxMDDB具有很好的通用性,为认识不同反应模拟所揭示的共性化学反应机理提供了方便的平台。

关键词：反应数据库反应分子动力学化学信息学 MVVM ReaxFF MD

FeMoO_(x)的制备及其催化甘油选择性氧化制丙烯醛/丙酮性能研究

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精细石油化工 2024年第4期41卷 25-31页

作者：苏天月王一雯李双明张思琪于晓君于三三黄桂珍沈阳化工大学化学工程学院辽宁沈阳110142

采用喷雾干燥法快速制备了FeMoO_(x)复合金属氧化物。考察了铁/钼(原子比)对FeMoO_(x)晶相组成、形貌、酸性位点等结构的影响,同时以甘油选择性氧化为探针反应考察了FeMoO_(x)的催化性能。结果表明:当n(Fe)∶n(Mo)=1∶1.5时制备的FeMoO_... 详细信息

采用喷雾干燥法快速制备了FeMoO_(x)复合金属氧化物。考察了铁/钼(原子比)对FeMoO_(x)晶相组成、形貌、酸性位点等结构的影响,同时以甘油选择性氧化为探针反应考察了FeMoO_(x)的催化性能。结果表明:当n(Fe)∶n(Mo)=1∶1.5时制备的FeMoO_(x)为100%的Fe_(2)(MoO_(4))_(3)晶相,并且呈现出特殊的类核桃形貌。含有最多的Bronsted酸位点(B/(B+L)值为0.23),有利于在甘油中心—OH处发生质子化,进而提升了FeMoO_(x)的催化性能。该试样在催化甘油选择性氧化反应中表现出最佳的性能,在催化反应温度为260℃时,甘油转化率为83.7%,丙烯醛和丙酮的选择性分别为43.5%和18.4%。

关键词：铁钼复合金属氧化物喷雾干燥法甘油选择性氧化

liquid concentration distribution and planar interface instability at an abruptly changing pulling velocity in directional solidification

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Science China(Technological Sciences) 2007年第1期50卷 118-126页

作者： li shuangming FU HengZhi State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

liquid concentration distribution is seriously affected by an abruptly changing pulling velocity under directional solidification. Theoretical and numerical investi-gations indicate that at the pulling velocity jumping from V0 to V, the solidification system does not achieve the pulling velocity V immediately, and it goes through a non-steady-state transition zone. As the pulling velocity abruptly increases (V/V0 > 1), interface liquid concentration firstly increases to the maximum and then de-creases to the steady-state value. The magnitude of interface liquid concentration at the beginning increases with V/V0, the initial pulling velocity V0 and the tem-perature gradient GL in the liquid. At the same time, solute diffusion length reduces with V/V0 and GL. In contrast, the minimum of interface liquid concentration falls with V/V0 at the pulling velocity decreasing abruptly. As the interface liquid con-centration enriched at V/V0 > 1 is more than the value required for the planar inter-face to keep stable, the solid/liquid interface may become unstable. The analytical results are in agreement with the numerical calculation results of Al-2%Cu alloy.

关键词： directional solidification abruptly changing velocity concentration distribution Al-Cu alloy

Effect of sample diameter on primary and secondary dendrite arm spacings during directional solidification of Pb-26wt.%Bi hypo-peritectic alloy

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Rare Metals 2011年第4期30卷 424-431页

作者： HU Xiaowu YAN Hong CHEN Wenjing li shuangming FU Hengzhi School of Mechanical-Electrical Engineering Nanchang University Nanchang 330031 China Department of Applied Physics Northwestern P olytechnical University Xi＇an 710072 China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

The microstructure scales of dendrites, such as primary and secondary dendrite arm spacings, control the segregation profiles and the formation of secondary phases within interdendritic regions, which determine the properties of solidified structures. Investigations on primary and secondary dendrite arm spacings of primary a-phase during directionally solidified Pb-26wt%Bi hypo-peritectic alloy were carried out in this research, and systematic studies were conducted using cylindrical samples with different diameters （Ф = 1.8 and 7.0 mm） in order to analyze the effects of sample diameter on the primary and secondary dendrite arm spacings. In this work, the dependence of dendrite arm spacings on growth velocity was established. In addition, the experimental data concerning the primary and secondary dendrite ann spacings were compared with the main predictive dendritic models from the literatures. A comparison between experimental results for dendrite arm spacings of the 1.8-mm-diameter sample and 7.0-ram-diameter sample was also conducted.

关键词： lead bismuth alloys dendrite arm spacing directional solidification dendrites