• Elastomers and Composites
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• v.51 no.2
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• pp.128-137
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• 2016

The effect of the surface area of silicas on their reinforcing performance to styrene-butadiene rubber (SBR) compounds was systematically investigated. The feasibility of the Brunauer-Emmett-Teller surface area ($S_{BET}$) as a parameter representing the characteristics of the silicas was discussed compared to the mesopore volume, c value, oil absorption, and uptake of silane. The increase in $S_{BET}$ of silicas caused a considerable increase in Mooney viscosity, minimum torque, and hysteresis loss of the silica-filled SBR compounds, while significantly enhancing their abrasion property. These changes were explained by the attrition between the hydrophilic silica surface and the hydrophobic rubber chains. As expected, the change in $S_{BET}$ did not induce any remarkable changes in the cure, processing, tensile, and dynamic properties of the silica-filled SBR compounds because the crosslinking density of the rubber chains mainly determined these properties.

• Journal of Ecology and Environment
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• v.36 no.1
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• pp.31-38
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• 2013

Annual ring formation is considered a source of information to investigate the effects of environmental changes caused by temperature, air pollution, and acid rain on tree growth. A comparative investigation of annual ring growth of Cryptomeria japonica in relation to environmental changes was conducted at two sites in southern Korea (Haenam and Jangseong). Three wood disks from each site were collected from stems at breast height and annual ring growth was analyzed. Annual ring area at two sites increased over time (p > 0.05). Tree ring growth rate in Jangseong was higher than that in Haenam. Annual ring area increment in Jangseong was more strongly correlated with environmental variables than that in Haenam; annual ring growth increased with increasing temperature (p < 0.01) and a positive effect of $NO_2$ concentration on annual ring area (p < 0.05) could be attributed to nitrogen deposition in Jangseong. The correlation of annual ring growth increased with decreasing $SO_2$ and $CO_2$ concentrations (p < 0.01) in Jangseong. Variation in annual growth rings in Jangseong could be associated with temperature changes and N deposition. In Haenam, annual ring growth was correlated with $SO_2$ concentration (p < 0.01), and there was a negative relationship between precipitation pH and annual ring area (p < 0.01) which may reflect changes in nutrient cycles due to the acid rain. Therefore, the combined effects of increased $CO_2$, N deposition, and temperature on tree ring growth in Jangseong may be linked to soil acidification in this forest ecosystem. The interactions between air pollution ($SO_2$) and precipitation pH in Haenam may affect tree growth and may change nutrient cycles in this site. These results suggested that annual tree ring growth in Jangseong was more correlated with environmental variables than that in Haenam. However, the further growth of C. japonica forest at two sites is at risk from the long-term effects of acid deposition from fossil fuel combustion.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.4
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• pp.456-461
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• 1995

Tuberculosis, a chronic infectious granulomatous disease, is presumed to be quite a rare entity. Because of the development of chemotherapy and the improvement of nutritional conditions, incidence of tuberculosis have reduced. For these reasons, tuberculosis may be overlooked in the differential diagnosis whenever dealing with a submandibular swelling. Diagnosis of tuberculous lymphadenitis consists of historical data, physical findings, laboratory tests and histologic examination. The treatment of choice seems to be surgical excision and long term antituberculosis chemotherapy. Surgery provides a rapid tissue diagnosis, because the histological examination of the excisional biopsy is the most reliable diagnostic test. This is the report of a case of tuberculous cervical lymphadenitis on left submandibular area with no evidence of the involvement of lung.

• Journal of Preventive Medicine and Public Health
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• v.23 no.2 s.30
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• pp.207-215
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• 1990

In order to investigate the occurrence characteristics of cancer in terms of industry in Kwangju-Chonnam area, medical utilization records of industrial medical insurance corporations during the period of 1987 to 1988 were reviewed for the identification of neoplastic disease. The cases obtained from the medical records were followed up for the verification and to get additional information. Standardized incidence data were compared by occupational characteristics. Multiple logistic regression analysis was applied to analyze the difference of incidence or distribution of cancer as a whole or of some selected cancer. Total cases of cancer identified were 242 during the study period. Annual incidence rate was calculated as 123.1 per 100,000 person. The frequent types of cancer were cancers of stomach, liver, lung, colon and rectum, bladder and lymphoma in descending order. Employees of mine and other sand handling industries showed significantly higher risks for cancer of stomach and cancer as a whole. Employees of the transportation industry showed the higher risk for cancer of liver, Workers in small-sized industry (${\leqq}100$) had a higher risk for cancer than who in large-sized industry (<100). These findings suggested the effect of occupational environmental exposure to cancer development.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.117-121
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• 1989

An observation on the outbreak patterns of zoonoses was carried out on 261,862 cattle, 1,967 swine, 91,500 fowl samples in Chronnam Province. And it was classified by ppsitive.reaction from numbers of request examined and diagnosis to Animal Health Center of Chonnam Province from 1983 to 1988. The results are summarized as follows: Incidence rate of zoonoses in Chonnam area was observed in the order of alveolar sarcoma of fowl (75.0%), bovine facioliasis (47.6%), bovine mastitis (19.0%), bovine salmonellosis (12.6%), salmonellosis of swine (11.0%), salmonellosis of fowl (8.9%), bovine streptogenes (6.7%), tetanus of bovine (2.0%), streptogenes of swine (1.7%), pullorum disease (0.6%), bovine tubercullosis (0.02%), and bovine brucellosis (0.01%). And, especially bovine facioliasis was observed highest outbreaks (89.4%).

• International Journal of Contents
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• v.9 no.1
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• pp.6-10
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• 2013

Foreground estimation in object segmentation has been an important issue for last few decades. In this paper we propose a GrabCut based automatic foreground estimation method using block clustering. GrabCut is one of popular algorithms for image segmentation in 2D image. However GrabCut is semi-automatic algorithm. So it requires the user input a rough boundary for foreground and background. Typically, the user draws a rectangle around the object of interest manually. The goal of proposed method is to generate an initial rectangle automatically. In order to create initial rectangle, we use Gabor filter and Saliency map and then we use 4 features (amount of area, variance, amount of class with boundary area, amount of class with saliency map) to categorize foreground and background. From the experimental results, our proposed algorithm can achieve satisfactory accuracy in object segmentation without any prior information by the user.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.157-159
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• 1999

This paper presented design of an $H_{\infty}$ controller for TCSC to enhance the damping of an inter-area oscillation in KEPCO power system. TCSC location is selected by using eigne sensitivity and frequency response. Nonliner time simulation and eigenvalue analysis show that the proposed TCSC $H_{\infty}$ controller can suppress the inter-area oscillations efficiently with induced reduction model correctly.

• Korean Journal of Ichthyology
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• v.6 no.1
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• pp.28-38
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• 1994

The ichthyofauna was investigated in Tongbok Lake and its tributaries from October, 1992 to January, 1993. Twenty-nine species representing 23 genera and 10 families were collected. Twenty-eight species in 22 genera and 9 families were from the stream area, while sixtween species in 14 genera and 7 families were from the lake area. Among these 14 species were classified as endemic species in Korea. Dominent species in the stream area were Zacco temmincki(28.04%) and Z. platypus (16.76%), whereas the lake area was overwhelmingly dominated by Hypomesus olidus(55.22%) and Z. platypus(44.31%). In the stream area. species diversity indices, evenness indices and dominant indices were 1.056, 0.730 and 0.270, respectively. In the area, the indices for species diversity, evenness and dominance were 0.314, 0.261 and 0.739, and those of body weights were 0.361, 0.300 and 0.700, respectively.

• The korean journal of orthodontics
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• v.26 no.1 s.54
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• pp.43-52
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• 1996

The purpose of this study was to compare and evaluate the upper airway structure between the snorers and asymptomatic control subjects depending on the positional change. Lateral cephalograms in the upright and supine position were taken in 25 female snorers and 20 female asymptomatic control subjects. The length and the area of the soft palate, tongue and airway were measured and evaluated statistically. The results obtained were as follows : 1. The snorers showed longer and higher tongue, narrower and longer airway, inferiorly positioned hyoid bone, longer and broader soft palate and narrower hypopharynx than the control subjects both in the upright and supine position. In addition, the snorers showed broader tongue area and narrower oropharynx area than the control subjects in supine position. 2. Depending on the positional change from upright to supine position, the controls and the snorers showed decreased airway length and superior positioned the hyoid bone. In addition, the snorers showed decreased tongue length and height, airway length and thickness and oropharynx area, but increased tongue area and soft palate area.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.5
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• pp.493-503
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• 2005

This survey was performed to investigate the distribution of specialities which cultivated importantly in Jeollabukdo area in order to understand food culture of this area. Foods in speciality were divided into 4 groups, agricultural, aquatic, animal and the others products. Total number of 93 species of specialities, including 40 species of agricultural products, 29 species of aquatic products, 8 species of animal products and 16 species of the miscellaneous products, were identified from Jeollabukdo area. Especially, there were various fruits and vegetables among agricultural products and fishes among aquatic products in this region. Rice, pepper, pear, Mandarin fish, beef, pine mushroom, lentinus edodes and honey were determined as specialities in Jeollabukdo area. Various aquatic products were specialities in Gochang, Gunsan, Buan and Gimje region. Fruits, mushrooms, wild edible greens and animal products were specialities in Muju, Jangsu, Jeongeup and Jinan. Sweet fish, cat fish and freshwater crab were caught off in Sumjin river region only such as Namwon, Sunchang and Imsil, Recently, pumpkin(Cucurbita maxima) and paprika were determined as specialities in Jeollabukdo. In case of aquatic products, mushrooms and wild edible greens, their wild type products decreased, while cultivated type increased Commercialization by brand naming of agricultural and animal products were rapidly increasing. The kinds of specialities in Jeollabukdo area were changing by the influence of geographical, religious and social factors.