• Journal of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.65-72
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• 1993

A numerical method for nonlinear free-surface-wave problem is developed in this paper. The final goal of this study is to simulate the towing tank experiment of a ship model and to partially replace the experiment by the numerical model. The exact problem in the scope of potential flow theory is formulated by a variational principle based on the classical Hamilton's principle. A localized finite element method is used in the present numerical computations which made use of the following two notable steps. The first step is an efficient treatment of the numerical radiation condition by using the intermediate nonlinear-to-linear transition buffer subdomain between the fully nonlinear and linear subdomains. The second is the use of a modal analysis in the final stage of the solution procedures, which enables us to reduce the computation time drastically. With these improvements the present method can treat a much larger computational domain than that was possible previously. A pressure patch on the free surface was chosen as an example. From the present computed results we could investigate the effect of nonlinearity on the down-stream wave pattern more clearly than others, because much larger computational domain was treated. We found, specifically, the widening of the Kelvin angle and the increase of the wave numbers and the magnitude of wave profiles.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.177-183
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• 2005

The effluent quality is directly affected by the separation of biological solids in a final clarifier because the majority of discharged $BOD_5$ and SS are virtually dependent on the results of biological solids in the sedimentation tank effluent. If a final clarifier is effectively designed and operated, the desired goal of clarification for wastewater can be achieved together with the cost reduction in the treatment of wastewater. To this end flow characteristics and the removal efficiency of SS are numerically investigated especially by the change of the inlet position and the installation of baffle to improve the performance of a rectangular final clarifier. The 2-D computer program developed in a rectangular coordinates has been successfully validated against experimental residence time distribution(RTD) curves obtained by tracing radio-isotope. The lowering of the inlet position weakens the density current and induces the settling of SS in the front zone of a clarifier. Thus the decreased traveling distance of the sludge increases the removal efficiency of SS in the effluent. The inlet baffle installed in the front region of clarifier prevents the short circuiting flow and induces to flow into the dense underflow, which eventually improves the effluent quality. In the case of lower inlet position, however, installation of baffle results in degradation of effluent quality. Consequently it is strongly recommended that in-depth numerical study be performed in advance for optimizing a clarifier design and retrofitting to improve effluent quality in a final clarifier.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.359-373
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• 1993

The ultimate objective of periodontal therapy is not only stopping the progression of periodontal disease, but also promoting the regeneration of lost periodontal tissue. Guided Tissue Regeneration, which is based on the principle that the goal of periodontal regeneration can be achieved by preventing apical migration of gingival epithelium and blocking cells originating from connective tissue, has been developed and used as a clinical procedure, and although it has shown excellent results in connective tissue healing, there have not been many studies showing its effect on the regeneration of alveolar bone loss due to periodontal disease. The objectives of this study are to investigate the result of 12 months-long treatment following guided tissue regeneration using expanded polytetrafluoroehylene membrane, and to observe the presence of regenerated alveolar bone. Forty-one teeth from 28 patients with clinical diagnosis of periodontitis has been selected. In fifteen of those interproximal intrabony defects, only flap operation had been carried out, and designated as the control group. Twenty-six intrabony defects received e-PTFE membrane following flap operation, and designated as the experimental group. Eleven teeth whose membrane had been exposed were excluded from the experiment. Various measurements including probing depth, loss of attachment, probing bone level and gingival recession have been recorded at 6th month and 12th month, and the significance of the changes has been analyzed. The results are as follows: 1. Probing depth at 6th and 12th month has shown a significant decrease in both groups (p<0.01), but significantly higher decrease was found in the experimental group compared to the control at the month(p<0.05). 2. Loss of attachment at 6th and 12th month has shown a significant decrease in both groups, but significantly higher decrease was found in the experimental group compared to the control (p<0.05). 3. Probing bone level at 6th and 12th month has shown a insignificant decrease in the control group and significant decrease in the experimental group (p<0.01). Significantly higher decrease in probing bone level was found in the experimental group (p<0.05). 4. Gingival recession at 6th and 12th month has shown a statistically significant increase (p<0.05), and the control group showed higher increase compared to the experimental group although no statistical significance was found. As these results have shown, the use of e-PTFE membrane in intrabony pockets results in marked decrease in the loss of attachment and probing bone level. This seems to indicate that e-PTFE membrane may play a role in alveolar bone regeneration in intrabony defects.

• Journal of East-West Nursing Research
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• v.2 no.1
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• pp.83-95
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• 1997

Cooking food is very important in Chinese medicine when we regard the food to be the principal origin of the nutrition of human body and the condition required to maitain the activities of the life of human body. Chinese medicine has accumulated the diverse and rich experience of cooking food through long clinical experience as well as made an important contribution to the healthy and long life through the unique theory of cooking food. Chineses medicine has deep view on the relations between food cooking and healthy and long life as well as presented the principle of cooking food created unique ways of food cooking such as food treatment. As the above, from the ancient times, Chinese medicine established Chinese medical science of nutrition under the consciousness of the theory that food and medicine have the same origin and practiced the methods of promoting the health through rightly selecting the foods. Therefore it has been thought that human beings can enjoy healthy life by rich supply of the nutrition. Comfortable ways of sleeping requie the emotion and peace with temperation in pleasure and anger, and also we should be temporate in eating, acting, sleeping posture and be flee from the wind, and we should not put on a quilt when sleep, and we should sleep alone and be careful about sexual life. The concrete measures for sexual intercourse are that: 1) we should marry at the right age not to be married at early age. 2) we should obey nature and not live unmarried life. 3) we should be temperate in having sexual intercoure and in excessive sexual desire. Regarding the residence and clothes: the residence environment should be calm and beautiful and the room for the residence should be well designed to be clean and sanitary and we should wear suitable clothes. All living creatures are living according to the rhythm of the living body and the change of the great nature. The Reason why the living things show the periodical rhythm is not that it is the truth of the great nature, but that the living life itself shall be ceased to be existed in case of running counter to such rhythm. There are 2 specially important things: one is about food in biological view and the other is the residence in social side. By starting from the theory that food and medicine have the same origin and root, we should rightly select the foods to promote the health at the maximum, and it is very important for human to be well obeying the environment and temperate in the life of residence and mind (Choi, Sam Byun, Shon, Sook Young, 1997). As the above, the cook in Chinese medicine suggests us the suitable ways of achieving the goal of nursing. Therefore the continuous study of this field is necessary based on this my study though it is unsatisfactory at this time but it would be the basic materals in establishing the nursing science of Chinese medicine.

• International Journal of Oral Biology
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• v.40 no.2
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• pp.63-69
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• 2015

Curcumin (diferuloylmethane), a constituent of turmeric powder derived from the rhizome of Curcuma longa, has been shown to inhibit the growth of various types of cancer cells by regulating cell proliferation and apoptosis. However, a need exists to design more effective analogs because of curcumin's poor intestinal absorption. EF-24 (diphenyl difluoroketone), the monoketone analog of curcumin, has shown good efficacy in anticancer screens. However, the effects of curcumin and EF-24 on salivary gland epidermoid carcinoma cells are not clearly established. The main goal of this study was to investigate the effects of curcumin and EF-24 on cell growth and induction of apoptosis in human salivary gland epidermoid carcinoma cells. Our studies showed that curcumin and EF-24 inhibited the growth of HTB-41 cells in a dose- and time-dependent manner, and the potency of EF-24 was > 34-fold that of curcumin. Treatment with curcumin or EF-24 resulted in nuclear condensation and fragmentation in HTB-41 cells, whereas the control HTB-41 cell nuclei retained their normal regular and oval shape. Curcumin and EF-24 promoted proteolytic cleavages of procaspase-3/-7/-9, resulting in an increase in the amount of cleaved caspase-3/-7/-9 in the HTB-41 cells. Caspase-3 and -7 activities were detected in viable HTB-41 cells treated with curcumin or EF-24. These results suggest that the curcumin and EF-24 inhibit cell proliferation and induce apoptosis in HTB-41 human salivary gland epidermoid carcinoma cells, and that they may have potential properties as an anti-cancer drug therapy.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.511-524
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• 2005

The regeneration of lost periodontal tissue is a major goal of therapy. Periodontal ligament cell(PDL) is a specialized connective tissue that connects cementum and alveolar bone to maintain and support teeth in situ and preserve tissue homoeostasis. Bone morphogenetic proteins(BMPs) have shown much potential in the reconstruction of the periodontum by stimulate new bone and new cementum formation. Limitiations of BMP administration to periodontal lesions is high dose delivery, BMP transient biological activity, and low bioavailability of factors at the wound site. Gene delivery method can be alternative treatment strategy to deliver BMPs to periodontal tissue. The purpose of this study is to investigate efficiency of BMP-2 gene delivery with cell-based therapy using PDL cells. PDL cell were transduced with adenoviruses encoding either BMP-2 or Lac-Z gene. To evaluate osteogenic activity of expressed BMP-2 on PDL cells, we investigated secreted BMP-2, cellular activity, ALPase, produced mineralized nodules. To evaluate collagen scaffold as carrier for transduced cell delivery, we examined morphology and secreted BMP-2 of transducd PDL cells on it. BMP-2 transducd PDL cells produced higher levels of BMP-2, ALPase, mineralized nodules than non transduced cells. Cellular activity of transduced cells was showed similar activity to non transduced cells. Transduce cells attached on collagen scaffold secreted BMP-2 at 7day and was showed similar morphology to non transduced cells. These results demonstrated that transduced PDL cells produced biologically active BMP-2 and collagen scaffold could be carrier of transducd cells.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.461-474
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• 2005

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue and the repair of function. For more than a decade there have been many efforts to develop materials and methods of treatment to promote periodontal tissue regeneration. Recently many efforts are concentrated on the regeneration potential of material used in traditional medicine. Safflower(Carthamus tinctorius L.) seed extract(SSE) have long clinically used in Korea to promote bone formation and prevent osteoporosis. The purpose of this study was to examine the effects of SSE on bone formation in human osteoblastic cell line. Human fetal osteoblastic cell line(hFOB 1.19) was cultured with DMEM and SSE($1{\mu}g/ml$, $10{\mu}g/ml$, $100{\mu}g/ml$, $1mg/ml$) at $34^{\cdot}C$ with 5% $CO_2$ in 100% humidity. The proliferation, differentiation of the cell was evaluated by several experiments. Cell proliferation was significantly increased at $10{\mu}g/ml$, $100{\mu}g/ml$, 1mg/ml of SSE after 3 and 7 days incubation(p<0.05). Cell spreading assay was significantly increased at $100{\mu}g/ml$ of SSE after 3 days and $1{\mu}g/ml$, $10{\mu}g/ml$, $100{\mu}g/ml$, 1mg/ml of SSE after 7 days(p<0.05). Alkaline Phosphatase(ALP) level was significantly increased in $10{\mu}g/ml$, $100{\mu}g/ml$, 1mg/ml of SSE(p<0.05). Collagen synthesis was significantly increased at $10{\mu}g/ml$, $100{\mu}g/ml$, 1mg/ml of SSE(p<0.05). A quantified calcium accumulation was significantly increased at $10{\mu}g/ml$, $100{\mu}g/ml$ of SSE(p<0.05). ALP and osteocalcin mRNA was expressed in $100{\mu}g/ml$ of SSE by RT-PCR. These results indicate that SSE are capable of increasing osteoblasts mineralization and may play an important role in bone formation.

• Journal of Adhesion and Interface
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• v.3 no.4
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• pp.1-9
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• 2002

The main goal of this study was to analyze the effect of process additives, i.e. maleated polypropylene (MAPP), and nucleating agent on the viscoelastic properties of different types of extruded polypropylene-wood plastic composites manufactured from either PP homopolymer, high crystallinity PP or PP impact copolymer using dynamic mechanical thermal analysis. And also, the esterification reaction between wood flour and maleated polypropylene, and its role in determining the mechanical properties of wood flour-polypropylene composites was investigated. The wood plastic composites were manufactured using 60% pine wood flour and 40% polypropylene on a Davis-Standard $Woodtruder^{TM}$. Dynamic mechanical thermal properties, polymer damping peaks(than ${\delta}$), storage modulus (E') and loss modulus (E") were measured using a dynamic mechanical thermal analyzer. XPS (X-ray Photoelectron Spectroscopy), also known as ESCA (Electron Spectroscopy for Chemical Analysis) study of wood flour treated with MAPP was performed to obtain information on the chemical nature of wood fiber before and after treatment. To analyze the effect of frequency on the dynamic mechanical properties of the various composites, DMA tests were performed over a temperature range of -20 to $100^{\circ}C$, at four different frequencies (1, 5, 10 and 25 Hz), and at a heating rate of $5^{\circ}C/min$. From these results, the activation energy of the various composite was measured using an Arrhenius relationship to investigate the effect of maleated PP and nucleating agent on the measurement of the interphase between the wood and plastic of the extruded polypropylene wood plastic composites.

• Korean Journal of Clinical Pharmacy
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• v.12 no.1
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• pp.29-38
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• 2002

Hypertension is an important public health problem because it increases the risk of stroke, angina, myocardial infarction, heart failure, and end-stage renal disease. If it is not actively treated, morbidity and mortality increase with hypertension-induced complications and quality of life decreases. This study was to evaluate the use of antihypertensive drugs and blood pressure changes and to compare algorithms chosen (or the 1st and 2nd line therapy of hypertension based on the JNC VI recommendations. The medical charts of 222 patients with essential hypertension at St. Vincent's Hospital in Suwon from January 1997 to January 2000 were reviewed retrospectively. Data collection and analysis included baseline BP underlying diseases and complications, administered antihypertensives, BP changes, changes of antihypertensive regimen, and adverse effects with treatments. As results, the higher BP the patients had, the more frequent they had target organ damages and clinical cardiovascular diseases. Mean duration to reduce blood pressure less than 140/90 mmHg was 8 weeks in $85.3\%$ of the patients. The rate of control in BP was $82.4\%$ at 6 months. The major antihypertensive drugs prescribed were calcium channel blockers $(61.8\%)$ , ACE inhibitors $(19.1\%),\;\beta-blockers\;(13.7\%)$ and diuretics $(5.3\%)$ as the 1st-line monotherapy. The methods of treatment used as the 1st-line therapy were monotherapy$(59\%)$ and combination therapy $(41\%)$. Blood pressure change was significantly greater for combination therapy than monotherapy$(-26.2\pm21.4\;vs.\;-18.56\pm16.7$ mmHg for systolic blood pressure; P<0.003, $-16.9\pm13.2\;vs.\;-9.2\pm12.8$ mmHg for diastolic blood pressure; p<0.001). When blood pressure was not completely controlled with the first antihypertensive selected, the 2nd line therapy had 4 options: addition of 2nd agent from different class; $66.2\%$, substitution with another drug, $21.9\%$ increase dose $11.9\%$ continue first regimen $27.9\%$ Calcium channel blockers were the most frequently prescribed agents. This was not comparable to the JNC VI guideline which recommended diuretics and $\beta-blockers$ for the 1st-line therapy. Most of patients achieved the goal BP and maintained it until 6 months, but the remaining patients should be controlled more tightly to improve their BP with combination of life style modification, patient education, and pharmacotherapy.

• Journal of the Korea Convergence Society
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• v.6 no.2
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• pp.13-18
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• 2015

The purpose of the study is to investigate the predisposing factors of posttraumatic stress disorder (PTSD) in fire fighters in Korea and to suggest the program development and solution to the critical incident stress management (CISM) in the future. PTSD is characterized by invasion, withdrawal, negative change of cognition and mood, and hypersensitivity. Trauma memory includes explicit memory and implicit memory. The explicit memory is conscious, cognitive, and descriptive and is controlled by hippocampus. The data of explicit memory have inhibitive and narrative language structure. The implicit memory is inconscious, emotional, and remembered by the body. The implicit memory is controlled by amygdala and has inexpressive language structure. The deletion of implicit memory is the key point to trauma treatment. Critical incident stress management (CISM) is the approach for the solution of PTSD. In conclusion, the essential goal of CISM is the psychological cessation of PTSD. This study tried to suggest the education program development of PTSD.