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101.
102.
罗雄 《数码设计:surface》2009,(9):104-106
数字不仅作为一种文化现象在传播,而且作为一种符号也被高效率地再表现和再认识,它是视觉传达设计中的设计元素。本文试从数字在东西方的释义及数字在设计作品中的应用及其审美介绍入手,阐述数字在视觉传达设计中的重要性。 相似文献
103.
基于模板法的网页英语试卷自动抽取技术的研究 总被引:1,自引:1,他引:0
为解决在线考试系统中建立海量数据库的问题,采用基于模板法的Web信息抽取方法,提取相似网页中的正文内容。并根据包含英文试卷的网页特点,制定正文抽取规则,最终可获得完整的英语试卷及其答案。实验结果表明,该方法具有较高的准确率和提取速度。 相似文献
104.
边坡监测是大坝安全监测的一个重要方面,边坡监测的自动化是一种必然的发展趋势。针对边坡监测的特点以及边坡监测常用的传感器的特点,设计了一种基于CAN总线控制系统的大坝边坡安全监测模块。该模块采用C8051f040作为CPU,AD620作为放大器,AD7710作为AD转换芯片,并进行了抗干扰、防雷击、防潮以及环境适应方面的设计。实验证明该模块测量精度能够满足水利系统的要求,而且具有长期稳定性,对环境的适应性等方面则有待该系统在青海拉西瓦大坝的现场实验中得到验证。 相似文献
105.
本设计给出大容量闪存卡CF及文件系统在采煤机振动检测中的应用.介绍了CF卡的基本结构和工作原理,实现了系统软硬件的设计.采用CF卡做媒介,将检测到的大量数据按FAT16格式记录并存入CF卡,为后续采煤机故障诊断及改进设计打下了基础. 相似文献
106.
107.
Chuanming Tian Bin Li Yichuan Rui Hao Xiong Yu Zhao Xuefei Han Xinliang Zhou Yu Qiu Wei An Kerui Li Chengyi Hou Yaogang Li Hongzhi Wang Qinghong Zhang 《Advanced functional materials》2023,33(41):2302270
Despite the outstanding power conversion efficiency (PCE) of perovskite solar cells (PSCs) achieved over the years, unsatisfactory stability and lead toxicity remain obstacles that limit their competitiveness and large-scale practical deployment. In this study, in situ polymerizing internal encapsulation (IPIE) is developed as a holistic approach to overcome these challenges. The uniform polymer internal package layer constructed by thermally triggered cross-linkable monomers not only solidifies the ionic perovskite crystalline by strong electron-withdrawing/donating chemical sites, but also acts as a water penetration and ion migration barrier to prolong shelf life under harsh environments. The optimized MAPbI3 and FAPbI3 devices with IPIE treatment yield impressive efficiencies of 22.29% and 24.12%, respectively, accompanied by remarkably enhanced environmental and mechanical stabilities. In addition, toxic water-soluble lead leakage is minimized by the synergetic effect of the physical encapsulation wall and chemical chelation conferred by the IPIE. Hence, this strategy provides a feasible route for preparing efficient, stable, and eco-friendly PSCs. 相似文献
108.
Ziyi Guo Junyao Zhang Xu Liu Lu Wang Lize Xiong Jia Huang 《Advanced functional materials》2023,33(46):2305508
Both photodetectors (PDs) and optoelectronic synaptic devices (OSDs) are optoelectronic devices converting light signals into electrical responses. Optoelectronic devices based on organic semiconductors and halide perovskites have aroused tremendous research interest owing to their exceptional optical/electrical characteristics and low-cost processability. The heterojunction formed between organic semiconductors and halide perovskites can modify the exciton dissociation/recombination efficiency and modulate the charge-trapping effect. Consequently, organic semiconductor/halide perovskite heterojunctions can endow PDs and OSDs with high photo responsivity and the ability to simulate synaptic functions respectively, making them appropriate for the development of energy-efficient artificial visual systems with sensory and recognition functions. This article summarizes the recent advances in this research field. The physical/chemical properties and preparation methods of organic semiconductor/halide perovskite heterojunctions are briefly introduced. Then the development of PDs and OSDs based on organic semiconductor/halide perovskite heterojunctions, as well as their innovative applications, are systematically presented. Finally, some prospective challenges and probable strategies for the future development of optoelectronic devices based on organic semiconductor/halide perovskite heterojunctions are discussed. 相似文献
109.
Shixiong Yao Xingjian Tian Jiageng Chen Yi Xiong 《International Journal of Network Management》2023,33(3):e2193
Smart grid has drawn a lot of attention and investment in recent years, which not only helps the modern generation and distribution of traditional power but also highly widens the application of renewable energy sources. However, the main challenges in the application of smart grid are 1. the privacy preservation of users' information and 2. the trustful transmission channel among peers. In order to solve these problems, VPN and blockchain can be considered since they have some features perfectly suitable for these situations. In this paper, we propose a smart grid system based on WireGuard and Hyperledger Fabric to solve the problems mentioned above. And we also implement the whole system and give a view by web application. What's more, all the functionalities are displayed and tested, including building a smart device simulator, deploying data visualization and making some performance evaluations about transactions and WireGuard communication. Experiment results show that the introduction of WireGuard into network infrastructure does not cause too much loss of bandwidth and delay, but it ensures a certain degree of communication security. And Fabric provides the consistency and traceability of transactions in smart grid system. 相似文献
110.
Chunsan Deng Yuncheng Liu Xuhao Fan Binzhang Jiao Zexu Zhang Mingduo Zhang Fayu Chen Hui Gao Leimin Deng Wei Xiong 《Advanced functional materials》2023,33(11):2211473
Intelligent micromachines that respond to external light stimuli have a broad range of potential applications, such as microbots, biomedicine, and adaptive optics. However, artificial light-driven intelligent micromachines with a low actuation threshold, rapid responsiveness, and designable and precise 3D transformation capability remain unachievable to date. Here, a single-material and one-step 4D printing strategy are proposed to enable the nanomanufacturing of agile and low-threshold light-driven 3D micromachines with programmable shape-morphing characteristics. The as-developed carbon nanotube-doped composite hydrogel simultaneously enhanced the light absorption, thermal conductivity, and mechanical modulus of the crosslinked network, thus significantly increasing the light sensitivity and response speed of micromachines. Moreover, the structural design and assembly of asymmetric microscale mechanical metamaterial unit cells enable the highly efficient additive nanomanufacturing of 3D shape-morphable micromachines with large dynamic modulation and spatiotemporal controllability. Using this strategy, the world's smallest artificial beating heart with programmable light-stimulus responsiveness for the cardiac cycle is successfully printed. This 4D printing method paves the way for the construction of multifunctional intelligent micromachines for bionics, drug delivery, integrated microsystems, and other fields. 相似文献