A two-stage adaptive multi-fidelity surrogate model-assisted multi-objective genetic algorithm for computationally expensive problems

Surrogate model-assisted multi-objective genetic algorithms (MOGA) show great potential in solving engineering design problems since they can save computational cost by reducing the calls of expensive simulations. In this paper, a two-stage adaptive multi-fidelity surrogate (MFS) model-assisted MOGA (AMFS-MOGA) is developed to further relieve their computational burden. In the warm-up stage, a preliminary Pareto frontier is obtained relying only on the data from the low-fidelity (LF) model. In the second stage, an initial MFS model is constructed based on the data from both LF and high-fidelity (HF) models at the samples, which are selected from the preliminary Pareto set according to the crowding distance in the objective space. Then the fitness values of individuals are evaluated using the MFS model, which is adaptively updated according to two developed strategies, an individual-based updating strategy and a generation-based updating strategy. The former considers the prediction uncertainty from the MFS model, while the latter takes the discrete degree of the population into consideration. The effectiveness and merits of the proposed AMFS-MOGA approach are illustrated using three benchmark tests and the design optimization of a stiffened cylindrical shell. The comparisons between the proposed AMFS-MOGA approach and some existing approaches considering the quality of the obtained Pareto frontiers and computational efficiency are made. The results show that the proposed AMFS-MOGA method can obtain Pareto frontiers comparable to that obtained by the MOGA with HF model, while significantly reducing the number of evaluations of the expensive HF model.

     

GRU-based capsule network with an improved loss for personnel performance prediction

Applied Intelligence - Personnel performance is a key factor to maintain core competitive advantages. Thus, predicting personnel future performance is a significant research domain in human...     

浅谈云计算与物联网的融合发展

该文从云计算与物联网相融合的角度了介绍了云计算和物联网当前的状况,分析了两者协同发展的可行性。目前物联网的发展已经提升到了国家战略的高度,引起了各界特别是IT界的高度关注。但是物联网的发展离不开它的支持平台,特别是云计算的帮助。二者的发展是相互促进,相互渗透的。云计算作为一种计算模型已经为物联网的前身-无线传感网提供了大量的技术支持,使物联网的出现及发展成为可能。该文分析了云计算和物联网的关系、融合的模式,并指出二者的发展前景和面临的挑战。     

在CodeWarrior编译环境下运行μC／OS—Ⅲ

μC／OS-Ⅱ是面向8／16位及低端32位单片机应用的RTOS,而新近推出的μC／OS-Ⅲ则面向高性能32位单片机,如ARMCortex等。以Cortex—M4为内核的Kinetis系列单片机,不仅用于全国大学生飞思卡尔杯智能车竞赛,也用于诸多大学的嵌入式系统教学,官方提供的开发环境是CodeWarrior。本文介绍如何利用CodeWarrior开发环境,将μC／OS-Ⅲ在Kinetis单片机上运行起来,以便将μC／OS-Ⅲ引入教学、科研与应用。     

卫星宽带网络系统的研究与分析

本文主要介绍了卫星宽带网络系统的基本原理、技术特点、发展现状和应用趋势,通过研究和分析,证明了卫星宽带网络在信息通信领域具有广阔的应用前景。     

Birman–Wenzl–Murakami algebra, topological parameter and Berry phase

In this paper, a 3?×?3-matrix representation of Birman?CWenzl?CMurakami (BWM) algebra has been presented. Based on which, unitary matrices A(??, ?? ₁, ?? ₂) and B(??, ?? ₁, ?? ₂) are generated via Yang?CBaxterization approach. A Hamiltonian is constructed from the unitary B(??, ??) matrix. Then we study Berry phase of the Yang?CBaxter system, and obtain the relationship between topological parameter and Berry phase.     

A New Transmit Beamforming Method for Multi-User Communication in Dual-Function Radar-Communication

This paper develops a new transmit beamforming for an integrated mechanical and electrical scanning dual-function radar-communication(DFRC) system. Differing from the related some works using beampattern sidelobe level to communication, we exploit the fact that transmit beamforming weight vector u k in direction θ and weight vector u *k in direction-θ can achieve the same spatial power distribution, and formulate a new transmit beamforming vector design problem accounting for some extra sidelobe level constraints. By doing so, the number of the transmit beamforming weight vectors and the computing demand in the multi-user communication(MUC) scenario can be reduced. Finally, the numerical examples are designed to verify the effectiveness of the proposed design strategy in comparison with the existing method.     

打造学生真心喜爱的思政课

从思政课缺乏对学生吸引力的现状入手,分析当前思政课教学面临的新形势,进而提出从提高教学的内在吸引力、发挥思政课的实践性和实效性以及讲好思政课3个方面打造学生喜爱的思政课;对如何增强思政课的思想性、理论性,如何突出思政课的实践性和实效性,如何发挥教师的积极性、主动性、创造性,提出相应建议.     

Zr－1Nb合金吸氢性能研究

研究了１３种不同加工热处理制度的Ｚｒ－１Ｎｂ合金在堆外高压釜内３６０℃、１９ＭＰａ水中的吸氢性能，对其影响因素和吸氢机理进行了分析，并讨论了吸氢动力学，建立了吸氢动力学方程，计算了吸氢动力学参数。     

铝质材料的摩擦学表面改性

铝质材料阳极氧化膜系均匀、规则的微观多孔质结构，利用物理、化学或电化学的方法在其中沉积或原位合成润滑性物质，在保持阳极氧化膜质硬、耐磨特性的基础上，使其具有一定的白润滑性，是近十多年来铝质材料表面改性研究的热点领域之一，本文对该研究的基本原理和国内外发展概况进行了概述，并重点介绍了我们在这一方面研究中的一些最新进展和结果，分别介绍了三种新型体系的自润滑改性阳极氧化铝材料．