• Korean System Dynamics Review
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• v.10 no.1
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• pp.33-60
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• 2009

This study explores the limitation in making a causal model through an existing case and proposes an alternative plan to improve a theoretical system of causation modeling. To make a dynamic and actual model, several principles are needed such as reality based analysis of system structures and dynamics, consistent expression of causations, conversion of numerical formulas to causal relations, classification and arrangement of variables by size of concept, etc. However, it is hard to find cases to apply these considerations from existing models in System Dynamics. Therefore, this study verifies errors of derived models from literatures and proposes principles and guides that should be considered to make a sound dynamic model on a causal map. It contributes to making an opportunity for exciting public opinion to improve theory about causal maps, yet it has limitation that the study does not advance forward to the experimental step. For future study, it plans to make up by classifying and leveling causal variables, developing a dynamic BSC model.

• Journal of Korean Neurosurgical Society
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• v.59 no.1
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• pp.1-5
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• 2016

Chronic subdural hematomas (CSHs) are generally regarded to be a traumatic lesion. It was regarded as a stroke in 17th century, an inflammatory disease in 19th century. From 20th century, it became a traumatic lesion. CSH frequently occur after a trauma, however, it cannot occur when there is no enough subdural space even after a severe head injury. CSH may occur without trauma, when there is sufficient subdural space. The author tried to investigate trends in the causation of CSH. By a review of literature, the author suggested a different view on the causation of CSH. CSH usually originated from either a subdural hygroma or an acute subdural hematoma. Development of CSH starts from the separation of the dural border cell (DBC) layer, which induces proliferation of DBCs with production of neomembrane. Capillaries will follow along the neomembrane. Hemorrhage would occur into the subdural fluid either by tearing of bridge veins or repeated microhemorrhage from the neomembrane. That is the mechanism of hematoma enlargement. Trauma or bleeding tendency may precipitate development of CSH, however, it cannot lead CSH, if there is no sufficient subdural space. The key determinant for development of CSH is a sufficient subdural space, in other words, brain atrophy. The most common and universal cause of brain atrophy is the aging. Modifying Virchow's description, CSH is sometimes traumatic, but most often caused by degeneration of the brain. Now, it is reasonable that degeneration of brain might play pivotal role in development of CSH in the aged persons.

• Journal of the Ergonomics Society of Korea
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• v.30 no.1
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• pp.137-150
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• 2011

Nationally and internationally reported statistics on marine accidents show that 80% or more of all marine accidents are caused fully or in part by human error. According to the statistics of marine accident causes from Korean Maritime Safety Tribunal(KMST), operating errors are implicated in 78.7% of all marine accidents that occurred from 2002 to 2006. In the case of the collision accidents, about 95% of all collision accidents are caused by operating errors, and those human error related collision accidents are mostly caused by failure of maintaining proper lookout and breach of the regulations for preventing collision. One way of reducing the probability of occurrence of the human error related marine accidents effectively is by investigating and understanding the role of the human elements in accident causation. In this paper, causal factors/root causes classification systems for marine accident investigation were reviewed and some typical human error analysis methods used in shipping industry were described in detail. This paper also proposed a human error analysis method that contains a cognitive process model, a human error analysis technique(Maritime HFACS) and a marine accident causal chains, and then its application to the actual marine accident was provided as a case study in order to demonstrate the framework of the method.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.51-117
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• 2019

On 15th November 2017, the coastal city of Pohang, located in the Southeastern part of South Korea was shaken by a magnitude 5.4 earthquake. The earthquake displaced more than 1,700 residents and caused more than $ 300 million dollars of economic loss. It was the second most damaging earthquake in the history of Korea. Soon after the earthquake, a group of scientists raised a possible link between the first Enhanced Geothermal System (EGS) project and the earthquake. At the same time, another group of scientists put forward a different hypothesis of the causation of the earthquake claiming that it was caused by the geological movements that were initiated by the Great Tohoku Earthquake in 2011. Since then, there were scientific debates between the two different groups of scientists. The scientific debate on the causation of the earthquake has been concluded temporarily by the Research Investigatory Committee on the Pohang Earthquake in 2019. The research committee concluded that the earthquake was caused by the Pohang EGS system: this means that the earthquake can be defined not as a natural earthquake, but as an artificially triggered earthquake. This article is to examine the Pohang earthquake can be defined as an Anthropocenic event. The newly suggested concept, the Anthropocene is a relatively novel term to classify the earthly strata and their relationship to geological time. The current geological period should be defined by human activities and man-made earthly environment. Although the term is basically related to geological classification, the Anthropocene has been widely debated amongst humanist and social science scholars. The current disastrous situation of our planet also implies with the Anthropocene. This paper is to discuss how to understand anthropogenic events. In particular, the paper pays attention to two different scholarly positions on the Anthropocene: Isabelle Stenger's Gaia theory and Barbara Herrnstein Smith's relativist theory. The former focuses on the earthly inevitable catastrophe of Anthropocene while the latter suggests to situate and contextualise anthropogenic events. On the basis of the theoretical positions, the article is to analyse how the Pohang earthquake can be located and situated.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.109-118
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• 2017

The key word (KW) is a set of words to clearly express the important causations of marine accidents; they are determined by a judge in a Korean maritime safety tribunal. The selection of KW currently has two main issues: one is maintaining consistency due to the different subjective opinion of each judge, and the second is the large number of KW currently in use. To overcome the issues, the systematic framework used to construct KW's needs to be optimized with a minimal number of KW's being derived from a set of Common Words (CW). The purpose of this study is to identify a set of CW to develop the systematic KW construction frame. To fulfill the purpose, the word reduction method to find minimum number of CW is proposed using P areto distribution function and Pareto index. A total of 2,642 KW were compiled and 56 baseline CW were identified in the data sets. These CW, along with their frequency of use across all KW, are reported. Through the word reduction experiments, an average reduction rate of 58.5% was obtained. The estimated CW according to the reduction rates was verified using the Pareto chart. Through this analysis, the development of a systematic KW construction frame is expected to be possible.

• Journal of the Korean Geographical Society
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• v.41 no.6 s.117
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• pp.701-713
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• 2006

This study considers the case when a district with a high development possibility is set up as a regulation region. Initial assumption is that there would be regulation resistance in and around the regulation region. Pyeongchang is taken as a study areas, performing necessary analysis of environment regulation and regulation resistance based upon spatial analysis with the use of GIS. The research proceeding steps are as follows. After examining Pyeongchang present environment regulation state, environment regulation map is constructed, and classification of Pyeongchang's relatively development possibility level map is made. Using this regulation map and development possibility level map, relative regulation resistance level is measured. The results that the rates of Pyeongchang environment regulation region in its present state was higher than Namhan river basin's regulation region rates. Also, overlapping a high development possibility level region with an environment regulation region, the analysis results give reasons to expect high level of regulation resistance in Doam-myeon and Jinbu-myeon in small town units. The analysis of Pyeongchang new buildings locations with regard to environment regulation showed intensive distribution in the regulation region with high development possibility level and adjacent areas (about 66% of new buildings are distributed within 500m range from regulation region). Such results show that the local administration and existing environment regulation policy, not capable of offering direct benefit to the population, are having immanent problems in environment sustainable development and connected with it environment harm causation.