• Smart Structures and Systems
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• v.12 no.3_4
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• pp.415-426
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• 2013

Condition assessment and monitoring of bridges is critical for safe passenger travel, public transportation, and efficient freight. In monitoring, displacement measurement capability is important to keep track of performance of bridge, in part or as whole. One of the most important parts of a bridge is the expansion joint, which accommodates continuous cyclic thermal expansion of the whole bridge. Though expansion joint is critical for bridge performance, its inspection and monitoring has not been considered significantly because the monitoring requires long-term data using cost intensive equipment. Recently, a wireless smart sensor network (WSSN) has drawn significant attention for transportation infrastructure monitoring because of its merits in low cost, easy installation, and versatile on-board computation capability. In this paper, a rapid wireless displacement monitoring system, wireless hybrid sensor (WHS), has been developed to monitor displacement of expansion joints of bridges. The WHS has been calibrated for both static and dynamic displacement measurement in laboratory environment, and deployed on an in-service highway bridge to demonstrate rapid expansion joint monitoring. The test-bed is a continuous steel girder bridge, the Founders Bridge, in East Hartford, Connecticut. Using the WHS system, the static and dynamic displacement of the expansion joint has been measured. The short-term displacement trend in terms of temperature is calculated. With the WHS system, approximately 6% of the time has been spent for installation, and 94% of time for the measurement showing strong potential of the developed system for rapid displacement monitoring.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1485-1494
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• 2023

The bow of the nuclear fuel assembly is a well-known phenomenon. One of the vital criteria during the history of nuclear fuel development has been fuel assembly's mechanical stability. Once present, the fuel assembly bow can lead to safety issues like excessive water gap and power redistribution or even incomplete rod insertion (IRI). The extensive bow can result in assembly handling and loading problems. This is why the fuel assembly's bow is one of the most often controlled geometrical factors during periodic fuel inspections for VVER when compared e.g. to on-site fuel rod gap measurements or other instrumental measurements performed on-site. Our proposed screening method uses existing video records for fuel inspection. We establish video frames normalization and aggregation for the purposes of bow measurement. The whole process is done by digital image processing algorithms which analyze rotations of video frames, extract angles whose source is the fuel set torsion, and reconstruct torsion schema. This approach provides results comparable to the commonly utilized method. We tested this new approach in real operation on 19 fuel assemblies with different campaign numbers and designs, where the average deviation from other methods was less than 2 % on average. Due to the fact, that the method has not yet been validated during full scale measurements of the fuel inspection, the preliminary results stand for that we recommend this method as a complementary part of standard bow measurement procedures to increase measurement robustness, lower time consumption and preserve or increase accuracy. After completed validation it is expected that the proposed method allows standalone fuel assembly bow measurements.

• Fire Science and Engineering
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• v.32 no.6
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• pp.28-33
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• 2018

To measure the full scale fire test and heat release rate of bed mattresses according to the building compartment space, a fire test was performed using the Standard test method to determine the heat release rate of mattresses and mattress sets (KS F ISO 12949: 2011). Both test locations showed similar fire growth until approximately 3 minutes after burner ignition. After 3 minutes, the heat release rate in the test room was higher than the open calorimeter. For bed mattresses (SS), the maximum heat release rate in the open calorimeter was 735 kW and the maximum heat release rate in the test room was 992 kW. For bed mattresses (Q), the heat release rate in the test room increased more rapidly than the open calorimeter. The maximum heat release rate in the open calorimeter was 1,087 kW (346 s) and the maximum heat release rate in the test room was 2,127 kW (287 s). The difference between the maximum heat release rate and the measurement time according to the test location was confirmed.

• Journal of the Korean Home Economics Association
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• v.26 no.3
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• pp.209-224
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• 1988

The purpose of this study is to investigate the relations between spouse's self-disclosure and marital adjustment. A measurement tools used for this study are self-disclosure scale, which was adapted and reproducted from Jourard's Self-Disclosure! Questionnaire(JSDQ), and marital adjustment scale, which was modified and supplemented form Dyadic Adjustment Scale (D.A.S). developed by Spanier. The subjects were 154 married couples dwelling in Seoul and questionnaires are recorded separately by both spouses. Statistical methods such as frequency, percentage, mean, standard deviation, one way ANOVA and pearson correlation were used for data analysis. The results of this study are as follows; 1) For husband, self-disclosure degree was significant difference according to level of education. That is, the more husband was higher level of education, the more husband tended to disclose to wife. 2) Among the variables to have influence on the marital adjustment, level of education and marriage pattern had influence on wive's martial adjustment and family income and marriage pattern had influence on husbands' marital adjustment. 3) Wives were higher disclosed than husbands and wives were more disclosed than perceived husbands' disclosure. 4) There were positive correlation between the self-disclosure of husbands and the marital adjustment of wives. (r+.3872, p<.005) And there were positive correlation between the self-disclosure of wives and the marital adjustment of husbands. (r=.4997, p<.005) 5) For wives, the perception of husbands' disclosure correlates with wives' marital adjustment. (r=.4592, p<.005) For husbands, the perception of wives' disclosure correlates with husbands' marital adjustment.(r=.5610, p<.005) From this results, full and honest self-disclosure is needed for high marital adjustment of a married couple. In the future, a study on the relationship between self-disclosure and marital adjustment is need to various measure of many subject.

• Fire Science and Engineering
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• v.31 no.4
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• pp.71-79
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• 2017

A rack warehouse with a vertically loading type and high loading density has severe risks and damage during its fire. In this regard, US and Japan strive to minimize the fire spread by applying in-rack sprinkler, horizontal barriers, etc. corresponding to their own rack warehouse but there is no study and policy in Korea. Therefore, a model scale fire test was carried out targeting the standard rack incorporating the national rack warehouse in order to check fire characteristics in ignition points and installation distances of horizontal barriers in this study. As a result of the test, vertical fire spread of about 30% was inhibited by narrowing its installation distance from 2-layer to 1-layer in an ignition condition of the flue space. In addition, as a result of the measurement of the temperature in the upper and lower parts of the horizontal barrier, the temperature distribution showed about 2~4 higher in a condition with an installation of the barrier than that in the condition without the barrier. Consequently, it is likely that the horizontal barrier will help the initial operation of in-rack sprinkler.

• Food Engineering Progress
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• v.13 no.4
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• pp.302-307
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• 2009

In this study, four Korean black raspberry wines were developed from different regions in Korea; Gochang (G), Heongsung (H), Jeongup (J), and Sungchang (S). Their flavor profiles were determined using a combination of volatile analysis and sensory evaluation. From the volatile analysis of the developed wines, 8 acids, 17 alcohols, 12 esters, 9 terpenes, 3 aldehydes and ketones, and 4 miscellaneous compounds were identified. Preferences of appearance, aroma, full-body, and overall acceptability in the developed wines were determined using 9-point hedonic scale by 43 panelists, compared with one commercial black raspberry wine (Sunw). The sweetness, sourness, astringency levels were also evaluated using 9-point just-about-right (JAR) scale. The mean overall acceptability score of Sunw (5.58) was the highest among the tested wines, followed by G (4.81), S (4.44), H (4.41), and J (4.13) (p<0.05). Sweetness levels in the developed wines were overall lower than JAR level, while sourness and astringency levels were overall higher than JAR level.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.222-230
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• 2023

In the present work, the scale effect on the Boil-Off Rate (BOR) was investigated based on an analytical method to systematically evaluate the thermal performance of a Liquefied Natural Gas (LNG) Cargo Containment System (CCS). A two-dimensional thermal resistance network model was developed to accurately estimate the heat ingress into the CCS from the outside. The analysis was performed for the KC-1 LNG membrane tank under the IGC and USCG design conditions. The ballast compartment of both the LNG tank and cofferdam was divided into six sections and a thermal resistance network model was made for each section. To check the validity of the developed model, the analysis results were compared with those from existing literature. It was shown that the BOR values under the IGC and USCG design conditions were agreed well with previous numerical results with a maximum error of 1.03% and 0.60%, respectively. A SDR, the scale factor of the LNG CCS was introduced and the BOR, air temperature of the ballast compartment, and the surface temperature of the inner hull were obtained to examine the influence of the SDR on the thermal performance. Finally, a correlation for the BOR was proposed, which could be expressed as a simple formula inversely proportional to the SDR. The proposed correlation could be utilized for predicting the BOR of a full-scale LNG tank based on the BOR measurement data of lab-scale model tanks.

• Korean Journal of Culture and Social Issue
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• v.29 no.4
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• pp.429-453
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• 2023

Due to recent demographic changes, employees from diverse generations now work together in organizations. Thus, there is a need for research on intergenerational cooperation. However, the lack of valid and reliable measures to capture intergenerational climate in the workplace is an obstacle to research. Therefore, we translated the Workplace Intergenerational Climate Scale(WICS) into Korean and validated it with a sample of 1,052 Korean full-time employees. Firstly, we conducted an exploratory factor analysis by using sample 1(N = 460) and revealed a five-factor solution. Secondly, the confirmatory factor analysis(sample 2; N = 592) showed a good model fit of the correlated five-factor model. Thirdly, the scale's discriminant and convergent validity was supported by negative correlations with four types of existing ageism scales and by positive correlations with trust, organizational commitment, work engagement, psychological safety, intention to remain, job satisfaction, and communication satisfaction. Moreover, it further demonstrated significant incremental validity in predicting positive outcome variables even when controlling for pre-existing agism scales. Lastly, we confirmed strict measurement invariance of the scale between the age groups(below 40 versus above 40). The findings support the reliability and validity of the Korean version of WICS among Korean employees. The scale will be broadly applied to measure intergenerational climate of organizations and provide practical implications for HR management.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.27 no.1
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• pp.39-47
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• 2016

Objectives: The aim of this study was to examine the association between current suicidal or violent behavior and deficits of specific neurocognitive variables in child and adolescent inpatient samples diagnosed with mood disorder. Methods: A retrospective review of the charts of mood disorder patients hospitalized at Samsung Medical Center between April 2004 and April 2015 was conducted. Child and adolescent patients aged between 10 and 18 years old and those who finished neurocognitive function testing during their hospitalization were included. Among them patients whose full scale IQ was between 85 and 115 were selected (N=111). Participants were first divided into two age-groups-group Y ($10{\leq}age{\leq}15$, N=54) and group O ($16{\leq}age{\leq}18$, N=57)-because neurocognitive function test tools were different according to age [Wechsler Intelligence Scale for Children (WISC) for 10 to 15-year-old patients, Wechsler Adult Intelligence Scale (WAIS) for 16 to 18-year-old patients]. They were then divided according to their suicidal or violent behavior-non suicidal/violent group (NG), suicidal group (SG), violent group (VG), and both suicidal/violent group (BG). The Child Behavior Checklist (CBCL) was checked for measurement of participants' behavior and the Gordon Diagnostic System was checked for measurement of their attention efficiency. Kruskal-Wallis Test and Tukey test was used to determine the differences in neurocognitive function between groups. Results: O-SG patients showed lower scores on the comprehension subscale of WAIS-III than O-NG patients (${\chi}^2=8.454$, p=.015). O-VG patients showed lower scores on the block design subscales of WAIS than O-SG patients (${\chi}^2=7.496$, p=.024). Y-VG patients showed higher scores in aggressive behavior, externalizing problems, and total problems scores of CBCL. Conclusion: This study showed relationship between specific neurocognitive deficits and suicidal or violent behavior. These relationships were significant in relatively older adolescents.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.421-424
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• 2009

사장교 케이블의 감쇠비를 추정하기 위하여 실교량 계측을 수행하였다. 사장교 케이블은 감쇠비가 낮고, 고유 진동수가 케이블의 길이에 따라 넓은 범위에 걸쳐 분포하므로, 바람이나 지점 가진에 의하여 과도한 진동이 발생될 수 있다. 케이블 진동 현상의 원인과 발생되고 진행되는 구조는 다양하나, 진동 현상의 가장 중요한 요소는 감쇠비이며, 케이블 진동의 과도한 진동을 감소시키기 위하여, 케이블의 감쇠비를 증가시키는 방법이 널리 사용되고 있다. 사장교 케이블의 다양한 진동 현상에 대한 발생 여부를 판단하고, 케이블 댐퍼와 같은 여러 제진 대책을 설계하고, 설치된 케이블 제진 대책의 성능을 검증하기 위해서는, 케이블의 감쇠비를 추정하는 것이 매우 중요하다. 일반적으로 사용되어져 온 케이블의 감쇠비 추정 방법은 정해진 모드로 자유 진동을 발생시킨 후, 진폭의 감소 추세로부터 Logarithmic Decrement를 계산하여 감쇠비를 구하는 방법이다. 그러나 수백m에 이르는 긴 케이블에서 정해진 모드의 자유 진동을 발생시키는 것은 쉽지 않다. 최근에는 상시 진동으로부터 감쇠비를 추정하는 여러 기법들이 개발되어져 왔으며, Frequency Domain Decomposition Method나 Stochastic Subspace Identification Method 등이 많이 사용되고 있다. 이 논문에서는, 상시진동 기반의 기법들을 사용하여, 사장교 케이블의 감쇠비를 추정하였으며, 추정된 감쇠비의 신뢰도를 높이기 위해, 측정시간을 늘리고, 가진 풍하중의 영향을 반영하여 보정하였다. 또한 추정된 감쇠비를 Buffeting 진동과 와류 진동과 같이 진동 현상과 진폭별로 분석하였다.