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代表性体积元 1

多尺度均质化 1

晶格离散粒子模型 1

架构上重要的需求（ASR）；架构权衡分析法（ATAM）；互联网架构板；物联网；隐私增强技术；隐私验证链 1

碱硅反应 1

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物联网隐私与安全联合参考架构 Position Paper

Musab KAMAL1, Imran RASHID1, Waseem IQBAL1, Muhammad Haroon SIDDIQUI1, Sohaib KHAN1, Ijaz AHMAD2

《信息与电子工程前沿（英文）》 2023年第24卷第4期页码 481-508 doi: 10.1631/FITEE.2200368

摘要：各种物体正以惊人速度连接到互联网，使物联网概念成为现实。物联网生态系统正以智能家居、医疗保健系统、可穿戴设备、联网车辆和多种产业形式普及，由此增加了与系统隐私和安全相关的风险。架构缺陷带来的物联网设备安全问题和网络攻击可能阻碍物联网产品的发展。解决这些问题，需在物联网构建块中设置隐私和安全权限。多年来，物联网架构不断演变，通过可测量性、管理、互操作性和可扩展性等新方案改进了架构。为此，亟需结合隐私和安全考量，对物联网参考架构进行标准化和有效管理。本文检查了12个现有物联网参考架构，对照标准中的要求，分析各自不足之处。基于此，提出一种新的架构，即结合隐私的物联网安全参考架构（PF-IoT-SRA），其诠释了物联网通信环境中所有隐私指标，可以对抗主要威胁和攻击。这是朝着领域架构标准化迈出的一步。我们使用架构权衡分析法（ATAM）——一种行业认可的基于场景的方法——验证了所提参考架构的有效性。

关键词：架构上重要的需求（ASR）；架构权衡分析法（ATAM）；互联网架构板；物联网；隐私增强技术；隐私验证链

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An Algorithm to compute damage from load in composites

Cyrille F. DUNANT, Stéphane P. A. BORDAS, Pierre KERFRIDEN, Karen L. SCRIVENER, Timon RABCZUK

《结构与土木工程前沿（英文）》 2011年第5卷第2期页码 180-193 doi: 10.1007/s11709-011-0107-9

摘要： We present a new method to model fracture of concrete based on energy minimisation. The concrete is considered on the mesoscale as composite consisting of cement paste, aggregates and micro pores. In this first step, the alkali-silica reaction is taken into account through damage mechanics though the process is more complex involving thermo-hygro-chemo-mechanical reaction. We use a non-local damage model that ensures the well-posedness of the boundary value problem (BVP). In contrast to existing methods, the interactions between degrees of freedom evolve with the damage evolutions. Numerical results are compared to analytical and experimental results and show good agreement.

关键词： Concrete damage prediction modelling energy minimisation ASR

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A general framework for modeling long-term behavior of earth and concrete dams

Bernhard A. SCHREFLER, Francesco PESAVENTO, Lorenzo SANAVIA, Giuseppe SCIUME, Stefano SECCHI, Luciano SIMONI

《结构与土木工程前沿（英文）》 2011年第5卷第1期页码 41-52 doi: 10.1007/s11709-010-0070-x

摘要： Many problems are linked with the long-term behavior of both earthdams and concrete dams. They range from hydraulic fracturing to alkali-silica reaction (ASR) and to repair work in concrete dams, from seismic behavior to secondary consolidation in earthdams. A common framework for the simulation of such systems is shown, based on the mechanics of multiphase porous media. The general model is particularized to specific situations and several examples are shown.

关键词： earth dams concrete dams multiphase porous materials coupled problems hydraulic fracture concrete hydration alkali-silica reaction (ASR) finite element method

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混凝土中碱硅反应效应的多尺度均质化分析 Article

Roozbeh Rezakhani, Mohammed Alnaggar, Gianluca Cusatis

《工程（英文）》 2019年第5卷第6期页码 1139-1154 doi: 10.1016/j.eng.2019.02.007

摘要：

碱硅反应（ASR）是混凝土结构（如桥梁和水坝）在长期的高湿度环境下发生的主要劣化机制之一。ASR是骨料中活性硅成分与水泥浆中碱金属离子之间发生的一种化学反应。这种化学反应会产生ASR凝胶，该凝胶吸水后膨胀，造成混凝土损坏和开裂，最终导致混凝土力学性能下降。本研究基于晶格离散粒子模型（LDPM），研究了混凝土的ASR损伤。作者已经成功地利用LDPM框架对ASR建模，并且通过实验数据对所得模型ASR-LDPM进行了校准和验证。本研究将ASR-LDPM用作中尺度模型，并采用最新开发的多尺度均质化框架来模拟ASR的宏观尺度效应。作者首先分析了由ASR-LDPM模拟的混凝土代表性体积元（RVE）在拉伸和压缩两种情况下的均质化行为，并研究了ASR对混凝土有效力学性能的影响。

关键词：多尺度均质化代表性体积元碱硅反应晶格离散粒子模型

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Modeling of alkali-silica reaction in concrete: a review

J.W. PAN, Y.T. FENG, J.T. WANG, Q.C. SUN, C.H. ZHANG, D.R.J. OWEN

《结构与土木工程前沿（英文）》 2012年第6卷第1期页码 1-18 doi: 10.1007/s11709-012-0141-2

摘要： This paper presents a comprehensive review of modeling of alkali-silica reaction (ASR) in concrete. Such modeling is essential for investigating the chemical expansion mechanism and the subsequent influence on the mechanical aspects of the material. The concept of ASR and the mechanism of expansion are first outlined, and the state-of-the-art of modeling for ASR, the focus of the paper, is then presented in detail. The modeling includes theoretical approaches, meso- and macroscopic models for ASR analysis. The theoretical approaches dealt with the chemical reaction mechanism and were used for predicting pessimum size of aggregate. Mesoscopic models have attempted to explain the mechanism of mechanical deterioration of ASR-affected concrete at material scale. The macroscopic models, chemo-mechanical coupling models, have been generally developed by combining the chemical reaction kinetics with linear or nonlinear mechanical constitutive, and were applied to reproduce and predict the long-term behavior of structures suffering from ASR. Finally, a conclusion and discussion of the modeling are given.

关键词： alkali-silica reaction (ASR) modeling concrete mesoscopic macroscopic

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Utilization of nano/micro-size iron recovered from the fine fraction of automobile shredder residue for phenol degradation in water

Jiwan SINGH, Yoon-Young CHANG, Jae-Kyu YANG, Seon-Hong KANG, Janardhan Reddy KODURU

《环境科学与工程前沿（英文）》 2016年第10卷第4期 doi: 10.1007/s11783-016-0848-8

摘要： Phenol removal by n/m Fe in the presence of H O was highly effective. Increasing the amounts of n/m Fe and H O ?increased the phenol removal rate. Phenol removal was decreased with an increase in the concentration of phenol. The natural pH (6.9) of the solution was highly effective for phenol removal. The pseudo-first-order kinetics was best fitted for the degradation of phenol. The study investigates the magnetic separation of Fe from automobile shredder residue (ASR) (<0.25 mm) and its application for phenol degradation in water. The magnetically separated Fe was subjected to an ultrasonically assisted acid treatment, and the degradation of phenol in an aqueous solution using nano/micro-size Fe (n/m Fe) was investigated in an effort to evaluate the possibility of utilizing n/m Fe to remove phenol from wastewater. The prepared n/m Fe was analyzed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The effects of the dosages of n/mFe, pH, concentration of phenol and amount of H O on phenol removal were evaluated. The results confirm that the phenol degradation rate was improved with an increase in the dosages of n/mFe and H O ; however, the rate is reduced when the phenol concentration is higher. The degradation of phenol by n/mFe followed the pseudo-first-order kinetics. The value of the reaction rate constant ( was increased as the amounts of n/m Fe and H O increased. Conversely, the value of was reduced when the concentration of phenol was increased. The probable mechanism behind the degradation of phenol by n/m Fe is the oxidation of phenol through hydroxyl radicals which are produced during the reaction between H O and n/m Fe.

关键词： Automobile shredder residue (ASR) Fe Phenol Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) Mechanism