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151.
概述了汽车顶内饰用热塑性聚氨酯硬质泡沫塑料进展状况,介绍了硬泡及顶内饰成型方法,对影响该硬泡性能的一些因素进行了讨论。指出该顶内饰已批量生产。 相似文献
152.
P3软件是一套体现了现代化项目管理理念的项目管理工具,在建设管理上推广应用P3工程管理软件,可以提高各参建单位的工作效率、加快工程信息交流、数据共享和工程进度管理水平,在管理上尽快与国际接轨,本文就P3软件在电力基建工程中的应用做以简单介绍。 相似文献
153.
An extremely simple and compact planar monopole ultrawideband (UWB) slot antenna with dual band‐notched characteristics is proposed. The antenna is composed of a circular radiation patch, a microstrip‐fed line, and a partial ground. By etching an arc‐shaped slot on the radiation patch and a C‐like slot on the feed line, dual notched frequency bands at 3.3–3.7 GHz for WiMAX and 5.15–5.825 GHz for WLAN are achieved. And, the two notched bands can be adjusted independently by varying the length of the slots. Moreover, the band‐notched characteristics can be reconfigurable by shorting the corresponding slots. So, the antenna is capable of operating in one of multiple modes which makes it an excellent candidate for UWB applications. Meanwhile, experimental results indicate that the antenna has an available impendence bandwidth from 2.9 to 11 GHz which covers the UWB frequency band, and nearly omnidirectional patterns, stable gains, small group delay in operating band except rejected bands. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:706–712, 2014. 相似文献
154.
This paper presents a unified framework for automatically detecting and tracking dim small targets in infrared (IR) image sequence under complex backgrounds. Firstly, the variance weighted information entropy (variance WIE) followed by a region growing technique is introduced to segment the candidate targets in a single-frame IR image after background suppression. Then the pipeline filter is used to verify the real targets. The position and the size of the detected target are then obtained to initialize the tracking algorithm. Secondly, we adopt an improved local binary pattern (LBP) scheme to represent the target texture feature and propose a joint gray-texture histogram method for a more distinctive and effective target representation. Finally, target tracking is accomplished by using the mean shift algorithm. Experimental results indicate that the proposed method can effectively detect the dim small targets under complex backgrounds and has better tracking performance compared with the gray histogram based tracking methods such as the mean shift and the particle filtering. 相似文献
155.
Graft copolymerization of acrylic acid (AA) onto polyphenylene sulfide (PPS) nonwoven initiated by low temperature plasma was studied. The effects of various conditions on graft reaction and the grafting rate were investigated. SEM images showed that PPS nonwoven was grafted, and the graft copolymerization only occurred on the surface of PPS. It may be due to the chain transference going with the graft copolymerization. It was found that with the increasing of plasma power, treatment time, space between electrodes, monomer concentration, and temperature of graft polymerization, the grafting rate increased at first, went to the top, and then decreased. The PPS nonwoven surface graft reaction could be optimized by the following processing conditions: 120 s of plasma treatment time, 50 W of plasma power, 1.5 cm of space between electrodes, 30% (w/w) of monomer concentration, and 50°C of temperature of graft polymerization. Measurement of XPS showed that the peak of C1s of graft polyacrylic acid was existed, and the peak area increased with the increase of the grafting rate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5884–5889, 2006 相似文献
156.
In this paper, remote information concentration is investigated which is the reverse process of the $1\rightarrow 3$ optimal asymmetric economical phase-covariant telecloning (OAEPCT). The OAEPCT is different from the reverse process of optimal universal telecloning. It is shown that the quantum information via $1\rightarrow 3$ OAEPCT procedure can be remotely concentrated back to a single qubit with a certain probability via several quantum channels. In these schemes, we adopt Bell measurement to measure the joint systems and use projected measurement and positive operator-valued measure to recover the original quantum state. The results shows non-maximally entangled quantum resource can be applied to information concentration. 相似文献
157.
158.
罚函数法是一种将约束优化问题转化为无约束问题的重要方法.对于一般的约束优化问题,通过加入新参数,给出了一种改进的精确罚函数和这种罚函数的精确罚定理证明,提出了求解这种罚函数的算法.实验表明该算法是有效的. 相似文献
159.
以纳米SiOx为改性材料,采用浇铸工艺制备了纳米SiOx/环氧树脂复合材料。探讨了纳米复合材料的分散工艺方法以及不同的纳米SiOx含量对复合材料力学性能和耐热性能的影响。结果表明,当纳米材料质量分数为1%时,复合材料的分散效果好,拉伸强度和断裂伸长率提高到3倍,无缺口冲击强度达11.6kJ/m^2,洛氏硬度和耐热性能也有提高。 相似文献
160.
Dynamic mechanical analysis and differential scanning calorimetry were used to investigate the relaxations and crystallization of high‐density polyethylene (HDPE) reinforced with calcium carbonate (CaCO3) particles and an elastomer. Five series of blends were designed and manufactured, including one series of binary blends composed of HDPE and amino acid treated CaCO3 and four series of ternary blends composed of HDPE, treated or untreated CaCO3, and a polyolefin elastomer [poly(ethylene‐co‐octene) (POE)] grafted with maleic anhydride. The analysis of the tan δ diagrams indicated that the ternary blends exhibited phase separation. The modulus increased significantly with the CaCO3 content, and the glass‐transition temperature of POE was the leading parameter that controlled the mechanical properties of the ternary blends. The dynamic mechanical properties and crystallization of the blends were controlled by the synergistic effect of CaCO3 and maleic anhydride grafted POE, which was favored by the core–shell structure of the inclusions. The treatment of the CaCO3 filler had little influence on the mechanical properties and morphology. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3907–3914, 2007 相似文献