摘要：Vibration behaviors of bogie hunting motion contain key information that dominates the dynamic performance of rail vehicles,in which the eigenvalue of each mode reflects the damping ratio and the natural *** paper focuses on the root loci curves of bogie hunting motion,starting from a rigid bogie,then to a bogie with flexible primary *** regard to the rigid bogie,analytical formulas for the eigenvalues,the critical speed as well as the corresponding hunting frequency are derived and *** for the flexible bogie,the root loci curves are calculated *** study shows that both free rigid bogie and free wheelset are dynamically unstable at any *** critical speed increases with diminished wheel-rail conicity,track gauge,and wheelset and bogie inertia,and with increased wheelbase and wheel *** dominating factors such as the stiffness of the primary suspension and the wheel-rail conicity should be optimized for a practical *** influences of the damping coefficients and the variations of creep coefficients are *** motor suspension affects the root loci curves and the critical speed *** inappropriate motor suspension design and rigidly suspended motor reduce the critical *** increase of critical speed by a motor suspension can only be achieved when the lower natural frequency of the motor-bogie frame-wheelsets system coincides with or is close to the hunting *** care should be taken for the design of motor suspension,the first is to avoid the decreased damping ratio in a certain speed range below the critical speed and the second is that the variations of parameters should not induce the rapid reduction of the critical *** main feature of the present study is that the root loci curves,which are derived as analytical formulas or calculated numerically,are used to study the vibrational behaviors of bogie hunting *** the influencing laws of the dominating pa

摘要：In this paper, we present a comprehensive model for the prediction of the evolution of high-speed train wheel profiles due to wear. The model consists of four modules： a multi-body model implemented with the commercial multi-body software SIMPACK to evaluate the dynamic response of the vehicle and track; a local contact model based on Hertzian theory and a novel method, named FaStrip （Sichani et al., 2016）, to calculate the normal and tangential forces, respectively; a wear model proposed by the University of Sheffield （known as the USFD wear function） to estimate the amount of material removed and its distribution along the wheel profile; and a smoothing and updating strategy. A simulation of the wheel wear of the high-speed train CRH3 in service on the Wuhan-Guangzhou railway line was performed. A virtual railway line based on the statistics of the line was used to represent the entire real track. The model was validated using the wheel wear data of the CRH3 operating on the Wuhan- Guangzhou line, monitored by the authors＇ research group. The results of the predictions and measurements were in good agreement.

摘要：定向电荷转移是调控光生载流子分离动力学的一种极具吸引力的策略。本文通过在SnNb_(2)O_(6)纳米片上原位生长C_(3)N_(5)纳米棒,设计一种具有强内建电场(IEF)和偶极场(DF)的新型2D/1D SnNb_(2)O_(6)/富氮C_(3)N_(5)S型异质结。通过构筑S型异质结,在界面处产生IEF,促进电荷从SnNb_(2)O_(6)向C_(3)N_(5)的定向迁移。与此同时,C_(3)N_(5)中的DF提供一种驱动力,将光生电子定向转移至活性位点。通过IEF和DF的协同效应,SnNb_(2)O_(6)/C_(3)N_(5)异质结实现了快速的定向电子转移,从而显著提高了电荷分离效率。研究结果表明,SnNb_(2)O_(6)/C_(3)N_(5)异质结的最佳产氢速率高达1090.0μmol·g^(-1)·h^(-1)(反应过程中持续释放H2气泡),分别是SnNb_(2)O_(6)和C_(3)N_(5)的38.8和10.7倍。此外,SnNb_(2)O_(6)/C_(3)N_(5)异质结在去除罗丹明B、四环素和Cr(Ⅵ)方面也表现出优异的光催化性能。通过电子顺磁共振(EPR)、时间分辨光致发光光谱(TPRL)和密度泛函理论(DFT)计算,本文系统探讨了SnNb_(2)O_(6)/C_(3)N_(5)异质结的定向电荷转移机制。这项研究为开发高效异质结光催化剂提供了一种可行的方法。

摘要：针对工业过程中一阶纯滞后系统Smith补偿控制方法易受模型不确定性或扰动影响的问题,提出了一种改进的Smith-IFT控制方法。首先利用过程模型,通过优化灵敏度函数的H_(∞)范数设计Smith控制器C_(1),以提升系统输出性能;同时,采用迭代反馈整定(IFT)方法设计数据驱动控制器C_(2),并更新预估模型和控制器C_(1),以降低模型不确定性或扰动的影响。以实际工业过程纸浆浓度控制为例,仿真验证了所提方法的有效性。与其他两种方法相比,改进的Smith-IFT控制方法具有超调量小、调节时间短和鲁棒性强等优势。

摘要：This paper adopts a New Historicism approach to examine the shaping of the history of the dunkirk evacuation through an analysis of Winston Churchill’s historic speech We Shall Fight on the Beaches,Ian McEwan’s novel Atonement,and Christopher Nolan’s film *** research reveals that by uncovering and representing the neglected stories of marginalized groups in Atonement and dunkirk,new evidentiary threads both enrich and contest the History embodied in Churchill’s ***,these alternative accounts both challenge and complement the prevailing historical discourse.

摘要：Arnold Bennett is well-known for his regional novels that mainly represent domestic quotidian lives of his pottery town,especially the lower and middle ***,his infatuation with the hotel space implicates his ambition to re-situate his characters within the parameters of hotel and create new types of characters,representing in new ways the subjectivity of characters and their relations with material *** on his hotel writing,this article intends to re-conceive the historical reasons of his obsession with hotel space and further probe the modernity deflected by his representation of domestic selves and modern public identities in hotel space.

摘要：设计思维是创新性思维在设计活动中的具体呈现,也是设计领域对人类创新认知活动的独特贡献。面向设计思维应用领域不断扩展的趋势和发展的设计思维研究方法体系,本文总结了设计思维研究领域近40年来的变化,从设计思维的本体认知、内涵厘清及理论范式等方面归纳了现有研究的方法体系,通过多年的跟踪采集,分析了4397余次互动行为数据,278.2小时有声思维数据,9784.3兆脑电特征数据,建构了设计思维对象可捕捉、设计活动可追溯、认知可验证的完整解读链路。

摘要：岩彩画艺术是中国古代传统美术的一部分。历史上由遣唐使传输至日本,日本画家在长期实践探索中,从材料研发到表现语言都有新的发展。新时期以来,中国留日画家在秉承前辈改良中国画的愿景中将这一绘画重新带回中国。经过不断的推广与创新,最终完成了岩彩画在本土的现代复兴,从而使岩彩画成为中国美术中一次成功的推陈出新。在各高校内开展的岩彩画教学,更是依托本土石窟艺术资源,建构起较为完整的教学体系,实现了优秀传统文化的创造性转化和创新性发展。在持续深入的岩彩画理论探讨中,对这一绘画的来源生成及历史追溯有了清醒认识,岩彩画更成为凸显民族文化基因及传统艺术向现代转型的表征。对岩彩画发展历程的追溯和文化基因的解析,都是以更加开放的视角去理解岩彩画在不同时期、不同文化背景中的衍生、演变和传播,岩彩画也由此成为当代文化交流、互鉴、共生、创新的艺术典范。

摘要：研究目的:采用ANSYS软件计算某地铁车站的土-结构体系在地震荷载作用下的动力响应问题,对土-结构相互作用体系模型的建立、模型参数的确定、人工边界条件的设置等问题进行分析,探索地铁车站在水平地震作用下的内力和变形规律。研究结论:(1)地下结构的动力响应特征主要受周围土体介质的特性影响,在水平地震作用下,其水平位移受到周围土体的约束,随土体共同运动,沿结构高度变化不大;(2)结构的外围构件由于直接与土相互作用,一般承受较大的弯矩;(3)中间柱会产生较大的弯矩和剪力,易使中柱产生弯剪破坏;(4)本文结论可为地铁车站及其他地下结构的抗震设计提供借鉴。

摘要：多轮多支柱起落架飞机主起落架数量较多,试验机及试验设备重量大。试验应急卸载时,试验件和设备重量、以及加载过程中试验件变形所聚集能量快速释放的不协调性易对支持点结构产生较大冲击载荷,且该载荷不可控,影响试验的考核,存在安全隐患。针对多轮多支柱起落架飞机的强度试验要求,设计一种载荷限定系统。在应急卸载或者试验停试情况下,能够为非支持点起落架输出设定载荷,保证应急瞬间所产生的所有载荷按要求分配到所有起落架上,从而防止支持点起落架超载;试验过程中,能够对非支持点起落架施加试验主动载荷。利用仿真软件验证了系统原理的可行性。依据原理设计载荷限定系统,对其结构和工作性能进行应用验证,并在某型飞机全机疲劳试验中进行应用调试,结果表明,该系统完全能够满足试验要求。