摘要：In this paper,a design method for an acoustic cloak in the presence of background mean flows is proposed by using topology optimization,which enables the associated fabrication of the cloaking *** density-based topology optimization method is used to allocate the designated materials,thus providing the structure of the *** optimization problem is efficiently solved with the gradient-based globally convergent method of moving asymptotes,which utilizes the derivative information from the finite element simulation studies of the linearized acoustic potential *** paper introduces the whole design method first then numerically demonstrates the corresponding performance,which shall constitute the main contribution of the present work.

摘要：In this work,the classical single cart-pole dynamic system is extended to the double cart-pole dynamic system with the inclusion of a competing target,which enables the study of multi-agent deep learning problems at an affordable *** corresponding important issues,such as system dynamics,reward function and simultaneous training of opponent agents,are discussed in *** showcase the system dynamics,a couple of agents are trained and the analysis of the competing results reveals the key pattern for winning the *** appears that a defensive agent is always defeated by an offensive agent,albeit the associated neural network has a very limited *** both agents are defensive,the system dynamics will remain stable and achieve the Nash ***,the proposed dynamic system could serve a surrogate model and assist the study about how to escape the so-called Thucydides trap.

摘要：Electrochemical water splitting is regarded as the most promising approach to produce ***,the sluggish electrochemical reactions occurring at the anode and cathode,namely,the oxygen evolution reaction(OER)and the hydrogen evolution reaction(HER),respectively,consume a tremendous amount of energy,seriously hampering its wide ***,single-atom catalysts(SACs)have been proposed to effectively enhance the kinetics of these two *** this minireview,we focus on the recent progress in SACs for OER and HER *** classes of SACs have been reviewed,i.e.,alloy-based SACs,carbon-based SACs and SACs supported on other *** factors affecting the activities of SACs are also highlighted,including the inherent element property,the coordination environment,the geometric structure and the loading amount of metal ***,we summarize the current problems and directions for future development in SACs.

摘要：“无场景,不产品”,场景体现了产品的使用价值,但却鲜少有涉及产品场景及相关属性配置的研究。在线评论中蕴含丰富的用户使用场景及与其相匹配产品特征的用户需求偏好信息,对这些信息的挖掘日益成为企业基于用户开展产品创新的关键。针对既有研究有效数据集中度低、模型识别精度差及未考虑产品使用场景等问题,设计了基于词的Tf-LSTM特定场景下的用户需求识别模型。通过词库构建、无效信息筛除、特征关注度计算、情感分类模型构建以及场景-特征与用户情感倾向的结合,为企业了解用户需求及改进产品提供了明确方向。太平洋汽车网用户生成内容的实验表明,本文情感分类模型的准确率、精确率和F1分别为92.8%、93.3%、93.0%,优于KNN、SVM、RNN、BERT等模型分类效果,场景-特征-情感的关联分析及特征改进优先级划分也为产品的创新改进指明了方向。

摘要：广告设计追求自然、原创、简洁而又富有震撼性的艺术魅力,无疑值得艺术设计者认真探究。本文以"简洁并非简单"的创意思维原则,对广告设计所给予人们视觉上的魅力享受进行了阐述。

摘要：利用遗传修饰技术可以使动物在遗传水平发生改变,实现在个体内表达外源基因或对其内源基因的功能造成影响。在动物育种中,可以利用遗传修饰技术在分子水平进行设计并实现品种的快速改良。从传统的遗传修饰技术、病毒载体、精子载体等介导的遗传修饰技术到新型人工核酸酶介导的基因编辑技术,尤其是CRISPR/Cas9为代表的人工核酸酶的运用使得基因编辑动物的制备变得更加高效快捷,并迅速在多个物种中得到应用。这些方法也已经拓展到了绵羊(Ovis aries)遗传育种领域。利用遗传修饰技术在绵羊中进行分子育种比传统的育种方式具有更大的优势,可以使用多种策略直接对性状进行快速改良,并且可以加快育种进程。本文详细介绍了遗传修饰技术在绵羊中的研究历程,探讨了通过遗传修饰技术进行绵羊分子设计育种的可能性,并提出以上技术和方法在绵羊育种中面临的问题和挑战。

摘要：阐述"少就是多、简洁而不简单"包装创意设计理念的主张和原则,在设计商品包装中,追求自然、平实、雅达、简洁而有意境的包装设计风格,无疑是包装创意设计者值得认真探究的问题。

摘要：随着动漫产业的高速发展,其人才的培养也越来越受到业界和相关部门的高度重视。高校作为培养动漫人才的重要基地,是发展动漫产业与培养动漫人才的孵化器,文章针对高校培养动漫人才教育问题进行了讨论,并提出了若干对策建议。

摘要：为了解决智能车辆在轨迹跟踪过程中存在模型参数不确定、建模误差及外界干扰导致的跟踪精度及行驶稳定性变差的问题,本文提出了一种基于横纵向双预瞄PID补偿的智能车辆运动控制方法。首先,基于路径跟踪误差模型建立了线性二次型调节器(Linear Quadratic Regulator,LQR)横向运动控制器,以预瞄点横向偏差为输入量,通过横向预瞄PID控制器实现转角补偿;其次,基于不依赖模型的模糊理论设计了纵向运动控制器实现车速跟踪,以预瞄点的纵向偏差为输入量,通过建立预瞄PID控制器进行车速补偿;最后,通过匀加速双移线工况对该方法进行了仿真验证。仿真结果表明,基于横纵向双预瞄PID补偿的智能车辆运动控制器在高速、大曲率的双移线工况具备更高的跟踪精度和行驶稳定性。

摘要：针对突发疫情带来的患者线下交叉感染风险与医护人工排查患者工作量激增的社会公共安全问题,通过文献法、流行病学理论、专家咨询与主观赋权法(医院感控、呼吸内科、危急重症科、疾病控制中心等部门的专家)、人机交互设计、用户测试与可用性评估等方法,进行了突发疫情疑似症状风险自查内容、可供选项、风险权重与阈值以及人机交互设计研究,制定了疑似病案筛查与患者分类居家观察、隔离和立即就诊的早期防控策略,设计了疑似症状风险评估人机交互应用与筛查模式并上线推广使用.结果表明在突发疫情爆发早期,疑似症状风险自查应用为民众提供了简单易行的临床判断科学依据,一定程度上缓解了民众盲目焦虑、线下交叉感染风险以及医护人工排查工作量,为未来新型传染病疫情防控,提供了线上疑似症状风险筛查分类与线下患者分流就医的防控策略与人机交互设计参考.