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Journal of Applied Mathematics and Physics 2024年第6期12卷 2333-2345页

作者： changzhong chen Mingfei chen Wenliang Yu School of Mechanical Engineering Guizhou University Guiyang China

In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL.

关键词： Isogeometric Analysis Sound Transmission Loss Double-Plate System Functionally Graded Materials Acoustic Structure Coupling

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基于个体记忆和高斯扰动的自适应灰狼算法

四川轻化工大学学报（自然科学版） 2024年第2期37卷 64-72页

作者：陈朗陈昌忠刘鑫四川轻化工大学自动化与信息工程学院四川宜宾644000 人工智能四川省重点实验室四川宜宾644000

针对传统灰狼算法在求解复杂优化问题时易陷入局部最优和收敛速度慢等问题,提出一种基于个体记忆和高斯扰动的自适应灰狼算法(NGWO)。首先,引入一个非线性控制参数,以平衡算法中全局探索与局部开发能力。其次,为了加快算法的收敛速度和... 详细信息

针对传统灰狼算法在求解复杂优化问题时易陷入局部最优和收敛速度慢等问题,提出一种基于个体记忆和高斯扰动的自适应灰狼算法(NGWO)。首先,引入一个非线性控制参数,以平衡算法中全局探索与局部开发能力。其次,为了加快算法的收敛速度和提高收敛精度,提出了一种拥有个体记忆的自适应位置更新公式。最后,通过结合贪心算法与自适应高斯扰动方法,增强了本算法跳出局部最优的能力。通过基准函数的测试,并与其他优化算法和改进算法进行对比,结果表明NGWO具有更精确的解和更高的收敛速度。

关键词：灰狼算法非线性控制参数自适应高斯扰动个体记忆

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Relief of Residual Stresses in 800 MPa Grade High Strength Steel Weldments by Explosion Treatment and its Effect on Mechanical Properties

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Journal of Materials Science & Technology 2006年第3期22卷 387-391页

作者： changzhong WU Huaining chen Jing chen Quanhong LIN Jianjun GUAN Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The explosion treatment technique has been used in the relief of residual stresses in 800 MPa grade high strength steel manual welded joints. The residual stresses on surface and through thickness of the weldment were measured for both as-welded and explosion-treated sample, the mechanical properties of welded joints under different conditions were also tested. The effect of explosion treatment on the fracture toughness of materials with a residual defect was investigated by crack opening displacement （COD） test. The results show that explosion treatment can reduce not only the surface residual stress but also the residual stress through thickness in the welded joints. The effect of explosion treatment on the mechanical properties and a residual defect in welded joint were inconspicuous.

关键词： High strength steel Explosion treatment Residual stress Mechanical properties COD test

Experiments and insights of desalination by a freezing/thawing method at low subcooling

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3011-3017页

作者： Jun chen Jianjian Wu Jiafeng Xu Qing Yuan Bin Deng changzhong chen Zhi Li Hunan Provincial Key Laboratory of Xiangnan Rare-PreciousMetals Compounds and Applications College of Chemistry&Biology and Environmental EngineeringXiangnanUniversityChenzhou 423000China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalian 116024China School of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China Shandong Provincial Key Laboratory of Molecular Engineering QiLu University of Technology(Shandong Academy of Sciences)Jinan 250353China

Desalination by freezing/thawing method was a very important method to obtain fresh water from *** this work,desalination by freezing/thawing method was conducted with initial sodium chloride of 3.5 wt% in consideration of stirring speed,freezing time and *** subcooling ranged from 1.2 K to 4 *** optimum conditions for desalination in this work were stirring speed of 200 r·min^−1,freezing time of 120 min,and subcooling of 3 *** results also showed that sodiumchloride cannot be effectively removed by once freezing/thawing *** maximumremoval efficiency of sodiumchloride was 64.3%.Two major reasons resulting in the impurity of obtained melted water by freezing/thawing method were *** first reason was the inevitable adhesion of salt solution to the surface of ice,which could be removed easily by distilled water *** second reason was that salt solution was heterogeneously wrapped in the accumulated ice,which was difficult to be removed by distilled water *** liquid flushing method was proposed to verify the conjecture,and the results were in accordance with the two reasons mentioned *** method,such as multiple flushing liquid method,was suggested to be used during the freezing/thawing process for effectively removing sodium chloride,and obtaining fresh water.

关键词： Desalination Ice Aqueous solution Separation Removal efficiency Mechanism

Synergistic photothermal effect and nanoenzyme for efficient antibacterial activity

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Science China Materials 2024年第9期67卷 2985-2994页

作者： Rong Li Shasha chen Xingang Zhang Fan Zeng Xianyin Song Jia Yin changzhong Jiang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha410081China Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation College of Life SciencesHunan Normal UniversityChangsha410081China College of Materials Science and Engineering Hunan UniversityChangsha410082China

The continuous emergence of drug-resistant bacteria has become a serious threat to human and animal *** new non-antibiotic therapeutic drugs with high efficiency and low resistance is a promising strategy for combating drug-resistant ***,a novel composite structure based on a hollow metal-organic framework(MOF)wrapped Au nanorod and loaded Pt nanoparticles(Au NR@H-ZIF-8@Pt)is designed for combating drug-resistant *** Au NR@H-ZIF-8@Pt composite structures serve a twofold purpose:(1)showing superior photothermal conversion efficiency under near-infrared light irradiation,thus achieving an antibacterial effect based on photothermal effect,and(2)exhibiting high-efficiency peroxidase-like activity,and effectively killing bacteria by reactive oxygen species(ROS)generated in *** combining photothermal and catalytic effects for in vitro antibacterial experiments,Au NR@H-ZIF-8@Pt exhibits efficient,rapid,broad-spectrum antibacterial activity(99.7%for Pseudomonas aeruginosa and 98.3%for Staphylococcus aureus).In addition,in vivo experiments further demonstrate the advantages of the material in promoting bacterial infection wound *** study not only facilitates the design of novel biological nanomaterials,but also provides new ideas for combating drug-resistant bacteria.

关键词： photothermal therapy nanoenzyme antibacterial treatment metal-organic framework

基于LESO的轮式移动机器人滑模轨迹跟踪控制

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四川轻化工大学学报（自然科学版） 2024年第1期37卷 51-60页

作者：罗淇陈昌忠刘鑫四川轻化工大学自动化与信息工程学院四川宜宾644000 人工智能四川省重点实验室四川宜宾644000

针对轮式移动机器人在车轮打滑情况下的轨迹跟踪控制问题,提出了一种利用线性扩张状态观测器(Linear Extended State Observer,LESO)和积分滑模面的控制方案。首先,根据车轮打滑情况下的非完整约束条件建立轮式移动机器人的运动学模型... 详细信息

针对轮式移动机器人在车轮打滑情况下的轨迹跟踪控制问题,提出了一种利用线性扩张状态观测器(Linear Extended State Observer,LESO)和积分滑模面的控制方案。首先,根据车轮打滑情况下的非完整约束条件建立轮式移动机器人的运动学模型。根据动能函数和拉格朗日方程建立其动力学模型。将这两种模型相结合得到力矩与速度相关的数学模型。其次,利用LESO对该数学模型进行扩张,并对总扰动进行估计。基于实际速度与虚拟速度之差设计带有积分项的滑模面,将扰动估计值前馈结合滑模面设计动力学控制器,并给出速度跟踪误差在有限时间内收敛的证明。最后,与基于超螺旋干扰观测器设计的控制方案仿真相比,所提出方案角速度跟踪误差在1 s左右时已趋于零,车轮力矩值稳定在3 N·m左右,且无锯齿抖动,扰动误差在1~5 s时波动更小,5~20 s时未出现明显锯齿抖动,仿真结果表明所提方案跟踪效果更好,抗干扰能力更强,观测精度更高。

关键词：轮式移动机器人轨迹跟踪车轮打滑线性扩张状态观测器滑模控制

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流行病学论文数据分析思路

中华流行病学杂志 2014年第6期35卷 745-748页

作者：王琳琳陈常中北京大学生育健康研究所和卫生部生育健康重点实验室北京大学公共卫生学院流行病与卫生统计学系 100191 美国哈佛大学医学院Dana-Farber癌症研究所

数据分析是根据现有认识对数据从不同角度进行统计分析，对结果进行解释、归纳，逐步形成新认识的过程，也就是将数据转换为证据的过程。分析结果最终以论文方式发表。准确、清晰、全面严谨的数据分析思路对形成有说服力的结论非常关键... 详细信息

数据分析是根据现有认识对数据从不同角度进行统计分析，对结果进行解释、归纳，逐步形成新认识的过程，也就是将数据转换为证据的过程。分析结果最终以论文方式发表。准确、清晰、全面严谨的数据分析思路对形成有说服力的结论非常关键。本文将就如何快速建立流行病学论文数据分析思路与分析方法进行探讨。

关键词：流行病学数据分析

Association of GYS1 and β_3-AR gene with postprandial hyperglycemia and serum uric acid in type 2 diabetes mellitus

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Chinese Medical Journal 2002年第9期115卷 28-31,145页

作者：王国英李琼芳牛天华陈常中徐希平北京大学第三医院内分泌科北京100083 TheProgramofPopulationGenetics

Objective To determine the relationships of Met416Val and XbaI polymorphism of muscle glycogen synthase (GYS1) gene and Trg64Arg variant of the β 3 adrenergic receptor (β 3 AR) gene with type 2 diabetes mellitus (DM) and its intermediate phenotypes in the Chinese population Methods Polymerase chain reaction oligonucleotide ligation assay and restriction fragment length polymorphism assay were used to evaluate the GYS1 and β 3 AR gene polymorphisms in 102 pairs of case control Chinese spouses Results Subjects with Met416Val variant had a significantly higher 2 hour post glucose level than subjects without this variant had in diabetic group ( P =0 032) The Met416Val polymorphism of GYS1 gene was not significantly associated with the risk of type 2 DM (adjusted OR=1 67; 95% CI: 0 73-3 81, P =0 223) Subjects with Trp64Arg variant had a significantly higher serum uric acid level than subjects without this variant had in diabetic group ( P =0 034) The combination of BMI and Arg64 allele carrier of the β 3 AR gene increased the diabetic risk over four fold (adjusted OR=4 00; 95%CI: 1 53-10 45, P =0 005) Conclusions In the Chinese population, Met416Val polymorphism is identified in a subgroup of diabetic subjects with high 2 hour post glucose It will explain why some diabetic patients appear to be genetically predisposed to developing high postpradial glucose level The presence of the Arg64 allele in the β 3 AR gene may predispose patients to higher serum uric acid level

关键词： muscle glycogen synthase gene· β3 adrenergic receptor gene· type 2 diabetes mellitus · postprandial glucose · serum uric acid

Victor-Carmen混沌系统的投影同步

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华中师范大学学报（自然科学版） 2016年第4期50卷 521-524页

作者：陈昌忠何平四川理工学院自动化与电子信息学院四川自贡643000

基于小增益理论,本文研究了一个新型Victor-Carmen混沌系统的投影同步问题.一个更为一般的达成投影同步的充分条件被推得.数值仿真验证了本文所设计的投影同步的有效性.

关键词： Victor-Carmen混沌系统投影同步小增益理论

The association between PPP1R3 gene polymorphisms and type 2 diabetes mellitus

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Chinese Medical Journal 2001年第12期114卷 26-30,102-103页

作者：王国英钱荣立李琼芳牛天华陈常中徐希平北京大学第三医院内分泌科北京大学第一医院内分泌科 The Channing Laboratory Department of Me dicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMA02115USA

Objective To detect the relationship between the polymorphism of the glycogen-targeting regulatory subunit of the skeletal muscle glycogen-associated protein phosphatase 1 (PPP1R3) gene and type 2 diabetes by case-control study. Methods We genotyped the PPP1R3 gene Asp905Tyr polymorphism and a common 3'-untranslated region AT (AU)-rich element (ARE) polymorphism in 101 type 2 diabetic patients and 101controls by oligonucleotide ligation assay (OLA) and polyacrylamide gel elecrophoresis, respectively. Results Subjects with Tyr/Tyr genotypes whose body mass index (BMI)<25 were used as the reference group. Those whose BMI25 with Asp905 had a 3.66-fold increase (95% CI: 1.48-9.06, P=0.005) in type 2 diabetes risk. No association was found between 3'UTR ARE polymorphism and type 2 diabetes mellitus (OR=1.15; 95% CI: 0.62-2.14, P=0.65). Conclusion A joint effect between the Asp905 and BMI increases the risk of type 2 diabetes, and Asp905Tyr and ARE polymorphism of PPP1R3 gene are not the major diabetogenic gene variants in Chinese population.

关键词： type 2 diabetes mellitus · PPP1R3 gene · polymorphism