• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.405-414
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• 2021

Purpose. This study was conducted to evaluate clinical usefulness by evaluating the marginal bone resorption and survival rate of an implant with a taper straight type SLA surface domestically available on the market recently. Materials and methods. 40 implants satisfying the including criteria were observed for one year of 125 implants of 83 adult men and women who had KISPLANT^® implanted from August 2016 to December 2019 at the Department of Periodontology, Chonnam National University Dental Hospital. The marginal bone level was measured on periapical radiographs taken initially and 1 year later and we analyzed implant survival and success rates. A t-test was used for the analysis of the association between the marginal bone resorption and the severity of periodontitis, supportive periodontal therapy, the inserted site, the cause of extraction, immediate placement, and systemic disease. Results. After 1 year of loading, the mesial bone resorption was 0.74 ± 1.07 mm, and the distal bone resorption was 0.53 ± 1.04 mm. The marginal bone resorption of 2 mm or more occurred at 3 implants out of 40 implants after 1 year, so the success rate of implant was 92.5% and survival rate was 100%. There was a significant difference in mesial marginal bone resorption according to the inserted site and no significant differences were found between marginal bone resorption and the other factors. Conclusion. As a result of marginal bone resorption, success rate, and survival rate in this study, we found little marginal bone resorption and high survival and success rate. It can be concluded that they represent excellent clinical results.

• Journal of Korean Society of Disaster and Security
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• v.14 no.4
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• pp.29-36
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• 2021

Recently, due to climate change, the slope is increasing, and the risk of steep slope disasters such as the occurrence of slope collapse in the east coast and Busan region in 2019 and the Gokseong landslide in 2020 is increasing. Particularly, most national parks are made up of mountainous areas, and the risk of disasters on steep slopes is increasing. As the ground of the national park is aging and the weathering and jointing of the bedrock are accelerating due to climate change, the slope collapse and rockfall are increasing, and the annual number of visitors is increasing, it is necessary to manage steep slopes adjacent to multi-use facilities with many users. In this study, dangerous steep slopes that affect multi-use facilities in national parks were analyzed using GIS and verified through field surveys. As a process for extracting steep slopes adjacent to multi-use facilities in national parks, the slope was made in DEM and slopes of 34 degrees or higher were extracted. The difference between the maximum and minimum heights of the extracted slopes was used to confirm that the slopes met the standard for steep slopes, and the analysis of the slope direction was used to confirm whether it had an effect on the multi-use facilities. After that, precision aerial images and field photos were analyzed to finally identify risks at 4 sites, and field surveys were conducted. As a result of the field survey, all 4 sites were found to be steep slopes, 3 were graded D and 1 was graded C, so it was confirmed that management was required as a risk of collapse. All steep slopes extracted through GIS were found to be dangerous, so it is judged that the extraction of steep slopes through GIS would be appropriate.

• Korean journal of aerospace and environmental medicine
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• v.31 no.3
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• pp.77-81
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• 2021

Purpose: The United States of America have pre-migration screening program are mandated through legislation. The one of purpose of this program is to prevent the importation of certain communicable diseases. Examinations of migration applicants are performed by panel physicians who are licensed physicians in the countries of origin that have agreements with the government departments of the country of destination to undertake this activity. In recent decades, the number of US migrants has increased, however COVID-19 impacted this trend of international migrants. The Aim of this study is to examine trends of US applicants and outcomes of tuberculosis and sexual transmitted infections (STIs) screening in South Korean applicants for US visa. Methods: A total of 4,442 applicants participated in US visa health check-up in 2016 to 2020. Results: The numbers of applicant for US visa in males and females was 1,814 and 2,628. The positive results in tuberculosis and STIs screening was noted with 0.66% in nontuberculous mycobacteria (NTM), 0.03% in tuberculosis, 0.03% in gonorrhea, 0.08% in syphilis, and 0.74% in chlamydia. The age groups of 2 to 14 years showed higher positive rate (13.89%) in tuberculin skin test (TST) tests compared to the rate of interferon gamma release assay (IGRA) tests (0.44%, P<0.001). The positive ratio of NTM and abnormal chest X-ray (CXR) which required sputum tests among the applicants over 15 years old has trends to increase with age. The age groups of over 70 years showed high positive rate in NTM and abnormal CXR (4.10%, 20.51%). However, ages 15 to 49 years groups showed 0.00% to 0.30% in NTM and 1.08% to 3.91% in abnormal CXR. In the study population, the positive rates of STIs were 0.03%, 0.08%, and 0.74% in gonorrhea, syphilis, and chlamydia, respectively. Among the participants who underwent sputum smears and cultures were just 1 case of active tuberculosis (0.03%) and 25 cases of NTM infection (0.66%). Conclusion: This study found that rate of positivity in tuberculosis and STIs screening among South Korean applicants for US visa in 2016 to 2020. Regarding tuberculosis, the positivity of CXR among the aged 15 to 59 years applicants was lower than that among over 60 years old. Among 2 to 14 years, positivity of IGRA was very low. And IGRA test can reduce effort of further evaluation compared to TST test in South Korea, so IGRA test among young adults can be useful. High positive rates in STI among young adult could result in high active sexuality, especially chlamydia infection is most common. Therefore Chlamydia polymerase chain reaction should be considered formal protocol among the Korean applicant for US visa.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1216-1221
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• 2012

This study is aimed to investigate microbiological contamination of Angelica gigas Nakai. A total of 111 samples including root, soil, and irrigation water were collected from farms and market to detect aerobic bacteria, Bacillus cereus, coliform, Escherichia coli, Listeria monocytogenes,. Salmonella spp., and Staphylococcus aureus. The contaminations of aerobic bacteria, coliform, and Bacillus cereus in the root during cultivation were found 6.71 log CFU $g^{-1}$, 4.13 log CFU $g^{-1}$, and 3.54 log CFU $g^{-1}$, respectively. The contamination of coliform and B. cereus were detected in all steps from harvesting to processing, with the highest count recorded from the cutting step. In marketing, the contaminations of aerobic bacterial, coliform, and B. cereus were 5.5~6.0 log CFU $g^{-1}$, 2.4~2.6 log CFU $g^{-1}$, and 3.5~4.0 log CFU $g^{-1}$, respectively. Listeria monocytogenes, Salmonella spp, and Staphylococcus aureus were not detected in any of samples. This result indicated that hygienic soil management and post harvest management should be performed to reduce the contamination of hazard microorganisms and to produce safe agro-products.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3037-3047
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• 2012

This study is the investigation research to look into rest, computer work environment and muscle and bone symptom of high school students in some area. With high school students in K area as the object the questionnaires of self-writing type were distributed and the final 685 copies were collected and material analysis was carried out. In the differences between work posture and environment evaluation score following whether or not of pain existing of the each part of pain, the score of the persons who do not have pain was significantly higher than the score of the persons who have pain. The negative correlation between the part of pain and work environment was in desk(shoulder), chair(neck, shoulder, back, and ankle/foot), monitor(shoulder, back) keyboard (neck, shoulder, and ankle/foot) appeared as the result. Controling monitor and chair environment is help to alleviate neck pain and ankle/foot pain respectively. Therefore, computer work environment and bone and muscle symptom have relations and as the use of computer increases, prevention program which can relieve muscle and bone symptom by improving computer work environment is necessary.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.476-482
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• 2006

An experimental study has been performed to investigate the characteristics of air-side heat transfer and friction of a fined tube heat exchanger under heating conditions. Air enthalpy calorimeter was used to obtain the performance evaluation and analysis of the fined tube heat exchanger. Eight finned tube heat exchangers with slit fin, louver fin, and plain fin were used. The air-side heat transfer coefficient was calculated by the log-mean-temperature-difference. Air-side heat transfer and friction were presented in terms of j factor and friction factor on Reynolds number. From the experimental result, it was found that the variations of air-side heat transfer and friction of fined tube heat exchanger with the change of the fin configuration, row number, fin pitch, and tube circuit were obtained. j factor and friction factor decreased with Reynolds number increased. The tube circuit affected the air-side heat transfer and friction. In the case of slit and louver fin, j factor of 1st row was higher than that of 2nd row. But, with increasing Re, j factor was reversed. The characteristics of j factor and friction factor of 2nd row heat exchanger were different according to the kind of fins.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.16-23
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• 1986

Physico-chemical and sensory characteristics of 28 black tea samples prepared by oaring the mixing ratio of 1 kind of Korean and 9 kinds of foreign black tea were determined, and their relationship was statistically analysed. Korean black tea was found to be lower in bulk density, caffeine, theobromine, crude protein, theaflavin, thearubigin and soluble solids, and higher in Hunter L- and b- value, neutral detergent fiber, calcium and ratio of oxidized matter as compared with foreign black tea. The palatability for 8 kinds of foreign black tea was generally increased by mixing with Korean black tea. The number of black tea whose palatability were higher than that of Korean black tea was 12, which was mostly mixed black tea. Theaflavin. Hunter a-value, soluble solids of the tea infusion, and potassium of the manufactured tea were the major guiding characteristics as a result of stepwise multiple regression analysis, and about 67% of the total variations in the palatability of black tea could be explained by the regression equation formulated by the preceding 4 characteristics.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.12-20
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• 2015

The public employers are faced the mounting importance of decision process to settle the optimum VE delivery system of such public facilities buildings and etc. The elements of decision process of the public employer are formed in the various relationships of the concerned and when the projects are coming into effect, the decision process in the VE delivery method and the selection of contractor will be the name of the game. The decision process in the VE delivery method and the selection of contractor are created a case to be one and the same as well as initiates a consistency for the performance. However, the function and role of the public employer are projective accordingly to the organization of employer and the employer especially no system is equal to the capability of perfect evaluation and verification of the ability of the employer. Especially the lowest bidder policy that started with justification to increase the competitiveness and technical capability of the contractors through the completion in between contractors has been providing the hotbed for insolvency, irregularity and irrationality as a result. From this point of view it is declared that the buildup the edifice of supporting system in the process of decision to recover the mutual trust and respect of the concerned in the VE delivery system with the technostress and the systematization based on drawing the elements which affect the decision process of public employer.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.367-371
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• 2000

In order to study the tenderizing effect of proteolytic enzymes in fruits, beef(M. semimembranosus) was marinated with meat sauce containing each fruit juices. After cooking, the shear force was measured by Rheometer and evaluated the sensory properties of beef by quantitative descriptive analysis method. The results are as follows: 1. The combination ratio of meat sauce:water was 2:1 with pH 5.0∼5.5 showed the max. tenderness. 2. As a result of shear force test, the decrease of shear force was pineapple>papaya>fig>kiwifruit>pear: especially, pineapple, papaya and fig tendered the beef significantly comparing with pear and kiwifruit at p<0.001. 3. The tendering effect of pineapple and papaya on the meat showed significant difference (p<0.01) comparing with pear in tenderness and overall acceptability by sensory evaluation; and there was a significant difference between pear and papaya in taste (p<0.05). 4. There was highly significant correlation between mechanical tenderness and sensory properties: correlation of fruit and mechanical tenderness was -.877(p<0.01); between mechanical tenderness and overall acceptability, r = .532(p<0.01); between fruit and sensory tenderness, r = .495(p<0.01); between mechanical tenderness and sensory tenderness, r = .490(p<0.01). At p<0.05, between taste and juiciness, r = .208.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.462-466
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• 2010

The purpose of this study is to evaluate the safety of a wire connector fabricated for the effective installation of a lighting fixture including its contact resistance, insulation resistance, withstanding voltage characteristics, etc., and to provide the basis for the analysis and judgment of PL(Product Liability) dispute by presenting a damage pattern due to a general flame and overcurrent. This study applied the Korean Standard (KS) for the incombustibility test of the connector using a general flame and performed an overcurrent characteristics test of the connector using PCITS (Primary Current Injection Test System). The contact resistance of the housing connector was measured using a high resistance meter and the insulation resistance was measured using a multimeter. In addition, a supply voltage of AC 1,500V for testing the withstanding voltage characteristics was applied to both ends of the connector. Measurement was performed on 5 specimens and the measured values were used as a basis for judgment. Since the connector is fabricated in the form of a housing, it can be connected and separated easily and has a structure that allows no foreign material to enter. In addition, since it has a structure that allows wires to be connected only when their polarity is identical, any misconnection that may occur during installation can be prevented. When the incombustibility test was performed by applying a general flame to the connector, it showed outstanding incombustibility characteristics and the blade and blade holder connected to the housing remained firmly secured even after the insulation sheath (PVC) was completely destroyed by fire. In addition, the mechanism of the damaged connecting wire showed a comparatively uniform carbonization pattern and it was found that some residual melted insulation material was attached to both ends. In the accelerated life test (ALT) to which approximately 500% of the rated current was applied, the connector damage proceeded in the order of white smoke generation, wire separation, spark occurrence and carbonization. That is, it could be seen that the connector damaged by overcurrent lost its own metallic color with traces of discoloration and carbonization. The contact resistance of the connector at a normal state was 2.164mV/A on average. The contact resistance measured after the high temperature test was 3.258mV/A. In addition, the insulation resistance after the temperature test was completed was greater than $10G\Omega$ and the withstanding voltage test result showed that no insulation breakdown occurred to all specimens showing stable withstanding voltage and insulation resistance characteristics.