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991.
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993.
在全耗尽绝缘体上硅(FDSOI)衬底上制备了一种新型隧穿场效应晶体管(TFET),并用相似的工艺方法制备金属-氧化物-半导体场效应晶体管(MOSFET)作为比较,分别基于两种器件构成基本电流镜电路,研究两种器件的基本性能和电路电流传输能力.两种器件均采用杂质分凝技术制备,在源漏与沟道的界面形成了陡峭的杂质分布,TFET也因此具备陡峭的隧穿结.两种器件的载流子输运机制不同,因此温度对电流的影响也不同,此外,不同于MOSFET的单极导通行为,TFET由于源漏两端均为重掺杂,表现为强烈的双极导通行为.测试发现,由TFET构成的电流镜电路的电流传输比高达97%,高于一般的TFET电流镜和实验中用于对比的MOSFET电流镜,且TFET电流镜的输出阻抗较高,约1 MΩ.这为TFET的研发与简单应用提供了参考. 相似文献
994.
Analysis and modeling of task scheduling in wireless sensor network based on divisible load theory 下载免费PDF全文
Liang Dai Zhong Shen Ting Chen Yilin Chang 《International Journal of Communication Systems》2014,27(5):721-731
In this paper, we propose a novel task scheduling algorithm (Divisible Task scheduling Algorithm for Wireless sensor networks (DTAW)) based on divisible load theory in heterogeneous wireless sensor networks to complete the tasks within the shortest possible time and reduce the sensors' energy‐consuming. In DTAW, the tasks are distributed to the wireless sensor network by the (SINK) on the basis of the processing and communication capacity of each sensor. After receiving the subtasks, the intracluster sensors carry out its tasks simultaneously and send the results to cluster head sequentially. By removing communication interference between each sensor, reduced task completion time and improved network resource utilization are achieved. Each cluster head simultaneously finishes sending fused data to the SINK after fusing the data obtained from intracluster sensors. In this way, the overlap between the task performing and communication phase would be much better. Simulation results are presented to demonstrate the impacts of different network parameters on the makespan and energy consumption. The results show that the algorithm enables to reasonably distribute tasks to each sensor and then effectively reduces the time‐consuming and energy‐consuming. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
995.
MMSE‐based transceiver design for distributed MIMO amplify‐and‐forward cooperative networks in correlated channels 下载免费PDF全文
Chia‐Chang Hu Wei‐Yu Liang Guan‐Yi Li 《International Journal of Communication Systems》2014,27(10):1686-1701
In this paper, the source‐precoder, multiple‐relay amplifying matrices, and destination‐equalizer joint optimization is investigated in distributed MIMO amplify‐and‐forward multiple‐relay networks with direct source–destination transmission in correlated fading channels. With the use of taking both the direct link and spatial correlation between antenna elements into account, the cooperative transceiver joint design is developed based on the minimum mean‐squared error criterion under individual power constraints at the source and multiple‐relay nodes. Simulation results demonstrate that the cooperative transceiver joint design architecture for an amplify‐and‐forward MIMO multiple‐relay system outperforms substantially the noncooperative transceiver design techniques on the BER performance under the spatial‐correlation channels.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
996.
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
997.
Runsheng Gao Jie Tang Xiaoliang Yu Shiqi Lin Kun Zhang Lu‐Chang Qin 《Advanced functional materials》2020,30(27)
Silicon‐based materials have shown great potential and been widely studied in various fields. Unlike its unparalleled theoretical capacity as anodes for batteries, few investigations have been reported on silicon‐based materials for applications in supercapacitors. Here, an electrode composed of layered silicon‐based nanosheets, obtained through oxidation and exfoliation, for a supercapacitor operated up to 4 V is reported. These silicon‐based nanosheets show an areal specific capacitance of 4.43 mF cm?2 at 10 mV s?1 while still retaining a specific capacitance of 834 µF cm?2 even at an ultrahigh scan rate of 50 000 mV s?1. The volumetric energy and power density of the supercapacitor are 7.65 mWh cm?3 and 9312 mW cm?3, respectively, and the electrode can operate for 12000 cycles in a potential window of 4 V at 2 A g?1, while retaining 90.6% capacitance. These results indicate that the silicon‐based nanosheets can be a competitive candidate as the supercapacitor electrode material. 相似文献
998.
Conception of Stretchable Resistive Memory Devices Based on Nanostructure‐Controlled Carbohydrate‐block‐Polyisoprene Block Copolymers 下载免费PDF全文
Chih‐Chien Hung Yu‐Cheng Chiu Hung‐Chin Wu Chien Lu Cécile Bouilhac Issei Otsuka Sami Halila Redouane Borsali Shih‐Huang Tung Wen‐Chang Chen 《Advanced functional materials》2017,27(13)
It is discovered that the memory‐type behaviors of novel carbohydrate‐block ‐polyisoprene (MH‐b ‐PI) block copolymers‐based devices, including write‐once‐read‐many‐times, Flash, and dynamic‐random‐access‐memory, can be easily controlled by the self‐assembly nanostructures (vertical cylinder, horizontal cylinder, and order‐packed sphere), in which the MH and PI blocks, respectively, provide the charge‐trapping and stretchable function. With increasing the flexible PI block length, the stretchability of the designed copolymers can be significantly improved up to 100% without forming cracks. Thus, intrinsically stretchable resistive memory devices (polydimethylsiloxane(PDMS)/carbon nanotubes(CNTs)/MH‐b ‐PI thin film/Al) using the MH‐b ‐PI thin film as an active layer is successfully fabricated and that using the MH‐b ‐PI12.6k under 100% strain exhibits an excellent ON/OFF current ratio of over 106 (reading at ?1 V) with stable V set around ?2 V. Furthermore, the endurance characteristics can be maintained over 500 cycles upon 40% strain. This work establishes and represents a novel avenue for the design of green carbohydrate‐derived and stretchable memory materials. 相似文献
999.
6‐Mercaptopurine‐Induced Fluorescence Quenching of Monolayer MoS2 Nanodots: Applications to Glutathione Sensing,Cellular Imaging,and Glutathione‐Stimulated Drug Delivery 下载免费PDF全文
Shih‐Chiang Chen Chang‐Yu Lin Tian‐Lu Cheng Wei‐Lung Tseng 《Advanced functional materials》2017,27(41)
Molybdenum disulfide (MoS2) nanodots (NDs) with sulfur vacancies have been demonstrated to be suitable to conjugate thiolated molecules. However, thiol‐induced fluorescence quenching of MoS2 NDs has been rarely explored. In this study, 6‐mercaptopurine (6‐MP) serves as an efficient quencher for the fluorescence of monolayer MoS2 (M‐MoS2) NDs. 6‐MP molecules are chemically adsorbed at the sulfur vacancy sites of the M‐MoS2 NDs. The formed complexes trigger the efficient fluorescence quenching of the M‐MoS2 NDs due to acceptor‐excited photoinduced electron transfer. The presence of glutathione (GSH) efficiently triggers the release of 6‐MP from the M‐MoS2 NDs, thereby switching on the fluorescence of the M‐MoS2 NDs. Thus, the 6‐MP‐M‐MoS2 NDs are implemented as a platform for the sensitive and selective detection of GSH in erythrocytes and live cells. Additionally, thiolated doxorubicin (DOX‐SH)‐loaded M‐MoS2 NDs (DOX‐SH/M‐MoS2 NDs) serve as GSH‐responsive nanocarriers for DOX‐SH delivery. In vitro studies reveal that the DOX‐SH/M‐MoS2 NDs exhibit efficient uptake by HeLa cells and greater cytotoxicity than free DOX‐SH and DOX. In vivo study shows that GSH is capable of triggering the release of DOX‐SH from M‐MoS2 ND‐based nanomaterials in mice. It is revealed that the DOX‐SH/M‐MoS2 NDs can be implemented for simultaneous drug delivery and fluorescence imaging. 相似文献
1000.