Multi-level Spatio-temporal Matching Network for Multi-turn Response Selection in Retrieval-based Dialogue Systems

Author(s):  
Mei Ma ◽  
Jianji Wang ◽  
Xuguang Lan ◽  
Nanning Zheng
2019 ◽  
Vol 8 (11) ◽  
pp. 512 ◽  
Author(s):  
Li ◽  
Wu ◽  
Wu ◽  
Zhao

Spatio-temporal indexing is a key technique in spatio-temporal data storage and management. Indexing methods based on spatial filling curves are popular in research on the spatio-temporal indexing of vector data in the Not Relational (NoSQL) database. However, the existing methods mostly focus on spatial indexing, which makes it difficult to balance the efficiencies of time and space queries. In addition, for non-point elements (line and polygon elements), it remains difficult to determine the optimal index level. To address these issues, this paper proposes an adaptive construction method of hierarchical spatio-temporal index for vector data. Firstly, a joint spatio-temporal information coding based on the combination of the partition and sort key strategies is presented. Secondly, the multilevel expression structure of spatio-temporal elements consisting of point and non-point elements in the joint coding is given. Finally, an adaptive multi-level index tree is proposed to realize the spatio-temporal index (Multi-level Sphere 3, MLS3) based on the spatio-temporal characteristics of geographical entities. Comparison with the XZ3 index algorithm proposed by GeoMesa proved that the MLS3 indexing method not only reasonably expresses the spatio-temporal features of non-point elements and determines their optimal index level, but also avoids storage hotspots while achieving spatio-temporal retrieval with high efficiency.


2020 ◽  
Vol 34 (07) ◽  
pp. 13066-13073 ◽  
Author(s):  
Tianfei Zhou ◽  
Shunzhou Wang ◽  
Yi Zhou ◽  
Yazhou Yao ◽  
Jianwu Li ◽  
...  

In this paper, we present a novel Motion-Attentive Transition Network (MATNet) for zero-shot video object segmentation, which provides a new way of leveraging motion information to reinforce spatio-temporal object representation. An asymmetric attention block, called Motion-Attentive Transition (MAT), is designed within a two-stream encoder, which transforms appearance features into motion-attentive representations at each convolutional stage. In this way, the encoder becomes deeply interleaved, allowing for closely hierarchical interactions between object motion and appearance. This is superior to the typical two-stream architecture, which treats motion and appearance separately in each stream and often suffers from overfitting to appearance information. Additionally, a bridge network is proposed to obtain a compact, discriminative and scale-sensitive representation for multi-level encoder features, which is further fed into a decoder to achieve segmentation results. Extensive experiments on three challenging public benchmarks (i.e., DAVIS-16, FBMS and Youtube-Objects) show that our model achieves compelling performance against the state-of-the-arts. Code is available at: https://github.com/tfzhou/MATNet.


2019 ◽  
Author(s):  
Jiazhan Feng ◽  
Chongyang Tao ◽  
Wei Wu ◽  
Yansong Feng ◽  
Dongyan Zhao ◽  
...  

2019 ◽  
Author(s):  
Matthew P J Ashby

Objectives: Research evidence on schools as a factor in the distribution of neighborhood violence has produced varying and at-times directly contradictory results. Drawing conclusions from existing research is also complicated by data limitations and methodological differences. The present study sought to further research in this area using a novel open-data source.Methods: Police-recorded assault and personal robbery data from nine large US cities were used to test four hypotheses (derived from the routine activities approach) on spatio-temporal patterns of violence around schools. Multi-level Markov Chain Monte Carlo models were used to reflect the clustered structure of the data.Results: The presence of a public secondary (middle or high) school in a census block group was associated with higher daytime assault and robbery counts on weekdays when schools were in session but not on non-school weekdays, and the effect was larger for larger schools. No such relationships were found for elementary schools. However, there were variations between cities, in that there was no effect in one city and the effect sizes in other cities varied substantially.Conclusions: The results were consistent with the routine activites approach, suggesting a role for middle and high schools in the distribution of neighbourhood violence. The differences between cities suggest that studying multiple cities is important in the investigation of crime and place, and that open data may provide a mechanism for overcoming the data-access difficulties that have previously limited multi-city studies of spatio-temporal variations in crime.


2020 ◽  
Vol 63 ◽  
pp. 101080
Author(s):  
Basma El Amel Boussaha ◽  
Nicolas Hernandez ◽  
Christine Jacquin ◽  
Emmanuel Morin

Sociology ◽  
2018 ◽  
Vol 53 (2) ◽  
pp. 246-263 ◽  
Author(s):  
Umut Erel ◽  
Louise Ryan

This article explores how migrants utilize and access different forms of capital. Using a Bourdieusian approach to capital, we focus on how migrants’ temporal and spatial journeys are shaped by and in turn shape their opportunities to mobilize resources and convert them into capitals. These processes depend on migrants’ social positioning, including their gender, class, ethnic and national positioning, as well as citizenship status, and how this is articulated in relation to different fields in different spatial and temporal contexts. Drawing upon our combined corpus of data on migration to the UK, and a lesser extent Germany, with third country nationals and EU citizens and new data collected since the Brexit referendum, we examine these issues through biographical approaches to migrant women’s life stories. In so doing, we build theory on capital accumulation as dynamic, multi-level and spatio-temporally contingent.


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