• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1350-1364
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• 2023

2D/1D coupling method is an important neutron transport calculation method due to its high accuracy and relatively low computation cost. However, 2D/1D coupling method may diverge especially in small axial mesh size. To analyze the convergence behavior of 2D/1D coupling method, a Fourier analysis for k-eigenvalue neutron transport problems is implemented. The analysis results present the divergence problem of 2D/1D coupling method in small axial mesh size. Several common attempts are made to solve the divergence problem, which are to increase the number of inner iterations of the 2D or 1D calculation, and two times 1D calculations per outer iteration. However, these attempts only could improve the convergence rate but cannot deal with the divergence problem of 2D/1D coupling method thoroughly. Moreover, the choice of axial solvers, such as DGFEM SN and traditional SN, and its effect on the convergence behavior are also discussed. The results show that the choice of axial solver is a key point for the convergence of 2D/1D method. The DGFEM SN based 2D/1D method could converge within a wide range of optical thickness region, which is superior to that of traditional SN method.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.67-77
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• 2010

Growth of oil and chemical industries has been remarkable during recent years. Hazardous materials (Hazmat) make frequent use in the wide range of industries. It increases the frequency of Hazmat transport and it leads to increase the number of accidents. Optimal Hazmat routes can reduce damage. Thus, the objective of this study is to minimize the areas impacted by Hazmat accidents by adopting experts' opinion in planning the route. We calculated weights using AHP (Analytic Hierarchy Process) and deduced the best route by applying this weights. Results showed that in the case of shortest route versus weighted route, the percentage of population damage has been decreased by 33.4% in the comparison between shortest route and optimally weighted route. And the percentage of environmental damage also has been decreased by 21.8%. Social damage has been decreased by 1521.7%. In the case of none weighted route versus weighted route, the percentage of population damage has been decreased by 2.6% when we adopted weighted route. Consequently, the recommended route with weighted risk assessment avoids densely populated area comparing with none weighted route. Further research needs to be carried out in order to figure out the specific cost-effectiveness analysis applying the equal cost unit for each factor.

• Journal of Advanced Navigation Technology
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• v.15 no.5
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• pp.893-905
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• 2011

CUPPS is the latest international standard passenger processing system which is operated with airlines' check-in system, DCS (Departure Control System) in order to provide check-in and boarding services to passengers. The CUPPS standard has been revised in August 2009 leading by IATA (International Air Transport Association) who recommends replacing old legacy common use system with CUPPS to airports and airlines around the world. IATA is expecting to reduce the installation and maintenance cost of CUPPS by standardizing various legacy common use systems and device controls. Airlines are also expecting to take advantage of the system to reduce the application development cost as developing only one standard CUPPS application instead of developing multiple applications for nonstandard legacy systems. This research which focuses on development completed AIRCUS, R&D project of ministry of land, transport and maritime affairs accomplished by IIA, will present the result of pilot trial and the effective approach methods to increase the possibility of expanding overseas business by comparing old legacy system with CUPPS to prove the dominance of CUPPS over the legacy systems as well as doing foreign case studies.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.11-17
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• 2015

The increase of international and domestic trade according to global industrialization and economic growth has raised the national logistic cost in connection with physical distribution of articles. In order to reduce these costs and rise up national industrial competitiveness, Korea has also tried to improve the efficiency of logistics with various methods as advanced countries did. Especially, Korea government has decided standard dimension of pallets with T11 ($1100{\times}1100mm$) on the basis of unit load system in early 2000s, and certification program for logistics equipments has been operated to keep up the compatibility for the equipments and packaging with modulation of T11. Consequently, this certification program has contributed to extend standardization for logistics and to grow up 3 party logistics, but compared with advanced countries, the rate of national logistics cost to GDP (gross domestic product) still shows about 3% gap as demands for certification have been decreased in the recent. In this study, therefore, we proposed the development of logistics certification system based on social needs as a policy device to activate logistic industry as well as improve the efficiency of national logistics after we had analyzed all of certification programs for logistics being run in Korea. Namely, the first is the development of certification project for Northeast Asia's logistics corresponding to necessity for applying returnable transport system according to increasing the amount of trade between Northeast Asia's countries. The second is the development of certification project for safe transportation of packaging corresponding to costumer's needs for safe transit according to the growth of electronic commerce and the increase of global distribution.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.619-626
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• 2007

It is of special interest in our membrane separation technology due to its low energy consumption and cost, relatively simple equipment, low investment and operation cost, et al. Full scale utilization of such processes can be widely utilized to the various fields. Using the difference of permeability of gas molecules between the filter layers, it is able to separate effectually pure gases from the mixed gases. In this paper, the membranes of PDMS, ${\gamma}-radiated$ PDMS, PTFE, PTFE-X are chosen to develop the predictive model for the separation of pure gases such as oxygen, nitrogen, hydrogen, and other gases from mixed gases. By utilizing the thermodynamic gas properties($\sigma$, $\varepsilon/k$) and experimental data of gas transport characteristics for different polymer membranes, it is able to develop the predictive model equation under the influence of temperature, pressure and polymer characteristics. Predictive model developed in this research showed good agreement with experimental data of gas permeability characteristics for develop four different polymer membranes. The proposed model can also be extended to the general equation for predicting the separation of gases based on the properties of polymeric membranes.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.330-336
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• 2012

We surveyed and evaluated quantities and distribution characteristics of debris on the sea floor around active fishing grounds around the islands in the southwest coast of Korea in 2007 where the average depth is below 40m. Proper recovery gears mainly to haul the derelict fishing gears are selected considering the sea bed types of the areas. The collected debris amounts were used to estimate the total amount of the surveyed area. The number of hauls per trial times the amount of the debris was extended to whole sampling area and the weighting factor from the opinion was applied to reach the total amount of marine debris on the floor. The amount of the deposited marine debris around Wangdeung-do area is estimated as about 686 $kg/km^2$, and the cost of the collection and treatment for the deposited marine debris is estimated about 3.9 billion KRW after consideration of the proper size of the working ships, labor, transport and treatment cost.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.127-136
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• 2011

The typical unit infrastructure cost estimation techniques adopted so far in implementing the Korean Impact Fee Zoning have rather been centered around the unilateral simple cost models. The techniques, as such, have frequently been criticized for their lack of flexibility in properly reflecting the regional differences as well as the peculiarities of individual development projects. The Ministry of Land, Transport, and Maritime Affairs (MLTM), in this regard, has recently introduced an enhanced alternative technique. Using the NGIS data, the study probes the viability of the MLTM's new technique by testing the entire estimation process based on the case area in Ansung City. Reflecting the City's characteristics, the study assumes a composite land use plan that accommodates the industrial area in addition to typical residential areas. As an extensive empirical case study, the research has found from the new technique considerable technical merits to overcome the existing shortcomings and summarized its significant policy implications.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1395-1411
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• 2009

The Korea railroad industry has experienced the operating deficit annually since 1980. And the ridership has been reduced since 1990. Therefore, a structural reform of the Korea railroad industry conducted at 2003. Basic principles of their structural reform are no differences among the Korea and advanced counties. But different outcomes depending on each country situation appears. These cost functions appear the existence of all economic of scale. And when increase the average transport distance annually, the average cost reduce annually. The results of structural reform by comparing before and after, the average cost was lower than previously. The Structural reform and the operation of the KTX, the two effects at the same time, the synergy effect has occurred. Because of the synergy effect, the performance is estimated to be larger. Due to the effective operation of structural reform that could reduce costs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.4
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• pp.231-237
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• 2018

In this study, two important requirements for the home production of a robot to detect and remove improvised explosive devices (IEDs) are presented in terms of the total cost for robot system development and the performance improvement of the mine detection technology. Firstly, cost analyses were performed in order to provide a reasonable solution following an engineering estimate method. As a result, the total cost for a mass production system without the mine detection system was estimated to be approximately 396 million won. For the case including the mine detection system, the total cost was estimated to be approximately 411 million won, in which labor costs and overhead charges were slightly increased and the material costs for the mine detection system were negligible. Secondly, a method for fabricating the carbon nanotube (CNT) based gas detection sensor was studied. The detection electrodes were formed by a photolithography process using a photosensitive CNT paste. As a result, this method was shown to be a scalable and expandable technology for producing excellent mine detection sensors. In particular, it was found that surface treatments by using adhesive taping or ion beam bombardment methods are effective for exposing the CNTs to the ambient air environment. Fowler-Nordheim (F-N) plots were obtained from the electron-emission characteristics of the surface treated CNT paste. The F-N plot suggests that sufficient electrons are available for transport between CNT surfaces and chemical molecules, which will make an effective chemiresistive sensor for the advanced IED detection system.

• Journal of Korean Society of Transportation
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• v.17 no.4
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• pp.99-110
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• 1999

With a growing awareness, transportation is the maior source of urban air pollution. Planners and policy-makers are strongly urged to care the impacts of transportation management strategies on environment. Since transport-related air Pollution can be regarded as negative externalities of transport, it is indispensable to evaluate chanties in air quality which seems to occur when proposed transport measures are implemented. In addition, transport measures should be integrated in a set of combined Paradigm regarding transport and environment. Based on the integrated Paradigm between transportation demand management(TDM) and environmental planning, the main focus is given to apply environment cost internalizing measures to the short-term congestion management Program(SCMP) in Seoul, that has been developed in 1998 by Seoul Development Institute. Three modules are analyzed: without and/or with ￦500, ￦1000 emission plus gas tax, respectively. From the empirical applications on Seoul city, one of the most exemplary findings in SCMP program is that, emission plus gas tax can be a very useful measure to reduce vehicular emissions by targeting major Pollutants differently, rather than by dealing with pollutants collectively. Further research that provides (1)showing the spatial variation of pollution levels along the intersections, (2)more developing combined Paradigm between transport, land use, and environment, (3)using environmental road capacity rather than Physical-aspects of road capacity, and (4)continuing R&D on air quality constrained TDM, can contribute significantly to applications of the real and efficient environment-constrained transportation planning.