• Journal of the Mineralogical Society of Korea
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• v.32 no.4
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• pp.273-285
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• 2019

This study is aimed to interpret the raw material characteristics and manufacturing technology through physical, mineral and geochemical analysis of the brown-glazed stonewares and roof tiles excavated from the Hong Nang Sida temple in Laos, which was built in the 12th century. The glaze of brown-glazed stoneware is a typical lime serial with CaO content of more than 15 % and they were vitrified. The body is the combination of quartz, mullite and cristobalite, but had not vitrified texture, and therefore, which is assumed to have been fired more than 950 ℃. Meanwhile, The roof tiles are unglazed and its outer color is reddish brown, whitish grey and bluish grey. The bluish gray tiles has sandwich structure, which seem to experience imperfect reducing environment. The tile samples with a number of amorphous iron oxide nodule had a very similar chemical composition. In conclusion, it is assumed that the clay source was made from raw material produced from the same bedrock. The firing temperature of roof tiles were divided into less than 900 ℃, 900~950 ℃ and greater than 950 ℃ according to detection of micas, hercynite and mullite.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.479-483
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• 2014

The area of greenhouse horticulture has increased dramatically since the early 1990s in Korea. However, area per farmer still very small and diverse pest species occurs in greenhouse abundantly because of its protected condition. To manage pests, farmers use many pesticides frequently. Incessant and improper use of chemicals provoked pesticide resistance in pest and poisoning of farmers. In this study, we investigated the efficiencies of automatic dry fog sprayer for controlling two aphid species, Aphis gossypii and Myzus persicae, in greenhouse horticulture. When doors and side windows were completely closed in automatic dry fog sprayer treatment greenhouse, aphids were controlled similar level with conventional spraying method (percent control: 61.0~94.1%). However, when half of the doors and side windows of the greenhouse were opened, aphids were controlled poorly (percent control: 36.0~54.4%).

• Korean Security Journal
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• no.26
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• pp.29-58
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• 2011

Since 11 September 2001, warnings of risk in the nexus of terrorism and nuclear weapons and materials which poses one of the gravest threats to the international community have continued. The purpose of this study is to analyze the aim, principles, characteristics, activities, impediments to progress and developmental recommendation of the Global Initiative to Combat Nuclear Terrorism(GICNT). In addition, it suggests implications of the GICNT for the ROK policy. International community will need a comprehensive strategy with four key elements to accomplish the GICNT: (1) securing and reducing nuclear stockpiles around the world, (2) countering terrorist nuclear plots, (3) preventing and deterring state transfers of nuclear weapons or materials to terrorists, (4) interdicting nuclear smuggling. Moreover, other steps should be taken to build the needed sense of urgency, including: (1) analysis and assessment through joint threat briefing for real nuclear threat possibility, (2) nuclear terrorism exercises, (3) fast-paced nuclear security reviews, (4) realistic testing of nuclear security performance to defeat insider or outsider threats, (5) preparing shared database of threats and incidents. As for the ROK, main concerns are transfer of North Korea's nuclear weapons, materials and technology to international terror groups and attacks on nuclear facilities and uses of nuclear devices. As the 5th nuclear country, the ROK has strengthened systems of physical protection and nuclear counterterrorism based on the international conventions. In order to comprehensive and effective prevention of nuclear terrorism, the ROK has to strengthen nuclear detection instruments and mobile radiation monitoring system in airports, ports, road networks, and national critical infrastructures. Furthermore, it has to draw up effective crisis management manual and prepare nuclear counterterrorism exercises and operational postures. The fundamental key to the prevention, detection and response to nuclear terrorism which leads to catastrophic impacts is to establish not only domestic law, institution and systems, but also strengthen international cooperation.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.485-490
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• 2014

This study was conducted to assess the occurrence and damages by thrips on greenhouse-cultivated fig in Hwaseong, Gyeonggi Province, Korea. We identified the collected species as Thrips tabaci Lindeman, Frankliniella occidentalis Pergande, and F. intonsa Trybom. The density of thrips in the greenhouses during the summer months was monitored using yellow sticky traps; T. tabaci showed the highest density, followed by F. occidentalis and F. intonsa. The damages by thrips were characterized by stunted plant growth because of delayed discoloration of the pericarp, and development of rough fruit surface. Stereomicroscopic observation on the fruit flesh revealed the growth of gray mold at the damaged area, as well as the dead bodies and exuviae of thrips. The rates of fig fruit damages per month, were 18.2%, 9.7%, 2.9%, and 1.3% in July, August, September, and October, respectively.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.2
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• pp.69-83
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• 2018

The South China Sea (SCS) is a typical marginal sea characterized with the deep basin, shelf break, shallow shelf, many straits, and complex bathymetry. This study investigated the tidal characteristics and propagation, and reproduced typhoon-induced storm surge in this region using the regional real-time tide-surge model, which was based on the unstructured grid, resolving in detail the region of interest and forced by tide at the open boundary and by wind and air pressure at the surface. Typhoon Haiyan, which occurred in 2013 and caused great damage in the Philippines, was chosen as a case study to simulate typhoon's impact. Amplitudes and phases of four major constituents were reproduced reasonably in general, and the tidal distributions of four constituents were similar to the previous studies. The modelled tide seemed to be within the acceptable levels, considering it was difficult to reproduce the tide in this region based on the previous studies. The free oscillation experiment results described well the feature of tide that the diurnal tide is prevailing in the SCS. The tidal residual current and total energy dissipation were discussed to understand the tidal and sedimentary environments. The storm-surge caused by typhoon Haiyan was reasonably simulated using this modeling system. This study established the regional real-time barotropic tide/water level prediction system for the South China Sea including the seas around the Philippines through the validation of the model and the understanding of tidal characteristics.

• Ocean and Polar Research
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• v.32 no.3
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• pp.213-228
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• 2010

In late 2010, the Korea Hydrographic and Oceanographic Administration proposed a national monitoring project involving the deployment of 8 realtime ocean data buoys. The area occupied by the buoy-array, located south of the Ieodo Ocean Research Station, can be regarded as a kind of gateway to Korean waters with respect to warm currents and the shipping industry. The acronym for the project, KOGA (Korea Ocean Gate Array) was derived from this aspect. To ensure the success of the project, international cooperation with the neighboring countries of China and Japan is highly desirable. Once KOGA is successfully launched and the moored buoys start to produce data, the data will be applied to various areas such as data assimilation for operational oceanography, circulation dynamics, biogeochemical studies, satellite observations, and air-sea interactions. The aim of this paper is to provide suggestions for KOGA planning and applications.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.89-103
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• 2013

National demands for the ocean forecasting system have been increased to support economic activity and national safety including search and rescue, maritime defense, fisheries, port management, leisure activities and marine transportation. Further, the ocean forecasting has been regarded as one of the key components to improve the weather and climate forecasting. Due to the national demands as well as improvement of the technology, the ocean forecasting systems have been established among advanced countries since late 1990. Global Ocean Data Assimilation Experiment (GODAE) significantly contributed to the achievement and world-wide spreading of ocean forecasting systems. Four stages of GODAE were summarized. Goal, vision, development history and research on ocean forecasting system of the advanced countries such as USA, France, UK, Italy, Norway, Australia, Japan, China, who operationally use the systems, were examined and compared. Strategies of the successfully established ocean forecasting systems can be summarized as follows: First, concentration of the national ability is required to establish successful operational ocean forecasting system. Second, newly developed technologies were shared with other countries and they achieved mutual and cooperative development through the international program. Third, each participating organization has devoted to its own task according to its role. In Korean society, demands on the ocean forecasting system have been also extended. Present status on development of the ocean forecasting system and long-term plan of KMA (Korea Meteorological Administration), KHOA (Korea Hydrographic and Oceanographic Administration), NFRDI (National Fisheries Research & Development Institute), ADD (Agency for Defense Development) were surveyed. From the history of the pre-established systems in other countries, the cooperation among the relevant Korean organizations is essential to establish the accurate and successful ocean forecasting system, and they can form a consortium. Through the cooperation, we can (1) set up high-quality ocean forecasting models and systems, (2) efficiently invest and distribute financial resources without duplicate investment, (3) overcome lack of manpower for the development. At present stage, it is strongly requested to concentrate national resources on developing a large-scale operational Korea Ocean Forecasting System which can produce open boundary and initial conditions for local ocean and climate forecasting models. Once the system is established, each organization can modify the system for its own specialized purpose. In addition, we can contribute to the international ocean prediction community.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.337-348
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• 2012

The Yellow Sea Ecoregion Conservation Project is a joint international project which is carried out under the purposes of conserving the habitats in the Yellow Sea Ecoregion and biodiversity from various threats that damage ecosystems, informing the importance and value of the Yellow Sea Ecoregion, and promoting the understanding and interests of Korea, China and Japan. Subsequent to the Yellow Sea Ecoregion Planning Programme which had been performed during the period from 2002 to 2006, the Yellow Sea Ecoregion Support Project has been performed over 7 years in total from 2007 to 2014. Panasonic is sponsoring the financing of the project, and the organizations in charge of the project by country are Korea Institute of Ocean Science & Technology for Korea and World Wide Fund for Nature branches for China and Japan. While the Yellow Sea Ecoregion Planning Programme was focused on the biological assessment and the selection of potential priority area by scientific review, the Yellow Sea Ecoregion Support Project is oriented toward practical activities targeting more diversified stakeholder. Especially, this project plans to support direct conservation activities in the region and participation and cooperation from local residents. The project plan is comprised of 3 phases. During the first period from 2008 to 2009, small grant projects were operated targeting 16 institutions of Korea and China, and for the second period from 2010 to 2012, one place each was selected as demonstration site for habitat conservation in Korea and China respectively and supported for three years to introduce the conservation method based on international standards such as the management of marine protected areas, ecosystem-based management and community-based management and simultaneously to develop habitat conservation activities suitable for national and regional characteristics. During the period from 2013 to 2014 which is the last phase, the project plans to distribute the performance of small grant projects and demonstration site activities through a series of forums among stakeholder. Through the activities described above, the recognition of general public on the conservation of the Yellow Sea Ecoregion was changed positively, and community-based management began to be reflected in the policies for the marine protected areas of central and local government.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.351-355
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• 2010

This study was conducted to determine the relationship of larval density of tobacco cutworm, Spodoptera litura (Fabricius) to damage in greenhouse sweet pepper. Laboratory experiments, cage experiments by artificial release and field investigation were carried out in 2008. The leaf consumption rate increased greatly with larval development. The damaged leaves had several round or oval shape holes on the surface or lost certain parts of them, and the fruit damaged had a conspicuous hole on the surface or scar marks around the calyx. In the field investigation, fruit damage was highly correlated with larval densities and reached 3.5% damage at maximum. Cage experiments showed that numbers of non-marketable fruit increased as increasing larval densities released. The larval density at two weeks before harvest had a high relationship with the percentage of damaged-fruit at harvest. Corresponding larval density caused 1, 3, 5% of damaged-fruit was 0.2, 0.5, 0.8 larvae per plant, respectively.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.285-294
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• 1994

Some supported gold catalysts were prepared by impregnation and coprecipitation methods. Effect of gold addition and active sloe formation were studied by investigating particle sizes of gold, amounts of oxygen adsorbed, adsorption properties of CO and NO, and reduction and oxidation properties, etc.. The gold particles of the catalyst by impregnation were irregular and very large as 30~100 nm, but those by coprecipitation were uniform and ultra-fine as about 4 nm. On $Au/Al_2O_3$ catalyst, the addition of gold to inactive $Al_2O_3$ caused the decomposition of $N_2O$, and CO was not irreversibly adsorbed while $O_2$ was atomically and irreversibly adsorbed. The adsorption sites of oxygen were attributed to the active sites which were restricted to the circumference of hemispherical gold particle-support interface rather than all atoms on the surface of gold particle. Also, CO was reversibly and irreversibly adsorbed on $Al_2O_3$ at low temperature, and the addition of gold weakened both reversible and irreversible adsorptions. The affinity for CO on $Au/Co_3O_4$ catalyst decreased conspicuously compared to $Co_3O_4$. The effect of gold addition did not appear in reduction step but did remarkably in reoxidation step; the added gold promoted the reoxidation of the reduced cobalt atoms.