• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.3
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• pp.158-165
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• 2003

This study was conducted to reveal the role of meteorological elements on the habitat characteristics and vegetative structure for S. commixta natural populations at Ulleung Island. Potential Evapotranspiration(PET) by elevation of Ulleung Island was estimated using Thornthwaite's climatology estimating method. Also, Warm Index (WI), Coldness Index (CI) and vegetative composition by elevation were determined. The following results were obtained: The S. commixta trees wire mainly distributed from an elevation of 300 m to 900 m. The WI and CI were about 66.8∼95.0, -21.5∼-7.7, respectively. Water deficit by precipitation and Potential Evapotranspiration (PET) mainly occurred from March to October at all elevations. But wafer deficits diminished with increased elevation. The apparent species in S. commixta natural populations at Ulleung Island were: 10 tree layer species, 17 subtree layer species, and 25 species in the shrub layer. In the tree layer, S. commixta was dominant with the highest value of 46.85, then Fagus crenate 13.43, Acer mono and Tilia amurensis 12.41 and 12.03, respectively. In the subtree layer, A. mono was dominant with the highest value of 13.16, then F. crenata 12.68, Acer pseudo-sieboldianum and S. commixta 11.37 and 10.76, respectively. Dominant species and IV values in the shrub layer were Sasa borealis (22.09) and Rhododendron brachycarpum (10.51). The S. commixta natural forests were in a relatively stable rendition because of the even distribution of its various indexes: the species diversity index of Shannon, the evenness index and dominance were 0.6199∼1.1390, 0.6199∼0.8825 and 0.1852∼0.3801, respectively.

• Food Science and Preservation
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• v.16 no.3
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• pp.342-347
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• 2009

We sought to improve the methods for washing fresh raw ginseng. The quality of ginseng surface-washed by different methods was evaluated during storage at 10C and $20^{\circ}C$. The raw ginseng surface-washing method was a full-cone spray-type procedure using water and air. The water for decontamination had an electrolysis value of 80 ppm, also known as electrolysis water $2^{\circ}C$ water and water containing 5 ppm chlorine dioxide, were also used for decontamination. The Hunter color (${\Delta}E$) of ginseng washed with water withan electrolysis value of 80 ppm, or water with 5 ppm chlorine dioxide, was greater than that seen after other washing methods were used. The weight loss after washing with 5 ppm chlorine dioxide water was similar to that seen after washing with $2^{\circ}C$ water or 80 ppm electrolysis water. Reductions in total microorganism levels, and counts of yeasts and molds, assayed 10 days after washing with 5 ppm chlorine dioxide water were greater than seen after use of other sterilization methods. Quality maintenance on storage, at both 10C and 20C, after washing with 80 ppm electrolysis water, was better than that noted after other sterilization methods. The moisture content of washed ginseng was similar under all storage conditions tested.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.566-575
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• 2003

We reviewed our 18-year surgical experience of biventricular repair for double-outlet right ventricle. Material and Method: One hundred twelve consecutive patients (80 males and 32 females) who underwent biventricular repair for double-outlet right ventricle between May 1986 and September 2002 were included. We assessed risk factors for early mortality and reoperation. Reoperation-free survival rate and actual survival rate were analysed. Result: Most common type of ventricular septal defect was subaortic (n=58, 52%) and non-committed type was second most common (n=32, 29%). Four different surgical methods were used: intraventricular baffle repair (n=71 , 63%): right ventricle to pulmonary ariery conduit interposition or REV with left ventricle to aorta baffle repair (n=24, 21 .4%): arierial switch operation with left ventricle to pulmonary artery baffle (n=14, 12.5%): Senning atrial switch operation with left ventricle to pulmonary artery baffle (n=3, 2.7%). Thirty four patients(30%) underwent palliative procedures before definite repair. Twenty three patients (21%) required reoperations. There were 12 (10.7%) early deaths and 4 late deaths. Age younger than 3 months at repair (p=0.003), cardiopulmonary bypass and aortic cross clamp time (p=0.015, p=0.067), type of operation (arterial switch operation) (p <0.001) and type of ventricular septal defect (subpulmonic type) (p=0.002) were revealed as risk factors for early death in univariate analysis, while age under 3 months was the only significant risk factor in multivariate analysis. Patients younger than 1 year of age (p=0.02), pulmonary artery angioplasty at definitive repair (p=0.024), type of ventricular septal defect (non-committed) (p=0.001), type of operation (right ventricle to pulmonary artery conduit interposition and REV operation) (p=0.028, p=0.017) were risk factors for reoperation in univariate analysis but there was no significant risk factor in multivariate analysis. Follow-up was available on 91 survivals with a mean duration of 110.8$\pm$56.4 (2~201) months. 5, 10 and 15 year survival rates were 86.5%, 85% and 85% and reoperation free survival were 85%, 71.5%, 70%. Conclusion: Age under 3 months at repair, subpulmonic ventricular septal defect and arterial switch operation were significant risk factors for early mortality. Patients with non-committed ventricular septal defect and who underwent conduit interposition or REV operation were risk factors for reoperation. With careful attention to chose best timing and surgical approach depending on morphologic characteristics, biventricular repair for double outlet right ventricle can be achieved with good long-term outcome.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.249-255
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• 2023

Korean melon (Cucumis melo L.) is grown mostly in Northeast Asia area, and as a fruit mainly produced in Korea, the yield per unit area continues to improve, but the cultivation method is limited to soil cultivation, so it is necessary to develop hydroponic cultivation technology for scale and labor-saving is needed. As the ratio of NO₃^- increased, the plant height, the leaf length, the leaf width, and the internode length became longer and larger. On the other hand, the SPAD value decreased. The lower the ratio of NO₃^-, the faster the female flower bloom, and there was no difference in fruit maturity between treatments. There was no difference in the shape of fruit according to the ratio of NO₃^-, and the hardness was higher as the ratio of NO₃^- was lower. The total yield from March to July was KM3 5,650 kg/10a and KM1 4,439 kg/10a, 27% higher in KM3 and, in particular, 36% higher in quantity from March to May, when Korean melon prices were high season. Therefore, it was judged that it would be appropriate to supply NO₃^- suitable for hydroponic cultivation of Korean melon, which was formalized in December and produced from spring, at the level of 6.5 to 10 me·L^-1.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.152-161
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• 2023

In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.

• Journal of The Korean Association For Science Education
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• v.23 no.3
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• pp.265-275
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• 2003

The purpose of this study is to investigate the differences of science achievement between female- and male students in different assessment types, expecting the reconsideration of their scientific ability. to accomplish this purpose, the school science achievement score of 1,487 female- and male students in 2000 were analyzed from the perspectives of assessment methods and gender differences, achievement level and gender differences, and gender characteristics in correlation between each assessment type and total science score. The science achievement score in this study includes mi-term and final paper-and-pencil test in two semesters and performance assessment. The results are as follows. First, in the total science achievement score, whereas female students achieved significantly better than male counterparts in the 7th grade, there was no significant difference between two genders in the 8th and 9th grades. Second, as for the close-ended items, all students, regardless of their gender and grade, showed no significant difference. As for the open-ended items, whereas female students achieved significantly better than male counterparts in the 7th grade, there was no significant difference between gender in the 8th and 9th grades. As for the performance assessment, all female students, regardless of their achievement level, achieved significant better than male counterparts, which is very noteworthy. Third, in the uppermost achievement level, there was no significant difference not only in close- and open ended items but also in performance assessment. Fourth, male students' correlation between performance assessment and total science score was relatively higher than female students'. The result of this study, that female students did significantly better than male students in performance assessment, is interesting in that performance assessment is widely accepted as more reliable and valid method in measuring students' various ability than traditional paper-and-pencil test.

• Korean Journal of Food Science and Technology
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• v.50 no.4
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• pp.407-413
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• 2018

The current study reviews the manufacturing characteristics, upon aging, using different distillation methods with Saccharomyces cerevisiae 88-4 isolated from traditional Nuruk. The alcohol content slightly decreased at 180 days of aging period, under the conditions: -60 cmHg, distilling temperature $50^{\circ}C$, head cut 7%, and body cut 30%. The alcohol content decreased by 2.2% at: -50 cmHg, distilling temperature $60^{\circ}C$, head cut 7%, and body cut 30%. From 2-thiobarbituric acid (TBA) analysis, the TBA values were not found to change significantly in most of the alcohols, but increased at conditions of: -60 cmHg, distilling temperature $60^{\circ}C$, head cut 7%, and body cut 50% and -50 cmHg, distilling temperature $50^{\circ}C$, head cut 7%, and body cut 50%, when initial alcohol levels were low. According to n-propanol, iso-butanol, and isoamyl alcohol analysis, with increasing aging period, the n-propanol and isoamyl alcohol content did not change, although that of iso-butanol decreased. The flavor components showed different results based on the aging period. Results of sensory evaluation showed no significant difference based on aging. The sensory evaluation test was continued for 180 days at a condition of: -60 cmHg, distilling temperature $60^{\circ}C$, and body cut 50%, which had the best overall evaluation ($5.8{\pm}0.9$).

• Korean Security Journal
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• no.20
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• pp.339-363
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• 2009

The 9.11 demonstrated that terrorist attack could be more serious problem than the war in our modern life. No countries in the world have evaded being a target for terrorists today. As well as South Korea, the whole world must share attentions and responsibilities for fighting against the terrorism. Since the international terrorist groups have expanded their targets from Western countries to Koreans, civilian hostages are no longer other's affair; it became a serious threat to public. Increased Korean investment, trade, missionary, and travel overseas also expanded activity regions worldwide. It also result increased terrorist threats and possible abduction. The number of kidnapping crisis has increased since the terrorists use it as an effective method of sending a message. Piracy refers to a broad range of violent acts at sea, and has traditionally been regarded as common enemies. Piracy constitutes a great threat to the security of navigation as well as to the safety of vessels and crews. Lessons from hostage issues such as Korean hostage crisis in Somalia and Afghanistan show that it can cause criticism on moral issues if armed rescue missions fail or hostages are killed, so the governments and related corporations try to solve it by paying ransom. Terrorists and use these advantages in order to put a huge pressure on the governments. In this study we will look at essential characteristics and types of hostage abductions and recognition of national safety, lessons and solutions to previous Korean hostage cases in overseas. At the same time, it provides a guidelines of the direction in the fighting against terrorist groups and Piracy.

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.45-56
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• 2023

In stream ecosystem assessment, RIVPACS, which makes a simple but clear evaluation based on macroinvertebrate community, is widely used. In this study, a preliminary study was conducted to develop a RIVPACS-type model suitable for Korean streams nationwide. Reference streams were classified into two types(upstream and downstream), and a prediction model for macroinvertebrates was developed based on each family. A model for upstream was divided into 7 (train): 3 (test), and that for downstream was made using a leave-one-out method. Variables for the models were selected by non-metric multidimensional scaling, and seven variables were chosen, including elevation, slope, annual average temperature, stream width, forest ratio in land use, riffle ratio in hydrological characteristics, and boulder ratio in substrate composition. Stream order classified 3,224 sites as upstream and downstream, and community compositions of sites were predicted. The prediction was conducted for 30 macroinvertebrate families. Expected (E) and observed fauna (O) were compared using an ASPT biotic index, which is computed by dividing the BMWPK score into the number of families in a community. EQR values (i.e. O/E) for ASPT were used to assess stream condition. Lastly, we compared EQR to BMI, an index that is commonly used in the assessment. In the results, the average observed ASPT was 4.82 (±2.04 SD) and the expected one was 6.30 (±0.79 SD), and the expected ASPT was higher than the observed one. In the comparison between EQR and BMI index, EQR generally showed a higher value than the BMI index.

• Korean Journal of Remote Sensing
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• v.40 no.4
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• pp.363-375
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• 2024

Waterbody change detection using satellite images has recently been carried out in various regions in South Korea, utilizing multiple types of sensors. This study utilizes optical satellite images from Landsat and Sentinel-2 based on Google Earth Engine (GEE) to analyze long-term surface water area changes in four monitored small and medium-sized water supply dams and agricultural reservoirs in South Korea. The analysis covers 19 years for the water supply dams and 27 years for the agricultural reservoirs. By employing image analysis methods such as normalized difference water index, Canny Edge Detection, and Otsu'sthresholding for waterbody detection, the study reliably extracted water surface areas, allowing for clear annual changes in waterbodies to be observed. When comparing the time series data of surface water areas derived from satellite images to actual measured water levels, a high correlation coefficient above 0.8 was found for the water supply dams. However, the agricultural reservoirs showed a lower correlation, between 0.5 and 0.7, attributed to the characteristics of agricultural reservoir management and the inadequacy of comparative data rather than the satellite image analysis itself. The analysis also revealed several inconsistencies in the results for smaller reservoirs, indicating the need for further studies on these reservoirs. The changes in surface water area, calculated using GEE, provide valuable spatial information on waterbody changes across the entire watershed, which cannot be identified solely by measuring water levels. This highlights the usefulness of efficiently processing extensive long-term satellite imagery data. Based on these findings, it is expected that future research could apply this method to a larger number of dam reservoirs with varying sizes,shapes, and monitoring statuses, potentially yielding additional insights into different reservoir groups.