• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.2
• /
• pp.88-97
• /
• 2009

This study was conducted to obtain the basic information to increase the practical use of soil survey data through the subdividing of lava shapes with soil sequences due to different elevations in Jeju. The numbers of soil series of lava topography had occupied many of whole soil series in Jeju. When its topography subdivide, it give more detailed soil information. The obtained results are as follows; The lava topography to subdivide lava topography were studied with 38 soil series according to elevation in Jeju. Division of elevation are less than 50m, 50m to 200m, and 200m to 400m and more than 400m. Name the depending on elevation, less than 50m is called lower part of lava, 50m to 200m is called middle part of lava, and 200m to 400m and more than 400m are called upper part of lava. The characteristics of lava subdivide are as follows; soil family texture of lower part of lava is fine silty to clayey, drainage classes are various, average of available soil depth is 75.3cm, average of gravely contents are 11.6%, average of slopeness is 7.2%, limiting factor are various and soil order are various. soil family texture of middle part of lava is fine silty to coarse silty, drainage classes are well to very well, average of available soil depth is 65.9cm, average of gravely contents are 14.7%, average of slopeness is 11.3%, limiting factor are ashy and soil order are Andisols and Inceptisols. Soil family texture of upper part of lave is fine silty, drainage classes are well, average of available soil depth is 72.8cm, average of gravely contents are 16.0%, average of slopeness is 14.9%, limiting factor are ashy and skeletal, and order are Andisols.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.1
• /
• pp.36-44
• /
• 2010

In order to rehabilitate forest sites damaged by wildfire via natural or artificial restoration, it is important to determine right tree species, which can acclimate to biogeoclimatic environment at the sites. The objectives of this study were to develop site index equation of different tree species for estimating forest productivity and to provide information on species selection for post-wildfire restoration. Site index equation was developed based on environmental information from wildfire damaged areas in Gangneung, Goseong, Donghae, and Samcheok, where were located in east coastal areas of South Korea. Despite the small numbers (4~5) of environmental variables used for the development of the site index equations, statistical analysis (e.g. mean difference, standard deviation of difference, and standard error of difference) showed relatively low bias and variation, suggesting that those equations can provide relatively high capability of estimation and practical applicability with high effectiveness. The small numbers of the variables enabled the model to be applied in a wide range of usages including determination of appropriate tree species for post-wildfire restoration. The estimation of forest site productivity showed the possibility of large distribution in east coastal region as the best site for Korean ash (Fraxinus rhynchophylla) and original oak (Quercus variabilis) that can be used for firebreak in the region. These results imply that damages by forest fire can be reduced significantly by replacing existing pure coniferous forests in the area with ones dominated by broad-leaved deciduous stands, which can play an important role as fire break and/or prevent a transition from surface fire to crown fire.

• Journal of Korean Society for Geospatial Information Science
• /
• v.23 no.1
• /
• pp.101-111
• /
• 2015

Stream restoration projects have become threats to riparian ecosystem in Rep. of korea. Riparian wildlife becomes isolated and the animals are often experience difficulties in crossing riparian corridors. The purposes of this study is to select suitable wildlife passages for wild animals crossing riparian corridors. Maximum entropy model and snow tracking data on embankment in winter seasons were used to develop species distribution models to select suitable wildlife passages for water deer. The analysis suggests the following. Firstly, most significant factors for water deer's habitat in area nearby riparian area are shown to distance to water, age-class, land cover, slope, aspect, digital elevation model, tree density, and distance to road. For the riparian area, significant factors are shown to be land cover, size of riparian area, distance to tributary, and distance to built-up. Secondly, the suitable wildlife passages are recommended to reflect areas of high suitability with Maximum Entropy model in riparian areas and the surrounding areas and moving passages. The selected suitable areas are shown to be areas with low connectivity due to roads and vertical levee although typical habitats for water deer are forest, grassland, and farmland. In addition, the analysis of traces on snow suggests that the water deer make a detour around the artificial structures. In addition, the water deer are shown to make a detour around the fences of roads and embankment around farmland. Lastly, the water deer prefer habitats around riparian areas following tributaries. The method used in this study is expected to provide cost-efficient and functional analysis in selecting suitable areas.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.4
• /
• pp.241-263
• /
• 2010

KoFlux is a Korean network of micrometeorological tower sites that use eddy covariance methods to monitor the cycles of energy, water, and carbon dioxide between the atmosphere and the key terrestrial ecosystems in Korea. KoFlux embraces the mission of AsiaFlux, i.e. to bring Asia's key ecosystems under observation to ensure quality and sustainability of life on earth. The main purposes of KoFlux are to provide (1) an infrastructure to monitor, compile, archive and distribute data for the science community and (2) a forum and short courses for the application and distribution of knowledge and data between scientists including practitioners. The KoFlux community pursues the vision of AsiaFlux, i.e., "thinking community, learning frontiers" by creating information and knowledge of ecosystem science on carbon, water and energy exchanges in key terrestrial ecosystems in Asia, by promoting multidisciplinary cooperations and integration of scientific researches and practices, and by providing the local communities with sustainable ecosystem services. Currently, KoFlux has seven sites in key terrestrial ecosystems (i.e., five sites in Korea and two sites in the Arctic and Antarctic). KoFlux has systemized a standardized data processing based on scrutiny of the data observed from these ecosystems and synthesized the processed data for constructing database for further uses with open access. Through publications, workshops, and training courses on a regular basis, KoFlux has provided an agora for building networks, exchanging information among flux measurement and modelling experts, and educating scientists in flux measurement and data analysis. Despite such persistent initiatives, the collaborative networking is still limited within the KoFlux community. In order to break the walls between different disciplines and boost up partnership and ownership of the network, KoFlux will be housed in the National Center for Agro-Meteorology (NCAM) at Seoul National University in 2011 and provide several core services of NCAM. Such concerted efforts will facilitate the augmentation of the current monitoring network, the education of the next-generation scientists, and the provision of sustainable ecosystem services to our society.

• Journal of Food Hygiene and Safety
• /
• v.33 no.5
• /
• pp.361-368
• /
• 2018

N-nitrosamines are probable or possible human carcinogens, which are produced by the reaction between secondary amines and nitrogen oxide in the acidic environment or by heating. Common risk assessment procedure involves the comparison between exposures expressed in the unit, mg/kg body weight/day and the Health-Based Reference dose expressed in the same unit. This procedure is suitable for the policy decision-making and is considered as inappropriate for the consumers to get information about their dietary decision-making. Therefore, the distributions of NDMA (N-nitrosodimethylamine), NDBA (N-nitrosodibutylamine), the six N-nitrosamines (NDMA, NDBA, NDEA (N-nitrosodiethylamine), NPYR (N-nitrosopyrrolidine), NPIP (N-nitrosopiperidine), and NMOR (N-nitrosomorpholine) in the menus grouped based on the presence of main ingredients and cooking methods were analyzed to generate consumer-friendly information regarding food contaminants. Recipes and intakes were taken from 2014 to 2016 KNHANES (The Korean National Health and Nutrition Examination Survey) and only the data from ages of 7 years or older were used. The contamination data were collected from the 2014~2016 Total Diet Study and all the analysis were performed using R software. Rockfish, eel, anchovy broth and pollock were mainly exposed to N-nitrosamines. In terms of cooking methods, soups and stews appeared to contain the highest amount of N-nitrosamines. Cereals, fruits, and dairy products in the ingredient categories, and rice dishes and rice combined with others in recipe categories had the lowest level exposure to N-nitrosamines. In case of N-nitrosamines, unlike other cooking related food contaminants, boiled dishes such as soups and stews and dishes mainly consisting of fishes and shellfishes had highest level of exposure, showing a large discrepancy with the previous thought of processed meat is the main source of N-nitrosamines.

• Journal of Korea Society of Industrial Information Systems
• /
• v.23 no.5
• /
• pp.119-134
• /
• 2018

Today, many firms face the environment of high uncertainty and severe competition due to the rapid technology development and the diverse needs of customers. In the business environment, one of the most important ways to gain sustainable competitive advantage and future growth engine is related to NPD (New Product Development), which is a very important issue for practice and academia. Thus, this study intends to provide new values to practitioners and researchers related to NPD by analyzing current research trends and future trends in NPD field. For this, we bibliometrically analyzed keyword networks which consist of keywords that were already published in the eminent journals from Scopus database to generate insights that have not been captured in the previous reviews on the topic. As a result, we could understand the extant research streams in NPD field, and suggest the changes of specific research topics based on the connected relationships among keywords over the time. In addition, we also foresaw the general future research trends in NPD field based on the keywords according to preferential attachment processes. Through this study, it was confirmed that NPD keyword network is a small world network that follows the distribution of power law and the growth of network is formed by link formation by keyword preferential attachment. In addition, through component analysis and centrality analysis, keywords such as Innovation, New product innovation, Risk management, Concurrent engineering, Research and development, and Product life cycle management are highly centralized in NPD keyword network. On the other hand, as a result of examining the change of preferential attachment of keywords over the time, we suggested the required new research direction including i) NPD collaboration with suppliers, ii) NPD considering market uncertainty, iii) NPD considering convergence with the other academic areas like technology management and knowledge management, iv) NPD from SME(Small and medium enterprises) perspective. The results of this study can be used to determine the research trends of NPD and the new research themes for interdisciplinary studies with other disciplines.

• Journal of Oral Medicine and Pain
• /
• v.34 no.1
• /
• pp.63-79
• /
• 2009

While previous epidemiological studies on temporomandibular disorders (TMD) have been based on a given health center or population sample, no study has been performed on general population of Korea, especially concerning about treatment pattern such as clinician’s specialty involved in TMD treatment, types and amount of prescription medication and cost. This study aimed to investigate magnitude of health visits and treatment patterns for Korean patients with TMD through the computerized database of Health Insurance Review and Assessment Service (HIRAS). Inclusion criteria were all patients registered on the HIRAS database over 3 years' period from 2003 to 2005 and the medical records of patients with TMD as a main diagnosis were extracted. Information collected was as follows; distribution related to gender, age and region and type of hospital the patients visited, treatment duration, clinicians' specialty involved in treatment, cost, types of prescription medication and surgical treatment. The results of this study indicated that 0.15% of the population yearly sought TMD treatment, presenting with increase of incidence over the three years. Most of TMD patients were women (99.8%) and the biggest age group was second and third decades and decreased with age. Seoul and Kyeonggi province presented with higher incidence of TMD compared to the other regions of Korea, which seems to be related with magnitude of population. 56% of TMD patients visited primary care sector and the numbers of treatment visits was the highest in dental clinic (38.4%), followed by orthopedics (28%) and ENT (13.6%) clinics in order. Duration of prescription medication was the longest for anti-inflammatory analgesics, followed by antipsychotic drugs and muscle relaxants. Inpatient care related to TMD was primarily performed in dental hospital compared to medical hospital. Medical database of HIRAS provided comprehensive and vast information on epidemiologic characteristics and treatment patterns for patients seeking TMD treatment, which can be more reliable data to expect medical demand for TMD in condition that accurate diagnosis and standardized treatment is delivered in clinical settings.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.18 no.2
• /
• pp.95-100
• /
• 2012

This study was determined to analysis marine environmental and phytoplankton monitoring in Wando coastal waters in August during the period of 2009-2010 and provided the basic environmental data against Southwest Sea of Korea. In August, 2009, the distribution of water temperature and salinity showed an unique characteristics for all of stations, which was associated with a long duration of rainfall after July, 2009 and a lack of sunshine. In the lower of August, 2010, the stratification of water temperature and salinity was shown, which was caused by an intensive sunshine after the middle of August, 2010. Gangjin Bay and Gogeundo waters showed a highly different water temperature and transparency. It is thought that two regions have a distinct water mass and characteristics. In dissolved oxygen and oxygen saturation were higher according to higher water depth regardless of stations. In August, 2009, different dominant species occurred that Gangjin Bay showed a higher cell density of diatom, but Gonyaulax polygramma played an important role in dominant species in Gogeundo waters. It is associated with the introduction red tide water of G. polygramma occurring to southern coastal water in August, 2009. In August, 2010, diatom was extremely higher cell density compared with that of dinoflagellate that regarded as adaptive microrganism against higher quantity of suspended solid in Wando waters. Although Wando has a record of Cochlodinium red tide, this species may be difficult to grow and persist. Dominant species, diatom, play an important role in food organism for shellfish and forming a ecological lineage.

• Korean Journal of Environment and Ecology
• /
• v.29 no.6
• /
• pp.850-857
• /
• 2015

This study was aimed to identify the characteristics of nest and breeding site conditions of Chinese Egret (Egretta europhotes) that breed in the uninhabited islets of the western coast of South Korea. It is expected that the information collected through this study can contribute to providing basic information required when building and managing artificial nests in their natural breeding habitats. Chinese Egrets make their nests in the shrub layers of Long Leaf Elaeagnus (Elaeagnus macrophylla), Arrow Bamboo (Pseudosasa japonica), and Baby Brier (Rosa multiflora). A total of 50 breeding nests of Chinese Egret were investigated in June and July 2013, with area-wise distribution as follows: Seomando (11 nests), Hwangseodo (14 nests), Mokdo (10 nests), and Napdaekiseom (15 nests). Vegetation coverage (cover, %), height from the ground to the top (height, cm), thickness from top to bottom of the nest (thickness, cm), reuse period, major axis (cm), minor axis (cm), and depth (cm) of each nest were measured. According to the results of the study on the nest characteristics of 4 breeding groups, the nests in Hwangseodo had the highest coverage, the nests in Mokdo were built in the highest places, the nests in Napdaekiseom showed the longest reuse period, and the nests in Mokdo had the greatest depth. The differences in height and reuse period were significant between Mokdo and Napdaekiseom. Moreover, there were significant differences in reuse period and depth between Seomando and Hwangseodo. There were significant differences in cover, minor axis, and depth between breeding groups that built nests on Arrow Bamboo (Mokdo and Napdaekiseom) and Baby Brier (Seomando and Hwangseodo). Nest characteristics of Chinese Egret were generally similar, while some variables showed different values for different breeding groups.

• Journal of the Korean earth science society
• /
• v.21 no.4
• /
• pp.408-422
• /
• 2000

Multiple geophysical methods were applied over the Manjang cave area in Cheju Island to compare and contrast the effectiveness of each method for exploration of underground cavities. The used methods are gravity, magnetic, electrical resistivity and GPR(Ground Pentrating Radar) survey, of which instruments are portable and operations are relatively economical. We have chosen seven survey lines and applied appropriate multiple surveys depending on the field conditions. In the case of magnetic method. two-dimensional grid-type surveys were carried out to cover the survey area. The geophysical survey results reveal the characteristic responses of each method relatively well. Among the applied methods, the electric resistivity methods appeared to be the most effective ones in detecting the Manjang Cave and surrounding miscellaneous cavities. Especially, on the inverted resistivity section obtained from the dipole-dipole array data, the two-dimensional distribution of high resistivity cavities are revealed well. The gravity and magnetic data are contaminated easily by various noises and do not show the definitive responses enough to locate and delineate the Manjang cave. But they provide useful information in verifying the dipole-dipole resistivity survey results. The grid-type 2-D magnetic survey data show the trend of cave development well, and it may be used as a reconnaissance regional survey for determining survey lines for further detailed explorations. The GPR data show very sensitive response to the various shallow volcanic structures such as thin spaces between lava flows and small cavities, so we cannot identify the response of the main cave. Although each geophysical method provides its own useful information, the integrated interpretation of multiple survey data is most effective for investigation of the underground caves.