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Multimedia Tools and Applications - Tree species classification is a necessary and challenging task for both multimedia technique and forestry engineering. Continuous developments in multimedia and... 相似文献
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Multimedia Tools and Applications - The sampling-based matting method is an important method for image matting. There are three key techniques in sampling-based matting: 1) how to build a... 相似文献
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割缝预抽后煤瓦斯吸附特性的变化特征 总被引:1,自引:0,他引:1
为了研究割缝预抽后煤瓦斯吸附特性的变化特征,以杨柳煤矿10煤层7个煤样为研究对象,采用甲烷等温吸附实验测定煤样的Langmuir方程吸附常数a和b,通过压汞实验和低温液氮吸附实验的有机结合,表征煤样孔径分布和比表面积的变化.结果表明:(1)随着煤样与割缝孔距离的增大,吸附常数α呈逐渐增大的趋势,而吸附常数b的变化趋势则相反,但与甲烷等温吸附曲线的曲率变化趋势一致.(2)随着煤样与割缝孔距离的增大,煤样孔径分布发生显著的变化,吸附孔孔容比从33.27%增大到55.38%,比表面积从7.254 m2/g增大到9.856 m2/g.(3)割缝预抽后,煤样参数曲线(Langmuir方程吸附常数、吸附孔孔容比和比表面积)的变化幅度均呈现出平缓→急剧→平缓的趋势,具有有界性和非线性的特征,符合Boltzmann方程.割缝预抽后煤瓦斯吸附特性的变化存在明显的分区特征:变化显著区(小于1.8 m)、变化过渡区(1.8~4.5 m)和变化不显著区(大于4.5 m).(4)割缝预抽后煤体瓦斯压力下降,有效应力增大,进而控制煤体的吸附特性.研究结果可以为煤层水力割缝增透实践提供可靠的基础理论支撑. 相似文献
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Railway Engineering Science - Bus rapid transit (BRT) systems have been shown to have many advantages including affordability, high capacity vehicles, and reliable service. Due to these attractive... 相似文献
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This paper presents a novel tracking algorithm which integrates two complementary trackers. Firstly, an improved Bayesian tracker(B-tracker) with adaptive learning rate is presented. The classification score of B-tracker reflects tracking reliability, and a low score usually results from large appearance change. Therefore, if the score is low, we decrease the learning rate to update the classifier fast so that B-tracker can adapt to the variation and vice versa. In this way, B-tracker is more suitable than its traditional version to solve appearance change problem. Secondly, we present an improved incremental subspace learning method tracker(Stracker). We propose to calculate projected coordinates using maximum posterior probability, which results in a more accurate reconstruction error than traditional subspace learning tracker. Instead of updating at every time, we present a stopstrategy to deal with occlusion problem. Finally, we present an integrated framework(BAST), in which the pair of trackers run in parallel and return two candidate target states separately. For each candidate state, we define a tracking reliability metrics to measure whether the candidate state is reliable or not, and the reliable candidate state will be chosen as the target state at the end of each frame. Experimental results on challenging sequences show that the proposed approach is very robust and effective in comparison to the state-of-the-art trackers. 相似文献
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提出一种基于软件定义网络架构的大批量高能物理科学数据交换虚拟专用网思想,构建跨地域的高能物理实验合作单位之间SDN架构网络,设计数据传输智能路径选择算法,利用充足的IPv6链路资源服务于高能物理科学数据传输,解决大批量高能物理科学数据传输需求对现有网络带宽不足的压力,保障高能物理科学数据在合作单位之间高速、稳定、安全地传输。 相似文献
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研究从发酵小麦制酒精残渣中提取分离出的寡肽抗氧化和免疫活性。将112 只4 周龄雌性健康昆明小鼠随机分成14 组,基础对照组和实验1~6组饲喂正常基础料的同时分别灌胃生理盐水、低、中、高3 个剂量的寡肽(五肽和七肽),高脂对照组和实验7~12组饲喂高脂料的同时分别灌胃生理盐水、低、中、高3 个剂量的寡肽(五肽和七肽),连续灌胃28 d后,测定基础对照组和实验1~6组血清中丙二醛(malondialdehyde,MDA)含量,肝匀浆中MDA含量、超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)和谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性,脾脏中淋巴T细胞CD3+、CD4+和CD8+数量,测定基础对照组、高脂对照组和实验7~12组十二指肠、空肠和回肠中MDA含量、SOD、CAT、GSH-Px活性。结果显示,与高脂对照组相比,灌胃寡肽后,血清、肝脏和肠道中MDA含量显著下降(P<0.05),SOD、CAT、GSH-Px活性显著升高(P<0.05),CD4+/CD8+显著升高(P<0.05)。结果表明寡肽均具有体内抗氧化能力和免疫活性,而且能够清除高脂饮食带来的氧化损伤。 相似文献
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纳米材料构建的化学修饰电极用于多巴胺电化学检测已经被广泛研究。当前电极研究策略主要为采用复合材料并构建三维结构以增大吸附表面积。本综述总结了目前常用的纳米碳修饰材料与纳米金属修饰材料,比较分析了其表面结构形貌对多巴胺吸附的影响及吸附机制,总结了目前常用的构建三维修饰电极的方法。分析结果表明,相对于一维形貌,三维形貌结构的修饰电极往往具有更好的检测能力,三维结构不仅能显著增大表面积,提供更多的吸附位点,还可能产生“薄膜效应”,该效应在一定程度上能提高响应灵敏度,但超过一定限度会减缓响应时间,第一性原理分析表明,多巴胺在纳米修饰电极材料表面的吸附机制是化学吸附。最后指出了在改进修饰电极结构设计合理性、增强抗干扰性和提高选择性,以及新的检测控制机制分析方面需要进一步研究。 相似文献