• Korean Journal of Construction Engineering and Management
• /
• v.10 no.6
• /
• pp.146-153
• /
• 2009

The year 2008 was a hard year for Korea's construction companies. The real estate downturn resulted in halting new construction and stopping existing work, and inflation of global oil prices caused price hikes in rebar and concrete materials. As a solution to reducing the budget, the newly appointed government announced plans to increase low cost bid contracts from 10 billion to 30 billion won. When such economical and political factors negatively impact the construction market, projects based on low cost contracts are the hardest hit. Many problems already inherent in low cost bid contracts become accentuated. Consequently, this provides an opportune time to actually study and analyze the issues in these projects. This paper introduces the findings made from investigating four projects struggling to make ends meet in the year 2008. Results show that flow of cash (i.e., liquidity), or lack thereof, was the root cause which in turn was hampered by failed mechanisms for design changes, material inflation. Attributing cash flow risk to the bottom of the production structure (i.e., small business subcontractors) was also a problem within the industry. Contractors need a better way to prepare against material price fluctuations, and owners need to assist in expediting payment during times of extreme downturn.

• Tunnel and Underground Space
• /
• v.10 no.4
• /
• pp.506-515
• /
• 2000

A lot of underground construction projects have been conducted by economical, social and military purposes in Korea for the last three decades. As a result, magnificent amount of data were obtained from geological site investigations, laboratory and field tests, design and field monitoring. But up to now, these valuable informations were neither systematically stored nor utilized efficiently resulting in a great loss of time and money. In this study, a database system named GeoINFO was developed using Microsoft Access 97 for management of informations which can be obtained from underground construction. The developed database system is especially designed to cover three major types of underground facilities-tunnels, underground storages and rock slopes and has multi-layered tree structures for data input. The system also has a unique indexing system for efficient data search using Visual Basic code.

• Journal of the Korean Institute of Gas
• /
• v.18 no.4
• /
• pp.35-43
• /
• 2014

Usage of the inorganic floor finishing material can be advantageous to overcome some problems of traditional organic-based floor finishing material used for hazardous material storage facilities. A spark can be produced by physical impact between the flooring and the flooring disposal equipment while removing the existing flooring. In order to prevent a fire hazard, which may be caused the spark, it is feasible that a construction can be implemented without removing the existing flooring. Moreover, the top coating material containing an antistatic agent is effective to prevent secondary damage caused by static electricity after finishing the construction of the flooring. Therefore, the inorganic floor finishing material of the this study is expected to be beneficial for safety management and economical aspect for inspectors.

• Journal of KIISE:Information Networking
• /
• v.27 no.2
• /
• pp.175-186
• /
• 2000

Over the years, the extensive use of networks and distributed systems has increased the need for authentication and digital signatures. Inperforming authentication on a massive scale, authentication servers that use multiple workstations or PCs are more economical than servers that use one inicomputer or mainframe. However, the establishment of authentication servers with multiple platforms can cause some security problems and increases the cost of key management because all platforms within the server must have the private key of the authentication server. We propose a scheme which can solve these problems. The proposed scheme can establish a strong authentication server with no additional key management and improve the performance of the authentication server up to 13 times.

• Journal of Korean Society of Forest Science
• /
• v.94 no.3 s.160
• /
• pp.168-177
• /
• 2005

To provide the basic policy informations for environment-friendly and economical construction of green forest road, forest road density considering for the forest terrain and characteristics was computed. As results, designing the effective forest management and protection, standard forest road density as a social overhead capital (SOC) concept was computed to 8.57 m/ha. Considering as based facilities for forest management, we also optimal forest road density for preparing the sustainable forest management system was computed to 14.01 m/ha.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.30 no.1D
• /
• pp.27-36
• /
• 2010

Recently, the management of metro business in large cities has become more difficult because of increased construction and operation costs. The purpose of this paper presents the construction of transfer system to resolve about recent tendency to decrease of metro-users and diminution of use efficiency which are serious problems of Busan metro. To cope with this situation, it is necessary to examine the methods of obtaining returns on development profits of land value rises that occur due to transfer system construction between Busan metro line #1 and line #2 in Yangsan area. Therefore, it was made use of research on metro utilization to presuppose service improvement, as an alternative, in the transfer system construction between metro and metro which might be powerful influence over metro-users. In this research, it was examined the actual situation of rises in land values brought about by the transfer system construction of metro line #1 and line #2 in Yangsan area with application of four (4) methods, and have calculated a basis of the development profits produced by the transfer system construction of metro line. According to the economical efficiency analysis, the total construction cost amount to 4,827.1 billion won of case #1 based on single track, and evaluate economically as B/C to 1.013, NPV to 72.7 billion, IRR to 5.614 percent.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.5
• /
• pp.108-116
• /
• 2022

Started in 1989 as Public Permanent Rental Housing scheme, public rental housing lease policy is increasing target residents and supply in each government by introducing new supply types. However, public housing business entities have difficulties in expanding the supply due to cumulated deficit. The research suggested long-term public rental housing reconstruction business as a method to preserve the cumulated deficit from the previous. Minimum floor area ratio mathematical model was suggested by defining the floor area ratio of reconstruction business as minimum, since housing sales profit after reconstruction could preserve aggregated deficit, and mathematically approached by considering the traits of long-term public rental housing reconstruction. The determinant for minimum floor area ratio mathematical model comprise cumulated deficit of the existing long-term public rental housing, land size of reconstructed sale housing, housing sales price per unit area, and business cost per unit area. Minimum floor area ratio mathematical model is expected to be the milestone for supporting decision making regarding the economic part of old long-term public lease housings' reconstruction scale, and expanding housing supply within urban area.

• Korean Journal of Construction Engineering and Management
• /
• v.19 no.2
• /
• pp.38-49
• /
• 2018

Since the ratification of the Paris Agreement (COP21), the government is continuously strengthening policies for the reduction of greenhouse gas of the construction industry in accordance with the growing importance of reducing greenhouse gas and obligation of the government. Especially, the government emphasizes the need to improve the energy performance of old public buildings. Since 2014, the government is running a pilot project in which the government supports the construction cost of the green remodeling project of old public buildings and it is intended to develop the best practice of green remodeling and activate the green remodeling in the private sector. In this study, we analyzed the economical efficiency of the old public buildings by each level through green remodeling and conducted building related investigation and equipment measurement to plan the alternatives of the corresponding buildings. The improvement plan is a green remodeling plan that integrates alternatives. Five improvement plans were developed for each level to analyze the economic feasibility of each plan. As for the analysis method, the first energy demand amount calculation and the LCC analysis were performed through ECO2. In the LCC aspect, the improved 3/4 plan (middle level plan) was the most excellent and results were obtained in the order of the highest cost plan followed by the lowest cost plan. As a result, it is expected that it can be utilized as a basic data for future green remodeling performance plan and economic feasibility analysis in the future.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.04a
• /
• pp.389-394
• /
• 2004

Structure-typed cultural heritage, objects of preservation are positioned as one of the very important heritage in the nation, and the preservation of prototypical structures become influential in national development and against natural disaster. For this reason, Digital Close Range Photogrammetry has recently been diversely used. Despite its popular use, the measurement has limits that make it unsuitable for photographing precise cultural heritage situated at high mountainous terrain or where people can not approach easily. These high gigantic stone statues are among the preserved structure-typed cultural heritage. In order to supplement the limits, when using the measurement, a camera tripod with +30m, a ladder truck and a shore should be equipped, which means additional equipment leads to it being a waste of cost and time. In this vein, a device was developed in detail, using a RC Helicopter installed with a CCD video camera with ease of control, safety, equipment, carrying, movement and approach, then checked image shot by a wireless modem at real time and considered the economical efficiency without re-photographing. Next, the author digitized the images of the nationally designated structure-typed cultural heritage, used materials on their restoration as the third dimension in order to construct the integrated management-information system for cultural heritage. Through the above processes, this study can provide specific information on 3D images and 3D CAD sections of structured-typed cultural heritage for both the public and specialists on the web. Moreover, it suggests the foundation to restore the damaged cultural heritage in the future by aiming for their effective management and preservation.

• Journal of Digital Convergence
• /
• v.11 no.8
• /
• pp.41-52
• /
• 2013

Recently in Korea, it takes place as a social phenomenon the emergency of small family(1-2 persons). The City-Type Housing is constructed new standards and facilities for them from 2009. P.O.E(Post Occupancy Evaluation) carried out the building for a period of time, making the assessment says. The aims of this study were P.O.E. of the City-Type Housing and its political implications. Four City-Type Housing located Gang-Nam, Gang-Buk in Seoul, surveyed 62 questions and interviewed for City-Type Housing office. As the results revealed transportation issues, confined space, parking space, economic issues. In Gang-Nam resident were more satisfactoried the location, the building status, the construction status, the housing size, maintenance and economical sences 95% confidence level. Thus, it should be improved. the upward limited living space, parking space qualified, defined design technical issues.