• Journal of the Korean Institute of Educational Facilities
• /
• v.9 no.3
• /
• pp.5-12
• /
• 2002

This study attempts to suggest a standard for maintenance and repair cost per each unit area, by analyzing the causes and cost of various maintenance and repair work in the university facilities. The result of my study on the data of maintenance and repair work for 12 years between 1990 and 2001 in the two campuses of the university that I selected for my case study is the following. (1) The yearly average for maintenance and repair cost in the facilities of the university with 67 old and new buildings for the past 12 years was $W4,422/m^2$. In addition, the repair cost based on the calculation of the degree of decrepitude of the buildings was $W10,291/m^2$. (2) The number of causes of maintenance and repair work increase steadily every year, due to the development of universities and changes in the educational environment. A special case like a university merger also appears, which also demands maintenance and repair work of university facilities. (3) It is important that a budget for interior maintenance is increased or added to an extent, in order to minimize the maintenance and repair cost of the university facilities, and to cope with changing educational environments flexibly. (4) The publication of a white paper that includes the planning of a building, construction process, and changes in design, seems to be required for the sake of users' convenience and efficient maintenance and repair work.

• Proceedings of the SAREK Conference
• /
• 2005.11a
• /
• pp.148-154
• /
• 2005

Ground-source (Geothermal) heat pump (GSHP) systems can achieve a higher coefficient of performance than conventional air-source heat pump (ASHP) systems. However, GSHP systems are not widespread in Japan because of their expensive boring costs. The authors have developed a GSHP system that employs the cast-in-place concrete pile foundations of a building as heat exchangers in order to reduce the initial boring cost. In this system, eight U-tubes are arranged around the surface of a cast-in-place concrete pile foundation. The heat exchange capability of this system, subterranean temperature changes and heat pump performance were investigated in a foil-scale experiment. As a result, the average values for heat rejection were 186${\sim}$201 W/m (for pile, 25 W/m per Pair of tubes) while cooling. The average COP of this system was 4.6 while cooling; rendering this system more effective in energy saving terms than the typical ASHP systems. The initial cost of construction per unit for heat extraction and rejection is ${\yen}$72/W for this system, whereas it is f300/W for existing standard borehole systems.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.6 s.144
• /
• pp.673-678
• /
• 2005

IMO adopted ' International Convention for The Control and Management of Ships' Ballast Water and Sediments ' on February 13th 2004. According to this convention, a ballast water treatment system should be installed in all ships obligatorily up to a standard date. When the system is installed, economic propriety should be considered. The economic propriety analysis examines the profit of a relevant project which can be presented by a equation, (Profit) = (income) - (expense) - (tax). However, the ballast water system is not for the profit during the life cycle but for the satisfaction of the regulation. Therefore, the expense should be minimum against the profit. This study presents the LCC(Life-Cycle Cost) analysis for economic evaluation of several ballast water system of foreign products.

• Structural Engineering and Mechanics
• /
• v.81 no.1
• /
• pp.93-102
• /
• 2022

The optimum design of reinforced concrete cantilever retaining walls subjected to seismic loads is an extremely important challenge in structural and geotechnical engineering, especially in seismic zones. This study proposes an adaptive sperm swarm optimization algorithm (ASSO) for economic design of retaining structure under static and seismic loading. The proposed ASSO algorithm utilizes a time-varying velocity damping factor to provide a fine balance between the explorative and exploitative behavior of the original method. In addition, the new method considers a reasonable velocity limitation to avoid the divergence of the sperm movement. The proposed algorithm is benchmarked with a set of test functions and the results are compared with the standard sperm swarm optimization (SSO) and some other robust metaheuristic from the literature. For seismic optimization of retaining structures, Mononobe-Okabe method is employed for dynamic loading conditions and total construction cost of the structure is considered as the single objective function. The optimization constraints include both geotechnical and structural restrictions and the design variables are the geometrical dimensions of the wall and the amount of steel reinforcement. Finally, optimization of two benchmark retaining structures under static and seismic loads using the ASSO algorithm is presented. According to the numerical results, the ASSO may provide better optimal solutions, and the designs obtained by ASSO have a lower cost by up to 20% compared with some other methods from the literature.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.102-112
• /
• 2001

It has been passed $5\~6$ years since Construction Management introduced in Korea, but a few government projects have been presented as CM instances. We performed CM service, on behalf of the foreign Client, in the Insa-dong construction, I-Project. Even though there were many limits in cost, time and other aspects, we have attained satisfaction of the Client and successful businesses of all the construction parties as adopting the advanced management methods. Many advanced construction methods have been applied for the purpose of time reduce, cost save and quality assurance as well as to the webbased project management has been imported to overcome the limits of time and place. They have actualized to increase the productivity of the project by managing the floor to floor cycle and quality systemically pursuant to ISO 9002, and by adopting Real-name construction and completion system (or individual activity. While carrying out this project, it is possible to establish mutual reliability and understanding enable to resolve the issues occurring in the early stage due to insufficient understanding of CM, lack of communications and team work, indistinct work scope through continuos training and conferences. Additionally, we became to share business targets among the parties and promoted the project in confidence. We wish that the success of I- project to be rated as a standard model of CM in Korea.

• Journal of Ocean Engineering and Technology
• /
• v.34 no.3
• /
• pp.208-216
• /
• 2020

The Integrated Offshore Standard Specification (IOSS) involves Korean shipyards, classification societies, research institutes, the Korean industrial society, engineering companies, and oil companies with the objective of reducing costs and risks without compromising safety in international offshore engineering procurement construction (EPC) projects using new standardized bulk components and qualification procedures. The activities of the IOSS include the analysis of the existing rules and regulations to achieve the best standardization, which is reflected in the best practices, and minimize the variables in regulations and rules. In addition, a standard inventory of shapes and dimensions, referred to as specifications, is proposed in the IOSS. In this paper, the aluminum tertiary standardization part (IOSS S102-1/2 S104: Specification for Structural Tertiary Design) is presented with the details of the procedures, background reviews, and cost-benefit analyses of the design and verification methods for standard designs in the IOSS standardization items. Based on the cost-benefit analysis, the application of standardized aluminum tertiary items to offshore projects has significant advantages in terms of maintenance and repair compared to the carbon steel tertiary items utilized in current industrial practices.

• Journal of Digital Convergence
• /
• v.15 no.1
• /
• pp.181-189
• /
• 2017

The purpose of this research is to set a standard for deciding competitive marketing prices of new supplying apartment houses and to analyze decision factors in sale price of supplying apartment houses with Analytic Hierarchy Process; the resulted model does not use the method that joins the land cost and the cost of construction together, but the method that compares the sales prices of surrounding apartments. This research tries to set a standard for decision of the prices of newly supplying apartment houses by classifying the determinants into the $1^{st}$ step(4 factors), the $2^{nd}$ step(9 factors), and the $3^{rd}$ step(25 factors). According to the process, the relative importance of decision factors in the sale prices is determined and this should be used as the index of sale prices for newly supplying apartment houses when the houses are provided. In addition, through the $2^{nd}$ step including 9 factors, the comparative model for sale prices is defined and the model is presented to be applied in the real business. Subsequent study additionally considering the factors apart from marketing which tries to find a generalized standard needs to be conducted.

• Advances in concrete construction
• /
• v.11 no.1
• /
• pp.19-32
• /
• 2021

In the present experimental study, the high performance hybrid fiber reinforced concrete (HPHFRC) is prepared using the Modified Andreasen and Andersen (A&A) particle packing model. Total of 16 trial mixes of HPHFRC with Indian standard sand (SS) and natural river sand (NS) are prepared to achieve the selection criteria (flow percent>150 and compressive strength>80 MPa). Based on the flow percent and compressive strength criteria, the selected mixes evaluated to study the effect of usage of natural river sand (NS) and the expensive Indian standard sand (SS) on the mechanical, durability, and microstructure property of designed HPHFRC. It has been found that the Modified A&A model is reliable to design the mix for HPHFRC with excellent mechanical, durability, and microstructure properties. In addition to that, a moderate difference in the mechanical and durability properties of NS contained HPHFRC and SS contained HPHFRC is found. Based on the obtained results of NS contained HPHFRC, it can be concluded that the use of natural river sand (NS) can be successfully adopted for the production of HPHFRC, resulted in a reduction of the production cost without compromising the excellent performance of HPHFRC.

• Journal of the Korea Institute of Building Construction
• /
• v.10 no.3
• /
• pp.91-97
• /
• 2010

Recently, as a countermeasure to the buoyancy of a building, the use of permanent drainage methods have been on the increase, and these provide benefits both in terms of economical feasibility and efficiency. When a permanent drainage method is applied, some underground water can drain out. Korea has been designated by PAI (Population Action International) as a water-stressed country, and the use of outflowing groundwater is required for the efficient oversight of water resources. However, the evaluation process on the practical use of underground water is currently insufficient. Therefore, the amount of outflowing groundwater put to practical use and the standard for the water quality were examined in this research, with the aim of establishing anappraisal process on the practical use of underground water drainage. In addition, standards for the assessment of the treatment process and the application cost of underground water drainage were developed. On this basis, an evaluation process on the use of outflowing groundwater was developed and applied inthe field. The application result proved that it was possible to assess the initial investment cost and the maintenance and management cost in the field, and thesecan be compared to the costs when supplied water is used, which makes it possible to apply in the field.

• Journal of the Korea Institute of Building Construction
• /
• v.20 no.4
• /
• pp.375-382
• /
• 2020

Rock drop obstacles on major roads in the border area in South Korea has been installed and operated to prevent and block the movement of enemy units. However, the increase in traffic volume due to the development of the border region causes many problems such as road traffic congestion due to rock drop, traffic safety, and impaired urban aesthetics. Therefore, this study aimed to provide guidelines for demolition and replacement facility installation for rock drop obstacles, which are differently applied to each unit, and to suggest the direction of the Ministry of National Defense's policy regarding maintenance cost for necessary rock drop obstacles required for operation. In this study, as part of a guideline study on the removal of rock drop obstacles and the installation of alternative facilities, a standard unit price was suggested for essential rock drop obstacles, so as to be used as judgment data when deciding whether to remove rock drop obstacles.