• Journal of Korean Clinical Health Science
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• v.7 no.2
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• pp.1337-1344
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• 2019

Purpose. This study was the analyze the refractive status of presbyopia in Korea. Methods. The subjects was from November 2018 to October 2019, two hundred thirty four subjects( 117 male subjects, 117 female subjects; from 40-year old to 88-year old ) were performed in refraction test using the Auto-Refraction(Speed -K model, Japan). The myopia, hyperopia, astigmatism, and anisometropia were defined as spherical equivalent(SE)≤-0.50 diopters, SE ≥+1.00 D, cylinder error ≥0.75 D and SE difference≥1.00 D between binocular eyes, respectively. Results. The refractive status by spherical equivalent among all subjects was myopia 61.43%, astigmatism 86.86%, emmetropia 19.18%, anisometropia 12.07%, and hyperopia 18.54. The prevalence of myopia and astigmatism were much more common in male. However, The hyperopia and astigmatism were much more common in female. The prevalence of spherical equivalent was much common from -0.50 diopter to -5.00 diopter. On the other hand, the prevalence of astigmatism and myopia was much more than hyperopia in all subjects. There was a statistical significance between OD and OS of the female and male in the spherical equivalent power(p<.000). However, there was not statical significant between female and male of OD and OS in the spherical equivalent power(p<.070). On the other hand, The prevalence of againest axis in astigmatism was more common in all subjects. In ADD power for the near vision correction, the female was much more diopter than male. Conclusions. These results suggested that the analysis of the refractive status on the presbyopia in Korea can give the useful diagnosis data for the correction of visual acuity at near distance.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.857-864
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• 2005

Purpose : The objectives of this study was to evaluate the correlations between the indices of insulin sensitivity using fasting glucose and insulin level, and the body fat mass measured by bioelectrical impedance analysis(BIA) and dual energy X-ray absorptiometry(DEXA), and to determine the clinical usefulness of insulin sensitivity indices when obese children were followed up. Methods : In this study, 28 simple obese children and adolescents were included. Anthropometric data including body weight, height, obesity degree(OD), body mass index(BMI), and waist-to-hip ratio were collected and then body fat mass was measured by using BIA and DEXA. For metabolic data, 12 hour fasting serum glucose, insulin and lipid profiles were measured and indices for insulin sensitivity(G/I ratio, $log_{insulin}$, HOMA-IR, $log_{HOMA-IR}$, QUICKI) were calculated. Results : BMI had a higher correlation with insulin sensitivity indices than OD(G/I ratio, -0.463 vs -0.209; $log_{insulin}$, 0.417 vs 0.196; HOMA-IR, 0.301 vs 0.238; $log_{HOMA-IR}$, 0.403 vs 0.198; QUICKI, -0.451 vs -0.224). But OD had a higher correlation with body fat mass measured by BIA and DEXA than BMI(BIA, 0.612 vs 0.316; DEXA, 0.667 vs 0.512). The G/I ratio was correlated with body fat mass in BIA(r=-0.420, P<0.05) and DEXA(r=-0.512, P<0.01), percentage of body fat(percentage of fat) in BIA(r=-0.366, P<0.05) and DEXA(r=-0.449, P<0.01). HOMA-IR was only correlated with body fat mass in DEXA(r=0.341, P<0.05). Conclusion : This study revealed that G/I ratios had a statistically significant correlation with anthropometric obesity indices(OD and BMI) and also had a correlation with both body fat mass and percentage of fat. These results suggest that G/I ratios could be used as useful index when obese children and adolescence are followed up.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.205-215
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• 2008

As static traffic assignment has reached its limitation with ITS policy applications and due to the increase of interest in studies of ITS policies since the late 1980's, dynamic traffic assignment has been considered a tool to overcome such limitations. This study used the Dynameq program, which simulates route choice behavior by macroscopic modeling and dynamic network loading and traffic flow by microscopic modeling in consideration of the feasibility of the analysis of practical traffic policy. The essence of this study is to evaluate the feasibility for analysis in practical transportation policy of using the dynamic traffic assignment technique. The study involves the verification of the values estimated from the dynamic traffic assignment with South Korea's expressway network and dynamic O/D data by comparing results with observed link traffic volumes. This study used dynamic O/D data between each toll booth, which can be accurately obtained from the highway Toll Collection System. Then, as an example of its application, exclusive bus-lane policies were analyzed with the dynamic traffic assignment model while considering hourly variations.

• Spatial Information Research
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• v.18 no.3
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• pp.41-52
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• 2010

This paper analyzed the interregional flow changes of software (SW) industries using a GIS Flow Map. Employment data for SW enterprise headquarters from 1999 until 2008 were constructed according to the Origin-Destination Matrix, and were mapped and analyzed using the Flow Mapper and ArcGIS Flow Data Model. From the result we can identify the decentralization of interregional flow in SW industries and recognize the possibilities of the larger SW enterprises' employment, the higher locational footlooseness. The GIS Flow Map was identified as useful tool for researching growth, decline and spatial movement of industrial clusters that experience business relocation. This method can be applied to understand and visualize urban spatial changes.

• Proceedings of the Korea Port Economic Association Conference
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• 2007.07a
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• pp.493-514
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• 2007

A Port is, one of the important infrastructures, the terminal to connect between land and sea and exerts influences on the development of nation and local area. Accordingly government and privates are making an investment in port facilities in order to raise its competitive power. Due to the economic growth of China and the geographic advantage that Gunsan and Janghang port are close to China, recently traffic with China is rapidly increasing and the role of Gunsan & Janghang ports as a gateway port of west costbecame more important. There, however, remains that Gunsan and Janhang port still don't equipped with enough facilities and strategies to handle increasing traffic. The purpose of this paper is to analyze O/D data of Gunsan-Janghang Port and present the result of O/D as preliminary data. O/D data of Gunsan and Janghang had been analyzed by kinds of cargoes and from/to China's ports and this paper suggests to the competitive strategies of Gunsan and Janghang port to attract cargoes from/to China particularly.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.3
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• pp.285-293
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• 1998

This paper presents an experimental study on condensing heat transfer characteristics of R-22 alternative refrigerants, R-290 and R-410a on water sources heat pump. The apparatus mainly consisted of vapor pump condenser used to the test section evaporator manual expansion valve and measuring device. Test section constructed a smoothed tube of 10.07 mm ID and 12.7mm OD with a total length 6,300 mm was horizontal double pipe counterflow condenser. The refrigerants R-22, R-290 and R-410a were cooled by a coolant circulated in a surrounding annulus. Experimental range of mass velocities was changed from about 100 to 300 kg/($m^2$.s) and inlet quality 1.0 The credibility of experimental apparatus was 6 percent between heating capacity and cooling capacity added to compressor shaft power. The condensing heat transfer coefficients were increased with increasing mass velocity. However in case of R-290 they were more increasing than those of R-410a and R-22 Comparing the heat transfer coefficient between the experimental data and other's data the Cavallini-Zecchin's data was revealed to more similar prediction of author's experimental results on the average heat transfer coefficients.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.34.2-34.2
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• 2008

The batch least square filter is widely used for ground estimations. However, in orbit determination (OD) under inaccurate initial conditions and few measurement data the performance by the batch least square filter can lead an unstable results. To complement weak part of the batch filter, the batch unscented transformation without any linearization process is developed by ACL (Astrodynamics and Control Laboratory) in YONSEI University. In this paper, the batch unscented transformation is introduced and applied to satellite orbit determination using Satellite Laser Ranging (SLR) data. Only range of the satellite measured from ground tracking stations is used for measurement data. The results of simulation test are compared with those of the weighted batch least square filter for various initial states errors (position and velocity). Simulation results show that the batch unscented transformation is comparable or slightly superior to batch least square filter in the orbit determination.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.929-932
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• 2012

Beat map shows the distribution property of the beating sound in the bell structure. Using the beat map, beat control and beat estimation are available. To draw the beat map, mode pair parameters of the bell are required. However, in case of large bell which is struck by a heavy wooden hammer, it is very difficult to measure the excitation force and to obtain the mode pair parameters. In this paper, we determined the mode pair parameters of the bell from the transmissibility between the roving signal and reference signal, using ODS(operational deflection shape) method. The mode pair data are input to the theoretical model of the beat response and beating waves are generated on the bell circumference. All the numerical and beat map drawing procedures are automatized using Matlab. Finally, the reliability of the beat map generated by the program is verified.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.3
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• pp.10-18
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• 2001

The purpose of this study is to research the influence of soundscape in the preference of landscape. Specifically, Standards types of communications are applied to the landscape such as artificial waterscapes and natural valley. The spatial image was analyzed by the variables of Kaplan´s information processing model. The level of visual preferences was measured by a type of acoustic information in landscape and media of communication, and these data were analyzed by multiple regression. The results of this study can be summarized as follows; The value of landscape preference was not different from all fluent of coherence, complexity, legibility ,mystery and preference utilized the communication media, but it was different by the type of acoustic information in landscape. These results clearly show the influence of sound affecting decisions of landscape preference. The factors determining the level of landscape preference were found to be coherence, complexity, legibility, mystery and dummy variables of acoustic information in landscape and media od communication. These variables amy be the major factors which must be considered on planning and designing as the functional basis for the quantitative analysis.

• Korean Journal of Rural Living Science
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• v.9 no.1
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• pp.79-95
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• 1998

The purpose of this study is to investigate quality of life in farm households. This study examines some related factors which influence the well-being of the family life among the rural housewives, based on the farm management, household management, the satisfaction of the household and the satisfaction of community. Questionnaires were distributed to the 200 housewives residing in Anseong. The 187 data obtained were analyzed by frequency, percentage and mean. Based on the above findings, it has been found that the role od the rural housewives is very important. Because they works not only at home but also in work. The satisfaction of rural housewives about family living and community is very low. In order to improve work, work course should be mechanized. If greater attentions should be directed to the satisfaction of leisure activities, the quality of family life could be improved and stabilized.