期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
Padé approximations of quantized-vortex solutions of the Gross–Pitaevskii equation
1
作者 weiru chen Shanquan Lan +3 位作者 Xiyi Liu Jiexiong Mo Xiaobao Xu Guqiang Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第8期171-181,共11页
Quantized vortices are important topological excitations in Bose–Einstein condensates. The Gross–Pitaevskii equation is a widely accepted theoretical tool. High accuracy quantized-vortex solutions are desirable in m... Quantized vortices are important topological excitations in Bose–Einstein condensates. The Gross–Pitaevskii equation is a widely accepted theoretical tool. High accuracy quantized-vortex solutions are desirable in many numerical and analytical studies. We successfully derive the Padéapproximate solutions for quantized vortices with winding numbers ω = 1, 2, 3, 4, 5, 6 in the context of the Gross–Pitaevskii equation for a uniform condensate. Compared with the numerical solutions, we find that(1) they approximate the entire solutions quite well from the core to infinity;(2) higher-order Padé approximate solutions have higher accuracy;(3) Padé approximate solutions for larger winding numbers have lower accuracy. The healing lengths of the quantized vortices are calculated and found to increase almost linearly with the winding number. Based on experiments performed with 87Rb cold atoms, the healing lengths of quantized vortices and the number of particles within the healing lengths are calculated, and they may be checked by experiment. Our results show that the Gross–Pitaevskii equation is capable of describing the structure of quantized vortices and physics at length scales smaller than the healing length. 展开更多
关键词 Gross-Pitaevskii equation Padéapproximation quantized-vortex solution
原文传递
基于K-Shape和LSTM两阶段优化的船舶备件深度学习需求预测
2
作者 陈薇如 傅文翰 《运筹与模糊学》 2025年第5期59-67,共9页
船舶备件多为突发性需求,同时具有价值高、缺件损失大等特点,准确的需求预测可以帮助船舶企业优化库存,减少缺货导致的停航损失和紧急采购的高成本。因此,本文提出一种结合K-Shape聚类与两阶段LSTM的船舶备件深度学习预测方法。首先利用... 船舶备件多为突发性需求,同时具有价值高、缺件损失大等特点,准确的需求预测可以帮助船舶企业优化库存,减少缺货导致的停航损失和紧急采购的高成本。因此,本文提出一种结合K-Shape聚类与两阶段LSTM的船舶备件深度学习预测方法。首先利用K-Shape算法对船舶备件产品的历史需求数据进行聚类;其次针对具有间歇性特征的备件构建两阶段LSTM模型,以期达到更好的预测效果;最后,以W公司为案例对所提方法进行验证。结果表明,两阶段LSTM在间歇性类别中预测效果最优,各评价指标优化率均明显优于其他类别,且相较于单阶段LSTM,RMSE、MAE、R2及MASE的优化率分别可达10.99%、15.39%、9.24%及16.10%。因此,所提出的两阶段LSTM方法适用于间歇性备件的需求预测,且预测效果更好。 展开更多
关键词 船舶建造 备件需求预测 长短期记忆网络 K-Shape时间序列聚类
在线阅读 下载PDF
Systematic analysis of artificial intelligence in the era of industry 4.0
3
作者 weiru chen Wu He +2 位作者 Jiayue Shen Xin Tian Xianping Wang 《Journal of Management Analytics》 EI 2023年第1期89-108,共20页
Artificial Intelligence has been playing a profound role in the global economy,social progress,and people’s daily life.With the increasing capabilities and accuracy of AI,the application of AI will have more impacts ... Artificial Intelligence has been playing a profound role in the global economy,social progress,and people’s daily life.With the increasing capabilities and accuracy of AI,the application of AI will have more impacts on manufacturing and service areas in the era of industry 4.0.This study conducts a systematic literature review to study the state-of-the-art on AI in industry 4.0.This paper describes the development of industries and the evolution of AI.This paper also identifies that the development and application of AI will bring not only opportunities but also challenges to industry 4.0.The findings provide a valuable reference for researchers and practitioners through a multi-angle systematic analysis of AI.In the era of industry 4.0,AI system will become an innovative and revolutionary assistance to the whole industry. 展开更多
关键词 Industry 4.0 AI deep learning neural network supervised learning unsupervised learning reinforced learning
原文传递
Fractional-Degree Expectation Dependence
4
作者 Jianping Yang weiru chen Weiwei Zhuang 《Communications in Mathematics and Statistics》 SCIE CSCD 2023年第2期341-368,共28页
We develop a fractional-degree expectation dependence which is the generalization of the first-degree and second-degree expectation dependence.The motivation for introducing such a dependence notion is to conform with... We develop a fractional-degree expectation dependence which is the generalization of the first-degree and second-degree expectation dependence.The motivation for introducing such a dependence notion is to conform with the preferences of decision makers who are mostly risk averse but would be risk seeking at some wealth levels.We investigate some tractable equivalent properties for this new dependence notion,and explore its properties,including the invariance under increasing and concave transformations,and the invariance under convolution.We also extend our results to a combined fractional-degree expectation dependence notion includingε-almost firstdegree expectation dependence.Two applications on portfolio diversification problem and optimal investment in the presence of a background risk illustrate the usefulness of the approaches proposed in the present paper. 展开更多
关键词 Expectation dependence Incomplete risk aversion Confined correlation aversion Optimal investment
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部