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101.
为了解决传统温湿度测量系统存在的标定和校准过程复杂而引起的精度不高的问题,文中介绍了一种新型的温湿度测量系统。该系统由瑞士SENSIR ION公司新生产的SHT11数字式温湿度传感器和日本NEC公司生产的78F9177Y单片机为核心组成,具有电路简单、免标定、精度高和可靠性好等优点。  相似文献   
102.
Guangxing Lin  Zuntao Fu 《Physica A》2007,383(2):585-594
Long-range correlations of daily relative humidity anomaly records from 191 weather stations over China during 1951-2000 are analyzed by means of fluctuation analysis (FA) and detrended fluctuation analysis (DFA). The information about trends in the relative humidity records can be obtained by comparing the FA curve with DFA curves. The daily relative humidity fluctuations are found to be power-law correlated and their average scaling exponent is higher than that of the temperature fluctuations, indicating that the relative humidity fluctuations take different statistical behavior from other meteorological quantities and there exists a stronger persistence in the relative humidity fluctuations. Furthermore, it is also found that these power-law scaling properties vary from station to station and show both spatial and temporal diversities, which may be explained by a proposed mechanism.  相似文献   
103.
Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four Chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.  相似文献   
104.
在解析几何中有二次曲线与直线位置关系的讨论、二次曲面与直线位置关系的讨论,而二次曲面与平面相关位置关系的探讨较少.本文给出二次曲面a11x2+a22y2+a33z2+2a12xy+2a13xz+2a23yz+2a14x+2a24y+2a34z+a44=0(1)和平面Ax+By+Cz+D=0(2)的相对位置的判别式Δ=a11a12a13a14Aa21a22a23a24Ba31a32a33a34Ca41a42a43a44DA B C D0(aij=aji).(3)并证明了:若Δ>0,则二次曲面(1)与平面(2)相交;若Δ=0,则(1)和(2)相切;若Δ<0,则(1)和(2)相离.  相似文献   
105.
定义了一般线性模型参数的最小二乘估计(LS估计)与BLU估计的一种新的相对效率,给出了当设计矩阵满秩,协方差阵非负定时这种相对效率的下界,最后讨论了其与广义相关系数(zρ3)之间的关系.  相似文献   
106.
李尧龙 《数学季刊》2008,23(1):8-15
In this paper,two concepts of relative compactness-the relative strong fuzzy compactness and the relative ultra-fuzzy compactness are defined in L-topological spaces for an arbitrary L-set.Properties of relative strong fuzzy sets and relative ultra-fuzzy compact sets are studied in detail and some characteristic theorems are given.Some examples are illustrated.  相似文献   
107.
108.
For cryptographic purposes, we want to find functions with both low differential uniformity and dissimilarity to all linear functions and to know when such functions are essentially different. For vectorial Boolean functions, extended affine equivalence and the coarser Carlet–Charpin–Zinoviev (CCZ) equivalence are both used to distinguish between nonlinear functions. It remains hard to tell when CCZ equivalent functions are EA‐inequivalent. This paper presents a framework for solving this problem in full generality, for functions between arbitrary finite groups. This common framework is based on relative difference sets (RDSs). The CCZ and EA equivalence classes of perfect nonlinear (PN) functions are each derived, by quite different processes, from equivalence classes of splitting semiregular RDSs. By generalizing these processes, we obtain a much strengthened formula for all the graph equivalences which define the EA equivalence class of a given function, amongst those which define its CCZ equivalence class. © 2010 Wiley Periodicals, Inc. J Combin Designs 18: 260–273, 2010  相似文献   
109.
本文给出一种双扰动随机化回答模型.理论上扰动变量的引入会降低随机化调查的效率,本文使用两个设计参数设计了一种合理的双扰动变量随机化问答技术,在不降低装置对个体保护度的情况下,得出的结论表明,使用两个扰动变量可以提高调查装置的效率.通过数值模拟验证了本文模型的效率优于Bar-Lev,Bobovitch和Boukai 2004年单扰动回答模型的效率.  相似文献   
110.
A scheme for creating an arbitrary coherent superposition of two atomic states in serial multi-A-type system is proposed.This technique with the application of a control field is based on the existence of two degenerate dark states and their interaction.The mixing of the dark states can be controlled by changing the relative delay time of the control pulse.One can get any desired superposition by changing the delay time of the control pulse.  相似文献   
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