—Precision mapping of landslide inventory is crucial for hazard mitigation. Most landslides generally co-exist with other confusing geological features, and the presence of such areas can only be inferred unambiguous...
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The railtransit Codes contain a large number of schemaless data and text, which are difficult to extract and process. Knowledge Graph can handle large-scale schemaless data, thus it is used to effectively store and m...
The railtransit Codes contain a large number of schemaless data and text, which are difficult to extract and process. Knowledge Graph can handle large-scale schemaless data, thus it is used to effectively store and manipulate relevant information of railtransit Codes. As an essential component, Chinese word segmentation is a difficult problem for building the Knowledge Graph of railtransit Codes. In this paper, we propose a bi-directional maximum matching algorithm and some rules based Chinese word segmentation method, for design Codes of railtransit. In the proposed method, the item information, attribute values and Code names are first segmented by preprocessing. Then, the bidirectional matching algorithm with double dictionary is used to generate the preliminary results. Finally, the preliminary results are further optimized with rules to generate the final results. With testing some design Codes, the experimental results show that the proposed method can improve the accuracy and efficiency of Chinese word segmentation in this field, and it can deal with the update of noun entity library.
Optimizing railway alignments in mountainous regions is known as a very complex and time-consuming engineering work. In this paper, we propose a three dimensional distance transform algorithm to solve this problem and...
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This paper presents a multi-objective optimization method for railway alignment design. An optimization model which considers the economic, environmental, and security effect of the alignment is established. A hybrid ...
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Road curvature and lane number information (hereinafter to be referred as road information) play an important and necessary role in transportation research. In order to avoid the drawbacks, i.e., high cost and poor ti...
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Road curvature and lane number information (hereinafter to be referred as road information) play an important and necessary role in transportation research. In order to avoid the drawbacks, i.e., high cost and poor time effectiveness, of traditional ways existing to obtain the road information, it has become a hot topic to mine road information through GPS data. In this paper, we propose a novel approach for mining road information from low precision GPS data, which including: a) Analyze and test the distribution of real world GPS data; b) Propose the weighted approximation least squares method (WALSM) to mine the curvature information of the road so as to establish the optimal center line of the road; c) Establish the GPS Data Distribution Variance - Road Width Discrete Model (DV-RWDM) so as to get the road lane number information. We demonstrate our approach using real world low precision GPS data and the results show that we can mine the road information with high accuracy. This provide us a lower cost and high timeliness guideline for the processing and application of low precision GPS data.
The rheologicalbehaviors of fresh cement paste with polycarboxylate superplasticizer were systematically *** including superplasticizer to cement ratio（Sp/C）,water to cement ratio（w/c）,temperature,and time were **...
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The rheologicalbehaviors of fresh cement paste with polycarboxylate superplasticizer were systematically *** including superplasticizer to cement ratio（Sp/C）,water to cement ratio（w/c）,temperature,and time were *** cement pastes with Sp/Cs in the range of 0 to 2.0% and varied W/Cs from 0.25 to 0.5 were prepared and tested at 0,20 and 40 °C,*** and rheologicaltests on cement pastes were conducted to characterize the development of the rheologicalbehavior of fresh cement pastes over *** exprimentalresults indicate that the initialflowability and flowability retention over shelf time increase with the growth in superplasticizer dosage due to the plasticizing effect and retardation effect of *** temperature usually leads to a sharper drop in initialflowability and flowability ***,for the cement paste with high Sp/C or w/c,the flowability is slightly affected by *** stress and plastic viscosity show similar variation trends to the flowability under the abovementioned influentialfactors at low Sp/*** the case of high Sp/C,yield stress and plastic viscosity start to decline over shelf time and the decreasing rate descends at elevated ***,two equations to roughly predict yield stress and plastic viscosity of the fresh cement pastes incorporating Sp/C,w/c,temperature and time are developed on the basis of the existing models,in which experimentalconstants can be extracted from a database created by the rheologicaltest results.
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