摘要：Chunks, as fixed or semi-fixed structures, are the unity of grammar, semantics, and context which play an important role in the process of language comprehension and generation. This paper gives a brief introduction to the definition and classification of chunks, and makes an in-depth analysis of the use of chunks in 95 Chinese EFL learners’ compositions on the basis of the classification of chunks by Nattinger and DeCarrico. For the incorrect chunks in the compositions, this paper makes qualitative analysis and classifies them into redundancy, avoidance, tense, mixing, and chunks creation. According to the analysis, four suggestions on chunks teaching are put forward in order to explore effective measures to promote chunks teaching and help language learners improve their practical application ability of English.

摘要：Metaphor,as a systematic expression of human thinking,action and thought,is not only a form of language expression,but also a universal cognitive mode of human *** of Poetry,containing a large number of metaphors,is a classical work of human *** studying the metaphors in Book of Poetry,the thinking process of the people in the pre-Qin Dynasty can be fully *** on the conceptual metaphor theory of Lakoff and Johnson,taking Book of Poetry as the corpus,this paper aims to explore the plant metaphors in the *** to the different target domain,in this paper,the plant metaphors in Book of Poetry are classified into metaphors for virtue,for beautiful things,for blessing and for feeling,and some corresponding examples are used to elaborate *** study is of great significance to the appreciation and dissemination of Chinese classical *** the same time,by studying classical Chinese cultural works,the cross-language and cross-cultural characteristics of conceptual metaphor theory are proved.

摘要：本文从隐喻、转喻在认知语言学中的概念出发,选取了一些生活中常见且出色运用这种认知手段的Logo,通过分析隐喻和转喻在Logo设计中的运用,阐释了这种认知模式在产品Logo设计中的微妙效果。

摘要：针对三维空间中多航天器协同捕获机动目标问题,提出一种具有终端角度约束和时间一致性约束的设定时间协同制导律,将视线(Line-of-sight,LOS)角误差和齐射攻击的收敛时间作为一个可提前设定的参数,实现对收敛时间进行设置.构建三维场景航天器−目标运动学模型,在沿视线方向将同时攻击问题转化为一致性问题,提出一种分布式协同制导律,设定时间内使得多个航天器剩余飞行时间相等;在垂直视线方向利用滑模控制方法对制导律进行设计,使得每个航天器的视线角在设定时间内达到期望值.上述制导律中,设计了一种设定时间扩展状态观测器(Predefined-time extended state observer,PTESO)对未知的目标加速度进行估计.数值仿真结果验证了方法的有效性.

摘要：为了满足强激光系统对于合束光栅的宽带、高衍射效率及偏振无关的需求,本文提出了一种具有双层梯形结构的偏振无关合束光栅。首先,基于严格耦合波理论,建立了一种以粒子群优化算法为核心的偏振无关合束光栅设计模型,通过随机生成特征波长实现效率特性寻优。然后,详细分析了单层梯形和双层梯形结构光栅的槽深、占宽比、侧壁倾角等结构参数对光栅衍射效率及带宽的影响。最后,对两种结构光栅的电场增强特性进行分析讨论。结果表明,双层梯形结构偏振无关合束光栅在51 nm(1038~1089 nm)带宽范围内实现99%以上的理论衍射效率,相比传统单层梯形结构具有更大的工艺容差,容差范围内均满足30 nm带宽和98%的高衍射效率,同时具有更低的光栅近场增强,可以拥有更强的抗激光损伤能力。本文提出的宽带高衍射效率双层梯形结构光栅可以提高激光系统的输出功率,在激光合束领域具有重大的应用价值。

摘要：针对现有载人航天器空气过滤净化技术效率低、净化能力单一、易造成二次污染的问题,提出基于YMN_(2)O_(5)莫来石催化剂协同臭氧催化氧化的人机共存一体化技术路线。利用柠檬酸凝胶-溶胶法制备的YMN_(2)O_(5)催化剂通过X射线粉末衍射仪与扫描电子显微镜表征后发现,其表面具有丰富的活性位点,有利于在臭氧的协同作用下产生大量的还原性物质。该技术路线通过反应过程中产生的高活性O^(*),可对空气中挥发性有机化合物与病毒、细菌等微生物实现高效、绿色、低能耗的降解与消杀。基于此技术路线,结合3D建模与3D打印技术设计制作了空气净化和病毒消杀(Mcaton)一体化的原型机设备。针对空气中不同的挥发性有机污染物和病毒气溶胶,在密封舱内测试了原型机对气体污染物和病毒气溶胶的净化和消杀效果,验证了Mcaton技术可实现快速、高效净化各种挥发性有机污染物和病毒、细菌的消杀能力。

摘要：随着移动设备的广泛普及,其图形处理器的性能也逐渐增强.为了满足用户对卓越体验的不断追求,移动设备屏幕分辨率和刷新率每年都在不断提升.与此同时,移动游戏中的可编程绘制流水线也变得日益复杂,这导致游戏应用成为移动设备功耗的主要来源.研究了移动游戏中的绘制流水线,提出一种运动感知的绘制帧率调整方法,以在节能模式下保证绘制质量.与以往仅考虑历史帧绘制误差的预测模型不同,该方法通过建立摄像机位姿和帧间绘制误差的非线性关系模型,通过未来帧新的摄像机位姿预测其绘制误差,实现更为精确的帧率调整策略.此外,该方法还包括一个轻量级的场景识别模块,可根据玩家所处特定场景有针对性地调整误差阈值,从而采用不同程度的帧率调整策略.在定量对比上,相比只考虑历史帧误差的预测模型,构建的模型在游戏帧序列上的预测准确性提高30%以上.同时,在用户实验的定性对比上,相同跳帧比例下该方法能够得到用户体验更好的绘制效果.提出的算法融合了历史帧误差和摄像机位姿变化信息,能够预测出更准确的未来帧误差.算法结合预测结果和场景识别结果,实现了更好的动态帧率调整效果.

摘要：为研究时滞反馈对超磁致伸缩换能器输出的影响规律,扩大超磁致伸缩伸缩换能器的使用范围。通过分析换能器工作原理,建立时滞反馈控制下的系统动力学模型,采用多尺度法求解得到系统在位移、速度和加速度时滞反馈控制下的输出响应。仿真分析得知:无时滞反馈控制系统的输出呈硬式非线性特性;与无时滞反馈系统相比,位移和速度时滞反馈控制的换能器通过调整控制增益或时滞可有效降低系统的振动幅值、提高系统的稳定性;加速度时滞反馈控制下的换能器能够在不改变系统振幅的条件下改变系统的谐振频率,将加速度时滞反馈控制的换能器应用于能量回收系统中,仿真发现:调整控制增益不仅能够改变能量回收系统的有效频带范围,也可以调整系统的感应电压幅值。

摘要：当前博物馆教育引发热潮,但博物馆教育在高中阶段的开展还有所欠缺,且缺乏对学科内容的关注。以“硅酸盐材料”为例,在基于博物馆资源进行高中化学作业设计时,可以以大概念为线索,按照教学逻辑串联博物馆资源,基于文物的社会文化背景发展学科文化深度,利用第二课堂研学活动给予真实体验,基于数字化手段突破场域限制。

摘要：As a famous hole transporting material, nickle oxide (NiOx) has drawn enormous attention due to its low cost and superior stability. However, the relatively low conductivity and high-density surface trap states of NiOx severely limit device performance in solar cell applications. Interfacial engineering is an efficient approach to achieve remarkable hole-transporting performance by surface passivation. Herein, the efficient NiOx hole transport layer was prepared by surface passivation engineering strategy via facile solution processes with cesium iodide (CsI). It is demonstrated that CsI plays a super-effective dual-function role in inverted solar cell device: On one hand, the presence of CsI hugely passivates the surface trap states at the NiOx/perovskite interface along with obviously improved conductivity by the incorporated Cs^(+);on the other hand, the ions immigration is significantly suppressed by the presence of I ion for high-quality perovskite films, resulting in a stable contact interface. The ameliorative interface leads to largely reduced carrier non-radiative recombination, attributing to boosted carrier extraction efficiency. As a result, decent power conversion efficiency (PCE) of 18.48% with a noticeable fill factor (FF) beyond 80% was achieved. This facile and efficient surface engineering approach with dual-function shows excellent potential for the design of high-performance functional interfacial modification layer to achieve high-performance solar cells.