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关键词： Steel corrosion  

摘要： A highly visible non-destructive evaluation method to monitor the progress of steel corrosion in concrete is strongly required. The purpose of this study is to propose an evaluation method using the electromagnetic field response, aiming to visualize the corrosion in a perspective view. At first, the detection mechanism of electromagnetic field response of fundamental notched patterns on the steel surface was considered. Second, an inverse problem analysis was performed. In detail, a visualizing method in the reverse direction that transforms the electromagnetic field response into a combination of magnetic changes of elementary waveforms of square-wave shaped surface and a reproducing method of the corrosion shape on 2-Dimensions by combining the elementary waveforms were proposed. The position and width of the defects, as well as the ratio of the depth of each defect, were well visualized. © 2025 The Society of Materials Science, Japan.

关键词： Saturation magnetization  

摘要： To fully account for the impact of magnetic saturation on the air‐gap magnetic field of a switched reluctance machine，a semi‐analytical model for the saturated air‐gap magnetic field was developed based on the theory of air‐gap magnetic field modulation. Based on the linear air‐gap magnetic field model，the model investigated the modulation effect of magnetic saturation on air‐gap permeance. The relationship between the saturation degree and the harmonics of air‐gap permeance was quantified. By acquiring a limited amount of sample data through finite element analysis，the saturated air‐gap permeance spectrum was reconstructed by interpolation method to correct the linear air‐gap magnetic field model affected by magnetic saturation. A finite element simulation model was constructed，and a threefold overload condition was selected to induce the machine to enter the deep saturation for simulation verification. A static flux‐linkage test platform was established for experimental verification. The simulation results indicate that the error between the proposed semi‐analytical method and finite element analysis is less than 1%. Experimental results demonstrate that the error between the proposed semi‐analytical method and the measured results is less than 10%. This method enables a rapid assessment of the fundamental electromagnetic performance of machine，overcoming the drawbacks of the long computation time associated with pure finite element methods and the complex derivation required for pure analytical methods. © 2025 Southeast University. All rights reserved.

关键词： economic crisis   environmental, health and safety risk regulation   European Union   ratcheting up   regulatory convergence  

摘要： The European Union was hit by the financial crisis of 2008. The impact of this crisis, however, and the extent to which this has led to strengthening environmental, health and safety risk regulation in the EU remain open to debate. This article advances the discussion of the "ratcheting-up" hypothesis by adding a new explanatory factor, namely the financial crisis, and shows what role it played in two cases of risk regulation: Nanotechnology and Alien Invasive Species. It is argued that the crisis, acting as an external economic pressure for the competitiveness and growth of the single market, advanced the economic rationale for strengthening environmental, health and safety standards with implications for effective risk governance, namely regulatory convergence across its (then) 28 member states.

关键词： Steel analysis  

摘要： This study presents a formulation method for implementing a material constitutive model using a memory surface in finite element analysis, capable of accurately reproducing the cyclic hardening and softening behavior of SN490B structural steel under constant strain amplitude. The formulation employs an implicit discretization method, specifically the backward Euler method. For solving plastic multipliers, elastic predictors and plastic correctors are used. Additionally, to ensure the convergence and stability of the nonlinear analysis, the derivation of the consistent tangent modulus tensor is demonstrated. The validity of the modeling method was verified through finite element analysis. © 2025 Architectural Institute of Japan. All rights reserved.

关键词： 高三   生物复习课   科学探究能力   问题情境   实验  

摘要： 培养学生学科核心素养是高中生物教学中的主要任务,科学探究能力作为核心素养中的重要内容,要求教师能够在教学实践中加以重点培养.从历年高考情况来看,科学探究素养也是生物高考中重点考察的内容.因此,在高三生物复习课中,教师要带领学生巩固基础知识的同时,重视训练和提升学生科学探究能力.基于此,文章分析高三生物复习课中培养学生科学探究能力的价值及现状,进而具体探讨培养学生科学探究能力的实践策略,以期为提升高三复习课教学效果提供参考.

摘要： ★《守株待兔》是部编版《语文》三年级下册的一篇古典寓言,其深邃的含义对人们的生活态度和行为选择具有重要启示.解析这一经典寓言蕴含的多重含义,探讨人性弱点的产生机理及人生警示、机遇与努力的辩证关系,提醒人们切勿沉溺于偶然的成功或幻想不劳而获,而应积极面对挑战,主动出击,以勤奋和智慧去创造属于自己的机遇与未来.

关键词： 胆管癌   伴破骨细胞样巨细胞的未分化癌   软组织巨细胞瘤  

摘要： 目的:探讨伴破骨细胞样巨细胞的未分化癌的临床表现及病理特征，旨在提高临床医师对该罕见肿瘤的认识，避免误诊、漏诊。方法:结合2022年烟台市烟台山医院收治的1例肝内胆管原发的伴破骨细胞样巨细胞的未分化癌，回顾性分析1980—2024年间发表的胆管及肝脏内发生的类似病变共30例，总结了该病的流行病学、临床影像、病理特征、治疗以及预后。结果:伴破骨细胞样巨细胞的未分化癌主要发生在男性，中老年人多见。临床主要表现为腹部疼痛不适、腹部肿块、恶心、黄疸等。该肿瘤常缺乏上皮分化的证据，病理医师对其认识有限，所以诊断名称非常混乱，误诊较多。此外，该肿瘤恶性程度高，早期就出现肝内血管或区域淋巴结转移，生存期从几周到几个月不等。结论:伴破骨细胞样巨细胞的未分化癌是一种非常罕见的、具有间充质特征的肉瘤样癌，推测其发生机制可能与上皮-间质转化有关。该肿瘤预后极差，及早发现和手术完整切除可能是目前改善患者预后的唯一手段。