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Numerical investigation of impinging jet ventilation in ICUs:Is thermal stratification a problem?

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Building Simulation 2023年第7期16卷 1173-1185页

作者： Lei Wang Zhiqiang Wang Sirui zhu zhe zhu Tao Jin Jianjian Wei Institute of Refrigeration and Cryogenics/Key Laboratory of Refrigeration and Cryogenic Technology of zhejiang Province Zhejiang UniversityHangzhouChina Center for Balance Architecture Zhejiang UniversityHangzhouChina The Architectural Design&Research Institute of zhejiang University Co LtdHangzhouChina zhejiang Modern Architectural Design and Research Institute Co LtdHangzhouChina

Intensive care units(ICUs)are the high incidence sites of hospital-acquired infections,where impinging jet ventilation(IJV)shows great *** stratification of IJV and its effect on contaminants distribution were systematically investigated in this *** changing the setting of heat source or the air change rates,the main driving force of supply airflow can be transformed between thermal buoyancy and inertial force,which can be quantitatively described by the dimensionless buoyant jet length scale(l_(m)^(-)).For the investigated air change rates,namely 2 ACH to 12 ACH,l_(m)^(-)varies between 0.20 and *** thermal buoyancy plays a dominant role in the movement of the horizontally exhaled airflow by the infector under low air change rate,where the temperature gradient is up to 2.45℃/*** flow center remains close to the breathing zone of the susceptible ahead,resulting into the highest exposure risk(6.6‰for 10-μm particles).With higher heat flux of four PC monitors(from 0 W to 125.85 W for each monitor),the temperature gradient in ICU rises from 0.22℃/m to 1.02℃/m;however,the average normalized concentration of gaseous contaminants in the occupied zone is reduced from 0.81 to 0.37,because their thermal plumes are also able to carry containments around them to the ceiling-level *** the air change rate was increased to 8 ACH(l_(m)^(-)=1.56),high momentum weakened the thermal stratification by reducing the temperature gradient to 0.37℃/m and exhaled flow readily rose above the breathing zone;the intake fraction of susceptible patient located in front of the infector for 10-μm particles reduces to 0.8‰.This study proved the potential application of IJV in ICUs and provides theoretical guidance for its appropriate design.

关键词： impinging jet ventilation heat sources air change rates respiratory particles lock-up phenomenon

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大语言模型在区域国别研究教学中的应用探索

当代教研论丛 2025年第1期11卷 43-47页

作者：朱殿勇李赫哈尔滨工程大学外国语学院黑龙江哈尔滨150001

教学是区域国别研究人才培养的重要环节之一,在人工智能飞速发展的时代,如何利用大语言模型赋能区域国别研究教学工作是一项不可回避的重要课题。文章立足于区域国别研究教学的特征,从学科需求和技术方法双维度探讨大语言模型赋能教学... 详细信息

教学是区域国别研究人才培养的重要环节之一,在人工智能飞速发展的时代,如何利用大语言模型赋能区域国别研究教学工作是一项不可回避的重要课题。文章立足于区域国别研究教学的特征,从学科需求和技术方法双维度探讨大语言模型赋能教学的融合框架,系统探究多语种文献整合、跨文化情境模拟与批判性思维培养等关键环节,并提出数据集准备、知识库构建、模型微调及多模态应用等核心路径,为大语言模型赋能区域国别研究提供思路与理论借鉴。

关键词：大语言模型区域国别研究教学应用思路探索

Cyclic behavior test of a new double-arch steel gate

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Journal of zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1731-1739页

作者： LUO Yao-zhi zhu Shi-zhe CHEN Xi Space Structures Research Center Zhejiang University Hangzhou 310027 China School of Landscape Architecture and Art Zhejiang Forestry University Hangzhou 311300 China

A new double-arch structure for the gate used as tidal barrage and sluice was adopted in Caoe River Dam in China. It was a spatial structure made up of the right arch, the invert arch, the chord, etc., and was designed to bear bilateral loads. To research the cyclic behavior of the new double-arch structure, a scale-model cyclic test was conducted. First, the test setup and test method were presented in detail, and according to the test results, the cyclic behavior and failure characteristics of this structure were discussed. Then by analyzing the test cyclic envelope curve, it was found the curve was divided into three stages: the elastic stage, the local plastic stage and the failure stage at the local yield point and structural yield point. The gate model has local yield strength and structural yield strength, with both their values being bigger than that of the designing load. Therefore, the gate is safe enough for the projects. At last, dynamic property of the gate was analyzed considering additional mass of the water. It was found that the tidal bore shock would not cause resonance vibration of the gate.

关键词： Double-arch steel gate Cyclic behavior test Cyclic envelope curve Dynamic property

Implementation procedure for the generalized moving Preisach model based on a first order reversal curve diagram

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Rare Metals 2009年第4期28卷 355-360页

作者： HAN yong zhu Jie State Key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

First order reversal curves （FORC） of nanocomposite Nd2Fe14B/Fe3B magnetic materials were measured to attain a FORC diagram, which characterizes reversible magnetization, irreversible magnetization, and magnetic interactions in a hysteresis system. Then, generalized mov- ing Preisach model （GMPM） was implemented based on the FORC diagram. Reversible and irreversible magnetizations shown in FORCs and a FORC diagram were used as an input of GMPM. Coupling interaction between reversible and irreversible magnetizations was added when calculating reversible magnetization. Meanwhile, irreversible magnetic moments＇ interaction was approximately represented by mean field interaction. The result shows that the simulated main curves mostly coincide with the experimental curves.

关键词： FORC diagram Preisach model reversible magnetization irreversible magnetization magnetic interactions

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面向高反光表面的结构光面形测量方法

中国光学(中英文) 2025年第1期18卷 42-52页

作者：汪运郭建英梁浚哲朱峰陈光希任茂栋梁晋西安交通大学机械工程学院机械制造系统工程国家重点实验室陕西西安710049 西安交通大学微电子学院陕西西安710049 新拓三维技术(深圳)有限公司创新实验室广东深圳518060

高反光表面复杂的反射性质会使面结构光测量时出现过度曝光和曝光不足的问题。为完整准确地重建被测表面,本文提出一种能根据被测表面反射强度预测曝光时间的多重曝光方法。首先,通过投射一系列不同曝光时间下的均匀灰度图像获得成像系... 详细信息

高反光表面复杂的反射性质会使面结构光测量时出现过度曝光和曝光不足的问题。为完整准确地重建被测表面,本文提出一种能根据被测表面反射强度预测曝光时间的多重曝光方法。首先,通过投射一系列不同曝光时间下的均匀灰度图像获得成像系统的相机响应曲线,同时计算得到能反映被测表面反射强度的辐照度图像。然后,通过模糊C均值聚类方法,自适应分割目标不同辐照度区域并获得各区域的中心辐照度,利用相机响应曲线预测不同反射区域的最优曝光时间。最后,结合多重曝光融合算法实现对高反光表面的三维重建。实验结果显示,所提方法能同时重建铝合金表面的强烈反光区域和过暗区域,重建误差小于0.5 mm,最大偏差降低了74.78%,标准偏差降低了48.96%。上述结果表明,所提方法能根据区域反射特性准确预测曝光时间,有效克服区域过曝和区域过暗带来的相位缺失和相位失真问题,完整准确地重建了高反光表面的不同反射区域。

关键词：高反光表面结构光多重曝光辐照度聚类分割

A FAMILY OF THE LOCAL CONVERGENCE OF THE IMPROVED SECANT METHODS FOR NONLINEAR EQUALITY CONSTRAINED OPTIMIZATION SUBJECT TO BOUNDS ON VARIABLES

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Journal of Systems Science & Complexity 2014年第2期27卷 307-326页

作者： ZHANG yong zhu Detong School of Mathematics and Physics Changzhou University Mathematics and Science College Shanghai Normal University

This paper studies a family of the local convergence of the improved secant methods for solving the nonlinear equality constrained optimization subject to bounds on variables. The Hessian of the Lagrangian is approximated using the DFP or the BFGS secant updates. The improved secant methods are used to generate a search direction. Combining with a suitable step size, each iterate switches to trial step of strict interior feasibility. When the Hessian is only positive definite in an affine null subspace, one shows that the algorithms generate the sequences converging q-linearly and two-step q-superlinearly. Yhrthermore, under some suitable assumptions, some sequences generated by the algorithms converge locally one-step q-superlinearly. Finally, some numerical results are presented to illustrate the effectiveness of the proposed algorithms.

关键词： Affine scaling local convergence secant methods second order correction.

基于人地系统视角耕地利用转型过程及其驱动因素分析——以黑龙江省齐齐哈尔市为例

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自然资源学报 2025年第2期40卷 350-366页

作者：孙心怡王介勇朱西存董雨晴林旭山东农业大学资源与环境学院中国科学院地理科学与资源研究所

快速工业化城镇化发展促使黑土耕地利用方式和程度发生显著变化，深刻影响黑土地资源可持续利用状态。基于人地系统视角构建耕地利用转型分析框架，以齐齐哈尔市为案例区，采用突变级数模型定量分析1995—2020年耕地利用过程及其关键转... 详细信息

快速工业化城镇化发展促使黑土耕地利用方式和程度发生显著变化，深刻影响黑土地资源可持续利用状态。基于人地系统视角构建耕地利用转型分析框架，以齐齐哈尔市为案例区，采用突变级数模型定量分析1995—2020年耕地利用过程及其关键转折点，解析不同转型阶段的主要驱动因素。结果表明：（1）1995—2020年耕地利用系统状态评价值波动上升，集中在0.35～0.45之间，说明齐齐哈尔市耕地利用系统存在不同的利用状态阶段，处于转型变化过程中；（2）以2003年、2015年为转折点，研究区耕地利用方式经历了粗放式开发利用、高强度集约利用、保护可持续利用的转变过程，其功能实现了粮食从“自给自足”（1995—2002年）向“商粮外调”（2003—2014年）再向“绿色转型”（2015—2020年）升级，耕地利用经历了两次转型过程；（3）1995—2020年研究区耕地利用由第一阶段向第二阶段转型主要受要素投入和政策调控等关键因素驱动，第二阶段向第三阶段主要是市场需求、政策调控和科技进步等因素共同作用促使转型。建议继续加强黑土地保护利用力度，统筹黑土区要素资源配置，优化区域耕地利用结构，促进黑土耕地功能升级，夯实保障国家粮食安全和区域农业农村可持续发展基石。

关键词：人地系统耕地利用转型突变级数模型黑土区

An unexpected approach to enhance specific surface area and mesopore amount of polyaniline by Zn doping

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Rare Metals 2024年第9期43卷 4585-4594页

作者： Zhi-Da zhu Yu-zhe Han Xiao-Bi Jing School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Poly-p-anisidine could be easily fabricated via the oxidative polymerization reaction of p-anisidine using H_(2)O_(2)as the green *** was unexpectedly found that zinc doping could significantly improve the adsorption ability of the material versus heavy metals such as Pb,Cu,Pd,Ag and *** of nitrogen adsorption–desorption experiments demonstrated that Zn doping could enhance the specific surface area and mesopore amount of the prepared material,which might facilitate its absorption to *** work not only provides a novel material for the treatment of heavy metal-polluted water but also leads to a nice mesoporous catalyst support for environment protection and organic synthesis,*** Zn-doped poly-panisidine can be employed as the catalyst support to prepare Cu@PANI-OMe/Zn or Pd@PANI-OMe/Zn for the oxidative degradation reaction of phenol or Suzuki–Miyaura coupling reactions,*** discloses a new strategy for fabricating the mesoporous polyaniline materials with profound application potential.

关键词： Surfaces Porous materials Rare metal concentration Adsorption Catalysis

面向SDG11的城市社区可持续性评估——以长沙市为例

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热带地理 2025年第1期45卷 113-127页

作者：秦书茜张楠朱佩娟张勇张趁中南大学建筑与艺术学院长沙410075 湖南师范大学地理科学学院长沙410081 湖南思达源规划咨询研究有限公司长沙410114

在执行和落实联合国可持续发展目标(SDGs)面临现实挑战的背景下,研究制定针对各项目标的本土化评估指标体系,对不同尺度可持续发展现状监测、问题诊断、对策制定等具有重要意义。文章基于可持续发展“经济-社会-环境”三维理论框架,解... 详细信息

在执行和落实联合国可持续发展目标(SDGs)面临现实挑战的背景下,研究制定针对各项目标的本土化评估指标体系,对不同尺度可持续发展现状监测、问题诊断、对策制定等具有重要意义。文章基于可持续发展“经济-社会-环境”三维理论框架,解构可持续发展目标11 (SDG11)在社区尺度的内涵,构建包含7项目标、13项指标的城市社区可持续性评估指标体系,并以长沙市建成区602个样本社区为例,利用多源大数据,开展社区可持续性综合评估及社区“经济-社会-环境”系统耦合协调度评估。结果表明:1) 2010—2020年,长沙市社区可持续发展目标实现度处于“比较接近”区间,并由高到低呈“核心―边缘”空间分布特征;2) 7项目标中,住房保障、防灾减灾和环境治理目标进展顺利,公共交通和遗产保护目标提升显著,公共空间目标缓慢提升,规划管理目标不够理想;3)结合社区“经济-社会-环境”系统耦合协调度评估结果,将样本社区划分为协调发展、过渡发展和失调衰退3种类型,叠加核心区、中心城区和近郊区分区结果,提出差异化治理路径;4)评估指标体系效度较高,后续需借助大量实证案例进一步完善。

关键词：城市社区可持续性 “经济-社会-环境” 可持续发展目标11(SDG11) 社区治理长沙