• Journal of Environmental Impact Assessment
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• v.27 no.2
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• pp.203-214
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• 2018

The purpose of this study is to estimate the concentrated distribution area of nutria (Myocastor coypus) and potential suitable habitat and to provide useful data for the effective management direction setting. Based on the nationwide distribution data of nutria, the cross-validation value was applied to analyze the distribution density. As a result, the concentrated distribution areas thatrequired preferential elimination is found in 14 administrative areas including Busan Metropolitan City, Daegu Metropolitan City, 11 cities and counties in Gyeongsangnam-do and 1 county in Gyeongsangbuk-do. In the potential suitable habitat estimation using a MaxEnt (Maximum Entropy) model, the possibility of emergency was found in the Nakdong River middle and lower stream area and the Seomjin riverlower stream area and Gahwacheon River area. As for the contribution by variables of a model, it showed DEM, precipitation of driest month, min temperature of coldest month and distance from river had contribution from the highest order. In terms of the relation with the probability of appearance, the probability of emergence was higher than the threshold value in areas with less than 34m of altitude, with $-5.7^{\circ}C{\sim}-0.6^{\circ}C$ of min temperature of the coldest month, with 15-30mm of precipitation of the driest month and with less than 1,373m away from the river. Variables that Altitude, existence of water and wintertemperature affected settlement and expansion of nutria, considering the research results and the physiological and ecological characteristics of nutria. Therefore, it is necessary to reflect them as important variables in the future habitable area detection and expansion estimation modeling. It must be essential to distinguish the concentrated distribution area and the management area of invasive alien species such as nutria and to establish and apply a suitable management strategy to the management site for the permanent control. The results in this study can be used as useful data for a strategic management such as rapid management on the preferential management area and preemptive and preventive management on the possible spreading area.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.105-111
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• 2005

Purpose : Daily Q.A is the important step which must be preceded in a radiation treatment. Specially, radiation output measurement and laser alignment, SSD indicator related to a patient set-up recurrence must be confirmed for a reasonable radiation treatment. Daily Q.A proceeds correctness and a prompt way, and needs an objective measurement basis. Manufacture of the device which can facilitate confirmation of output measurement and appliances check at one time was requested. Materials and Methods : Produced the phantom formal daily check device which can confirm a lot of appliances check (output measurement and laser alignment. field size, SSD indicator) with one time of set up at a time, and measurement observed a linear accelerator (4 machine) for four months and evaluated efficiency. Results : We were able to confirm an laser alignment, field size, SSD indicator check at the same time, and out put measurement was possible with the same set up, so daily Q.A time was reduced, and we were able to confirm an objective basis about each item measurement. As a result of having measured for four months, output measurement within ${\pm}2%$, and measured laser alignment, field size, SSD indicator in range within ${\pm}1mm$. Conclusion : We can enforce output measurement and appliances check conveniently, and time was reduced and was able to raise efficiency of business. We were able to bring a cost reduction by substitution expensive commercialized equipment. Further It is necessary to makes a product as strong and slight materials, and improve convenience of use.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.628-634
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• 2008

In recent years, cross-contamination has become one of the noticeable issues in dental clinic. Two major routes of contamination are the direct-contamination through blood and oral secretion and the indirect-contamination through dental office equipments. Especially, air-contamination through air-floating pollutant in a confined space like hospital, and also contamination through aerosol ejected from high-speed handpiece in a dental office was interested. The purpose of this study was to understand risk of bacterial infection through aerosol from handpiece in a dental office, which will help the practitioner with prevention of contamination during dental treatment. The main findings are as follows. 1. In a comparative test, the group using handpiece has higher bacterial number than the group not using handpiece with significant statistical difference(P<0.01). 2. The group using handpiece with rubber dam has lower bacterial number than the group using handpiecewithout rubber dam with significant statistical difference(P<0.01). 3. Comparing the group using drainage water with the group using distilled water as a handpiece water source results in 22.4 cfu and 17.0 cfu respectively but the difference is no statistically significant(P>0.05). 4. Measuring cfu at 0.5m and 1.5m distance, 0.5m distance showed higher bacterial number with statistical significance(P<0.01). 5. Classification of bacterial types showed the largest bacterial number came from gram-positive micrococcus(73.9%), and gram-negative micrococcus, gram-negative bacillus, and gram-positive bacillus follow in descending order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.693-698
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• 1999

To investigate changes of components in salt-fermented northern sand lance, Ammodytes personatus sauce during fermentation, various chemical properties were examined at 1$\~$3 months intervals during 18 months fermentation. The moisture content decreased slightly, but the content of VBN and crude protein, total nitrogen, amino nitrogen, degree of hydrolysis, and absorbance at 453 nm increased gradually during fermentation. On the other hand, ash content, pH, and salinity showed almost no change. The contents of total nitrogen, amino nitrogen, and degree of hydrolysis increased sharply until 6$\~$8 months fermentation and showed the gentle increment after that, The Hx and uric acid were the most abundant in ATP related compounds, ranging from $83.1\%$ to $92.9\%$, After 18 month of fermentation, sauce was rich in free amino acids, such as glutamic acid, alanine, Iysine, leucine, isoleucine, valine, aspartic acid in that order.

• Journal of Food Hygiene and Safety
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• v.36 no.5
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• pp.447-453
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• 2021

In this study, the effectiveness of physical control technology, a combined light sterilization (LED, UV) and hot water treatment in reducing Aspergillus ochraceus for food production environment was investigated. In brief, 1 mL aliquot of A. ochraceus spore suspension (10^7-8 spore/mL) was inoculated onto stainless steel chips, which was then dried at 37℃, and each was subjected to different physical treatment. Treatments were performed for 0.5, 1, 2, 5, 8, and 11 hours to reduce the strains using a light-emitting diode, but no significant difference was confirmed among the treatments. However, a significant reduction was observed on the chips treated with UV-C exposure and hot water immersion. After being treated solely with 360 kJ/m² of UV-C on stainless steel chip, the fungi were significantly reduced to 1.27 log CFU/cm². Concerning the hot water treatment, the initial inoculum amount of 6.49 log CFU/cm² was entirely killed by immersion in 83℃ water for 5 minutes. Maintaining a high temperature for 5 minutes at the site is difficult. Thus, considering economic feasibility and usability, we attempted to confirm the appropriate A. ochraceus reduction conditions by combining a relatively low temperature of 60℃ and UV rays. With the combined treatments, even in lukewarm water, A. ochraceus decreased significantly through the increases in the immersion time and the amount of UV-C irradiation, and the yield was below the detection limit. Based on these results, if work tools are immersed in 60℃ lukewarm water for 3 minutes and then placed in a UV sterilization device for more than 10 minutes, the possibility of A. ochraceus cross-contamination during work is expected to be reduced.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.100-117
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• 2020

National Treasure no. 101, the stupa of State Preceptor Jigwang from the Beopcheonsa Temple Site in Wonju has been transferred from place to place and reassembled several times since it was built. In particular, overall dismantling and repair was carried out in 1957 to restore parts damaged by bombing during the Korean War. Documented information on the repair process and materials used at that time does not exist. However, various types of metal materials used for this stupa have been identified during conservation work. Besides clamps anchor bolts, 9mm-thick circular rebars were mainly used for joining the parts of this stupa, while circular rebars and wires of various thicknesses were used for joining the parts with mortar restoration materials. Although deformed bars are typically used for stone pagodas classified as architectural structures, smooth circular rebars were used in this case. In terms of restoration using mortar, material shapes were transformed, bound alternately, and twisted irregularly to improve bonding strength and coherence in order to insert restoration materials and to bolster structural weaknesses. In addition, metallographic analysis showed the material to be hypo-eutectoid steel with low carbon content. Many non-metallic inclusions in the shape of drops of different sizes were included, which do not affect the whole elemental composition due to the very small quantities involved. Qualitative and EPMA analysis of Mn and S, which were not identified by SEM-EDS area analysis, established an even distribution of MnS in crystal grains of the microstructure, regardless of the shape of the samples. It is presumed that secondary homogenization and softening might have been conducted after manufacturing to facilitate the working process. Furthermore, in consideration of properties indicating that the thinner the steel is, the less carbon content contained and the greater the elasticity and elongation, it is judged that restoration work was ordered.

• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.54-60
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• 2024

This study investigated the effectiveness of using pathogens and aqueous acids to reduce the Aspergillus ochraceus and Rhodotorula mucilaginosa contamination in livestock production environments. For this study, 1 mL of each bacterial suspension (10⁷-10⁸ spores/mL) was inoculated on a knife surface, dried at 37℃, and used under each treatment condition. First, to investigate the effect of organic acids, acetic, lactic, and citric acids were used. Subsequently, to select the appropriate concentration, they were prepared at concentrations of 0.5, 1, 2, 3, 4, and 5%, respectively. Accordingly, to further maximize the effect of organic acid treatment, we combined the treatment with ultraviolet light. The two strains showed a significant difference (P<0.05) compared to the initial strain, with a greater than 90% decrease in the concentrations of all organic acids. Consequently, acetic and lactic acids decreased by approximately 5 and 2 log colony forming unit (CFU)/cm², respectively, when treated with ultraviolet light (360 mJ/cm²); however, citric acid decreased by less than 1 log CFU/cm². However, when manufactured with 4% acetic acid, a severe malodor was emitted, making it difficult for workers to use it in a production environment. Accordingly, the optimal treatment conditions for organic acid and ultraviolet light for application were selected as follows: immersion in a 4% lactic acid solution for 1 minute and then, sterilization with ultraviolet light at 360 mJ/cm². Finally, when a pork meat sample was cut with a knife that was finally washed with lactic acid and treated with ultraviolet light, the low level of inoculum transferred from the cleaned knife to the surface of the sample was not detected. In conclusion, using this established method can prevent cross-contamination of the surface of the meat during processing.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.349-355
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• 2016

This study was performed to investigate food safety of 18,446 distribution foods in the northern Gyeongii area from 2010 to 2014 year. Food safety analysis was conducted by using Korean food code and food additives code. Fail determination about standards and specifications was 184 cases of 18,446 distribution foods, which represented about 1.00% fail rate of total cases. In the case of collected by food sanitation inspector, fail determination was 124 cases of 13,706 foods and showed about 0.90% fail rate. In the case of requested for food safety inspection, fail determination was 42 cases of 3,419 foods and showed about 1.23% fail rate. Results of fail determination by years, 61 cases (about 1.66%) detected fail among 3,683 foods in 2010 year, 37 cases (about 0.96%) detected fail among 3,863 foods in 2011 year, 44 cases (about 1.18%) detected fail among 3,721 foods in 2012 year, 25 cases (about 0.68%) detected fail among 3,669 foods in 2013 year, and 17 cases (about 0.48%) detected fail among 3,510 foods in 2014 year. In distribution of fail rate by month, september was showed the highest fail rate at 2.54% compared with other months. Fail determination by type of foods showed that 23 cases of perilla oil detected fail in 204 foods (about 11.27%), 32 cases of sesame oil detected fail in 394 foods (about 8.12%), 9 cases of pickles detected fail in 177 foods (about 5.08%), and 10 cases of red pepper powder detected fail in 283 foods (about 3.53%). For analysis of fail determination by examination items, microorganism was 28 fail cases (15.22%) and that was the highest level among examination items, linolenic acid and acid value were 27 fail cases (14.67%), iodine value was 19 fail cases (10.33%), content amount was 16 fail cases (8.70%), and sulfur dioxide was 9 fail cases (4.89%). In conclusion, the result of this study indicate that various fail determination items were detected of distribution foods on the market during the past five years and it was showed to higher hazard occurrence potential due to food. Therefore, more strict food safety control will be need for improving human health by prevent food health problem and ensure food safety.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.774-784
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• 2014

The purpose of this study was to present management guidelines for critical control points by analyzing microbiological hazardous elements through screening Potentially Hazardous Foods (PHF) menus in an effort improve the microbiological quality of foods prepared by restaurant operations. Steamed spinach with seasoning left at room temperature presents a range of risk temperatures which microorganisms could flourish, and it exceeded all microbiological safety limits in our study. On the other hand, steamed spinach with seasoning stored in a refrigerator had Aerobic Plate Counts of $2.86{\pm}0.5{\log}\;CFU/g$ and all other microbiological tests showed that their levels were below the limit. The standard plate counts of raw materials of lettuce and tomato were $4.66{\pm}0.4{\log}\;CFU/g$ and $3.08{\pm}0.4{\log}\;CFU/g$, respectively. Upon washing, the standard plate counts were $3.12{\pm}0.6{\log}\;CFU/g$ and $2.10{\pm}0.3{\log}\;CFU/g$, respectively, but upon washing after chlorination, those were $2.23{\pm}0.3{\log}\;CFU/g$ and $0.72{\pm}0.7{\log}\;CFU/g$, respectively. The standard plate counts of baby greens, radicchio and leek were $6.02{\pm}0.5{\log}\;CFU/g$, $5.76{\pm}0.1{\log}\;CFU/g$ and $6.83{\pm}0.5{\log}\;CFU/g$, respectively. After 5 minutes of chlorination, the standard plate counts were $4.10{\pm}0.6{\log}\;CFU/g$, $5.14{\pm}0.1{\log}\;CFU/g$ and $5.30{\pm}0.3{\log}\;CFU/g$, respectively. After 10 minutes of chlorination treatment, the standard plate counts were $2.58{\pm}0.3{\log}\;CFU/g$, $4.27{\pm}0.6{\log}\;CFU/g$, and $4.18{\pm}0.5{\log}\;CFU/g$, respectively. The microbial levels decreased as the time of chlorination increased. This study showed that the microbiological quality of foods was improved with the proper practices of time-temperature control, sanitization control, seasoning control, and personal and surface sanitization control. It also presents management guidelines for the control of potentially hazardous foods at the critical control points in the process of restaurant operations.