• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.353-358
• /
• 2001

Since the financial crisis broke out, liquidity has become the critical issue in housing construction industry. In order to secure liquidity, it is prerequisite to precisely forecast cash flow. However, construction companies have failed to come up with a systematic process to manage and forecast cash flow. Until now, companies have solely relied on the prediction of profits and losses, which is carried out as they review business feasibility. To obtain more accurate cash flow forecast model, practical pattern of payments should be taken into account. In this theory, basic model that analyzes practical housing payment collection pattern resulting from prepayments and arrears is described. This model is to complement conventional cash flow forecast scheme in the phase of business feasibility review. Analysis result on final losses in cash that occur as a result of prepayment and arrears is considered in this model. Additionally, in the estimation of construction cost in the phase of business feasibility review, real construction prices instead of official prices are applied to enhance accuracy of cash outflow forecast. The proportion of payment made by a bill and changes in payment date caused by rescheduling of a bill are also factored in to estimate cash outflow. This model would contribute to achieving accurate cash flow forecast that better reflect real situation and to enhancing efficiency in capital management by giving a clear picture with regard to the demand and supply timing of capital.

• Journal of Korea Water Resources Association
• /
• v.40 no.12
• /
• pp.995-1005
• /
• 2007

This study presents a framework for optimum scale determination for small hydropower development in a river basin. The framework includes the construction of hydrology and topography data, the simulation of hydropower operation, the economic analysis, and the determination of optimum scale of the small hydropower. The optimum scale of design flow and facility are determined by Net Present Value among economic analysis indices. The investment cost is estimated by the cost function derived from the construction cost of existing small hydropower plants. The benefit from power generation is estimated by the price announced by government. The presented framework is applied to the two potential sites in Cho River basin for the dam and run-of-river type of plants. Finally, the sensitivity analysis for a design flow and scale of the plant is performed for the each site. The usage of the framework presented in the study is highly expected for the estimation of potential hydropower resources or the decision support tool for a proprietor by estimating the optimum scale and economical feasibility in advance.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.2
• /
• pp.221-229
• /
• 2020

As the cosmetics beauty industry grows into a key next-generation industry, the establishment of an industrialization center is needed, but failure to verify the adequacy and feasibility of the investment could lead to financial burdens. In this study, the project costs and facilities of an industrial center are reviewed to analyze its economic feasibility based on the cost estimates, revenue estimates, estimated profit or loss calculations, and estimated operating cash flows. The profit estimation criteria were analyzed by applying 90 per cent of expected orders for research projects (24 billion won) and 12 per cent of rental rates for testing equipment (4.5 billion won for construction), and the benefit/cost ratio is higher than 1.02 per cent and the net present value is higher than '0' won, and the internal rate of return is also more than 5.06 per cent for all three analytical methods. Therefore, in order for the construction of a cosmetics beauty industrialization center to be economically feasible, it is necessary to maintain research project orders of more than 90 percent and return on equipment rent of more than 12 percent, and a strategic approach is needed to diversify business profits.

• Journal of the Society of Disaster Information
• /
• v.17 no.3
• /
• pp.608-616
• /
• 2021

Purpose: Safety inspections by existing personnel have been limited in evaluation and data securing due to concerns about the safety of technicians or difficulty in accessing them, and are becoming a bigger problem as the number of maintenance targets increases due to the aging of facilities. As drone technology develops, it is possible to ensure the safety of personnel, secure visual data, and diagnose quickly, and use it is increasing as safety inspection of facilities by drones was introduced recently. In order to further enhance utilization, it is considered necessary to base a consideration standard for facility appearance investigation by drones, and in this paper, research was conducted on dams. Method: To calculate the quality, existing domestic safety inspection and drone-related consideration standards were investigated, and procedures related to safety inspection using drones were compared and analyzed to review work procedures and construction types. In addition, empirical data were collected through drone photography and elevation image production for the actual dam. Result: Work types for safety inspection of facilities using drones were derived, and empirical survey results were collected for two dams according to work types. The existing guidelines were applied for the adjustment ratios for each structural type and standard of the facility, and if a meteorological reference point survey was necessary, the unmanned aerial vehicle survey of the construction work standard was applied. Conclusion: The finer the GSD in appearance investigation using drones, the greater the number of photographs taken, and the concept of adjustment cost was applied as a correction to calculate the consideration standard. In addition, it was found that the problem of maximum GSD indicating limitations should be considered in order to maintain the safe distance.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.2
• /
• pp.143-152
• /
• 2008

In order to share the understanding agricultural multifunctionality with people, we carried out quantification and monetary evaluation for controlling flood and fostering water resources function in paddy and upland farming in Korea. The amount of water controlling flood and fostering water resources function in paddy farming was much greater than that in upland. The quantification of flood control function could be estimated by sum of the height of dike and water infiltrated during the flooding periods in paddy farming, and water excepting runoff water from precipitation at flooding time in upland farming. As results of estimation of flood control function, the amounts of water controlling flood have been evaluated as $294mm\;year^{-1}$ in paddy farming and $72.6mm\;year^{-1}$ upland farming, and was calculated 3.71 billion MT on a nation basis in 2006. When it was carried out monetary estimation as the cost of dam construction and the depreciation expense by using replacement cost method, flood control functions in paddy and upland were evaluated as 44,338.9 and 7,221.5 billion won, respectively. Comparing with previous reports, monetary value was analyzed much to increase because of rising price cost recently. Fostering water resource functions were also quantified in paddy and upland farming as the amount of water keeping and infiltrating water during the cultivation. In the basis of estimation model, it was showed that paddy and upland farming had been estimated to have $414.28mm\;year^{-1}$, $18.7mm\;year^{-1}$, respectively. They were also calculated to 4.49 and 0.137 billion MT on a nation basis in 2006, respectively. The economic values of fostering water resources function in paddy and upland farming were also estimated to 1,769.4 and 52.8 billion won, respectively, as replacing the amount of water to the cost of drinking water in 2006. There were differences by much to the amounts of controlling flood function and fostering water resource between paddy and upland farming. It means that paddy farming more play an important role in environment than upland farming in Korea.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.32 no.4B
• /
• pp.233-242
• /
• 2012

In the past, the domestic water supply benefit of dam has been estimated by replacement dam cost approach. But it is logically inappropriate that we use the second priority dam as a replaced facility. Therefore, this study aims to suggest the estimation method of the domestic water supply benefit by using demand function, which is deduced from Willingness-To-Pay (WTP) of consumers. For this purpose, a survey concerning the marginal WTP is carried out according to the change of water use amount used, targeted 1,000 households in metropolitan area. And by using the marginal WPT, we estimated the demand function of a family. Finally, the monthly benefit equation is derived. The approach is demonstrated and discussed for an example, the Song-Li-Won dam project which is now renamed Young-Ju dam. From the example study, the total benefit for the durable years (50 years), was about 90 billion won. The method proposed herein is expected to be practical and useful in the economic analysis of the domestic water supply project including dam construction, as well as in further studies.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.9 no.4
• /
• pp.89-98
• /
• 2001

Present vermicomposting technology needs the broad land. Because of the high land cost, the land saving technology such as multistage must be needed. And present operation practices are mostly based on human power, mechanization and automation is needed. Also, present control practices based on individual experience need the scientific base control system. Even though the rough estimation of organic waste treatment showed that vermicompostiong could obtain more benefits than costs. But, the estimation is based on an ideal case without considering the technical and market. Generally, vermicomposting is considered as the more expensive technology than composting. Therefore, the practical proof the economic factor would be the most important to the market increase. Vermicomposting as the recycling technology has better condition than incineration and landfill. Propagation and advocating focused on its environmentally sound aspects would be needed continuously. Especially, demonstration and distribution of household vermicomposting would be a good approach. Vermicomposting facilities area was becoming larger, and earthworm feeding materials were also expanding to various organic sludges. These trends showed that vermicomposting is being enlightened to treat and recycle the organic wastes.

• Journal of the Korean Society for Railway
• /
• v.20 no.2
• /
• pp.288-298
• /
• 2017

The system of high-speed and conventional railway vehicles is diversified, and significant technological development in performance has been achieved. This study analyzed the modal change characteristics; furthermore, it estimated the value of travel time by improving the travel time and cost for the passenger's perception of railway. In this study, we formulate a mode choice model for passengers and compare it with the mixed logit model which reflects individual taste variation. In addition, the validity of the analysis is presented through an estimation the value of travel time using the derived model. For this purpose, a stated preference survey was conducted with 510 people using public transportation. The benefits of time-saving can be accurately determined by estimating the value of time spent on the railway. Appropriate fares for public transportation can also be estimated.

• Korean Journal of Construction Engineering and Management
• /
• v.9 no.2
• /
• pp.182-189
• /
• 2008

In private and public construction works, cost estimation and site productivity management are based on designed labor quantities calculated by the Standard Quantities per Unit (SQU). The designed labor quantities are regarded as the basis for insurance costs and safety and environmental costs and also affect the progress measurement of construction works. Even though the designed labor quantities from the SQU has been considered to be different from actual labor quantities put to construction works, there is no research that empirically analyzes the statistical differences. This study analyzes actual labor quantities of form workers, steel-bar fabricators, concrete pourers in reinforced concrete works of the 43 apartment projects, and compares the actual labor quantities to labor quantities from the SQU. It goes further to scrutinize the critical reasons underlying the differences through a survey on 65 practitioners and interviews with 32 site managers and supervisors. The regression models of labor quantities of the apartment concrete work produced by the present study will contribute to reasonable construction contracts based on the past actual costs and practical site management by the actual labor quantities.

• Journal of the Korean Society for Library and Information Science
• /
• v.56 no.3
• /
• pp.265-290
• /
• 2022

An economic evaluation was conducted using cost-benefit analysis for an integrated service platform of open access research articles. The data needed for benefit measurement were collected by conducting a series of surveys to service beneficiaries, including 1,313 academic researchers, 49 bio-industry researchers, and 102 researchers in various industries. Cost-benefit analysis and sensitivity analysis were conducted after estimating the total costs for system construction and operations, anticipated direct and indirect benefits. With respect to the cost-benefit analysis limited to direct benefits, the estimated benefit was KRW 82 billion, which is about 14 times of the total costs for eight years of the entire business period. With respect to the cost-benefit analysis for both direct and indirect benefits, BCR was estimated to be about 98.9 and NPV to be KRW 538.8 billion, indicating that economic feasibility of the project was sufficiently secured. The results of this analysis may help securing the investment to the integrated service platform for OA research products, and the benefit estimation model developed in this study would be utilized as an assessment tool during the rest of this project.