• Proceedings of the KSR Conference
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• 2006.11b
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• pp.558-564
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• 2006

When vehicles pass the connection between the bridge and earthwork, the difference of both sections' stiffness produces an increasing wheelload. As a consequence, it results in the excessive vibration of vehicles and the damage of bearing system. In general, steel plate girder railway bridges without ballast track have larger stiffness than the bridge with ballast, and produces larger impulse on the bridge superstructure. Thus, it is necessary to reduce the differences of both stiffness. This study presents parametric studies on the behavior of plate girder bridges and their tracks by means of various stiffnesses and the length of approach zone. The results of numerical study showed that the smaller the stiffness of both sides and the longer the length of approach zone, the variation of wheelload becomes smaller. Hence, it gives less burden into the plate girder bridges and their tracks. It is expected that the results of parametric study can be used as a preliminary data for the determination of economical length on the approach zone and the stiffness of both sides.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.110-111
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• 2019

In ACI 318-19 published recently, the conditions and development length equation to use the headed deformed bars were changed considerably. Although the use of the larger-diameter(No.14 and 18) headed deformed bars isn't yet permitted, the use of the high strength(80,000psi) headed deformed bars is permitted and the effect of bar-diameter($d_b$) on the development length is increased considerably. Therefore, structures using larger-diameter headed deformed bars will be expected to be affected by this code change. We will study the effect of the code change on the development design and find out the design optimization method to minimize the effect of the changed conditions and development length equation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.4_1
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• pp.97-106
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• 1992

Total length of stream networks and main stream length vary with topographic map scales, and the stream length of drainage basin on topographic map can be viewed as a fractal. Total length of stream network and main stream length are represented as only stream area ratio($R_a$) based on Horton's laws, thereafter the fractal dimensions of stream network and main stream length are derived as a simple function of stream length($R_L$) and stream area ratios($R_a$) respectively. The derived equations of fractal dimension are applied to Sansung basin in Kum River and compared with the equations already existed. The stream network appeared as space filling with fractal dimension near 2 as map scale increases, while main stream length shows near 1. The results of this study are expected to be helpful in the quantitative analysis of drainage network composition with map scale.

• Communications for Statistical Applications and Methods
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• v.17 no.2
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• pp.275-292
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• 2010

Receiver operating characteristic(ROC) curves can be used to assess the accuracy of tests measured on ordinal or continuous scales. The most commonly used measure for the overall diagnostic accuracy of diagnostic tests is the area under the ROC curve(AUC). When two ROC curves are constructed based on two tests performed on the same individuals, statistical analysis on differences between AUCs must take into account the correlated nature of the data. This article focuses on confidence interval estimation of the difference between paired AUCs. We compare nonparametric, maximum likelihood, bootstrap and generalized pivotal quantity methods, and conduct a monte carlo simulation to investigate the probability coverage and expected length of the four methods.

• The Research Journal of the Costume Culture
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• v.21 no.2
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• pp.183-194
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• 2013

In recent years, intense cold spells caused by climate change have encouraged an increasing number of people to wear a variety of padded jackets. In this context, this paper aims to address the production of padded jackets in casual brands and to develop basic patterns for well-fitted padded jackets targeted toward women in their 20s. The study centered on the production of padded jackets from 13 apparel companies. In addition, three sample jackets were created with 3oz. fill in the body and 2oz. fill in the sleeves, and they were subjected to a wearing test to determine their movement functionality. The research findings were as follows. Woven jackets constituted 53.4% of the winter jackets produced by casual brands; padded jackets accounted for 25.3%, leather jackets 12.6%, and other jackets 8.7%. Thus, data showed that padded jackets accounted for a considerable proportion of overall winter jacket production. Based on the wearing test results, the basic measurements of a padded jacket for women in their 20s were as follows: bust girth of B/4+3cm front length and B/4+3.5cm back length; waist girth of W/4+3.1 cm front length and W/4+1.9cm back length; and hip girth of H/4+3.3cm front length and H/4+2.8cm back length. The jacket length was set at 62.8cm, with a 63.8cm sleeve length. This study concluded that providing padded jacket manufacturers with basic pattern designs for a well-fitted jacket is expected to boost the efficiency of pattern design processes and the production of padded jackets.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.264-268
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• 2007

Flower and fruit characteristics, in 'Hongro' and 'Galaxy Gala' apples, were investigated by bearing branch lengths and flower bud position such as blow 5 cm, $10{\sim}15cm$ and above 20 cm length with terminal bud, and above 20 cm length with axillary bud for investigation on possibility of alternative use of long bearing branch and axillary bud in case of die-back of spur flower bud. In flowering characteristics by flower bud position in the above 20 cm length, the terminal bud was later and was short in flowering period, and also was little in number of flower per bud. Fruit weight, number of seeds, and sugar-acid ratio, in characteristics of ripening fruit, were more the blow 5 cm and $10{\sim}15cm$ length, but soluble solid and malic acid contents was the opposite tendency. In fruit characteristics by flower bud position in the above 20 cm length, the terminal bud had high tendency expected far number of seed in 'Hongro' and Hunter a value of 'Galaxy Gala' apple but had not significant difference. Correlation between fruit weight and number of seed was high. As the results, value of alternative use of long bearing branch in apples had a little expected for fruit weight, especially was more 'Galaxy Gala' and the axillary bud.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.1
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• pp.21-29
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• 2015

A steady-state controllable M/G/1 queueing model operating under the {T:Min(T,N)} policy is considered where the {T:Min(T,N)} policy is defined as the next busy period will be initiated either after T time units elapsed from the end of the previous busy period if at least one customer arrives at the system during that time period, or after T time units elapsed without a customer' arrival, the time instant when Nth customer arrives at the system or T time units elapsed with at least one customer arrives at the system whichever comes first. After deriving the necessary system characteristics including the expected number of customers in the system, the expected length of busy period and so on, the total expected cost function per unit time for the system operation is constructed to determine the optimal operating policy. To do so, the cost elements associated with such system characteristics including the customers' waiting cost in the system and the server's removal and activating cost are defined. Then, procedures to determine the optimal values of the decision variables included in the operating policy are provided based on minimizing the total expected cost function per unit time to operate the queueing system under considerations.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.1
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• pp.96-103
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• 2014

A steady-state controllable M/G/1 queueing model operating under the (TN) policy is considered where the (TN) policy is defined as the next busy period will be initiated either after T time units elapsed from the end of the previous busy period if at least one customer arrives at the system during that time period, or the time instant when Nth customer arrives at the system after T time units elapsed without customers' arrivals during that time period. After deriving the necessary system characteristics such as the expected number of customers in the system, the expected length of busy period and so on, the total expected cost function per unit time in the system operation is constructed to determine the optimal operating policy. To do so, the cost elements associated with such system characteristics including the customers' waiting cost in the system and the server's removal and activating cost are defined. Then, the optimal values of the decision variables included in the operating policies are determined by minimizing the total expected cost function per unit time to operate the system under consideration.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.2
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• pp.37-45
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• 2016

Control chart is representative tools of statistical process control (SPC). It is a graph that plotting the characteristic values from the process. It has two steps (or Phase). First step is a procedure for finding a process parameters. It is called Phase I. This step is to find the process parameters by using data obtained from in-controlled process. It is a step that the standard value was not determined. Another step is monitoring process by already known process parameters from Phase I. It is called Phase II. These control chart is the process quality characteristic value for management, which is plotted dot whether the existence within the control limit or not. But, this is not given information about the economic loss that occurs when a product characteristic value does not match the target value. In order to meet the customer needs, company not only consider stability of the process variation but also produce the product that is meet the target value. Taguchi's quadratic loss function is include information about economic loss that occurred by the mismatch the target value. However, Taguchi's quadratic loss function is very simple quadratic curve. It is difficult to realistically reflect the increased amount of loss that due to a deviation from the target value. Also, it can be well explained by only on condition that the normal process. Spiring proposed an alternative loss function that called reflected normal loss function (RNLF). In this paper, we design a new control chart for overcome these disadvantage by using the Spiring's RNLF. And we demonstrate effectiveness of new control chart by comparing its average run length (ARL) with ${\bar{x}}-R$ control chart and expected loss control chart (ELCC).

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.181-190
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• 2007

Objective : The purpose of this study is to understand preferences of patients who had visited the Dept. of Ophthalmology Otolaryngology & Dermatology Method : We conducted questionnaire survey on the patients who had visited the Dept. of Ophthalmology, Otolaryngology & Dermatology Hospital of Dong Shin University from March to September, 2007. Result : The result were as follows. 1. Distribution of sex: male 41 % female 59% 2. The age distribution of patients showed highest in 30-39 years(23%), followed by 20-29 years, 40-49 years in order. 3. The classification of patients according to disease: Skin disease (38%), Nose (23%), Face (10%), Eye (9%), Throat (8%), Ear (7%) 4. Other offices patients visited before coming to this clinic: Local clinic (41%). Hospital (18%), Oriental clinic or hospital (5%), None (22%) 5. The length of time the patient has had the disease: 2years (26%), more than 3years (15%), 2-4weeks (13%), 6months (11%), 1year (10%) in order 6. The expected length of treatment: 1week (21%), 2week (12%), 1month (21%) 7. 26% expected about 100,000 won as medical expenses. 8. 88% of the patients are willing to have a check-up when it needed and 40% expected about 50,000 won as check-up expenses. 9. 52% of the patients are not willing to withstand pain, and would rather heal slowly. 10. 69% of the patients said that treatment would be affected by company(44%), school(19%) and business(16%). 11. 73% of the respondants are positive about night-time treatment and 92% is positeve about making an appointment for the treatment. Conclusion : Through the research, we could understand preferences of patients who had visited Dept. of Ophthalmology, Otolaryngology & Dermatology