• Journal of Korean Tunnelling and Underground Space Association
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• v.6 no.1
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• pp.61-70
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• 2004

Precast Concrete Lining (PCL) is invented in order to resolve the problem of the cast-in-place concrete lining in Norway, However PCL could not consider the effect of earthquake because an earthquake rarely occurs in the region of Northern Europe, Consequently, the analysis of the effect of earthquake on PCL should be made before introducing PCL to Korea. The purpose of this research is to evaluate the stability of tunnel applying PCL in the case of earthquake. To evaluate the seismic performance of PCL, we used shaking table apparatus by 1/5 scale down model. The result of this research is as shows that deep tunnells satisfied for Korea seismic design criteria.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.529-540
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• 2016

Objective: The objective of this study was to evaluate the osseointegration of narrow-diameter implant with trapezoid-shape and to evaluate the effect of coronal microthreads on trapezoid-shape narrow-diameter implant. Materials and Methods: The experimental narrow-diameter implants were classified into two groups according to absence or presence of coronal microthreads: trapezoid-shape narrow diameter implant (TN group) and trapezoid-shape narrow-diameter implant with microthreads (TNM group). They were installed alternately in bilateral mandible in three dogs. After 8 weeks, the animals were sacrificed. Resonance frequency analysis, removal torque test, and histometric analysis were performed. Results: Statistically higher implant stability quotient (ISQ) values were observed in TNM group than in TN group at the time of implant installation. However, significant ISQ values difference was not observed between groups at 8 weeks. Both groups showed significantly increased ISQ values at 8 weeks, compared to the time of implant installation. There was no significant difference between groups in removal torque test. Bone-implant contact ratio also showed no significant difference between groups in total and coronal part. Conclusion: Within the limitation of this study, it could be concluded that the trapezoid-shape design on narrow-diameter implant showed successful ossointegration, and the microthreads on coronal part did not result in significant bone-implant contact and biomechanical stability at 8 weeks.

• Journal of Korean Academy of Nursing
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• v.38 no.4
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• pp.582-592
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• 2008

Purpose: The purpose of this research was to analyze the effects of an eye protective device and ear protective device application on sleep disorder with coronary disease patients in CCU. Methods: The research design was set up as a nonequivalent control group non-synchronized design. The subjects were coronary disease patients in the CCU of a tertiary hospital. The subjects were composed of 20 in the group with an eye protective device, 18 in the group with an ear protective device, 17 in the group with an eye protective device and ear protective device and 20 in the control group. The data was analyzed by $X^2-test$, ANOVA, Repeated measures ANOVA, Sheffe-test, Simple main effect and Time contrast using SPSS Win 12.0. Results: The hypothesis, 'There are significant differences in sleep quantity among the four groups' was supported (F=1,342.71, p=.000). The hypothesis, 'There are significant differences in the subjective evaluation of the general sleep patterns among the four groups' was supported (F=3,638.73, p=.000). In addition the hypothesis, 'There are significant differences in degree of sleep among the four groups' was supported (F=1,616.61, p=.000). Conclusion: It is cost effective and a simple eye protective device and ear protective device should be applied to patients according to their preference and characteristics in the clinical setting.

• The Journal of the Acoustical Society of Korea
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• v.15 no.1E
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• pp.5-19
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• 1996

This paper proposes a loose part monitoring system (LPMS) design with a signal processing method based on fuzzy logic. Considering fuzzy characteristics of metallic impact waveform due to not only interferences from various types of noises in an operating nuclear power plant but also complex wave propagation paths within a monitored mechanical structure, the proposed LPMS design incorporates the comprehensive relation among impact signal features in the fuzzy rule bases for the purposes of alarm discrimination and impact diagnosis improvement. The impact signal features for the fuzzy rule bases include the rising time, the falling time, and the peak voltage values of the impact signal envelopes. Fuzzy inference results based on the fuzzy membership values of these impact signal features determine the confidence level data for each signal feature. The total integrated confidence level data is used for alarm discrimination and impact diagnosis purposes. Through the perpormance test of the proposed LPMS with mock-up structures and instrumentation facility, test results show that the system is effective in diagnosis of the loose part impact event(i.e., the evaluation of possible impacted area and degree of impact magnitude) as well as in suppressing false alarm generation.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.3
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• pp.427-436
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• 2016

Protective clothing developed for rose flower farmers has been evaluated to improve the working conditions. The requirements of rose farmers were first identified to design protective clothing for farmers working with thorny plants. A fit test was conducted to assess the thermal comfort and protective function against thorn pricking to compare and evaluate the usability of developed experimental clothing with existing working clothes. Based on the survey results of rose farmers' requirements, protective clothing was designed in the form of an apron (which was the most preferred after gloves) with a pattern designed for the production of experimental clothing. For the developed protective clothing, the strap and buckle closure method was selected to open the back of the body as much as possible; in addition, sleeves were made in the attachable form of a half-sleeve to protect the arms from the thorns. The fit test of the developed protective clothing and existing working clothes revealed the temperature and humidity inside the developed protective clothing to be significantly different in the back compared to existing work clothes. In addition to thermal sensations, the subjective humidity sensations were statistically significant different in the developed protective clothing compared to existing work clothes. The subjective protective function for thorn pricking was also found to be satisfactory.

• Journal of the Korean Data and Information Science Society
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• v.28 no.6
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• pp.1437-1445
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• 2017

This paper suggests a temperature guidance which must be addressed in the preparation of specifications for military equipment used in ocean/coastal environment of the Korean peninsula. It would often be costly to design materiel to operate under the most extreme environmental conditions ever recorded. Therefore, military planners usually accept equipments designed to operate under environmental stresses for all the time except a certain small percentage of the time. In this study, an 1-percent frequency of occurrence is recommended. Pohang and Shineiju are chosen to represent the hottest and coldest regions, respectively, based on surface weather observations among 28 costal regions from 1904 to 2015. The 1st and 99th percentile temperatures for Pohang and Shineiju are $37.7^{\circ}C$ and $-23.7^{\circ}C$, respectively. Diurnal cycles, including solar radiation, relative humidity and wind-speed are also provided.

• Journal of the Korean GEO-environmental Society
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• v.14 no.2
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• pp.51-55
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• 2013

Among various construction methods, deep soil stabilization by chemical method have been widely used in order to improve soft ground. Dynamic variables using ground(such as sand, weathered granite soil and rock) -structure interaction design affected by dynamic load and cyclic load were studied a lot. However, there is something yet to learn about earthquake resistant design regarding reinforced ground by grout. Therefore, in this study using RC test, the correlation between shear strain and shear modulus with change of water content and injection rate in normal portland cement and clay was compared and analyzed by using Ramberg-Osgood model normalization As the result, dynamic coefficient was considerably affected by water content and grout injection rate.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.11
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• pp.963-970
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• 2016

This research deals with design and performance validation of eco-pedals that generate tactile pedal force to guide fuel saving driving behavior. For eco-pedal control logic, allowable fuel consumption at given driving speed is calculated based on pre-defined "allowable acceleration", and if the actual fuel consumption exceeds the allowable fuel consumption, then pedal force is activated. Pedal force should be recognizable to driver while not causing unpleasantness, and should not interfere with normal operation of pedal. Reaction forces that increase pedal stiffness abruptly, such as step and ramp shape, turn out to be not suitable due to pedal overshoot after release of reaction force. With this regards, vibration type reaction force is adopted, and its optimal frequency, magnitude and duration is determined through subjective evaluation with consideration to effect to fuel efficiency. Though highway and city driving test, it is demonstrated that fuel efficiency increase of 13% for highway and 15% for city is achieved.

• Korean Medical Education Review
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• v.17 no.3
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• pp.131-139
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• 2015

The purpose of this study was to develop a career planning program for medical students and to examine its effectiveness with regard to career choice motivation and career maturity. A total of 89 medical students participated in the study. Forty-four were in the experimental group and 45 were in the control group. The collected data were analyzed with the t-test, analysis of covariance, descriptive statistics, and analysis of frequency by PASW SPSS ver. 18.0 (SPSS Inc.). A career planning program was developed using the ADDIE (analysis, design, development, implementation, and evaluation) model. The contents of self-understanding and career exploration were included in this program. The program was conducted as a seminar with preferred major professors. There was a significant difference in the intrinsic motivation score between the control and experimental groups (p<0.05). The score of the experimental group (M=4.59) was higher than that of the control group (M=4.40). Significant differences in decisiveness (p<0.01) and realistic choice (p<0.05), the sub-factors of the career maturity test, were found between the control and experimental groups. The score of decisiveness of the experimental group (M=2.94) was higher than that of the control group (M=2.79). The score of realistic choice in the experimental group (M=3.17) was lower than that in the control group (M=3.37). Most medical students were satisfied with the career planning program. It is hoped that these results provide useful information for designing career guidance programs for students in medical schools.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.5
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• pp.410-418
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• 2018

This paper describes the design, analysis, and verification tests of the Dual-axis X-band antenna pointing mechanism(XAPM) that has been developed for the Earth observation mission at low Earth orbits. Based on the experience of development and operation of the similar system, we defined the main points and requirements of the system design and confirmed the characteristics of the system through the verification test of the launch and orbit environment test of the engineering qualification model. Through the characteristics and verification techniques of the system acquired during this process, improvement points of the later qualification model are derived.