• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.1
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• pp.79-87
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• 2018

The purpose of this study was to analyze factors influencing insulation performance of inorganic Autoclaved Lightweight Concrete(ALC) sandwich wall panels with the application of shear connectors. To analyze the effect of shear connectors on the thermal performance of sandwich wall panels, heat transfer analysis was conducted by using the three-dimensional heat transfer simulation software. Four types of shear connector such as Pin, Clip, Grid, and Truss were selected for insulation performance analysis. Thermal bridge coefficient was calculated by varying typical panel thickness and shear connector thickness and materials such as steel, aluminum, and stainless steel. The results showed that Grid and Truss type widely distributed along the section of sandwich wall panel had a great influence on the thermal bridge coefficient by changing the influence factors. Based on the results of thermal and structural performance analysis, effective heat transmission coefficient of the sandwich wall panel satisfying the passive house insulation criteria was calculated. As a result, it was found that heat transmission coefficient was increased from $0.132W/m^2{\cdot}K$ to $0.141{\sim}0.306W/m^2{\cdot}K$ depending on the shear connector types and materials. In the majority of cases, the passive house insulation criteria was not satisfied after using shear connectors. The results of this study were likely to vary according to how influence factors were set, but it is important to apply the methods that reduce the thermal bridge when there would be a possibility of greatly affecting the insulation performance.

• Safety and Health at Work
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• v.7 no.1
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• pp.63-71
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• 2016

Background: Construction painters have not been studied well in terms of their hazards exposure. The objective of this study was to evaluate the exposure levels of total volatile organic compounds (TVOCs) for painters in the construction industry. Methods: Activity-specific personal air samplings were carried out in three waterproofing activities [polyurethane (PU), asphalt, and cement mortar] and three painting activities (epoxy, oil based, and water based) by using organic-vapor-monitor passive-sampling devices. Gas chromatograph with flame ionization detector could be used for identifying and quantifying individual organic chemicals. The levels of TVOCs, by summing up 15 targeted substances, were expressed in exposure-index (EI) values. Results: As arithmetic means in the order of concentration levels, the EIs of TVOCs in waterproofing works were 10.77, 2.42, 1.78, 1.68, 0.47, 0.07, and none detected (ND) for indoor PU-primer task, outdoor PU-primer task, outdoor PU-resin task, indoor PU-resin task, asphalt-primer task, asphalt-adhesive task, and cement-mortar task, respectively. The highest EI for painting works was 5.61 for indoor epoxyprimer task, followed by indoor epoxy-resin task (2.03), outdoor oil-based-spray-paint task (1.65), outdoor water-based-paint task (0.66), and indoor oil-based-paint task (0.15). Assuming that the operations were carried out continuously for 8 hours without breaks and by using the arithmetic means of EIs for each of the 12 tasks in this study, 58.3% (7 out of 12) exceeded the exposure limit of 100% (EI > 1.0), while 8.3% (1 out of 12) was in 50e100% of exposure limit (0.5 > EI > 1.0), and 4 tasks out of 12 were located in less than 50% of the limit range (EI < 0.5). Conclusion: From this study, we recognized that construction painters are exposed to various solvents, including carcinogens and reproductive toxins, and the levels of TVOC concentration in many of the painting tasks exceeded the exposure limits. Construction workers need to be protected from chemical agents during their painting works by using personal protective devices and/or work practice measures. Additional studies should focus on the exposure assessment of other hazards for construction workers, in order to identify high-risk tasks and to improve hazardous work environments.

• Corrosion Science and Technology
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• v.14 no.4
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• pp.177-183
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• 2015

Prestressed Concrete steel Cylinder Pipe (PCCP) is extensively used as seawater pipes for cooling in nuclear power plants. The internal surface of PCCP is exposed to seawater, while the external surface is in direct contact with underground soil. Therefore, materials and strategies that would reduce the corrosion of its cylindrical steel body and external steel wiring need to be employed. To prevent against the failure of PCCP, operators provided a cathodic protection to the pre-stressing wires. The efficiency of cathodic protection is governed by the anodic performance of the system. A mixed metal oxide (MMO) electrode was developed to meet criteria of low over potential and high corrosion resistance. Increasing coating cycles improved the performance of the anode, but cycling should be minimized due to high materials cost. In this work, the effects of $RuCl_3$ concentration on the electrochemical properties and lifespan of MMO anode were evaluated. With increasing concentration of $RuCl_3$, the oxygen evolution potential lowered and polarization resistance were also reduced but demonstrated an increase in passive current density and oxygen evolution current density. To improve the electrochemical properties of the MMO anode, $RuCl_3$ concentration was increased. As a result, the number of required coating cycles were reduced substantially and the MMO anode achieved an excellent lifespan of over 80 years. Thus, we concluded that the relationship between $RuCl_3$ concentration and coating cycles can be summarized as follows: No. of coating cycle = 0.48*[$RuCl_3$ concentration, $M]^{-0.97}$.

• Journal of Energy Engineering
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• v.29 no.2
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• pp.79-84
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• 2020

In order to reduce greenhouse gas by 30% compared to BAU in 2020, research and development of zero-energy building construction technology for reducing greenhouse gas emissions in the construction industry is being conducted. With the recent implementation of the policy as mandatory through the establishment and commercialization of the zero energy building base, the government should devise measures to support and expand technology through the identification of the current status of the zero-energy building incentive system and the erasure of the erasure. In order to implement zero-energy buildings, excessive construction costs are presented as a major issue in revitalizing the supply of new and renewable energy to enhance Passive (energy efficiency grade of 1++) and achieve self sufficiency of energy (20% or higher). In this paper, the major problems and solutions for zero-energy building identification were presented in order to activate the dissemination of zero-energy buildings, and the recent policy changes resulting from the mandatory use of zero-energy buildings were analyzed.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.622-625
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• 2007

Emotional Management refers to the capacity for recognizing our own feelings and those of others, for motivating ourselves, and for managing emotions well in ourselves and in our relationships. Although many of the companies are currently emphasizing that the emotional management is a very important for the management, the study of the emotional management is still extremely passive. This paper is to explain about the reason why emotional management which is becoming an ongoing issue recently should focus less on customers but more on staffs (personnel) in building industries. Furthermore, the paper suggests the required emotional management to the staffs (personnel) with the data from the survey carried out. Finally, this paper is aimed to solve the difficulties that the building industry related would have.

• Journal of the Daesoon Academy of Sciences
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• v.25_2
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• pp.45-70
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• 2015

Master Jeungsan understood a general view of Pungsu but actually he used the theory of Pungsu in his own religious perspective, transcending it. The theory of Pungsu is different. But the fact that it is premised on the principle of 'in and yang', the five-element principle, the Book of Changes, energy thought, and To chugi piyung, etc. is generally recognized. The three important elements of Pungsu are mountain, water, and direction or man. Pungsu has formal principles such as Gallyongbeop, Jangpungbeop, Deuksubeop, Jeonghyeolbeop, Jwahyangbeop, and Hyeongukron. etc. In the late of Joseon, Jeungsan established a new traditional thought, understanding Bibopungsu, Gukdopungsu, Minganpungsu, etc. However, he reinterpreted them to be suitable to his religious ideal and let his followers understand them as well. In particular, Jeungsan overcame the previous view on earth and expressed a new perspective to enhance earth up to the level of heaven. In the perspective of the traditional world, earth is lower than heaven, but Jeungsan made it a status equal to heaven. He mentioned that in the past, the culture and history of man was influenced by earth's energy but today, at the age of man respect, he put passive man influenced by earth-condition on the more subjective and active status. Even though he mentioned different Pungsu, Hyeongguk, and Hyeolmyeong, he expressed the shape of Pungsu within the construction of three worlds, the one of heaven and earth transcending good or ill luck or a favorable change in fortune. He practised the expedient of Pungsu from the stand of the construction of heaven and earth instead of the usage of Bibopungsu, Gukdopungsu, and Minganpungsu. He diagnosed that the division of the world is caused by the one of earth and tried to solve it. Moreover, he said that Myeongdang(a propitious site) must be the man-orientation rather than the earth-orientation. It means that Pungsu, stressing the energy of earth and turning one's luck, is changing into the world of man-orientation. In other words, Jeungsan diagnosed the world of Pungsu but he ultimately used Pungsu theory in building up his own view of religious world transcending such a theory.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.83-88
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• 2023

According to the Ministry of Employment and Labor's industrial accident death statistics, the number of accident deaths in the construction industry increased by 30 people year-on-year to 458, with 77.3% of the accident deaths aged 50 or older and 41.9% aged 60 or older. This study conducted and analyzed a survey to identify safety education, protective equipment, and safety consciousness for 68 elderly workers working at construction sites. As a result, the necessity of diversifying safety education using visual data was confirmed to reconsider the contradictory safety consciousness of elderly workers. It also confirmed the need to improve protective equipment, such as providing protective equipment suitable for individual bodies and periodic replacement, for workers who are passive in wearing protective equipment despite the high need for protective equipment.

• Journal of Energy Engineering
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• v.23 no.1
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• pp.40-45
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• 2014

The ventilation frequency of 0.5 times in residential facilities is applied mandatorily to the housing facilities containing more than 100 house units to improve the indoor air quality and create comfortable interior conditions and pleasantness for residents. The Building Energy Efficiency Rating system requires the implementation of leakage test based on ventilation frequency with the test results being reflected in the efficiency ratings, thereby stimulating the precise construction of the fittings in the periphery of windows and savings of energy that can be lost due to the infiltration air. The inspection results of the Building Energy Efficiency Rating at the site showed that the ventilation frequency was in the range between 0.63 and 0.71 and that the difference was found to have a significant effect on the amount of energy reduction. It is urgent to conduct the study on highly leakage-proof buildings and construction methods, along with the expansion of mandatory leakage-proof diagnosis of non-residential buildings, considering the mandatory ventilation frequency below 0.6 for passive houses under the European standards and the target set by Korea to introduce the passive house, the rigorous standard for energy efficiency in buildings and mitigating their ecological footprint, by 2017 and achieve the zero house by 2025.

• Journal of the Korean GEO-environmental Society
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• v.7 no.4
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• pp.53-62
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• 2006

Recently, the lateral displacement of the passive piles which are installed under the revetment on the soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of ground when the revetment loading exceeds a certain limit. The lateral displacement of ground causes an excessive deformation of underground structure itself and develops lateral earth pressure against the pile foundation. The subject of study is to investigate the lateral displacement of pile foundation during the construction of container terminal at the ${\bigcirc}{\bigcirc}{\bigcirc}{\bigcirc}$ port in Incheon. The displacement of pile and the vertical settlement were measured in the field and finite element method(FEM) analysis for each construction sequence was performed using AFFIMEX(Ver 3.4). From the comparison of the results from field measurement and the finite element analysis, the settlement of the reventment has already occurred at the time of field measurements. Since then, the noticeable lateral displacement of piles and settlement were occurred during the filling of dredged soil inside the revetment dredging and reclaiming work. After completing filling, the lateral displacement and field settlement were reduced remarkably. Generally, the results from the finite element analysis show larger than those from the measurement.

• Journal of Ecology and Environment
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• v.45 no.3
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• pp.105-116
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• 2021

Background: The creation of the National Institute of Ecology began as a national alternative project to preserve mudflats instead of constructing the industrial complexes by reclamation, and achieve regional development. On the other hand, at the national level, the research institute for ecology was needed to cope with the worsening conditions for maintaining biodiversity due to accelerated climate change such as global warming and increased demand for development. In order to meet these needs, the National Institute of Ecology has the following objectives: (1) carries out studies for ecosystem change due to climate change and biodiversity conservation, (2) performs ecological education to the public through exhibition of various ecosystem models, and (3) promotes regional development through the ecological industry. Furthermore, to achieve these objectives, the National Institute of Ecology thoroughly followed the basic principles of ecology, especially restoration ecology, in the process of its construction. We introduce the principles and cases of ecological restoration applied in the process. Results: We minimized the impact on the ecosystem in order to harmonize with the surrounding environment in all the processes of construction. We pursued passive restoration following the principle of ecological restoration as a process of assisting the recovery of an ecosystem degraded for all the space except in land where artificial facilities were introduced. Reference information was applied thoroughly in the process of active restoration to create biome around the world, Korean peninsula forests, and wetland ecosystems. In order to realize true restoration, we pursued the ecological restoration in a landscape level as the follows. We moved the local road 6 and high-voltage power lines to underground to ensure ecological connectivity within the National Institute of Ecology campus. To enhance ecological diversity, we introduced perch poles and islands as well as floating leaved, emerged, wetland, and riparian plants in wetlands and mantle communities around the forests of the Korean Peninsula in the terrestrial ecosystem. Furthermore, in order to make the public aware of the importance of the intact nature, the low-lying landscape elements, which have disappeared due to excessive land use in most areas of Korea, was created by imitating demilitarized zone (DMZ) landscape that has these landscape elements. Conclusions: The National Institute of Ecology was created in an eco-friendly way by thoroughly reflecting the principles of ecology to suit its status and thus the impact on the existing ecosystem was minimized. This concept was also designed to be reflected in the process of operation. The results have become real, and a result of analysis on carbon budget analysis is approaching the carbon neutrality.