• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.444-447
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• 2006

Construction managers need to pay a close attention to the resource utilization in order to deliver the construction project successfully. Construction scheduling is crucial for resource control in that it provides information when and how much to bring down work force to sites. In scheduling, activity duration is projected based on the productivity of historical data or the intuition of scheduler. This paper studies the opportunity of applying cost-based productivity for estimating activity duration. For cost-based productivity, the cost of resource is used as an input and the work quantities as an output. Out of historical data, regression model has been developed to understand the validity of applying cost-based productivity in projecting activity duration. The result of study will work as a prerequisite for implementing the environment of database-based construction scheduling.

• Journal of the Society of Disaster Information
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• v.7 no.4
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• pp.294-304
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• 2011

Disaster prevention resources consist of persons, equipments, goods, and facilities. Specially, equipments and goods are internally managed in the regional office, and may be leased to the inter-offices. National Disaster Management System(NDMS) managed the resources in the separated system. That is, one system is managed by regional disaster prevention system, the other is managed by the central disaster prevention system which receives the data from the regional disaster prevention system. Because the regional disaster prevention system updates the resource information quarterly, it is difficult to confirm the exact information. In this study, we propose the model which makes to supply in timely the resource to the disaster using the managed resource with RFID technology. Firstly, we classified the resources based on the resource types for the easily search. After then, we defined ID and attributes information of the resources. From the information, we described the management model for the real time resource.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.144-147
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• 2011

동시다발적인 산불발생시 한정된 진화자원을 효과적으로 운영하여 산불피해를 최소화하기 위해서는 산불상황에 맞는 진화자원 투입과 배치가 이루어져야 한다. 이를 위해서는 진화자원 투입 및 운영 의사결정을 할 수 있도록 각 진화자원별 진화능력단위에 대한 평가가 이루어져야 한다. 하지만 아직 국내 외적으로 산불진화자원에 대한 진화능력단위 산정에 관한 연구가 이루어져 있지 않다. 따라서 본 연구에서는 우리나라 진화자원을 중심으로 진화능력단위 기준 설정과 함께 각 진화자원별 진화능력단위를 산정하였다. 우리나라 진화자원은 크게 지상진화자원과 공중진화자원으로 구분됨으로 지상진화에 투입되는 주요 진화자원인 등짐펌프 및 불갈퀴 등 손도구를 이용하는 진화인력과 산불진화차량, 이동식 동력살수장치와 산불진화헬기로 구성되는 공중진화자원에 대해 진화효과를 분석, 능력단위를 산정하는 방법을 제시하였다.

• Journal of Energy Engineering
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• v.28 no.4
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• pp.61-75
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• 2019

This article analyzed the direct impact of resource inputs on business performances of Korean environmental companies conducting R&D, and the mediation effects of product-, process-, organization-, marketing-innovations between resource inputs and business performances. We conducted the mediation analysis using SPSS and Process Macro, based on a survey data from the Korean environmental companies. The article found that ① resource inputs have directly had a positive impact on business performances, and ② innovations have mediated them. ③ But among 4 types of innovations, the only mediation effect of organization-innovation has been verified, and the others have not appeared. Considering the above results, the following policy implications can be suggested. ① It is necessary to reinforce related policies so that companies can improve business performances through innovation. ② The government needs to carry out the prudent supporting policies so that innovations in product, process, and marketing can lead to business performances. This article has the limitation of using the survey data, and needs further researches on the sectoral system of innovation for Korean environmental industry.

• Environmental and Resource Economics Review
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• v.28 no.3
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• pp.415-435
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• 2019

The purpose of this study is to analyze the returns to scale by estimating the bigeye tuna production function of Korean distant longline fisheries in WCFPC waters. In the analysis, number of crews, vessel tonnage, number of hooks, and bigeye tuna biomass are used as input variables and the catch amount of bigeye tuna is used as an output variable in the Cobb-Douglas production function. Prior to the function estimation, the biomass of bigeye tuna was estimated by the Bayesian state-space model. Results showed that the fixed effect model was selected based on the hausman test, and vessel tonnage, hooks, and biomass would have direct effects on the catch amount. In addition, it was shown that the bigeye tuna distant longline fisheries in WCFPC water would have increasing returns to scale.

• Journal of the Society of Disaster Information
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• v.9 no.2
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• pp.153-163
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• 2013

The damage caused by natural and human disasters has been increasing year by year. While the damage from these disasters are unavoidable, reduction of damage level by proper establishment of control measures could be sufficiently achievable. Disaster prevention resources include resources introduced in the event of disaster, such as human, materials, equipments and facilities. Rapid yet proper inputs of these resources are the key factor to minimize any damages from the disaster. Currently, however, the standard and/or criteria for mobilization of the disaster prevention resources have not yet systematically established. Therefore, proper resource management as well as efficient resource input has not been in place. This research is an early stage construction of efficient mobilization resources, which had been irregularly loaded and applied before. Also this study has tried to provide a classification rule for efficient disaster prevention resource management and mobilization, and indeed, provide a foundation for efficient resource management system.

• Environmental and Resource Economics Review
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• v.6 no.2
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• pp.209-231
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• 1997

본 논문은 전통적인 산업연관분석이 고정투입계수를 시용하고 있어서 상대가격체계의 변화에 따른 경제 주체들의 비용최소화 노력을 모형 내에 반영하지 못하고 있다는 한계를 극복하기 위하여 상대가격체계의 변화에 따라 가변투입계수를 갖는 "반복다중최적화(IMO) 모형"을 이용하여 탄소세 부과가 가격구조에 미치는 영향을 분석하였다. 분석 결과는 고정투입계수모형에 비하여 가격인상효과는 전반적으로 낮게 나타났으며, 특히 에너지집약산업은 고정투입계수모형에 비하여 가격상승률이 낮게 나타난 반면, 기타산업은 가격상승폭이 높게 나타났다. 이러한 결과는 에너지원에 대한 탄소세의 부과효과가 상대가격변화에 적응한 경제주체들의 비용최소화 노력으로 각 산업으로 분산된 결과라 여겨진다.

• Environmental and Resource Economics Review
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• v.15 no.4
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• pp.673-692
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• 2006

In order to test for the dynamic optimality condition for the use of nonrenewable resource, it is necessary to estimate the shadow value of the resource in situ. In the previous literatures, a time series for in situ price has been derived either as the difference between marginal revenue and marginal cost or by differentiating with respect to the quantity of ore extracted the restricted cost function in which the quantity of ore is quasi-fixed. However, not only inconsistent estimates are likely to be generated due to the nonmalleability of capital, but the estimate of marginal revenue will be affected by market power. Since firms will likely fail to minimize the cost of the reproducible inputs subject to market prices under realistic circumstances where imperfect factor markets, strikes, or government regulations are present, the shadow in situ values obtained by estimating the restricted cost function can be biased. This paper provides a valid methodology for checking the dynamic optimality condition for a nonrenewable resource by using the input distance function. Our methodology has some advantages over previous ones: only data on quantities of inputs and outputs are required; nor is the maintained hypothesis of cost minimization required; adoption of linear programming enables us to circumvent autocorrelated errors problem caused by use of time series or panel data. The dynamic optimality condition for domestic coal mining does not hold for constant discount rates ranging from 2 to 20 percent over the period 1970~1993. The dynamic optimality condition also does not hold for variable rates ranging from fourth to four times the real interest rate.

• Resources Recycling
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• v.30 no.4
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• pp.11-19
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• 2021

Arsenic (As) oxidation followed by precipitation from a high-As(III)-containing leaching solution derived from a sulfidic ore was investigated in this study to remove aqueous As from the solution using activated carbon (AC) with air injection as an oxidant. To obtain the initial leaching solution, a domestic sulfidic ore was leached in a sulfuric acid solution at pH 1 and 50℃ for 95 h, and approximately 7 g/L of Fe and 3 g/L of As were leached out. To determine the effect of the oxidative reaction utilizing AC with air injection, the leaching solution was tested under the following five oxidative conditions at an initial pH of 1 and 90℃ for 72 h: air-only injection; air injection with 1, 5, and 10 w/v% of AC addition; and H₂O₂ addition. The tests in the presence of both air and AC revealed that the oxidation kinetics and As removal were improved by the reaction between the metallic species and the surface group formed on the AC surface. In addition, the greater the amount of AC added, the better was the reaction efficiency, removing 93-94% of As with more than 5 w/v% of AC addition. Finally, X-ray diffraction analysis confirmed that the precipitate formed from the oxidative reaction was scorodite (FeAsO₄·2H₂O).

• Economic and Environmental Geology
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• v.54 no.5
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• pp.573-580
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• 2021

This study analyzed the induced effects of the aggregate and stone sectors using the industry association table. First, the added value of the aggregate and stone sectors was summarized, and then the intermediate input structure and induced effect were analyzed. In terms of value-added structure, aggregate and stone showed a higher employee remuneration rate compared to the manufacturing industry, and a higher rate of operating surplus compared to other mining industries. The intermediate input structure summarizes the sector using aggregate and stone products as intermediate inputs and their input ratio. The proportion of the intermediate element input structure was confirmed. In addition, the main input sectors of ready-mixed concrete, the largest consumer of aggregate and stone, are also summarized. The production-inducing effect of aggregate and stone showed a higher influence coefficient than the sensitivity coefficient, confirming that they had a relatively large rear chain effect. The production inducement effect was reviewed by reconstructing the industry association table, and it was found to show a relative superiority in the influence coefficient, similar to the results derived according to the provisional classification of the Bank of Korea.