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1.
In order to solve the problem of UAV’s direction perception and collision prevention in the limited radio communication environment, we use wireless ultraviolet (UV) communication as an auxiliary communication method in UAVs. We improve the traditional artificial potential field (APF) method, design a UV- MIMO model installed on the UAV, and propose the improved artificial potential field (IAPF) method. On this basis, the determination of the threat source direction in IAPF algorithm is further simplified, and the improved artificial potential field based on ultraviolet MIMO (IAPF-UVMIMO) algorithm is proposed. Experimental results show that IAPF effectively solves the problems of unreachable targets, path oscillations and local minimums that exist in the traditional artificial potential field method. In addition, IAPF-UVMIMO also improves the tolerance of the threat source direction. Compared with IAPF, the number of collisions with actual collision threats is reduced by 22.6%.  相似文献   
2.
光谱颜色复现和色度精度是评价光谱重建算法准确的基础。简单而直观的评价指标对颜色复现控制是必不可少。该指标需要同时表征复现颜色的光谱差和色度差。在研究光谱匹配评估的方法基础上,提出基于颜色视觉感知的三种光谱评估指标,通过加权人眼视觉匹配函数,实现颜色光谱差与色度的评估。通过孟塞尔颜色系统的光谱数据,该论文分析与验证三种视觉加权的评估指标的有效性。通过孟塞尔颜色系统数据,这些指标在CIELab均匀色空间中分布均匀而稳定,从而证明加权算法的评估指标是既表征到颜色感知又反映出颜色的光谱相似度。实证结果表明,加权的指标可以实现同时表征实际人眼的颜色感知和颜色光谱差异。基于人眼视觉感知的评估指标解决了颜色的原始光谱和重建光谱的光谱匹配精度的定量评价问题。所提出评价指标通过一个简单而直观的数值实现对复现颜色光谱与色度评估。  相似文献   
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Community structure detection in complex networks has been intensively investigated in recent years. In this paper, we propose an adaptive approach based on ant colony clustering to discover communities in a complex network. The focus of the method is the clustering process of an ant colony in a virtual grid, where each ant represents a node in the complex network. During the ant colony search, the method uses a new fitness function to percept local environment and employs a pheromone diffusion model as a global information feedback mechanism to realize information exchange among ants. A significant advantage of our method is that the locations in the grid environment and the connections of the complex network structure are simultaneously taken into account in ants moving. Experimental results on computer-generated and real-world networks show the capability of our method to successfully detect community structures.  相似文献   
5.
新兴社会化商务社会中人与人之间的高交互性及推荐信息的海量化和高动态性,对平台分析消费者感知信任提出了新的挑战。然而,对推荐信息进行聚类难以体现消费者主观性及主体间关系。本文将感知推荐信任聚类问题转化为复合网络划分问题,将主观逻辑方法与基于Normal矩阵的谱平分方法相结合构建社会化商务中消费者感知推荐信任的聚类方法。首先,将推荐信息转化为感知推荐信任,然后,从社交网络中抽取感知推荐信任相似度与关系亲密度网络,并构建Normal矩阵用谱平分方法进行划分。最后,通过多组仿真实验证明了该方法的实用性和有效性。该方法能够为社会化商务中消费者信任的分析提供新视角,为平台制定精准化营销策略提供支持。  相似文献   
6.
探讨煤矿企业愿景认同的影响因素,对提高企业凝聚力,实现煤矿企业可持续发展具有重要意义.基于大同煤矿集团有限责任公司下属3矿矿工的问卷调查,通过建立二元Logistic回归模型,分析了影响企业愿景认同的关键因素.在得出教育程度的高低对愿景认同度具有正向作用,但月收入的高低无显著影响;制度保障对愿景认同度具有正向作用,尤其是工作考核的合理性与选拔人才的公正性对愿景认同的影响显著,但食住保障满意度对愿景认同无显著影响两个结论的同时,进一步认证了"支持型文化对愿景认同度具有显著的正向作用,但科层型文化影响不显著"研究成果.  相似文献   
7.
非自愿移民在获得移民补偿后仍面临着贫困及生活不稳定等问题,这种问题产生的原因是补偿不合理,提供了一种新的移民补偿思路,那就是根据移民的风险感知能力构建多目标规划模型,并运用模拟数据验证,经检验模型能够用于为移民提供一种多元补偿组合方案,使移民能够获得未来的财产收入,是一种长效的补偿思路.  相似文献   
8.
21世纪是一个信息化时代,为了更好的面向信息化战争.通过对传统的兰切斯特微分方程进行改进,考虑了信息化的诸多因素,引入了战场情报感知系数和信息优势系数.构建了数学模型,并对其进行差分处理求解,比较分析了交战双方对战场感知系数变化和信息优势系数变化情况下,对战争的影响.以海湾战争为例,检验了模型的可行性.  相似文献   
9.
Graphics play a crucial role in statistical analysis and data mining. Being able to quantify structure in data that is visible in plots, and how people read the structure from plots is an ongoing challenge. The lineup protocol provides a formal framework for data plots, making inference possible. The data plot is treated like a test statistic, and lineup protocol acts like a comparison with the sampling distribution of the nulls. This article describes metrics for describing structure in data plots and evaluates them in relation to the choices that human readers made during several large Amazon Turk studies using lineups. The metrics that were more specific to the plot types tended to better match subject choices, than generic metrics. The process that we followed to evaluate metrics will be useful for general development of numerically measuring structure in plots, and also in future experiments on lineups for choosing blocks of pictures. Supplementary materials for this article are available online.  相似文献   
10.
Gibberellins (GAs) are phytohormones essential for many developmental processes in plants. In this work, fundamental mechanism of hormone perception by receptor GID1 has been studied by performing computational simulations, revealing a new GA‐binding channel of GID1 and a novel hormone perception mechanism involving only one conformational state of GID1. The novel hormone perception mechanism demonstrated here is remarkably different from the previously proposed/speculated mechanism [Murase et al., Nature 2008 , 456, 459] involving two conformational states (“OPEN” and “CLOSED”) of GID1. According to the new perception mechanism, GA acts as a “conformational stabilizer,” rather than the previously speculated “allosteric inducer,” to induce the recognition of protein DELLA by GID1. The novel mechanistic insights obtained in this study provide a new starting point for further studies on the detailed molecular mechanisms of GID1 interacting with DELLA and various hormones and for mechanism‐based rational design of novel, potent growth regulators that target crops and ornamental plants. © 2013 Wiley Periodicals, Inc.  相似文献   
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