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Effects of RapidEye Imagery's Red-edge Band and Vegetation Indices on Land Cover Classification in an Arid Region

Chinese Geographical Science 2017年第5期27卷 827-835页

作者： LI Xianju CHEN Gang LIU Jingyi CHEN Weitao cheng xinwen LIAO Yiwei College of Computer Science and Hubei Key Laboratory of Intelligent Geo-Information Processing China University of GeosciencesWuhan 430074China College of Marine Science and Technology China University of GeosciencesWuhan 430074China Laboratory of Geographic Information and Spatial Analysis Department of Geography and PlanningQueen's UniversityKingston ON K7L3N6Canada Faculty of Information Engineering China University of GeosciencesWuhan 430074China School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074China

Land cover classification(LCC) in arid regions is of great significance to the assessment, prediction, and management of land desertification. Some studies have shown that the red-edge band of RapidE ye images was effective for vegetation identification and could improve LCC accuracy. However, there has been no investigation of the effects of RapidE ye images' red-edge band and vegetation indices on LCC in arid regions where there are spectrally similar land covers mixed with very high or low vegetation coverage information and bare land. This study focused on a typical inland arid desert region located in Dunhuang Basin of northwestern China. First, five feature sets including or excluding the red-edge band and vegetation indices were constructed. Then, a land cover classification system involving plant communities was developed. Finally, random forest algorithm-based models with different feature sets were utilized for LCC. The conclusions drawn were as follows: 1) the red-edge band showed slight contribution to LCC accuracy; 2) vegetation indices had a significant positive effect on LCC; 3) simultaneous addition of the red-edge band and vegetation indices achieved a significant overall accuracy improvement(3.46% from 86.67%). In general, vegetation indices had larger effect than the red-edge band, and simultaneous addition of them significantly increased the accuracy of LCC in arid regions.

关键词： arid region land cover classification RapidEye red-edge band vegetation indices random forest Dunhuang Basin

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Resource Allocation for Throughput Maximization in Cognitive Radio Network with NOMA

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Computers, Materials & Continua 2022年第1期70卷 195-212页

作者： Xiaoli He Yu Song Yu Xue Muhammad Owais Weijian Yang xinwen cheng School of Computer Science Sichuan University of Science and EngineeringZigong643000China Department of Network Information Management Center Sichuan University of Science and EngineeringZigong643000China School of Information Engineering South West University of Science and TechnologyMianyang621010China School of Computer and Software Nanjing University of Information Science and TechnologyJiangsu210044China Alhamd Islamic University Airport Road Quetta BalochistanPakistan

Spectrum resources are the precious and limited natural *** order to improve the utilization of spectrum resources and maximize the network throughput,this paper studies the resource allocation of the downlink cognitive radio network with non-orthogonalmultiple access(CRN-NOMA).NOMA,as the key technology of the fifth-generation communication(5G),can effectively increase the capacity of 5G *** optimization problem proposed in this paper aims to maximize the number of secondary users(SUs)accessing the system and the total throughput in the *** the constraints of total power,minimum rate,interference and SINR,CRN-NOMA throughput is maximized by allocating optimal transmission ***,for the situation of multiple sub-users,an adaptive optimization method is proposed to reduce the complexity of the optimization ***,for the optimization problem of nonlinear programming,a maximization throughput optimization algorithm based on Chebyshev and convex(MTCC)for CRN-NOMA is proposed,which converts multi-objective optimization problem into single-objective optimization problem to *** the same time,the convergence and time complexity of the algorithm are *** analysis and simulation results show that the algorithm can effectively improve the system *** terms of interference and throughput,the performance of the sub-optimal solution is better than that of orthogonal-frequency-division-multiple-access(OFDMA).This paper provides important insights for the research and application of NOMA in future communications.

关键词： Resource allocation non-orthogonal multiple access cognitive radio network throughput maximization Chebyshev convex

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Target Extraction Study on the Vision System of Apple Picking Robot

Target Extraction Study on the Vision System of Apple Pickin...

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2013年中国智能自动化学术会议

作者： xinwen cheng XueQiang Shi Jiang cheng College China University of Geosciences4th FloorAdministrative Building Faculty of Information Engineering China University of Geosciences

This paper studied the color images of mature apple in natural environment,there is a general distinction between mature apple’s color and the *** and background distributed in different area of color space. According to this characteristic,this paper proposed an object extraction algorithm based on sample color *** we construct the sample color space in Lab space by using apple samples’ image and using mathematical morphology to optimized *** recognised the apple target according to the sample color space. For the small target of depth of field and serious keep out targets,we make them into binarized images and use morphology structure element again to processing *** last we got the ideal segmentation effect with high recognition rate.

关键词： Image segmentation Sample color space Binarization Mathematical morphology

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水库特征参数选择的多目标评价模型研究

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水力发电学报 2010年第2期29卷 127-131,138页

作者：黄晓荣成新文殷彤水资源与水电工程科学国家重点实验室(武汉大学) 武汉430072 四川大学水利水电学院成都610065 中国水电八局长沙410118

从水利、动能经济、防洪作用及淹没损失4方面建立水库特征参数评价指标体系,运用投影寻踪模型,把高维数据转换到低维子空间,同时运用实码加速遗传算法来优化投影指标函数和模型参数,获得指标体系最佳投影方向,进而揭示了高维数据的结构... 详细信息

从水利、动能经济、防洪作用及淹没损失4方面建立水库特征参数评价指标体系,运用投影寻踪模型,把高维数据转换到低维子空间,同时运用实码加速遗传算法来优化投影指标函数和模型参数,获得指标体系最佳投影方向,进而揭示了高维数据的结构特征,从而求得各指标的权重,以各项评价指标及其相应的模糊量值构造复合模糊物元,通过计算与标准模糊物元之间的欧氏贴近度,实现对推荐方案的综合评价。模型简洁、高效、可行,克服多目标各指标间的不可公度性所导致综合评价困难的瓶颈。

关键词：水资源特征参数优化多目标正常蓄水位

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无线自组织网络基于网格的匿名组播安全路由协议

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现代电子技术 2016年第6期39卷 89-94页

作者：曹海成新文四川理工学院计算机学院四川自贡643000

已有的无线自组织网络匿名算法大多针对某个阶段或步骤,对此提出一种基于网格的匿名组播安全路由协议。首先,为簇首发送网络管理消息设置了随机的发送间隔,降低被窃听的成功率;然后,为自组织网络的各种消息设计了统一的消息格式,以免窃... 详细信息

已有的无线自组织网络匿名算法大多针对某个阶段或步骤,对此提出一种基于网格的匿名组播安全路由协议。首先,为簇首发送网络管理消息设置了随机的发送间隔,降低被窃听的成功率;然后,为自组织网络的各种消息设计了统一的消息格式,以免窃听者通过格式分析获得有效的信息;最后,基于网格对无线网络的分簇与路由进行管理,新节点加入簇时,无需向簇首发送请求即可与簇内成员建立有效的链接与路由,由于该算法考虑了整个网络生命期,因此可全面地保证网络的匿名性与安全性。仿真实验结果表明,该方法使得移动自组织网络具有较好的连接性与隐私保护能力。

关键词：移动自组织网络无线传感器网络匿名组播协议安全路由协议无线网格网络

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苹果采摘机器人视觉系统的目标提取研究

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农机化研究 2013年第10期35卷 46-48,59页

作者：石雪强程新文中国地质大学(武汉)信息工程学院武汉430074 中国地质大学江城学院武汉430200

研究了自然环境下的成熟苹果彩色图像,结果表明:成熟苹果颜色与背景色大都存在明显差异。从颜色空间角度来说,目标和背景分布于不同的区域。根据这一特点,提出了基于样本颜色空间的目标提取算法。首先,由苹果样本图像在L*a*b*空间中构... 详细信息

研究了自然环境下的成熟苹果彩色图像,结果表明:成熟苹果颜色与背景色大都存在明显差异。从颜色空间角度来说,目标和背景分布于不同的区域。根据这一特点,提出了基于样本颜色空间的目标提取算法。首先,由苹果样本图像在L*a*b*空间中构建样本颜色空间,并用数学形态学对样本颜色空间进行优化;然后,依据样本颜色空间对苹果彩色图像进行目标识别,对于远景深小目标物和严重遮挡的目标物,在样本空间识别的基础上进行二值化,运用形态学结构元素法进行处理;最后,得到了理想的分割效果,识别率高。

关键词：苹果采摘机器人视觉系统图像分割样本颜色空间二值化处理数学形态学

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STUDIES ON THE REPRODUCTIVE AND DIGESTIVE ORGANS OF NASAAL BOT FLY（OESTRUS OVIS）

STUDIES ON THE REPRODUCTIVE AND DIGESTIVE ORGANS OF NASAAL B...

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面向21世纪的动物科学与动物医学国际研讨会

作者： Bo xinwen cheng Zhirong Zheng Jinghong Xu Xueping Zhang Xingya (Xinjiang Academy of Agricultural Reclamation Xinjiang Shihezi 832000)

＜正＞Features of some organ structures including reproductive and digestive system and reproductive development after emerging about adult of nasal bot fly（Oestrus ovis） are observed by using insect dissect and slide-making and slice tissue. The results are summarized as follows: 1. The quantity ofoverioles is not fixed, and its arrangement within a ovary seems to be irregular. 2. The peak of eggs production in the uterus occured after 5 days of emerging. 3. The adult has a digestive system degenerated but have a relatively developed excretory system, which is consist of four mulpighian tubules connecting with hind gut and rectum. Lastly, the possibility is discussed that the reproductive systems of some flies is similar to Oestrus ovis

关键词： Oestrus ovis adult reproductive organ digestive system

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基于图斑的高分辨率遥感影像变化检测

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测绘通报 2009年第8期 17-20页

作者：赖祖龙申邵洪程新文张洁中国地质大学信息工程学院湖北武汉430074 武汉大学遥感信息工程学院湖北武汉430079 中国地质大学资源学院湖北武汉430074

高分辨率影像具有空间分辨率高、光谱分辨率相对不足的特点,传统基于像元的变化检测方法在高分辨率遥感变化检测中显示出不足。研究一种基于图斑的多时相高分辨率影像变化检测方法,以光谱特征为依据,对影像进行分割,然后以图斑为基本分... 详细信息

高分辨率影像具有空间分辨率高、光谱分辨率相对不足的特点,传统基于像元的变化检测方法在高分辨率遥感变化检测中显示出不足。研究一种基于图斑的多时相高分辨率影像变化检测方法,以光谱特征为依据,对影像进行分割,然后以图斑为基本分析单元进行变化检测研究。引入概率统计学中的t检验方法,并与相关系数法相结合,采用区域内的光谱、纹理特征进行变化检测。选取城市区域的高分辨率影像进行试验,结果表明该方法可以很好地实现高分辨率影像的变化检测,具有一定的理论研究和实际应用价值。

关键词：影像分割纹理相关系数 t检验

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内皮素与糖尿病视网膜病变的相关性分析

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中国卫生标准管理 2014年第20期5卷 81-82页

作者：程新文中国重型汽车集团公司医院山东济南250000

本文选取了我院的相关患者资料进行了回顾性分析。研究结果证实:糖尿病患者的内皮素水平升高与糖尿病视网膜病变的发生和发展密切相关,糖尿病患者的内皮素水平可反映糖尿病视网膜病变的发展程度。

关键词：内皮素糖尿病视网膜病变相关性

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A study of real-time tide measurement

A study of real-time tide measurement

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The 2nd International Conference on Environmental and Engineering Geophysics

作者： Gang Chen xinwen cheng Jianhu Zhao School of Engineering China University of Geosciences Wuhan 430074 China School of Geomatics and Geodesy Wuhan University Wuhan 430079 China

＜正＞Tidal level plays a very important role in hydrographic survey for providing a vertical reference surface. Conventional tide measurement only generates a separate tide at each tide gauge, and can not meet completely with the requirement of continuous, precise and dynamitic hydrographic survey. It is necessary to look for a new method to acquire real-time tidal level when surveying vessel is cruising. The high continuity and credibility of GPS carrier phase differential technique can provide a possibility to overcome these shortcomings of the conventional method. In the paper, the GPS tidal level is acquired finally by time offset （delay） correction, attitude correction, height transformation, draft correction and a data filter. Time offset correction ensures attitude parameters derived from multibeam sounding system synchronization with GPS vertical solution. Attitude correction can eliminate the effect of attitude and transfer the height of GPS antenna to reference point （RP）. In order to calculate the instantaneous height of water surface, a draft correction also should be added into the correction. Tidal level should be a stable water surface within short time period. Thus, a low-pass filter needs to be implemented for the elimination of noise and the extraction of the long-period tidal level. By above processing, Finally, GPS tide solution is achieved. The kinematical GPS tidal level measurement method is implemented in an experiment. RTK and PPK are adopted in the experiment. GPS tide solutions and the tidal level observed at tide gauges are compared and analysed in the paper. The statistic result of the difference between the two tidal level solutions shows that GPS tidal level solutions have less than ±3 centimetres of standard bias with respect to tidal readings, and also proves that the methods of GPS real-time tide measurement and corresponding data processing are feasible and credible.

关键词： RTK (Real Time Kinematic) PPK (Post Processing Kinematic) tidal level height transformation

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