• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1266-1269
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• 2004

The introduction of invasive marine species into new environments by ship's ballast water, attached to ships' hulls and via other vectors has been identified as one of the four greatest threats to the world's oceans by Global Environment Facility (GEF). EMO (International Maritime Organization) is carrying out the international restriction of the effluence suppression and treatment of Ship's ballast water by Ballast Water Management Convention. In this paper, to deal with this international restriction convention and to consider economic potential of ship's ballaster treatment market near future, the equipment and technology of ship's ballaster water treatment was studied.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.391-396
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• 2005

Salt water spray test and salt water immersion test were experimentally conducted in order to investigate the durability of fiber reinforced composites under salt water environment. The specimens were made of glass fabric reinforcement and phenolic resin. Mechanical test was performed to obtain mechanical properties such as tensile properties, flexural properties, and shear properties by varying with exposure times. Also dynamic mechanical test and FTIR were conducted to investigate a change in chemical structure as well as thermal analysis properties such as storage shear modulus, loss shear moduls, and tan ${\delta}$. According to the results, salt water environment has effected on mechanical properties and thermal analysis properties and especially the durability of glass fabric/phenolic composites were severely affected on salt water immersion environment rather than salt water spray environment.

• Journal of Environmental Science International
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• v.31 no.12
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• pp.1027-1038
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• 2022

The intertidal zone has both land and marine characteristics and shows complex weather environments. These characteristics are suited for studying climate change, energy balance and ecosystems, and may play an important role in coastal and marine weather prediction and analysis. This study was conducted at Odo Island, approximately 300m from the mainland in Yeosu. We built a weather observation system capable of real-time monitoring on the mud flat in the intertidal zone and measured actual weather and marine data. Weather observation was conducted from April to June 2022. The results showed changes in air temperature and water temperature with changes in the tide level during spring. Correlation analysis revealed characteristic changes in air temperature and water temperature during the day and night, and with inundation and exposure.

• Journal of Korean Medical classics
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• v.27 no.3
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• pp.47-66
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• 2014

Objectives : Evaluating water and its comparisons to Yin(陰) and Yang(陽). In this section, we will look into this matter from Dongeuibogam(東醫寶鑑) and introduce an oriental perspective on the subject of water(水部). Methods : Translating Eumchanboksikjeon(飮饌服食牋) from Junsangpaljeon(遵生八牋). An in depth study of related contents and comparing to the water section(水部) of Dongeuibogam(東醫寶鑑) Results : According to the section of Varieties of Teas and Water(茶泉類) in The Discussion of Springs(論泉水), Goryum(高濂) divided water into five different types in Eumchanboksikjeon(飮饌服食牋) of Junsangpaljeon(遵生八牋). These different types are Water that runs between rocks, Clear and cold water, Sweet and fragrant water, Spiritual water and Well water. Dongeuibogam(東醫寶鑑) also analyzed 28 different types of water out the 33 its list. The idea is that one must use water differently according its origins, where it originated, when and what season to maximize the usage of the water because the energy of water would be different. Conclusions : By evaluating water, we have learned that water picks up energy and changes according to its surrounding environments. The different types of water used changes the medicinal ingredients and it affects the human body differently. One must keep in mind, the cycles of water, its energy and how it helps us live a healthier life.

• Journal of the Korean Home Economics Association
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• v.39 no.9
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• pp.79-93
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• 2001

The purpose of this study is to develop the creative play environments for children. Physical environment is very important for play of child. Play activities of chad depends on materials and resources of physical environment around housing. To achieve the purpose of the study, following research questions are performed: 1) to investigating the play environments and its maintainence in Daejon 2) examining and analyzing the contents, safety, and functions of the playgrounds selected based on above findings 3) suggesting the creating play environments for child. Eighteen playground were selected and evaluated objectively by trainned personnel; the subjects(55children and 39adults) who used the playgrounds evaluated the playground subjectively. The results were as fellows: 1) Playgrounds selected in this study were conventional playgrounds, in which child can only do simple physical activities. The playground has installed fixed equipment in a row, in an effort to utilize whatever space available. However, such places are neither developmentally or economically sound. 2) The playgrounds evaluated in this study were very poor in matter of content, safety, and functions. The playgrounds lacks play materials, equipment, national features, storage, and do not follow national safety guidelines and standards. 3) The playground should offer much wider variety of natural material- textures including grass, dirt, stone, brick, plastic, metal, bark, leaves, sand, water, and a larger variety of plants, gardens, natural areas, and animals.

• Journal of Families and Better Life
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• v.29 no.3
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• pp.71-83
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• 2011

The purpose of this study was to find out the nationwide general characteristics and housing environments of agricultural households and the differences of them by Eup-Myun Areas. The data were subsample of the 2008 survey on the rural living indicators collected by the rural development administration. Only agricultural households, 73.7% of the original nationwide data (1,461 households out of 1,983) sampled by multi-stage stratified clustering methods and face to face interview in Aug. 2008, were selected and the cross-tabulation(X2) was mainly used to find the difference by Eup Myun areas through spss 12.0 for window. The results showed that the general characteristics of agricultural households such as head of household, family, and economic characteristics were mainly differed by Eup Myun Areas. Agricultural households in Eup area were more likely low in the general characteristics than were those in Myun area. Housing environments were less likely than the general characteristics differed by Eup Myun areas. Improvements of drinking water system, housing alteration, oder, and garbage system were needed to increase the satisfaction with residential environments of agricultural households. This study suggests the use of annual survey on the rural living indicators data would be applicable to various research subjects of home economics.

• Journal of Wetlands Research
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• v.7 no.2
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• pp.121-132
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• 2005

To classify the surface sedimentary facies using IKONOS image collected over Hwangdo tidal flat in Cheonsu Bay, the optical reflectance was compared for characterizing various sedimentary environments such as grain size, tidal channel pattern and area ratio of surface remnant water. The intertidal DEM (Digital Elevation Model) was generated by echo-sounder for analyzing the relationship between IKONOS image and sedimentary environments including topography. The boundary of the optical reflectance between mud-mixed facies and sand facies was distinct, and discrimination of the associated sandbar feature was also possible. The mud-mixed facies coupled with intricate tidal channels is confined to the relatively hi호 topography of Hwangdo tidal flat. The boundary between mud and mixed flat was indistinct in IKONOS optical reflectance but it would have a difference in the area ratio of surface remnant water. The dark area in the image represented the well developed sand facies having a lot of surface remnant water due to the relatively low surface topography. The overall accuracy of characterizing the surface sediment facies by maximum likelihood classification method was 86.2 %. These results demonstrate that high spatial resolution satellite imagery such as IKONOS coupled with knowledge of grain size, surface remnant water and tidal channel network can be effectively used to characterize the surface sedimentary facies (mud, mixed and sand) network of the tidal flat environments.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.185-185
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• 2019

Sustaining future wheat production is challenged by anthropogenically forced climate warming and drying led by increased concentration of greenhouse gases all around the globe. Warming stresses, originating from the elevated $CO_2$ concentration, are continuously reported to have negative impacts on wheat growth and yield. Yet, elevated $CO_2$ concentration, despite being disparagingly blamed for promoting warming, is also associated with a phenomenon called $CO_2$ enrichment; in which wheat yield can improve due to the enhanced photosynthesis rates and less water loss through transpiration. The conflicting nature of climate warming and $CO_2$ enrichment and their interplay can have specific implications under different environments. It is established form the field and simulation studies that the two contrasting phenomena would act severely in their own respect under arid and semi-arid environments. Wheat is a dietary staple for masses in Pakistan. The country's wheat production system is under constant stress to produce more from irrigated agricultural lands, primarily lying under arid to semi-arid environments, to meet the rapidly growing domestic needs. This work comprehensively examines the warming impacts over wheat yield and water productivity (WP), with and without the inclusion of $CO_2$ enrichment, under semi-arid environment of Punjab which is the largest agricultural province of Pakistan. Future wheat yields and WPs were simulated by FAO developed AquaCrop model v 5.0. The model was run using the bias-correction climate change projections up to 2080 under two representative concentration pathways (RCP) scenarios: 4.5 and 8.5. Wheat yield and WPs decreased without considering the $CO_2$ enrichment effects owing to the elevated irrigation demands and accelerated evapotranspiration rates. The results suggested that $CO_2$ enrichment could help maintain the current yield and WPs levels during the 2030s (2021-2050); however, it might not withhold the negative climate warming impacts during the 2060s (2051-2080). Furthermore, 10 - 20 day backward shift in sowing dates could also help ease the constraints imposed by climate warming over wheat yields and WPs. Although, $CO_2$ enrichment showed promises to counteract the adverse climate warming impacts but the interactions between climate warming and $CO_2$ concentrations were quite uncertain and required further examination.

• Korean Journal of Materials Research
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• v.21 no.1
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• pp.1-7
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• 2011

Methods of producing hydrogen include steam reforming, electrochemical decomposition of water, and the SI process. Among these methods, the Sulfur iodine process is one of the most promising processes for hydrogen production. The thermochemical sulfur-iodine (SI) process uses heat from a high-temperature-gas nuclear reactor to produce $H_2$ gas; this process is known for its production of clean energy as it does not emit $CO_2$ from water. But the SI-process takes place in an extremely corrosive environment for the materials. To endure SI environments, the materials for the SI environment will have to have strong corrosion resistance. This work studies the corrosion resistances of the Fe-Si, Ni-Ti and Ni Alloys, which are tested in SI-process environments. Among the SI-process environments, the conditions of boiling sulfuric acid and decomposed sulfuric acid are selected in this study. Before testing in boiling sulfuric acid environments, the specimens of Fe-4.5Si, Fe-6Si, Ni-4.5Si, Ni-Ti-Si-Nb and Ni-Ti-Si-Nb-B are previously given heat treatment at $1000^{\circ}C$ for 48 hrs. The reason for this heat treatment is that those specimens have a passive film on the surface. The specimens are immersed for 3~14 days in 98wt% boiling sulfuric acid. Corrosion rates are measured by using the weight change after immersion. The corrosion rates of the Fe-6Si and Ni-Ti-Si-Nb-B are found to decrease as the time passes. The corrosion rates of Fe-6si and Ni-Ti-Si-Nb-B are measured at 0.056 mm/yr and 0.16 mm/yr, respectively. Hastelloy-X, Alloy 617, Alloy 800H and Haynes 230 are tested in the decomposed sulfuric acid for one day. Alloy 800H was found to show the best corrosion resistance among the materials. The corrosion rate of Alloy 800H is measured at -0.35 mm/yr. In these results, the corrosion resistance of materials depends on the stability of the oxide film formed on the surface. After testing in boiling sulfuric acid and in decomposed sulfuric acid environments, the surfaces and compositions of specimens are analyzed by SEM and EDX.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.2
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• pp.105-121
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• 2011

The operation of tidal power facility may induce severe changes of water quality in Shihwa Lake. Current water quality data are quite important to water quality management policy of Shihwa Lake. Thus, the water quality data of Shihwa Lake and its adjacent sea in 2010 were presented to characterize the temporal and spatial changes of water parameters such as pH, SS, DO, COD, dissolved nutrients, chlorophyll-a, TN and TP. Highest levels of water quality parameters were observed near the Shihwa and Banweol industrial complexes and the levels of water quality parameters were on a decreasing trend to those near the water gate. It suggests that the horizontal distributions of water quality levels are mainly controlled by the supply of fresh water from streams and the inflow of outer seawater by operation of water gate. Although the higher concentrations of TN and TP were observed in the location being affected by Sorae port, the levels of water quality parameters in outer sea of Shihwa Lake were lower than those in Lake. In summer season, hypoxic condition was well developed in bottom water by strong stratification and active decomposition of organic matter. Thus, the vertical distributions of dissolved nutrient, TN and TP concentrations showed the concentrations to be higher in bottom seawater than those in surface seawater whereas the vertical distributions of chlorophyll-a, COD and POC concentrations showed the concentrations to be higher in surface seawater than those in bottom water. Results of Pearson's correlation matrix for surface seawater demonstrated that salinity showed negatively good correlation with not only dissolved nutrients except for ammonium but chlorophyll-a, COD and POC This result indicates that the supply of dissolved nutrients through several streams might significantly affect phytoplankton bloom and increase of COD concentration in surface seawater.