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statistical parameters derived from ozonesonde data of importance for passive remote sensing observations of ozone

INTERNATIONAL JOURNAL OF REMOTE SENSING 2002年第22期23卷 4945-4963页

作者： Eriksson, P Chen, D Chalmers Univ Technol Dept Radio & Space Sci SE-41296 Gothenburg Sweden Univ Gothenburg Dept Earth Sci SE-40530 Gothenburg Sweden

A reliable climatology of vertical ozone and temperature variability is essential for our understanding of climate, modelling work and profile retrieval from passive remote sensing observations. This paper describes a statistical analysis of ozonesonde data collected from 1970 to 1996 at 17 stations in the northern hemisphere. The aim of the analysis is to provide a number of parameters describing vertical ozone and temperature variance, justified primarily by the importance of such information for remote sensing applications. Deviations between local means, probability density functions, standard deviations, and correlation between different pressure levels are reported for altitudes below 10hPa and three latitude bands (around 35degreesN, 50degreesN and 75degreesN). The analysis includes also cross-correlation between ozone and temperature. Differences are found between local mean values up to 40% and 15 K for ozone and temperature, respectively. Standard deviations are 10-80% for ozone and 2-15 K for temperature. For ozone the exponential correlation length is normally 2-5 km, while for temperature the vertical correlation is more inhomogenous. The implications for inversion of remote sensing measurements are discussed.

关键词： Temperature Profiles Atmosphere passive remote sensing atmosphere Temperature Vital Signs ozone remote sensing measurements Deviation Ozonesondes statistical parameters gag press straightening

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statistical parameters of In-A-Lane Multiple Truck Presence and a New Procedure to Analyze the Lifetime of Bridges

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STRUCTURAL ENGINEERING INTERNATIONAL 2016年第2期26卷 150-159页

作者： Ghasemi, Seyed Hooman Nowak, Andrzej S. Parastesh, Hossein Islamic Azad Univ Qazvin Branch Dept Civil Engn Qazvin Iran Auburn Univ Dept Civil Engn Auburn AL 36849 USA Univ Sci & Culture Dept Engn Tehran Iran

Design and evaluation of highway bridges requires the assessment of live loads, which can involve a considerable degree of uncertainties. These uncertainties typically refer to the number of vehicles, weight of vehicles, headway distance, type of vehicles, axle spacing, axle load, speed of vehicles and other factors. Therefore, in order to perform a reliability analysis, it is necessary to consider live load as a random variable. Multiple truck presence (MTP) and headway distance also are two random variables that should be deliberated for the assessment of live load. The basic goal of this study is to update the statistical parameters of in-a-lane MTP, using the recent available weigh-in-motion (WIM) data, and then delineate the relationship between the bridge lengths and the influence of MTP events. However, since MTP is a time-dependent variable, the statistical parameters of MTP influences should be determined for the considered lifetime of the bridge. Therefore, the main contribution of this study is to propose a new methodology to calculate the statistical parameters of MTP for different time periods. The dataset for this study includes WIM data from 19 stations throughout the United States, which were collected by the Federal Highway Administration over 5 years, with timestamp accuracy of one-hundredth of a second.

关键词： statistical parameters multiple truck presence headway distance bridges reliability analysis

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statistical parameters-based image enhancement techniques in pure and nanodispersed 6O.O8 liquid crystalline compounds

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PHASE TRANSITIONS 2018年第8期91卷 821-832页

作者： Tripathi, Durga Prasad Pardhasaradhi, P. Madhav, B. T. P. Koneru Lakshmaiah Educ Fdn Antennas & Liquid Crystals Res Ctr Dept ECE Guntur India

Synthesis, characterization and phase-transition studies in pure and 20 mu l citrate-capped Au nanodispersed liquid crystalline (LC) N-(p-n-hexyloxybenzylidene)-p-n-octyloxy aniline, 6O.O8, compounds are carried out using a polarizing microscope attached with hot stage and camera. The polarizing microscopy technique is used to measure the phase-transition temperatures. Differential scanning calorimetry is used to determine the transition temperatures and enthalpy values. By the dispersion of citrate-capped Au nanoparticles into the LC compounds, the nematic transition temperature is decreased. Furthermore, statistical parameters-based image enhancement algorithm is proposed to identify the crystalline phases in the pure and nano-doped LC compound. Empirical result analysis clearly reveals the robustness of this method over existing image enhancement methods.

关键词： Differential scanning calorimetry image enhancement nanodispersion statistical parameters

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statistical parameters of the indicating surface of natural reflectance for biaxial transparent media

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JOURNAL OF MODERN OPTICS 1997年第9期44卷 1661-1670页

作者： Dineiro, JM Alfonso, S Alberdi, C Berrogui, M Departamento de Fisica Universidad Publica de Navarra Campus de Arrosadia s/n Pamplona 31006 Spain

The optical properties are an important characteristic of a mineral. These properties can be studied with a photometer microscope using the indicating surface of natural reflectance (ISRN). Transparent uniaxial media have been studied. Biaxial transparent media, in the same way as uniaxial media, can be analysed by knowing the statistical parameters of the ISRN. To analyse these media, we need the expressions that relate these parameters to the refractive index of the incident medium and to the principal indices of the medium under observation.

关键词： Hyalin Biaxial Optical properties statistical parameters Reflectance complex refractive index

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statistical parameters of Separation Processes

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REFRACTORIES AND INDUSTRIAL CERAMICS 2020年第6期60卷 548-554页

作者： Barsky, E. M. Barsky, M. D. Azrieli Coll Engn Jerusalem Israel Ben Gurion Univ Negev Beer Sheva Israel

The regime of two-phase ascending flow in which the solid phase can move in both directions is called critical. The analysis of such flow from the standpoint of statistical approach made it possible to establish key parameters characterizing such mass transfer process. The chaotizing factor and solid phase mobility are among the energy characteristics of this process. It was shown that two-phase systems, which can exchange energy and particles, evolve towards an equilibrium state with maximal entropy. In this case, the ratio between mobility factors and chaotizing factor in all parts of the system acquires the same value. The analysis of this ratio leads to a universal affinization criterion of separation curves. In this respect, the identity of this criterion for different size grades ensures their equal extractability. A correlation between the key parameters characterizing a two-phase flow as a statistical process has been determined.

关键词： separation statistical parameters chaotizing factor potential extraction entropy cascade separator

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Diffractive optical elements with a double identical microstructure for determination of statistical parameters of random phase objects

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OPTICS AND SPECTROSCOPY 2003年第2期95卷 303-310页

作者： Perepelitsina, OA Ryabukho, VP Gorbatenko, BB Saratov NG Chernyshevskii State Univ Saratov 410026 Russia Russian Acad Sci Inst Problems Fine Mech & Control Saratov 410028 Russia Saratov State Tech Univ Saratov 410054 Russia

Physical processes of interference pattern formation in partially coherent and coherent optical systems containing special diffractive optical elements with a double identical microstructure are studied in the case when a thin scattering object is present in the optical system. Methods for determining the spatial coherence function of the light field, the autocorrelation function of transmission of random phase screens, and the statistical parameters of the screens are considered. (C) 2003 MAIK "Nauka/Interperiodica".

关键词： random phase Optical Systems Identical PARTIAL COHERENCE Physical Processes statistical parameters COHERENT OPTICAL SYSTEMS Autocorrelation function

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Experimental determination of statistical parameters associated with uniaxial compression behaviour of brick masonry

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CURRENT SCIENCE 2015年第11期109卷 2094-2102页

作者： Balasubramanian, S. R. Maheswari, D. Cynthia, A. Rao, K. Balaji Prasad, A. Meher Goswami, R. Sivakumar, P. CSIR Struct Engn Res Ctr Madras 600113 Tamil Nadu India Kumaraguru Coll Technol Dept Civil Engn Coimbatore 641006 Tamil Nadu India VelTech Multi Tech Dr Rangarajan Dr Sakunthala En Dept Civil Engn Madras 600025 Tamil Nadu India Indian Inst Technol Dept Civil Engn Madras 600036 Tamil Nadu India

In view of practical significance of the compression behaviour of brick masonry, this article discusses the evolvement of an experimental programme based on a survey of the literature. Also, it is known that large scatter is expected in the mechanical properties of masonry and studies characterizing these statistical variations are scant in India. Using the evolved experimental programme and results of tests conducted, the statistical parameters, namely mean and coefficient of variation (COV) associated with the uniaxial compression behaviour of typical brick masonry used in South India have been determined in this article. For the masonry considered in this study, the mean values of peak compressive stress, strain corresponding to peak stress and elastic modulus are 2.82 MPa, 0.009 and 0.4 GPa respectively. The corresponding values of COV are 0.15, 0.2 and 0.12 respectively. In addition, a trilinear curve has been suggested as an idealized stress-strain relation for the brick masonry used in South India.

关键词： Clay brick masonry compressive strength elastic modulus uniaxial compression statistical parameters

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Sensitivity of probabilistic fracture mechanics analysis to variations in statistical parameters

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THEORETICAL AND APPLIED FRACTURE MECHANICS 2007年第3期48卷 231-237页

作者： Sprung, I. 415 Erin Rd Stoughton MA 02072 USA

Probability of failure (p(f)) of a structure is usually calculated for a specified set of statistical parameters (mean, standard deviation, and probability distribution) that characterize random variables. This approach may not be efficient in cases where one would like to know the effect of variations in statistical parameters on the probability of failure. A method based on generating and analyzing randomly selected statistical parameters is proposed. The method consists of generating data-bases of mean and coefficient of variation (COV = mean/standard deviation) values of relevant fracture mechanics variables through a random process. The method was applied to surface cracks in a flat wide plate loaded under elastic conditions. Probability of failure was calculated for each database record using the first-order reliability method (FORM). Multiple linear regression analyses of the database records were performed with p(f) as dependent variable and statistical parameters as independent variables. The predicted p(f) values were in very good agreement with the directly calculated p(f) values for the specified variations of statistical parameters (+/- 10%, +/- 15%, and +/- 20%), except those for fracture toughness and tensile stress, where variations should be limited to +/- 10% and +/- 15% ranges. (C) 2007 Elsevier Ltd. All rights reserved.

关键词： Probabilistic fracture mechanics statistical parameters Surface crack Sensitivity

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statistical parameters of the Measured Voltage in the Network 20

Statistical Parameters of the Measured Voltage in the Networ...

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19th International Conference on Electrical Drives and Power Electronics (EDPE) / 9th Joint Slovakian-Croatian Conference

作者： Guzan, Milan Feher, Adam Vince, Tibor Tech Univ Kosice Dept Theoret & Ind Elect Engn Kosice Slovakia

ISBN: (纸本)9781728103891

In the article we present a graphical representation of selected statistical parameters long-time measurement of the voltage in the network. The parameters are calculated from samples of 900 measured values (15-minute measurement interval - one measured value per second), measured by UT 803 multimeter. Changes in statistical parameters will allow to detect the dynamics of connecting/disconnecting electrical appliances, long-term too high or too low voltage, or short-time power failure. The reason for some major parameter changes is revealed by a graphical representation of the time courses of the respective measurement section at that day and hour.

关键词： network voltage statistical parameters multimeter mathematical statistics

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Inspection method for random simulation of runoff sequence based on sample entropy and statistical parameters

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JOURNAL OF HYDROLOGY 2020年第0期581卷 124392-000页

作者： Ma, X. X. Zhu, H. Q. Xiao, Y. Wang, W. S. Wang, H. L. Zhang, J. W. Zhengzhou Univ Sch Water Conservancy & Environm Zhengzhou 450001 Peoples R China Tsinghua Univ State Key Lab Hydrosci & Engn Beijing 100084 Peoples R China

The traditional inspection method of runoff simulation sequences is based on statistical parameters. While the method can reflect the coincidence of statistical parameters of runoff simulation series and observed data at different time intersections, it ignores the characteristics of runoff as time series (e.g., nonlinearity, dissipation and complexity) which might be required in hydrological engineering. By introducing the concept of sample entropy to quantify complexity, we proposed a new method based on sample entropy and statistical parameters for inspecting random simulation runoff sequences, which can supplement the previous test method. To test the new method, we used the monthly runoff simulation series of Luohe Hydrological Station in Huaihe River Basin, Tanghe Hydrological Station in Yangtze River Basin and Heishiguan Hydrological Station in Yellow River Basin as examples. Our evaluation revealed that this new inspection method can effectively find anomalies (ignored by statistical parameters) about flow value and distribution location of the monthly runoff;and estimate the error values of flow and distribution location in simulation sequences of three basins. Compared to the previous inspection method, this new method can screen out the simulation sequences of higher accuracy more effectively, which offers a new way to improve the accuracy of simulation sequences.

关键词： Random simulation Inspection method statistical parameters Sample entropy

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