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Usefulness of the SNR Using the Subtraction Method and Image Visibility Using the Howlett chart Method in X-Ray Fluoroscopic System

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Open Journal of Medical Imaging 2014年第2期4卷 49-56页

作者： Sadamitsu Nishihara Yuki Yamashita Naoki Kawai Hideki Otsuka Department of Radiological Technology Tokushima University School of Health Sciences Tokushima Japan Department of Radiology Kansai Electric Power Hospital Osaka Japan Department of Radiological Technology Tokushima University School of Health Sciences Tokushima Japan Department of Radiological Technology University of Miyazaki Hospital Miyazaki Japan Subdivision of Biomedical Information Sciences Institute of Health Biosciences University of Tokushima Graduate School Tokushima Japan

X-ray fluoroscopy has been used not only for diagnoses but also for treatment, as in interventional radiology. The aim of this study is to assess the usefulness of the signal-to-noise ratio (SNR) using the subtraction method, which is used in the quality assurance/quality control (QA/QC) of magnetic resonance imaging (MRI) equipment, and image visibility using the Howlett chart method in the fluoroscopic examination. The fluoroscopy unit has a detector with an image intensifier and a color liquid crystal display. A 2620 dosimeter and an ionization chamber were selected for the dose measurement. Fluoroscopic images for visual and physical evaluations were collected as dynamic data. The skin surface absorbed dose rates for each tube current were measured using a dosimeter. The SNR using the subtraction method and image visibility using the Howlett chart method were examined. The results from both indicate that as the SNR improves, visual evaluation increases, but the rate of increase gradually saturates. Therefore, physical and visual evaluations are possible with the SNR using the subtraction method and the image visibility using the Howlett chart method.

关键词： X-Ray Fluoroscopic System Signal-to-Noise Ratio Howlett chart Visibility

Hydrogen Engine and Numerical Temperature-Entropy chart for Hydrogen/Air Cycle Analysis

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Energy and Power Engineering 2015年第9期7卷 375-383页

作者： Elsayed M. Marzouk Hamza A. Ghulman Mechanical Engineering Department College of Engineering and Islamic Architecture Umm Al-Qura University Makkah KSA

Fast depletion of fossil fuels with its resources already passed its mid depletion region and the pollution levels already reached unsafe levels which make it utmost necessity to search for alternative fuels to meet sustainable energy demand with minimum environmental impact. Among alternative fuels, hydrogen is considered as the near future, long term renewable, sustainable and non-polluting fuel. In the present paper, hydrogen fueled internal combustion engine fundamentals highlighted and presented relating to hydrogen combustion properties. A Mat lab programmed hydrogen temperature-entropy-energy chart is developed and presented for fresh charge and products of combustion at different excess air factors per mole combustion gases. The chart, then, used to represent a SI hydrogen-fueled fuel/air cycle analysis, which proved to be valuable design tool for engine sizing and for prediction of engine performance. Predictions carried out using the hydrogen F/A cycle analysis at different λ show low brake specific fuel consumption and low volume specific power compared with conventional SI engine.

关键词： Hydrogen Engine H2-Combustion Properties H2-Fueled SI Engine Temperature-Entropy chart Fuel/Air Cycle Analysis

On the charting Procedures: MEWMA chart and DD-Diagram

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Open Journal of Statistics 2015年第5期5卷 373-381页

作者： Mekki Hajlaoui Faculté des Sciences Economiques et de Gestion de Mahdia Université de Monastir Mahdia Tunisia

In light of rapid development of customer requirements, control procedures of quality concept use multivariate analysis. This is because of recent advances in information technology and in recording. The charting procedures are based on Mahalanobis distance but their performance needs normality and a type-I error rate choice. The DD-diagram is an alternative scheme that uses data depth to avoid these conditions rarely met in practice. For a given error-free sample, the performance of DD-diagram and that of multivariate EWMA control procedures are compared through a real example on individual observations taken from a multivariate quality process.

关键词： Multivariate Data Quality Control Mahalanobis Distance MEWMA chart Data Depth DD-Diagram

Analysis of the Effect of Subgroup Size on the X-Bar Control chart Using Forensic Science Laboratory Sample Influx Data

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Engineering（科研） 2017年第5期9卷 434-456页

作者： Samwel Victor Manyele Department of Forensic Science and DNA Services Government Chemist Laboratory Authority (GCLA) Dar es Salaam Tanzania

This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules.

关键词： Forensic Science Laboratory Sample Influx Statistical Analysis X-bar Control chart Sub-Group Size Control chart Rules Multi-Rules for X-Bar chart Out-of-Control Points

THE NATURAL SYSTEM OF NUCLIDES AND 'VALLEY-LIKE' chart OF NUCLIDES

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中国科学A辑(英文版) 1986年第5期 502-509页

作者：王端 Beijing Printing Institute

When studying the compositions of various atomic nuclei and characteristic parameters of various nuclides, we notice their different compositions and different ground-state atomic masses of nuclides respectively. In the further comprehensive investigation, it has been found that there exists a universal and ratified intrinsic connection between the ground-state atomic masses of various nuclides and compositions of various atomic nuclei.In order to explain and show this intrinsic connection specifically, a new chart of nuclides has been established. This new chart is called 'valley-like' chart of nuclides for the moment (new chart for short in this paper).

关键词： chart nuclei valley intrinsic universal specifically explain horizon longitudinal proton

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基于期待类型的chart句法分析算法

计算机应用 2009年第5期29卷 1251-1253页

作者：王燚李中志成都信息工程学院网络工程系成都610225

chart算法是目前句法分析中应用最广泛的算法之一,但该算法的计算效率仍有待提高。通过对两种常用chart算法的分析,提出一种以由底向上的chart算法为基础,结合自顶向下chart算法的预测能力的算法。算法按严格从左到右、由底向上的方向进... 详细信息

chart算法是目前句法分析中应用最广泛的算法之一,但该算法的计算效率仍有待提高。通过对两种常用chart算法的分析,提出一种以由底向上的chart算法为基础,结合自顶向下chart算法的预测能力的算法。算法按严格从左到右、由底向上的方向进行,根据已有活动边的活动角色类型和句法规则,产生当前词位置上的期待类型表,并以此限制后续边的生成。对比实验的结果表明,分析速度较普通chart算法提高了约24%,同时也减少了一半以上因边池溢出而导致的分析失败的语句。

关键词：自然语言处理句法分析 chart

Variable selection-based SPC procedures for high-dimensional multistage processes

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Journal of Systems Engineering and Electronics 2019年第1期30卷 144-153页

作者： KIM Sangahn Department of Business Analytics and Acturial Science Siena College

Monitoring high-dimensional multistage processes becomes crucial to ensure the quality of the final product in modern industry environments. Few statistical process monitoring(SPC) approaches for monitoring and controlling quality in highdimensional multistage processes are studied. We propose a deviance residual-based multivariate exponentially weighted moving average(MEWMA) control chart with a variable selection procedure. We demonstrate that it outperforms the existing multivariate SPC charts in terms of out-of-control average run length(ARL) for the detection of process mean shift.

关键词： diagnosis procedure deviance residual fault identification model-based control chart multistage process monitoring variable selection.

Design of crown pillar thickness using finite element method and multivariate regression analysis

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International Journal of Mining Science and Technology 2017年第6期27卷 955-964页

作者： Kumar Hemant Deb Debasis Chakravarty D. Department of Mining Engineering Indian Institute of Technology (Indian School of Mines) Dhanbad 826004 India Department of Mining Engineering Indian Institute of Technology Kharagpur 721302 India

Minerals are now being extracted from deep mines due to drying up of resource in shallow ground. The need for suitable supports and ground control mechanisms for safe mining necessitates proper pillar design with filling technology. In addition, high horizontal stress may cause collapse of hanging wall and footwall rocks, hence designing of suitable crown pillars is absolutely necessary for imposing overall safety of the stopes. This paper provides a methodology for the evaluation of the required thickness of crown pillars for safe operation at depth ranging from 600 m to 1000 m. Analyses are conducted with the results of 108 non-linear numerical models considering Drucker-Prager material model in plane strain condition. Material properties of ore body rock and thickness of crown pillars are varied and safety factors of pillars estimated. Then, a generalized statistical relationship between the safety factors of crown pillars with the various input parameters is developed. The developed multivariate regression model is utilized for generating design/stability charts of pillars for different geo-mining conditions.These design charts can be used for the design of crown pillar thickness with the depth of the working,taking into account the changes of the rock mass conditions in underground metal mine.

关键词： Cut and fill mining Crown pillar FEM Regression model Design chart

SHARED VALUE IN A FINITE-DIMENSIONAL BANACH MANIFOLD

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Acta Mathematica Scientia 2010年第5期30卷 1687-1695页

作者： J.M.Soriano Departamento de Ana'lisis Matem'atico Facultad de Matema'ticasUniversidad de Sevilla

Sufficient conditions are given to assert that two C1-mappings share only one value in a connected compact Banach manifold modelled over Rn. The proof of the result, which is based upon continuation methods, is constr... 详细信息

关键词： regular value continuation methods atlas chart Banach manifold compactness