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1.
随着社交媒体的发展,用户之间的关系网络对于社交媒体的分析有很大的帮助。因此,该文主要研究用户好友关系检测。以往的关于用户好友关系抽取的研究主要基于社交媒体上的结构化信息,比如其他好友关系,用户的不同属性等。但是,很多时候用户本身并没有大量的好友信息存在,同时也不一定有很多确定的属性。因此,我们希望基于用户发表的文本信息来对用户关系进行预测。不同于以往的潜在好友推荐算法,该文提出了一种基于注意力机制以及长短时记忆网络(long short-term memory,LSTM)的好友关系预测模型,将好友之间的评论分开处理,通过分析用户之间的评论来判断是否具备一定的好友关系。该模型将好友双方信息拼接后的结果作为输入,并将注意力机制应用于LSTM的输出。实验表明,用户之间的评论对于好友关系预测确实有较大的实际意义,该文提出的模型较之于多个基准系统的效果,取得了明显的提升。在不加入任何其它非文本特征的情况下,实验结果的准确率达到了77%。 相似文献
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易前 《水利水电工程设计》2006,25(4):12-13
镜面混凝土是水电工程建设中新兴的一门施工技术,在乌江索风营水电站地下厂房岩锚梁混凝土施工中采用了镜面混凝土,这在技术上是一次大胆的尝试和创新,既满足了功能上的要求,同时也达到了美观和装饰地下厂房的效果,为今后水电工程施工中广泛采用镜面混凝土技术提供了样本和宝贵经验。 相似文献
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裂解炉炉管基于风险的检验 总被引:4,自引:2,他引:2
管式裂解炉炉管受炉内高温及管内介质压力的共同作用,易发生蠕变等现象,因此,对裂解炉炉管进行风险评价尤为重要。应用API 581基于风险的检验规范对炉管的失效可能性及失效后果分别进行定量计算,并由此得到裂解炉炉管的定量风险结果和基于风险的检验周期,为裂解炉的风险控制与管理提供依据。 相似文献
6.
迷宫螺旋泵和密封工作特性研究 总被引:1,自引:1,他引:0
介绍了一种实测迷宫螺旋泵和密封工作特性的实验方法,通过该方法可以测得迷宫螺旋泵的泵送特性曲线、迷宫螺旋端面组合密封的最大密封压力以及端面开启的开始转速,具有一定的实用价值。 相似文献
7.
Uplink scheduling in wireless systems is gaining importance due to arising uplink intensive data services (ftp, image uploads
etc.), which could be hampered by the currently in-built asymmetry in favor of the downlink. In this work, we propose and
study algorithms for efficient uplink packet-data scheduling in a CDMA cell. The algorithms attempt to maximize system throughput
under transmit power limitations on the mobiles assuming instantaneous knowledge of user queues and channels. However no channel
statistics or traffic characterization is necessary. Apart from increasing throughput, the algorithms also improve fairness
of service among users, hence reducing chances of buffer overflows for poorly located users.
The major observation arising from our analysis is that it is advantageous on the uplink to schedule “strong” users one-at-a-time,
and “weak” users in larger groups. This contrasts with the downlink where one-at-a-time transmission for all users has shown
to be the preferred mode in much previous work. Based on the optimal schedules, we propose less complex and more practical
approximate methods, both of which offer significant performance improvement compared to one-at-a-time transmission, and the
widely acclaimed Proportional Fair (PF) algorithm, in simulations. When queue content cannot be fed back, we propose a simple modification of PF, Uplink PF (UPF), that offers similar improvement.
Hereafter, we refer to users with low recieved power at the base even when transmitting at peak transmit power as “weak” users,
and the strongly recieved users at the base as “strong” users.
Krishnan Kumaran is currently a member of the Complex Systems Modeling section in the Corporate Strategic Research of ExxonMobil Corp., Clinton,
NJ. Formerly, he was a Member of Technical Staff in the Mathematics of Networks and Systems Research Department at Bell Labs
in Murray Hill, NJ, where his research interests were in modeling, analysis and simulation of design, resource management
and scheduling issues in telecommunication networks.
Lijun Qian is an assistant professor in the Department of Electrical Engineering at Prairie View A&M University. He received his B.S.
from Tsinghua University in Beijing, M.S. from Technion-Israel Institute of Technology, and Ph.D. from WINLAB, Rutgers University,
all in electrical engineering. Before joining PVAMU, he was a researcher at Networks and Systems Research Department of Bell
Labs in Murray Hill, NJ. His major research interests are in wireless communications and networking technologies, especially
in radio resource management, protocol design, TCP/RLP optimization and MPLS traffic engineering. 相似文献
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世界原油质量趋势及我国面临的挑战 总被引:3,自引:0,他引:3
评述了世界原油质量趋势、我国重质油现状以及我国加工含硫原油的现状和前景。 相似文献
10.
Layered Wyner-Ziv video coding. 总被引:2,自引:0,他引:2
Following recent theoretical works on successive Wyner-Ziv coding (WZC), we propose a practical layered Wyner-Ziv video coder using the DCT, nested scalar quantization, and irregular LDPC code based Slepian-Wolf coding (or lossless source coding with side information at the decoder). Our main novelty is to use the base layer of a standard scalable video coder (e.g., MPEG-4/H.26L FGS or H.263+) as the decoder side information and perform layered WZC for quality enhancement. Similar to FGS coding, there is no performance difference between layered and monolithic WZC when the enhancement bitstream is generated in our proposed coder. Using an H.26L coded version as the base layer, experiments indicate that WZC gives slightly worse performance than FGS coding when the channel (for both the base and enhancement layers) is noiseless. However, when the channel is noisy, extensive simulations of video transmission over wireless networks conforming to the CDMA2000 1X standard show that H.26L base layer coding plus Wyner-Ziv enhancement layer coding are more robust against channel errors than H.26L FGS coding. These results demonstrate that layered Wyner-Ziv video coding is a promising new technique for video streaming over wireless networks. 相似文献