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91.
《Nano Research》2016,(8):2478-2486
Single wall carbon nanotubes (SWNTs) are known for their exceptional electronic properties.However,most of the synthesis methods lead to the production of a mixture of carbon nanotubes having different chiralities associated with metallic (m-SWNTs) and semiconducting (s-SWNTs) characteristics.For application purposes,effective methods for separating these species are highly desired.Here,we report a protocol for achieving a highly selective separation of s-SWNTs that exhibit a fundamental optical transition centered at 1,550 nm.We employ a polymer assisted sorting approach,and the influence of preparation methods on the optical and transport performances of the separated nanotubes is analyzed.As even traces of m-SWNTs can critically affect performances,we aim to produce samples that do not contain any detectable fraction of residual m-SWNTs. 相似文献
92.
A methodology for optimal control of the polymer electrolyte membrane fuel cell (PEMFC) with multiple criteria is presented here. In this regard, thermoelectric objectives and thermoeconomic objective are considered, simultaneously. The proposed fuel cell is a 1200 W Ballard PEMFC namely Nexa? power module. The net power density and exergetic efficiency of the PEMFC are maximized, and the unit cost of the generated power is minimized in a multi‐objective optimization procedure using the NSGA‐II (non‐dominated sorting genetic algorithm). Operating temperature and pressure, air stoichiometric coefficient at the cathode and the current density are considered as controlling parameters in order to acquire optimal performance of the PEMFC. A set of optimal solution namely the Pareto frontier is obtained, and a final optimal solution is selected from available solutions located on the Pareto frontier using the fuzzy decision‐making process based on the Bellman–Zadeh approach. Results are compared with corresponding results obtained previously in single objective optimization scenarios. It has been shown that the optimal operating condition obtained based on the multiple criteria approach has least deviation from the ideal features of the fuel cell in comparison to the corresponding optimal solution obtained in conventional single‐objective optimization approaches. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
93.
针对目前PLC系统对同材质、同体积零件的分拣困难,提出了给PLC系统引入视觉技术的方法。利用DDE技术将Matlab与PLC结合一起,共同完成平面零件的识别和分拣。Matlab主要完成零件图像的获取和比对识别,并将识别结果传送给PLC,而PLC则根据所接收到的识别结果,控制气缸动作,完成多种结构复杂零件的分拣任务。 相似文献
94.
订单拣选是配送中心最费时费力的环节,配送速度不仅是新型电商的核心竞争力也是大型制造企业物料配送的核心指标,复合式拣选策略成为提高配送速度的重要方式。结合复合式拣选方式中货物之间不同的出货要求,将货物按照出货的紧急程度进行分类,建立了以能耗成本、作业时间以及出货惩罚值最小化为目标的堆垛机拣选作业序列多目标优化模型。通过改进带精英策略的非支配排序遗传算法(NSGA-Ⅱ)实现该问题的高效求解。算例分析表明,复合式拣选策略下可实现大多数订单的提前拣选,改进优化算法可为决策者在成本、效率和服务质量3个维度提供科学决策依据。 相似文献
95.
Ore sorting is a useful tool to remove gangue material from the ore of bigger size ranges. The radical development in the area of artificial intelligence allows speedy processing the full color digital images for the preferred investigations. In this paper a novel approach to classify the ores for ferromanganese metallurgical plant feed has been proposed based on the visual texture of the ore particles (Mn, Fe, and Al2O3 rich) and radial basis neural network. The visual texture of ore particles vary with the mineral contents. This information can be quantified by using image processing technique in RGB color space and, first and second-order statistical analysis. Commonly used Hartlic’s textural features was calculated and presented as neural network inputs along with red, green and blue color values for 5 × 5 pixel size windowpanes extracted from three separate images. Results obtained show encouraging accuracy to apply the approach to develop an expert system for on line ore quality monitoring to control the ore blending in the feed ore circuits as well as separating gangue minerals present in the feed ores. Matlab® 7.0 was used for visual textural analysis and neural network classification. 相似文献
96.
通过调查深圳龙岗现有城市生活垃圾分类现状和收运模式,分析其存在的问题和成因,提出深圳市龙岗区生活垃圾分类处理的策略。 相似文献
97.
98.
《Ergonomics》2012,55(12):1553-1560
Abstract Using a sample of 54 Hong Kong Chinese subjects a highly significant correlation was found between lobe area and search performance on a task where the stimulus presentation was controlled with a semi-automatic electro-mechanical ‘card changer’. By using the same stimulus material for determination of lobe size and search performance and by reducing the possibility of subjects using extreme search strategies, a 90s manual card sorting test was found to correlate significantly with the ‘card changer’ results and with lobe area. The good correlation with lobe area was obtained for a homogeneous group of subjects with respect to age and near acuity using a rapid and simple method of lobe area measurement. The visual lobe is a function of considerable importance for visual search and has been shown to be related to search performance in a variety of practical situations. It is suggested here that a card sorting task may be used to assess the relative extent of a person's visual lobe size for screening individuals involved in search tasks, or to assess the effects of training. 相似文献
99.
The paper presents several sorting methods of γ-ray events which were implemented in the data acquisition, processing and visualization system, developed at the Institute of Physics of the Slovak Academy of Sciences. The sorting methods using various shapes of gates (conditions) are presented, including rectangular windows, polygons, gates defined by arithmetic functions, spherical, ellipsoidal and composed gates. The examples illustrating the use of these methods are presented as well. 相似文献
100.
传统的脉冲序列跟踪器都是纯硬件的,用单片机是一种全新的偿试。本文论述了用MCS-96十六位单片机构成的脉冲序列跟踪器的设计要点,以及该跟踪器的特点。 相似文献