• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.703-711
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• 2018

Water distribution system (WDS) pipe bursts are caused from excessive pressure, pipe aging, and ground shift from temperature change and earthquake. Prompt detection of and response to the failure event help prevent large-scale service interruption and catastrophic sinkhole generation. To that end, this study proposes a improved Western Electric Company (WECO) method to improve the detection effectiveness and efficiency of the original WECO method. The original WECO method is an univariate Statistical Process Control (SPC) technique used for identifying any non-random patterns in system output data. The improved WECO method multiples a threshold modifier (w) to each threshold of WECO sub-rules in order to control the sensitivity of anomaly detection in a water distribution network of interest. The Austin network was used to demonstrated the proposed method in which normal random and abnormal pipe flow data were generated. The best w value was identified from a sensitivity analysis, and the impact of measurement frequency (dt = 5, 10, 15 min etc.) was also investigated. The proposed method was compared to the original WECO method with respect to detection probability, false alarm rate, and averaged detection time. Finally, this study provides a set of guidelines on the use of the WECO method for real-life WDS pipe burst detection.

• Journal of Navigation and Port Research
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• v.29 no.10 s.106
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• pp.865-870
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• 2005

Because there are only a limited number of means of action that are available for the master to pursue in the event of flooding, onboard decision support system has been required. The majority of systems activated during a flooding emergency (such as watertight and semi-watertight doors, bulkhead valves, dewatering pumps etc.) almost exclusively aim to restore a sufficiently high level of subdivision to prevent flooding from spreading through the ship. Even though assuming the flooding scenario is not catastrophic, the use of ballast tanks can be an additional and very effective tool to ensure both prevention of flooding spreading and also improve ship stability. This paper describes an optimization algorithm devised to choose the set of ballast tanks that should be filled in order to achieve an optimal response to a flooding accident.

• Journal of Advanced Navigation Technology
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• v.21 no.1
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• pp.58-65
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• 2017

Global navigation satellite system (GNSS) has a weakness of signal integrity caused by broadcasting type data transmitting direct to user from navigation satellite. Loss of GNSS signal integrity can make a catastrophic event in the operation of unmanned aerial system (UAS) because position decision is only depended on GNSS. So it is required to apply alternative method to reduce a risk and to guarantee a GNSS signal integrity for UAS operation. This paper addressed the reason of loosing GNSS signal integrity, the effectiveness of signal jamming/spoofing and GNSS application trend for UAS. Also suggested the flight safety enhancing method in case of GNSS signal jamming for UAS as technical and political approaches.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.131-131
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• 2010

The power of semiconductor laser diodes has been limited primarily by the heating effects which occur at high optical intensities. The actual limiting event can take one of a number of forms such as. catastrophic optical damage or filamentation. A general approach to this problem is to design a heterostructure which creates a high powered output while maintaining low internal optical intensities. A graded index separate confinement heterostructure (GRIN-SCH) is one such structure that accomplishes the above task. Here, the active region is sandwiched between graded index layers where the index of refraction increases nearer to the active layer. This structure has been shown to yield a high efficiency due to the confinement of both the optical power and carriers, thereby reducing the optical intensity required to achieve higher powers. The optical confinement also reinforces the optical beam quality against high power effects. Quantum dots have long been a desirable option for laser diodes due to the enhanced optical properties associated with the zeroth dimensionality. In our work, we use PICS3D software created by Crosslight Software Inc. to simulate the performance of In0.67A10.33As/A10.2Ga0.8AsquantumdotsusedwithaGRIN-SCH. The simulation tools are used to optimize the GRIN-SCH structure for high efficiency and optical beam quality.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.75-80
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• 2005

Because there are only a limited number of means of action that are available for the master to pursue in the event of flooding, onboard decision support system has been required The majority of systems activated during a flooding emergency (such as watertight and semi-watertight doors, bulkhead valves, dewatering pumps etc.) almost exclusively aim to restore a sufficiently high level of subdivision to prevent flooding from spreading through the ship. Even though assuming the flooding scenario is not catastrophic, the use of ballast tanks can be an additional and very effective tool to ensure both prevention of flooding spreading and also improve ship stability. This paper describes an optimization algorithm devised to choose the set of ballast tanks that should be filled in order to achieve an optimal response to a flooding accident.

• Journal of Navigation and Port Research
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• v.44 no.3
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• pp.203-210
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• 2020

It is important to establish a strong system of agencies for protection against disasters. Also, the system of protection against disasters by the residents is necessary to be strengthen the system. We examined the roles of the protection agencies and the administrational institutions against disasters. The results are: 1) The mutual assistance agency relies on the administrational institution on a hardware surface., 2) On the software surface some systems of protection from disasters are under the control of the agencies, and some are under the control of the administrational institution., 3) The shelters are unable to meet the needs of people in any disaster. Thus, we should use of the existing institutions as evacuation areas., 4) The people working in the city in which they live tend to know the protocols of the disaster measures and to recognize the disaster maps well.

• Parasites, Hosts and Diseases
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• v.57 no.6
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• pp.587-593
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• 2019

Excavation (2008-2014) carried out under the Uffizi Gallery (Florence, Italy) led to the discovery of 75 individuals, mostly buried in multiple graves. Based on Roman minted coins, the graves were preliminarily dated between the second half of the 4th and the beginning of the 5th centuries CE. Taphonomy showed that this was an emergency burial site associated with a catastrophic event, possibly an epidemic of unknown etiology with high mortality rates. In this perspective, paleoparasitological investigations were performed on 18 individuals exhumed from 9 multiple graves to assess the burden of gastrointestinal parasitism. Five out of eighteen individuals (27.7%) tested positive for ascarid-type remains; these are considered as "decorticated" Ascaris eggs, which have lost their outer mammillated coat. Roundworms (genus Ascaris) commonly infest human populations under dire sanitary conditions. Archaeological and historical evidence indicates that Florentia suffered a period of economic crisis between the end of 4th and the beginning of the 5th centuries CE, and that the aqueduct was severely damaged at the beginning of the 4th century CE, possibly during the siege of the Goths (406 CE). It is more than plausible that the epidemic, possibly coupled with the disruption of the aqueduct, deeply affected the living conditions of these individuals. A 27.7% frequency suggests that ascariasis was widespread in this population. This investigation exemplifies how paleoparasitological information can be retrieved from the analysis of sediments sampled in cemeteries, thus allowing a better assessment of the varying frequency of parasitic infections among ancient populations.

• Journal of English Language & Literature
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• v.58 no.5
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• pp.943-974
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• 2012

This paper aims to suggest the compromising vision of nature and technology as the solution to get out of the globally accelerated technology environment in Don DeLillo's Cosmopolis. This novel intends to emphasize on the importance of physical environment as a precondition for the survival of human. Eric wants to be a posthuman with the cybernetic idea, pursuing to be the digital self in a vast biosphere that integrates both the nature and the technology. His obsessive worship of technology through his quest for the futurity results in the effacement of the humanity and the insulation from the nature. Cosmopolis is DeLillo's first 9/11 novel, which describes a young-billionaire asset manager Eric's one-day life in New York in April 2000. Eric can be the third Twin Tower as a symbol of global economic hegemony. By the allusion of the 9/11 catastrophic event, it can be said that Eric's fall is caused by his hubris and avarice as a global capitalist. Crossing the 47th Street toward the West in his limousine, his journey is revealed as the environmental reflections on his desires to attain the futurity and transcendence by technology. This novel cautions that the abuse of technology can bring out the obsolescence and erasure of the humanity and the nature. DeLillo suggests that the best hope for the evolutionary possibility of posthuman can be realized through the correlation with nature and technology. This future-oriented novel warns that the excessive technology should not lead to the disappearance of community and humanity, and the separation of self and nature. It admonishes that they should not follow pseudo-cosmopolitanism as the greedy world citizens, devoting on the velocity of newest technology. This novel recommends that humans should be the world citizen of global ecosystem, making the ameliorative environment through the correlation with self/environment and technology/nature, and gardening the restorative biosphere and the younger planet.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.339-343
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• 2015

To rapidly recover ceased functionality of a facility after a catastrophic seismic event, critical decisions on facility repair works are made within a limited period of time. However, prolonged damage assessment of facilities, due to massive damage in the surrounding region and the complicated damage judgment procedures, may impede restoration planning. To assist reliable structural damage estimation without a deep knowledge and rapid interactive analysis among facility damage and restoration operations during the approximate restoration project planning phase, we developed a prototype of distributed facility restoration simulations through the use of high-level architecture (HLA) (IEEE 1516). The simulation prototype, in which three different simulations (including a seismic data retrieval technique, a structural response simulator, and a restoration simulation module) interact with each other, enables immediate damage estimation by promptly detecting earthquake intensity and the restoration operation analysis according to estimated damage. By conducting case simulations and experiments, research outcomes provide key insights into post-disaster restoration planning, including the extent to which facility damage varies according to disaster severity, facility location, and structures. Additional insights arise regarding the extent to which different facility damage patterns impact a project's performance, especially when facility damage is hard to estimate by observation. In particular, an understanding of required type and amount of repair activities (e.g., demolition works, structural reinforcement, frame installation, or finishing works) is expected to support project managers in approximate work scheduling or resource procurement plans.

• Cross-Cultural Studies
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• v.43
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• pp.265-288
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• 2016

This essay begins by discussing the issue of the definition of a catastrophe as a trauma by visual media and the problems that result. We assume a concrete approach towards these problems by examining the process through which 9/11 was defined as a "national trauma" in the exclusion of images of bodies falling from towers, which were some of the most shocking images in the media coverage of 9/11. The choice to exclude images of falling men from American visual media representations of 9/11 goes hand in hand with the tendencies of a contemporary trauma theory. This essay assumes that the representations in the U.S visual media depend on "antimimetic theory," one of the leading contemporary trauma theories, in order to validate its logic, and examines the limitations and problems of the theory. This work aims to examine the issue of the definition of a catastrophe as trauma by visual media on the basis on the "antimimetic theory" and the danger that results. Because the antimimetic theory, which the visual media in the United States uses to define 9/11 as trauma, emphasizes literal and unmediated representation of an external event, it lacks an understanding of the human aspects of the event. There is no way to intervene in the construction and interpretation of the trauma. As a result, the theory discourages active attempts to find a solution to the problems of the people directly connected with the event. Thus, it provides an opening for manipulative intervention of an external power. This essay attempts to provide a critical analysis of the "antimimetic theory" in order to help people who witness catastrophic events through various types of visual media, and to seek an alternative means of experiencing and responding to the trauma, that does not stem from the perspective of specific media outlets or external powers.