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Journal of Systems Science and Systems Engineering 2016年第2期25卷 159-176页

作者： Gongzhuang peng huachao Mao Hongwei Wang Heming Zhang National CIMSEngineeringResearch Center Tsinghua University Beijing 100084 China School of Engineering University of Portsmouth Anglesea Read Portsmouth PO1 3D J UK

Modem product development becomes increasingly collaborative and integrated, which raises the need for effectively and efficiently sharing and re-using design knowledge in a distributed and collaborative environment. To address this need, a framework is developed in this research to support design knowledge representation, retrieval, reasoning and fusion, which takes account of structural, functional and behavioral data, various design attributes and knowledge reasoning cases. Specifically, a multi-level knowledge representation based on the Base Object Model （BOM） is proposed to enable knowledge sharing using Web services technologies. On this basis, a multi-level knowledge reuse method is developed to support the retrieval, matching and assembly of knowledge records. Due to the tree structure of BOM, both depth-first and breadth-first searching strategies are employed in the retrieval algorithm while a novel measure is proposed to evaluate similarity. Moreover, a method based on the D-S evidence theory is developed to enable knowledge fusion and thus support effective decision-making. The framework has been implemented and integrated into an HLA-based simulation platform on which the development of a missile simulation example is conducted. It is demonstrated in the case study that the proposed framework and methods are useful and effective for design knowledge representation and reuse.

关键词： Complex product development multi-level knowledge reuse knowledge fusion Base Object Model D-S evidence theory

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港口码头固定式气幕围油栏研究及应用设计

机械工程师 2019年第1期 88-91,95页

作者：彭华超卢金树陈阳吕童童邵泽远浙江海洋大学港航与交通运输工程学院浙江舟山316022

港口码头油船装卸易发生意外事故,为防止油品扩散,需要配备围油栏。为解决固体围油栏布放回收麻烦、费时费力、不能及时有效地围住溢油的问题,以流体力学相似准则并按缩尺比例1:90开展海试试验,验证了实际海况下气幕围油栏围油的可行性... 详细信息

港口码头油船装卸易发生意外事故,为防止油品扩散,需要配备围油栏。为解决固体围油栏布放回收麻烦、费时费力、不能及时有效地围住溢油的问题,以流体力学相似准则并按缩尺比例1:90开展海试试验,验证了实际海况下气幕围油栏围油的可行性。以提高气幕围油栏应用可行性为目标,结合试验数据及油轮码头地理特征,在船舶及海洋工程规范的基础上,设计一种可在港口码头长期固定连接、快速实现布放和回收的固定式气幕围油栏应用系统。研究表明,固定式气幕围油栏操作简单,可及时围住溢油,对保护海洋环境有直接促进作用。

关键词：气幕围油栏固定式围油性能海洋环保

Hybrid vector beams with non-uniform orbital angular momentum density induced by designed azimuthal polarization gradient

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Chinese Physics B 2020年第9期29卷 129-135页

作者： Lei Han Shuxia Qi Sheng Liu peng Li huachao Cheng Jianlin Zhao MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi'an 710129China

Based on angular amplitude modulation of orthogonal base vectors in common-path interference method, we propose an interesting type of hybrid vector beams with unprecedented azimuthal polarization gradient and demonstrate in experiment. Geometrically, the configured azimuthal polarization gradient is indicated by intriguing mapping tracks of angular polarization states on Poincaré sphere, more than just conventional circles for previously reported vector beams. Moreover, via tailoring relevant parameters, more special polarization mapping tracks can be handily achieved. More noteworthily, the designed azimuthal polarization gradients are found to be able to induce azimuthally non-uniform orbital angular momentum density, while generally uniform for circle-track cases, immersing in homogenous intensity background whatever base states are. These peculiar features may open alternative routes for new optical effects and applications.

关键词： hybrid vector beam polarization gradient polarization mapping track orbital angular momentum density

Modulation of orbital angular momentum on the propagation dynamics of light fields

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Frontiers of Optoelectronics 2019年第1期12卷 69-87页

作者： peng LI Sheng LIU Yi ZHANG Lei HAN Dongjing WU huachao CHENG Shuxia QI Xuyue GUO Jianlin ZHAO MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of ScienceNorthwestern Polytechnical UniversityXi’an 710072China

Optical vortices carrying orbital angular momentum(OAM)have attracted extensive attention in recent decades because of their interesting applications in optical trapping,optical machining,optical communication,quantum information,and optical *** effects induced by OAMs,such as angular momentum conversion,spin Hall effect of light(SHEL),and spin– orbital interaction,have also gained increasing *** this article,we provide an overview of the modulations of OAMs on the propagation dynamics of scalar and vector fields in free ***,we introduce the evolution of canonical and noncanonical optical vortices and analyze the modulations by means of local spatial ***,we review the Pancharatnam–Berry(PB)phases arising from spin–orbital interaction and reveal the control of beam evolution referring to novel behavior such as spindependent splitting and polarization singularity ***,we discuss the propagation and focusing properties of azimuthally broken vector vortex beams.

关键词： orbital angular momentum polarization spin angular momentum Pancharatnam-Berry (PB) phase angular diffraction

Knowledge-enhanced semantic communication system with OFDM transmissions

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Science China(Information Sciences) 2023年第7期66卷 266-282页

作者： Xiaodong XU huachao XIONG Yining WANG Yue CHE Shujun HAN Bizhu WANG Ping ZHANG State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Broadband Communication Peng Cheng Laboratory

As a promising technology to enable effective multi-modal transmission over wireless channels,semantic communication has attracted a lot of attention from academics and industries. Different from Shannon’s information theory, based on common background knowledge provided by the knowledge base, the goal of semantic communication is transmitting intended useful information from the transmitter and recovered by the receiver at the semantic level. However, the existing studies on semantic communication rarely emphasize the essence and the usage of the knowledge base. In this paper, we propose a knowledge-enhanced semantic communication(KESC) system, where the knowledge base is cloud-edge-device collaborative cached. To solve the problem that float-type symbols are difficult to transmit directly through a radio frequency(RF)system, we adopt orthogonal frequency division multiplexing(OFDM) to transmit semantic vectors directly without some traditional signal processing techniques in semantic information transmission, and the semantic pilot is designed to assist semantic reception. Furthermore, we formulate a multi-encoder transformer based neural network model for the KESC system to support text transmission(KESC-T), where the decoder is implemented with a knowledge graph to enhance the performance of semantic decoding. Besides, we define knowledge-enhanced efficiency(KEE) to measure the gain in semantic recovery accuracy brought by per unit of knowledge. Simulation results demonstrate that the recovery accuracy of our proposed KESC outperforms the compared scheme, especially in low signal-to-noise ratio(SNR) or resource-constrained scenarios.

关键词： semantic communication knowledge graph OFDM transformer deep learning

基于FFD的翼身融合水下滑翔机外形优化设计

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西北工业大学学报 2020年第3期38卷 459-464页

作者：李靖璐王鹏陈旭董华超西北工业大学航海学院陕西西安710002

水下滑翔机发展至今大体上可以分成2个大类:常规布局外形水下滑翔机与非常规布局水下滑翔机。翼身融合水下滑翔机作为一种非常规布局水下滑翔机,因其独特的流体外形布局,具有更好的流体动力特性。但设计出具有优秀水动力性能的翼身融合... 详细信息

水下滑翔机发展至今大体上可以分成2个大类:常规布局外形水下滑翔机与非常规布局水下滑翔机。翼身融合水下滑翔机作为一种非常规布局水下滑翔机,因其独特的流体外形布局,具有更好的流体动力特性。但设计出具有优秀水动力性能的翼身融合水下滑翔机外形较为困难,因此开展翼身融合水下滑翔机外形优化设计研究工作具有十分重要的意义。开展基于自由变形(FFD)的翼身融合水下滑翔机外形优化设计研究,以FFD参数化方法为核心,与CFD求解器、优化算法、网格变形方法相耦合,组成了完整的自动外形优化设计框架,并用该框架开展了翼身融合水下滑翔机外形优化设计工作。以翼身融合水下滑翔机下沉和上浮一个工作周期的平均阻力系数为目标函数,在考虑体积约束的条件下开展外形优化设计,优化结果表明翼身融合水下滑翔机的滑翔性能得到了明显提升。

关键词：海洋工程翼身融合水下滑翔机自由变形外形优化设计框架

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两级系统多学科可靠性设计合成优化方法

西北工业大学学报 2012年第6期30卷 808-813页

作者：张代雨宋保维王鹏董华超西北工业大学航海学院陕西西安710072

针对大规模的不确定性多学科系统,提出了一种基于BLISS方法的两级系统多学科可靠性设计合成优化方法——RBMDOSB。该方法采用了SORA方法的框架,将可靠性分析和多学科设计优化分离开来,分为可靠性分析和确定性多学科设计优化两个问题顺... 详细信息

针对大规模的不确定性多学科系统,提出了一种基于BLISS方法的两级系统多学科可靠性设计合成优化方法——RBMDOSB。该方法采用了SORA方法的框架,将可靠性分析和多学科设计优化分离开来,分为可靠性分析和确定性多学科设计优化两个问题顺序执行,其中,具体使用基于多学科模型的性能评估法进行可靠性分析,应用BLISS方法进行确定性多学科设计优化问题求解,并添加与耦合变量相关的移动量来对多学科设计优化问题的约束进行修正。最后通过具体算例验证了RBM-DOSB方法的可行性和有效性。

关键词：多学科设计优化可靠性设计顺序优化和可靠性评估方法两级系统集成一体化

翼身融合水下滑翔机舱体−骨架耦合结构的离散优化设计

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中国舰船研究 2021年第4期16卷 70-78页

作者：董华超王鹏张益进西北工业大学航海学院陕西西安710072

[目的]运用基于数据驱动的离散优化思路,对翼身融合水下滑翔机舱体−骨架耦合结构进行优化设计。[方法]首先,采用一种Kriging辅助的离散全局优化(KDGO)算法解决计算代价昂贵的黑箱问题,该算法采用一种新颖的加点策略来捕获性能较好的离... 详细信息

[目的]运用基于数据驱动的离散优化思路,对翼身融合水下滑翔机舱体−骨架耦合结构进行优化设计。[方法]首先,采用一种Kriging辅助的离散全局优化(KDGO)算法解决计算代价昂贵的黑箱问题,该算法采用一种新颖的加点策略来捕获性能较好的离散样本点,并在该加点策略中引入多起点数据挖掘方法,主要包含多起点优化、投影、采样和选择4个阶段。其次,建立骨架−舱体耦合结构的参数化模型,并对耦合结构进行吊放变形和深水受压工况的有限元分析。接着,以浮−重比为目标,把骨架结构、舱体结构的强度与稳定性指标作为约束,同时考虑外形和舱体之间的干涉以及骨架和舱体的耦合关系,建立整体耦合结构的离散优化数学模型。最后,将离散优化算法与耦合结构仿真相结合,搭建整体优化框架,同时采用KDGO算法进行200次函数评估,并对实验设计(DOE)采样阶段最优可行点和优化后全局最优点进行对比。[结果]结果显示,全局最优点所对应耦合结构的浮−重比提升了近40%,结果令人满意。[结论]所做研究可为翼身融合水下滑翔机舱体−骨架耦合结构的设计提供参考。

关键词： Kriging模型数据挖掘结构设计结构优化参数化建模有限元分析

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基于模糊决策的快速星图识别

系统工程与电子技术 2022年第5期44卷 1447-1453页

作者：王华超刘静程昊文彭喜衍中国科学院国家天文台北京100101 中国科学院大学天文与空间科学学院北京100049

空间碎片问题日益严重,需要对其进行常态化监测。光学观测作为重要的监测手段,需要依靠快速的光学图像处理技术,采用天文定位方法得到空间碎片的赤经赤纬测量信息。星图识别是天文定位的关键步骤,直接影响着图像处理的速度和结果精度。... 详细信息

空间碎片问题日益严重,需要对其进行常态化监测。光学观测作为重要的监测手段,需要依靠快速的光学图像处理技术,采用天文定位方法得到空间碎片的赤经赤纬测量信息。星图识别是天文定位的关键步骤,直接影响着图像处理的速度和结果精度。本文提出了一种改进的基于模糊决策的快速星图识别方法,在保持快速处理的情况下提高了星表匹配的准确性。利用新疆南山站25 cm望远镜的图像对该方法进行了测试,取得了良好的效果,证明了算法的有效性和稳定性。

关键词：空间碎片天文定位星图识别模糊决策

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