• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.1-11
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• 2006

Attempts were made to analyze the national policy of soil contamination prevention and management of inactive or abandoned metal (IAM) mines in Korea. This approach focused on legal systems and legislation, remediation technology development, and the arrangement or distribution of budgets pertaining to national policy since the mid 1990's. Prevention of Mining Damage and Recovery Act enacted. Defines the roles, responsibility and budget of the government when recovering mine damages. However, in 2005 there still remains to improve the national policy of soil contamination prevention and management of IAM mines. Analysis of national and industrialized foreign countries including the United States, the United Kingdom, and the Netherlands suggest the following improvements: i) arranging distinct regulations between strict and non-strict liability criteria for potentially responsible parties; limiting innocent and non-strict liability depending on the period of incurred mining activity, ii) enhancing participation of local communities by enforcing law and legislation, iii) establishing a national database system of (potentially) IAM contaminated sites based on the Website-Geographic Information System, iv) carrying out site-specific risk assessments and remediation of IAM contaminated sites, v) preparation and distribution of clean-up fund at mine sites adequately, and vi) technology development for the cleaning of IAM contaminated sites; awarding positive incentives of a legal nature for participants applying newly developed technology in IAM mines.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.75-87
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• 2001

Inter-port competition is fiercer than in the past because of technological evolution in transport systems : the increasing side of containerships implies only a few calls in three or four ports at each end of the trade and the rest of the traffic being served by smaller feederships. It is therefore essential for big ports to be selected as one of these calls by the main shipowners, consortia and alliances to avoid rmarginalisation. In order to compete effectively, many ports have been obliged to modernise and extend considerably its existing ports or to build new port facilities. With the advent of major environmental legislation around the world, however, amenities such as fish and wildlife, clean air and water, access to the waterfront, and view protection took on greater importance. Ports are now being forced to incorporate environmental considerations into their planning and management functions in order to avoid additional costs or timing delays. The aim of this paper is to analyse the port value by which port comparison(or selection) will be made with HFP(Hierarchical Fuzzy Process) method. This was done by extracting and grouping the evaluation factors of port value by port experts : facility and location factor, logistics service factor environment and amenity factor, city and economic factor, and human and system factor. For empirical test of this method, 6 major ports in Northeast Asia were chosen and analysed. The order of importance for five evaluation factors were 1) facility and location factor 2) logistics service factor 3) human and system factor, 4) city and economic factor, and 5) environment and amenity factor. This means that geographical location and logistics services are still being considered as the most important factor to call the port by port users. even though environment and amenity factor shows relatively low figure. Among 6 major ports, Port of Kobe was ranked the first position in a comprehensive evaluation, while Ports of Busan and Kwangyang were 4th and 5th respectively. This implies that Port of Busan should make much efforts to enhance the existing facilities as well as management system.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.298-298
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• 2013

Finding renewable and clean energy resources is essential research to solve global warming and depletion of fossil fuels in modern society. Recently, complex harvesting of energy from multiple sources is available in our living environments using a single device has become highly desirable, representing a new trend in energy technologies. We report that when simultaneously driving the fusion and composite cells of two or more types, it is possible to make an affect the other cells to obtain a greater synergistic effect. To understand the coupling effect of photovoltaic and piezoelectric device, we fabricate the serially integrated hybrid cell (s-HC) based on organic solar cell (OSC) and piezoelectric nanogenerator (PNG). The size of increased voltage peaks when OSC and PNG are working on is larger than the case when only PNG is working. This voltage difference is the Voc change of OSC, not the voltage change of PNG and current density difference between these two cases is manifested more clearly. When the OSC and PNG are working in s-HC at the same time, piezoelectric potential (VPNG) is generated in ZnO and theoretical total voltage is sum of voltage of an OSC (VOSC) and VPNG. However, electrons from OSC are influenced by piezoelectric potential in ZnO and current loss of OSC in whole circuit decreases. As a result, VOSC increases temporarily. Current shows the similar behavior. PNG acts a resistance in the whole circuit and current loss occurs when the electrons from OSC pass through the PNG. But piezoelectric potential recover current loss and decrease the resistance of PNG. Our PNG can maintain piezoelectric potential when the strain is held owing to the LDH layer while general PNG cannot maintain piezoelectric potential. During the section that strain is held, voltage enhancement effect is maintained and same effect appeared even turn off the light. Actually at this time, electrons in ZnO nanosheets move to LDH and trapped by the positive charges in this layer. After this strain is held, piezoelectric potential of ZnO nanosheets is disappeared but potential difference which is developed by negative charge dominant LDH layer is remained. This potential acts similar role like piezoelectric potential in ZnO. Electrons from the OSC also are influenced by this potential and the more current flows.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.187-201
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• 1996

This study was to evaluate the efficiency of diffusive monitor using activated carbon fiber(ACF, KF-1500) in measuring airborne organic solvents. The following characteristics were identified and studied as critical to the performance of diffusive monitor; recovery, sampling rate, face velocity, reverse diffusion and storage stability. For the evaluation of the performance of this monitor, MIBK, PCE, toluene were used as organic solvents. In the sampling rate experiments, eight kinds of solvents (n-hexane, MEK, DIBK, MCF, TCE, CB, xylene, cumene) as well as the above solvents were used. The results were as follows: 1. The desorption efficiencies(DE's) of ACF diffusive monitor ranged from 83 % to 101 %. In contrast, those of coconut shell charcoal ranged from 78 % to 102 %. Especially, the DE's of ACF for the polar solvents such as MEK were superior to those of charcoal. 2. Experimental sampling rates on ACF were average 42ml/min(37-46ml/min) for 11 organic solvents at $24{\pm}2^{\circ}C$, $50{\pm}5%RH$. However ideal sampling rates(DA/L) were 33 % higher than experimental sampling rates. 3. The initial response(15~16 min) of the testing monitor was 2 times higher than the actual concentration determined by the reference methods at $24{\pm}2^{\circ}C$, $8{\pm}5%RH$ and $80{\pm}5%RH$. Within 1 hours, the curve reached a linear horizontal line at low humidity condition. But sampling efficiencies decreased with respect to time at high humidity condition. And sampling efficiencies were higher at high humidity condition than low humidity condition for MIBK. 4. At very low velocity (less than 0.02 m/sec), the concentration of ACF diffusive monitor were poorly estimated. But ACF diffusive monitor were not affected at higher velocity(0.2 m/sec-0.6 m/sec). 5. There was no significant reverse diffusion when the ACF monitors were exposed to clean air for 2 hours after being exposed for 2 hours at the level of 1 TLV. 6. There was no significant sample loss during 3 weeks of storage at room temperature and 5 weeks of storage at refrigeration.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.213-217
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• 2000

To investigate the cucumber regeneration from embryogenic calli, shoot tips of aseptically-grown cucumber seedlings were used as explants for establishing tissue cultures. Growth and differentiation of callus were studied by using Murashige and Skoog's (MS) medium containing 0.5 to 2 mg/L 2,4-D. Plantlets were induced from shoot tip culture on the plant growth regulators-free MS medium. Non-embryogenic calli and viscous calli were induced on the medium supplemented with 0.5 to 2 mg/L 2,4-D, but embryogenic callus was not induced on the same medium. Segments (ca. 5∼10 mm) of aseptically-grown hypocotyl from five to seven days old seedlings after germination were placed on MS medium supplemented with 1 mg/L 2,4-D for 50 days. Embryogenic calli and embryoids were induced only from the seedlings grown in dark condition, and hypocotyl was placed on the media explanted in light condition. Foully-five point one percent of white fragile calli and 0.6% yellowish compact calli formed roots. Yellowish callus lines were investigated to have a considerably higher concentration of crude proteins than white callus lines. Plantlets derived from embryogenic calli or embryoids have been transferred to pots containing sterile vermiculite and perlite. Normal fruits were harvested from nutrient culture on aggregated hydroponics in the F-clean house.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.45-52
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• 2008

The GTL(Gas to Liquids) technology, manufacturing synthesized oil from natural gas, had been developed about 1920 for the military purpose by Fischer and Tropsch, German scientists. And 1960, Sasol company had started commercializing the FT(Fischer-Tropsch) synthesis technology, for the transport fuel in South Africa. Until a recent date, the commercialization of GTL technology had been delayed by low oil price. But concern about depletion of petroleum resources, and development in synthesizing technology lead to spotlight on the GTL businesses. Especially, Qatar, which has rich natural gas fields, aims at utilizing natural gas like conventional oil resources. Therefore, around this nation, GTL plants construction has been promoted. There are mainly 3 processes to make GTL products(Diesel, Naphtha, lube oil, etc) from natural gas. The first is synthesis gas generation unit reforming hydrogen and carbomonoxide from natural gas. The second is FT synthesis unit converting synthesized gas to polymeric chain-hydrocarbon. The third is product upgrading unit making oil products from the FT synthesized oil. There are quite a little sulfur, nitrogen, and aromatic compounds in GTL products. GTL product has environmental premium in discharging less harmful particles than refinery oil products from crude to the human body. In short, the GTL is a clean technology, easier transportation mean, and has higher stability comparing to LNG works.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.98-104
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• 2006

The more the population grow, the severer the shortage of a basic human needs such as clean water, food, energy resources and so on. Recently, we aware that deep sea water can be utilized to solve comprehensively food, energy and water problems. In this study, inhibitory effect of the deep sea water of east coast (DSW) on platelet aggregation were investigated using washed platelet and beneficial effect of the change of lipid concentration on serum at various time intervals for three weeks. In this study six groups of 6-month-old Sparague-Dawley rats were examined. An intact group served as controls (C-1D : breeding for one day, C-1W : breeding for one week, C-3W : breeding for three week). The fourth group (1D-DSW) supplemented with DSW for one day. The fifth group (1W-DSW)supplemented with DSW for a week. The sixth group (3W-DSW)supplemented with DSW for three weeks. The total cholesterol and triglyceride concentration on serum of supplemented groups with the DSW for one or three weeks were significantly decreased. The serum HDL-cholesterol level in the DSW groups were significantly higher than the level in the control group. The supplementation of DSW for one day did not appear to have such a beneficial effect on lipid level. The ability of platelet aggregation of supplemented groups with DSW was less than control group. These results suggest that supplementation with DSW is positively influence on lipid concentration and platelet aggregation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.8
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• pp.711-719
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• 2017

Bladeless fan is becoming increasingly popular owing to its advantages, such as improved safety, easy to clean, and attractive shape. However, many people are reluctant to purchase it because of several disadvantages, such as noise and moderate wind; therefore, research on how improve wind generation without increasing the motor speed is required. This study investigates the optimization of the shape of the nozzle and nearby surface using CFD (Computational Fluid Dynamics) simulation, ANSYS fluent. The results are analyzed by ANOM (analysis of mean) and interaction analysis; therefore this study suggests the variables of affecting Coanda effect and satisfy the govern equation, the conservation of momentum. The optimal combination was found through a predictive equation. In this study, factors and levels that affect the mass flow rate were selected and experimental points were arranged using the orthogonal array table. The value of the mass flow rate was confirmed by ANSYS fluent, which is a CFD program. Through the ANOM, it was confirmed that the nozzle distance is the most influential parameter affecting the mass flow rate. Furthermore, the mass flow rate obtained from the predictive equation and the mass flow rate from the CFD correspond to the largest values. Results from this study confirmed that the mass flow rate is increased by a change in the shape, even if the motor speed did not increase.

• 한국해양학회지
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• v.7 no.1
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• pp.24-45
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• 1972

The Han River is an important water source in Seoul and neighbouring districts, for public and industrial supply, and for agriculture and fishery. Nowadays, more than six million inhabitants are supplied withe water from this river. The total length of the river is 470km, and has 17 10$\^$9/㎥ an average annual flow. The hydrographic characteristics at Seoul are 653㎥/sec in an average flow, 4,608㎥/sec in the maximum average flow, and 201㎥/sec in the minimum average flow. These are influenced in some degree by snowmelt in early spring, and greatly by the flood during summer. For the pollution problems, the periods of low flow are critical ones. As a rule they occur around the months November through June. Nowadays, most of the sewage from towns and industries is discharged untreated. Apart from domestic and industrial sewages, there are some discharges of mineral matter by mines in the upriver region. In general, water quality of the Han River is kept very clean and healthy until Kwangnaru of the upper region of Seoul. A large pollution, however, is received in the downstream by the domestic and industrial sewages of Seoul. It can be seen that dissolved oxygen, COD and BOD$\sub$5/ diminish markedly, and the intensity of almost every water parameter of the river continues to increase. Comparison of the figures for 1971 derived from a sampling point 40km downstream of Kwangnaru leads to the conclusion that hardness, Ca and Mg were no changed; alkalinity, Si and soluble- Fe were slightly increased; CO$\sub$2/, acidity, Cl, NO$\sub$2/-N, Cu, Zn and Al were increased in 2 and 3 times; total residue, total ignitious residue, COD, BOD$\sub$5/, NH$\sub$4/-N, PO$\sub$4/-P, Mn, Pb and total-Fe were increased in 4 to 7 times; and SO$\sub$4/, particulate-Fe and Cd were increased in 10 to 11 times. On the other hand, coliforms were increased in 650 times; fecal coliforms in 365 times; enterococci and total plate counts in 30 times, respectively. In view points of water quality standards, the down Han River water is now leveling out in Cd, coliforms and fecal coliforms for the agricultural use; in dissolved oxygen and some trace elements (Cu, Zn, Pb and Cd) for the fishery use; in ammonia, COD, BOD$\sub$5/, and Cd for the drinking use.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.4
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• pp.327-336
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• 2007

The 3D building modeling is one of crucial components in building 3D geospatial information. The existing methods for 3D building modeling depend mainly on manual photogrammetric processes by stereoplotter compiler, which indeed take great amount of time and efforts. In addition, some automatic methods that were proposed in research papers and experimental trials have limitations of describing the details of buildings with lack of geometric accuracy. It is essential in automatic fashion that the boundary and shape of buildings should be drawn effortlessly by a sophisticated algorithm. In recent years, airborne LiDAR data representing earth surface in 3D has been utilized in many different fields. However, it is still in technical difficulties for clean and correct boundary extraction without human intervention. The usage of airborne LiDAR data will be much feasible to reconstruct the roof tops of buildings whose boundary lines could be taken out from existing digital maps. The paper proposed a method to reconstruct the roof tops of buildings using airborne LiDAR data with building boundary lines from digital map. The primary process is to perform octree-based segmentation to airborne LiDAR data recursively in 3D space till there are no more airborne LiDAR points to be segmented. Once the octree-based segmentation has been completed, each segmented patch is thereafter merged based on geometric spatial characteristics. The experimental results showed that the proposed method were capable of extracting various building roof components such as plane, gable, polyhedric and curved surface.