• Korean Journal of Remote Sensing
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• v.23 no.4
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• pp.323-334
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• 2007

We analyzed the ocean environmental data from water sample and automatic measurement instruments with the Incheon-Jeju passenger ship for 18 times during 4 years from 2001 to 2004. The objectives of this study are to monitor the spatial and temporal variations of ocean environmental parameters in coastal waters of the Yellow Sea using water sample analysis, and to compare and analyze the reliability of automatic measurement sensors for chlorophyll and turbidity using in situ measurements. The chlorophyll concentration showed the ranges between 0.1 to $6.0mg/m^3$. High concentrations occurred in the Gyeonggi Bay through all the cruises. The maximum value of chlorophyll concentration was $16.5mg/m^3$ in this area during September 2004. The absorption coefficients of dissolve organic matter at 400 nm showed below $0.5m^{-1}$ except those in August 2001 During 2002-2003, it did not distinctly change the seasonal variations with the ranges 0.1 to $0.4m^{-1}$. In the case of suspended sediment (SS) concentration, most of the area showed below $20g/m^3$ through all seasons except the Gyeonggi Bay and around Mokpo area. In general SS concentration of autumn and winter season was higher than that of summer. The central area of the Yellow Sea appeared to have lower value $10g/m^3$. The YSI fluorometer for chlorophyll concentration had a very low reliability and turbidity sensor had a $R^2$ value of 0.77 through the 4 times measurements comparing with water sampling method. For the automatic measurement using instruments for chlorphlyll and suspended sediment concentration, McVan and Choses sensor was greater than YSI multisensor. The SeaWiFS SS distribution map was well spatially matched with in situ measurement, however, there was a little difference in quantitative concentration.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.230-236
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• 2021

Changes in greenhouse temperature and solar radiation due to fogging and shading were monitored during hydroponics in high temperature in summer season. Experiment 1 consists of four treatments, namely, Control, Shading, Fogging, and Fogging + Shading based on sunny days August. For Experiment 2, two melon cultivars of 'Dalgona' and 'Sopoong gaza' were cultivated in summer of 2020 using Fogging + Shading with the best result for temperature reduction effect from Experiment 1. As a result of Experiment 1, the effect of Fogging + Shading on temperature reduction was apparent where the inside was about 4℃ (as the lowest temperature) lower than the outside. Fogging + Shading showed the inside was 2-4℃ lower than the outside, and Fogging or Shading treatments had little difference, compared to the Control where the internal temperature of greenhouse was 3-4℃ higher than the external. For solar radiation changes between greenhouse inside and outside, the internal change was in a similar pattern between Fogging and Control, and between Shading and Fogging + Shading, respectively. In case of the Fogging treatment (similar with the Control) only the effect of solar radiation reduction as influenced by plastic greenhouse covering materials was examined. The Fogging + Shading had a very similar change in solar radiation to the Shading. Based on these results, Experiment 2 was conducted in summer of 2020 and resulted in a temperature reduction effect of about 3.9℃ according as the inside of air-conditioned greenhouse was kept 32.4℃ when the maximum temperature of the outside reached 36.3℃ in August during the cultivation period. In addition, the quality of melon fruit was good (1.3-1.5 kg of fruit weight, 12.6-13.3 of soluble solids content. In the case of using Fogging + Shading cooling treatment, it can bring about the effect of reducing the temperature during the high temperature in summer, and normal growth of melon and fruit harvesting were possible.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.497-504
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• 2018

Purpose : The purpose of this study was to investigate the temperature changes of the ocular surface before and after cataract surgery using thermography of a thermal imaging camera. Methods : The study included 75 patients (75 eyes) aged from 50 to 79 years who underwent cataract surgery. In the past, those who underwent corneal-related surgery, wearing contact lens, disorder of tear secretion and taking medication for systemic disease were excluded from this study. The temperature changes of the eyeball surface were measured using a thermal imager (Cox CX series, Answer, Korea) following Tear Break Up Time (TBUT) test, Mcmonnies questionnaire and Schirmer's Test in real time, Results : While the temperature of preoperative ocular surface was $35.20{\pm}0.54^{\circ}C$ and that of postoperative temperature was $35.30{\pm}0.53^{\circ}C$, the difference was not significant. The temperature changes in the ocular surface were statistically significant at $-0.12{\pm}0.08{\Delta}$ ($^{\circ}C/sec$) before the surgery and $-0.18{\pm}0.07{\Delta}$ ($^{\circ}C/sec$) after the surgery. In comparison of the age groups, it was shown that the changes in the surface temperature before the surgery were from $-0.19{\pm}0.05{\Delta}$ ($^{\circ}C/sec$) to $-0.14{\pm}0.09{\Delta}$ ($^{\circ}C/sec$) in the 50s group, and from $-0.12{\pm}0.08{\Delta}$ ($^{\circ}C/sec$) to $-0.15{\pm}0.07{\Delta}$ ($^{\circ}C/sec$) in 60s group, and $-0.18{\pm}0.07{\Delta}$ ($^{\circ}C$) to $-0.12{\pm}0.08{\Delta}/sec$) in the 70s group, showing significant changes in the ocular surface temperature at all ages. Conclusion : Following the cataract surgery, all the indicators of dry eye syndrome were decreased, and eye surface temperature changes were significant. The thermography technique of the ocular surface would be expected to be useful for the evaluation of various dry eye syndromes because it is easy to evaluate dry eye syndrome noninvasively and can be quantified.

• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.531-546
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• 2018

Air quality forecasting system with Asian dust emissions was developed in East Asia, and $PM_{10}$ forecasting performance of chemical transport model with Asian dust emissions was validated and evaluated. The chemical transport model (CTM) with Asian dust emission was found to supplement $PM_{10}$ concentrations that had been under-estimated in China regions and improved statistics for performance of CTM, although the model were overestimated during some periods in China. In Korea, the prediction model adequately simulated inflow of Asian dust events on February 22~24 and March 16~17, but the model is found to be overestimated during no Asian dust event periods on April. However, the model supplemented $PM_{10}$ concentrations, which was underestimated in most regions in Korea and the statistics for performance of the models were improved. The $PM_{10}$ forecasting performance of air quality forecasting model with Asian dust emissions tends to improve POD (Probability of Detection) compared to basic model without Asian dust emissions, but A (Accuracy) has shown similar or decreased, and FAR (False Alarms) have increased during 2017.Therefore, the developed air quality forecasting model with Asian dust emission was not proposed as a representative $PM_{10}$ forecast model in South Korea.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.2
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• pp.143-154
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• 2020

Objectives : The purpose of this study was to examine cognitive and psychological characteristics of patients with military service suitability issues compared to the general psychiatric outpatients. Methods : 108 patients who visited psychiatric clinic center due to military service suitability issues and 80 general psychiatric patients were recruited from the Department of Psychiatry of university hospital. ANCOVA and chi-equare test were used to examine differences between two groups. Furthermore, we utilized paired t-test to compare the scrore within military group depending on when they performed the psychological assessment. Results : There were no significant differences between military group and general outpatient group in WAIS-IV scores. However, military group scored remarkably higher than control group on validity scales, F-r and Fp-r whereas they scored lower on validity scale, K-r. Furthermore, military group showed significantly higher on BDI and MMPI-2-RF, EID, RCd, RC2, RC3, COG, HLP, SFD, NFC, STW, SAVE, SHY, DSF, NEGE-r, INTR-r. As a result of comparison within the military group following the periods of assessment, military group did not show the significant differences on the overall scales of MMPI-2-RF. Conclusions : The present study showed that military group tends to report their psychological distress more exaggeratedly. In addition, they had significantly elevated not only emotional distress such as depression and anxiety but interpersonal problem. The implications and limitations were discussed along with some suggestions for the future studies.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.334-342
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• 2022

To meet the needs of Muslim consumers, sausages were prepared using Halal-certified chicken thighs and different amounts of biji powder (0, 20, 30, 40, and 50%), and then the properties of the sausages were compared. As the biji powder levels increased, both the moisture content and the pH of the sausages significantly decreased, whereas their fiber content increased. As the biji powder levels increased, the free radical scavenging effect (DPPH, ABTS) and water holding capacity also increased, and the textural properties also improved. When Muslim consumers evaluated the sensory attributes of the sausages prepared in this experiment and those currently on the market, the ones prepared in this experiment were preferred over the market products. Based on the above results, chicken sausage for Muslim consumers could be successfully produced, and their overall quality and antioxidant effects could be improved by the addition of biji powder (up to 30%).

• Korean Journal of Culture and Social Issue
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• v.26 no.2
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• pp.47-68
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• 2020

Since the early 2000s, Korea has continued to increase the proportion of the elderly population due to low fertility and increased life expectancy. As a result, Korea has now entered the aging society. Because of this demographic change, proportion of active elderly have increased, and many academics, such as sociology, economics, and psychology, have conducted various studies on the active elderly. This study focused on active elderly based on the activity theory of old age and the positive effect of small community participation activity on the elderly. The purpose of this study is to examine whether active elderly' participation in everyday activities, small community participation of the elderly affect citizen participation actively in society as a citizen, and in the process, mediates the effect of small community cohesion and the moderating effect of small community selfishness. This study performed a stepwise regression analysis and a hierarchical regression analysis of 700 elderly people who are participated actively in various small communities. As a result, the partial mediating effect of small community cohesion was shown in the relationship between participation in everyday activities and citizen participation, and the moderating effect of small community selfishness was also shown. These findings suggest that government and interested parties need to develop and implement policies for the small community participation of elderly citizens in consideration of their small community activities, small community cohesion and small community egoism.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.spc
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• pp.30-36
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• 2022

A sensor is needed to continuously and automatically measure the change in HNS concentration in industrial facilities that directly discharge to the sea after water treatment. The basic function of the sensor is to be able to detect ppb levels even at room temperature. Therefore, a method for increasing the sensitivity of the existing sensor is proposed. First, a method for increasing the conductivity of a film using a conductive carbon-based additive in a nanoparticle thin film and a method for increasing ion adsorption on the surface using a catalyst metal were studied.. To improve conductivity, carbon black was selected as an additive in the film using ITO nanoparticles, and the performance change of the sensor according to the content of the additive was observed. As a result, the change in resistance and response time due to the increase in conductivity at a CB content of 5 wt% could be observed, and notably, the lower limit of detection was lowered to about 250 ppb in an experiment with organic solvents. In addition, to increase the degree of ion adsorption in the liquid, an experiment was conducted using a sample in which a surface catalyst layer was formed by sputtering Au. Notably, the response of the sensor increased by more than 20% and the average lower limit of detection was lowered to 61 ppm. This result confirmed that the chemical resistance sensor using metal oxide nanoparticles could detect HNS of several tens of ppb even at room temperature.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.3
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• pp.189-197
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• 2023

Purpose. This study aimed to compare and evaluate the shear bond strength between various temporary prostheses resin blocks fabricated by subtractive and additive manufacturing methods bonded to self-curing reline resin. Materials and methods. The experimental groups were divided into 4 groups according to the manufacturing methods of the resin block specimens and each specimen was fabricated by subtractive manufacturing (SM), additive manufacturing stereolithography apparatus manufacturing (AMS), additive manufacturing digital light processing manufacturing (AMD) and conventional self-curing (CON). To bond the resin block specimens and self-curing resin, the reline resin was injected and polymerized into the same location of each resin block using a silicone mold. The shear bond strength was measured using a universal testing machine, and the surface of the adhesive interface was examined by scanning electron microscopy. To compare between groups, one-way ANOVA was done followed by Tukey post hoc test (α = 0.05). Results. The shear bond strength showed higher values in the order of CON, SM, AMS, and AMD group. There were significant differences between CON and AMS groups, as well as between CON and AMD groups. but there were no significant differences between CON and SM groups (P > .05). There were significant differences between SM and AMD groups, but there were no significant differences between SM and AMS groups. The AMS group was significantly different from the AMD group (P < .001). The most frequent failure mode was mixed failures in CON and AMS groups, and adhesive failures in SM and AMD groups. Conclusion. The shear bond strength of SM group showed lower but not significant bond strength compared to the CON group. The additive manufacturing method groups (AMS and AMD) showed significantly lower bond strength than the CON group, with the AMD group the lowest. There was also a significant difference between the AMD and SM group.

• Korean Journal of School Psychology
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• v.8 no.2
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• pp.133-152
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• 2011

This is a short-term longitudinal study investigating the relationships between changes in mental health and academic burnout among Korean middle school students. Study sample consisted of 409 middle school students in Seoul provision, with 161 male, 216 female, and 32 unidentified. Both Symptom Check List(SCL-47) and Maslach Burnout Inventory-Student Survey(MBI-SS) were used. In order to examine the pattern of changes in mental health and academic burnout among students, standardized residuals were calculated using regression equations which were then put into canonical correlation analysis. The results of this study are as follows. First, according to Function 1, among sub-factors of mental health, decreases in depression, compulsion, anxiety, and hostility were particularly associated with decreases in exhaustion and cynicism among academic burnout. Put in another way, students who showed increases in depression, compulsion, anxiety, and hostility experienced more academic exhaustion and cynicism. Second, according to Function 2, increases in phobic anxiety, compulsion with decreases in anxiety, depression were associated with decrease in academic exhaustion and increase in cynicism. Considering Russell's dimensional theory of emotion, Function 1 showed that mental health symptoms including both aroused and non-aroused affects were related with increases in exhaustion and cynicism while Function 2 showed that mental health symptoms including only aroused aspects were related with decrease in exhaustion and increase in cynicism. Thus, a conclusive intervention program seems to be required to deal with both aroused and non-aroused affects of students who are experiencing increased exhaustion and cynicism. On the other hand, an intervention program focused on aroused affects seems appropriate to students who are experiencing decreased exhaustion and increased cynicism. This study has its value in that it has enhanced understanding of students in school and counseling settings by revealing the relationships between mental health and academic burnout among adolescents and suggested differentiated intervention strategies based on patterns of students' academic burnout.