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111.
Six compounds were isolated from the fruits of Luffa cylindrica. They were identified as lucyosides C, E, F, H, a mixture of alpha-spinasterol and stigmasta-7,22,25-trien-3 beta-OH and a mixture of alpha-spinasteryl glucoside and delta 7,22,25-stigmasteryl-beta-D-glucoside by means of chemical evidence and spectral analysis. 相似文献
112.
计算机科学与技术专业是现代高校的必修专业,也是信息时代要求未来人才所必须具备的知识与技能。就我国目前高校中的计算机科学与技术的教学活动和培养现状来看,虽然取得了一定的成绩,但是还有很大的发展空间。本文中将提出一些对高校计算机科学与技术人才培养的建议。 相似文献
113.
Hui Chen Ping Lu Pengcheng Xiong Cheng-Zhong Xu Zhiping Wang 《Frontiers of Computer Science》2012,6(4):373-387
Both performance and energy cost are important concerns for current data center operators. Traditionally, however, IT and mechanical engineers have separately optimized the cyber and physical aspects of data center operations. This paper considers both of these aspects with the eventual goal of developing performance and power management techniques that operate holistically to control the entire cyber-physical complex of data center installations. Toward this end, we propose a balance of payments model for holistic power and performance management. As an example of coordinated cyber-physical system management, the energy-aware cyber-physical system (EaCPS) uses an application controller on the cyber side to guarantee application performance, and on the physical side, it utilizes electric current-aware capacity management (CACM) to smartly place executables to reduce the energy consumption of each chassis present in a data center rack. A web application, representative of a multi-tier web site, is used to evaluate the performance of the controller on the cyber side, the CACM control on the physical side, and the holistic EaCPS methods in a mid-size instrumented data center. Results indicate that coordinated EaCPS outperforms separate cyber and physical control modules. 相似文献
114.
115.
Bai Qingchun Wei Kai Zhou Jie Xiong Chao Wu Yuanbin Lin Xin He Liang 《The Journal of supercomputing》2021,77(9):9474-9493
The Journal of Supercomputing - Sentiment analysis in Danmaku video interaction aims at measuring public mood in respect of the video, which is helpful for the potential applications in behavioral... 相似文献
116.
Li Hongjian Wei Yaojun Xiong Yu Ma Enjie Tian Wenhong 《The Journal of supercomputing》2021,77(10):11575-11596
The Journal of Supercomputing - With the fast growth of big data applications, it has brought about a huge increase in the energy consumption for big data processing in Cloud data centers. In this... 相似文献
117.
Xu Qianqian Xiong Jiechao Cao Xiaochun Huang Qingming Yao Yuan 《International Journal of Computer Vision》2021,129(5):1732-1753
International Journal of Computer Vision - Nowadays, how to effectively evaluate visual properties has become a popular topic for fine-grained visual comprehension. In this paper we study the... 相似文献
118.
本文针对机械设备远程故障诊断的振动数据分析问题,设计了一种在Web浏览器中进行机械设备振动数据实时显示和频谱分析的方法。首先,LabVIEW程序通过以太网从工业现场采集实时振动数据并以网络共享变量发布;然后,LabVIEW Web Service服务程序根据用户请求获取实时振动波形数据或对数据进行频谱分析,将数据以XML方式返回;最后,客户端的浏览器中分别采用Flex和Ajax对XML进行解析并显示实时波形和特征参数。该方法快速、稳定、可靠,很好地解决了远程故障诊断的问题。 相似文献
119.
Liu Q Chen E Xiong H Ding CH Chen J 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2012,42(1):218-233
Recommender systems suggest a few items from many possible choices to the users by understanding their past behaviors. In these systems, the user behaviors are influenced by the hidden interests of the users. Learning to leverage the information about user interests is often critical for making better recommendations. However, existing collaborative-filtering-based recommender systems are usually focused on exploiting the information about the user's interaction with the systems; the information about latent user interests is largely underexplored. To that end, inspired by the topic models, in this paper, we propose a novel collaborative-filtering-based recommender system by user interest expansion via personalized ranking, named iExpand. The goal is to build an item-oriented model-based collaborative-filtering framework. The iExpand method introduces a three-layer, user-interests-item, representation scheme, which leads to more accurate ranking recommendation results with less computation cost and helps the understanding of the interactions among users, items, and user interests. Moreover, iExpand strategically deals with many issues that exist in traditional collaborative-filtering approaches, such as the overspecialization problem and the cold-start problem. Finally, we evaluate iExpand on three benchmark data sets, and experimental results show that iExpand can lead to better ranking performance than state-of-the-art methods with a significant margin. 相似文献
120.
Jiao Feng Naixue Xiong Laurence T. Yang Yan Yang 《Multimedia Tools and Applications》2012,56(2):227-243
With the advent of Next Generation Network (NGN), services that are currently provided by multiple specific network-centric
architectures. NGN provides AAA (Anytime, Anywhere and Always on) access to users from different service providers with consistent
and ubiquitous provision of services as necessary. This special issue of NGN includes pervasive, grid, and peer-to-peer computing
to provide computing and communication services at anytime and anywhere. In fact, the application of NGN includes digital
image processing, multimedia systems/services, and so on. Here we focus on the digital image processing technology in NGN
environments. Low-contrast structure and heavy noise in NGN environments can be found in many kinds of digital images, which
makes the images vague and uncertainly, especially in x-ray images. As result, some useful tiny characteristic are weakened—which
are difficult to distinguish even by naked eyes. Based on the combination of no-linear grad-contrast operator and multi-resolution
wavelet analysis, a kind of image enhancement processing algorithm for useful tiny characters is presented. The algorithm
can enhance the tiny characters while confine amplifying noise. The analysis of the results shows that local regions of the
image are enhanced by using the concept of the grad contrast to make image clearer adaptively. Experiments were conducted
on real pictures, and the results show that the algorithm is flexible and convenient. 相似文献