一种基于变分多跳图注意力编码器的深层协同真值发现

大数据时代,数据价值的释放经常需要融合多源数据,数据冲突成为这一过程中无法避免的关键问题。为了从冲突数据中筛选出真实声明以及可靠数据源,研究人员提出了真值发现方法。然而,现有的真值发现大多注重数据源与声明之间的直接协同信息,忽略了更深层的间接协同与对抗信息,导致不足以表达出数据源与声明的特征。针对此问题,提出了基于变分多跳图注意力编码器的真值发现方法(TD-VMGAE),基于数据源与声明之间的包含关系构建二分图网络,采用多跳图注意力层为每个节点表征汇聚间接协同信息以及对抗信息,并设计真值发现变分自编码器,抽取节点表征中所需的分类分布,对数据源和声明进行协同分类。实验结果表明,所提方法在3个不同尺度的数据集中均有不错的表现,消融实验和可视化也验证了所提方法的有效性和泛化能力。

一种基于节点异质性降低跳图维护代价的方法

Skip Graphs提供了一种新的P2P查找算法,但是其系统查询和维护的消息流量巨大,限制了其应用.本文通过构造节点异质性模型,充分考虑节点异质性和节点负载的关系,提出新的Skip Graphs++算法,有效降低系统的维护代价10%～30%,并从理论和仿真两方面进行证明.

线图的补图的Wiener指标

令G是一个边数不小于1的图。我们称图G的线图L(G)的补图为跳图,记作J(G)。图G的Wiener指标是图G中所有点对的距离之和。在本文中,我们确定了图J(G)的Wiener指标,其中图J(G)是连通的。

基于可搜索加密的密态知识图谱存储和检索方案

随着云计算的快速发展,知识图谱数据外包成为一种流行的趋势。医疗、金融等诸多领域中的知识图谱有着隐私敏感特性,然而云服务器并不是完全可信的,为了保护数据在云服务器上的机密性和完整性,需要使用加密等方式来保护知识图谱数据的安全。提出了一种基于可搜索加密的密态知识图谱存储方案,可以有效保护数据的机密性和完整性,并且支持在密态数据上的检索。该方案充分考虑了知识图谱实体及其关系顺序读取的必要性,从而对密态索引设计进行优化,加快检索效率。实验结果显示,密态知识图谱的一跳子图查询平均时间为非密态知识图谱的2.09倍,表明该方案在安全性和查询效率上取得了良好的平衡。

Cycle slip detection approach based on time-relative positioning theory

An efficient cycle slip detection method is proposed for high precision positioning and navigation results with global positioning system （GPS）,which is based on the assumption of a high sampling interval, measurement errors are so small that they can be ignored in the temporal single difference observables. And ambiguities are ordinarily equal to zero,but could be the number of cycles that have ＂slipped＂ if loss-of-lock has occurred.Therefore,cycle slips are estimated as parameters of time-relative positioning observation equations.Because the temporal single difference observables are taken at different epochs and different stations with a single GPS receiver,if time-relative positioning observation equations are linearized as that of conventional relative positioning,the design matrix will be rank defective.To obtain a stable linearization scheme,time-relative positioning observation equations are further analyzed,and the concept of virtual measurement is applied.A sample of data collected on a vehicle test shows that a cycle slip detection approach based on time-relative positioning theory can detect slips at the value of one cycle.The results also indicate if two satellites are so near to each other that they have the same equivalent to satellite-receiver geometry,cycle slip detection will be difficult and may get wrong results.Cycle slips of different satellites also affect detection by satellite-receiver geometry.

Novel Strategy for Numerically Evaluating Dark-Soliton Jitter in Optical Communications

In this paper, a novel strategy for numerically evaluating the dark-solitonjitter in optical communications is proposed. It is further tested to be consistent with the famousthreshold-value-oriented method for rather larger distances. Then our method is used to calculatethe dark-soliton jitter within arbitrary small distances. An excellent agreement is obtained withthe theoretical predictions based on the nonlinear Schrddinger equation. Our method is alsoapplicable to some more complicated systems such as the dissipative-dispersive system.

Comparison of plasma NSE, protein S-100b and EEG changes in traditional arrested-heart procedures and on-pump beating-heart procedures

Objective: To assess the cerebral injury in on-pump beating-heart procedures under mild hypothermia in comparison with traditional on-pump arrested-heart procedures under moderate hypothermia. Methods: Forty patients, 20 with congenital heart disease (CHD) and 20 of rheumatic heart disease (RHD) , were divided into 2 groups: Control group (group A, n =20) including 10 patients suffering from CHD as group Al and the left 10 from RHD as group A2; and experiment group (group B, n =20) which consisting of group B1 (10 with CHD) and group B2 (10 of RHD). The patients in group A underwent traditional arrested-heart procedures, and those in group B were operated on with beating-heart procedures. Arterial blood samples were collected at preoperation (time A) , 20 min after cardiopul-monary bypass (CPB) starting (time B) , 1 h after CPB (time C) and 24 h postoperation (time D) respectively. Plasma contents of neuron-specific enolase (NSE) and protein S-100b were measured with sensitive ELISA. All the patients received echoencephalography (EEG) before and 1 week after operation. Results: The plasma contents of protein S-lOOb were increased very significantly at time B, C and D in comparison with those at time A (P<0.01) , and that of patients in group Al was significantly higher than that in group B at time B (P < 0. 05 ). There was no significant difference at other time points. At time B, the plasma contents of NSE were significantly higher in group A than in group B, and in group Al and Bl than in group A2 and B2. What's more, at time B, the former fell back to their pre-operative levels, but the latter remained still higher levels than the preoperative ones ( P < 0.01). No significant difference was found in the abnormality rates of postoperative EEG between 2 groups. Conclusion: The perioperative plasma contents of NSE and protein S-100b are not significantly higher in group B than in group A. On-pump beating-heart procedures do not make more serious cerebral dysfunction than the traditional arrested-heart procedures.

凭栏可穷千里目——读李寅《清江凭眺图》

当我们展开这幅画的时候，多么希望时光倒流，希望在如画江山中临风而立的那个人就是自己。为什么在今天看古画时还是会这般流连，那分向往。就是因为画里山蒸水浮，如屏若障，峰峦奇峭，烟云明灭。画外社会浮躁，光影变幻，人心不古，乱相弥漫。身处当下，面对强烈的世象反差，甚至常常会有生不逢时的感叹。然而，凝眸览古，视觉不再疲劳；与之相望，仿佛能得到心灵的安顿。

The low_n and low_m r. e. degrees are not elementarily equivalent

Jockusch, Li and Yang showed that the Lown and Low1 r.e. degrees are not elementarily equivalent for n>1. We answer a question they raise by using the results of Nies, Shore and Slaman to show that the Lown and Lowm r.e. degrees are not elementarily equivalent for n > m > 1.