• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.185-192
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• 1993

A numerical model has been used for the prediction of wave agitations in a harbor which are induced by the intrusion and transformation of incident waves. Based on linear wave theory a mild-slope equation has been used. A partial absorbing boundary condition has been used on solid boundary. Functional has been derived following Chen and Mei(l974)'s technique based on Hybrid Element Method which uses finite discretisation in the inner region and analytical solution of Helmholtz equation in the outer region. Final simultaneous equation has been solved using the Gaussian Elimination Method. Helmholtz natural period and second peak period of seiche in Donghae Harbor coincide very well with the results from numerical calculation. Computed amplification factors show good agreement, especially when the reflection coefficient on solid boundary is 0.99, with those of measurements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.193-206
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• 1993

An analytical model of undertow is presented in the surf zone. Each term of the derived governing equation is evaluated by the ordering methods. Then the turbulent normal stresses and the streaming velocity terms are neglected. The driving force of undertow is derived from the wave profile which is approximated by the 4th order Chebyshev polynomials. The three types of vertical distribution of eddy viscosity are assumed and the coefficient of eddy viscosity is decided from the new boundary condition. So the input parameters for the calculation of undertow become very simple. The theoretical solutions of the present model are compared with the various experimental results. This model shows a good agreement with the experimental results in the case of mild slope and linear type eddy viscosity.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1110-1116
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• 2003

The effects of packaging methods on the storage quality of minimally processed (prepeeled) onions were investigated to determine the optimal packing design. Various packaging treatments used for modifying headspace atmospheres included two passive MAP using LDPE and PP films, two active MAP using a gas mixture of 20% $O_2/10%\;CO_2/balance\;N_2$ and an ethylene scavenging sachet, and moderate vacuum packaging (MVP). The quality attributes of onion samples were evaluated periodically in terms of flesh weight loss, color of cut surface, decay ratio, microbial counts, and sensory properties during storage at $10^{\circ}C$ for 28 days. Packaging methods did not significantly influence surface color, weight loss, and microbiological populations of mesophiles, psychrotrophs, and lactic acid bacteria. They did, however, affect sensory characteristics as well as decay occurrence. Results indicated that seal-packaging with a gas-permeable plastic film under a mild vacuum condition could retain better onion quality in terms of microbial decay and visual sensory aspects as compared with the other packages.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.8-13
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• 1989

The rate constant and reaction order of the autoxidation of methyl linolenate were determined by using nuclear magnetic resonance spectrometer, and the applicability of nmr to the kinetic study was examined. The autoxidation was carried out under a mild condition, i.e., the air flow rate of 90m1/min and room temperature. The autoxidation of methyl linolenate followed the first-order kinetics, and the rate constant was found to be $1.96{\times}10^{-2}hr^{-1}$.

• Journal of Chest Surgery
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• v.30 no.11
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• pp.1105-1110
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• 1997

Essential hyperhidrosis is a condition with excessive sweating, which may be localized in any part of the body Excessive sweating has a strong negative impact on the qual ty of life for many persons. From June 1992 to May 1996, 211 cases of thoracoscopic thoracic sympathectomy were performed in the Department of Thoracic Surgery, Yongdong Severance Hospital, Seoul, Korea. Among the 211 cases, 192 patients had palmar hyperhidrosis, and 19 cases had facial hyperhidrosis. There were 121 males and 90 (tamales, and the ages ranged from 10 to 67 years(average: 24.82 years old). The average operation time and the average postoperative hospital stay were 91.94 minutes and 4.31 days, respectively. Perioperative courses were uneventful, and all the patients had immediate and complete relief of symptoms with mild compensatory sweating on the chest wall and the back. Even though a thoracoscopy has the possibility of emergency conversion to a thoracotomy and technical difficulties still exist, especially in patients with facial hyperhidrosis, our experience indicates that video-assisted thoracoscopic thoracic sympathectomy is a very safe and useful procedure for h perhidrosis.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.13 no.1
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• pp.48-53
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• 2013

Tyrosinemia I (fumarylacetoacetate hydrolase deficiency) is an autosomal recessive inborn error of tyrosine metabolism that produces liver failure in infancy or a more chronic course of liver disease with cirrhosis, often complicated by hepatocellular carcinoma in childhood or early adolescence. We studied a 37-year-old woman with tyrosinemia I whose severe liver disease in infancy and rickets during childhood were resolved with dietary therapy. From 14 years of age, she resumed unrestricted diet with the continued presence of the biochemical features of tyrosinemia, yet maintained normal liver function. In adult years, she accumulated only a small amount of succinylacetone. Despite this evolution to a mild biochemical and clinical phenotype, she eventually developed hepatocellular carcinoma. Her fumarylacetoacetate hydrolase genotype consists of a splice mutation, IVS6-1G>T, and a novel missense mutation, p.Q279R. Studies of resected liver revealed the absence of hydrolytic activity and immunological expression of fumarylacetoacetate hydrolase in tumour. In the non-tumoral areas, however, 53% of normal hydrolytic activity and immunologically present fumarylacetoacetate hydrolase were found. This case demonstrates the high risk of liver cancer in tyrosinemia I even in a seemingly favorable biological environment. In this study of tyrosinemia I, Case 2 with negative succinylacetone accumulation and the recovery of acute liver failure was compared with Case 1. Diet restriction and NTBC treatment are crucial to prevent hepatocellular carcinoma until liver transplant can take place and cure the condition. Further studies are needed to examine cases where liver cancer did not result despite clinical symptoms/signs of tyrosinemia type I.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.401-407
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• 2018

Background: In Korea, seeds of Panax ginseng C. A. Meyer need to be stored under cold temperature and high humidity condition for months to break physiological dormancy, making storage difficult until spring-sowing. This study was conducted to test the effects of seed storage conditions and seed treatment on the emergence of seedling after spring-sowing in a nursery greenhouse. Methods and Results: After dehiscence, endocarp dried seeds in mild or completely, and wet seeds were stored in $2^{\circ}C$ and $-3.5^{\circ}C$ during winter. Storage at $-3.5^{\circ}C$ resulted in a lower emergence rate (ER) than that at $2^{\circ}C$, and additional cold ($2^{\circ}C$) treatment before or after storage at $-3.5^{\circ}C$ increased the ER. Endocarp dehydration prevented pre-germination at $2^{\circ}C$ storage and increased the ER of seeds stored at $-3.5^{\circ}C$. ER was also dependent on the batch of seeds. However, seed treatments before sowing had only limited effects on ER. Root loss was the main reason for damping-off; prolonged cold storage of seeds increased damping-off, as the detection of pathogens was not high. Conclusions: This study showed that storage conditions such as temperature and moisture content of seeds, affect the ER after spring-sowing and vitality of seedlings, suggesting further attention on seed control for secure seedling stands after spring-sowing.

• KSBB Journal
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• v.22 no.4
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• pp.244-248
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• 2007

The treatment of a model wastewater containing high concentration, 10 $g/{\ell}$, of phenol in an integrated wet oxidation-aerobic biological treatment was investigated. Partial wet oxidation under mild operating conditions was capable of converting the original phenol to biodegradable organic acids such as maleic acid, formic acid and acetic acid, the solution of which was subjected to the subsequent aerobic biological treatment. The wet oxidation was carried out at 150$^{\circ}C$ and 200$^{\circ}C$ and the initial pH of 1 to 12. The high temperature of 200$^{\circ}C$ and the acidic initial condition in the wet oxidation led to effluents of which biodegradability was higher in the subsequent biological oxidation process, as assessed by chemical oxygen demand (COD) removal. Homogeneous catalyst of $CuSO_4$ was also used for increasing the oxidation rate in the wet oxidation at 150$^{\circ}C$ and initial pH of 3.0. However, the pretreatment with the catalytic wet oxidation resulted in effluents which were less biodegradable in the aerobic biological process compared to those out of the non-catalytic wet oxidation at the same operating conditions.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.700-703
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• 2010

In this study, plant extracts including Eucommia ulmoides Oliv. and Phellodendron amurense were studied to test possible application for cosmetics and skin related medicine. Anti-oxidation effect of plant extracts was measured by DPPH free radical scavenging activity and it was insignificant at low concentration, however, it was as good as vitamin C, excellent anti-oxidation agent, at $1000{\mu}g/ml$. Anti-bacterial effect was tested by disc diffusion method, and plant extracts showed mild anti-bacterial effect for normal skin flora, Staphylococcus epidermidis while it indicated strong anti-bacterial effect for acne inducing Propionibacterium acne. Therefore it had powerful potential for anti-acne material because of selectivity. Anti-atopic dermatitis effect was tested by hairless mouse and plant extracts recovered damaged skin to near normal condition after 14 days of treatment. IgE concentration in treated mouse was decreased 16% compared with control. From the research, plant extracts indicated strong anti-acne and anti-atopic dermatitis effect, and showed strong potential for cosmetics and skin related medicine.

• Corrosion Science and Technology
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• v.7 no.5
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• pp.283-287
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• 2008

The drag reduction agency (DRA) for gas pipeline, a novel method used for reducing friction or drag on a gas flowing to increase the transmission efficiency of gas pipeline, is a more flexible and economical technology than internal flow efficient coatings. In this paper, an effective DRA has been developed in Authors' Institute by analyzing the hydrodynamic friction resistance on internal gas pipeline and then studying the work mechanism and molecular structure of DRA. In the meantime, a group of property test for selecting DRA material has been determined, including viscosity, contact angle, volatility, corrosion, slab extending, and flow behavior in horizontal tube. The inhibition efficiency and drag reduction efficiency of the developed DRA have been investigated finally based on the relevant test methods. Results of corrosion test show that the developed DRA has very good inhibition effect on mild steel by brushing a thin layer of DRA on steel specimens, giving inhibition efficiency of 91.2% and 73.1% in 3%NaCl solution and standard salt fog environment respectively. Results of drag-reducing test also show that the Colebrook formula could be used to calculate friction factors on internal pipes with DRA as the Reynolds number is in the range of $0.75\times10^5\sim2.0\times10^5$. By comparing with normal industrial pipes, the friction resistance coefficient of the steel pipe with DRA on internal wall decreases by 13% and the gas flux increases by 7.3% in testing condition with Reynolds number of $2.0\times10^5$.