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1.
In this paper, we present LinkingPark, an automatic semantic annotation system for tabular data to knowledge graph matching. LinkingPark is designed as a modular framework which can handle Cell-Entity Annotation (CEA), Column-Type Annotation (CTA), and Columns-Property Annotation (CPA) altogether. It is built upon our previous SemTab 2020 system, which won the 2nd prize among 28 different teams after four rounds of evaluations. Moreover, the system is unsupervised, stand-alone, and flexible for multilingual support. Its backend offers an efficient RESTful API for programmatic access, as well as an Excel Add-in for ease of use. Users can interact with LinkingPark in near real-time, further demonstrating its efficiency. 相似文献
2.
Damir Sagdeev Il'giz Gabitov Chingiz Isyanov Vener Khairutdinov Mansur Farakhov Zufar Zaripov Ilmutdin Abdulagatov 《Journal of the American Oil Chemists' Society》2019,96(6):647-662
The densities of oleic acid were measured over the temperature range from (293 to 459) K at atmospheric pressure using a densimeter based on the modified hydrostatic weighing method. The dynamic viscosities of the same oleic acid sample were measured using a capillary viscometer (VPZ-2 m) in the range from (293 to 363) K at atmospheric pressure. The combined expanded uncertainty of the density, atmospheric pressure, viscosity, and temperature measurements at the 95% confidence level with a coverage factor of k = 2 is estimated to be 0.15%, 1.0%, 3.5%, and 15 mK, respectively. The values of uncertainty for density and viscosity include the effects of purity and calibration (total expanded uncertainty). These experimental data were used to develop wide-range correlations for the density and viscosity based on theoretically confirmed Arrhenius–Andrade and Vogel-Tamman-Fulcher (VTF) models. The value of the glass temperature ( T g= 179.78 K.) for the oleic acid was estimated using the VTF parameters derived from the present viscosity measurements. To additionally validate the reliability of the measured density data, the same oleic acid samples were measured using the pycnometric method. The present study showed that the densities measured using the modified hydrostatic weighing densimeter (HWD) agree with the values obtained using the pycnometric method within 0.09% for Sample 1 and 0.25% for Sample 2. 相似文献
3.
《Geotextiles and Geomembranes》2021,49(5):1256-1269
This study investigates the seismic performance of geosynthetic-reinforced modular block retaining walls backfilled with cohesive, fine grained clay-sand soil mixture. Shaking table tests were performed for three ½ scaled (wall height 190 cm) and ¼ scaled model walls to investigate the effects of backfill type, the influence of reinforcement length and reinforcement stiffness effects. The El Centro and Kobe earthquake records of varying amplitudes were used as base acceleration. Displacement of the front wall, accelerations at different locations, strains on the reinforcements, and the visual observations of the facing and the backfill surface were used to evaluate the seismic performance of model walls. The model walls were subjected to rigorous shaking and the walls did not exhibit any stability problems or signs of impending failure. The maximum deformations observed on the models with cohesive backfill was less than half of the deformation of the sand model. The load transfers between the geogrid and cohesive soil was comparable to that of sand and hence the needed reinforcement length was similar as well. As a result; the model walls with cohesive backfills performed within acceptable limits under seismic loading conditions when compared with granular backfilled counterparts. 相似文献
4.
基于粗糙集信息观的决策表属性约简方法 总被引:2,自引:0,他引:2
粗糙集理论是近年来发展起来的一种有效的处理不精确、不确定、含糊信息的数学理论方法,它被广泛应用于相容和不相容决策表的属性约简和核属性计算。利用反例指出目前基于粗糙集信息观[2、6]的决策表属性约简和核属性计算方法的局限性。对决策表的性质作了深入的研究,研究发现文献[2、6]方法的不足原因是:它们没有考虑U/ind(C)中等价类的相客性。给出了基于U/ind(C)中等价类相客性的属性约简定义和核属性定义,并给出了一种新的基于粗糙集信息观的决策表属性约简和核属性计算方法。讨论了该方法同文献[2、6]方法的区别。最后用相同实例验证了该方法的有效性。 相似文献
5.
本文提出了属性相关表这样一种新的概念,定义了相应的运算并研究了它的有关性质及定理,在此基础上提出了用属性相关表求关系模式全部主属性的等级,并给出了用主属性来组合关系模式全部候选关键字的算法,上述算法的时间复杂度均为O(n^2)。 相似文献
6.
本文提供了SN388在三维施工中炮点表的几种设置方法,并进行了相应的对比说明,最后给出了改进炮点表设置的有关设想。 相似文献
7.
因为电子衡器在安装与调试过程中出现的较为特殊的故障,难以找出正确的起因与处理方法,所以介绍了如何保证电子衡器的正常使用和计量准确性的工作体会。 相似文献
8.
本文介绍了一种实用的数据库设计方法,它以实体分析法为理论基础,通过对我们日常使用的表进行聚集和归类,完成数据库的逻辑设计,所设计的数据库满足BNOF范式。同时该方法可操作性较强,本文还介绍了自行设计的ERCM数据库辅助设计工具。 相似文献
9.
R. Masui 《International Journal of Thermophysics》2002,23(4):921-935
The development of a magnetic suspension densimeter that has been built for measurement of the density of compressed liquid at pressures up to 30 MPa in the temperature range 20 to 150°C is described. The densimeter was first built by the author and his coworkers at NIST. We describe here further improvements made on a second system built at NMIJ based on the same principle. The densimeter uses a small coil suspended from an electronic balance. Within the coil is placed a sample cell in which the pressurized sample and a buoy, which is a permanent magnet, are enclosed. For measurement of density, balance readings are recorded (1) with the buoy at rest and (2) with the buoy in magnetic suspension. The measurement procedure is basically a hydrostatic weighing, which is simpler than those of conventional magnetic densimetry. As an example, measurements of toluene density performed as part of an inter-laboratory comparison are presented. The data agreed with reliable literature values to within a few hundredths of a per cent. 相似文献
10.