• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.431-440
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• 2017

The 2016 Gyeongju Earthquake ($M_L$ 5.8) (occurred on September 12, 2016) and the 2017 Pohang Earthquake ($M_L$ 5.4) (occurred on November 15, 2017) caused unprecedented damages in South Korea. It is necessary to establish basic data related to earthquake-induced mountainous sediment-related disasters over worldwide. In this study, we analyzed previous international studies on the earthquake-induced mountainous sediment-related disasters, then classified research areas according to research themes using text-mining and co-word analysis in VOSviewer program, and finally examined spatio-temporal research trends by research area. The result showed that the related-researches have been rapidly increased since 2005, which seems to be affected by recent large-scale earthquakes occurred in China, Taiwan and Japan. In addition, the research area related to mountainous sediment-related disasters induced by earthquakes was classified into four subjects: (i) mechanisms of disaster occurrence; (ii) rainfall parameters controlling disaster occurrence; (iii) prediction of potential disaster area using aerial and satellite photographs; and (iv) disaster risk mapping through the modeling of disaster occurrence. These research areas are considered to have a strong correlation with each other. On the threshold year (i.e., 2012-2013), when cumulative number of research papers was reached 50% of total research papers published since 1987, proportions per unit year of all research areas should increase. Especially, the proportion of the research areas related to prediction of potential disaster area using aerial and satellite photographs is highly increased compared to other three research areas. These trends are responsible for the rapidly increasing research papers with study sites in China, and the research papers examined in Taiwan, Japan, and the United States have also contributed to increases in all research areas. The results are could be used as basic data to present future research direction related to mountainous sediment-related disasters induced by earthquakes in South Korea.

• Journal of Dairy Science and Biotechnology
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• v.16 no.2
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• pp.119-136
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• 1998

The lipids of milk provide energy and many essential nutrients for the newborn animal. They also have distinctive physical properties that affect the processing of dairy products. Milk fat globules mainly consist of neutral lipids like triacylglycerols, whereas the globule membranes contain the complex lipids mostly, Phospholipids are a small but important fraction of the milk lipids and are found mainly in the milk fat globule membrane and other membranous material in the skim-milk phase. The milk fats of ruminant animals are characterized by the presence of relatively high concentrations of short-chain fatty acids, especially butyric and hexanoic acids, which are rarely found in milks of non-ruminants. The fatty acids of milk lipids arise from de novo synthesis in the mammary gland and uptake from the circulating blood. The fatty acid compositions of milks are usually complex and distinctive, depending on the nature of the fatty acids synthesized de novo in the mammary gland and those received from the diet in each species. The content and composition of milks from different species vary widely; presumably, these are evolutionary adaptations to differing environments. The actual process by which these globules are formed is unkonwn, but there are indications that triglyceride-containing vesicles which bleb from endoplasmic reticulum may serve as nucleation sites for globules. Recent studies on milk have centred on the manipulation of milk lipids to increase specific fatty acids, i.e. 20-carbon omega-3 fatty acids (eicosapentaenoic acid 20:5n3, decosahexaenoic acid 22:6n3) from marine sources because the fatty acids are closely associated with a decreased risk of coronary heart disease.

• Korean Journal of Ecology and Environment
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• v.45 no.3
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• pp.263-270
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• 2012

The objectives of the study were to determine fish fauna and compositions during 2010~2011 in Walpyung Conservation Park along with analysis of fish community structures and trophic and tolerance guilds. Total number of species and individuals sampled were 31 and 2667, respectively and dominant species was Zacco platypus (46.6%) and subdominant species was Acheilognathus lanceolatus (8.7%), which were composed of >50% of the total. Total number of Korean endemic species including Microphysogobio yaluensis was 10 and the proportion of the individuals was 8.7%. Also, natural monument No. 454 of Iksookimia choii, which is endangered species and legal protected species, was sampled and the total number of individuals was only three. According to the analysis of fish community structures, species richness index in the mid-stream reach ($M_r$) was 3.145, which is higher than any other stream reaches ($U_r$ and $D_r$). In contrast, the richness index was 2.180 in the up-stream reach ($U_r$), which is minimum among the sampling sites. Species diversity index was 1.785 and 1.975, respectively in the headwater ($U_r$) and mid-stream reach ($M_r$) and the low values in the down-stream reach ($D_r$, 1.660) were due to the influences of pointsource (i.e., road construction) and non-point sources (sporadic agricultural spots). According to analysis of tolerance guilds, the proportion of tolerant species (TS), based on the number of individuals, was composed of 64.2% and sensitive species (SS) was only 3.3%, indicating a predominance of tolerant fishes in the compositions. The proportion of omnivore species (OS), however, was composed of 64.0% and insectivore species (IS) was 29.3%, indicating a predominance of omnivore fishes in the stream. The high proportions of tolerant and omnivore species in this stream indicates that the water quality and physical habitat environments were degradated in this system. For these reasons, especially natural monument and endemic fish species in this region should be protected from the massive constructions and required to provide efficient stream management strategies.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.283-296
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• 2014

The distribution of heavy metals in the stormwater runoffs from industrial sites around Shihwa Lake that implements the total pollutant load management system (TPLMS) was studied to characterize the temporal changes of metal concentrations and to assess the ecological risk in dissolved and particulate phases of the selected metals. The dissolved Co and Ni concentration demonstrated first flush and tended to decrease with increasing of the duration of rainfall. The intensity of precipitation was found to be the main controlling factor of particulate metals in the stromwater runoffs. The particulate concentration of Pb accounted for 97.2% so the particulate phase was its main form. Other metals followed the sequence: Pb>Cu>Cd>Co>Zn>Ni. The particulate-dissolved partitioning coefficient ($K_d$) indicated that the $K_d$ of Pb were bigger than that of other metals because the metal Pb in the stormwater runoffs is quickly removed into the particulate phase. In a single day rainfall event, total runoff fluxes for total metals as the sum of dissolved and particulate forms through only two sewer outlets were 2.21 kg for Co, 30.5 kg for Ni, 278.3 kg for Cu, 398.3 kg for Zn, 0.39 kg for Cd and 40.0 kg for Pb, respectively. Given the annual rainfall, the number of rain days and the basin area for total pollutant load management system (TPLMS) of Shihwa area, enormous amount of non-point metal pollutants were entered into Lake with any treatment. The dissolved metals (e.g., Ni, Cu and Zn) in the stormwater runoffs exceeded the acute water quality criteria. Additionally, all metals were significantly enriched in the particulate phase and exceeded the PEL criteria of sediment quality guidelines (SQGs). These results indicated that the heavy metals in the stormwater runoffs may pose a very high ecological risk to the coastal environments and ecosystem.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.157-165
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• 2005

Purpose : Children occupy a large proportion of burn victims. So we want to aid to pediatric burn care through the understanding of the bacterial distribution in burn wounds and antibiotic susceptibility against isolated microorganisms from burn wounds. Methods : We analysed the medical records of 213 pediatric burn patients(0~15 years), 406 samples that grew bacteria in burn wound sites. Results : Of the total 213 patients, male were 59.6% and female were 40.4%. Scalding burn was the most common(78.4%), flame burn was the second(16.4%). Pathogens were isolated in 406 samples. The most common was Pseudomonas aeruginosa(58.1%). Next were Enterococcus species, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus species, Acinetobacter species. P. aeruginosa was resistant to trimethoprim-sulfamethoxazole in 100%, cephalothin in 98.1%, ampicillin-sulbactam in 96.2%, ampicillin in 95.3%, ceftriaxone in 95.2%, tobramycin in 93.7%, cefoperazone in 68.9%, ceftazidime in 67.7%. Enterococcus species were resistant to tetracycline in 63.9%, streptomycin in 45.5%, gentamicin in 36.1%, penicillin G in 13.7%. S. aureus was resistant to gentamicin in 89.7%, tetracycline in 86.2%, ciprofloxacin in 86.2%, penicillin G in 84.3%, oxacillin in 78.4%, erythromycin in 76.5%. Acinetobacter species were resistant to ampicillin-sulbactam in 100%, gentamicin in 85.7%, ampicillin in 83.3%, piperacillin in 61.5%. Conclusion : P. aeruginosa was highly resistant to drugs like cefoperazone in 68.9%, ceftazidime 67.7%. S. aureus was highly resistant to penicillin G in 84.3%, oxacillin in 25.9 %, but none to vancomycin in 0%, teicoplanin in 2.2%. According to the study, Acinetobacter species turned out to be multi-resistant strains, so careful attention must be paid to the choice of antibiotics.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.203-218
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• 2010

The site categorization and corresponding site amplification factors in the current Korean seismic design guideline are based on provisions for the western United States (US), although the site effects resulting in the amplification of earthquake ground motions are directly dependent on the regional and local site characteristic conditions. In these seismic codes, two amplification factors called site coefficients, $F_a$ and $F_v$, for the short-period band and midperiod band, respectively, are listed according to a criterion, mean shear wave velocity ($V_S$) to a depth of 30 m, into five classes composed of A to E. To suggest a site classification system reflecting Korean site conditions, in this study, systematic site characterization was carried out at four regional areas, Gyeongju, Hongsung, Haemi and Sacheon, to obtain the $V_S$ profiles from surface to bedrock in field and the non-linear soil properties in laboratory. The soil deposits in Korea, which were shallower and stiffer than those in the western US, were examined, and thus the site period in Korea was distributed in the low and narrow band comparing with those in western US. Based on the geotechnical characteristic properties obtained in the field and laboratory, various site-specific seismic response analyses were conducted for total 75 sites by adopting both equivalent-linear and non-linear methods. The analysis results showed that the site coefficients specified in the current Korean provision underestimate the ground motion in the short-period range and overestimate in the mid-period range. These differences can be explained by the differences in the local site characteristics including the depth to bedrock between Korea and western US. Based on the analysis results in this study and the prior research results for the Korean peninsula, new site classification system was developed by introducing the site period as representative criterion and the mean $V_S$ to a depth of shallower than 30 m as additional criterion, to reliably determine the ground motions and the corresponding design spectra taking into account the regional site characteristics in Korea.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.3
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• pp.189-199
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• 2006

Purpose of study: Partial thickness skin graft is the golden standard regimen for full-thickness skin defect caused by burn or trauma. However, in case of extensive burns of more than 50% of total body surface area, the donor site is not sufficient to cover all defects. As a second choice, allograft, xenograft and synthetic materials have been used to treat skin defect. Among them the amniotic membrane(AM) was used as a biological dressing for centuries because of its potential for wound healing. In this study, quantification of EGF in AM and effect of AM-collagen complex on full thickness skin defects was examined. Materials & Methods: The concentration of EGF in fresh, deep frozen and freeze-dried AM was evaluated by ELISA. EGF-R immunostaining was performed in freeze-dried AM. SD rats weighing 250${\sim}$300g was used for wound healing experiment. Three full thickness skin defects(28mm diameter) were made on dorsal surface of SD rat. The control group was covered by Vaselin gauze and AM-collagen complex and $Terudermis^{(R)}$. was grafted in two other defects. Healing area, Cinamon's score were evaluated before biopsy. Grafted sites were retrieved at 3 days, 1 week, 2 weeks and 4 weeks after operation. H & E and Factor VIII immunohistochemical stain was performed to evaluate the microscopic adhesion and structural integrity and microvessel formation. Results: 1. EGF concentration of fresh, deep frozen and freeze-dried AM showed similar level and EGF-R was stained in epithelial layer of freeze-dried AM. 2. At 4 weeks after grafting, the healing area of AM-collagen and Terudermis group was 99.29${\pm}$0.71% and 99.19${\pm}$0.77 of original size. However, that of control group was 24.88${\pm}$2.90. 3. The Cinamon's score of AM-Collagen and $Terudermis^{(R)}$. group at 4 weeks was 15.6${\pm}$1.26 and 14.6${\pm}$3.13 and that of control group was 3.7${\pm}$0.95. Significant difference was observed among control and experimental groups(p<0.05). 4. Histologic examination revealed that AM protected leukocyte infiltration and epithelial migration was nearly completed at 4 weeks. $Terudermis^{(R)}$. group showed mild neutrophil infiltration until 2 weeks and completion of epithelization at 4 weeks. Control group showed massive leukocyte infiltration until 4 weeks. 5. Microvessels were increased sharply at 1 week and control group at 1 and 4 week showed significant differences with $Terudermis^{(R)}$. group of same interval(p<0.05) but no differences were found with AM group(p<0.05). Conclusion: EGF and EGF-R were well preserved in freeze-dried AM. AM attached to collagen acted as excellent biologic dressing which had similar effect with $Terudermis^{(R)}$. AM showed anti-inflammatory action and healing was completed at 4 weeks after full-thickness skin defect.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.107-120
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• 2014

This study proposes a novel recommender system using the structural hole analysis to reflect qualitative and emotional information in recommendation process. Although collaborative filtering (CF) is known as the most popular recommendation algorithm, it has some limitations including scalability and sparsity problems. The scalability problem arises when the volume of users and items become quite large. It means that CF cannot scale up due to large computation time for finding neighbors from the user-item matrix as the number of users and items increases in real-world e-commerce sites. Sparsity is a common problem of most recommender systems due to the fact that users generally evaluate only a small portion of the whole items. In addition, the cold-start problem is the special case of the sparsity problem when users or items newly added to the system with no ratings at all. When the user's preference evaluation data is sparse, two users or items are unlikely to have common ratings, and finally, CF will predict ratings using a very limited number of similar users. Moreover, it may produces biased recommendations because similarity weights may be estimated using only a small portion of rating data. In this study, we suggest a novel limitation of the conventional CF. The limitation is that CF does not consider qualitative and emotional information about users in the recommendation process because it only utilizes user's preference scores of the user-item matrix. To address this novel limitation, this study proposes cluster-indexing CF model with the structural hole analysis for recommendations. In general, the structural hole means a location which connects two separate actors without any redundant connections in the network. The actor who occupies the structural hole can easily access to non-redundant, various and fresh information. Therefore, the actor who occupies the structural hole may be a important person in the focal network and he or she may be the representative person in the focal subgroup in the network. Thus, his or her characteristics may represent the general characteristics of the users in the focal subgroup. In this sense, we can distinguish friends and strangers of the focal user utilizing the structural hole analysis. This study uses the structural hole analysis to select structural holes in subgroups as an initial seeds for a cluster analysis. First, we gather data about users' preference ratings for items and their social network information. For gathering research data, we develop a data collection system. Then, we perform structural hole analysis and find structural holes of social network. Next, we use these structural holes as cluster centroids for the clustering algorithm. Finally, this study makes recommendations using CF within user's cluster, and compare the recommendation performances of comparative models. For implementing experiments of the proposed model, we composite the experimental results from two experiments. The first experiment is the structural hole analysis. For the first one, this study employs a software package for the analysis of social network data - UCINET version 6. The second one is for performing modified clustering, and CF using the result of the cluster analysis. We develop an experimental system using VBA (Visual Basic for Application) of Microsoft Excel 2007 for the second one. This study designs to analyzing clustering based on a novel similarity measure - Pearson correlation between user preference rating vectors for the modified clustering experiment. In addition, this study uses 'all-but-one' approach for the CF experiment. In order to validate the effectiveness of our proposed model, we apply three comparative types of CF models to the same dataset. The experimental results show that the proposed model outperforms the other comparative models. In especial, the proposed model significantly performs better than two comparative modes with the cluster analysis from the statistical significance test. However, the difference between the proposed model and the naive model does not have statistical significance.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.2
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• pp.109-118
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• 2010

This study aims to propose practical strategies for the new urban ideal of regeneration. A book review highlights the emergence of new trends of urbanization in knowledge-information industrial society beyond the new town Ideal of the industrial society. The meaning of ‘landscape’ in landscape urbanism represents not the visual and decorative pictures, but the dynamic process in the context of changes and evolutions. Also, knowledge-information industrial society and landscape have a meaning in the same context of flow and process with changes of velocity. Finally, these key words convey a meaning with the new urban trends of urbanization in knowledge-information industrial society in the context of value-oriented characteristics of dynamics and process. Urban regeneration is emerging as the new urban ideal in the knowledge-information industrial society, beyond the new town ideal of industrial society. It is in the same context as landscape urbanism with respect to green infrastructure buildings and designs for the transformation of urban surfaces covered with concrete and asphalt into the ecological surface, and of the ecological surfaces into the cultural surface that could be communicated with human beings. This research revealed the six strategies for urban regeneration as follows. The First, the strategies for the transformation of urban surfaces into ecological surfaces, the second, the strategies for the transformation of ecological surfaces into cultural surfaces, the third, the introduction of mixed and convergence land use, the forth, the transformation of former sites(e.g. military and factory) into urban parks, the fifth, the introduction of waterfront park zones that have the function of ecological and park-oriented mixed land use and, the sixth, the building and design of green infrastructure in the residential and commercial complex in CBD. These strategies call for the reforms of development laws and regulations to restrict building coverage ratio, building heights, and the introduction of park-oriented mixed zoning regulations. Another method for implementating the above listed strategies was the introduction of a strategic planning system instead of the traditional master plan system. This system uses a value planning approach and brand making by imagery. It is able to construct the meaning of an image and its creativeness directly.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.1
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• pp.1-8
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• 2013

This study was conducted to compare the local climate conditions and growth periods for the apple (Malus domestica 'Borkh') orchards at different altitudes (330, 500, and 670 m) in Jangsu-Gun, Korea. Observation data for the growth period show that the monthly mean air temperatures at the 'Hongro' apple orchard sites decrease with height at the rate of 1.0 to $3.0^{\circ}C$/100 m. The monthly minimum temperatures in April (blooming period for 'Hongro' apple) were 4.3, 2.9, and $0.4^{\circ}C$ at 330, 500, and 670 m, respectively. The monthly mean temperatures in September (i.e., the coloration and maturation period) were 20.6, 18.7, and $14.5^{\circ}C$, respectively. The annual precipitation range varied from 1,234 to 1,439 mm, which tended to increase with height. The heavy rainfall occurred in summer (June to August) and amounted to 827-933 mm. No significant differences in the duration of sunshine were observed amongst the orchards at three different altitudes. The earliest bud break was observed at the 330 m altitude (18 March 2009), which was 4 and 11 days earlier in comparison to those at 500 and 670 m, respectively. The time of full bloom at 330 m was 12 days ahead of that at 670 m. The optimal maturation of fruit (based on skin redness > 80%) was observed between 7 and 10 September at 330 m, 15 and 18 September at 500 m, and 21 and 23 September at 670 m.