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1.
Wei Xu Ziping Huang Weimin Han Wenbin Chen Cheng Wang 《Computers & Mathematics with Applications》2019,77(10):2596-2607
In this paper numerical approximation of history-dependent hemivariational inequalities with constraint is considered, and corresponding Céa’s type inequality is derived for error estimate. For a viscoelastic contact problem with normal penetration, an optimal order error estimate is obtained for the linear element method. A numerical experiment for the contact problem is reported which provides numerical evidence of the convergence order predicted by the theoretical analysis. 相似文献
2.
基于深度学习的人体姿态估计方法旨在通过构建合适的神经网络,直接从二维的图像特征中回归出人体姿态信息。主要按照2D人体姿态估计到3D人体姿态估计的顺序,并从单人检测与多人检测、稀疏的关节点检测与密集的模型构建等方面,对近年来基于深度学习的人体姿态估计方法进行系统介绍,从而初步了解如何通过深度学习的方法得到人体姿态的各个要素,包括肢体部件的相对朝向和比例尺度、骨骼关节点的位置坐标和连接关系,甚至更为复杂的人体蒙皮模型信息。最后,对当前研究面临的挑战以及未来的热点动向进行概述,清晰地呈现出该领域的发展脉络。 相似文献
3.
风电机组齿轮箱的故障频率和维修成本较高,有必要对其运行状态进行实时监测。非线性状态估计(NSET)算法有着对记忆矩阵依赖大、无法有效利用数据资源改善精度、实时性差等不足。为此,提出一种基于模糊软聚类和集成NSET的状态监测方法:使用模糊软聚类将历史数据分为边界有重叠的不同类别,实现工况的软划分并构造多个不同工况的NSET模型作为个体学习器;以参数回归方法作为结合器,可在不影响实时性的同时,使用大量数据训练参数以改善精度。用某2 MW风电机组的齿轮箱故障数据进行验证,结果表明,相比常规方法,提出方法的精度和实时性均更优;通过预测残差均值和基于残差构造的健康指数,能够灵敏、准确的反映齿轮箱的早期故障及其发展趋势。 相似文献
4.
Nuclear power plant Safety analysis using coupled 3D neutron kinetics/thermal-hydraulic codes technique is increasingly used nowadays. Actually, the use of this technique allows getting less conservatism and more realistic simulations of the physical phenomena. The challenge today is oriented toward the application of this technique to the operating conditions of nuclear research reactors. In the current study, a three-Dimensional Neutron Kinetics and best estimate Thermal-Hydraulic model based upon the coupled PARCS/RELAP5 codes has been developed and applied for a heavy water research reactor. The objective is to perform safety analysis related to design accidents of this reactor types. In the current study two positive reactivity insertion transients are considered, SCRAM protected and self-limiting power excursion cases. The results of the steady state calculations were compared with results obtained from conventional diffusion codes, while transient calculations were assessed using the point kinetic model of the RELAP5 code. Through this study, the applicability and the suitability of using the coupled code technique with respect to the classical models are emphasized and discussed. 相似文献
5.
This paper addresses reliable and efficient calculation of the mode of a multivariate sample, which is a classical fusion function. In particular, we focus on the inputs given on the unit simplex, when aggregating elements of Atanassov intuitionistic fuzzy sets, interval-valued fuzzy sets and their extensions, as well as compositional data. We outline the use of a specially designed 2-additive fuzzy measures and the Choquet integral for the purposes of reducing computational complexity in higher dimensions. We present computational analysis and benchmark four different methods of density-based mode estimation. 相似文献
6.
In general, preliminary or primary cost estimates are used to select contractors from among bidders in Japan. The primary cost estimate must be accurate, otherwise the contractor selected from the bidding process will lose profit. A general contractor in the world does not have a super-skilled engineer who can achieve the accurate primary cost estimates. The conventional primary estimate has a high error range and low reliability. An automated system converting detailed estimates to primary estimates has been highly demanded in the world. This paper presents a prototype AI converter that can accurately and automatically convert detailed cost estimates into primary estimates. Converting detailed cost estimates to primary estimates lies in a regression problem. This paper proposes a feature-elimination based data augmentation method for regression problems. The empirical experiment shows that the proposed data augmentation method is quite effective with an Extra-Trees ensemble method. The proposed method was empirically examined by using Colorado Department of Transportation (CDOT) dataset for accurately predicting constructions costs with the Extra-Trees algorithm and random forest algorithm respectively. The CDOT dataset is one and only one of the largest datasets available in public for constructions costs quotation/estimation of roads, bridges and buildings. 相似文献
7.
Radial size estimation using radar high-resolution range profiles(HRRPs) and heading angle estimation are the main means for ship classification.The classification ability is closely related to the range resolution of the radar,precision of radial size estimation,and prior distribution of ship lengths in different offshore areas.We collected the AIS information on about 30 000 ships and their lengths in the four offshore areas of China in the ship information net of China.By fitting the data of ship lengths in each offshore area,it is found that the Weibull distributions provide good-of-fitness to the ship lengths and the parameters in individual area are rather different.Based on the prior distributions of ship lengths,we derived the quantitative relationship between the correct classification probability of big-moderate-small ships and the estimate error of ship radial size.The results indicate that the condition for the big-moderate-small correct classification probability in the offshore areas of China to be up to 90% is that the estimate errors of the ship radial size estimates falls into the interval(-12.67 m,9.41 m) when the heading angle of the ship is between ±75 degrees. 相似文献
8.
提高概预算编制质量合理确定工程造价 总被引:3,自引:2,他引:3
为了合理地确定工程造价,从严格取定概预算编制依据,广泛搜集基础资料,为概预算编制作准备,正确套用定额等方面,提出了提高概预算编制质量,合理确定工程造价的方法。 相似文献
9.
地区间货物运输量预测方法谱系 总被引:3,自引:0,他引:3
本文整理了近些年地区间(城市间)货物运输量预测方法的研究。论文分析了和旅客运输相比,地区间货物运输的特点,提出了货物运输需求量的预测在理论和方法上和客流需求量的预测有所不同的依据。将以往的地区间货运量预测模型按不同阶段做了分类整理。其次,根据物流的行为者将地区间货运量预测模型分为计量经济学模型、空间相互作用模型及网络模型等类型。较为详尽地分析了各类预测模型的特点。并结合我国物流业的发展现状,对货物运输量预测方法研究的发展方向进行了展望。 相似文献
10.
介绍了现场签证的工作范围和存在的问题,说明了现场签证在工程结算中的重要作用,并对如何成功索赔提出了看法,提出施工企业只有做好现场签证工作,做到成功索赔,才能获得更大的利润。 相似文献