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基于灰体模型的东北亚安全局势分析
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作者 闫倩 苏力德 +1 位作者 周其琨 张楠 《海外文摘》 2021年第21期25-26,共2页
国家安全是实现中华民族伟大复兴的重要保障,我国作为东北亚地区的一员,东北亚地区安全对我国的发展有着十分重要的战略意义。本文用“存在风险的安全稳定”对东北亚安全形势做了高度概括,用有别于“黑体模型”或“白体模型”的“灰体... 国家安全是实现中华民族伟大复兴的重要保障,我国作为东北亚地区的一员,东北亚地区安全对我国的发展有着十分重要的战略意义。本文用“存在风险的安全稳定”对东北亚安全形势做了高度概括,用有别于“黑体模型”或“白体模型”的“灰体模型”进行表达和描述。最后指出,相对于西方现有安全观的不足,中国提出的具有开放、包容的“亚洲安全观”为东北亚安全发展点亮了一盏指向未来的明灯。 展开更多
关键词 东北亚安全 灰体模型 安全困境 “重心三角形”三边关系 中国智慧
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细水雾衰减目标热辐射的谱带-灰体模型
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作者 杜永成 杨立 孙丰瑞 《工程热物理学报》 EI CAS CSCD 北大核心 2014年第11期2252-2255,共4页
在火灾防护中为提高热辐射传输计算的效率,建立了多分散细水雾0.8~20μm辐射特性参数数据库,并提出了两种谱带一灰体模型。本文中,辐射特性参数采用数据库调用的方法获取,而细水雾非灰特性采用谱带一灰体模型处理。通过所建三种模型的... 在火灾防护中为提高热辐射传输计算的效率,建立了多分散细水雾0.8~20μm辐射特性参数数据库,并提出了两种谱带一灰体模型。本文中,辐射特性参数采用数据库调用的方法获取,而细水雾非灰特性采用谱带一灰体模型处理。通过所建三种模型的相对误差和计算效率分析,发现灰体假设模型的相对误差较大,且随水雾光学厚度的增大而增大;而谱带一灰体模型具有很好的精度。总体讲,谱带模型具有最好的精度,但效率最差;灰体假设模型效率最高,但精度最差;只有谱带一灰体模型既兼顾了效率又兼顾了精度。 展开更多
关键词 细水雾 热遮蔽 辐射特性参数 谱带-灰体模型
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强冲击作用下含能粉体DAAF的热点光辐射特征
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作者 聂群朋 张岱宇 《西南科技大学学报》 CAS 2024年第3期30-35,56,共7页
为探究强冲击作用下含能粉体中热点密度的生成与发展,采用二级轻气炮系统对含能粉体二氨基偶氮呋咱(Diaminofurazan,DAAF)进行冲击,通过辐射高温计观测同一冲击条件下不同厚度的DAAF粉体中热点辐射特征,采用普朗克公式拟合灰体模型得到D... 为探究强冲击作用下含能粉体中热点密度的生成与发展,采用二级轻气炮系统对含能粉体二氨基偶氮呋咱(Diaminofurazan,DAAF)进行冲击,通过辐射高温计观测同一冲击条件下不同厚度的DAAF粉体中热点辐射特征,采用普朗克公式拟合灰体模型得到DAAF粉体在速度为1.6 km/s飞片冲击下的表观温度与发射率。结果表明:冲击DAAF粉体的热点生成温度约为3950 K,并在200 ns的时间尺度内呈现一定的冷却态势,且随着样品的厚度增加热点发展更为充分,在最厚的样品中热点聚集更加明显;在200 ns时间尺度内,样品的发射率呈现增加态势且随着样品的厚度增加呈递增趋势。在冲击速度1.6 km/s下,0.645 mm厚度DAAF样品存在爆燃现象。 展开更多
关键词 含能粉 DAAF热点 光辐射 灰体模型
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云的红外辐射模型综述 被引量:1
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作者 郭新军 金伟其 +1 位作者 高稚允 王霞 《光学技术》 CAS CSCD 2003年第3期341-343,共3页
介绍了云的分类和组成,以及云的红外辐射模型(包括二流近似、灰体近似和黑体近似模型),测量了云的红外光谱辐射。分析表明:二流近似模型可用于云层对太阳和大气中红外波段的反射、透射和云自身的辐射。黑体近似模型和灰体近似模型主要... 介绍了云的分类和组成,以及云的红外辐射模型(包括二流近似、灰体近似和黑体近似模型),测量了云的红外光谱辐射。分析表明:二流近似模型可用于云层对太阳和大气中红外波段的反射、透射和云自身的辐射。黑体近似模型和灰体近似模型主要用于对云层较粗略的估算,灰体模型可近似描述8~12μm波段的辐射,且形式上比较简单,是一种常用的简化模型。 展开更多
关键词 红外辐射模型 二流近似模型 近似模型 近似模型 反射比 透射比 辐射率
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多分散细水雾遮蔽热辐射的高效计算方法 被引量:1
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作者 杜永成 杨立 +1 位作者 谢志辉 孙丰瑞 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2014年第4期436-441,共6页
建立了多分散细水雾0.8~20μm辐射特性参数数据库和谱带-灰体模型,并提出了采用数据库调用获取辐射特性参数、采用谱带-灰体模型处理细水雾非灰特性相结合的方法.通过将该方法计算的无量纲辐射热流与采用Mie理论和窄谱带模型计算的结果... 建立了多分散细水雾0.8~20μm辐射特性参数数据库和谱带-灰体模型,并提出了采用数据库调用获取辐射特性参数、采用谱带-灰体模型处理细水雾非灰特性相结合的方法.通过将该方法计算的无量纲辐射热流与采用Mie理论和窄谱带模型计算的结果作对比,证明该方法准确可靠.通过精度分析和效率分析,证明所提方法既可保证精度在可接受的水平,又能使计算时间大幅缩减. 展开更多
关键词 多分散细水雾 热遮蔽 辐射特性参数 谱带-灰体模型 数据库
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LOCALIZATION OF OBJECT (SPINE) IN MEDICAL IMAGE USING ACTIVE SHAPE MODELS 被引量:2
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作者 徐涛 蔡宇新 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期211-217,共7页
Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is base... Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is based on the assumption of one-dimensional sampling and searching method. In this work a new way to model the gray-level appearance of the objects is explored, using a two-dimensional sampling and searching technique in a rectangular area around each landmark of object shape. The ASM based on this improvement is compared with the original ASM on an identical medical image set for task of spine localization. Experiments demonstrate that the method produces significantly fast, effective, accurate results for spine localization in medical images. 展开更多
关键词 object localization active shape models (ASM) gray-level appearance model principal component analysis SPINE
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图像光谱技术实现精确测温 被引量:3
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作者 李耀 戴长建 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第1期38-41,共4页
建立了一种以灰体辐射为基础测量温度的新方法,它不仅可以测定辐射体的实时温度,而且可以实现无接触和高精度测量。首先,利用多通道CCD图像光谱仪精确测量辐射体在较宽波段内的辐射光谱,作为该辐射体的指纹光谱,将其定义为一个等效的灰... 建立了一种以灰体辐射为基础测量温度的新方法,它不仅可以测定辐射体的实时温度,而且可以实现无接触和高精度测量。首先,利用多通道CCD图像光谱仪精确测量辐射体在较宽波段内的辐射光谱,作为该辐射体的指纹光谱,将其定义为一个等效的灰体;其次,通过对所测光谱的拟合确定该辐射体的灰体辐射模型的系数,从而确定待测辐射体的灰体辐射模型;最后,通过光谱技术与灰体辐射模型的结合确定给定辐射体的任意温度。通过对无火焰和有火焰这两类热辐射体的实验检验,表明该测温方法具有实时、准确和无接触等优点。 展开更多
关键词 辐射模型 CCD图像光谱 光谱测温技术 能级跃迁
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An effective method for performance evaluation of ACLS based on improved grey analytic hierarchy
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作者 LI Yan YIN Haitao 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第2期166-172,共7页
The performance evaluation of automatic carrier landing system(ACLS)is an important part in the field of carrier aircraft landing control.Combining grey analytic hierarchy theory and data normalization theory,an impro... The performance evaluation of automatic carrier landing system(ACLS)is an important part in the field of carrier aircraft landing control.Combining grey analytic hierarchy theory and data normalization theory,an improved grey analytic hierarchy method is introduced to evaluate the performance of ACLS.A complete performance evaluation indicators system of ACLS is established,and the definition and calculation formula of each indicator are provided.The grey analytic hierarchy model is modified to improve the real-time performance of the algorithm,where traditional expert scoring sampling matrix is substituted by an indicator normalized sample matrix.Taking a certain ACLS as an example,the experimental simulation is carried out,and the simulation results verify the reliability and the accuracy of the improved grey analytic hierarchy method. 展开更多
关键词 automatic carrier landing system(ACLS) evaluation indicators system grey analytic hierarchy model normalization sample matrix
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A Decision Model Based on Grey Rough Sets Integration with Incomplete Information 被引量:5
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作者 HOU Ya-lin LUO Dang 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期151-158,共8页
In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete... In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete information is proposed. We put forward incidence degree coefficient formula for grey interval, by information entropy theory and analysis technique, the method and principle is presented to fill up null values. We also establish the method of grey interval incidence cluster. Because grey system theory and Rough set theory are complementary each other, decision table with preference information is obtained by the result of grey incidence cluster. An algorithm for inducing decision rules based on rough set theory and the dominance relationship is presented. In some extent, this algorithm can deal with decision-making problem in which the attribute values are interval grey numbers and some of them are null values. Contrasted with classical model of cluster decision-making, the algorithm has an advantage of flexibility and compatibility to new information. 展开更多
关键词 grey system theory rough set incidence cluster interval grey number entropy null value
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Effects of Limestone Powder on Rheological Properties of Cement - Fly Ash Mortar
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作者 XIE Youjun CHEN Xiaobo +2 位作者 MA Kunlin FENG Jin ZHAN Fang 《International English Education Research》 2015年第12期4-8,共5页
This article studies the effects of limestone powder on rheological properties of cement - fly ash mortar with RHEOLAB QC type rotation viscometer. The Bingham fluid model is introduced to fit the yielding stress and ... This article studies the effects of limestone powder on rheological properties of cement - fly ash mortar with RHEOLAB QC type rotation viscometer. The Bingham fluid model is introduced to fit the yielding stress and plastic viscosity of the mortar. The POWER LAW fluid model is introduced to fit the rheological index of the mortar. The results show that, adding limestone powder and fly ash to the cement mortar significantly decreases the yield stress of the mortar, changes the plastic viscosity of the mortar, increases the rheological index, decreases the degree of shear thinning of the mortar, and thereby improves the mortar' s workability. In the case of cement - fly ash mortar, with the increase of limestone powder content, both the yield stress and plastic viscosity of the mortar increase. When the limestone powder content is not higher than 14%, the increase of yield stress is not significant. When the limestone powder content is lower than 8%, the increase of plastic viscosity is not significant. When the content of limestone powder is higher than 22%, the rheological index of the mortar decreases and the degree of shear thinning increases. The effects of limestone powder' s packing density, shape and size, specific surface area, and fluid volume, are found to be the four major factors responsible for the changes ofrheological properties of the mortar. 展开更多
关键词 cement mortar rheological properties limestone powder fly ash MECHANISM
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