• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.87-94
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• 2003

Construction plan and strength control have limitations in construction production field because it is difficult to predict the form removal strength and development of specified concrete strength. However, we can have reasonable construction plan and strength control if prediction of concrete strength is available. In this study, firstly, the newly proposed strength prediction model with maturity method was compared with the logistic model to test the adaptability. Secondly, the determination of time of form removal was verified through the new strength prediction model. As the results, it is found that investigation of the activation energy that are used to calculate equivalent age is necessary, and new strength prediction model was proved to be more accurate in the strength prediction than logistic model in the early age. Moreover, the use of new model was more reasonable because it has low SSE and high decisive factor. If we adopt new strength prediction model at construction field, we can expect the reduced period of work through the reduced time of form removal.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.85-94
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• 2009

In cost estimation of construction, several methods including quantity-per-unit costing, job costing, unit cost estimation and lumpsum estimation are being utilized in Korea. Among them, a Quantity-per-unit Costing Method is used as a standard of cost estimation in public and private works. This paper presents the realistic job-costing method on all road construction tasks through statistical analyses with field survey data to solve the problems induced by the existing quantity-per-unit costing method. Furthermore, it was found that the newly developed job costing method is able to produce a simple costing procedure and a more actual construction cost estimation by a case study, which was performed to compare particular construction costs produced by two different methods, existing quantity-per-unit costing and newly developed job costing. These methods is compared by Case-study about sub-base. In the case of Job costing method, the estimate is shorter than the other case about 50% and can make up for the weak point about instrument in the current Standard of cost estimation. And it can be depict by Job Costing method about progress of work for using by a plan about construction management.

• Korean Institute of Interior Design Journal
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• no.40
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• pp.3-9
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• 2003

Today the social concern about Interior Design gradually requires wide comprehension. Also according to demanders' requirement. Colleges cope with speed. Interior Design made by experts for the function and purpose in the conception of decoration. Therefore, Colleges are responsible to educate for more capable professional designers. But management is the first concern for Interior Design Company students are going to work at. Interior Design has not the important state yet in Korea, it is hard to manage the company with only design works on the table. As architectural design side must get some admission, design is apart from construction. but they are worked together in Interior Design. Also, as the architectural design with process detail drawings, interior design is required the detail design for construction. But it is the facts that the college is interested in and concentrated on rather education for design and space plan than intensive education for construction because of the restricted environment of practice room. I propose component and practical use of nude construction department to understand detailed design.

• Journal of the Korea Institute of Building Construction
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• v.21 no.1
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• pp.21-29
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• 2021

The objective of this study is to evaluate the effect of the application of double layered bubble sheet on the curing of slab and wall concrete placed at the job site in cold weather and to offer a feasibility of Concrete IoT Management System(CIMS), which is wireless sensor network developed by the authors, to manage early age quality of the concrete in terms of temperature, maturity and strength development. Test results indicated that the application of bubble sheet enhances the insulation performance, which results in an increase of the temperature by around 1~20. 6℃. It is found that CIMS can gather the temperature, maturity and strength development data from the sensors embedded from 30 m far from CIMS successfully. Predicted compressive strengths by CIMS had good agreement with measured ones within 2 MPa error level until 7 days. It is thought that the combination of the bubble sheet application for cold weather protection and CIMS for quality management tool in cold weather concreting contributes to shorten the time for the form removal by one day.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.54-56
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• 2002

고추는 국내 재배면적이 노지재배가 75,000 ha 정도로서 해마다 조금씩 감소하고 있고, 시설재배가 5,000 ha 정도로서 해마다 증가하고 있다. 따라서 약 80,000 ha 의 재배 면적을 매년 심어야 하기 때문에 원예작물 가운데 가장 많은 모종을 필요로 한다. 이를 뒷받침하기 위하여 공정육묘에서 차지하는 비율이 60%를 넘고 있다. 고추종자는 발아적온이 28-3$0^{\circ}C$ 정도로 알려져 있으며 발아소요일수가 2-3일 정도로서 발아적산온도는 1,300~1,450$^{\circ}$ 정도로 알려져 있다. (중략)

• Proceedings of the Korean Institute of Interior Design Conference
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• 2001.05a
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• pp.133-139
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• 2001

Today the social concern about Interior Design gradually requires wide comprehension. Also according to demanders' requirement. Universities cope with speed. Interior Design made by experts for the function and purpose in the conception of decoration. Therefore, Universities we responsible to educate for more capable professional designers. But management is the first concern for Interior Design Company students are going to work at. Interior Design has not the important state yet in Korea, it is hard to manage the company with design alone. As architecture must get admittion, design is apart from construction. but they are worked together in Interior Design. It is true that all the work of construction is Capenters' or technical engineers' work except space design. Of course students are interested in just design not in construction. Students majoring in design need wide understanding of construction not a concept design. but detailed design for construction and proper valuation ability to manage company. I propose component and practical use of nude construction department to understand detailed design.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1207-1212
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• 2006

In this study, Chemical Oxygen Demand(COD) which is the measure of organic substances, Total nitrogen(T-N), Total phosphorous(T-P), Fe and Mn were analyzed in the sediments of dam reservoir. The purpose of this study were to understand the relevances among the analytical methods adopted and the applicabilities of those methods. For the determination of COD, Standard Method for the Examination of Marine Environment(SMEME) and Standard Method for the Examination of Sanitary(SMES) was used. Both method had wide dynamic range and the deviations of the values obtained by two methods were small because $KMnO_4$ method closely reflected BOD and organic substances. For the determination of T-N and T-P, Standard Method for the Examination of Food(SMEF) and Standard Method for the Examination of Sanitary(SMES) were used. Two methods for T-N were both the acid-base titration but SMES gave less T-N values than SMEF because of the differences in digestion and distillation steps. Two methods for T-P gave the comparable values after acid digestion of $HNO_3$ and $HClO_4$. The determination of heavy metals as a Fe, Mn was mainly divided to the leaching method and acid digestion method. The values obtained by leaching method were less than those by digestion method. It is thought that the condition of acid digestion was more severe than that of leaching method.

• Clean Technology
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• v.4 no.1
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• pp.45-59
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• 1998

Continuous immobilized-cell culture was carried out for the production of kasugamycin, a secondary metabolite by a filamentous bacteria, Streptomyces kasugaensis, with an intention of reducing waste generation. A sporulation medium was developed for production of bulk amounts of spores, and the spores were entrapped into celite biosupports for immobilization. It was possible to effectively keep the immobilized-cells inside the reactor during the continuous culture by an efficient immobilized cell separator of decantor type on the outlet of the fermentor. Using this continuous immobilized-cell fermentor system, we investigated the effects of feed substrate and phosphate concentrations on kasugamycin production and chemical oxygen demand(COD). Comparing with the conventional suspended-cell batch culture, the kasugamycin productivity was observed to increase by 2.5 times, whereas COD per unit kasugamycin production decreased by 2.3 times in the continuous immobilized-cell culture. Based on these results, the continuous immobilized-cell system was considered to be a cleaner bioprocess than the conventional batch suspended-cell system.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.4
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• pp.90-96
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• 2003

This study was performed to evaluate effect of extraction mode on SVE efficiency for fuel-contaminated soil. A gas station was selected for this study. As a result of pressure test in well head, soil texture of contaminated site under the gas station was very different from site to site. SVE system was operated in intermittent mode (1hr extraction / 3hr rest) or continuous mode. Capacity of air blower was $1m^3/min$. Extration mode test was conducted in two severe contaminated sites. In both two sites, cumulative TPHgas mass of intermittent extraction mode was higher than that of continuous mode. Considering long term operation of SVE in a field, in general, it was thought that intermittent extraction mode was effective in view of vaporized TPHgas mass and electrical cost.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.897-905
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• 1994

Project Informations Classification System (PICS) can be utilized as a springboard for advanced construction management techniques because it marries informations to networks and maintains a disciplined cost control. The present study attempts to develop a PICS which can be applied in construction management techniques. The frame work largely consists of the three parts such as: (i) development of the tentative Work Breakdown Structure with three divisions, facility calssifications, functional classifications and work classifications, covering the whole areas of civil works, (ii) development of the integrated informations system including the other informations in cost estimating and network scheduling, (iii) construction of relational database system for computer application. The system suggested in the study is found useful for the systematic and uniform management of construction works in the various stages.