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11.
采用Qt的嵌入式版本,即Qt/E,在DM6446的软件系统平台MontaVista Linux上进行视频GUI应用程序开发,充分利用了DM6446的在屏显示(OSD)模块的硬件特性,实现了在视频层上叠加GUI窗口层的视频叠加显示方法。视频数据的更新主要由硬件模块负责,避免了软件进行视频格式转换的CPU耗时,提高了视频显示的效率。应用程序目标平台上能够实现视频的实时采集和高效显示,说明Qt/E在DM6446中进行视频GUI开发具有实用性。  相似文献   
12.
The preparation and evaluation of 30# hard grade asphalt by blending softening point hard deoil asphalt with several soft components were investigated. The results showed that the properties and proportions of blending soft components had a great influence on the properties of 30# asphalt. Chunfeng 70# asphalt and Maoming deoil asphalt were more suitable as blending soft components and their blended asphalt met the technical requirements of GB/T 15180-2010 when the proportion of hard deoil asphalt were 6–12% and 8–16%, respectively. PG grade results indicated that dynamic modulus of 30# asphalts at high temperature increased significantly, and antirutting ability was also improved notably, while the bending resistant ability at low temperature was slightly inferior to the high-grade asphalt. The results of mix performance tests showed that 30# hard grade asphalt had excellent anti–high-temperature deformation ability and preferable water stability compared with high-grade asphalts.  相似文献   
13.
Composite modified hard asphalt (CMHA) was prepared by four-step high-speed shearing method adding crumb rubber, styrene-butadiene-styrene (SBS) copolymer, and hard asphalt to QHD AH-70 neat asphalt. The high-temperature performance and microstructure of CMHA were evaluated by rotational viscometer, fluorescence microscopy, and infrared spectroscopy, through which the modification mechanism was proposed. The results show that the shearing time had great influence on the high-temperature performance of CMHA. A significant variation in phase morphology of CMHA during preparation was observed. It is found that phase morphology was converted from a continuous asphalt phase with dispersed polymer phase to two twisted continuous phases, then to a continuous asphalt phase with dispersed polymer phase again. Preparation of CMHA was a complex physical and chemical process. A fraction of SBS took part in the chemical reaction and others were dispersed in net structure, which is beneficial for workability and performance of asphalt.  相似文献   
14.
A dose of SBR modifier added to asphalt can improve asphalt's performance in stability, permanence, viscosity, and resistance to aging. Better application performances of asphalt pavement are affected directly by proper SBR modifying. This paper shows some investigations that confirm the relationship between the addition of SBR with the structure and the properties of SBR-modified asphalt. This paper also discusses the modified asphalt high temperature property, low temperature ductility, and mechanism of SBR-modified asphalt. The addition of SBR modifier showed an increase in viscosity, softening point, and elastic recovery of modified asphalt with rising temperature. When the temperature rises, the improvement of SBR-modified asphalt in softening point, elastic recovery, and visco-toughness result from SBR cross-linking. Although the lengths of low temperature ductility of SBR-modified asphalt are increased, the viscosities of modified asphalt increase; however, the softening point between the upper layer and lower layer were about 1.8°C after the isolated experiment.  相似文献   
15.
In order to solve the problems related with processing low-quality Liaohe highly sour crude, the Liaohe Petrochemical Company has explored the possibility in optimizing the processing of highly sour crude by adopting different process schemes depending upon the properties of the highly sour crude. The Liaohe naphthenic-base crude oil with low freezing point is earmarked for manufacture of naphthenic lube oils and heavy traffic paving asphalt, while the extra-heavy Liaohe crude with high acid number is routed directly to delayed coking unit coupled with corresponding corrosion preventing measures, resulting in tackling the problem of equipment corrosion arising from refining of Liaohe highly sour crude to obtain light distillates from Liaohe heavy crude through a short process scheme.  相似文献   
16.
This work describes a novel location‐aware, self‐organizing, fault‐tolerant peer‐to‐peer (P2P) overlay network, referred to as Laptop. Network locality‐aware considerations are a very important metric for designing a P2P overlay network. Several network proximity schemes have been proposed to enhance the routing efficiency of existing DHT‐based overlay networks. However, these schemes have some drawbacks such as high overlay network and routing table maintenance overhead, or not being completely self‐organizing. As a result, they may result in poor scalability as the number of nodes in the system grows. Laptop constructs a location‐aware overlay network without pre‐determined landmarks and adopts a routing cache scheme to avoid maintaining the routing table periodically. In addition, Laptop significantly reduces the overlay maintenance overhead by making each node maintain only the connectivity between parent and itself. Mathematical analysis and simulations are conducted to evaluate the efficiency, scalability, and robustness of Laptop. Our mathematical analysis shows that the routing path length is bounded by logd N, and the joining and leaving overhead is bounded by d logd N, where N is the number of nodes in the system, and d is the maximum degree of each node on the overlay tree. Our simulation results show that the average latency stretch is 1.6 and the average routing path length is only about three in 10 000 Laptop nodes, and the maximum degree of a node is bounded by 32. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
17.
针对机载电子全姿态指引仪显示图形信息的特征及其变化特点,在系统初始化时将图形内容分为背景层、填充层和动态字符层三层,运算过程中只改变根据参数变化的填充层和字符层;将图形运算过程分为图形轮廓生成和硬件区域填充,分别由DSP软件标记区域边界,FPGA根据标记硬件完成区域填充;同时图形运算处理算法在所设计的DSP+FPGA的硬件平台上进行了实现与验证,结果表明,这种图形处理方法减轻了传统处理方法中主处理器的运算负担,很大程度上提高了系统的实时性。  相似文献   
18.
王仕果  纪红 《中国通信》2010,7(2):120-126
 在无线信道环境下,如何解决逻辑拓扑与物理拓扑之间的失配是设计P2P网络的主要挑战之一。本文提出一种适用于无线系统的P2P组网协议。在该协议中,首先,新入网节点从其邻居节点处获得一个数值上相近的节点标号,从而实现网络的瞬时拓扑感知。当节点的位置改变时,它们向中心节点更新自己的位置信息。然后,在中心节点处将节点标号的最优分配转换为旅行商问题,并用模拟退火算法对旅行商问题进行最优化求解,得到优化标号序列。最后,由中心节点向网络广播更新信息,引导节点进行标号和数据交换,从而使无线P2P网络在任何时刻都具有拓扑感知性。仿真结果表明,在基于该协议的无线P2P网络中,文件的定位路径明显缩短,定位延时明显减小。  相似文献   
19.
Zhu Liang  Li Jie  Zhou Congshu  Gu Yili  Yang Huayue 《半导体学报》2009,30(6):066002-066002-5
For thick resist implant layers, such as a high voltage P well and a deep N well, systematic and uncorrectable overlay residues brought about by the tapered resist profiles were found. It was found that the tapered profile is closely related to the pattern density. Potential solutions of the manufacturing problem include hardening the film solidness or balancing the exposure density. In this paper, instead of focusing on the process change methodology,we intend to solve the issue of the overlay metrology error from the perspective of the overlay mark design. Based on the comparison of the overlay performances between the proposed overlay mark and the original design, it is shown that the optimized overlay mark target achieves better performance in terms of profiles, dynamic precision,tool induced shift (TIS), and residues. Furthermore, five types of overlay marks with dummy bars are studied, and a recommendation for the overlay marks is given.  相似文献   
20.
加强农村广播电视的发展,提高其覆盖率是关键,针对这一问题,阐述了解决农村广播电视覆盖的手段,对农村广播电视覆盖现状做了详细的分析,并提出建议和措施。  相似文献   
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