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Analysis on annealing-induced stress of blind-via TSV using FEM

Jie SHAO, Tielin SHI, Li DU, Lei SU, Xiangning LU, Guanglan LIAO

《机械工程前沿（英文）》 2018年第13卷第3期页码 401-410 doi: 10.1007/s11465-017-0457-7

摘要：

Copper-filled through silicon via (TSV) is a promising material owing to its application in high-density three-dimensional (3D) packaging. However, in TSV manufacturing, thermo-mechanical stress is induced during the annealing process, often causing reliability issues. In this paper, the finite element method is employed to investigate the impacts of via shape and SiO₂ liner uniformity on the thermo-mechanical properties of copper-filled blind-via TSV after annealing. Top interface stress analysis on the TSV structure shows that the curvature of via openings releases stress concentration that leads to ~60 MPa decrease of normal stresses, s_xx and s_yy, in copper and ~70 MPa decrease s_xx of in silicon. Meanwhile, the vertical interface analysis shows that annealing-induced stress at the SiO₂/Si interface depends heavily on SiO₂ uniformity. By increasing the thickness of SiO₂ linear, the stress at the vertical interface can be significantly reduced. Thus, process optimization to reduce the annealing-induced stress becomes feasible. The results of this study help us gain a better understanding of the thermo-mechanical behavior of the annealed TSV in 3D packaging.

关键词： through silicon via (TSV) annealing-induced stress interface stress plastic deformation finite element method

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The early signal substances induced by heat stress in brains of mice

WANG Chunxu, WANG Hanxing

《医学前沿（英文）》 2008年第2卷第4期页码 391-395 doi: 10.1007/s11684-008-0075-1

摘要： To study the effects of early signal substances induced by heat stress in brains of Kunming mice, six-month-old mice ( = 72) were pretreated with heat stress and subsequent ischemia/reperfusion by clipping of their bilateral cervical common arteries for 7 min. According to different treatments, animals were randomly divided into four groups: (1) normal control group; (2) heat stress pretreatment followed by ischemia and reperfusion group (HS/IR); (3) ischemia and reperfusion group (IR); (4) heat stress group (HS). Animals in the later three groups were subdivided into 3 subgroups (1 day, 4 days, 14 days), respectively. The changes in the expression of cAMP response element binding protein (CREB) and calcitonin gene-related peptide (CGRP) were detected by immunohistochemistry and computer image analysis methods. The results showed that compared with the normal group, the expressions of CREB in the hippocampal CA1 region increased significantly in the HS, HS/IR and IR groups ( < 0.05). Compared to the normal group, heat stress could result in CGRP excretion and redistribution in the cerebrum, with the highest level in the 4 d HS/IR group. Following heat stress, CGRP immunoreactivity was observed in varicose fibers and neuronal perikarya within the CA1 region. The results indicate that heat stress can induce CREB expression, which in turn stimulates CGRP secretion.

关键词： calcitonin gene-related subsequent ischemia/reperfusion computer cerebrum CGRP excretion

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煤矿开采动静载叠加诱发断层冲击地压机理 Article

蔡武, 窦林名, 司光耀, 胡亚伟

《工程（英文）》 2021年第7卷第5期页码 687-700 doi: 10.1016/j.eng.2020.03.017

摘要：

断层作为煤层采掘过程中普遍存在的一种地质构造，其独特不连续结构控制着煤岩的变形、破坏与力学性质，该结构与煤层采掘活动之间的相互作用是断层活化及其诱发冲击地压的关键。本文通过调研总结煤层采掘活动与断层赋存状态之间的概念模型，提出了采动应力主导和矿震动载主导两种断层活化类型的力学机制及其动静载叠加诱冲机理；其次，结合物理实验、数值模拟和现场微震监测结果验证了模型与机理的合理性；在此基础上，针对性地探讨了断层冲击地压监测与防治的方法和策略。研究结果表明，断层冲击地压是由断层煤柱高静载与断层活化动载叠加诱发，其中，断层煤柱高静载是断层与顶板结构双重作用导致，断层活化动载是由采动应力主导型局部解锁活化、等效劈裂破坏和矿震动载主导型超低摩擦效应组成。研究结果对于系统理解断层冲击地压机理、监测与防治具有重要指导意义。

关键词：冲击地压断层活化采动应力矿震动载应力断层煤柱

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Apigenin alleviates neomycin-induced oxidative damage via the Nrf2 signaling pathway in cochlear hair

《医学前沿（英文）》 2022年第16卷第4期页码 637-650 doi: 10.1007/s11684-021-0864-3

摘要： Oxidative stress plays an important role in the pathogenesis of aminoglycoside-induced hearing loss and represents a promising target for treatment. We tested the potential effect of apigenin, a natural flavonoid with anticancer, anti-inflammatory, and antioxidant activities, on neomycin-induced ototoxicity in cochlear hair cells in vitro. Results showed that apigenin significantly ameliorated the loss of hair cells and the accumulation of reactive oxygen species upon neomycin injury. Further evidence suggested that the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway was activated by apigenin treatment. Disruption of the Nrf2 axis abolished the effects of apigenin on the alleviation of oxidative stress and subsequent apoptosis of hair cells. This study provided evidence of the protective effect of apigenin on cochlear hair cells and its underlying mechanism.

关键词： apigenin aminoglycosides ototoxicity oxidative stress Nrf2 signaling pathway

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Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

《机械工程前沿（英文）》 2011年第6卷第3期页码 287-291 doi: 10.1007/s11465-011-0230-2

摘要：

The dynamic responses of ferroelectric materials upon external mechanical and electrical stimulations are inherently nonlinear and coupled. In the current paper, a macroscopic differential model is constructed for the coupled hysteretic dynamics via modeling the orientation switching induced in the materials. A non-convex potential energy is constructed with both mechanic and electric field contributions. The governing equations are formulated as nonlinear ordinary differential equations by employing the Euler-Lagrange equation, and can be easily recast into a state space form. Hysteresis loops associated with stress induced polarization switching and butterfly-shaped behavior in ferroelectric materials are also successfully captured. The effects of mechanical loadings on the electrically induced switching are numerically investigated, as well as the mechanically-induced switching with various bias electric fields.

关键词： differential model state space electromechanical switching butterfly effects hysteresis

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Unified description of sand behavior

Feng ZHANG, Bin YE, Guanlin YE

《结构与土木工程前沿（英文）》 2011年第5卷第2期页码 121-150 doi: 10.1007/s11709-011-0104-z

摘要： In this paper, the mechanical behavior of sand, was systematically described and modeled with a elastoplastic model proposed by Zhang et al. [ ]. Without losing the generality of the sand, a specific sand called as Toyoura sand, a typical clean sand found in Japan, has been discussed in detail. In the model, the results of conventional triaxial tests of the sand under different loading and drainage conditions were simulated with a fixed set of material parameters. The model only employs eight parameters among which five parameters are the same as those used in Cam-clay model. Once the parameters are determined with the conventional drained triaxial compression tests and undrained triaxial cyclic loading tests, then they are fixed to uniquely describe the overall mechanical behaviors of the Toyoura sand, without changing the values of the eight parameters irrespective of what kind of the loadings or the drainage conditions may be. The capability of the model is discussed in a theoretical way.

关键词： constitutive model sand stress-induced anisotropy density structure

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Pragmatic multi-stage simulated annealing for optimal placement of synchrophasor measurement units in

Pathirikkat GOPAKUMAR,M. JAYA BHARATA REDDY,Dusmata Kumar MOHANTA

《能源前沿（英文）》 2015年第9卷第2期页码 148-161 doi: 10.1007/s11708-015-0344-z

摘要： Conventional power grids across the globe are reforming to smart power grids with cutting edge technologies in real time monitoring and control methods. Advanced real time monitoring is facilitated by incorporating synchrophasor measurement units such as phasor measurement units (PMUs) to the power grid monitoring system. Several physical and economic constraints limit the deployment of PMUs in smart power grids. This paper proposes a pragmatic multi-stage simulated annealing (PMSSA) methodology for finding the optimal locations in the smart power grid for installing PMUs in conjunction with existing conventional measurement units (CMUs) to achieve a complete observability of the grid. The proposed PMSSA is much faster than the conventional simulated annealing (SA) approach as it utilizes controlled uphill and downhill movements during various stages of optimization. Moreover, the method of integrating practical phasor measurement unit (PMU) placement conditions like PMU channel limits and redundant placement can be easily handled. The efficacy of the proposed methodology has been validated through simulation studies in IEEE standard bus systems and practical regional Indian power grids.

关键词： phasor measurement units (PMUs) pragmatic PMU placement simulated annealing (SA) western region Indian power grid (WRIPG)

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TA2板料激光热应力弯曲成形及其力学性能研究

周益军,张永康,游文明

《中国工程科学》 2007年第9卷第10期页码 40-44

摘要：

用HVS-1000显微硬度测试仪、X-350A型X射线应力测定仪，以2.5 kW SM2000SM快轴流CO₂激光器对0.6 mm厚的TA2板料进行扫描，按照正交试验理论安排成形工艺参数，研究了TA2板料弯曲成形时主要工艺参数对弯曲角度的影响，以及试样表面残余应力的分布和试样断面上的显微硬度变化。结果表明：正交试验中的4个工艺参数的作用是不同的，按其变化对弯曲变形量影响的大小排序，依次是扫描次数、光斑直径、激光束功率、扫描速度；成形参数对试样表面的残余应力分布也存在一定的影响；试样变形区断面上的显微硬度变化呈现出一定的规律。

关键词：激光技术热应力板料弯曲成形残余应力显微硬度

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Reliability analysis on civil engineering project based on integrated adaptive simulation annealing and

Xiao-ping BAI,Ya-nan LIU

《结构与土木工程前沿（英文）》 2016年第10卷第4期页码 462-471 doi: 10.1007/s11709-016-0361-y

摘要： Dynamic reliability is a very important issue in reliability research. The dynamic reliability analysis for the project is still in search of domestic and international research in the exploration stage. By now, dynamic reliability research mainly concentrates on the reliability assessment; the methods mainly include dynamic fault tree, extension of event sequence diagram and Monte Carlo simulation, and et al. The paper aims to research the dynamic reliability optimization. On the basis of analysis of the four quality influence factors in the construction engineering, a method based on gray correlation degree is employed to calculate the weights of factors affecting construction process quality. Then the weights are added into the reliability improvement feasible index (RIFI). Furthermore, a novel nonlinear programming mathematic optimization model is established. In the Insight software environment, the Adaptive Simulated Annealing (ASA) algorithm is used to get a more accurate construction subsystem optimal reliability under different RIFI conditions. In addition, the relationship between construction quality and construction system reliability is analyzed, the proposed methods and detailed processing can offer a useful reference for improving the construction system quality level.

关键词： civil engineering dynamic reliability grey relational degree adaptive simulated annealing algorithm

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Thermal annealing synthesis of double-shell truncated octahedral Pt-Ni alloys for oxygen reduction reaction

Xiashuang LUO, Yangge GUO, Hongru ZHOU, Huan REN, Shuiyun SHEN, Guanghua WEI, Junliang ZHANG

《能源前沿（英文）》 2020年第14卷第4期页码 767-777 doi: 10.1007/s11708-020-0667-2

摘要： Shape-controlled Pt-Ni alloys usually offer an exceptional electrocatalytic activity toward the oxygen reduction reaction (ORR) of polymer electrolyte membrane fuel cells (PEMFCs), whose tricks lie in well-designed structures and surface morphologies. In this paper, a novel synthesis of truncated octahedral PtNi alloy catalysts that consist of homogeneous Pt-Ni alloy cores enclosed by NiO-Pt double shells through thermally annealing defective heterogeneous PtNi alloys is reported. By tracking the evolution of both compositions and morphologies, the outward segregation of both PtO and NiO are first observed in Pt-Ni alloys. It is speculated that the diffusion of low-coordination atoms results in the formation of an energetically favorable truncated octahedron while the outward segregation of oxides leads to the formation of NiO-Pt double shells. It is very attractive that after gently removing the NiO outer shell, the dealloyed truncated octahedral core-shell structure demonstrates a greatly enhanced ORR activity. The as-obtained truncated octahedral Pt Ni core-shell alloy presents a 3.4-folds mass-specific activity of that for unannealed sample, and its activity preserves 45.4% after 30000 potential cycles of accelerated degradation test (ADT). The peak power density of the dealloyed truncated octahedral Pt Ni core-shell alloy catalyst based membrane electrolyte assembly (MEA) reaches 679.8 mW/cm , increased by 138.4 mW/cm relative to that based on commercial Pt/C.

关键词： dealloyed Pt-Ni alloys truncated octahedron double-shell thermal annealing oxygen reduction reaction (ORR)

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含磷低硅TRIP 钢快速退火组织演变行为研究

陈蓬,沈春豫,许云波,王国栋

《中国工程科学》 2014年第16卷第1期页码 48-53

摘要：

通过实验室热处理模拟实验，对含磷低硅transformation induced plasticity（TRIP）钢快速退火过程中各个阶段的组织演变行为进行研究，主要研究了不同退火温度对各个阶段组织组成的影响

关键词：汽车钢 TRIP钢低硅快速退火组织演变

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基于退火算法的物流配送网的求优研究

段敬民,常跃军,李赞祥,崔建明

《中国工程科学》 2012年第14卷第7期页码 109-112

摘要：

模拟退火算法是一种启发式算法，是受到加热紧缩的退火过程所启发而提出来的求解组合优化问题的一种逼近算法。算法要优于传统的贪婪算法，避免了陷入局部最优的可能，从而达到全局最优解。在物流配送网络中经常有一些寻求最短路径等问题出现，为了能够达到最短、最优、最经济等，需要进行物流配送路径寻优。文中采用模拟退火算法进行一个示例的验证，效果证明可行。

关键词：模拟退火算法全局最优解物流配送网

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基于修正模拟退火算法及溢出面积模型的固定边界布图规划 Article

De-xuan ZOU,Gai-ge WANG,Gai PAN,Hong-wei QI

《信息与电子工程前沿（英文）》 2016年第17卷第11期页码 1228-1244 doi: 10.1631/FITEE.1500386

摘要：第一，提出了一种修正模拟退火算法（Modified simulated annealing algorithm, MSA）。

关键词：固定边界布图规划；修正的模拟退火算法；全局搜索；溢出面积模型；B*-tree表示法

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基于本体和模拟退火算法的暴雨灾害主题爬虫策略 Research Article

刘景发1,2,李帆3,丁若尧1,2,刘子昂4

《信息与电子工程前沿（英文）》 2022年第23卷第8期页码 1189-1204 doi: 10.1631/FITEE.2100360

摘要：目前，主题爬虫是从海量异构网络中获取有效领域知识的重要方法。目前大多数主题爬虫技术难以获得高质量爬行结果。主要难点包括主题基准模型的建立、超链接主题相关性的评估和爬行策略的设计。本文采用领域本体为特定主题构建主题基准模型，并提出一种新的基于局部本体和全局本体的多重筛选策略（MFSLG）。为提高待访问超链接主题相关性计算精度，提出一种基于网页文本和链接结构的综合优先度评估方法（CPEM），同时，采用模拟退火（SA）算法避免主题爬虫陷入局部最优搜索。本文首次设计融合SA算法、MFSLG策略和CPEM策略实现主题爬虫，提出两种新的基于本体和SA主题爬虫策略（FCOSA），包括基于全局本体的FCOSA策略（FCOSA_G）和基于局部本体和全局本体的FCOSA策略（FCOSA_LG），以从网络中获取与暴雨灾害主题相关的网页。实验结果表明，针对不同性能指标，所提爬虫策略优于其他主题爬虫策略。

关键词：主题爬虫；本体；优先度评估；模拟退火；暴雨灾害

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Treatment of gingival hyperplasia induced by cyclosporine A

MA Jingzhi, LI Ming, CAO Yingguang

《医学前沿（英文）》 2008年第2卷第3期页码 290-294 doi: 10.1007/s11684-008-0055-5

摘要： The clinical therapy for cyclosporine A (CsA)-induced gingival hyperplasia (GH) and the pathological changes in hyperplastic gingival tissues were investigated. Nine cases of CsA-induced GH after renal transplantation were subjected to periodontal non-surgical treatment and surgical treatment and were followed up. Gingival index (GI), dental plaque index (PLI) and GH degree (GHD) at different time points were measured. Under light and electron microscopy, the pathological changes in hyperplastic gingival tissues were observed. The CsA concentrations in gingival tissues and blood were determined by using fluorescence polarization immunoassay with TDFL monoclonal antibody. The results showed that GI, PLI and GHD in patients with GH declined after periodontal treatment. Two patients suffered from different degrees of GH during the 6 months to 54 months post-transplantation. Under transmission electron microscopy, fibroblasts in the hyperplastic gingival tissues were enlarged, cytoplasmic rough endoplasmic reticula were abundant and expanded slightly, and a few fibroblasts with early apoptotic changes were seen. The concentrations of CsA in hyperplastic gingival tissues were from 351.00 to 1345.47 ng/mL, which were significantly higher than in the blood of the same patients taken at the same time points. It was concluded that GI and PLI declined after periodontal treatment in combination with surgical treatment in patients taking CsA for a long time, but in some patients, GH recurred. The fact that the concentration of CsA in hyperplastic gingival tissues is higher than in blood awaits further studies.

关键词： post-transplantation Gingival cytoplasmic CsA-induced further