• Journal of Elementary Mathematics Education in Korea
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• v.1 no.1
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• pp.53-65
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• 1997

There are many mistakes when we estimate probability of an event, for example, we often omit some likelihoods (of an event), sometimes give too large or too small possibility for a particular case, cannot relate current cases with which were concerned before, apply at another cases as soon as discuss about it insufficiently, etc. If we go into a history of probability and statistics, we shall ascertain that many scientists and mathmaticians made essentially same mistakes with us. In the paper, we will consider the theorization of probability and statistics as a process of modification of mistakes which were made during one's estimating possibility of an event. On that point of view, we shall look at historical background of probability and statistics.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.44.3-45
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• 2015

The 2007 event occurred at 17P/Holmes is known as the most energetic cometary outburst in the history of modern astronomical observations. At this conference, we report our new observation of the comet one orbital period after the event. We thus made the observation of 17P/Holmes in 2014 September using the Kiso Wide Field Camera (KWFC) attached to the 105 cm Schmidt telescope at the Kiso Observatory. It is known that dust particles are thought to converge on the orbital plane of the parent body at the opposite end of the dust ejection viewed from the Sun. Similar phenomenon occurs when dust particles complete one orbital revolution (what we call, neck-line structures). We succeeded in the detection of the dust ejecta of the 2007 outburst by means of the neck-line. With the image, we plan to discuss the ejection velocity and the total mass of the ejecta to deepen our understanding of the historical event.

• Journal of The Korean Astronomical Society
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• v.49 no.6
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• pp.233-238
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• 2016

The missing historical record of the Cassiopeia A (Cas A) supernova (SN) event implies a large extinction to the SN, possibly greater than the interstellar extinction to the current SN remnant. Here we investigate the possibility that the guest star that appeared near Cas A in 1592-1593 in Korean history books could have been an 'impostor' of the Cas A SN, i.e., a luminous transient that appeared to be a SN but did not destroy the progenitor star, with strong mass loss to have provided extra circumstellar extinction. We first review the Korean records and show that a spatial coincidence between the guest star and Cas A cannot be ruled out, as opposed to previous studies. Based on modern astrophysical findings on core-collapse SN, we argue that Cas A could have had an impostor and derive its anticipated properties. It turned out that the Cas A SN impostor must have been bright ($M_V=-14.7{\pm}2.2mag$) and an amount of dust with visual extinction of ${\geq}2.8{\pm}2.2mag$ should have formed in the ejected envelope and/or in a strong wind afterwards. The mass loss needs to have been spherically asymmetric in order to see the light echo from the SN event but not the one from the impostor event.

• (The) Research of the performance art and culture
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• no.18
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• pp.283-314
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• 2009

This paper is an attempt to examine historical drama which change rapidly in the manner of seeing history. Historical records are treated differently unlike in the field of modern history. Now the distinction between historical facts and fictions becomes no longer important. This change is affected by micro history, new cultural history, or post-modern history. History and narrative become interactive each other. In this respect they are no more historical drama. by Han Areum (director Suh Jae-hyung) represents this new trends. Of course, it doesn't suddenly pop up in 2005. It began in by Lee Yoon-Taek, was reinforced in by Kim Tae-Woong, and bloomed in . I intended to search important features of by following three. First is the interest about unimportant persons such as a maid of honor, an eunuch. In , they are the main characters. The author described much about those trivial people revealing the truth in different way of the existence. Second is the way of calling a past. In this piece, the past is not continuous. The past always appears at the stage by the present in the form of split which is imagination, recollection, revival. Third is a mixing genre. Comics, melodrama, and thrillers are all together in . This is a similar phenomenon to historical novel and movie of new trend. Strictly speaking, this piece isn't a history thriller. The accident of lost prince doesn't be treated importantly and the result isn't clear either. In this piece, detective genre is used for a symbol showing that writer pursuits the history, not the event. This represents well the characters of new historical drama because how historical facts are carefully recreated and constructed are important. It's enough to show the possibility to mix genre through comics and melodrama.

• Journal of Korean Society of Transportation
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• v.34 no.2
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• pp.158-167
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• 2016

This study evaluates potential sources of errors in k-NN(k-nearest neighbor) algorithm such as procedures, variables, and input data. Previous research has been thoroughly reviewed for understanding fundamentals of k-NN algorithm that has been widely used for short-term traffic states prediction. The framework of this algorithm commonly includes historical data smoothing, pattern database, similarity measure, k-value, and prediction horizon. The outcomes of this study suggests that: i) historical data smoothing is recommended to reduce random noise of measured traffic data; ii) the historical database should contain traffic state information on both normal and event conditions; and iii) trial and error method can improve the prediction accuracy by better searching for the optimum input time series and k-value. The study results also demonstrates that predicted error increases with the duration of prediction horizon and rapidly changing traffic states.

• Wind and Structures
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• v.31 no.2
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• pp.85-102
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• 2020

Accurate load evaluation is essential in any performance-based design. Design wind speeds and associated wind loads are well defined for synoptic boundary layer winds but not for thunderstorms. The method presented in the current study represents a new approach to obtain design wind speeds associated with thunderstorms and their gust fronts using historical data and Monte Carlo simulations. The method consists of the following steps (i) developing a numerical model for thunderstorm downdrafts (i.e. downbursts) to account for storm translation and outflow dissipation, (ii) utilizing the model to characterize previous events and (iii) extrapolating the limited wind speed data to cover life-span of structures. The numerical model relies on a previously generated CFD wind field, which is validated using six documented thunderstorm events. The model suggests that 10 parameters are required to describe the characteristics of an event. The model is then utilized to analyze wind records obtained at Lubbock Preston Smith International Airport (KLBB) meteorological station to identify the thunderstorm parameters for this location, obtain their probability distributions, and utilized in the Monte Carlo simulation of thunderstorm gust front events for many thousands of years for the purpose of estimating design wind speeds. The analysis suggests a potential underestimation of design wind speeds when neglecting thunderstorm gust fronts, which is common practice in analyzing historical wind records. When compared to the design wind speed for a 700-year MRI in ASCE 7-10 and ASCE 7-16, the estimated wind speeds from the simulation were 10% and 11.5% higher, respectively.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.9-19
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• 2013

In this paper, we develop a Spatio-Temporal graph as of a key component of our knowledge representation Scheme. We design an integrated representation scheme to depict not only present and past but future in parallel with the spaces in an effective and intuitive manner. An event in general occupies not only a space but a time. Hence a crucial premise for the simulation of virtual situations is to position events in the multi-dimensional context, that is, 3-D space extended by the temporal dimension. Furthermore an event tends to have physical, social and mental aspects intertwined. As a result we need diverse information structures and functions to model entities and relations associated with events and to describe situations in different stances or perspectives of the virtual agents. These structures and functions are implemented in terms of integrated and intuitive representation schemes at different levels such as Ontology View, Instance View, ST View, Reality View. The resulting multi-dimensional comprehensive knowledge structure accommodates multi-layered virtual world developing in the time to maximize the diversity of situations in the historical context. The viability of this knowledge representation scheme is demonstrated with a typical scenario applied to a simulator implemented based on the ST Graph. The virtual stage based on the ST graph can be used to provide natural contexts for situated learning or next-generation simulation games.

• Cross-Cultural Studies
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• v.29
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• pp.25-53
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• 2012

The attitude of observer in the painting of history is to exclude a prejudice and a subjective view of an artist and to introduce a photograph, which is a record of objectivity, in the process of painting. Its ultimate intent is to redescribe the fact of an event's image intactly without any prejudice and to represent the event as a proven evidence that it was. The representation of history based on fact had already been conceived in imagination of renowned artists such as Francisco Goya or $Th{\acute{e}}odore$ $G{\acute{e}}ricault$ even before cameras were invented. What they portrayed was their own truth of reality which is gained through their observation, not a history that have corresponded to political ideologies, for all reliance on a limited tool of representation, painting. Furthermore, history was necessary for 19th century impressionism artists to be represented under proven fact in a neutral perspective excluding all subjective prejudice, not based on the representation with imagination. Edouard Manet in particular reconstited an instant moment on the basis of real proof of photograph without personal prejudice or opinion as if today's photojournalism. The catastrophic series by Andy Warhol and the photographic painting by Gerhard Richter show another role of painting in the realm of art, each of them implying information distortion and abuse by current media and intentional deformation toward history as Manet's painting of history. Today, the representation of an historical event that we experience in the era of the Internet and social networks having a great deal of information already came to be the exclusive property of the cutting edge mass media. Nevertheless, the attitude of observer which is realistic and contemplative in the realm of art is the crucial point in terms of artists' act as ever.

• The Korean Journal of Archival Studies
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• no.50
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• pp.231-271
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• 2016

The Donghak Peasant Revolution in 1894 was a nationwide movement from the bottom of the uprising, which opened Korean modernization. Before and after the said revolution, the map of East Asian powers changed. It was an event with very significant meaning. When the revolution occurred in 1894, the peasant revolutionaries could not escape from the yoke of the traitors who rebelled. However, as time passed, recognition of the event also changed. Since the centennial anniversary of the Donghak Peasant Revolution in 1994, concerns and interests regarding the event have increased. Studies on this revolution have also been invigorated, thus shedding new light on the incident. By focusing on the historical sources on the Donghak Peasant Revolution in this article, the current status and archive of the event is studied, its value reviewed, and its collection, classification, arrangement, and description discussed from the perspective of archival studies.

• The Korean Journal of Archival Studies
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• no.32
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• pp.45-78
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• 2012

The significance of Presidential Impeachment in 2004 is subject to interpretations in many different contexts, but its nature as its justice was the constitutional trial by the nation's impeachment system. This study set out to compare and analyze the understanding of the event centered around its nature as "an impeachment event as a public activity" and the records related to it. For that purpose, the study attempted to analyze the impeachment event to understand it as a public activity and examined and analyzed the records of the impeachment event in the public domain through personal visit, phone interview, and request of information disclosure based on the analysis results. An impeachment event as a public activity can be understood as an activity carried out by the National Assembly, which is to issue a motion for impeachment under the norms of the nation's impeachment system, and Constitutional Court, which is responsible for impeachment trial, through their unique rights prescribed in the Constitution. The important subjects of such a public activity included the accused president, the acting presidential system created by the motion for impeachment, and the National Election Commission that provided a decisive ground for impeachment. It was confirmed that the records, which are legal requirements, were well created and have been preserved and managed in the public domain. However, it was difficult to conclude that the records of the impeachment event were thoroughly created in terms of content in relation to affairs as they mainly covered the superficial treatment processes and the results of explicit activities. There was, in particular, the absence of records showing the context of activity.