• Journal of Oral Medicine and Pain
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• v.19 no.2
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• pp.99-110
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• 1994

저자는 저작 수준의 등척성 수축시 하악 폐구근에서의 근전도 스펙트럼의 특성을 규명하기 위하여, 정상 성인 25명을 대상으로 최대수의적 수축의 40% 수준으로 근활성을 2분간 유지하게 하고, 이때 전측두근과 교근에서 얻어진 근전기 신호를 컴퓨터를 이용한 근전도 시스템을 이용하여 분석한 결과 다음과 같은 결론을 얻었다. 1. 저작 수준의 등척성 수축 지속시 시작과 마지막 구간 모두에서 전측두근과 교근의 평균중간주파수와 중간주파수 기울기는 성별 및 연령의 영향을 받지 않았다. 2. 저작 수준의 등척성 수축 지속시 시작과 마지막 구간 모두에서 전측두근과 교근의 평균중간주파수와 중간주파수 기울기는 좌우사이에 통계적으로 유의한 차이가 없었다. 3. 저작 수준의 등척성 수축 지속시 전측두근과 교근의 마지막 구간 평균중간주파수는 시작 구간 평균 중간주파수보다 통계학적으로 유의하게 낮았다.(전측두근 : p<0.01, 교근 : p<0.01). 4. 전측두근과 교근에서 저작 수준의 등척성 수축이 지속됨에 따라 시작 구간과 마지막 구간 모두에서 power spectrum은 저주파 영역으로 이동하였으나, 중간주파수 기울기는 시작 구간과 마지막 구간 사이에 통계적으로 유의한 차이가 없었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.421-421
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• 2017

In order to secure the safety of coastal areas from the continuous storm surge in Korea, it is important to predict the wave movement and properties accurately during the storm event. To improve the accuracy of the storm simulation, and to quantify coastal risks from the storm event, the dependencies between wave height, wave period, and storm duration should be analyzed. In this study, therefore, copulas were used to develop multivariate statistical models of sea storms. A case study of the east coast of Korea was conducted, and the dependencies between wave height, wave period, water level, storm duration and storm interarrival time were investigated using Kendall's tau correlation coefficient. As a result of the study, only wave height, wave period, and storm duration appeared to be correlated.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.3
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• pp.131-139
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• 2014

Infra-gravity waves (IGWs) with a period of 1~3 minutes are a factor that directly influences the motion analysis of moored ships inside a harbor and longshore sediment transport analysis. If significant levels of IGWs from far seas are transferred to a harbor and amplified, they may cause downtime of large ships and induce economic loss. In this study, transfer characteristics of the IGWs intruding from outside to inside Pohang New Harbor were analyzed using statistical analysis and transfer function of wave data measured at both outside and inside the harbor for around 5 years. Transfer characteristic analysis was limited to events where IGWs had wave heights above 0.1 m. The wave height distribution of inside the harbor was similar to that of outside the harbor, while the wave period variance of the former was larger than that of the latter. The parameters of the transfer function was optimally estimated according to each event. The estimated average RMS error of the wave height inside the harbor was around 0.013 m. The estimated parameters had a strong correlation with the linear combination information of IGW wave height, period, and direction (R = 0.95). The transfer function suggested in this study can quickly and easily estimate information on IGWs inside the harbor using IGW information predicted beforehand, and is expected to reduce damage due to unexpected restrictions on harbor usage.

• Spatial Information Research
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• v.15 no.2
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• pp.111-121
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• 2007

The GPS positioning offer 3D position using code and carrier phase measurements, but the user can obtain the precise accuracy positioning using carrier phase in Real Time Kinematic(RTK). The main problem, which RTK have to overcome, is the necessary to have a reference station(RS) when using RTK should be generally no more than 10km on average, which is significantly different from DGPS, where distances to RS can exceed several hundred kilometers. The accuracy of today's RTK is limited by the distance dependent errors from orbit, ionosphere and troposphere as well as station dependent influences like multipath and antenna phase center variations. For these reasons, the author proposes Network based GPS Carrier Phase Differential Positioning using Multiple RS which is detached from user receiver about 30km. An important part of the proposed system is algorithm and software development, named DAUNet. The main process is corrections computation, corrections interpolation and searching for the integer ambiguity. Corrections computation of satellite by satellite and epoch by epoch at each reference station are calculated by a Functional model and Stochastic model based on a linear combination algorithm and corrections interpolation at user receiver are used by area correction parameters. As results, the users can obtain the cm-level positioning.

• Geophysics and Geophysical Exploration
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• v.19 no.4
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• pp.187-199
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• 2016

In order to delineate the soft ground distribution, an integrated geostatistical analysis was performed using the MASW (Multichannel Analysis of Surface Wave) which has the information of overall region and CPTu (Piezo Cone Penetration Test) which provides the direct information of the measuring point of the ground. MASW results were known to have close relationship with the ground stiffness. This correlation was confirmed through the comparison of MASW data obtained from two survey lines to the laboratory test with extracted soil samples. 3D physical property distribution in the study area was acquired by geostatistical integrated analysis with the data of tip resistance ($q_c$) and pore pressure (u) from the CPTu obtained at 6 points within the study area. The integrated analysis was conducted by applying the COSGSIM (Sequential Gaussian Co-Simulation) technology which can carry out the simulation in accordance with the spatial correlation between the MASW results and both tip resistance and pore pressure. Besides the locations of CPTu, borehole investigations were also conducted at two different positions. As a result, the N value of SPT and borehole log could be secured, so these data were used for the analysis of the geotechnical engineering accuracy of the integrated analysis result. For the verification of reliability of the 3D distribution of tip resistance and pore pressure secured through integrated analysis, the geotechnical information gained from the two drilling areas was compared, and the result showed extremely high correlation.

• The Korean Journal of Applied Statistics
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• v.21 no.3
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• pp.429-439
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• 2008

Canonical correlation biplot is 2-dimensional plot for investigating the relationship between two sets of variables and the relationship between observations and variables in canonical correlation analysis graphically. In general, biplot is useful for giving a graphical description of the data. However, this general biplot and also canonical correlation biplot do not give some concise interpretations between variables and observations when the number of observations are large. Recently, for overcoming this problem, Choi and Kim (2008) suggested a method to interpret the biplot analysis by applying the K-means clustering analysis. Therefore, in this study, we will apply their method for investigating the relationship between skill and competition score factors of KLPGA players using canonical correlation biplot and cluster analysis.

• The Korean Journal of Applied Statistics
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• v.28 no.2
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• pp.201-210
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• 2015

Repeated measurements on each variables of interest often arise in bioscience or medical research. We need to account for correlations among repeated measurements to assess the correlation between two variables in the presence of replication. This paper reviews methods to estimate a correlation coefficient between two variables in repeated measurements using the variance-covariance matrix of linear mixed effect models. We analyze acoustic radiation force impulse imaging (ARFI) data to assess correlation between three shear wave velocity (SWV) measurements in liver or spleen and spleen length by ultrasonography. We present how to obtain parameter estimates for the variance-covariance matrix and correlations in mixed effects models using PROC MIXED in SAS.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.378-387
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• 2016

This study sought to investigate interrelationships and differences of brachial-ankle pulse wave velocity (baPWV), body composition and cardiovascular variables between genders who have been exercised or not in elderly. One hundred fifty participants were classified four groups. Especially out of variables, in male elderly group who had participated in exercise program the PWV range were significantly correlated with muscle mass (r=0.357, p=0.026), SBP (r=0.468, p=0.003), right baPWV (r=0.406, p=0.010), and left baPWV (r=0.333, p=0.038). In male elderly group who had not participated in exercise program, the PWV range were significantly correlated with heart rate (r=0.395, p=0.014), right baPWV (r=0.598, p=0.000), and left baPWV (r=0.602, p=0.000). In female elderly group who had participated in exercise program, the PWV range were significantly correlated with name of diagnosis (r=0.321, p=0.044), SBP (r=0.399, p=0.011), DBP (r=0.545, p=0.000), right baPWV (r=0.648, p=0.000), and left baPWV (r=0.676, p=0.000). In female elderly group who had not participated in exercise program, the PWV range were significantly correlated with age (r=0.471, p=0.003), right baPWV (r=0.836, p=0.000), and left baPWV (r=0.801, p=0.000). The PWV among four groups were not significant different after experiment. However, there were significant differences in the waist/hip ratio (F=9.197, p=0.000), muscle mass (F=74.295, p=0.000), and %fat (F=35.045, p=0.000) from body composition. And there were significant differences in the SBP (F=3.525, p=0.017) after experiment. In conclusion, these data show that regular exercise is associated with arterial compliance (PWV range, right or left PWV) and differed from genders. In other words, this paper may support the concept that regular exercise program may exert a protective effect on arterial compliance, body composition and cardiovascular systems.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.463-468
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• 2013

This study was conducted to establish a standard recipe for Bulgogi. For the initial result of the study, the process of establishing standard quality indicators was presented based on surveys with regard to the preferences of the Korean people, American residing in Korea and Americans in USA. A basic recipe was selected based on the preference test. Then additional surveys targeting groups of Korean people, American residents in Korea and Americans were conducted after resetting the contents of soy sauce, sugar, spring onion + garlic of the basic recipe. As a result, differences in preferred seasoning contents between the groups were found. Eventually, the decision for the final recipe of the on-the-spot market search was made.

• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.271-276
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• 2002

The test statistic in ANOVA tests has a single or doubly noncentral F distribution and the noncentral F distribution is applied to the calculation of the power functions of tests of general linear hypotheses. Although various approximations of noncentral F distribution are suggested, they are troublesome to compute. In this paper, the calculation of noncentral F distribution is applied to the neural network theory, to solve the computation problem. The neural network consists of the multi-layer perceptron structure and learning process has the algorithm of the backpropagation. Using fables and figs, comparisons are made between the results obtained by neural network theory and the Patnaik's values. Regarding of accuracy and calculation, the results by neural network are efficient than the Patnaik's values.