• Journal of The Geomorphological Association of Korea
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• v.23 no.3
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• pp.41-55
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• 2016

The granulometric characteristics and chemical composition of the samples from the Bukpyeong myeon, Hainam gun, Jeollanam do were analyzed in this study. The samples were collected from the outcrop of coastal area where the height is about 30m. The burial age of the sediments also estimated by OSL(Optically Stimulated Luminescence) method. The origin and forming processes of the samples are not clear in this stage as limited number of evidences can be found. However it is suggested that the samples are not aeolian deposits originated from chinese loess by the chemical analysis. The mean diameter of samples were $5{\sim}6{\varphi}(silt)$ and are increased slightly downwards. The samples also well sorted. The samples have been heavily weathered by the chemical alteration index. The value of CIA increase downward rapidly at the upper part of outcrop, then stabilized afterwards. The vertical concentration changes ratio of cations varies; Si increases downwards while Fe, Ti, K and Mg decrease. There are fluctuation in concentration ratio of Na and Ca with increasing depth. The burial age of sample from upper part are estimated as $104.52{\pm}4.45ka\;BP$, while that of lower part are $136.10{\pm}6.52ka\;BP$, and they fall in to last part of MS6. The deposition rate for this site is found about 0.017mm/year. The uplift rate of the site is supposed to be 0.24~0.26m/ka with assumption of palaeo-sea level of +6m. However the origin of the sediment deposits should be explored and cleared.

• Journal of Korean Society on Water Environment
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• v.37 no.5
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• pp.369-380
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• 2021

In this work, we analyzed the effects of drought on the water temperature (WT) of Nakdong river basin major river sections using Standardized Precipitation Index (SPI) and WT data. The analysis was carried out on a seasonal basis. After calculating the optimal time scale of the SPI through the correlation between the SPI and WT data, we used the copula theory to model the joint probability distribution between the WT and SPI on the optimal time scale. During spring and fall, the possibility of environmental drought caused by high WT increased in most of the river sections. Notably, in summer, the possibility of environmental drought caused by high WT increased in all river sections. On the other hand, in winter, the possibility of environmental drought caused by low WT increased in most river sections. From the risk map, which quantified the sensitivity of WT to the risk of environmental drought, the river sections Nakbon C, Namgang E, and Nakbon K showed increased stress in the water ecosystem due to high WT when drought occurred in summer. When drought occurred in winter, an increased water ecosystem stress caused by falling WT was observed in the river sections Gilan A, Yongjeon A, Nakbon F, Hwanggang B, Nakbon I, Nakbon J, Nakbon K, Nakbon L, and Nakbon M. The methodology developed in this study will be used in the future to quantify the effects of drought on water quality as well as WT.

• Geomechanics and Engineering
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• v.18 no.5
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• pp.535-543
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• 2019

Building on/with expansive soils with no treatment brings complications. Compacted expansive soils specifically fall short in satisfying the minimum requirements for transport embankment infrastructures, requiring the adoption of hauled virgin mineral aggregates or a sustainable alternative. Use of hauled aggregates comes at a high carbon and economical cost. On average, every 9m high embankment built with quarried/hauled soils cost $12600MJ.m^{-2}$ Embodied Energy (EE). A prospect of using mixed cutting-arising expansive soils with industrial/domestic wastes can reduce the carbon cost and ease the pressure on landfills. The widespread use of recycled materials has been extensively limited due to concerns over their long-term performance, generally low shear strength and stiffness. In this contribution, hydromechanical properties of a waste tyre sand-sized rubber (a mixture of polybutadiene, polyisoprene, elastomers, and styrene-butadiene) and expansive silt is studied, allowing the short- and long-term behaviour of optimum compacted composites to be better established. The inclusion of tyre shred substantially decreased the swelling potential/pressure and modestly lowered the compression index. Silt-Tyre powder replacement lowered the bulk density, allowing construction of lighter reinforced earth structures. The shear strength and stiffness decreased on addition of tyre powder, yet the contribution of matric suction to the shear strength remained constant for tyre shred contents up to 20%. Reinforced soils adopted a ductile post-peak plastic behaviour with enhanced failure strain, offering the opportunity to build more flexible subgrades as recommended for expansive soils. Residual water content and tyre shred content are directly correlated; tyre-reinforced silt showed a greater capacity of water storage (than natural silts) and hence a sustainable solution to waterlogging and surficial flooding particularly in urban settings. Crushed fine tyre shred mixed with expansive silts/sands at 15 to 20 wt% appear to offer the maximum reduction in swelling-shrinking properties at minimum cracking, strength loss and enhanced compressibility expenses.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.172-177
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• 2019

Seasonal fluctuation in abundance and species composition of fish in coastal waters off Dolsan island were investigated using seasonal samples collected by an otter trawl in 2012. A total of 4,848 fishes were sampled and classified into 52 species, 29 families, and 7 orders. The dominant species was Leiognathus nuchalis (2,786 individuals, 57.5%), Amblychaeturichthys hexanema (164 individuals, 3.4%), and Ilisha elongata (141 individuals, 2.9%). The highest number of individuals was found in summer (2,174 individuals), while the lowest number of individuals was found in winter (321 individuals). The diversity index was the highest in spring (H'=3.06) and the lowest in summer and fall (H'=1.77). Temperature was the principal factor to determine the collected number of individuals (r=0.94) and the number of species (r=0.83).

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.267-275
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• 2021

Smart application is developed in this paper by using an android-based platform to automatically determine the human emergency state (Lifesaver) by using different technology sensors of the mobile. In practice, this Lifesaver has many applications, and it can be easily combined with other applications as well to determine the emergency of humans. For example, if an old human falls due to some medical reasons, then this application is automatically determining the human state and then calls a person from this emergency contact list. Moreover, if the car accidentally crashes due to an accident, then the Lifesaver application is also helping to call a person who is on the emergency contact list to save human life. Therefore, the main objective of this project is to develop an application that can save human life. As a result, the proposed Lifesaver application is utilized to assist the person to get immediate attention in case of absence of help in four different situations. To develop the Lifesaver system, the GPS is also integrated to get the exact location of a human in case of emergency. Moreover, the emergency list of friends and authorities is also maintained to develop this application. To test and evaluate the Lifesaver system, the 50 different human data are collected with different age groups in the range of (40-70) and the performance of the Lifesaver application is also evaluated and compared with other state-of-the-art applications. On average, the Lifesaver system is achieved 95.5% detection accuracy and the value of 91.5 based on emergency index metric, which is outperformed compared to other applications in this domain.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.294-304
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• 2023

Seasonal variations in the community structure of larval fish assemblage in the coastal waters off Gadeok-do were investigated in May, August and November of 2019, and February in 2020. During the study period, a total of 85 larvae species belonging to 45 families were collected. The dominant species were Engraulis japonica, Gobiidae sp., Clupea pallasii, Decapterus maruadsi, and Callionymidae sp.. These five species accounted for 84.1% of the total number of larvae during the survey period. E. japonica, Gobiidae sp., D. maruadsi, and Callionymidae sp. were the dominant species in the summer, while C. pallasii was the dominant species in the winter. The Species Diversity Index was highest in the summer and lower in the fall and winter months, with the lowest values in the spring. As a result of cluster analysis using the number of individual larval fish showed that they are divided into four seasonal groups. In particular, due to seasonal changes in water temperature, an appropriate growth environment was formed in the summer, and an appropriate hatching water temperature for winter spawning fish species was formed in winter, reflecting the seasonal characteristics of the larval fish community.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.388-397
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• 2008

The present study was performed to evaluate the function of the mandible according to the pattern of fracture and treatment methods of condylar fractures of the mandible and help operators in making a treatment plan. Sixty patients (average follow-up period was $7.8{\pm}9.4$ months) who were treated for condylar fracture from June, 2002 to May, 2006 at the Department of Oral and Maxillofacial surgery, Chonnam National University Hospital were reviewed. The common causes of the condylar fracture were traffic accident and fall-down (35.0%). In concomitant injuries, laceration was 46.7% and the fracture of the mandibular symphysis was highest incidence (60.0%). The common site of the fracture was the condylar head (47.8%), followed by subcondyle (36.2%) and condylar neck (15.9%). Under 15 years old patients, the closed reduction was performed in 87.5% out of the patients. All of the condylar fragments were fixed to the mandible with titanium miniplates in cases of open reduction. The mean period of intermaxillary fixation (IMF) was $14.2{\pm}6.5$ days in closed reduction and $10.0{\pm}4.2$ days in open reduction. The old patient with bilateral condylar head fractures, who were treated by closed reduction with IMF for 3 weeks, showed the limitation of mandibular movements. But, there was no significant different results between open reduction and closed reduction with the respect of the Helkimo's mandibular mobility index and clinical dysfunction index (DI). Complications, such as fibrous ankylosis and resorption of the mandibular condyle, were not observed in all patients. These results suggest that the good results can be obtained by closed reduction with proper IMF periods and functional exercise in most condylar fractures of the mandible except severely displaced extracapsular fractures.

• Korean Journal of Community Nutrition
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• v.4 no.2
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• pp.132-138
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• 1999

The purpose of this study was to determine biochemical parameters related to protein and immunity. Subjects were 125 preschool children(M:69, F:56) residing in low income area of Seoul. Mean serum total protein of the children aged 6 was 7.3g/dl which was significantly higher than 6.6g/dl of the group aged 3. The mean serum albumin was 4.7g/dl for 3, 4, 5 age group, and 4.9g/dl for 6 age group and there was no significant difference. Serum retinol binding protein(RBP) is used as a sensitive indicatior of protein, because it tends to fall rapidly in response to protein status and respond to quickly dietary treatment. Mean RBP for each group(3, 4, 5 and 6 age group) were $2.5\mu{g}$/dl, $2.9\mu{g}$/dl, $2.7\mu{g}$/dl, $3.0\mu{g}$/dl. The Proportion of children whose RBP was than $2.6\mu{g}$/dl was 15.9%, 19.2%, 24.3% and 16.7%, respectively. The 24-hour urinary excretion of hydroxyproline was 7.9mg, 14.6mg, 11.7mg and 11.8mg for each group and the mean excretion of all children was 12.2mg/day. Children aged 3 were excreting significantly lower amount of hydroxprolinc per day than the children aged 4. The mean hydroxyproline index were 2.18, 2.39, 2.52, 2.80 for each age group and the mean of a group aged 6 was significantly higher than that of the group aged 3. The proportion of children assessed as malnourished and impaired growth(hydroxyproline index <2.0) was 18.8%, 4.9%, 2.5% and 4.3%, respectively. The nutrients which showed significant relationship with protein and immunity parameters were niacin, vitamin C and calcium. Vitamin C showed significant positive relationship(p<0.05-p<0.01) with serum RBP, total protein and globulin. The triceps skinfold thickness was significantly and positively correlated with serum globulin. Serum IgG showed significant positive relationship with height, weight, girth of chest and midarm circumference(p<0.05-p<0.01).

• Journal of Environmental Policy
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• v.5 no.4
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• pp.1-18
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• 2006

Recently, the damage by fresh flood increases in Gangwon-do and Gyeongsangbuk-do of the north-eastern area of Korea. Even though the recent pattern of rain fall keeps changing, there is no strategy to mitigate damage by disaster. For the appropriate measure and policy for decreasing damage, an index for vulnerability is necessary to provide evidence of local climate change. The present work analyzes the flooding damage cost during the past 20 years. During 80's, the southern area of Korea was seriously damaged by over-floods on the agricultural ground. After that time, the loss and damage has decreased in the southern area but the middle part has shown slight but distinct increases of damage. The absolute coast of damage in the northern part has kept constant. However, the relative regional damage to the total country damage has kept increasing over 20 years in the same area. The surface area of floods is strongly correlated with the regional damage cost in the southern part but the north-eastern part has weak correlation between flooded area and cost. It implies that the recent damage in the north-eastern mountain area was not caused by flood itself but the other factors such as avalanches. The present work expects that the damage cost can be a good proxy value for index for climate change impact assessment.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.6 s.119
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• pp.10-21
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• 2007

The purpose of this paper was to classify areas demanding to be transformed to green spaces and evaluate their grades for urban park and green networks. The results of this study are summarized below; 1. The results of the classified green spaces in the research areas fall into three types including children parks, neighborhood parks, and public green spaces. The three types of green spaces were analysed with recreational indexes. The zones disturbing the green-networks were sorted out. These zones should be changed into a supplementary green spaces for improving the recreational functions in the city. 2. For urban park and green networks, distances between the parks and size of the parks were adopted as indices. Based on the index of distances between the parks, disturbing zones were evaluated with 3 grades. The first grade includes primary industrial complexes and housing complexes. The second grade was observed mostly in industrial complex areas. The third grade includes housing complexes. Based on the indexes of size of parks, disturbing zones were evaluated with 2 grades. In the case of grade I, it appeared in housing complex. In the case of grade II, it appeared in industrial complex. 3. Then, we prioritized the disturbing zones with severity in order to make supplementary green spaces. Through the process, the zones of the grade I for two each recreational index were evaluated to two grades. The analysis results of evaluated zones were that grade II appeared over industrial and housing complexes widely. Grade I appeared over housing complexes. 4. It is necessary that the grade of disturbing zones should be considered as an order to make green spaces to supplement a green-network. For this, we formed a basic frame of a green-networks in Dalsu-Gu and placed the disturbing zones on the basic frame of a green-network. Consequently, The results were that the green-networks in Dalsu-Gu was composed on four green-network axes and its shape mirrored a cruciform (+) of northwest$\leftrightarrow$southeast direction and southwest$\leftrightarrow$northeast direction.