• Explosives and Blasting
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• v.38 no.4
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• pp.16-25
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• 2020

Multi-setting smart-investigation of the ground and large uncharged hole boring (MSP) method to reduce the blast-induced vibration in a tunnel excavation is carried out over 50m of long-distance boring in a horizontal direction and thus has been accompanied by deviations in boring alignment because of the heavy and one-directional rotation of the rod. Therefore, the deviation has been adjusted through the boring machine's variable setting rely on the previous construction records and expert's experience. However, the geological characteristics, machine conditions, and inexperienced workers have caused significant deviation from the target alignment. The excessive deviation from the boring target may cause a delay in the construction schedule and economic losses. A deep learning-based prediction model has been developed to discover an ideal initial setting of the MSP machine. Dropout, early stopping, pre-training techniques have been employed to prevent overfitting in the training phase and, significantly improved the prediction results. These results showed the high possibility of developing the model to suggest the boring machine's optimum initial setting. We expect that optimized setting guidelines can be further developed through the continuous addition of the data and the additional consideration of the other factors.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.1
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• pp.41-51
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• 2024

If an underground accident occurs, the cause must be quickly identified and human and material damage reduced. The Underground Accident Investigation Committee is responsible for identifying the causes of accidents and preparing response plans to prevent similar accidents from occurring in the future. The law stipulates that the Underground Accident Investigation Committee can operate from a minimum of 6 months to a maximum of 9 months after an accident occurs. However, the operation schedule of the Underground Accident Investigation Committee seems difficult to cite the accident investigation report to the construction project currently in progress at the same time project. In this study, the Underground Accident Investigation Committee seeks to establish a strategy for developing technology that can shorten data collection and analysis, which previously took 3 months, to less than 1 month. As a result of the research, five areas of technology development identified, ground data collection and transmission technology, ground safety data generation technology, digital twin-based underground safety analysis and visualization technology, digital twin-based geo-ambulance construction and operation technology, and digital twin-based geo-ambulance standardization and legal system. research was able to be conducted. If the proposed technology is developed, it is expected to contribute to reducing accident scenes through faster decision making than before.

• Korean Journal of Construction Engineering and Management
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• v.22 no.4
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• pp.59-65
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• 2021

Since the 2016 "Housing Act Partial Amendment" and the "2018 Housing Comprehensive Amendment Plan", interest in the pre sale system and post sale system of apartment houses has been on the rise. In order to compare the advantages and disadvantages of the pre sale system and the post sale system of apartment houses, and to establish the basis for the institutional policy of the post sale system, a questionnaire survey method was used for tenants of the apartment house from the public side, and issues of time and cost. The time series analysis method is intended to suggest an appropriate time for payment of contributions. Accordingly, through a review of existing theories and literature, the post sale system of public and private institutions was organized, and through a questionnaire survey, the path to securing pre sale money, product information of the model house, and the degree of awareness of the effect of the post sale system were investigated. For the post sale fund support and payment method, it is necessary to increase the commercial line for existing financiers from the user's point of view, and it is necessary to operate in consideration of the economic power of the pre sale market by region. Both 60% post sale and 80% post sale have a price range of up to KRW 10 million, and the total interest rate is 5.0%, and the annual interest rate is about 2.8% for 60% post sale, and about 2.1% for 80% post sale, which is lower than the current 3.1%. I need an interest rate. The research is a perception survey targeting a total of 5,213 households in a sample of after sale apartments in public institutions. As the actual values are analyzed using a time series on the effects of market supply and demand and market prices, there is a limit to applying them to prospective residents of private apartments. In addition, to respond to first time tenants, a questionnaire survey was conducted on five complexes that have moved in within the last five years.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3184-3190
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• 2013

These days, the great part of design processes in the field of ship or offshore manufacturing are planed and implemented using the customized CAD system for each ship-building companies. It means that all information for design and production could be extracted and reused at the useful other area cost considerable time and efforts. The representative example is the estimation of welding length and material amount which is demanded during the construction of ship or offshore structures. The proper estimation of welding material to be used and the usage of them at the stage of schedule planning is mostly important to achieve the seamless process of production and expect the costing in advance. This study is related to the calculation of welding length and needed material amount at the stage of design complete utilizing the CAD system. The calculated amount are classified according to welding position, stage, block, bevel and welding type. Moreover it is possible to predict the working time for welding operation and could be used efficiently for the cost management using the results of this research.

• Spatial Information Research
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• v.23 no.1
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• pp.1-8
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• 2015

The purpose of this study is to develope BIM Template according to major building material for efficiently and quantitatively evaluating greenhouse gas emission at the design stage. Template users consider various environmental impacts without connecting simulation tools for analyzing environmental impact and Template users who have no prior knowledge can Life Cycle Assessment by using The green template. For this study, Database which was reflected in template was constructed considering environmental performance. and 6 kinds of environmental impact categories and PPS standard construction codes were analyzed by major building material derived from literature. Based on this analyzed data, The major Material Family according to the main building material was developed. When users conduct modeling by utilizing Family established, evaluating result can be confirmed in the Revit BIM Modeling program by using the schedule function of the Revit. Users through the modeling, the decision-making environment performance possible. In addition, we propose to create a guideline for the steps required to build an additional established family.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.46
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• pp.29-60
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• 2010

The incentive and reasons to publish FIDIC Conditions of Contract for Design, Build and Operate Projects(DBO Form) are manifold. It is partly a response to the increasing need for sophisticated project delivery methods in both the public and private sectors and the already widespread use of the FIDIC Yellow Book with operation and maintenance obligations and partly a response to the challenge to decrease maintenance cost to a minimum by means of a new procurement route. As a result, FIDIC has developed a new model form to meet this market place requirement. On the other hand, FIDIC did not simply adapt the Yellow Book but has developed a new form from it, whilst preserving the style of the already known FIDIC Forms and maintaining the wording where it was not necessary to change it for the purposes of a DBO Form. Moreover DBO Form fills up supposed gaps in other FIDIC Forms and ameliorates the claim management and dispute management framework. FIDIC DBO approach may be shortly summarized as follows. First, DBO Form provides for single project responsibility. Second, DBO Form has the clear objective of ensuring the use of a most reliable and efficient technology at the lowest life-cycle cost. Third, DBO Form is intended to operate as an effective quality increase in the design and construction of projects. Fourth, DBO Form is intended to provide significant benefits with regard to system integration and reduction of risks. Fifth, DBO Form accelerates and enhances completion schedule compliance. Sixth, DBO takes care of all three supporting pillars of sustainability(including economical, environmental and social elements). DBO Form is obviously a good starting point for negotiations and the preparation of calls for tenders, thus saving the parties time and money. However, existing cultural and legal differences, particular local conditions and the particular needs of some branches of the industry may require the form to be adapted according to the particular needs of a project. And Civil law practitioners are strongly recommended to verify carefully the underlying legal concepts and background of each clause of the General Conditions in order to avoid unnecessary and sometimes unnatural changes and amendments being made. Note that when preparing the Particular Conditions ensure that terminology is consistent and that existing inherent concepts should not be ignored.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.41-48
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• 2004

We may consider the inducement of demand to public transportation as a solution to relieve traffic congestion and pollution. Subway has merits as moving on schedule, transporting more people than bus. But subway is required a vast investment in the early stage of construction has a huge debt. So it runs into red figures, and on this account, services of subway are falling more and more. Development of subway's operation cost function is useful to understand structure of subway's operation and catch the relations of operation cost and actual results. In addition, we can present the policy that is a helpful to the operation as development of operation cost function. But there are short of studies about operation cost deal with a subway comparison with local train. Because local train has many lines and data, on the other hand, subway has one to four lines and less data. Most of previous studies sought the operation cost function of Seoul. So this study aimed to develop and apply the operation cost function of Seoul, Incheon, Busan and Daegu area using full allocation method. In this study, we considered the number of passengers, track-km, train-km, revenue as actual results. By appling the operation cost function, we compared the average cost of each city and confirmed the existence of economies of scale about the number of passengers, train-km.

• Journal of the Korean Geotechnical Society
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• v.28 no.8
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• pp.5-19
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• 2012

Vertical drains along with the preloading technique have been commonly used to enhance the consolidation rate of dredged placement formation. In practice, vertical drains are usually installed in the process of self-weight consolidation of a dredged soil deposit because this process takes considerable time to be completed, which makes conventional analytical or numerical models difficult to quantify the consolidation behavior. In this paper, we propose a governing partial differential equation and develop a numerical model for 2-D axisymmetric non-linear finite strain consolidation considering self-weight consolidation to predict the behavior of a vertical drain in the dredged placement foundation which is installed during the self-weight consolidation. In order to verify the developed model in this paper, results of the numerical analysis are compared with that of the lab-scaled self-weight consolidation test. In addition, the model verification has been carried out by comparing with the simplified method. The comparisons show that the developed model can properly simulate the consolidation of the dredged placement formation with the vertical drains installed during the self-weight consolidation. Finally, the effect of construction schedule of vertical drains and of pre-loading during the self-weight consolidation is examined by simulating an imaginary dredged material placement site with a thickness of 10 m and 20 m, respectively. This simulation infers the applicability of the proposed method in this research for designing a soil improvement in a soft dredged deposit when vertical drains and pre-loading are implemented before the self-weight consolidation ceases.

• Journal of Radiation Protection and Research
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• v.15 no.2
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• pp.113-122
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• 1990

After four years of planning, equipment acquisition, facility construction and beam testing, the KCCH cyclotron facility was put into operation in November1986. Now the KCCH cyclotron(MC-50) has been used for four years in neutron therapy and radioisotope production. Up to December 1989, 179(1852 sessions) patient have undergone neutron therapy. Radioisotope production for nuclear medicine use was started from March 1989 after extensive work to overcome target transport, target melting, beam diagnostic and chemical processing problems. This status report introduces the cyclotron facility, and the experiences of neutron therapy and isotope production with the MC-50 cyclotron. Besides, the operation results and the general troubles of the MC-50 during 1989 are summarized. Total operation time was 1252.5 hours. Four hundred hours were used for neutron therapy of 599 treatment sessions and 832.5 hours for radioisotope production. Total amount of produced raioisotope was 1695 mCi(Ga-67 : 1478mCi, Tl-201 : 107 mCi, I-123 : 25mCi, In-111 : 85mCi). Twenty hours were used for scheduled beam testing. In 1989, 882% of the planned operation were performed on schedule and this rats is improved remarkably compared to 71.0% in 1988.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1171-1180
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• 2018

Korea's water transmission system is operated by the nonpressure flow method that flows from highlands to lowlands due to the nature of Korea with many mountainous areas. In order to store water in the highlands, the water pumps are installed and operated. However, In this process, a lot of electrical energy is consumed. therefore, it is necessary to minimize the energy consumption by optimizing the size and operation schedule of the water pumps. The optimal capacity and operation method of the water pump are affected by the size of the tank (distributing reservoir). Therefore, in order to economically design and operate the water transmission system, it is reasonable to consider both the construction cost of the water pump and the tank and the long-term operation cost of the water pump at the step of determining the scale of the initial facilities. In this study, the optimum design model was developed that can optimize both the optimal size of the water pump and the tank and the operation scheduling of the water pump by using the genetic algorithm (GA). The developed model was verified by applying it to the water transmission systems operated in Korea. It is expected that this study will help to estimate the optimal size of the water pump and the tank in the initial design of the water transmission system.