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1.
利用C*-代数到B(H)中的等距*-表示,研究C*-代数中的Bohr不等式,得到了4个推广的Bohr不等式成立的一些充分必要条件1.主要结论如下:设p,q∈R~+,且满足1/p+1/q=1,则A,B∈S(S为有单位元的C*-代数),|A-B|~2+|(1-p)A-B|~2≤p|A|~2+q|B|~2成立当且仅当p≤2;设α,β,u,v∈R,p,q∈R~+,则|αA+βB|~2+|uA+vB|~2≤p|A|~2+q|B|~2成立当且仅当p≥α~2+u~2,q≥β~2+v~2且(p-(α~2+u~2))(q-(β~2+v~2))≥(αβ+uv)~2;设a,b∈R~+,c∈C,则A,B∈S,a|A|~2+b|B|~2+cA*B+cB*A≥0成立当且仅当ab≥|c|2;设α,β∈R,x,y是正数,则A,B∈S,|αA+βB|~2≤x|A|~2+y|B|~2成立,当且仅当x≥α~2,y≥β~2且(x-α~2)(y-β)≥α~2β~2.  相似文献   

2.
设A=(aij)∈Cn×n,若α∈(0,1),i,j∈N,i≠j,有|aii | |ajj|≥Rαi (A)Rαj(A)S1-αi(A)S1 -αj(A)成立,则称A为α-双链对角占优矩阵.为给出H-矩阵的判别条件,首先推广α-双链对角占优矩阵到广义α-双链对角占优矩阵,然后得到了判别广义α-双链对角占优矩阵的一个充分条件,改进和推广了已有的结论,进一步丰富了广义α-双链对角占优矩阵和非奇H-矩阵的理论.  相似文献   

3.
B(H)上的零点广义*-Lie可导映射   总被引:1,自引:1,他引:0  
设(A)是一个代数,如果(A)a,b∈A且[aa*,b]=0,都有[φ(a)φ(a)*,b]+[aa*,φ(b)]-aφ(I)b+bφ(I)a=0,则称φ是(A)上的零点广义*-Lie可导映射.证明了B(H)上的零点广义*-Lie可导映射是广义内导子.  相似文献   

4.
设A=(aij)∈Cn×n,若α∈(0,1),使i∈N+,有|aii|≥Riα(A)S1i-α(A)成立,则称A为Ostrowski对角占优矩阵;推广Ostrowski对角占优矩阵的概念到广义Ostrowski对角占优矩阵;得到了判别非奇异H-矩阵的一个判定方法.进一步丰富和完善了Ostrowski对角占优矩阵和非奇异H-矩阵的理论.  相似文献   

5.
因子von Neumann代数上的正交可导映射   总被引:2,自引:2,他引:0  
设M是作用在维数大于2的复可分Hilbert空间(A)上的因子von Neumann代数如果(V)A,B∈M且A*B =AB*=0,有φ(A)*B+A*φ(B)=φ(A)B*+Aφ(B)*=0,则称φ是M上的正交可导线性映射.证明了M上有界的正交可导线性映射是广义内导子.  相似文献   

6.
运用算子论方法,研究了因子von Neumann代数上的非线性满射强保*-交换映射.证明了当且仅当λ∈C且λλ=1和函数h:M→C,使得A∈M,有(A)=λA+h(A)I.得到了因子von Neumann代数上的非线性满射强保*-交换映射是数乘算子和常数之和.  相似文献   

7.
设M2(R)是二阶实矩阵代数,A,B∈M2(R),定义新积[A B]T=AB-BAT,其中AT表示矩阵A的转置.φ是M2(R)→M2(R)上的非线性齐次双射且满足([A B]T)=[φ(A)φ(B)]T,则存在正交矩阵Q∈M2(R),对任意矩阵A∈M2(R),都有φ(A)=QAQT.  相似文献   

8.
设f:[0,1]×R→R的连续函数.设η∈[0,1],α,β∈R且α≠1,β≠1为给定常数.在非线性项f满足某种增长条件的前提下考虑非线性二阶三点边值问题u"+f(t,u)=0,0相似文献   

9.
设p和q是两个奇素数,且p相似文献   

10.
设F为元素个数大于3的域,M2(F)为F上的2×2矩阵代数,T2(F)≡{T| T3=T,T∈M2(F)}.所有满足φ:M2(F)→M2(F),A+λB∈T2(F)=>φ(A)+λφ(B)∈T2(F),∨A,B∈T2(F),λ∈F的单映射构成的集合用Φ表示.利用保立方幂等映射和原象之间的关系刻画了集合Φ中元素的形式.  相似文献   

11.
应用数字色彩传感器和微控制器设计一种油脂颜色检测实验装置,检测输出油脂颜色的三基色(红、绿、蓝)信号,即RGB值。为避免RGB模型的缺点,将油脂颜色检测值转换到与设备无关的CIE表色系统,完成由RGB值向CIE–XYZ值、CIE–L*a*b*值的转换,并采用颜色检测组件HDJD–JD02对颜色模型转化公式进行校正。结果表明,油脂颜色可以基于光学和色度学理论进行描述,并可以转换到其它颜色空间。  相似文献   

12.
目的分析不同水质对茶类品质的影响,为泡茶用水的选择提供理论依据。方法采用电极法、电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)分析水质特性,采用感官审评和色差计法分析茶汤色香味品质和L~*a~*b~*色泽。结果纯净水p H 6.07,电导率1.06μs/cm,含微量金属离子,泡出的茶汤明亮,香味纯正;山泉水p H 7.42,电导率8.89μs/cm,含丰富的K~+、Na~+、Mg~(2+)和Ca~(2+),泡红茶、乌龙茶和白茶色香味品质最佳,泡绿茶滋味较涩,香气闷;矿泉水p H 6.42,微酸性,电导率17.86μs/cm,含氟化物和Na~+、K~+、Mg~(2+)、Al~(3+)、Fe~(3+)和Ca~(2+),泡出乌龙茶色香味品质最佳;自来水p H 7.63,电导率37.1μs/cm,含氟化物和Na~+、K~+、Mg~(2+)、Zn~(2+)、Fe~(3+)和Ca~(2+),冲泡各种茶色香味最差。结论纯净水是泡茶的最佳水源,山泉水和矿泉水更适宜泡发酵茶类,自来水对茶汤品质影响最大。  相似文献   

13.
Three hundred twenty honey samples were collected from Ethiopia, and categorized into nine monofloral honeys using melissopalynology. Theses monofloral honeys were investigated for their sugar profile, physicochemical properties, and quality of honeys. Sugars (fructose, glucose, sucrose, maltose, turanose, and isomaltose) were identified using high-performance liquid chromatography and physicochemical properties (moisture, water activity, pH, acidity, ash, minerals, conductivity, colour) using the Harmonized Method of the International Honey Commission. Moisture and water activity showed a strong regression coefficient (r2 = 0.92). Moisture content alone did not sufficiently describe the quality of honey during storage and processing.  相似文献   

14.
抗氧化剂对冷冻牛肉护色效果的应用研究   总被引:1,自引:0,他引:1  
研究了四种抗氧化剂对冷冻牛肉的护色效果。采用Box-Behnken响应面设计法进行实验对四种抗氧化剂的用量范围进行了优化设计,并采用Design-Expert7.1.6软件进行了数据拟合。实验优化后的△a*值为0.1632,与△a*的预测值0.1524基本吻合,模型极其显著(P<0.01),方程拟合度高(R2=0.9567)。经验证后,模型选用合理有效。确定了四种抗氧化剂的最佳配比:即烟酰胺0.22%、D-异抗坏血酸钠0.019%、植酸钠0.033%、茶多酚0.027%。四种抗氧化剂对冷冻牛肉护色效果影响大小的排列顺序依次为:茶多酚>植酸钠>烟酰胺>D-异抗坏血酸钠。结合CIE L*a*b*表色系统进行视觉分析,△E*ab=1.496,与观察感觉中感觉到的色差程度为"稍有差异",此结论与感官评价"颜色较好、光泽微暗"的结论基本吻合。证明了该实验得出的最佳配比对冷冻牛肉的护色效果明显。  相似文献   

15.
The objective of this study was to evaluate the use of digital images (DI) to estimate CIE L*a*b*, hue angle and chroma of beef, as compared to a colorimeter (CM). Loin samples from 21 steers finished with high-grain diets were displayed under retail-simulated conditions. Color readings were obtained from 63 cores covering the full spectrum of discoloration in beef. CIE L*, a*, and b* were measured with a surface-reflectance CM. Red, green and blue (RGB) values were obtained from DI and sequentially transformed to XYZ and CIE L*a*b* color space. Hue angle and chroma were calculated from a* and b* values. Regressions of CM on DI for a*, hue angle and chroma had R2 values of 0.93 and above. Average color difference () between the predicted and the actual CM L*, a*, and b* values for 13 samples that were not included in the regressions was 1.57, below reported thresholds of detection for 50% of observers. Color readings from DI could be used to accurately predict color coordinates measured by CM, especially a*, hue angle and chroma. Use of digital imaging could become a practical tool to detect changes in beef color and other muscle foods.  相似文献   

16.
一类特殊的归纳~*-半环   总被引:1,自引:1,他引:0  
研究了一类特殊的归纳*-半环.通过给出一种具体的星号运算,并从这一具体的运算出发,构造了一类特殊的归纳*-半环.得到了一类特殊的归纳*-半环,并得到了一些性质,给出了一些应用.能够在同一代数结构上通过定义不同的星号运算得到相应的归纳*-半环,如果能够恰当的定义星号运算,将会使这一代数结构变得更加清晰.  相似文献   

17.
Fractal dimension (FD) estimation has become most popular in the field of image analysis and applications; especially estimating the roughness and smoothness of complex objects. In this present investigation, we are considering three most popular methods in the controlled images acquisition experimental setup for eight colored fabrics of the same texture, material property, and illumination. The concept of previous work and the results obtained by this ground truth experiment were discussed to indicate whether FD might be a worth useful metric for the study of color images with self-similarity, such as textures! Interestingly, we found ambiguous FD results here and tried to explain such phenomenon in relation to the development of CIE-based human perception model as texture perception are well associated with the viewing parameters and observer that perceives the image in terms of spatial distribution of color intensity.  相似文献   

18.
A detection algorithm based on CIE L*a*b* color space is proposed to detect various colorful fabric defects more accurately and avoid the error detection resulted from losing image information of graying. CIE L*a*b* color space is transformed from XYZ space via nonlinear transformation of RGB space. First, three features including the brightness characteristics L*, color information of a* and b* which are used to form 2-D Gabor filter in a complex number can be acquired. Genetic algorithm with the objective function in a form of energy is adopted to select optimal Gabor filter parameters. Second, filter built by flawless image is used to filter the corresponding drawbacks of image. Third, ultimate results are obtained through sliding threshold segmentation method and properly de-noising. The experiment success rate is 95.83%, which indicate that this method can detect diversiform colorful fabric defect accurately.  相似文献   

19.
部分归纳~*-半环   总被引:1,自引:1,他引:0  
将部分Conway半环进行推广,得到了更一般的的Kleene定理.通过引入部分(弱)归纳*-半环的定义,研究了对这两类半环性质,给出了部分(弱)归纳*-半环与部分Conway半环的关系,得到了部分(弱)归纳*-半环上的Kleene定理.所得结果推广(弱)归纳*-半环上的Kleene定理,丰富了半环理论.  相似文献   

20.
The changes in the physico-chemical, microbiological, textural and sensory attributes of foal salchichón were followed during ripening. Foal salchichón samples were taken at 0 days (mix before stuffing), and after 7, 14, 21, 28, 35, 42 and 49 days of ripening. The final aw was 0.82, whereas pH values stayed around their initial values. TBAR'S values increased significantly (P < 0.001) during processing, from 0.44 to 2.26 mg/kg of sausage. Ripening time also affected the lightness (L*), redness (a*) and yellowness (b*) (P < 0.001). Hardness, gumminess and chewiness increased (P < 0.001) from 0.96, 0.6 and 0.47 to 46.92 kg/cm2, 21.34 kg/cm2 and 15.14 kg, respectively during processing, whereas cohesiveness and springiness values decreased during ripening. Lactic acid bacteria increased slowly in number and a large increase of Micrococcaceae was noticed. Regarding sensorial characteristics, foal salchichón samples showed high values for intensity of flavour (7.22 ± 0.44), hardness (7.33 ± 0.71) and dryness (6.67 ± 0.71) and low scores for acid taste (1.67 ± 0.71) and saltiness (3.11 ± 0.6).  相似文献   

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