• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.506-510
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• 2017

Based on the Jansen mechanism theory, a walking robot is developed, which is able to trace a line. In order to find the optimized legs, GL(Ground Length), GAC(Ground Angle Coefficient) and Grashof criteria are utilized in m.sketch program as well as EdisonDesign program. Many types of design are applied to sensors and controls, and the functionality is checked. Finally, a prototype line tracer robot is manufactured using aduino parts and smart boards. The prototype robot is test run to check the validity of the design, and modifications are applied to improve the performance according to each test result until the best design is achieved.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.439-444
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• 2005

A 7.1 kg, seven-year old, castrated male, Shih-Tzu with severe pruritus, chronic otitis externa and Malassezia infection was referred to Veterinary Medical Teaching Hospital of Chungnam National University. In local animal hospital, steroid therapy was used to treat uncontrollable pruritus, but the clinical signs were recurrent when steroid therapy was discontinued. On physical examination, generalized alopecia, erythema, papules, severe crust and diffuse lichenification were presented. Tape strip test of skin lesions revealed cocci and Malassezia infections. Based on the result of history, clinical signs and examination described above, canine atopic dermatitis with secondary superficial pyoderma and Malassezia dermatitis was diagnosed. Oral challenge with cyclosporine and antibiotics had good results in clinical signs. Clinical sign scores were evaluated by investigator with CADESI at 2weeks, 4weeks, 6weeks, 8weeks and 10weeks after cyclosporine administration. And in the result of comparing of allergen-specific IgE value, the level of allergen-specific IgE to general causative allergen after 10 weeks of cyclosporine therapy was higher than that before cyclosporine therapy.

• Proceeding of EDISON Challenge
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• 2016.11a
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• pp.63-67
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• 2016

본 연구에서는 극초음속 추진기관을 위한 고공환경 모사 설비 장치에서 시험부 안에 들어가는 시험 모델의 변수에 대해 고찰하였다. 시험부에 적용할 시험 모델을 대상으로 진행하고, 시험 모델 형상 변화에 따른 유동 특성을 파악하였다. 시험 모델에 대한 주요 변수는 폐색율, 각도, 받음각으로 설정하였으며, 해석은 EDISON_CFD에서 제공하는 정렬격자 기반 2차원 압축성 유동 범용 해석 SW로 진행하였다. 해석 결과를 통해 다양한 형상 변수에 따라 변화 되는 충격파 뒤의 압력층 두께를 확인 하였고, 압력층 두께가 두꺼워 질수록 시험 조건을 모사 할 수 없음을 확인하였다. 본 연구를 통해 형상 변수에 따른 극초음속 추진기관을 위한 고공모사설비에서 시험부에 적용될 시험 모델의 범위를 확인하였다.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.256-261
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• 2016

In this paper, Shape optimal design for a chair with 4 legs and 2 stretchers consisting of stainless steel was conducted. The shape was transformed by identifying stress and deformation for the part of leg and stretcher. In addition, load condition and mesh was designed using Hypermesh. The stress analysis was carried out using CSD_Elast that is one of EDISON program. In seat test, Maximum equivalent stress was showed at the contact part between seat and legs. As a result, a leg cross-section with rectangular and arch was designed. And optimal height of stretcher was found to reduce a deformation. Also, maximum deformation was reduced by designing a stretcher with ellipse cross-section. So, Optimal chair having 4 legs with rectangular cross section and 2 stretchers with ellipse cross section was shown to satisfy the safety ratio.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.1020-1033
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• 2020

This study attempted to investigate the usefulness of Rhus javanica L., Cinnamomum verum and Rosmarinus officinalis extracts which have antimicrobial and antioxidant effects without any harm on human health as natural preservatives. In terms of extraction, extraction by 70% ethanol and hot-water extraction were used for Cinnamomum verum and Rhus javanica L. respectively. For Rosmarinus officinalis, a mixed method (70% ethanol and hot-water extraction) was adopted. In terms of experimental methods, antimicrobial effects, antioxidant activity through DPPH and safety and stability of cosmetics were assessed, and a challenge test was performed, and the results found the followings: According to an antimicrobial test, good antimicrobial effects were found in bacteria (Rhus javanica L. extract) and fungi (Cinnamomum verum extract). In contrast, the Rosmarinus officinalis extract was set aside because of poor antimicrobial activity. In the mixed extract (Rhus javanica L. + Cinnamomum verum), antimicrobial effects were observed in 'complex C (mixed in a 1:1 ratio)' while both inhibitory and sterilizing effects were found in 5 different test strains at minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In addition, antioxidant effects were detected in non-mixed extract and mixed extract ('complex C'). Furthermore, a test on cosmetics which adopted '10% complex C' instead of synthetic preservative revealed safety and stability. Therefore, this study has confirmed the potential of the Rhus javanica L., Cinnamomum verum and Rosmarinus officinalis extracts as materials for natural preservatives.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.1
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• pp.57-66
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• 2002

Objective : This study was designed to investigate the interrelationship and clinical usefulness of sperm morphology by strict criteria (SM), acrosome reaction following ionophore challenge test (ARIC) and sperm penetration assay (SPA) using zona-free hamster ova as prognostic factors in in vitro fertilization. Materials and Methods: Semen samples were provided by 83 patients undergoing IVF. We first evaluated the differences between normal fertilization group and poor fertilization group on three andrologic tests. Secondly, we analyzed the relationship between the three andrologic tests and in vitro fertilization on IVF settings. Finally, we evaluated the effectiveness of the three andrologic tests as the prognostic indicators for fertilizing ability. Results: The fertilization rate of all men in the poor fertilization group was less than 30%; but there was no evidence that this poor fertilization was due to oocyte defects. The results of three andrologic tests were significatly higher in normal fertilization group. Fertilization rate (%) in vitro was highly correlated (p<0.001) with % normal sperm by SM, ARIC value (%), and SPA result. By using Receiver-Operator-Characteristic curve (ROC), we evaluated the effectiveness of these three tests. The sensitivity and specificity of SM, ARIC test and SPA in predicting fertilization potential in IVF setting were 76% and 75%, 84% and 90%, and 76% and 95%, respectively. Conclusion: Our data suggest that the three andrologic tests can be reliable tools as prognostic factors of sperm fertilizing ability. Among these test, ARIC test and SPA gave more accurate information on fertilizing capacity. ARIC test was shown to have a predictive value for fertilizing ability comparable to that of SPA that appears to be a simple and cost-effective addition to current andrology laboratory. Combined application of these three tests may give more information on predicting sperm fertilizing capacity.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.131-141
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• 1995

This study was designed to determine the relationship between sperm acrosome reaction following ionophore challenge(ARIC) and hamster ovum sperm penetration assay(SPA) as assessment of fertilizing capacity of male. ARIC test and SPA were performed in 23 fertile and 19 subfertile men. The results were as follows; Sperm concentration was significantly higher in fertile group compared with subfertile group: $114.6{\pm}64.40$ vs $61.3{\pm}46.50{\times}10^6/ml$. However, there were no significantly differences in seminal volume, motility and motility index, respectively. There was a significantly correlation between spontaneous and induced AR in fertile and subfertile group, respectively. ARIC value was significantly higher in fertile group, compared with subfertile group: $12.0{\pm}5.57%$ vs $2.6{\pm}4.96%$. Both Penetration rate(PR) and Penetration index(PI) were significantly higher in fertile group, compared with subfertile group: $97.4{\pm}7.40%$ vs $64.9{\pm}36$. 20% and $5.4{\pm}2.88$ vs $1.5{\pm}1.47$, respectively. The Positive predictive value(PPV), Negative predictive value(NPV), sensitivity and specificity of ARIC test (cut-off: 8.5) and SPA(PI cut-off : 3.0) in predicting fertility were 95.0%, 81.8%, 82.6%, 94.7% and 95.2%, 85.7%, 87.0% and 94.7%, respectively. There was no significantly difference in predicting fertility between ARIC test and SPA. In conclusion, ARIC test was shown to have a predictive value for fertilizing capacity comparable to that of the hamster ovum sperm penetration assay. Therefore, ARIC test may be a simple and cost-effective addition to existing semenology instead of SPA.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.1
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• pp.62-67
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• 2002

Purpose: The aim of this study was to investigate the age of onset and the prevalence of lactose malabsorption in early childhood in Korea. Methods: We conducted a study of lactose malabsorption by breath hydrogen test in healthy children aged between 25~96 months old. Standard lactose loading (2 g lactose/kg, maximum 40g) test was done in 129 children and cow's milk (10 mL/kg) loading in 126 children followed by breath sampling of 60 and 120 minutes after the loading. An increase above baseline of 20 ppm or more was used as a criteria for positive responses. Results: The prevalence of lactose malabsorption was 7% in 25~36 months old, 19% in 37~48 months old, 35% in 49~60 months old, 55% in 61~72 months old, 82% in 72~84 months old, 80% in 85~96 months old children. Only 1% of the children showed positive result in breath hydrogen test after the cow's milk challenge. Conclusion: The prevalence of lactose malabsorption was increased between 37 months and 60 months of age, reached to adult level of prevalence after 72 months of age. When physiological dose of lactose was used as the challenge, the number of lactose malabsorbers become clinically insignificant.

• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.425-448
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• 2004

A bioactive and degradable poly(epsilon -caprolactone)/silica nanohybrid(PSH) was synthesized for the application as a bone substitute. PSH was manufactured by using silica and polycaprolacton. PSH was manufactured in some composition after low crystaline apatite had been formed in simulated body fluid and, was used this study. The safety of the PSH was established by test of acute, and subacute toxicity, sensitization cytotoxicity and sterility. In order to assess activity of osteoblast, the test for attaching osteoblast, proliferation test for osteoblast, differentiating gene expression test are performed in vitro. And bone substitutes were grafted in rabbit's calvarium, during 8 weeks for testing efficacy of bone substitutes. Degree of osteogenesis and absorption of substitutes were evaluated in microscopic level. In result, it was not appeared that acute and subacute toxicity, sensitization in intradermal induction phase, topical induction phase and challenge phase. It was shown that the test can not inhibit cell proliferation. adversely, it had some ability to accelerate cell proliferation. The result of sterility test described bacterial growth was not detected in most test tube. The attaching and proliferation test of osteoblast had good results. In the result of differentiating gene expression test for osteoblast, cbfa1 and, alkaline phosphatase, osteocalcin and GAPDH were detected with mRNA analysis. In the PSH bone formation test, ostgeoblastic activity would be different as material constitution but it had good new bone formation ability except group #218. futhermore, some material had been absorbed within 8 weeks. Above studies, PSH had bio-compatibility with human body, new bone formation ability and accelerate osteoblastic activity. So it would be the efficient bone substitute material with bio-active and biodegradable.

• Strategy21
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• s.39
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• pp.5-46
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• 2016

North Korea's 4th nuclear test on Jan. 6 and following developments once again awakened the world into seriousness of the nuclear matters on the Korean peninsula. On March 2, UNSC adopted Resolution 2270 which is complemented by Seoul government's measures such as withdrawal from the Gaesung Industrial Complex (Feb. 9) and announcement of unilateral sanction (March 8). Seoul government also strongly urged the international community to strangle North Korea's 'financial resources.' The U.S., Japan, China, and other countries have issued unilateral sanctions to complement the UNSC measure. South Korea and the U.S. conducted their annual joint military drill (Resolve-Foal Eagle) in the largest-ever scale. North Korea, however, responded with demonstration of its nuclear capabilities and announcement of de facto 'nuclear-first' politics. North Korea test-fired a variety of delivery vehicles, threatened nuclear strikes against South Korea and the U.S., and declared itself as an 'invincible nuclear power armed with hydrogen bombs' at the 7th Workers 'Party Congress held in May, 2016. Considering the circumstantial evidences, the North's 4th nuclear test may have been a successful boosted fission bomb test. North Korea, and, if allowed to go on with its nuclear programs, will become a nuclear power armed with more than 50 nuclear weapons including hydrogen bombs. The North is already conducting nuclear blackmail strategy towards South Korea, and must be developing 'nuclear use' strategies. Accordingly, the most pressing challenge for the international community is to bring the North to 'real dialogue for denuclearization through powerful and consistent sanctions. Of course, China's cooperation is the key to success. In this situation, South Korea has urgent challenges on diplomacy and security fronts. A diplomatic challenge is how to lead China, which had shown dual attitudes between 'pressure and connivance' towards the North's nuclear matters pursuant to its military relations with the U.S, to participate in the sanctions consistently. A military one is how to offset the 'nuclear shadow effects' engendered by the North's nuclear blackmail and prevent its purposeful and non-purposeful use of nuclear weapons. Though South Korea's Ministry of Defense is currently spending a large portion of defense finance on preemption (kill-chain) and missile defense, they pose 'high cost and low efficiency' problems. For a 'low cost and high efficiency' of deterrence, South Korea needs to switch to a 'retaliation-centered' deterrence strategy. Though South Korea's response to the North's nuclear threat can theoretically be boiled down into dialogue, sanction and deterrence, now is the time to concentrate on strong sanction and determined deterrence since they are an inevitable mandatory course to destroy the North' nuclear-first delusion and bring it to a 'real denuclearization dialogue.'