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921.
Controlled Incorporation of Ni(OH)2 Nanoplates Into Flowerlike MoS2 Nanosheets for Flexible All‐Solid‐State Supercapacitors 下载免费PDF全文
Chunxue Hao Fusheng Wen Jianyong Xiang Limin Wang Hang Hou Zhibin Su Wentao Hu Zhongyuan Liu 《Advanced functional materials》2014,24(42):6700-6707
In this work, self‐supporting three‐dimensional hierarchical nanostructured MoS2@Ni(OH)2 nanocomposites are synthesized via a facile single‐mode microwave hydrothermal technique. The fabricated MoS2@Ni(OH)2 nanocomposites for supercapacitors in aqueous electrolyte exhibit higher specific capacitance and better cyclic stability than those of MoS2 and Ni(OH)2 due to the pronounced synergistic effect between MoS2 and Ni(OH)2. Further, the flexible all‐solid‐state supercapcitor is readily constructed by composing the PVA/KOH gel electrolyte in between two MoS2@Ni(OH)2 electrodes on the flexible PET substrates. The resulting supercapacitors can operate at high rate up to 1000 V/s, have excellent long‐life cycling stability, retaining 94.2% of the initial capacitance after 9000 cycles, and mechanical flexibility during extreme bending, respectively. Thereby, the MoS2@Ni(OH)2 nanocomposites are a promising electrode materials for flexible long‐life cycling all‐solid‐sate supercapacitors. 相似文献
922.
Mehmet Emir Koksal 《Mathematical Methods in the Applied Sciences》2019,42(16):5274-5292
After introducing the concept of commutativity for continuous‐time linear time‐varying systems, the related literature and the results obtained so far are presented. For a simple introduction of the commutativity of discrete‐time linear time‐varying systems, the problem is formulated for first‐order systems. Finally, explicit necessary and sufficient conditions for the commutativity of first‐order discrete‐time linear time‐varying systems are derived, and their advantageous use in digital system design is illustrated, which are the main objectives of the paper. The results are verified by examples which include an application in amplitude modulation for digital telecommunication. 相似文献
923.
Yang Shao Xiang Xiao Longyan Wang Yang Liu Shengdong Zhang 《Advanced functional materials》2014,24(26):4170-4175
This paper reports that the electrical, optical and structural properties of ITO film can be significantly modulated by an anodization treatment. An ITO TFT technology based on the anodization approach is then proposed and demonstrated, which results in an ideal homo‐junction device structure with the source/drain/pixel electrodes and channel region made of one single ITO layer. A preliminary device fabrication at room temperature shows the resulting TFT has an on/off current ratio exceeding 1 × 108, a saturation mobility of 29.0 cm2 V?1 s?1, and a subthreshold swing of 0.20 V per decade. This technology also allows a feasible VT adjustment and muti‐VT implementation. 相似文献
924.
Daniel Discini Silveira José de Souza Lima Maurício Silveira 《International Journal of Communication Systems》2014,27(12):4346-4354
For the fast prototyping, production, and delivery of commercial radio frequency products/systems, accurate and reliable test systems are necessary. These systems are usually product customized and thus expensive solutions, capable of performing all necessary measurements for a specific product. The purpose of this paper is to present a flexible cost‐effective test solution, capable of realizing all necessary measurement on a high output power amplifier system greater than 500 W, and to generate essential reports. These reports allow the system operator to (i) perform an analysis and a statistical comparison among various products, assuring that the quality is the same for all products; and (ii) retain products that present a performance poorer than other similar products, without a rigorous technical analysis, thus increasing efficiency in factory assembly line. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
925.
Digital rights management system with user privacy,usage transparency,and superdistribution support 下载免费PDF全文
Chih‐Ta Yen Horng‐Twu Liaw Nai‐Wei Lo 《International Journal of Communication Systems》2014,27(10):1714-1730
In the modern world, digital content has been massively produced, distributed, and consumed by human beings; consequently, how to protect the rights and benefits of content consumers, producers, and distributors has become a crucial issue. One promising solution is to design a full‐fledged digital rights management (DRM) system. In this study we introduce a new design on the digital rights management system providing user privacy, usage transparency, and superdistribution. A comprehensive set of DRM processing functions and corresponding mechanisms are developed in our system to support various business process requirements. Superdistribution support is embedded in our system design. A prototype is implemented to verify our system design. To protect consumer privacy, a temporary identity is generated for each consumer using the KryptoKnight protocol. Elliptic curve cryptography‐based encryption scheme is adopted for messages transmitted among servers and client over an unsecure communication channel. For usage transparency, a user‐friendly DRM client package (software) is introduced in the proposed DRM system to achieve content protection and support user convenience in usage.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
926.
The source authentication is an important issue for the multicast applications because it can let the receiver know whether the multicast message is sent from a legal source or not. However, the previously related schemes did not provide the confidentiality for data packets. In addition, the communication costs of these schemes are still high for real‐time applications in the multicast environments. To solve the aforementioned problems, we propose a new source authentication scheme based on message recovery signature for multicast in this paper. In the proposed scheme, the encrypted data can be embedded in the digital signature, so the communication loads can be greatly reduced. In addition, the digital signature contains the encrypted data, and thus the confidentiality of data packets can be well protected. According to the aforementioned advantages, the proposed scheme is securer and more efficient than the related works for the real‐time applications. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
927.
阐述数字微波通信的系统结构及数字微波通信系统的组成,并通过对PDH与SDH数字传输体制的比较分析来根据实际情况确定所要采用的传输模式,同时说明本站系统升级改造的必要性。 相似文献
928.
新型高精度电子计重仪是一款全新的高精度的全自动计重仪器,它主要由称重传感器,16位单片机控制模块,AD转换模块,数码管显示模块,交流稳压电源五部分组成。针对目前广大的市场,我们有针对性地开发出这套有实用价值的电子秤系统。从技术上克服诸多缺点,改善电子秤系统在应用中的不足之处,具有现实意义。 相似文献
929.
调幅是中短波广播中一种主要的调制方式。本文针对现有的模拟短波AM解调器的不足,提出了一种基于FPGA的全数字解调器。其最大的优点是将系统中的模拟电路压缩到最小。短波信号在前端经过模数转换器采样后直接送给FPGA处理,有效的避免了过多的模拟电路对系统指标的影响。 相似文献
930.