• Journal of Korean Society of Transportation
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• v.27 no.1
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• pp.117-127
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• 2009

This study analyzed the uncertainty of the forecasted link traffic flow, and estimated of the interval link flow using Korea Transport Data Base (KTDB) to consider those risks into the feasibility study. In the paper, the uncertainty was analyzed according to the stochastic variation of the KTDB origin-destination traffic. It was found that the uncertainty of the entire network traffic forecasts was 15.4% in average,. when the stochastic variation of the KTDB was considered. The results showed that the more congested the roads were, the bigger the uncertainty of forecasted link traffic flow were found. In particular, we estimated the variance of the forecasted traffic flow, and suggested interval estimates of the forecasted traffic flow instead of point estimates which were presented in the common feasibility studies. These results are expected to contribute the quantitative evaluation of uncertain road investment projects and to provide valuable information to the decision makers for the transport investment.

• Nuclear Engineering and Technology
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• v.24 no.1
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• pp.1-13
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• 1992

A one-group cross section data base of the ORIGEN2 computer code was developed for research reactor applications. For this, ENDF/B-IV and -V data were processed using the NJOY code system into 69-group data. The burnup-dependent weighting spectra for KMRR were calculated with the WIMS-KAERI computer code, and then the 69-group data were collapsed to one-group using the spectra. The ORIGEN2-predicted burnup-dependent acti-nide compositions of KMRR spent fuel using the newly developed data base show a good agreement with the results of detailed multigroup transport calculation. In addition, the burnup characteristics of KMRR spent fuel was analyzed with the new data base.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.2
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• pp.277-286
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• 2013

Cross-shore sediment transport is very important factor in the design of coastal structures, and the beach profile is mainly affected by a number of parameters, such as wave height and period, beach slope, and the material properties of the bed. In this study cross-shore sediment movement was investigated using a physical model and various offshore bar geometric parameters were determined by the resultant erosion profile. The experiments on cross- shore sediment transport carried out in a laboratory wave channel for initial base slopes of 1/8, 1/10 and 1/15. Using the regular waves with different deep-water wave steepness generated by a pedal-type wave generator, the geometrical of sediment transport rate and considerable characteristics of beach profiles under storm conditions and bar parameters affecting on-off shore sediment transport are investigated for the beach materials with the medium diameter of $d_{50}$=0.25, 0.32, 0.45, 0.62 and 0.80 mm. Non-dimensional equations were obtained by using linear and non-linear regression methods through the experimental data and were compared with previously developed equations in the literature. The results have shown that the experimental data fitted well to the proposed equations with respect to the previously developed equations.

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.262-268
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• 2008

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.4
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• pp.260-280
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• 1994

The STEM II(Sulfur Transport Eulerian Model II) was adapted to simulate transport/ chemistry/deposition of air Pollutants in the Eastern China and Korea. A 32 hour model simulation starting from 9 A.M. of 1989 November 25 during which no preciptation was observed. The Prevailing wind direction is from west to east. The MM4(Meteorological Model Version 4) was used to generate meteorological data such as temperatures, horizontal wind velocities and directions, humidities, air densities. Eddy diffusivities, dry deposition velocities and vertical wind velocities were calculated from the meteorological data. The initial condition and the emission data base were constructed from the measurements and governmental reports respectively. The model predictions of NO, NO$_2$, SO$_2$, $O_3$ at Seoul, Inchon and Pusan agree reasonably well with measurements. The model's predictability for the primary air pollutants is improved considerably as the time passes. Thus, it is concluded that the model's predictability can be significantly enhanced by reducing the uncertainties of initial conditions.

• KDI Journal of Economic Policy
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• v.40 no.2
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• pp.23-52
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• 2018

Given the limited availability of data in South Korea, this study proposes a method by which to estimate regional capital stock by modifying the benchmark year method (BYM) and applies it to estimate regional net capital stock by sector in transport infrastructure. First, it estimates time-varying sectoral depreciation rates using the sectoral net capital stock and the investment amount for each period. Second, it estimates the net capital stock of each period using the net capital stock in the base year and the investment in each period. Third, in order to ensure that the sum of net capital stocks by region is equal to the nationwide estimate, the national estimates are allocated to each region according to the proportion of the values derived from the previous stage. The proposed method can alleviate well-known problems associated with conventional BYMs, specifically the upward bias and arbitrary choice of the depreciation rate.

• Journal of Radiation Protection and Research
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• v.29 no.2
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• pp.117-127
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• 2004

A dynamic compartment model was developed to evaluate the transport of accidently released radionuclides onto rice-fields. In the model, the surface water compartment and shoot-base absorption were introduced to account for the effect of irrigation, which is essential to a rice cultivation. The soil mixing by plough and irrigation before transplanting rice was also considered, and the rate of root-uptake and shoot-base absorption were modeled in terms of the function of biomass. In order to test the validation of the model, it was applied to the analysis of some simulated $^{137}Cs$ deposition experiments that were performed while cultivating rice in a greenhouse using soils sampled from rice-fields around Kori, Yonggwang and Ulchin nuclear power plants. The model prediction was generally agreed within about one order of magnitude with experimental data.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.1
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• pp.103-110
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• 2013

WAVE system is a vehicle communication technology. The system provides the services to prevent vehicle accidents that might occur during driving. Also, it is used to provide various services such as monitoring vehicle management and system failure. In this paper, we divide module that manages WAVE MAC state into a WSMP base MLME module and IP base module and we design and implement a parameter environment between WME module to manage the state of the WAVE system and MLMEX module to mange IP base of WAVE MAC therefore the date to be processed.Also, in order to verify the validity, we have carried out experiments to compare the speed of data processing by dividing data of 5Mbyte, 10Mbyte, 20Mbyte into the packets of 2KByte and 4KByte. Therefore, in WAVE system, the Parameter environments and data processing speed between WME and MLMEX module can be utilized in the various service of vehicle communication technology depending on the speed of data processing.

• The Korean Journal of Community Living Science
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• v.27 no.2
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• pp.295-304
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• 2016

This study was conducted to evaluate and compare the waterproofness and water vapor transport properties of 30 waterproof and breathable textiles in the market. MVTR upright cup test with water, MVTR inverted cup test with potassium acetate, and sweating hot plate test method were used for measuring the breathability of fabric samples. The waterproofness of all fabric samples and evaporative resistance of garment ensembles made with 5 selected waterproof and breathable textiles out of 30 samples were tested. The results of this study were as follows. The base fabrics of the most samples were basic weave structure with either polyester or nylon fiber. The waterproofness was over $5000mmH_2O$ for all the samples except densely woven fabrics. The evaporative resistance of garments that were made out of 5 fabric samples with a range of low to high breathability ranged $39.9{\sim}56.7m^2{\cdot}P{\cdot}W^{-1}$. The data of the water vapor transport properties of fabric samples varied with different test methods. Overall the bicomponent film fabrics showed better breathability and less standard deviation regardless of test methods. It is expected the breathability data without the information of test conditions used for marketing would confuse the consumers and the apparel manufacturers.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.1
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• pp.79-86
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• 2013

In this paper which it is relating to the DSRC system based road side equipment, we propose the protocol stack architecture of road side equipment and the process structure of the main RM, L7 and LLC layers which is road side equipment device as well. And also we design the signal flow and data-transfer process as well between road side equipment and on board equipment to describe the installation process between road side equipment and von board equipment based on DSRC system. Thus, it is possible to provide various application services between intelligent transportation systems of road side equipment and local server, as well as it enables the local server managing the memorys of on board equipment which entry in service area thru the road side equipment.