• Title/Summary/Keyword: Dismantling Process

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Performance Evaluation of Eco-friendly Insulating Finish According to the Addition Ratio of Granular Cork (입상 코르크 첨가율에 따른 친환경 단열마감재의 성능평가)

  • Kim, Yong-Gu;Kim, Yeon-Ho;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.148-149
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    • 2020
  • Currently, the most commonly used EPS insulation material has been mainly used because its ease of adhesion with concrete. However, due to poor adhesion with wallpaper, separate adhesion needs to be strengthened and there are cases of breakage or grooves in the process of dismantling the mold. The biggest problem is that when a fire breaks out, various harmful substances are present and highly flammable. Cork used in this study is a truly eco-friendly building material that is taken from between the outer and inner bark of cork trees and does not damage the wood. Also, it is a porous material that is made up of countless cells and contains an air gap between the cells. It is very light in weight between 0.06 and 0.07 and has excellent insulation with a heat conductivity of 0.04W/mK. In addition, it has high stability in the topic of conversation because it does not produce harmful gas when burned and has self-sustaining properties. However, research on cork, an eco-friendly building material with excellent performance to date, is scarce Therefore, we encourage existing scholars to raise interest in new eco-friendly building materials through this study. It also aims to manufacture insulation boards with new inorganic properties using the low weight and heat conductivity held by the cork.

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The Qualitative study about parent's in law of multiculture family - Hermeneutical grounded theory methology - (다문화 가족 시부모들에 대한 연구 -해석학적 근거이론 방법 접근-)

  • Kim, Young Sook;Lee, Keun Moo
    • Korean Journal of Social Welfare Studies
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    • v.42 no.2
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    • pp.41-70
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    • 2011
  • This research is to study the interaction of multiculture parents in law between. daughter in law. We approached hermeneutical grounded theory and six of multiculture family's parent's in law participated this research. Data were collected by the depth interview and various written records and we could construct 9 hermeutical theme by analyzing and categorizing 83 meaning units, 22 categories. We descripted the process of acculturation between parent's in law and daughter in law. The result as follows : ① sticking self dimensions → ② strategic acceptomce → ③ making shade of co-existence → ④ self dismantling and reconstruction. Finally we proposed the 「joint program of parent's in law and daughter in law for reinforcing culture unpetence」.

A comparative study of different radial basis function interpolation algorithms in the reconstruction and path planning of γ radiation fields

  • Yulong Zhang;Jinjia Cao;Biao Zhang;Xiaochang Zheng;Wei Chen
    • Nuclear Engineering and Technology
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    • v.56 no.7
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    • pp.2806-2820
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    • 2024
  • Accurate reconstruction of radiation field and path planning are very important for the safety of operators in the process of dismantling nuclear facilities. Based on radial basis function (RBF) interpolation algorithm, this paper discussed the application of inverse multiquadric radial basis Function (IMRBF) interpolation method to the reconstruction of gamma radiation field, and proved the feasibility of reconstructing a radiation field with multiple γ sources. The average relative errors of IMRBF interpolation results were 4.28% and 8.76%, respectively, for the experimental scenarios with single and double gamma sources. After comparing the consistency between the simulated scene and the experimental scene, IMRBF method and Cubic Spline method were respectively used to reconstruct the gamma radiation field by Geant4 simulation data. The results showed that the interpolation accuracy of IMRBF method was superior to that of Cubic Spline method. Further, more RBF interpolation algorithms were used to reconstruct the multi-γ source radiation field, and then the Probabilistic Roadmap (PRM) algorithm was used to optimize the human walking path in the radiation field reconstructed by different interpolation methods. The optimal paths in radiation fields generated by multiple interpolation methods were compared. The results herein contribute to a comprehensive understanding of RBF interpolation methods in reconstructing γ radiation fields and their application in optimizing paths in radiation environments. The insights may provide valuable information for decision-making in radiation protection during the decommissioning of nuclear facilities.

A Study on Segmentation Process of the K1 Reactor Vessel and Internals (K1 원자로 및 내부구조물 절단해체 공정에 대한 연구)

  • Hwang, Young Hwan;Hwang, Seokju;Hong, Sunghoon;Park, Kwang Soo;Kim, Nam-Kyun;Jung, Deok Woon;Kim, Cheon-Woo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.4
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    • pp.437-445
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    • 2019
  • After the permanent shutdown of K1 in 2017, decommissioning processes have attracted great attention. According to the current decommissioning roadmap, the dismantling of the activated components of K1 may start in 2026, following the removal of its spent fuel. Since the reactor vessel (RV) and reactor vessel internal (RVI) of K1 contain massive components and are relatively highly activated, their decommissioning process should be conducted carefully in terms of radiological and industrial safety. For achieving maximum efficiency of nuclear waste management processes for K1, we present activation analysis of the segmentation process and waste classification of the RV and RVI components of K1. For RVI, the active fuel regions and some parts of the upper and lower active regions are classified as intermediate-level waste (ILW), while other components are classified as low-level waste (LLW). Due to the RVI's complex structure and high activation, we suggest various underwater segmentation techniques which are expected to reduce radiation exposure and generate approximately nine ILW and nineteen very low level waste (VLLW)/LLW packages. For RV, the active fuel region and other components are classified as LLW, VLLW, and clearance waste (CW). In this case, we suggest in-situ remote segmentation in air, which is expected to generate approximately forty-two VLLW/LLW packages.

Treatment of AP Solutions Extracted from Solid Propellant by NF/RO Membrane Process (NF/RO 멤브레인 공정을 적용한 고체추진제에서 추출된 암모늄 퍼클로레이트 (AP) 처리 연구)

  • Kong, Choongsik;Heo, Jiyong;Yoon, Yeomin;Han, Jonghun;Her, Namguk
    • Membrane Journal
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    • v.22 no.4
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    • pp.235-242
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    • 2012
  • Ammonium perchlorate (AP) is primarily derived from the process of liquid incineration treatment when dismantling a solid rocket propellant. A series of batch dead-end nanofiltration (NF) and reverse osmosis (RO) membrane experiments were conducted to explore the retention mechanisms of AP under various hydrodynamic and solution conditions. Low levels of silicate type of siloxane had been detected through the GC/MS and FTIR analysis of liquid solutions extracted from solid ammonium perchlorate composite propellant (APCP). It is indicated that NF/RO membranes fouling in the presence of APCP was mainly attributed to the AP interactions because the concentration of silicate type of siloxane was negligible compared to that of AP. The osmotic pressure of AP was presumably resulted in the flux declines ranging from 13 to 17% in the case of the application of low-pressure (551 and 896 kPa for NF and RO) compared to those in application of high-pressure. The retention of AP by NF/RO membranes significantly varied from approximately 10 to 70% for NF and 26 to 87% for RO, depending on the operating and solution water chemistry conditions. The results suggested that retention efficiency of AP was fairly increased by reducing concentration polarization (i.e. application of low-pressure and stirring speed of 600 rpm) and increasing the pH of a solution. The result of this study was also consistent with the previous modeling of 'solute mass transfer of NF/RO membranes' and demonstrated that hydrodynamic and solution water chemistry conditions are to be a key factor in the retention of AP by NF/RO membranes.

An Experimental Study on the Performance and Field Application of Low Noise Beam-slab Formwork using Table Type Multi-stage Drop System (테이블형 다단 드롭 시스템을 이용한 저소음 보-슬래브 거푸집의 구성부재 성능 및 현장적용에 관한 실험적 연구)

  • Ryu, Hwa-Sung;Jeong, Woo-Jin;Kim, Deuck-Mo;Song, Seong-Yong;Shin, Sang-Heon
    • Journal of the Korea Institute of Building Construction
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    • v.17 no.4
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    • pp.349-360
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    • 2017
  • In concrete construction work, formwork is an important process that accounts for 10% of the total construction cost. Recent buildings are becoming bigger and higher. In order to maximize the efficiency and safety of this formwork, the system of formworking has been systematized. However, the human accidents and the noise complaints arise from dismantling processes frequently occur. In order to solve these problems, most of them are dependent on foreign technology, but they do not take into consideration the conditions of domestic construction site. In this study, we developed a table type multi-drop system form for a slab and beam which can improve the process, safety and reduction of disassembly noise, and evaluated the physical properties of the main members which are used in the system. The results of this study show that there is sufficient strength to be used as a slab and a laying material for both a yoke beam and a supporting post. The noise level is improved compared to existing method.

Formation of Efflorescence and Dissolving Experiments for Removing Control on the Stone Pagoda of the Mireuksaji Temple Site, Iksan, Korea (익산 미륵사지 석탑의 백화현상과 제어를 위한 용출실험)

  • Lee, Dong-Sik;Lee, Chan-Hee;Kim, Sa-Dug
    • Journal of Conservation Science
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    • v.19
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    • pp.5-18
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    • 2006
  • The Mireuksaji stone pagoda of the Iksan was built in Muwang King of Baekjae Kingdom and has maintained its present status through several rebuilding process. Recently, the structural unbalance of the pagoda has worsened, so for scientific maintenance recovery of its original pagoda form, the pagoda is under dismantling process. The original form of this pagoda is being presumed to be a plane square pagoda of nine stories, though only a portion of six stories remains until today. The destroyed part from collapse was liked in insecure pagoda form by Japanese in year of 1915. On the surface of the stone which has gone through the present time, efflorescence appeared as precipitation substance over crusted and due to this phenomenon, the structure and color of thee original stone haven't been preserved. Therefore, quantitative analysis on its kind, emitted status and contamination type of secondary inorganic contamination substance of the over crusted surface were analyzed. Also through reaction experiments, contamination type was defined and tests have been applied to find the requirements that will wash out the contaminants. The result of this study will provide the base of quantitative analysis on the kind of inorganic contamination of the surface of stone assets, and it shall also contribute to the application of scientific maintenance recovery of surface cleaner for efflorescence.

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Level of Lead in Air and Blood Zinc Protoporphyrin of Workers in Lead Plants (연 취급 노동자의 연 폭로 수준 및 혈중 Zinc Protoporphyrin 농도)

  • 김창영
    • Journal of Environmental Health Sciences
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    • v.17 no.1
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    • pp.95-103
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    • 1991
  • For the purpose of estimating the working environment and the relationship between the airborne lead concentration and the ZPP level in the whole blood of the workers, the airborne lead concentrations and the ZPP level were measured at the 26 plants which deal with lead, from October 5 to November 5 in 1988. Analysis of the airborne lead concentration was performed by NIOSH Method 7082, and the ZPP level was measured by a hematofluorometer. The following results are concluded. 1. The average airborne lead concentration of the lead battery manufactures is 0.025mg/m$^{3}$ and that of the secondary lead smelters is 0.023mg/m$^{3}$. There were no significant differences between industry (p>0.1) 2. At the lead battery manufacture, the process of lead powder production showed the highest concentration of 0.034mg/m$^{3}$ but there were no significant differences among the processes (p>0.1). At the secondary lead smelter, the process of dismantling waste batteries showed the highest concentration 0.141mg/m$^{3}$, and there were very significant differences among the processes (p<0.005). 3. The ZPP level in the whole blood showed significant differences between industry (p<0.10). The average ZPP level of the lead battery manufactures is 133.0 + 106.3 $\mu$g/100ml and that of the secondary lead smelters is 149.6 + 110.9 $\mu$g/100ml. 4. The correlation coefficients between the airborne lead concantration and ZPP level were 0. 426 (p<0.001) for the lead battery manufactures and 0.484 (p<0.001) for the secondary lead smelters. The correlation coefficients between the work duration (in months) and the ZPP level were 0.238 (p<0.001) for the lead battery mannfactures and 0.075 (p>0.10) for the secondary lead smelters. 5. The linear regression equation, with the airborne lead concentration as an independent variable and the ZPP level as a dependent variable, is Y=96.84+1300.34X (r=0.448, p<0.001) for the 26 plants which deal with lead. The linear regression equation, with the work duration(in months) as an independent variable and the ZPP level as a dependent variable, is Y=127.28 +0.49X (r=0.162, p<0.05). 6. The correlation coefficients between the amount of inhaled lead and ZPP level were 0.349 (p < 0.001) for the lead battery manufactures and 0.318(p<0.001) for the secondary lead smeltes. The linear regression equation for the 26 plants surveyed, with the amount of inhaled lead as an independent variable and ZPP level as a dependent variable, is Y=123.63+18.82X (r=0. 335, p<0.001).

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A Study on the Influencing Factors for the Establishment of a Public Asset Management System Based on AHP-ISM (AHP-ISM기반의 공공자산관리 관리체계 영향요인 도출 연구)

  • Lee, Han-Sol;Lee, Ung-Kyun
    • Journal of the Korea Institute of Building Construction
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    • v.22 no.4
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    • pp.403-414
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    • 2022
  • Many studies have been conducted on asset management of public facilities, as the importance of such management has been increasing. This basic study aims to present strategies for the practical use of public asset management, and seeks to propose efficient management and utilization measures from a cost perspective by comparing and analyzing the importance and impact relationship between cost items for public asset management. In this study, 19 sub-items and the top 4 items were chosen by deriving cost factors based on the previous literature. A survey was conducted, and the results of the survey were analyzed by using the Analytic Hierarchy Process(AHP) and Interpretive Structural Modeling (ISM) methods. The AHP was used to derive the priority between items, and ISM was used to identify major groups and mutual influences. As a result, those items showing both high priority and high importance, such as user cost, dismantling/disposal cost, replacement cost, maintenance/repair cost, etc. are determined as priority items to be considered for public asset management of public facilities. Also, it is necessary to minimize the impact on other items in public asset management by those items which are impacted less by other items but have significant impact on the items such as initial construction costs, conceptual design costs, construction costs, and supervision costs. It is expected that the results and analysis methods presented in this study can be used to provide strategies for asset management of public facilities.

A Study on Efficient Deconstruction of Supporters with Response Ratio (응답비를 고려한 효율적인 버팀보 해체방안에 관한연구)

  • Choi, Jung-Youl;Park, Sang-Wook;Chung, Jee-Seung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.469-475
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    • 2022
  • As the recent structure construction is constructed as a large-scale and deep underground excavation in close proximity to the building, the installation of retaining wall and supporters (Struts) has become complicated, and the number of supporters to avoid interference of the structural slab has increased. This construction process becomes a factor that causes an increase in construction joints of a structure, leakage and an increase in wall cracks. In addition, this reduced the durability and workability of the structure and led to an increase in the construction period. This study planned to dismantle the two struts simultaneously as a plan to reduce the construction joints, and corrected the earth pressure by assuming the reaction force value by the initial earth pressure and the measured data as the response ratio. After recalculating the corrected earth pressure through the iterative trial method, it was verified by numerical analysis that simultaneous disassembly of the two struts was possible. As a result of numerical analysis applying the final corrected earth pressure, the measured value for the design reaction force was found to be up to 197%. It was analyzed that this was due to the effect of grouting on the ground and some underestimation of the ground characteristics during design. Based on the result of calculating the corrected earth pressure in consideration of the response ratio performed in this study, it was proved analytically that the improvement of the brace dismantling process is possible. In addition, it was considered that the overall construction period could be shortened by reducing cracks due to leakage and improving workability by reducing construction joints. However, to apply the proposed method of this study, it is judged that sufficient estimations are necessary as there are differences in ground conditions, temporary facilities, and reinforcement methods for each site.