Subdivision based isogeometric analysis for geometric flows

We present a new isogeometric analysis (IGA) approach based on extended Loop subdivision scheme for solving various geometric flows defined on subdivision surfaces. The studied flows include the second-order, fourth-order, and sixth-order geometric flows, such as averaged mean curvature flow, constant mean curvature flow, and minimal mean-curvature-variation flow, which are generally derived by minimizing the associate energy functionals with $L^2$-gradient flow respectively. The geometric flows are discretized by means of subdivision based IGA, where the finite element space is formulated by the limit form of the extended Loop subdivision for different initial control meshes. The basis functions, consisting of quartic box-splines corresponding to each subdivided control mesh, are utilized to represent the geometry exactly. For the cases of the evolution of open surfaces with any shape boundary, high-order continuous boundary conditions derived from the mixed variational forms of the geometric flows should be implemented to be consistent with the isogeometric concept. For time discretization, we adopt an adaptive semi-implicit Euler scheme. By several numerical experiments, we study the convergence behaviors of the proposed approach for solving the geometric flows with high-order boundary conditions. Moreover, the numerical results also show the accuracy and efficiency of the proposed method.     

Memory-based dynamic event-triggered control for networked interval type-2 fuzzy systems subject to DoS attacks

In this article, the memory-based dynamic event-triggered controller design issue is investigated for networked interval type-2 (IT2) fuzzy systems under non-periodic denial-of-service (DoS) attacks. For saving limited network bandwidth, a novel memory-based dynamic event-triggered mechanism (DETM) is proposed to schedule data communication. Unlike existing event-triggered generators, the developed memory-based DETM can utilize a series of newly released signals and further save network resources by introducing interval dynamic variables. Moreover, to improve design flexibility, an IT2 fuzzy controller with freely selectable fuzzy rule number and premise membership functions (MFs) is synthesized. Then, a new switched time-delay system with imperfectly matched MFs is established under the consideration of memory-based DETM and DoS attacks simultaneously. Besides, based on the property of MFs, the boundary information of membership grades and slack matrices are introduced in the stability analysis. Furthermore, by using a piecewise Lyapunov–Krasovskii method, membership-functions-dependent criteria are deduced to ensure the asymptotic stability of built fuzzy switched systems. Finally, the effectiveness of proposed control strategies is demonstrated by simulation examples.     

泸县6.0级地震文化遗产震害调查与分析

2021年9月16日，四川省泸县发生6.0级地震，对当地的文化遗产造成了不同程度的损坏。为掌握文化遗产在此次地震中的破坏情况，对古建筑、古桥、渡槽、摩崖造像、古遗址以及可移动文物进行震害调查，分析破坏原因，提出不同文化遗产的震害等级，并统计其在此次地震中破坏占比。研究结果表明：古建筑中木结构的震害较轻，砖木结构和石木结构的损伤较为严重，表现为墙体开裂、倾斜、倒塌和屋面损毁等破坏；古桥的桥面板产生裂缝和起壳，桥头堡基石发生移位；摩崖造像发生开裂、石像脱落，部分岩石发生坠落；古遗址的原有缝隙增大，石砌墙歪闪或倾斜；可移动文物与陈列台连接的金属卡件在地震下崩落。根据震害调查结果，将文化遗产的震害划分为4个等级，并对古建筑的维修与加固、摩崖造像的一体化监测、古桥的维护与应急抢险、可移动文物的隔震保护提出几点建议，为我国文化遗产的抗震保护提供参考。     

稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业应用

介绍了浙江石油化工有限公司新建的3 Mt/a柴油加氢精制装置，其配套使用中国石化石油化工科学研究院有限公司开发的催化剂级配技术，并实施了可根据原料供应及市场产品需求情况灵活调整切换的2种生产技术方案。1 a的安稳生产运行结果表明:该装置以直馏柴油为主原料，通过分馏塔的馏分切割及其侧线抽出，实现了稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业化应用；在实施以兼产喷气燃料为主的生产技术方案时，通过调整常一线柴油的掺炼量，不仅可以生产含硫量小于10.0 μg/g的精制柴油产品，同时兼产所得到的喷气燃料产品含硫量小于0.5 μg/g，赛波特颜色号值大于30；在实施主产精制柴油组分方案时，通过掺炼质量分数为20%~40%的催化柴油，并使所提炼得到的精制柴油组分含硫量小于6.0 μg/g的前提下，这些精制柴油组分产品既可直接作为满足国Ⅵ柴油产品出厂待售，也可作为柴油调和组分储存待用于产品的进一步优化。     

Quantum State Sharing Under Noisy Environment

International Journal of Theoretical Physics - Quantum state sharing (QSS) plays significant role in transmitting quantum secret information. However, in practical quantum communication situation,...     

安卓平台上的医用图像信息采集系统的开发设计

为了探讨在安卓平台上构建医用图像采集系统的开发个案,分析通过以智能手机、平板电脑为核心安卓设备通过拍照获得化验单数据后进行文本识别并提交智慧医疗系统的解决方案。本文首先通过二值化算法形成低阈值图像数据,使用卷积神经元网络算法对文本进行逐一识别,使用K-means算法对识别后的单字文本进行字段记录值的整合并形成元数据库服务于其他智慧医疗系统模块。在使用9000组数据对神经元网络进行前期训练的前提下,该系统的识别准确率达到了99.5%以上。本系统具有一定的可行性,对未来智慧医疗的系统开发有实践意义。     

M2M energy saving strategy in 5G millimeter wave system

Telecommunication Systems - Machine to Machine technology has a broad application prospect in the 5G network, but there is a bottleneck in the energy consumption of intelligent devices powered by...