• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.33-44
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• 2013

Personal Rapid Transit(PRT) has emerged as a promising transportation mode for transit-oriented sustainable communities. In this study, an alternative design of questionnaire survey is proposed in order to capture traveler's perception of an unexperienced transportation mode. This study aims at predicting the mode choice diversion behavior of potential PRT users who do not have experience of using it previously, considering their willingness-to-pay. The proposed model was applied to predict an aggregate forecast of PRT patronage for the city of Songdo where PRT is considered to be constructed. For validation of the proposed model, the price elasticity of PRT demand was analyzed, compared with existing models. The analysis results suggest that the proposed design of questionnaire survey is able to capture respondents' attitude and perception to unexperienced transportation mode in an effective manner. Also, they show that the proposed diversion rate model is more realistic than existing models in explaining the effects of users' willingness-to-pay for predicting PRT patronage.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.81-92
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• 2012

The current Korean preliminary feasibility study guidebook provides a simple method for determining the impact area of a transportation project without taking its characteristics into account, which often leads travelers to switch their travel modes. Hence, this study develops a comprehensive methodology for defining the impact area when evaluating railroad projects, which can significantly affect travel mode choice behaviors. To develop the methodology, a hypothetical project was devised. The analysis results show that the convergence of mode-diverted trip rates is improved from 76% to 93% by implementing the proposed method. In addition, there was a significant difference in benefits (about 10.9 billion won) between adopting the current method and the proposed method.

• Geomechanics and Engineering
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• v.35 no.1
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• pp.13-27
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• 2023

The model production for large-scale (lateral length ≥ 2.0 m) capillary barrier (CB) model tests is time and cost-intensive. To address these limitations, the framework of a small-scale CB (SSCB) model test under the lateral no-flow condition has been established. In this study, to validate the experimental methodology of the SSCB model test, a series of seepage analyses on the SSCB model test and engineered slopes in the same and additional test conditions was performed. First, the seepage behavior and diversion length (L_D) of the CB system were investigated under three rainfall conditions. In the seepage analysis for the engineered slopes with different slope angles and sand layer thicknesses, the L_D increased with the increase in the slope angle and sand layer thickness, although the increase rate of the L_D with the sand layer thickness exhibited an upper limit. The L_D values from the seepage analysis agreed well with the results estimated from the laboratory SSCB mode test. Therefore, it can be concluded that the experimental methodology of the SSCB model test is one of the promising alternatives to efficiently evaluate the water-shielding performance of the CB system for an engineered slope.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.2
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• pp.123-136
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• 2015

The present study numerically investigates the effect of shield on the flow characteristics of Hartmann whistle. The flow characteristics of un-shielded Hartmann whistle are compared with whistles of different shield heights 15 mm, 17 mm, 20 mm, 25 mm and 30 mm. The comparison of Mach number contours and transient velocity vectors of shielded Hartmann whistles with un-shielded ones for the same conditions reveal that the presence of shield causes the exiting jet to stick to the wall of the shield without causing spill-over around the cavity inlet, thus sustaining the shock oscillation as seen in the unshielded Hartmann whistle, which has intense flow/shock oscillation and spill-over around the cavity mouth. The velocity vectors indicate jet regurgitance in shielded whistles showing inflow and outflow phases like un-shielded ones with different regurgitant phases. The sinusoidal variation of mass flow rate at the cavity inlet in un-shielded Hartmann whistle indicates jet regurgitance as the primary operating mode with large flow diversion around the cavity mouth whereas the non-sinusoidal behavior in shielded ones represent that the jet regurgitance is not the dominant operating mode. Thus, this paper sufficiently demonstrates the effect of shield in modifying the flow/shock oscillations in the vicinity of the cavity mouth.

• East Asian Economic Review
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• v.18 no.4
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• pp.425-461
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• 2014

This paper analyzes the impact of the Canada-Korea Free Trade Agreement on the basis of the published text and agreed schedule of commitments. We find that the Agreement reinforces existing patterns of comparative advantage between Canada (agriculture and resource-based sectors) and Korea (autos and other industries). The sensitive sectors that held up the deal for years - autos into Canada and beef into Korea - witness major trade gains, but are not unduly disrupted. In both economies, the major output gains otherwise come in non-traded services sectors, driven by income effects. We find that trade diversion effects are quite significant; this lends support for the domino theory of major free trade agreements - since the Korea-EU agreement broke the ice, the pressure has intensified on third parties to re-level playing fields by striking their own deals. The study breaks new ground in modelling services trade by developing policy impacts based on the extent to which the text of the Agreement modifies Korea's and Canada's scores on the OECD's Services Trade Restrictiveness Index and by providing estimates of Mode 3 Services trade impacts. The analysis of the Agreement as negotiated, the present study, in our view, is a step forward in understanding the impact of modern free trade agreements.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.131-140
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• 2009

A diversity of railway network function enhancement projects such as the double tracking, electrification, and direct operation have been actively executed to improve the railway service. When the new rapid railway is provided, how many people will use it instead of other transports? How will the railway choice behavior be changed? Accordingly, in this paper, the applicability of diverted travel demand forecast method by Stated Preference(SP) and Transfer Price(TP) data was reviewed for Daegu metropolitan railway service. As the result of implementing the Revealed Preference(RP) and RP+SP model, the total travel time and travel cost parameters are of the right sign and are highly significant. In particular, when TP data is used as the complementary investigation of SP, the boundary value of diverted travel demand can be easily identified by railway fare and travel time service level. Therefore, it is considered that this will practically apply even in other regions as well as Daegu metropolitan railway.

• Land and Housing Review
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• v.3 no.1
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• pp.33-43
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• 2012

The research which it sees is the simulation research for "The Ecological Diversion of Forest Land-Use System". It accomplished the simulation which applies a permission standard, it developed escape it did a model and the basic draft. From the research which it sees in order to investigate the application characteristic of natural intimate mountain district application standard the mountain district whole aspect instance middle actual object a time mountain district use standard about under selecting which it will yell it applied. "Natural intimate mountain district development standard triangular position plan research" from compatibility of the mode of life mountain district whole aspect permission standard which is proposed about under investigating it presented the improvement program and a institutional improvement direction of corresponding standard. About under preserving plan it applies the yearly environment the mountain district to sleep it prepares the foundation for it accomplished the transcendental research for. With the achievement resources which the mountain district has resultantly must preserve a value, limit of the development size it will be able to minimize the effect which it follows in development, the arrangement method back could be proposed, also the case which will use the mountain district where it is damaged induces the development which cabinets to the concept of demobilization, the case which will apply the existing forest resources takes a triangular position with the act it will be able to increase the circulating value of the resources and will do.

• Nuclear Engineering and Technology
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• v.52 no.6
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• pp.1252-1258
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• 2020

This study explores the ability of non-destructive assay techniques to detect a partial material defect in which 100 g of plutonium are diverted from the center of a 1000 g can of PuO₂ powder. Four safeguards measurements techniques: neutron multiplicity counting, calorimetry, gravimetry, and gamma ray spectroscopy are used in an attempt to detect the defect. Several materials are added to the partial defect PuO₂ can to replicate signatures of the diverted material. ²⁵²Cf is used to compensate for the doubles neutron counts, ²⁴¹Am is used to compensate for the decay heat, and aluminum is used to compensate for the weight. Although, the doubles and triples difference before and after diversion are statistically indistinguishable with the AWCC in fast and thermal mode, the difference in the singles counts are statistically detectable in both modes. The relatively short half-life of ²⁵²Cf leads to a decrease (three sigma uncertainty) in the doubles neutron counts after 161 days. Combining this with the precise quantity of ²⁴¹Am needed (10.7 g) to mimic the heat signature and the extreme precision in ²⁵²Cf mass needed to defeat neutron multiplicity measurements gives reassurance in the International Atomic Energy Agency's ability to detect partial material defects.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.2
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• pp.23-32
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• 1993

This paper describes the background and the development of a hydrologic network flow model. The model was development to simulate daily water demand and supply for selected stream reaches within a watershed, and used as a tool for evaluating, simulating, and planning a water resources system. The proposed network flow model considers daily runoff from subareas, various water demands, and diversion structures within each subarea. Daily streamflow at a reach is simulated after balancing the water demands from subareas. The lateral inflow from subareas is simulated using a modified tank model. Total water demands consist of the daily demands for agricultural, domestic, industrial, livestock, fishery, and environmental uses within a rural district. The return flow, diversions from sources and storage components such as reservoirs were also incorporated into the mode l . The developed model is a generalized version that may be applied to different combinations of river reaches for a given system. This may help potential users identify areas where water supply does not suffice the demands for different time horizons.

• Journal of Distribution Science
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• v.14 no.4
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• pp.33-38
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• 2016

Purpose - This study purposes to analyze the impact of regional economic integration and macroeconomic on Indonesian FDI inflows. Research design, data, and methodology - Data were collected from bilateral relation between Indonesia and 21 home countries whose dominant share FDI to Indonesia from 2005 to 2013. Analysis method was conducted by panel gravity modeI to find the impact of regional economic integration and macroeconomic on Indonesian FDI inflows. Results - The empirical results show that GDP of the home country and Indonesia have a positive impact on Indonesia FDI. Distance and home country real interest rate have a negative impact on Indonesia FDI. Economic integration of European Union (EU) and Indonesia's cooperation with Japan in ASEAN-Japan Comprehensive Economic Partnership (AJCEP) have created impact of investment creation on Indonesia FDI, unfortunately, economic integration of ASEAN has created impact of investment diversion on Indonesian FDI. Conclusions - In order to increase FDI inflow to Indonesia, Indonesia government should improve the physical and social infrastructures to drive the productivity and economic efficiency. It will increase the GDP and also attract more investors. Low interest rate policy should be considered.