• Geomechanics and Engineering
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• v.11 no.4
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• pp.457-469
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• 2016

Steep rock slope with water-filled tension crack will happen to overturn around the toe of the slope under seismic loading. This failure type is completely different from the common toppling failure occurring in anti-dipping layered rock mass slopes with steeply dipping discontinuities. This paper presents an analytical approach to determine the seismic factor of safety against overturning for an intact rock mass slope with water-filled tension crack considering horizontal and vertical seismic coefficients. This solution is a generalized explicit expression and is derived using the moment equilibrium approach. A numerical program based on discontinuous deformation analysis (DDA) is adopted to validate the analytical results. The parametric study is carried out to adequately investigate the effect of horizontal and vertical seismic coefficients on the overall stability against overturning for a saturated rock slope under two water pressure modes. The analytical results show that vertically upward seismic inertia force or/and second water pressure distribution mode will remarkably decrease the slope stability against overturning. Finally, several representative design charts of slopes also are presented for the practical application.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.11
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• pp.877-882
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• 2016

Disaster robots have accepted tele-operation in order to share the intelligence of human operators and robot systems. Virtual wall is one of the tele-operation technology to support recognition of human operator. If the virtual wall can block the robot from dangers, the operator will feel comfortable and can concentrate on fundamental missions. In this paper, we proposes and compares three methods for virtual wall visualization in tele-operation using 3D reconstruction. First is a virtual wall visualized only with edges. A wall filled with transparent color is the second method. Finally, third method is a texture-mapped virtual wall. In the experiments, we discuss their merits and demerits in view of robot tele-operation.

• Fire Science and Engineering
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• v.27 no.2
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• pp.25-30
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• 2013

'Heaundae Woosin Building' fire was the case that a fire breaking out on the $4^{th}$ floor spread out the $38^{th}$ floor which is a top story and the penthouse was destroyed by fire. After this fire, the fire safety for high rise buildings has been on the rise and several new laws and regulations related in the buildings were created. The study is to analyze Heaundae officetel building case using FDS which is one of the CFD programs for fire. The methodology of this study is to analyze the case comparing with fire spread and route from a virtual fire simulation and related articles and a video clip of actual scene fire. This study shows that a fire spreading on top of levels spent approximately 30 minutes and, which is similar to the actual fire case. Also the pattern of spread has similarity with the case. However, even if the actual fire case shows the fire pattern was "V shape", the smoke-view presents the fire dose not spread horizontally as much as the real fire case. The result shows uncertainty of the modeling based on many grids and a limitation of putting interior finish input sources and the direction of the wind might cause the difference. Also, to analyze factors influencing on a vertical fire, another fire modeling is performed by in condition of modeling environment considering concrete interior finish between buildings and no wind. The result presents the fire spread in smoke-view does not spread vertically as much as the actual case.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.989-998
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• 2014

Recently volcanic eruptions and activities occurring in many parts of world have become a common global concern to many countries. The severity of these Volcanic disasters, such as of Mt. Eyjafjallajokull in Iceland and Mt. Merapi in Indonesia, have caused damages and causalities reaching astronomical levels. The infrastructure is categorized into 18sections that appropriately reflecting the survey data collected from various government agents, current inhabitant and engineers to accumulate a database on the priorities and preferences of restoring and reconstructing many kinds of infrastructure and facilities. The survey data was collect by using the "Likert 5 Scale Method" which emphasized the importance and priority of reconstruction and restoration for the specific facilities and infrastructures. The data was corrugated, organized and used in plotting and planning a strategic recovery agenda. The survey results were analyzed and verified to ensure the validity and reliability of the data by using chi-square test. This paper presents that recovery period and recovery cost to the total damage of infrastructure and facilities were used to make a recovery network with implemented construction management method. The research is expected that a more efficient and prompt recovery protocol and recovery plan can be executed and can be use as a reference and database.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.388-391
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• 2008

The Domestic housing Industry has to give consequence to the redevelopment and rebuilding of existing housings rather than the supply by developing a new building site, and now those tendencies are rapidly spreading out. Also, because apartment buildings occupies 50% over of the existing housing, its maintenance, repair, remodeling and reconstruction got to be necessary area for the slumming prevention of a residential area and the disaster prevention occurred by durability lowering of the building. It is increasing the interest for reusing and recycling of C&D waste. The government is doing efforts to diminish amount of C&D waste. But there couldn't find any efforts for developing Integrated system to manage and to estimate lightly generated amounts of C&D waste. So, this study presents a integrated computer system that can estimate easily quantity of C&D waste by using CAD draw and 3D Object.

• The Journal of Korea Robotics Society
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• v.15 no.3
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• pp.293-300
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• 2020

The purpose of our sensor system is to transparentize the large hydraulic manipulators of a six-ton dual arm excavator from the operator camera view. Almost 40% of the camera view is blocked by the manipulators. In other words, the operator loses 40% of visual information which might be useful for many manipulator control scenarios such as clearing debris on a disaster site. The proposed method is based on a 3D reconstruction technology. By overlaying the camera image from front top of the cabin with the point cloud data from RGB-D (red, green, blue and depth) cameras placed at the outer side of each manipulator, the manipulator-free camera image can be obtained. Two additional algorithms are proposed to further enhance the productivity of dual arm excavators. First, a color correction algorithm is proposed to cope with the different color distribution of the RGB and RGB-D sensors used on the system. Also, the edge overlay algorithm is proposed. Although the manipulators often limit the operator's view, the visual feedback of the manipulator's configurations or states may be useful to the operator. Thus, the overlay algorithm is proposed to show the edge of the manipulators on the camera image. The experimental results show that the proposed transparentization algorithm helps the operator get information about the environment and objects around the excavator.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.68-76
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• 2023

Background: In the process of discussion on the possibility of using radionuclide-contaminated soil and debris generated by radiation disasters, a strategy for the proper management of radiation exposure protection while considering the source of the contaminated materials is necessary. Materials and Methods: The radiological protection criteria that are likely to be applied to the source-related approach based on the International Commission on Radiological Protection recommendations and the International Atomic Energy Agency safety standards are summarized. We proposed five interpretations of radiation protection to contribute to the promotion of discussion on the possibility of using a part of low-level-radionuclide-contaminated soil and debris in the post-accident rehabilitation. Interpretations I to III are based on the idea of "using a reference level to protect the public in post-accident rehabilitation," whereas IV and V are based on the idea of "using the dose constraint to protect the public in the post-accident rehabilitation when the sources are handled in a planned activity." The former idea is subdivided into three based on the definition of the source, which is managed by the reference level, and the latter idea is divided into two depending on whether or not additional dose from using contaminated materials is deemed acceptable. Results and Discussion: To confirm the applicability of the five interpretations presented, we suggested the concrete values of protection criteria via two feasible cases. In this case study, we proposed radiation protection by the dose constraint based on the Interpretation IV and chose 1 mSv/yr for the public and 20 mSv/yr for workers dealing with radionuclide-contaminated materials. Conclusion: We concretely and systematically demonstrated how the concept of radiation protection can be applied to the process of discussion on the possibility of using radionuclide-contaminated materials within the framework of an international system of protection. This study's findings can provide necessary information to discuss the possibility of using radionuclide-contaminated materials as an alternative option for recovery and reconstruction after a radiation disaster from the viewpoint of radiation protection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1D
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• pp.73-81
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• 2008

Hereafter, the domestic housing industry has to give consequence to the redevelopment and rebuilding of existing housings rather than the supply by developing a new building site, and now those tendencies are rapidly spreading out. Also, because apartment buildings occupies 50% over of the existing housing, its maintenance, repair, remodeling and reconstruction got to be necessary area for the slumming prevention of a residential area and the disaster prevention occurred by durability lowering of the building. Accordingly, C&D waste is rising largely by reason of demolition works in city is increasing. The right management of C&D waste is being one of very important things, but little research has been conducted to estimate correctly C&D waste. In this study is to suggest standard units of C&D waste which can estimate demolition quantity of apartment. This units can estimate easily and correctly C&D waste in demolition works, also can possible use very important material to carry out policy of national waste management.

• The Journal of Art Theory & Practice
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• no.14
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• pp.7-32
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• 2012

The exhibition was started in 2010 in the New Acropolis Museum of Athens and embarked a journey since 2011 as a travelling exhibition inside Greece and abroad. The main purpose of the exhibition was to draw attention of the general public to the value of the 'rescue excavation' and of cultural heritage of Greece, by presenting the reconstruction bust of a girl whose skull was found in Kerameikos cemetery of ancient Athens. The new Kerameikos excavation was initiated by the construction of Metropolitan Railway lines in the center of Athens between 1992 to 1998. It revealed a pit of a mass burial where about 150 people were inhumed in a very hasty way without proper funeral rites or offerings. These bodies are identified as the victims of the infamous plague of Athens in the first years of the Peloponnesian War(430-426 BC). The epidemic disease killed almost one third of the city population including Pericles, and brought extreme fear and panic to the Athens society. The traditional funerary rites were totally disrupted, and the social decorum and the morality among the citizens became enfeebled. The plague and the civil war were the decisive factors to end the Golden Age of Democratic Athens. However, the exhibition organizers did not focus on the tragic aspect of this disaster and its casualties. Their main concern was to simplify the scholarly works of archaeological excavation and microchemistry analysis so that the exhibition viewers will easily understand and empathize the living value of the scholarly works of ancient Greek civilization. The centripetal element of the exhibition was the vivid face of an 11 years old ancient girl 'Myrtis', which was carefully reconstructed based on both the scientific data and artistic imagination. Also the set up of the exhibition was structured in order to stimuli cognitive and emotional experience of the visitors who witnessed the rebirth of a vibrant human being from an ancient debris. The museologists' continuous efforts to promote projects of contemporary artists, publications, and school programs related to the exhibition indicate that the ulterior motive of this exhibition is the cultural education of the present and future generation through the intimate experiences of ancient Greek life. Also this is the reason why the various museums that held the travelling exhibition try to make the presentation as a gesture of memorial service for an anonymous Athenian girl who deceased circa 2400 years ago. The pragmatic efforts of Greek scholars and museologists through exhibition show us a way to find a solution to the continuous threat of cultural resources by massive construction projects and land development, and to overcome public indifference to the history and cultural heritage.