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81.
Zihe Li Xiangming Feng Liwei Mi Jinyun Zheng Xiaoyang Chen Weihua Chen 《Nano Research》2018,11(8):4038-4048
Spinel LiMn2O4 is a widely utilized cathode material for Li-ion batteries. However, its applications are limited by its poor energy density and power density. Herein, a novel hierarchical porous onion-like LiMn2O4(LMO) was prepared to shorten the Li+ diffusion pathway with the presence of uniform pores and nanosized primary particles. The growth mechanism of the porous onion-like LiMn2O4 was analyzed to control the morphology and the crystal structure so that it forms a polyhedral crystal structure with reduced Mn dissolution. In addition, graphene was added to the cathode (LiMn2O4/graphene) to enhance the electronic conductivity. The synthesized LiMn2O4/graphene exhibited an ultrahigh-rate performance of 110.4 mAh·g–1 at 50 C and an outstanding energy density at a high power density, maintaining 379.4 Wh·kg–1 at 25,293 W·kg–1. Besides, it shows durable stability, with only 0.02% decrease in the capacity per cycle at 10 C. Furthermore, the (LiMn2O4/graphene)/graphite full-cell exhibited a high discharge capacity. This work provides a promising method for the preparation of outstanding, integrated cathodes for potential applications in lithium ion batteries. 相似文献
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84.
Xin Ma Xinlong Xu Zheng Zheng Kun Wang Yalin Su Jiangfeng Fan Rui Zhang Lusheng Song Zhiyou Wang Jinsong Zhu 《Sensors and actuators. A, Physical》2010,157(1):9-14
An electro-optically modulated intensity interrogation method based on tunable waveguide coupled surface plasmon resonance sensors has been proposed. It has been theoretically and experimentally demonstrated that the proposed scheme can enable sensitive measurement of measurand variations. By modulating the refractive index in the waveguide layer, this interrogation method yields modulated signal whose amplitude is related to measurand's refractive index. This amplitude modulated signal offers a higher signal to noise ratio and eliminates additive noise in the sensor system. A preliminary investigation using saline buffers with different NaCl concentrations shows a resolution of 2.3 × 10?6 refractive index unit by our approach. Resolution can be controlled by the amplitude of the applied modulation voltage and can be further enhanced by optimizing the device structure or improving the electro-optical (E-O) coefficient of the E-O material. This approach is simple, stable, and promising for low-cost or multi-channel SPR biosensor applications. 相似文献
85.
Zheng Zheng Wei Liu Kai-Yuan Cai 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(12):1339-1348
In many applications, such as intelligent decision systems, there are usually random perturbations caused by the constant changing of real situations, thus the analysis of the robustness with respect to random perturbations is practically important. In the side of fuzzy methods, a corresponding problem arises: will a small random perturbation of fuzzy input cause a big variance of fuzzy output? This paper study the robustness of fuzzy schemes in environments with random perturbations. It focuses on fuzzy algebraic operators, and proposes two methods to analyze their robustness in environments with random perturbations. The effectiveness and features of the methods are shown by simulations. 相似文献
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Ruijuan Zheng Mingchuan Zhang Qingtao Wu Shibao Sun Jiexin Pu 《International Journal of Information Security》2010,9(1):1-17
With the rapid development of network technologies and deteriorating of network environment, traditional single-net security
system cannot satisfy the security requirement. The excellent security performance of biological systems impels the bio-inspired
network security theory to be a hot research area currently. Based on Bio-inspired Multidimensional Network Security Model
we have put forward, we have advanced Bio-inspired Multi-Net Security system by implementing the functional distribution of
different subnets of different transient states in Multi-Net Paralleling structure. Firstly, parameter estimation and modified
algorithms of Hidden Markov Model are introduced to construct the mathematical mode of B-MNS; secondly, the integrated performance
of our modified B-MNS has been tested and its simulation has been carried out. So the feasibility, validity and high efficiency
of our model have been demonstrated theoretically, and practically. 相似文献
88.
磁悬浮系统是复杂的强耦合系统,研究中未充分考虑轨道的弹性形变,会造成磁浮列车和轨道之间产生耦合振动的现象,而考虑这一因素对系统的影响无疑增加了研究的难度;为了便于问题的求解,采用非线性系统理论解耦的方法,对单电磁铁悬浮系统进行纵向解耦控制,并对解耦后的子系统进行极点配置使其满足要求的性能指标;仿真结果表明该方法有效地使复杂问题简单化,并且能够实现系统的全局稳定和良好的动态性能. 相似文献
89.
“Emergency medicine” is the front line of medical service a hospital provides; also it is the department people seek medical care from immediately after an emergency happens. The statistics by the Department of Health, Executive Yuan, indicate that over years, the number of people at the emergency department has been increasing. The US has introduced and practiced the triage system in the emergency medicine in 1960, whereby to aid the emergency department in allocating the patients, to give them appropriate medical care by the fast decision of the nurses and doctors in case of the patients’ seriousness through their judgment.This study takes on the knowledge contained in the massive data of unknown characteristics in the triage database at a Taiwanese regional hospital, using the cluster analysis and the rough set theory as tools for data mining to extract, with the analysis software ROSE2 (Rough Sets Data Explorer) and through rule induction technique, the imprecise, uncertain and vague information of rules from the massive database, and builds the model that is capable of simplifying massive data while maintaining the accuracy in classifying rules. After analyzing and evaluating the knowledge obtained from relevant mining in the hospitals past medical data for the consumption of emergency medical resources, this thesis proposes suggestions as reference for the hospitals in subsequent elevation of medical quality and decrease in operative costs. 相似文献
90.