• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.11
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• pp.600-605
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• 2013

Ground source heat pump systems (GSHP) can achieve higher performance of the system, by supplying more efficient heat source to the heat pump, than the conventional air-source heat pump system. But building clients and designers have hesitated to use GSHP systems, due to expensive initial cost, and uncertain economic feasibility. In order to reduce the initial cost, many researches have focused on the energy-pile system, using the structure of the building as a heat exchanger. Even though several experimental studies for the energy-pile system have been conducted, there was not enough data of quantitative evaluation with economic analysis and comprehensive analysis for the energy-pile. In this study, a prediction method has been developed for the energy pile system with barrette pile, using the ground heat transfer model and ground heat exchanger model. Moreover, a feasibility study for the energy pile system with barrette pile was conducted, by performance analysis and LCC assessment. As a result, it was found that the heat exchange rate of a barrette pile was 2.55 kW, and the payback period using LCC analysis was 8.8 years.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.6
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• pp.795-810
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• 2019

In this paper, The study was conducted on the method to roughly determine the area and length of the multi-utility tunnel before the planning and design phase of the multi-utility tunnel construction. For this purpose, four feasibility indexes were used: traffic density, population density, disaster prevention index (number of workers), and urbanization rate, which reflect the regional characteristics. The installation criteria were set in consideration of the average value and minimum value of the feasibility indexes for the tunnel type among areas that can be installed in the multi-utility tunnel of Seoul. The analysis area included 200 areas based on 14 zones. The results of the analysis based on the minimum value of feasibility indexes indicated that the tunnel type of multi-utility tunnel is suitable for 39 areas with high traffic volume and population. On the other hand, the 'gun' area, etc., has a wider population than the 'si' and 'gu', suggesting that it is not suitable to install multi-utility tunnel. In addition, it can be seen that the larger the index value centered on the minimum value of each index, the smaller the tunnel type of multi-utility tunnel installation area.

• Journal of Korean Library and Information Science Society
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• v.45 no.4
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• pp.409-428
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• 2014

The purpose of this study is to analyze the economic feasibility of Busan Regional Central Library. The four candidate sites were included for the analysis. To achieve the purpose of this study, we applied three types of indices such as Benefit-Cost analysis, Net Present Value, and Internal Rate of Return. We used CVM(Contingent Valuation Method) to calculate the benefit; we conducted two investigations to calculate WTP, which are for pretest and for main survey. From results of pretest, we designed five optimal prices. On the basis of them, main survey was accomplished to figure out WTPs for four candidate sites. The results show that four candidate sites were all feasible from an economic point of view. Of these, the Busan Citizen Park site got the highest point of B/C ratio.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.445-453
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• 2017

The Korean government's recent R&D policy has focused on encouraging government-funded research institutes (GRIs) to develop mid-term, long-term, and large-scale R&D projects. It is necessary to prepare thoroughly for the new R&D strategy, but there is no systematic accumulation of planning expertise, and there has been continued demand for good examples of research planning. Therefore, this study analyzes the reports of preliminary feasibility for government R&D programs through a meta-analysis of detailed evaluation items and contents to help researchers enhance their project-planning ability. The evaluation items that can be applied to R&D planning for GRI were reviewed, and twelve detailed evaluation items were selected through content analysis. The results of this study could contribute to practical R&D project planning and the improvement of evaluations.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.47-55
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• 2013

PURPOSES : This study aimed to evaluate the feasibility of AASHTO86 design method for Bonded Concrete Overlay. METHODS : The Feasibility of AASHTO86 design method for Bonded Concrete Overlay is investigated based on the following study : i) Sensitivity analysis of designed service life of Bonded Concrete Overlay by major design input for AASHTO86 guide. ii) Comparison of actual Bonded Concrete Overlay life and predicted Bonded Concrete Overlay life by AASHTO86. iii) Finding the stress component influence the potential distress of Bonded Concrete Overlay based on 3-d FEM analysis. iv) Exploring the limitation of AASHTO86 in the aspect of design input. RESULTS : Sensitivity analysis showed that the condition of existing pavement significantly on the Bonded Concrete Overlay life. Also the overlay thickness affect the Bonded Concrete Overlay life. The comparison of actual Bonded Concrete Overlay life and predicted Bonded Concrete Overlay life showed relatively good agreement when the early distress sections are excluded in comparison. Bonding stress occurred at the interface may be larger than the bond strength used in the specification of Bonded Concrete Overlay construction. CONCLUSIONS : Bonded Concrete Overlay life predicted by the AASHTO86 may not be reliable. Number of points to improve the reliability in the design of Bonded Concrete Overlay are suggested in this study.

• Environmental and Resource Economics Review
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• v.24 no.1
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• pp.85-107
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• 2015

This study analyzes the effect of applying hyperbolic social discount rate onto the results of benefit-cost analysis of environmental public investment projects in Korea. In order to check the application possibility to the actual feasibility study, the discount factors generated by hyperbolic function, rather than traditional exponential one, would be applied to the benefit and cost data from the pre-feasibility studies which peformed for environmental public investment projects. The results of this study shows that using hyperbolic social discount rate is effective for enhancing test results, only under the condition of which the full expansion of the time periods of analysis is satisfied. According to the simulation results of this study, to achieve higher benefit/cost ratio by using hyperbolic social discount rate, the period should be increased up to 120 to 150 years at least.

• Journal of the Korean Society for Railway
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• v.15 no.2
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• pp.179-184
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• 2012

Environmental impact is getting more attention in many feasibility studies for railroad-related projects and research items. For sustainable growth and green transportation, the benefits typically used for feasibility studies in railway-related projects, are composed mostly of economic criterions which is not considering growing attention on changing paradigm. Based on the analysis of current methodologies, improvements in estimating environmental impact especially on noise and pollution are suggested. Active steering bogie has been proposed to satisfy stabilizing and steering performance of railroad. This paper describes the feasibility study of the active steering bogie for a urban railway vehicle based on environment-related criteria.

• Journal of Gastric Cancer
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• v.19 no.4
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• pp.438-450
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• 2019

Purpose: Although linear-shaped gastroduodenostomy (LSGD) was reported to be a feasible and reliable method of Billroth I anastomosis in patients undergoing totally laparoscopic distal gastrectomy (TLDG), the feasibility of LSGD for patients undergoing totally robotic distal gastrectomy (TRDG) has not been determined. This study compared the feasibility of LSGD in patients undergoing TRDG and TLDG. Materials and Methods: All c: onsecutive patients who underwent LSGD after distal gastrectomy for gastric cancer between January 2009 and December 2017 were analyzed retrospectively. Propensity score matching (PSM) analysis was performed to reduce the selection bias between TRDG and TLDG. Short-term outcomes, functional outcomes, learning curve, and risk factors for postoperative complications were analyzed. Results: This analysis included 414 patients, of whom 275 underwent laparoscopy and 139 underwent robotic surgery. PSM analysis showed that operation time was significantly longer (163.5 vs. 132.1 minutes, P<0.001) and postoperative hospital stay significantly shorter (6.2 vs. 7.5 days, P<0.003) in patients who underwent TRDG than in patients who underwent TLDG. Operation time was the independent risk factor for LSGD after intracorporeal gastroduodenostomy. Cumulative sum analysis showed no definitive turning point in the TRDG learning curve. Long-term endoscopic findings revealed similar results in the two groups, but bile reflux at 5 years showed significantly better improvement in the TLDG group than in the TRDG group (P=0.016). Conclusions: LSGD is feasible in TRDG, with short-term and long-term outcomes comparable to that in TLDG. LSGD may be a good option for intracorporeal Billroth I anastomosis in patients undergoing TRDG.

• Environmental and Resource Economics Review
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• v.15 no.4
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• pp.693-712
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• 2006

A pre-feasibility test is done for renewable energy hybrid power systems at off~grid islands in which the current power supply is provided only by diesel generation. We apply Homer (Hybrid Optimization Model for Electric Renewables) which was developed by the National Renewable Energy Laboratory (NREL) for the analysis to identify the cost-minimizing combination of power generating facilities for the given load profiles. Chuja-Do, Geomun-Do and Youngsan-Do have been selected for our analysis considering the wind resources data of the Korea Institute of Energy Research (KIER). Information on wind speed, solar radiation and temperature is also used for the analysis. System component cost information from overseas market has been used due to the lack of domestic information. Site specific Load profile for electricity demand for those islands are reconstructed based on the partial survey results obtained form other sources. The LCOE of the least cost hybrid power systems for Chuja-Do, Geomun-Do and Youngsan-Do are $0.278/kWh, $0.234/kWh and $0.353/kWh, respectively Considering the fact that diesel generation is being subsidized at the price of $0.300/kWh by the government, first 2 cases are economically feasible for the introduction of renewable energy hybrid systems to those islands. But the third case of Youngsan-Do does not meet the criteria. The basic differences of these pre-feasibility test results are from the differences of the site specific renewable energy conditions, especially wind resources. In summary, promoting hybrid systems in the off-grid remote island should be based on the economic feasibility test results. Not all the off-grid islands are feasible for introducing this renewable energy hybrid system.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.31-41
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• 2015

The telecommunication industry has been considered as a national fundamental infrastructure. However, due to the rapid evolution of technology and the change of industry market conditions, the telecommunication infrastructure needs no more huge space for facility and it leads its use to the mixed-use development based on private investment. This study intends to examine the financial feasibility of the development project for the optimal alternative use of telecommunication facility purpose site as a case study based on two types: contributed acceptance and multi-level designation. The NPA and IRR has been analyzed by the simulation of stochastic variables including rent price and its variation rate, vacancy rate, construction cost, capitalization rate and discount rate. The research finding indicates that the two types of development are satisfied with the financial feasibility and it is noteworthy that the rent price turns out to be the most critical factor for the project. Accordingly, it is expected that these research finding can be applied for providing the solid cases of financial feasibility analysis for the development project in limited use of telecommunication facility purpose site.