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The Arithmetic Mean Standard deviation Distribution: A Geometrical Framework

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Applied Mathematics 2013年第11期4卷 1-10页

作者： R. Caimmi Physics and Astronomy Department Padua University Padova Italy

The current attempt is aimed to outline the geometrical framework of a well known statistical problem, concerning the explicit expression of the arithmetic mean standard deviation distribution. To this respect, after a short exposition, three steps are performed as 1) formulation of the arithmetic mean standard deviation, , as a function of the errors, , which, by themselves, are statistically independent;2) formulation of the arithmetic mean standard deviation distribution, , as a function of the errors,;3) formulation of the arithmetic mean standard deviation distribution, , as a function of the arithmetic mean standard deviation, , and the arithmetic mean rms error, . The integration domain can be expressed in canonical form after a change of reference frame in the n-space, which is recognized as an infinitely thin n-cylindrical corona where the symmetry axis coincides with a coordinate axis. Finally, the solution is presented and a number of (well known) related parameters are inferred for sake of completeness.

关键词： Standard deviation n-Spaces Direction Cosines Quadrics

Improved Image Contrast Enhancement Based on Local Standard deviation and Compared with Other Algorithms

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Chinese Journal of Biomedical Engineering(English Edition) 2002年第2期11卷 89-96页

作者： ZHANG Feng, JIANG Yi feng, CHEN Zhen cheng, LIN Gang, ZHANG Deng fu, JIANG Da zong Institute of Biomedical Engineering, Xian Jiaotong University,Xian 710049, Shaanxi, China

An adaptive contrast enhancement (ACE) algorithm is presented in this paper, in which the contrast gain is determined by mapping the local standard deviation (LSD) histogram of an image to a Gaussian distribution function. The contrast gain is nonlinearly adjusted to avoid noise overenhancement and ringing artifacts while improving the detail contrast with less computational burden. The effectiveness of our method is demonstrated with radiological images and compared with other algorithms.

关键词： adaptive contrast enhancement local standard deviation (LSD) radiography.

The Weighted Mean Standard deviation Distribution: A Geometrical Framework

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Applied Mathematics 2015年第3期6卷 520-546页

作者： R. Caimmi Physics and Astronomy Department Padua University Padova Italy

The current attempt is aimed to extend previous results, concerning the explicit expression of the arithmetic mean standard deviation distribution, to the general case of the weighted mean standard deviation distribution. To this respect, the integration domain is expressed in canonical form after a change of reference frame in the n-space, which is recognized as an infinitely thin n-cylindrical corona where the axis coincides with a coordinate axis and the orthogonal section is an infinitely thin, homotetic (n-1)-elliptical corona. The semiaxes are formulated in two different ways, namely in terms of (1) eigenvalues, via the eigenvalue equation, and (2) leading principal minors of the matrix of a quadratic form, via the Jacobi formulae. The distribution and related parameters have the same formal expression with respect to their counterparts in the special case where the weighted mean coincides with the arithmetic mean. The reduction of some results to ordinary geometry is also considered.

关键词： Standard deviation n-Spaces Direction Cosines Quadratic Forms Matrix Theory

CALCULATION OF BASIC ENVIRONMENTAL GEOSTROPHIC FLOW AND STATISTICAL STUDY ON TC TRACK AND ITS deviation

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Journal of Tropical Meteorology 2001年第2期7卷 209-217页

作者：高拴柱 National Meteorological Center

Using the T63L16 analysis data with the resolution of 1.875╳1.875 degree of latitude and lon-gitude obtained from National Meteorological Center (NMC) and the real central position information of tropi-cal cyclone (referred to as TC hereafter) numbered by NMC, the basic environmental geostrophic flow at 126 time levels of 25 TCs in 1996 are calculated. The vertical distribution features of the flows are analyzed. Be-sides, the deviation of real TC tracks from the flows (referred as steering deviation hereafter, namely, the de-viation between the real central position of TC and the position calculated according to the steering flow) is also investigated. The result shows that the steering deviation would be different if the domain used to calculate the steering flow is different. The present paper obtains the optimum domain size to calculate the steering flow. It is found that the steering deviation is related to the velocity of steering flow and the initial latitude and intensity of TC itself, and that TC motion has relationship with the vertical shear structure of environmental geostrophic flow. The result also shows that the optimum steering flow is the deep-layer averaged basic flow from 1000 hPa to 200 hPa. Having the knowledge of these principle and features would help make accurate forecast of TC motion.

关键词： environmental geostrophic basic flow steering deviation TC motion

Investor Heterogeneity and Stock Price deviation--Evidence from China's A Stock Market

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经济管理学刊（中英文版） 2018年第2期7卷 107-117页

作者： Meng Zhao SHU-UTS SILC Business School Shanghai University201800China

Investors in the stock market of China mainly make profits from bid-offer spread.This characteristic provides fertile ground for the sharp fluctuation of the stock price.Since the opening of stock market of Shanghai and Shenzhen in 1990,the stock market of China has undergone short-term stock price rise and fall over and over again.Thus it implies that the stock price of China generally deviates from stock intrinsic value.Different from the stock market in most developed countries,the stock market of China primarily dominated by individual investors is more vulnerable to sharp stock price rise and fall.According to different means of investment subjects,this paper divides investors into individual investors and institutional investors,takes in-depth data inspection and regression analysis to observe the correlation between stock price deviation and heterogeneous investors during a relatively stable time frame of domestic stock price deviation degree and explores the fluctuation of heterogeneous investors'holding quantity of heterogeneous stocks in the study on the changes of stock price deviation degree.As indicated by research results,both individual investors and institutional investors have made corresponding investment adjustment in condition when stock price deviates from intrinsic values.However,institutional investors tend to be more rational than individual investor.

关键词： Stock Price deviation Institutional Investor Individual Investor

The Principle and Practice of the deviation of Power Frequency Component Relay on High Voltage Transmission Line

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Electricity 1998年第4期 19-24页

作者： Shen Guorong (Professor and Senior Engineer of NARI)

The research and development of ultra high speed protective relay of transmission line has got great interest and attention of protective relay engineer over the world. Several versions and schemes of ultra high speed relay have been studied and designed in recent twenty years. But only a few of them have got actual apiication in the power system. The relay based on the deviation of power frequency component (DPFC) can get very high reliability with ultra high speed so it has got wide application in Chinese power system. Thousands relay sets have been applied and its operation experience verifies their excellent performance. This paper summarizes the course of the development of the uItra high speed protective relay and compares the merits and defects of the main schemes which have been developed. The principle and successful pratice of the ultra high speed protection based on DPFC reIay are introduced.

关键词： ultra high speed protective relay deviation of power frequency component

Implementing deviation and effects of disaster-induced immigration policy:A case study of southern Shaanxi area

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Ecological Economy 2015年第4期8卷 355-367页

作者： HE De-gui DANG Guo-ying ZHANG Zhao-qing Research Center for Rural Society Northwest A&F University Rural Development Institute Chinese Academy of Social Sciences School of Television Faculty of Journalism and CommunicationCommunication University of China

Immigration issue is one of the major problems in China today.The implementation of disasterinduced immigration policy is a significant contributor to effectively promote targeted measures of helping people in contiguous poor areas with particular difficulties to be out of poverty.Empirical investigation has been conducted to get a systematic grasp of the implementation deviation of massive disaster-induced immigration phenomenon in southern Shaanxi area.According to the survey,phenomenon of "immigrate the rich,while abandoning the poor,more houses with fewer immigrants,four moves and four drops,poor spot choosing and relaxed project management" demands improvement of execution ability.The implementation of such public policy has a large space to improve.Enough attention should be paid to the negative impact of such deviation,and only in this way can we live up to the desired objectives.

关键词： immigration relocation disaster-induced immigration implementation deviation effect

T Wave Amplitude deviation as a Participation Marker of Glycolysis in Myocardial Repolarization

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World Journal of Cardiovascular Diseases 2019年第5期9卷 343-353页

作者： Mikhail U. Alekseev Aleksandr M. Alekseev Juventa Diagnostic Center Saint Petersburg Russia Tozka Diagnostics LLC Moscow Russia

Glucose metabolism is essential for heart physiology, especially in ischemic conditions. Anaerobic glycolysis participates along with aerobic fatty acid oxidation in generating energy supply, and the balance is shifted towards fatty acids. In the case of aerobic path restriction due to coronary artery disease (CAD), this ratio changes. The aim of the present research was to discover the aspects of glycolysis in cardiac electrophysiology.?We utilized the normalized (by average value) T wave amplitude deviation values, named the G criterion,?from high-resolution, 12-channel, 120-seconds-long electrocardiograms,?which were obtained using DACG technology. The calculated G criterion allows a quantitative assessment of the ischemic process and corresponds to the functional class (FC) according to the Canadian cardiovascular classification. We examined 22 healthy people and 79 proven CAD patients: 24 II FC, 40 III FC and 15 IV FC by original ECG and fasting blood sugar tests. A strong correlation was found between the average G criterion from all 12 channels and the level of fasting blood sugar (r = +0.88). In the control group, blood sugar levels were 91 ± 6.5 mg/dl, II FC 103 ± 14.8 mg/dl (p < 0.01), III FC 113 ± 23.4 mg/dl (p < 0.001), and IV FC 152 ± 42.4 (p < 0.001). Moreover, the correlation factor (average G criterion and blood sugar) was strong and positive in each group: control +0.72, II FC +0.83, III FC +0.76, and IV FC +0.89. For the first time, heart electrical activity from the ECG curve was associated with high glucose level as one of the main CAD risk factors. The presence of such dependence of increased blood sugar level from the severity of the ischemic process in the myocardium indicates that hyperglycemic reaction is adaptive and can accelerate the anaerobic glycolysis for energy demand compensation in heart muscle.

关键词： Electrocardiogram T Wave deviation Blood Sugar Hyperglycemia Glycolysis

Convolutional Noise Analysis via Large deviation Technique

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Journal of Signal and Information Processing 2015年第4期6卷 259-265页

作者： Monika Pinchas Department of Electrical and Electronic Engineering Ariel University Ariel Israel

Due to non-ideal coefficients of the adaptive equalizer used in the system, a convolutional noise arises at the output of the deconvolutional process in addition to the source input. A higher convolutional noise may make the recovering process of the source signal more difficult or in other cases even impossible. In this paper we deal with the fluctuations of the arithmetic average (sample mean) of the real part of consecutive convolutional noises which deviate from the mean of order higher than the typical fluctuations. Typical fluctuations are those fluctuations that fluctuate near the mean, while the other fluctuations that deviate from the mean of order higher than the typical ones are considered as rare events. Via the large deviation theory, we obtain a closed-form approximated expression for the amount of deviation from the mean of those fluctuations considered as rare events as a function of the system’s parameters (step-size parameter, equalizer’s tap length, SNR, input signal statistics, characteristics of the chosen equalizer and channel power), for a pre-given probability that these events may occur.

关键词： Large deviation Theory Blind Equalization Blind Deconvolution