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Color projector light intensity adaptive high dynamic range 3D measurement method
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作者 HUANG Hao-zhen NIU Bin +2 位作者 CHENG Shen QU Xing-hua ZHANG Fu-min 《中国光学(中英文)》 北大核心 2025年第5期1219-1229,共11页
The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,re... The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,resulting in point cloud loss or reduced accuracy.To address this issue,unlike the pixel modulation method of projectors,we utilize the characteristics of color projectors where the intensity of the three-channel LED can be controlled independently.We propose a method for separating the projector's three-channel light intensity,combined with a color camera,to achieve single exposure and multi-intensity image acquisition.Further,the crosstalk coefficient is applied to predict the three-channel reflectance of the measured object.By integrating clustering and channel mapping,we establish a pixel-level mapping model between the projector's three-channel current and the camera's three-channel image intensity,which realizes the optimal projection current prediction and the high dynamic range(HDR)image acquisition.The proposed method allows for high-precision three-dimensional(3D)data acquisition of HDR scenes with a single exposure.The effectiveness of this method has been validated through experiments with standard planes and standard steps,showing a significant reduction in mean absolute error(44.6%)compared to existing singleexposure HDR methods.Additionally,the number of images required for acquisition is significantly reduced(by 70.8%)compared to multi-exposure fusion methods.This proposed method has great potential in various FPP-related fields. 展开更多
关键词 fringe projection profilometry crosstalk coefficient optimal projection currents high dynamic range
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微项目化学习在人教版初中英语新教材中的实施路径——以Project板块为例 被引量:3
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作者 吕勇民 《中小学英语教学与研究》 北大核心 2025年第1期72-76,共5页
2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习... 2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习的实施路径,即学生在真实情境中发现问题,通过小组合作分解问题,在探索实践中解决问题,接着相互交流分享心得并评价作品,进而对作品升级迭代,再自评参与表现,最终实现素养发展。希望能以此促进课堂教学方式转变,提升教学效能。 展开更多
关键词 初中英语 新教材 project板块 微项目化学习
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Current status and diversity of fish resources in the Pinglu Canal Century Project 被引量:1
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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Knowledge graph construction and complementation for research projects 被引量:1
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作者 LI Tongxin LIN Mu +2 位作者 WANG Weiping LI Xiaobo WANG Tao 《Journal of Systems Engineering and Electronics》 2025年第3期725-735,共11页
Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often comple... Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often complex and inadequate,making it challenging for researchers to conduct in-depth data mining to improve policies or management.To address this problem,this paper adopts a top-down approach to construct a knowledge graph(KG)for research projects.Firstly,we construct an integrated ontology by referring to the metamodel of various architectures,which is called the meta-model integration conceptual reference model.Subsequently,we use the dependency parsing method to extract knowledge from unstructured textual data and use the entity alignment method based on weakly supervised learning to classify the extracted entities,completing the construction of the KG for the research projects.In addition,a knowledge inference model based on representation learning is employed to achieve knowledge completion and improve the KG.Finally,experiments are conducted on the KG for research projects and the results demonstrate the effectiveness of the proposed method in enriching incomplete data within the KG. 展开更多
关键词 research projects knowledge graph(KG) KG completion
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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Lightweight deep network and projection loss for eye semantic segmentation
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作者 Qinjie Wang Tengfei Wang +1 位作者 Lizhuang Yang Hai Li 《中国科学技术大学学报》 北大核心 2025年第7期59-68,58,I0002,共12页
Semantic segmentation of eye images is a complex task with important applications in human–computer interaction,cognitive science,and neuroscience.Achieving real-time,accurate,and robust segmentation algorithms is cr... Semantic segmentation of eye images is a complex task with important applications in human–computer interaction,cognitive science,and neuroscience.Achieving real-time,accurate,and robust segmentation algorithms is crucial for computationally limited portable devices such as augmented reality and virtual reality.With the rapid advancements in deep learning,many network models have been developed specifically for eye image segmentation.Some methods divide the segmentation process into multiple stages to achieve model parameter miniaturization while enhancing output through post processing techniques to improve segmentation accuracy.These approaches significantly increase the inference time.Other networks adopt more complex encoding and decoding modules to achieve end-to-end output,which requires substantial computation.Therefore,balancing the model’s size,accuracy,and computational complexity is essential.To address these challenges,we propose a lightweight asymmetric UNet architecture and a projection loss function.We utilize ResNet-3 layer blocks to enhance feature extraction efficiency in the encoding stage.In the decoding stage,we employ regular convolutions and skip connections to upscale the feature maps from the latent space to the original image size,balancing the model size and segmentation accuracy.In addition,we leverage the geometric features of the eye region and design a projection loss function to further improve the segmentation accuracy without adding any additional inference computational cost.We validate our approach on the OpenEDS2019 dataset for virtual reality and achieve state-of-the-art performance with 95.33%mean intersection over union(mIoU).Our model has only 0.63M parameters and 350 FPS,which are 68%and 200%of the state-of-the-art model RITNet,respectively. 展开更多
关键词 lightweight deep network projection loss real-time semantic segmentation convolutional neural networks END-TO-END
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译林版英语新教材Project板块教学的实践探索
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作者 吴莹 李敏 《中小学英语教学与研究》 北大核心 2025年第10期20-23,共4页
译林新版小学英语教材中Project板块作为综合语言实践项目,对提升学生英语综合运用能力具有重要意义。本文在分析项目化学习特征及其对Project板块教学的指导意义的基础上,结合具体案例,探讨了如何从项目准备、项目实施和项目评价三方... 译林新版小学英语教材中Project板块作为综合语言实践项目,对提升学生英语综合运用能力具有重要意义。本文在分析项目化学习特征及其对Project板块教学的指导意义的基础上,结合具体案例,探讨了如何从项目准备、项目实施和项目评价三方面实施小学英语Project板块的教学。此外,本文还对如何更好地开展Project板块教学提出了相应的建议。 展开更多
关键词 小学英语 译林新版 project板块 项目化学习
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基于PROJECT BUS驱动的机械类本科生创新能力培养 被引量:6
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作者 蒙艳玫 卢福宁 +3 位作者 唐治宏 董振 陈远玲 陆冠成 《实验室研究与探索》 CAS 北大核心 2014年第2期194-198,共5页
研究了基于PROJECT BUS(项目总线)驱动的机械类本科生创新能力培养模式,以市场需求定制人才培养目标,以实验中心开放性实验室和本科生专业导师制为依托,以面向工程实际的产学研真实项目研发作为学习载体,将知识的拓展与项目研究开发过... 研究了基于PROJECT BUS(项目总线)驱动的机械类本科生创新能力培养模式,以市场需求定制人才培养目标,以实验中心开放性实验室和本科生专业导师制为依托,以面向工程实际的产学研真实项目研发作为学习载体,将知识的拓展与项目研究开发过程的迭代相结合,用项目研发的渐进思想与知识构建的思路相对应组织自主实践内容,通过项目BUS贯穿机械专业主干课程知识和创新能力培养过程的始终。有效解决了目前机械类本科生缺乏实际项目研发经验和团队合作精神,创新实践能力弱的关键问题,在理论研究和实践探索取得了显著成效。 展开更多
关键词 project BUS驱动 渐进式项目团队 金字塔型导师队伍 创新能力培养模式 机械类本科生
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基于Project Wise的选煤厂三维协同设计 被引量:10
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作者 黄波 韦彬 +3 位作者 陈绍东 高成龙 王宋 惠兵 《煤炭工程》 北大核心 2015年第4期30-32,共3页
选煤厂三维设计虽可有效提升设计效率和缩减设计成本,但选煤厂设计涉及专业面宽、工作量大,需各专业设计人员相互协同工作才能加快设计进度,提升设计质量。以煤炭工业郑州设计研究院对新田选煤厂设计过程为例,探讨了基于Project Wise平... 选煤厂三维设计虽可有效提升设计效率和缩减设计成本,但选煤厂设计涉及专业面宽、工作量大,需各专业设计人员相互协同工作才能加快设计进度,提升设计质量。以煤炭工业郑州设计研究院对新田选煤厂设计过程为例,探讨了基于Project Wise平台的选煤厂三维协同设计基本规范和步骤、选煤厂三维协同设计全生命周期支持和服务方法,说明了选煤厂三维协同设计的发展趋势。 展开更多
关键词 协同设计 选煤厂 三维设计 project WISE
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求解粒子群粒度分布的改进Projection算法 被引量:2
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作者 葛宝臻 马云峰 魏耀林 《光学精密工程》 EI CAS CSCD 北大核心 2012年第1期197-203,共7页
针对在激光粒度分布反演中由于迭代算法的迭代步长选取不当致使反演结果存在严重展宽和拖尾的问题,提出一种调整迭代步长的方法应用于Projection算法来提高测量精度。该方法首先基于测距相似度原理得到光能分布列向量与光能系数矩阵行... 针对在激光粒度分布反演中由于迭代算法的迭代步长选取不当致使反演结果存在严重展宽和拖尾的问题,提出一种调整迭代步长的方法应用于Projection算法来提高测量精度。该方法首先基于测距相似度原理得到光能分布列向量与光能系数矩阵行向量之间的相似度曲线,经滤波和归一化处理后得到被测粒子群的预测粒度分布;然后根据预测粒度分布结果确定迭代步长的大小。使用本文提出的改进Projection算法测量国家标准物质GWB(E)120046的D50误差为-0.6%、D10误差为-1.1%、D90误差为-0.6%,测量GWB(E)120041与GWB(E)120049混合标准物质的光能对数误差为2.167。测量结果表明,该算法可有效地提高算法的抗噪声能力、测量精度和分辨率。 展开更多
关键词 激光粒度仪 粒度分布测量 projection算法 迭代步长
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PDM系统与MS PROJECT系统集成研究和实践 被引量:1
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作者 曾芬芳 邵鲲 +1 位作者 李佑莉 严晓光 《机床与液压》 北大核心 2010年第17期15-17,共3页
分析PDM系统中项目管理与项目管理软件PROJECT系统集成的功能需求,在此基础上介绍两个系统之间的集成方案,并详细阐述此集成方案中的技术难点——PDM中的项目信息与PROJECT的MPP文件信息互动的实现方法。以KMPDM与PROJECT的集成为例说... 分析PDM系统中项目管理与项目管理软件PROJECT系统集成的功能需求,在此基础上介绍两个系统之间的集成方案,并详细阐述此集成方案中的技术难点——PDM中的项目信息与PROJECT的MPP文件信息互动的实现方法。以KMPDM与PROJECT的集成为例说明此集成方案的实现过程及应用效果。 展开更多
关键词 PDM 集成 project 项目管理
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数字时代的“文艺复兴”——Google Art Project引发的思考 被引量:4
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作者 汪彦君 《现代出版》 CSSCI 2011年第3期60-63,共4页
作为一种数字出版形态的虚拟博物馆,GoogleArtProject将全球各地17家博物馆的众多艺术品呈现于网络,并且运用谷歌街景等新技术将虚拟博物馆延伸到了公共艺术教育领域,也引发了关于交互方式、文化传播以及版权保护等话题的争议和思考。
关键词 GOOGLE ART project 虚拟博物馆 公共教育 资源共享 版权保护
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Projection算法在光谱法检测上皮组织发育异常中的应用
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作者 王清华 李振华 +1 位作者 来建成 贺安之 《光电工程》 EI CAS CSCD 北大核心 2008年第2期21-24,共4页
由散射光谱推知上皮组织发育异常属于一类反问题,此问题可转化为反演上皮组织细胞核的粒径变化。对上皮组织细胞核的单次散射偏振光谱进行数值模拟,并采用Projection迭代算法反演细胞核的粒径分布信息。Projection迭代算法将方程组的解... 由散射光谱推知上皮组织发育异常属于一类反问题,此问题可转化为反演上皮组织细胞核的粒径变化。对上皮组织细胞核的单次散射偏振光谱进行数值模拟,并采用Projection迭代算法反演细胞核的粒径分布信息。Projection迭代算法将方程组的解看成是多维空间的一个点,通过不断求解各超平面上的投影点而逼近真值。数值计算表明,Projection算法对于粒径呈单峰、双峰分布细胞核均有良好的反演精度,采用该法有望增加光谱法上皮组织发育异常诊断的灵敏度。 展开更多
关键词 projection算法 散射光谱 反问题 上皮组织
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基于Projection算法的激光粒度测试反演算法研究
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作者 王雪艳 刘缠牢 《应用光学》 CAS CSCD 北大核心 2011年第2期367-372,共6页
针对Projection迭代反演算法对噪声极其敏感,及在实际应用中造成粒度测量失真的问题,引入Vondrak数据平滑算法对Projection反演进行平滑处理。借助Visual C++6.0开发平台,编写测试软件对算法应用进行了仿真研究。通过分析比较平滑处理... 针对Projection迭代反演算法对噪声极其敏感,及在实际应用中造成粒度测量失真的问题,引入Vondrak数据平滑算法对Projection反演进行平滑处理。借助Visual C++6.0开发平台,编写测试软件对算法应用进行了仿真研究。通过分析比较平滑处理前后的反演结果,得出Vondrak数据平滑处理算法的引入有效提高了Projection反演的抗干扰性能。实验结果表明:基于Vondrak数据平滑处理的Projection反演结果能够反映粒度的真实分布,满足现代粉体工业粒度测量的稳定可靠、精度高、抗干扰能力强的要求。 展开更多
关键词 粒度反演算法 projection迭代反演算法 光能误差 Vondrak平滑
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Project Work在成人英语教学中的运用
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作者 陈军宏 《教育与职业》 北大核心 2004年第17期44-45,共2页
一、Project Work的涵义 Project Work是一种适于学生个人和小组在一节课或一段时间内进行专题讨论的具有调研特征的topic—centered活动。即在教师的指导下,学生对某一专题展开讨论,进行一系列的查阅、分析、判断等活动,然后将研究... 一、Project Work的涵义 Project Work是一种适于学生个人和小组在一节课或一段时间内进行专题讨论的具有调研特征的topic—centered活动。即在教师的指导下,学生对某一专题展开讨论,进行一系列的查阅、分析、判断等活动,然后将研究结果带回到课堂进行演示的一种教学模式。它从根本上改变了教师向学生单向的知识传授,而代之以学生与学生、教师与学生之间的探索与交流。 展开更多
关键词 project WORK 成人教育 英语 教学方式 分组讨论
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Hybrid alternate projection algorithm and its application for practical conformal array pattern synthesis
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作者 Fei Zhao Shunlian Chai +2 位作者 Huiying Qi Ke Xiao Junjie Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期625-632,共8页
Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is propose... Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is proposed for synthesizing the pattern of practical conformal array.The algorithm applies the variable direction aperture projection method with mutual coupling correction techniques to provide the good initial excitations of elements to the enhanced alternate projection algorithm(EAPA).In order to do further optimization,which improves the convergent speed of the algorithm significantly.Finally,the HAPA has been applied to the fabricated sector cylinder array with mutual coupling considered.The results of synthesized patterns,such as low sidelobe with null points formed pattern,beam scanning with low sidelobe pattern and the shaped beam pattern are presented.It demonstrates the validity of HAPA in practical conformal array synthesis. 展开更多
关键词 conformal array alternate projection algorithm aperture projection method pattern synthesis mutual coupling
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重要度驱动的自适应Projection Map在光子图中的应用
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作者 沈瑜 吕波 潘金贵 《计算机应用与软件》 CSCD 北大核心 2007年第7期3-4,38,共3页
在全局光照算法中,光子图算法是一种与视点无关的物空间辐射度近似计算方法,提出了一种基于重要度驱动采样的自适应Projection map算法,利用它可以在光子图算法中提高光子发射的有效性和准确性,加快渲染速度并取得更好的图像质量。实验... 在全局光照算法中,光子图算法是一种与视点无关的物空间辐射度近似计算方法,提出了一种基于重要度驱动采样的自适应Projection map算法,利用它可以在光子图算法中提高光子发射的有效性和准确性,加快渲染速度并取得更好的图像质量。实验表明,该算法能够有效地减少光源发射光子的次数,提高光子的命中率,具有相当的应用价值。 展开更多
关键词 projectION MAP PHOTON map光线跟踪 全局光照
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基于Project的虚拟维修拆装过程建模 被引量:14
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作者 黄涛 张豫南 +1 位作者 李瀚飞 田鹏 《系统仿真学报》 CAS CSCD 北大核心 2012年第1期192-196,共5页
分析虚拟维修拆装过程描述的复杂性,提出利用项目管理软件Microsoft Project建立维修拆装过程模型的方法。建立的过程模型主要包括:拆装结构模型、拆装资源模型和拆装运动模型。其中,利用了Project中WBS层次管理、设定任务优先级及任务... 分析虚拟维修拆装过程描述的复杂性,提出利用项目管理软件Microsoft Project建立维修拆装过程模型的方法。建立的过程模型主要包括:拆装结构模型、拆装资源模型和拆装运动模型。其中,利用了Project中WBS层次管理、设定任务优先级及任务链接等功能建立基于层次关系和关联关系的拆装结构模型;构造用于表现螺旋运动、直线运动和空间运动的三个描述公式,建立拆装运动模型。最后以某型坦克起动电机的拆卸为实例,说明建立的模型能很好地应用于维修拆装过程的描述,并且具有直观性。 展开更多
关键词 虚拟维修 拆装过程模型 项目管理软件 电气设备
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Scenario-based modeling and solving research on robust weapon project planning problems 被引量:5
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作者 XIA Boyuan ZHAO Qingsong +2 位作者 YANG Kewei DOU Yajie YANG Zhiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期85-99,共15页
Weapon project planning(WPP) plays a critical role in the process of national defense development and establishment of the future national defense force. WPP faces the backgrounds of various uncertainties, intense int... Weapon project planning(WPP) plays a critical role in the process of national defense development and establishment of the future national defense force. WPP faces the backgrounds of various uncertainties, intense inter-influence of weapon systems and involves modelling, assessment, and optimization procedures.The contents of this paper are mainly divided into three parts: first,the WPP processes are analyzed, and related elements are formulated to transform the qualitative problem to mathematics form;second, the value evaluation model of WPP solutions is proposed based on two criteria of total capability gap and total capability dispersion; third, two robustness optimization models are constructed based on the absolute robustness criterion and the robustness deviation criterion to support the robustness optimization process under multi-scenario. Finally, a case is studied to examine the feasibility and effectiveness of the proposed models and approaches. 展开更多
关键词 WEAPON project planning (WPP) uncertainty ROBUSTNESS MULTI-STAGE scenario.
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Analysis on decision-making model of plan evaluation based on grey relation projection and combination weight algorithm 被引量:12
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作者 ZHANG Zhicai CHEN Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期789-796,共8页
In military service joint operations, when there are more operational forces, more multifarious materials are consumed, the support is more complex and fuzzy, the deployment of personnel is more rapid, and the support... In military service joint operations, when there are more operational forces, more multifarious materials are consumed, the support is more complex and fuzzy, the deployment of personnel is more rapid, and the support provided by wartime military material support powers can be more effective. When the principles,requirements, influencing factors and goals of military material support forces are deployed in wartime, an evaluation indicator system is established. Thus, a new combined empowerment method based on an analytic hierarchy process(AHP) is developed to calculate the subjective weights, and the rough entropy method is used to calculate the objective weights. Combination weights can be obtained by calculating the weight preference coefficient error, which is determined by combining the cooperative game method and the minimum deviation into objectives. This approach can determine the grey relation projection coefficient and synthesize the measure scheme superiority to finally optimize the deployment plan using the grey relation projection decision-making method. The results show that the method is feasible and effective;it can provide a more scientific and practical decision-making basis for the military material support power deployment in wartime. 展开更多
关键词 method for grey relation projection decision-making military supply power in war deployment plan optimization ana-lytic hierarchy process (AHP) rough entropy method
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