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在单片机系统中利用图素数值特征的二值图象处理算法研究 被引量:2
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作者 戴永 《计算机工程与应用》 CSCD 北大核心 2003年第1期109-111,114,共4页
根据二值图素8-邻接点结构变化规律及MCS-51系列单片机存储系统工作特点提出利用二值图素数值特征进行图像处理的算法,并将算法软件利用局部图域递归处理方法成功移植到MCS-51系列单片机二值图像处理系统,形成适用MCS-51系列单片机存储... 根据二值图素8-邻接点结构变化规律及MCS-51系列单片机存储系统工作特点提出利用二值图素数值特征进行图像处理的算法,并将算法软件利用局部图域递归处理方法成功移植到MCS-51系列单片机二值图像处理系统,形成适用MCS-51系列单片机存储系统的二值图像处理算法。该算法也适用于其他系列单片机实现二值图像处理。 展开更多
关键词 单片机系统 素数特征 二值图象处理算法 图象分析
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关于Herstein定理的逆问题研究
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作者 胡付高 黄玉昌 《孝感学院学报》 2002年第6期42-43,共2页
设R是一个环,如果存在n>1使f:x→xn为R的一个环同态,则映射f:R→R称为一个幂自同态。本文将完全刻划出无零因子环的所有幂自同态。
关键词 无零因子环 幂自同态 素数特征 交换环 逆问题 Jacobson定理 Herstein定理
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Emission Characteristics of Soil Nitrous Oxide from Typical Greenhouse Vegetable Fields in North China
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作者 徐钰 刘兆辉 +5 位作者 魏建林 石璟 谭德水 王梅 李国生 江丽华 《Agricultural Science & Technology》 CAS 2017年第3期438-442,共5页
To make clear the emission characteristics of soil N20 from typical green- house vegetable fields in North China, an experiment was conducted in greenhouse tomato field in Shouguang city, Shandong province, China's ... To make clear the emission characteristics of soil N20 from typical green- house vegetable fields in North China, an experiment was conducted in greenhouse tomato field in Shouguang city, Shandong province, China's "Home of Vegetables". The N2O fluxes were observed in four experimental treatments, as follows: none N fertilizer (CK), single organic fertilizer (OM), conventional fertilization (FP) and opti- mized and reduced nitrogen fertilization (OPT), by a close chamber-gas chromato- graph method. The effects of different fertilization treatments on N2O emission and tomato yield were analyzed. The results showed that following the fertilization and ir- rigation, the pulsed emissions of N2O were measured. The N2O emission peak ap- peared after basal fertilizer application and irrigation and could be maintained for about 20 days. While the N2O emission peak caused by topdressing was smaller and last only 3-5 days. The statistical analysis showed that the N2O fluxes were affected by air temperature, soil temperature and WFPS at soil depth of 3 cm. The total contents of soil N2O fluxes had significant differences among experimental groups. The total content orderly was FP of 14. 77 kg/hm^2, OPT of 9. 73 kg/hm^2, OM of 6.84 kg/hm^2 and CK of 2.37 kg/hm^2. The N~:~ emission coefficient ranged from 0.83%-1.10%,which was close to or more than the recommended value (1.0%) by IPCC. Compared with the FP treatment, the tomato yield in OPT treatment, whose application rate of chemical N fertilizer decreased by about 60%, increased by 2.2%. Under the current management measures, the reasonable reduction on ap- plicaUon rate of organic manure and chemical nitrogen fertilizer could effectively re- duce the N=O emissions in greenhouse vegetable fields. 展开更多
关键词 Greenhouse vegetable field N2O emission characteristic Influencingfactor Emission coefficient Tomato yield
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Analysis of Physical and Chemical Characteristics and Influence Factors of UCG 被引量:1
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作者 杨兰和 白海波 《Journal of China University of Mining and Technology》 2001年第1期24-28,共5页
Based on the UCG(underground coal gasification) theory, the “three zones” which are oxidization zone, reduction zone, and drying zone, were divided; physical and chemical properties of each zone were analyzed. Facto... Based on the UCG(underground coal gasification) theory, the “three zones” which are oxidization zone, reduction zone, and drying zone, were divided; physical and chemical properties of each zone were analyzed. Factors, such as temperature, rate of water pouring, quantity of air blast, thickness of coal seam, and the operation pressure were discussed. Among the influencing factors, the temperature is the most important one. 展开更多
关键词 underground coal gasification three zones chemical reaction
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Steganalysis of LSB Matching Using Characteristic Function Moment of Pixel Differences 被引量:1
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作者 Xianyi Chen Guangyong Gao +1 位作者 Dandan Liu Zhihua Xia 《China Communications》 SCIE CSCD 2016年第7期66-73,共8页
Nowadays,many steganographic tools have been developed,and secret messages can be imperceptibly transmitted through public networks.This paper concentrates on steganalysis against spatial least significant bit(LSB) ma... Nowadays,many steganographic tools have been developed,and secret messages can be imperceptibly transmitted through public networks.This paper concentrates on steganalysis against spatial least significant bit(LSB) matching,which is the prototype of many advanced information hiding methods.Many existing algorithms deal with steganalysis problems by using the dependencies between adjacent pixels.From another aspect,this paper calculates the differences among pixel pairs and proves that the histogram of difference values will be smoothed by stego noises.We calculate the difference histogram characteristic function(DHCF) and deduce that the moment of DHCFs(DHCFM) will be diminished after stego bits are hidden in the image.Accordingly,we compute the DHCFMs as the discriminative features.We calibrate the features by decreasing the influence of image content on them and train support vector machine classifiers based on the calibrated features.Experimental results demonstrate that the DHCFMs calculated with nonadjacent pixels are helpful to detect stego messages hidden by LSB matching. 展开更多
关键词 information hiding steganalysis pixel differences nonadjacent pixels SVM
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Research of mathematic culture and quality of mathematics education
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作者 LiqinTian 《International Journal of Technology Management》 2014年第6期38-40,共3页
In the basic concepts of mathematic culture, mathematics was given a broad meaning. Mathematics is not only a scientific language, a system of knowledge, but also a way of thinking, a kind of art has aesthetic feature... In the basic concepts of mathematic culture, mathematics was given a broad meaning. Mathematics is not only a scientific language, a system of knowledge, but also a way of thinking, a kind of art has aesthetic features. On this basis, the meaning of mathematical quality should have a new exposition, the essence of mathematical quality is integration of mathematic cultural values, knowledge, abilities, psychological, while the key to the quality of mathematics education is to fully embody the essence of mathematics culture, let the concepts of mathematic cultm'e integrated to the whole process of mathematics education. 展开更多
关键词 mathematic CULTURE quality education
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Moments of L-Functions Attached to the Twist of Modular Form by Dirichlet Characters
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作者 Guanghua JI Haiwei SUN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第2期237-252,共16页
Let f(z) be a holomorphic cusp form of weight κ with respect to the full modular group SL2(Z). Let L(s, f) be the automorphic L-function associated with f(z) and χ be a Dirichlet character modulo q. In this ... Let f(z) be a holomorphic cusp form of weight κ with respect to the full modular group SL2(Z). Let L(s, f) be the automorphic L-function associated with f(z) and χ be a Dirichlet character modulo q. In this paper, the authors prove that unconditionally for k =1/n with n ∈ N,Mk(q,f)=∑χ(mod q)χ≠χ0|L(1/2,f χ)|^2k〈〈 kФ(q)(log q)^k^2, and the result also holds for any real number 0 〈 k 〈 1 under the GRH for L(s, f χ).The authors also prove that under the GRH for L(s, f χ),for any real number k 〉 0 and any large prime q. 展开更多
关键词 MOMENTS Automorphic L-functions Convexity theorem
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A CRITERION FOR TESTING WHETHER A DIFFERENCE IDEAL IS PRIME
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作者 Chunming YUAN Xiao-Shan GAO Key Laboratory of Mathematics Mechanization,Institute of Systems Science Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China. 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2009年第4期627-635,共9页
This paper presents a criterion for testing the irreducibility of a polynomial over an algebraicextension field.Using this criterion and the characteristic set method,the authors give a criterion fortesting whether ce... This paper presents a criterion for testing the irreducibility of a polynomial over an algebraicextension field.Using this criterion and the characteristic set method,the authors give a criterion fortesting whether certain difference ascending chains are strong irreducible,and as a consequence,whetherthe saturation ideals of these ascending chains are prime ideals. 展开更多
关键词 Characteristic set difference prime ideal IRREDUCIBILITY strong irreducibility.
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