• Fire Science and Engineering
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• v.18 no.4
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• pp.57-63
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• 2004

We investigated heat properties of connection terminal in residual current protective devices(RCD) according to contact pressure for low voltage appliance. And we analyzed voltage and current waveform and oxide propagation when the poor-contact happened between terminal and wire. When contact pressure between terminal and connection wire was not applied, the heat was generated and an oxide was formed on the surface of the wire. The temperature of the insulation surrounding terminal was ascended sharply by poor-contact, micro-sparks and continuous arc sound happened in interior terminal. When the poor-contact by vibration occurred inner conductor of terminal and wire, an oxide was propagated on contact surface and the temperature was increased at 869℃. Thus, we found that the risk of electrical disaster is high in terminal and connection wire parts.

• Journal of the Korean Geotechnical Society
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• v.25 no.4
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• pp.55-68
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• 2009

A new borehole roughness and verticality measurement system (BKS-LRPS) for rock socketed drilled shafts were developed and verified its field application. The stability of BKS-LRPS was verified for several field conditions, which included the effect of measuring unit shaking, the application of water/air calibration factors, and the resistance of high water pressure inside piles. Also, effective measurement distances for various conditions of turbidity were defined in the field by measuring borehole roughness and vertical alignment for 6 drilled shafts. Vertical alignments for all drilled shafts could be measured by BKS-LRPS. However, borehole roughness was not able to be measured due to high turbidity caused by RCD drilling processing. Based on the BKS-LRPS field verification, BKS-LRPS is the first borehole roughness and verticality measurement system applying both in the water and air.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.219-226
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• 2014

Evaluation of tree responses to temperature elevation is critical for a development of forest management techniques coping with climate change. We conducted a study on the growth responses of Betula costata, Fraxinus rhynchophylla, and Quercus variabilis seedlings to open-field artificial warming. Artificial warming set-up using infra-red heater was built in 2012 and the temperature in warmed plots was regulated to be consistently $3^{\circ}C$ higher than that of control plots. The seeds of three species were sown, and the responses of growth, biomass allocation, and net photosynthetic rate of newly-germinated seedlings on the open-field artificial warming were determined. As a result, the growth responses of the seedlings differed with the species. B. costata showed decreases in the height to diameter ratio (H/D ratio), biomass, root weight to shoot weight ratio, and net photosynthetic rate. However, root collar diameter (RCD), height, biomass, and net photosynthetic rate of Q. variabilis were increased, while the response of F. rhynchophylla was rather obscure. There was no significant difference between warmed and control plots in seedling growth for 3 species in July, whereas, RCD, height, and H/D ratio of Q. variabilis were increased and H/D ratio of B. costata was decreased in November under warming. Species-specific growth responses to warming were similar to the species-specific responses of net photosynthetic rate and biomass allocation; therefore, net photosynthetic rate and biomass allocation might attribute to growth responses to warming. Besides, a relatively obvious response in autumn compared to summer might be affected by the phenological change following artificial warming. Species-specific responses of three deciduous species to warming in this study could be applied to the development of adaptive forest management policies to climate change.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.390-399
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• 2020

We investigated the effect of seedling age and planting density on early growth performance of Zelkova serrata trees. Containerized Z. serrata seedlings, 1-year-old and 2-year-old, were planted according to two different planting densities (3,000 and 5,000 trees ha-1) at the end of March, 2017. Three plots were established for each treatment (2 seedling ages × 2 planting densities). We calculated the survival rate (%) of out-planted seedlings as well as the stem volume based on the root collar diameter (RCD) and height (H) in September of each year, from 2017 to 2019. Seedling age and planting density did not affect survival rate of the out-planted trees. Planting density did not affect height of the trees, whereas the treatment significantly affected RCD and the H/D ratio for 2-year-old seedlings in 2019. The stem volume per tree was highest in the plot of 2-year-old seedlings at 5,000 trees ha-1 and lowest in the 1-year-old seedlings at 3,000 trees ha-1. In addition, the tree height in both 1-year-old and 2-year-old Z. serrata trees was greater in the 5,000 trees ha-1 plot than in the 3,000 trees ha-1 plot. There was no interactive effect between seedling age and planting density on stem volume; however, as seedling age and planting density increased, stem volume of Z. serrata trees increased. The values for stem volume per hectare are 85%, 68%, and 300% higher in 1-year-old 5,000 trees ha-1, 2-year-old 3,000 trees ha-1, and 2-year-old 5,000 trees ha-1 plots, respectively, compared to the values in 1-year-old 3,000 trees ha-1. This result shows that high planting density (close planting) affects tree growth differently based on seedling age, and suggests that the planting density of 5,000 trees ha-1 is suitable for 2-year-old seedlings to improve early growth field performance.

• 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.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.357-364
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• 2022

We investigated the early growth characteristics of Quercus rubra planted in six regions (Hwaseong, Yangpyeong, Pyeongchang, Samcheok, Chungju, and Gimje) in South Korea in relation to soil physicochemical properties and meteorological factors. Q. rubra (1-0) were planted at a density of 3,000 trees ha^-1. The average height, root collar diameter (RCD), and volume of 8-year-old Q. rubra planted in 2014 were 3.52 m, 3.84 cm, and 0.0023 m³, respectively. The growth parameters of Q. rubra were the highest and lowest in Hwaseong and Pyeongchang, respectively. Correlation analysis among the soil physicochemical properties, meteorological factors, and plantation growth characteristics found that pH was the only soil factor negatively correlated with RCD, and the other soil factors were not significantly correlated with the growth characteristics. However, growth characteristics were positively correlated to average temperature from March to October and daily maximum temperature; and they were negatively correlated to altitude, topology, and the number of rainy days from March to October. In particular, the trees planted in Hwaseong area showed the best early growth characteristics because this area had the highest daily maximum temperature, the x average temperature from March to October, the low altitude, and it is located close to the foot of a mountain. In Pyeongchang, the early growth characteristics were negatively affected by winter cold damage because of the high altitude, low daily minimum temperature, and damage by wild animals. In Hwaseong, meteorological factors such as temperature and altitude were more highly correlated to growth characteristics of Q. rubra than the physicochemical soil properties. These results will provide useful information for determining suitable sites for Q. rubra plantations and for predicting early growth characteristics in response to environmental factors.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.143-150
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• 1998

The aim of this study was to evaluate domestic enzyme immunoassay(EIA) kit 'LG RCD 3.0' (LG) for the detection of antibody to hepatitis C virus(anti-HCV) in comparision with Axsym HCV version 3.0(Axsym), Cobas Core anti-HCV EIA(Cobas). Cobas kit shows better clear distinction between positive and negative by signal/cutoff ratio(S/C), but it also reveal relatively high false positive rate. The concordance rate of test results between LG and Axsym was 96.2%, between LG and Cobas was 95.5%, and total agreement between three EIA kit was 93.9%. LG were relative poor distinction between positive and negative results, but it could be applied clinically as a screening tool for hepatitis C in general population. The SIC of one false negative result by LG was 0.91, and false positive were less than 4.0, therefore we concluded it is necessary to confirm by immunoblotting assay when SIC were between 0.8 and 4.0.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.146-156
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• 2018

The ship's chart system was changed from the use of paper chart to the ENC (Electronic Navigational Chart) using ECDIS (Electronic Chart Display and Information System). The introduction of ENC in ships is necessary for ship automation and for the digitalizing of data and integration of information, but unexpected various problems have occurred and are posing a great threat to safe navigation in the transitional period when the new system has been applied to the sea. In this paper, to assess whether ECDIS contributes to the safety of navigation for its intended purposes as new navigation equipment, a usability test of ECDIS was conducted on masters and crew who have used ECDIS on ocean-going vessels. The result was verified with a paired sample T-test, and it was significantly analyzed with the effectiveness of a simplified task; cost efficiency was decreased since ECDIS was used. By analyzing 'MSC.1/Circ.1503 ECDIS - Guidance for good practice', we found that the effects of the maintenance of ECDIS software, operating anomalies identified within ECDIS, differences between raster chart display system (RCDS) and ECDIS, and matters of identification were compounded by the overlapping information on the safety of ships. The anomalies were also grouped according to their characteristics, and we proposed suitable improvements accordingly. The reason for the reduction in efficiency in the usability test was that the problems with ECDIS were intended to be solved only with the careful use of navigational officers who did not have systematic solutions. To solve these problems, the maintenance of software, the improvement of ECDIS anomalies, the reliable ENC issuance including the global oceans, and S-mode development are a priority.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.187-191
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• 1998

For efficient and economical production of Btrc,illus tlz~rr.ingi~r1~sstirsa in NT0423 as amicrobial-control agents, a new culture medium and culture condition were developed. Five mediadesignatzd as SWI I , SW14, SW23. SW32 and SW4I were prepared ~ : i t hv arious mixture ratio ofsoybean cake and wheat bran. It was founcl that in terms of the cell growth rate and development ofsporulation of B, thrri.il~girrl.sis strain NT0423 in all SW culture media were more efficient than those inGYS and in LB media. Total cell number in all SW media showed similar values, hut SW32 lnediilm wasthe most efficient in the development of spore, which amo~~ntetod 3.7 x 10XC FUImI. Also. at the pHranging frorn 6.2 to 7.3 in the mediiun~ no ad\:erse effect was not made in the culture of B. thur-ingicnsisstrain NT0423. The optimal volume (%) of SW32 mecliuni in a 5 1 fernientor was determined as 4 8\rolume of total niediuni. resulting ill growth (4.2 x 1OTCFUlrnl) of H. t1~~irir1,yirrz.ssit.vr ain NT0423. As H.t l i ~ t r i t ~ g iw~ a~s~ csuil~tu rcd in the shakc-flash and 5 1 fcrnientor. bacterial cells were yielded to 1 X 10"CFUIml and 5 x I O1oCFLJlml.FUIml and 5 x I O1oCFLJlml.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.1
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• pp.8-19
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• 2020

Objectives : The purpose of this study was to examine whether the MMPI-2-RF serves as a useful tool to differentiate between the subtypes of high risk of suicide among psychiatric outpatients. Methods : Patients were recruited from the department of psychiatry of university hospital. Participants were diagnosed using DSM-5 criteria by board certified psychiatrists. Their medical records were reviewed retrospectively. And participants were put into 4 groups (Suicide ideation, Suicide attempt, Non-suicidal self-injury, and general psychiatric diagnosis as a control group). For statistical comparison, the MANCOVA with gender as a covariate was used. Results : The results indicated that as previous research with non-clinical sample suggested, psychiatric outpatients with high suicide risk also have significantly higher Emotional/Internalizing Dysfunction, Helplessness/Hopelessness, Suicidal/Death Ideation, Demoralization, Cognitive complaints, Cynicism, Dysfunctional negative thoughts than general psychiatric patients group. But group differences within the high suicide risk patients have not been observed. However, suicide attempt group and NSSI group has higher Behavioral/Externalizing Dysfunction, RC4, AGG than general psychiatric patients group. But there was no difference between suicidal idea group and general psychiatric patients group. Conclusions : There was no group difference observed between all three subtypes, which mean the MMPI2-RF may not be the useful diagnostic tool to navigate high suicide risk subtypes. Even though there was no difference observed in the suicide ideation group, suicide attempt group and NSSI group have higher aggression and externalization. So those indexes could serve as a useful marker to investigate riskiness of suicide related symptoms.