• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.2
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• pp.118-127
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• 2009

This study tries to develop model in order to assess personal factors of senior traffic accidents that are widely recognized as one of the social problems. For the current practice. it gathers data (Simulation & Questionnaire Survey) of KOTSA and conducts Poisson and Negative Binomial Regression Analysis to develop traffic accident severity model. The results show that elderly drivers' accidents are mainly affected by attentiveness selection, velocity prediction ability and attentiveness distribution ability in a positive(+) way. Second, non-senior drivers' accidents are also positively(+) influenced by attentiveness selection, velocity prediction, distance perception, attentiveness distribution ability and attentiveness diversion ability. Therefore, influencing factors of senior and non-senior drivers to vehicle accidents are different. This eventually poses a indication that preliminary education for car accident prevention should be implemented based up[n the distinction between senior drivers and non-senior drivers.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1734-1737
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• 2015

Insulating characteristics of Cl₂-He mixture gases in gas discharges were analysed to evaluate ability of these gases for using in medium voltage and many industries. These are electron transport coefficients, which are the electron drift velocity, density-normalized longitudinal diffusion coefficient, and density-normalized effective ionization coefficient, in Cl₂-He mixtures. A two-term approximation of the Boltzmann equation was used to calculate the electron transport coefficients for the first time over a wide range of E/N (ratio of the electric field E to the neutral number density N). The limiting field strength values of E/N, (E/N)_lim, for these binary gas mixtures were also derived and compared with those of the pure SF₆ gas.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.1
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• pp.37-44
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• 1998

In this study a new hybrid method is developed for solving flow-dominated transport problems accurately and effectively. The method takes the forward-tracking particle method for advection. However, differently from the random-walk Lagrangian approach it solves the diffusion process on the fixed Eulerian grids. Therefore, neither any interpolating algorithm nor a large enough number of particles is required. The method was successfully examined for both cases of instantaneous and continuous sources released at a point. Comparison with a surrounding 5-point Hermite polynomial method (Eulerian-Lagrangian method) and the random-walk pure Lagrangian method shows that the present method is superior in result accuracy and time-saving ability.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.769-779
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• 2023

This paper describes an hp-angular adaptivity algorithm in the discrete ordinates method for Boltzmann transport applications with strong angular effects. This adaptivity uses discontinuous finite element quadrature sets with different degrees, which updates both angular mesh and the degree of the underlying discontinuous finite element basis functions, allowing different angular local refinement to be applied in space. The regular and goal-based error metrics are considered in this algorithm to locate some regions to be refined. A mapping algorithm derived by moment conservation is developed to pass the angular solution between spatial regions with different quadrature sets. The proposed method is applied to some test problems that demonstrate the ability of this hp-angular adaptivity to resolve complex fluxes with relatively few angular unknowns. Results illustrate that a reduction to approximately 1/50 in quadrature ordinates for a given accuracy compared with uniform angular discretization. This method therefore offers a highly efficient angular adaptivity for investigating difficult particle transport problems.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.675-679
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• 2004

The existing conjugated blue emitting material polymer which has been used for the two-wavelength method white-emission has good stability and low operating voltage as merits, but the imbalanced carrier transport has been indicated as problem area. We have introduced a novel blue emitting material having perylene moiety unit with hole transporting ability and blue emitting property and triazine moiety unit with electron transporting ability into the same host chain. We have synthesized N-[p-(perylen-3-y1)pheny1]methacry1 amide (PPMA) monomer and [N-(2,4-dipheny1-1,3,5-triazine)pheny1 methacry1 amide] (DTPM) monomer having blue light-emitting unit and electron transport unit, respectively by three steps. A novel non-conjugated blue emitting material Poly[N -[p­(perylene-3-y1) pheny1] methacry1 amide-co-N-[P-(4,6-dipheny1-1,3,5-triazine-2-y1]pheny1]methacry1 amide] (PPPMA-co-DTPM) copolymer having electron transporting unit was synthesized by the solution polymerization of PPMA and DTPM monomers with an AIBN initiator and showed high yield of $75{\%}$. It was very soluble in common organic solvents, and the fabrication of the thin film using a spin coating method was very simple. The PPPMA exhibited a good thermal stability.

• Journal of Sasang Constitutional Medicine
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• v.9 no.2
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• pp.187-201
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• 1997

An experimental study was done to examine the effects of Dokwhaljiwhang-tang on gastro-intestinal track and central nervous system and were undertaken by being carried out with rat. The following results have been obtained ; 1. Dokwhaljiwhang-tang showed to have an inhibitory effect on the smooth muscle contraction of the isolated ileum by acetylcholene chloride and barium chloride. 2. Dokwhaljiwhang-tang showed to have an inhibitory effect on the contraction of the gastric fundus-strip by acetylcholine chloride and barium chloride. 3. The preventive effect was recognized on the pylorus-ligated ulcer, by administration of Dokwhaljiwhang-tang. 4. The preventive effect was not recognized on the indomethacine -induced ulcer, by administration of Dokwhaljiwhang-tang. 5. The inhibitory effects on the secretion gastric juice, free acidity were recognized, by administration of Dokwhaljiwhang-tang 6. The transport ability in the small intestine was increased, by administration of Dokwhaljiwhang-tang. 7. The transport ability in the large intestine was increased, by administration of Dokwhaljiwhang-tang. 8. The analgesic effect was recognized, by administration of Dokwhaljiwhang-tang. 9. The effect of sleeping time was not recognized, by administration of Dokwhaljiwhang-tang. according to the results, it is considered that Dokwhaljiwhang-tang has effects of gastric ulcer, chronic gastritis,hyper-acidity, gastroptosis such as abdominal discomfort, gastric acid, indigestion and anorexia.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.3 s.11
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• pp.24-28
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• 2006

This paper proposed design and implementation of automation system that recognize device module boards automatically that are connected on main control board. The system of this paper is divided to main board and device module boards, and the main board is designed a board by slot structure. The slot structure is possible a extension for upgrade and addition of board ability. Besides, it is easier a establishment and disjointing because it recognizes automatically a device board. The proposed system in this paper compares with K10S1 PLC. The result shows an advantage of extensibility and ability, and it is reduced expense and period for development.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.19-24
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• 2004

The objective of this study was to develop a mechanistically based mathematical model that would consider the interdependence of VOCs transport, microbial activity, and sorptive interactions in a moist, unsaturated soil. Because the focus of the model was on description of natural attenuation, the advective VOCs transport that is induced in engineered remediation processes such as vapor extraction was not considered. The utility of the model was assessed through its ability to describe experimental observations from diffusion experiments using toluene as a representative VOCs in well-defined soil columns that contained a toluene degrading bacterium, Pseudomonas putida G7 md Fl, as the sole active microbial species. The gas-liquid mass-transfer was found to be a key parameter controlling the ability of bacteria to degrade VOCs. This finding indicates that soil size and geometry are likely to be important parameters in assessing the possible success of natural attenuation of VOCs in contaminated unsaturated soils. Therefore we found that Pseudomonas putida G7 and Fl were very effective to remove of refractory pollutants such as toluene in soil by Bio-filter

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.82-96
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• 1997

In order to investigate the effect of Daewhajungeum on the isolated organs, gastrointestinal tract and C.N.S., some kinds of experiments using mice and rats were done. The results were as follows; 1. Daewhajungeum showed the inhibitory effect on the smooth muscle contraction of the isolated ileum and colon induced by acethylchorine chloride and barium chloride in mice. 2. Daewhajungeum showed inhibitory effect on the contraction of the fundus-strip induced by acethylchorine chloride and barium chloride in rats. 3. The preventive effect on pyloric ulcer, indomethacin induced ulcer and ethanol-HCl induced ulcer of mice was recognized. 4. The effect on the acidity of gastric juice was suppressed, but the effect on the pepsin output was not recognized. 5. The transport ability of small and large intestine was significantly decressed. 6. The analgesic effect and the sedative effect were recognized so that the effect of the C.N.S was suggested.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.2
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• pp.86-94
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• 2023

Tonnage taxation has contributed to developing the Korean maritime industry through tax relief for shipping companies. The current tonnage taxation relies on the net tonnage as an earning-capacity indicator in a merchant ship. Although the tonnage tax accords with horizontal equity, it does not match vertical equity because of the different taxable capacities of an individual company. Nowadays, maritime transport uses a dedicated vessel, and each shipping freight embeds a different value of time. It means the tonnage taxation regime should consider the added value of each shipping freight. Meanwhile, as the environmental regulations led by the International Maritime Organization are being strengthened, the Korean merchant fleet must be eco-friendly soon after. This study explores the alternative to renewing tonnage taxation by utilizing the Greenship certification and considering the ability-to-pay principle. Because the Greenship certification scheme encourages shipping decarbonization, maritime transport by a certified ocean-going vessel comes to be treated as an activity for the green economy. Special taxation for the green economy may contribute to shipping sustainability and market competitiveness.