Robustly Tuning Bandgaps in Two-Dimensional Soft Phononic Crystals with Criss-Crossed Elliptical Holes

Tuning band gaps in soft materials by post-buckling deformation is becoming an appealing means to manipulate elastic waves. As one of the most favorable topologies, two- dimensional soft structures with circular holes have been extensively studied. Based on the contrarian thinking, this paper starts from the two-dimensional soft structures with criss-crossed elliptical holes, which is close to the post-buckling configuration of soft structures with circular holes, and then proposes to tune the band gaps through elongating or stretching rather than compressing. Influences of the loading magnitude and loading pattern （i.e., uniaxial and biaxial elongations） on the band gaps are studied via the nonlinear finite element simulations. Effects of the geometric parameters （the major-to-minor half-axis ratio and the porosity of the structure） are also discussed. It is shown that, compared with the traditional circular hole case, the band gaps of the unloaded structure with criss-crossed elliptical holes are much richer, and they could be reversely and continuously tuned by tensile loadings. In particular, the deformation is very robust and is insensitive to small geometric imperfections, which is always necessary for triggering the post-buckling deformations. The present work provides a useful reference to the manipula- tion of elastic waves in periodic structures as well as the design of soft phononic crystals/acoustic devices.

标准Criss-Cross剖分下线性有限元方程的快速AMG算法

首先对标准Criss -Cross剖分下的线性有限元空间进行能量正交分解 ,通过对正交子空间的双尺度分析 ,获得了一种合适的限制算子 ,进而构造相应的AMG算法 .数值实验结果表明 ,该方法对求解椭圆方程是非常有效和健壮的 ,且与通常的代数多重网格法相比较 。

一个新的线性规划Criss-cross算法(英文)

本文利用重新排列下标的技巧,提出了一个新的criss-cross算法.并证明了其有限性,理论分析及初步的计算实验表明,新算法比最小下标criss-cross算法效率更高.

Criss-Cross Attentional Siamese Networks for Object Tracking

Visual object tracking is a hot topic in recent years.In the meanwhile,Siamese networks have attracted extensive attention in this field because of its balanced precision and speed.However,most of the Siamese network methods can only distinguish foreground from the non-semantic background.The fine-tuning and retraining of fully-convolutional Siamese networks for object tracking(SiamFC)can achieve higher precision under interferences,but the tracking accuracy is still not ideal,especially in the environment with more target interferences,dim light,and shadows.In this paper,we propose crisscross attentional Siamese networks for object tracking(SiamCC).To solve the imbalance between foreground and non-semantic background,we use the feature enhancement module of criss-cross attention to greatly improve the accuracy of video object tracking in dim light and shadow environments.Experimental results show that the maximum running speed of SiamCC in the object tracking benchmark dataset is 90 frames/second.In terms of detection accuracy,the accuracy of shadow sequences is greatly improved,especially the accuracy score of sequence HUMAN8 is improved from 0.09 to 0.89 compared with the original SiamFC,and the success rate score is improved from 0.07 to 0.55.

Marie Corelli＇s The Secret Power in Bengali Rendering： Translation, Indianisation and Cultural Criss-crossing

Since the 1980s and 1980s, a new trend in the discipline of Translation Studies has emerged beyond the boundaries of Europe. Scholars from post-colonial nations like Canada, India, China, Africa, and Latin America have argued that translation was used in the past as a means of depriving the colonised people of their voice. In the colonial structure, the hegemonic culture used to dominate, making the others subservient. Translation in the colonial period reflected that hierarchy. In this light, decades after the independence of India, translation from a reverse direction, that is, rendering popular English texts in minority languages, may be seen as a process of＂writing back＂. Even if the original text concerned is not a ＂political＂ writing, and the translation is apparently meant for ＂safer-zones＂ such as ＂young students＇ literature＂, a tendency of claiming cultural equality, overlapping the translator＇s own cultural and literary heritage with the original author＇s, can be discovered. This paper attempts to focus on these issues in a particular text—the 1995 Bengali translation of Marie Corelli＇s 1921 science-fiction, The Secret Power. The purpose of this paper is to explore how Sudhindranath Raha has intermingled Biblical references and Western contexts with allusions to Indian culture and Sanskrit literature, thereby claiming a space for mutual understanding and respect between two cultures.

Superconvergence and asymptotic expansions for linear finite element approximations on criss-cross mesh

In this paper, we discuss the error estimation of the linear finite element solution on criss-cross mesh. Using space orthogonal decomposition techniques, we obtain an asymptotic expansion and superconvergence results of the finite element solution. We first prove that the asymptotic expansion has different forms on the two kinds of nodes and then derive a high accuracy combination formula of the approximate derivatives.

Intrinsically Viscoelastic Supramolecular Conjugated Polymer toward Suppressing Coffee-Ring Effect

The rational molecular design of light-emitting conjugated polymers that inherently suppress the ubiquitous coffee-ring effect(CRE)is a great challenge and the critical bottleneck for printing displays.Herein,we describe a supramolecular route to construct an intrinsically viscoelastic rigid conjugated polymer(RCP)(PHDPF-Cz)toward avoiding the CRE without sacrificing optoelectronic properties.Theπ-πstacking interactions derived fromthe pendant carbazole(Cz)units enable PHDPF-Cz to self-assemble into criss-cross nanofibers and endow its solutionwith great viscosity.Consequently,a high-quality and continuous PHDPFCz film was obtained by impeding the transport of aggregates to the droplet edge due to outward capillary flow during evaporation,in sharp contrast to the random aggregate migration and rapid precipitation generated fromthe controlled poly[4-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]-co-[5-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]and poly(9,9-dioctylfluorene)solutions.Finally,an efficient random laser is also achieved based on these cross-linked films with ultrastable single-chain excitonic behavior,confirming the effectiveness of our design strategy.