• The Korean Journal of Applied Statistics
• /
• v.19 no.3
• /
• pp.431-445
• /
• 2006

In this paper we review some methods for analyzing functional data and illustrate real application of functional data analysis. Representing methods for functional data by using basis function, analyzing functional variation by functional principal component analysis and functional linear models are reviewed. For a real application, we use temperature and precipitation data measured in Korea from the January of 1970 to the May of 2004. We apply functional principal component analysis for each data and test the significance of regional division done by using shining hours. We also estimate functional regression model for temperature and precipitation.

• Communications for Statistical Applications and Methods
• /
• v.29 no.1
• /
• pp.103-125
• /
• 2022

In this paper, we analyze the time series data of the case and death counts of COVID-19 that broke out in China in December, 2019. The study period is during the lockdown of Wuhan. We exploit functional data analysis methods to analyze the collected time series data. The analysis is divided into three parts. First, the functional principal component analysis is conducted to investigate the modes of variation. Second, we carry out the functional canonical correlation analysis to explore the relationship between confirmed and death cases. Finally, we utilize a clustering method based on the Expectation-Maximization (EM) algorithm to run the cluster analysis on the counts of confirmed cases, where the number of clusters is determined via a cross-validation approach. Besides, we compare the clustering results with some migration data available to the public.

• Communications for Statistical Applications and Methods
• /
• v.28 no.2
• /
• pp.135-150
• /
• 2021

We propose principal differential analysis based classification methods. Computations of squared multiple correlation function (RSQ) and principal differential analysis (PDA) scores are reviewed; in addition, we combine principal differential analysis results with the logistic regression for binary classification. In the numerical study, we compare the principal differential analysis based classification methods with functional principal component analysis based classification. Various scenarios are considered in a simulation study, and principal differential analysis based classification methods classify the functional data well. Gene expression data is considered for real data analysis. We observe that the PDA score based method also performs well.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.2 no.2
• /
• pp.52-60
• /
• 1999

By implementing the Systems Engineering process for the aircraft preliminary design, functional analysis study is performed, hence Functional Interface Data Flow(FIDF) and Functional Flow Block Diagram(FFBD) are generated. Based on FIDF and FFBD, allocable and non-allocable design/performance/RM＆S requirements are allocated to the appropriate levels. Weight and cost tracking and design margin management methodologies are studied and implemented for the balanced aircraft design.

• Proceedings of the KSR Conference
• /
• 2008.06a
• /
• pp.1880-1886
• /
• 2008

Recently, a railroad system has a big and complicated structure of specification. Therefore, traceability between specification need to be identified for design change management and this is many engineer's concerns. Traceability means technical relationship. This is to trace other specification or component connect with relevant problem in case some problem should be examined. Traceability between functional specification can be proved through functional analysis essentially. This study will introduce an application method of functional analysis in the case of practical use project of MAGLEV train. And we propose the guide to identify traceability between function through functional analysis.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.3
• /
• pp.334-340
• /
• 2007

The purpose of this study is to analyze silver consumers' life style, and whether silver consumers ’ life style have an effect on purchase satisfaction and repurchase intention of the health functional foods. To this end, a survey was conducted from May 28 to June 20 in 2007, among silver consumer aged in over 50s, on their purchase experience of the health functional foods. The survey was conducted with 326 subjects, and the statistical analysis methods were frequency analysis, factor analysis, and multiple regression analysis. According to the result of this study, First, the silver consumers' life style factors were determined to be health and leisure pursuit, material pursuit, family pursuit, and outgoing challenge pursuit. And purchase satisfaction factors of the health functional foods were determined to be taking after dosage and service, function and purchase, appearance of health functional foods. Second, silver consumers' family pursuit life style and outgoing challenge life style had an effect on taking and service satisfaction, appearance and products satisfaction of the health functional foods. Third, purchase satisfaction had an effect on repurchase intention of the health functional foods. Therefore, this study is significant in that it clarifies the relation of silver consumers' life style and purchase satisfaction and repurchase intention of the health functional foods.

• Proceedings of the KSR Conference
• /
• 2002.10a
• /
• pp.202-207
• /
• 2002

The rubber type AGT system is operated by driverless that signaling is CBTC type. The system function is acomplished exactly to obtain the safety and reliability of system and the system is designed to minimize risk. In order to design the system, the functional analysis is performed. Recently functional analysis is performed by RDD-100 which is used and verified by aerospace, military, etc. Therefore, The design tool RDD-100 is used to perform functional analysis in AGT system development project.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.3
• /
• pp.977-991
• /
• 2000

In this paper, a medical image processing system was designed and implemented for morphometric and functional analysis of a human brain. The system is composed of image registration, ROI(region of interest) analysis, functional analysis, image visualization, 3D medical image database management system(DBMS), and database. The software processes an anatomical and functional image as input data, and provides visual and quantitative results. Input data and intermediate or final output data are stored to the database as several data types by the DBMS for other further image processing. In the experiment, the ROI analysis, for a normal, a tumor, a Parkinson's decease, and a depression case, showed that the system is useful for morphometric and functional analysis of a human brain.

• Proceedings of the KIEE Conference
• /
• 2005.10c
• /
• pp.299-301
• /
• 2005

The urban transit system is operated by driverless and automatic.In driverless and automatic system, the system function is accomplished exactly to obtain the safety and reliability of system and the system is designed to minimize risk. In order to design the system, the functional analysis is performed. Recently functional analysis is performed by design toolwhich is used and verified by aerospace, military, etc. Generally, the design tool is used to perform functional analysis in urban transit system development project. The design toolassist the system engineer to analysis the function of system in basic design. Therefore, In this paper, it is performed the functional analysis to satisfy the system requirement of urban transit system and to confirm the operation of system using design tool.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1663-1665
• /
• 2005

The urban transit system is operated by driverless and automatic. In driverless and automatic system, the system function is accomplished exactly to obtain the safety and reliability of system and the system is designed to minimize risk. In order to design the system, the functional analysis is performed. Recently functional analysis is performed by design tool which is used and verified by aerospace, military, etc. Generally, the design tool is used to perform functional analysis in urban transit system development project. The design toolassist the system engineer to analysis the function of system in basic design. Therefore, in this paper, it is performed the functional analysis to satisfy the system requirement of urban transit system and to confirm the operation of system using design tool.