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1.
为提高赤潮预警系统的准确性,最大限度降低赤潮灾害所带来的损失,研究并提出一种融合分层凝聚TS模糊推理集成模型的赤潮预测算法。首先,借鉴分类预测和数值预测在赤潮预测过程中各自优点,提出采用模糊推理算法实现数值预测,采用分层凝聚算法实现分类预测的算法框架;然后,为提高模糊推理算法的预测精度,提出一种基于经验规则和现实规则的改进TS模糊规则提取算法对模糊推理过程进行设计。通过在烟台四十里湾赤潮监测数据上的仿真对比显示,该算法的预测准确度要优于LMBP算法,显示了该算法的有效性。  相似文献   

2.
中国的赤潮研究   总被引:29,自引:0,他引:29       下载免费PDF全文
赤潮 (有害藻华 )这种海洋灾害已引起了世界各国政府和科学家的重视。近年来我国赤潮的发生频率、规模和面积不断增大 ,对我国沿海养殖业、渔业资源、渔产品质量、生态环境以及人类健康构成了重大的危害和威胁 ,严重影响了沿海经济。因此 ,加强与赤潮相关的生态学与海洋学研究 ,才能认识赤潮的发生机制 ,并结合建立的监测网络 ,进行赤潮灾害预报预警 ,对减少赤潮的危害 ,保障我国沿海经济的持续发展 ,具有十分重要意义。  相似文献   

3.
针对单一的赤潮特征提取算法在对赤潮遥感图像进行特征提取时还存在准确性不高等问题,本文提出了一种基于多特征的赤潮遥感提取算法,首先对加权平均方法进行改进,提出了自适应加权平均算法,对遥感图像的叶绿素浓度特征进行提取,然后采用偏差系数对水体固有光学模型进行参数优化,对遥感图像的光谱特征进行提取。实例仿真试验结果表明,本文提出的基于多特征的赤潮遥感提取算法相比较单一的光谱特征提取算法,具有较高的赤潮特征提取准确性和稳定性。  相似文献   

4.
张亮  陈泳任  李杰 《内江科技》2013,34(3):161-162
机场鸟情预测预报具有复杂性和分布性的特点,传统的面向结构和对象的方法已经不能给出一个描述系统行为以及互相之间信息交换的统一模型。论文采用面向Agent信息系统建模方法将现实世界看做多个具有自主行为的实体,提出了基于多Agent的中国机场鸟情预测预报系统的组织形式,即中央鸟情预测预报管理中心Agent、区域鸟情预测预报管理中心Agent和三级鸟情预测预报管理Agent。详细描述了各个Agent的功能以及之间的工作方式和合作机制,为中国机场鸟情预测预报系统的建立提供了理论依据。  相似文献   

5.
太阳能预报方法及其应用和问题   总被引:3,自引:2,他引:3  
太阳能预报包括预测太阳辐射量和光伏发电功率,对光伏发电系统并网运行有重要意义,是当前太阳能开发利用的一个关键问题。本文对国内外太阳能预报方法进行了扼要的评述,归纳了太阳能预报的机理及其方法在光伏发电中的应用。太阳辐射的预报方法主要有传统统计、神经网络、卫星遥感和数值模拟等方法。文中基于光伏发电应用的需求,分析了不同预报方法的优点和不足,并探讨了若干有待进一步改善的问题,展望了国内太阳能预报技术方法的发展和应用前景。  相似文献   

6.
采用不同的损失函数和罚函数构建了广义指数预报因子模型,用该模型来预测国际黄金价格.构建方法包括:1)岭估计方法;2)基于L1、L2以及二者结合的损失函数LM,利用LASSO和SCAD 2种罚函数选取不同参数EWMA的线性组合作为预报因子.实证检验表明,该方法构建的模型有效改进了单参数EWMA预测模型,其预测精度优于已有方法.  相似文献   

7.
由于风力发电依靠的风力具有较大的不可控性,引起风电的加入对电网调度提出了较高的要求,因此对风能进行预测具有十分重要的作用。本文提出了一种基于集成神经网模型的风能预报方法,该方法将传统的单一模型回归预测转变为多种条件多神经网的共同回归预测,并集成回归结果作为风能预测的最终值。实验表明,本文提出的方法提高了预测的精度与稳定性,较传统方法具有更高的实用价值。  相似文献   

8.
鸟击是当今航空运输业重大灾害之一。鸟击航空器所造成的经济损失每年超过百亿元,成为全世界难以应对的课题。因此,了解鸟类的生物学特性,掌握其活动规律,及时做好鸟击灾害的预测预报,是鸟击防灾的重要环节。本文对鸟击防灾预测预报的依据、分类、方法、准确度的评估进行了详细说明,并对短期预测预报的具体方法进行了举例,为鸟击综合治理提供了理论、实践方法和依据。  相似文献   

9.
为进一步加强森林病虫害预防工作,强化对森林病虫害预测预报工作的管理,提高预报和防治成效。本文对森林害虫发生期预测方法进行分析。  相似文献   

10.
《科技风》2017,(14)
本文提出了一种基于自回归模型和误差动态修订相结合的风电场短期风速预报方法。通过对张北单晶河某风电场70m测风塔2017年1-3月逐15min风速数据分析,发现该方法在风速短期预报中效果明显:对未来单步和4步风速预测中,与实测值相关性分别为0.9和0.8,平均绝对误差分别为0.8m/s和1.3m/s,均方根误差分别为1.3m/s和1.8m/s,预报结果较为理想,随预报步数的增加,预报误差逐渐增大。结果表明,新的预报方法是一种有效且简单易行的风电场风速短期预报方法。  相似文献   

11.
浙江海区赤潮发生前期气象因子的统计分析   总被引:6,自引:0,他引:6  
邓素清  汤燕冰 《科技通报》2005,21(4):386-391
本文利用2002年5~6月的赤潮纪录,及逐日的温度、气压和降水等气象要素实测资料。分析了浙江海域赤潮发生前期有关气象要素的变化特点;以及赤潮发生时,不同气象因子分布的统计特征。结果表明:浙江海域赤潮的发生有明显的地域特征,在不同海区,利于赤潮发生的气象条件是不同的。  相似文献   

12.
Research on the adoption of systems for big data analytics has drawn enormous attention in Information Systems research. This study extends big data analytics adoption research by examining the effects of system characteristics on the attitude of managers towards the usage of big data analytics systems. A research model has been proposed in this study based on an extensive review of literature pertaining to the Technology Acceptance Model, with further validation by a survey of 150 big data analytics users. Results of this survey confirm that characteristics of the big data analytics system have significant direct and indirect effects on belief in the benefits of big data analytics systems and perceived usefulness, attitude and adoption. Moreover, there are mediation effects that exist among the system characteristics, benefits of big data analytics systems, perceived usefulness and the attitude towards using big data analytics system. This study expands the existing body of knowledge on the adoption of big data analytics systems, and benefits big data analytics providers and vendors while helping in the formulation of their business models.  相似文献   

13.
Businesses have begun using IT apps for a variety of reasons in recent years. The rapid advancement of new technologies has opened up vast prospects for businesses to digitise their operations, enhance their use of information systems, and compete more effectively in the global marketplace. Information technology (IT) businesses can benefit greatly from Big Data analytics due to the depth and breadth of their data analysis. Big data can be used to examine IT departments in the following ways: performance analysis, forecast maintenance, security analysis, and resource analysis. When it comes to boosting their business's dependability, speed, quality, and effectiveness, most companies rely on big data. Companies can gain a competitive edge thanks to the massive amounts of data that big data is able to collect, store, and manage. Big data analytics is being used by a growing number of businesses to make sense of their mountain of data. In this paper, we examine the ways in which IBM, TCS, and Cognizant use big data within their operations. Long-term planning strategies and business intelligence practises are also suggested in this research as means of protecting personal information.  相似文献   

14.
针对赤潮生物提出具有较高准确率的实时自动分类方法,本文提出采用ReliefF-SBS进行特征选择,即针对赤潮生物图像原始数据集进行特征分析,并在此基础上,对原始特征集进行特征选择以去除特征集中的无关特征和冗余特征,得到最优特征子集,减少它们对分类器分类精度的影响。文中给出了实验结果和分析,同时验证了对k-Nearest Neighbor algorithm(KNN)和Support Vector Machine(SVM)分类器分类效果的影响。  相似文献   

15.
TC灾情评估分析及减灾对策   总被引:2,自引:0,他引:2  
对比分析0216号台风Sinlaku、9417号台风Fred、9909号热带风暴Wendy等20世纪90年代以来3个“著名”热带气旋(TC)对温州造成的灾情评估指数和灾情指数,发现:Sinlaku的灾情指数大大低于同样在温州登陆、同样时逢天文大潮、强度、路径相似、灾情评估指数相近的台风Fred的灾情指数,甚至明显低于灾情评估指数定义为中灾的9909号热带风暴Wendy。说明气象预报的准确及时与科学的防御减灾措施可以非常有效地降低自然灾害造成的经济损失及对社会发展的负面影响。文中提出了一些减灾对策,可供政府和有关部门参考。  相似文献   

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18.
The mechanism of business analytics affordances enhancing the management of cloud computing data security is a key antecedent in improving cloud computing security. Based on information value chain theory and IT affordances theory, a research model is built to investigate the underlying mechanism of business analytics affordances enhancing the management of cloud computing data security. The model includes business analytics affordances, decision-making affordances of cloud computing data security, decision-making rationality of cloud computing data security, and the management of cloud computing data security. Simultaneously, the model considers the role of data-driven culture and IT business process integration. It is empirically tested using data collected from 316 enterprises by Partial Least Squares-based structural equation model. Without data-driven culture and IT business process integration, the results suggest that there is a process from business analytics affordances to decision-making affordances of cloud computing data security, decision-making rationality of cloud computing data security, and to the management of cloud computing data security. Moreover, Data-driven culture and IT business process integration have a positive mediation effect on the relationship between business analytics affordances and decision-making affordances of cloud computing data security. The conclusions in this study provide useful references for the enterprise to strengthen the management of cloud computing data security using business analytics.  相似文献   

19.
The number of firms that intend to invest in big data analytics has declined and many firms that invested in the use of these tools could not successfully deploy their project to production. In this study, we leverage the valence theory perspective to investigate the role of positive and negative valence factors on the impact of bigness of data on big data analytics usage within firms. The research model is validated empirically from 140 IT managers and data analysts using survey data. The results confirm the impact of bigness of data on both negative valence (i.e., data security concern and task complexity), and positive valence (i.e., data accessibility and data diagnosticity) factors. In addition, findings show that data security concern is not a critical factor in using big data analytics. The results also show that, interestingly, at different levels of data security concern, task complexity, data accessibility, and data diagnosticity, the impact of bigness of data on big data analytics use will be varied. For practitioners, the findings provide important guidelines to increase the extent of using big data analytics by considering both positive and negative valence factors.  相似文献   

20.
Data-driven campaigning has been in the spotlight over several years. Yet, we still have a limited understanding of political data analytics companies: how they envision data analytics and voter targeting, their role in electoral processes and what promises they make to their clients. This article focuses on the way in which such issues are conceived of in the marketing rhetoric of the political data analytics industry. Drawing on a sample of 19 political data analytics companies it systematically explores the ways in which data analytics is envisioned and marketed as a powerful tool in electoral processes, exposing a fundamental disconnect between scholarly discourse on the one hand – often critical of the claims of these companies about the efficacy of their methods – and a highly functionary data imaginary on the other hand, actively fostered by the political data-analytics industry and the media.  相似文献   

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