• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.523-532
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• 2008

A phase II site investigation and feasibility study was conducted at a military mortar shooting range near the demilitarized zone (Kyunggi, South Korea) to assess the extent of contaminants migration to the nearby Imjin river in which a flood control dam is under construction. The results showed that silty-clay soils around target areas were co-contaminated with heavy metals (Cd, Cu, and Pb) and explosives (HMX, RDX, and TNT). The total amount of contaminant was estimated to be 497.1 kg-RDX, 20.6 kg-HMX, 1.4 kg-TNT, 35.2 kg-Cd, 4,331 kg-Cu, and 5,115 kg-Pb, respectively. Both heavy metals and explosives were almost equally distributed on each soil particle size fraction. Neither subsurface soil samples nor ground water samples showed signs of contamination above the environmental criteria. The major migration route of contaminants was soil particles in surface run-off during rain at which a mass discharge rate of 30.0 mg-RDX/hour was observed.

• Journal of the Korean Graphic Arts Communication Society
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• v.23 no.2
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• pp.143-159
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• 2005

The printing could not expect the print effect of the specific character of a printing material. Specially, a property of the paper that we are aware of the substrate has controled printability as well as run ability. The objective of this study was to measure substrate properties by measuring the water receptivity in order to know the degree of the uniformity on surface of paper. Therefore, the water receptivity was measured by fluid bridge method. And then the physical properties of samples such as ink set-off, porosity and print mottle of domestic coated papers were measured by Tappi method. Accordingly, this study obtained the outcome of water receptivity. And then we could know that the relations between water receptivity and physical properties of the paper samples have correlations. There are many measurement equipments to find out print mottle by the measurement of the reflected density at this point in time. However, it is thought that the fluid bridge method is the most proper way to find out print mottle, though there are many other ways to figure out.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.1
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• pp.27-38
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• 2006

In this study, we developed a program to estimate discharge efficiently considering major hydraulic characteristic including water level, river bed, water slope and roughness coefficient in a natural river. Stream discharge was measured at Gongju gauge station located in the down stream of the Daechung Dam during normal and dry seasons from 2003 to 2004. The developed model was compared with the results from the existing rating curve at T/M gage stations, and was used for runoff analyses. Evaluating the developed river discharge estimation program, it was applied during 1983-2004 that base flow separation method and RRFS (Rainfall Runoff Forecasting System) which is based on SSARR (Streamflow Synthesis And Resevoir Regulation). The result presents the stage-discharge curve creator range at the Gong-ju is overestimated by approximately $10-20\%$, especially at the low stage. It is attributed to the hydraulic characteristics at the study. The discharge simulated by the RRFS and base flow separation, which is calibrated using the measurement at the early spring and late fall season during relatively d]v season, shows the least errors. The coefficient of roughness at Gongju station varied with the high and low water level.

• Journal of Environmental Science International
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• v.10 no.2
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• pp.159-166
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• 2001

We studied the appearance and proliferation of red tide organisms from March, 1998, to February, 1999, in the Jindong Bay. There were two red tide events during investigation, and we found that the dominant species Ceratium furca in May and Gymnodinium sanguineum in September, 1998. At surface, temperature and salinity showed 18.3~19.7$^{\circ}C$ and 30.6~30.9 psu in May and 25.6~27.$0^{\circ}C$, 28.0~28.5 psu in September, respectively. When the red tide occurred, the water mass stable. Dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphate(DIP) in Jindong Bay showed seasonal variability. In May, the nitrogen was a limited nutrient in which the ratio of DIN versus DIP was less than 16 (Redfield ratio), while in September phosphate. During June to September, 1998, phosphate acted as a limited nutrient due to the increased river run-off from land. In May, chlorophyll-a, dissolved oxygen(DO) and chemical oxygen demand(COD) showed higher than 20$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 5.0mg/$\ell$, respectively. In September, they showed in turns 100$\mu\textrm{g}$/$\ell$, 10mg/$\ell$ and 10mg/$\ell$, respectively.

• Journal of Technologic Dentistry
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• v.18 no.1
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• pp.39-65
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• 1996

The purpose of this to inquire of the people who run a dental mechanical laboratory having troubles to manage and to find out the reform measures on the point at issue. With having done random sampling for the chiefs of dental mechanical labs across the nation, and then marking the analysis of the data for the survey, I came to a conclusion to be as follow. 1. The operating problems in dental mechanical laboratory in Korea is that it is too near at hand that the requested days for the manufacture of dental prosthesis appliances form dental clinics(45%)(P<0.01) 2. The problem of dental mechanic manpower was due to a small salary and inferior working environment(35% each)(P<0.01) 3. Some of them discount dental mechanical charges in manufacturing dental prosthesis appliances(36.7%)(P<0.01) 4. Many of them employed unlicensed dental technicians(61.7%)(P<0.01) As a counterplan for the aforementioned, I think that the whole dental mechanics should cooperate in breaking off the customary custom to allow a discount on the dental mechanical charges and readjust the dental mechanical charge to a realistic level so as to contribute to the development of the dental mechanical community and the vetterment of the public oral hygience.

• Korean Institute of Interior Design Journal
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• v.17 no.2
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• pp.91-101
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• 2008

The purpose of this study is to suggest the design guidelines of exhibition space for conservation of collection in a museum. With the purpose of this study, examined the concept and a condition of conservation which is focused on deterioration in a exhibition space, investigated the actual condition of total 42 facilities and analyzed the specific instance which is excellent by factor of environment plan. Hereupon, the results of this study are as follows. First, exhibition space should be equipped with sufficient 'Filtering Space' before the outdoor and located central territory in a museum facility. Second, exhibition space should be partition off an area into the quality of collection, and then controlled by each of them. Third, in consideration of the annual air fluctuation of our country, the database which is adaptable for setting up the standard of temperature and RH must be prepared. Fourth, it is necessary to establish a 'Reference Exhibition Room' which is formed cellular type and a 'Garnering Exhibition Center'. Fifth, for the prevention of deterioration which is generated in exhibition space, the showcase must be high air-tight. Sixth, it is necessary to reduce a inside space of high air-tight showcase. Seventh, art-sorb is suitable for control the organic matter of collection and a except of fiber optics is not suitable for lighting of showcase. Eighth, wall-type showcase should be have air-chamber which is formed like museum storage and run over 8 hours a day.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.5 no.3
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• pp.187-197
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• 1993

In this study, the numerical analysis and experiments of the hot water storage using the thermal stratification techniques were carried out. The CPU time for a typical run of the the thermal stratification up to 900 seconds took one week for a $81{\times}31$ mesh size and 10 days for a $118{\times}31$ mesh size, respectively, for a cylindrical shape of the storage. In the initial stage, the numerical results were in favorable agreement with the experimental results, but it showed that the temperature gradients in the storage decreased gradually with time. It was also found that the increase of ${\delta}t$ decreased the convergent speed due to the intensive fluctuation of the velocity field in every iteration. The increase of numbers of grids is projected to forecast a more accurate result, but it made the computing time longer and woul slow down convergence. At the experiments of the flow visualization, it was confirmed that the thermal stratification was apparently built up due to the installation of diffuser at the lower part of the storage. Thus, the thermal performance of the storage could be improved by installing the diffusers at the inlet and outlet.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.6
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• pp.33-38
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• 2011

In recent years, mobile devices and high-hearth because of the multi-functional, battery usage is increasing. But compared to the required computing power increases the battery's energy capacity of the research is going slowly. In this paper we use the battery discharge characteristics, can be used in battery research and to increase the effective capacity, wireless transmission of power from the system just by turning off the technology to extend battery life is explained. Experimental transmission of images through the standard battery drain intervals according to measuring battery life, and applications used in these experiments and heuristic to optimize battery run time was achieved.

• Asia-Pacific Journal of Business
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• v.6 no.1
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• pp.27-43
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• 2015

The objective of the present study is to identify the security factors that influence customer trust towards intention to continue using Internet banking in Malaysia. The participants are individual Internet banking users in Peninsular Malaysia. Data was collected through self-administered questionnaires distributed using the drop-off and pick-up (DOPU) technique to bank branch managers who then passed the questionnaires to their customers. A total of 413 respondents completed the questionnaires. The SPSS statistical analysis software package and Partial Least Squares statistical method were used for data analysis and hypothesis testing. The results show that authentication, confidentiality, data integrity and non-repudiation are significant factors that influence customer trust towards intention to continue using Internet banking. Trust plays a critical role in influencing the intention to continue using Internet banking in Malaysia while perceived privacy does not. An understanding of the factors identified in this study will enable Internet banking providers to effectively and efficiently enhance the security of services and thereby promote continued usage of Internet banking among customers. The findings of this study are thus expected to be of great use to Internet banking providers as improvements in Internet banking security will increase business in the long run.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.277-283
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• 2010

Research on permeable pavement like asphalt and concrete pavement with porous structure has been increasing due to environmental and functional need such as reduction of run off and flood. This study was performed to evaluate void ratio, permeability coefficient, and compressive strength of permeable polymer concrete (PPC) using crushed and recycled coarse aggregate that is obtained from waste concrete. Also, 6 mm length of polypropylene fiber was used to increase toughness and interlocking between aggregate and aggregate surrounded by binder. Binder and filler used were unsaturated polyester resin and CaCO3, respectively. The mix proportions were determined to satisfy the requirement for the workability and slump according to aggregate sizes 5~10 mm. In the test results, regardless of kinds of aggregates and fiber contents, the void ratio, permeability coefficient and compressive strength of all types of PPC showed the higher than the criterion of porous concrete that is used in permeable pavement in Korea. Also, strengths of PPC with increase polypropylene fiber volume fraction showed slightly increased tendency due to increase binder with increase of fiber volume fraction. Accordingly, polypropylene fiber and recycled coarse aggregate can be used for permeable pavement.