• Title/Summary/Keyword: Event Studies

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Micrometeorological Characteristics in the Atmospheric Boundary Layer in the Seoul Metropolitan Area during High-Event and Non-event Days

  • Park, Il-Soo;Park, Moon-Soo;Lee, Joonsuk;Jang, Yu Woon
    • Journal of Environmental Science International
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    • v.29 no.12
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    • pp.1223-1237
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    • 2020
  • This study focused on comparing the meteorological conditions in the Atmospheric Boundary Layer (ABL) on high-event days and non-event days in the Seoul Metropolitan Area (SMA). We utilized observed PM10 and meteorological variables at the surface as well as at the upper heights. The results showed that high-event days were consistently associated with lower wind speed, whereas wind direction showed no particular difference between high-event and non-event days with frequent westerlies and northwesterlies for both cases. During high-event days, the temperature was much warmer than the monthly normal values with a sharp increasing trend, and Relative Humidity (RH) was higher than the monthly normal, especially on high-event days in February. During high-event days in spring, a double inversion layer was present at surface and upper heights. This indicates that stability in the multi-layer is an important indicator of higher PM10 concentrations. Net radiation in spring and winter is also closely associated with higher PM10 concentrations. Strong net radiation resulted in large sensible heat, which in turn facilitated a deeper mixing height with diluted PM10 concentrations; in contrast, PM10 concentrations were higher when sensible heat in spring and winter was very low. We also confirmed that convective and friction velocity was higher on non-event days than on high-event days, and this was especially obvious in spring and winter. This indicated that thermal turbulence was dominant in spring, whereas in winter, mechanical turbulence was dominant over the SMA.

Business Activity Monitoring Using Process-based Event Analysis (프로세스 기반 이벤트 분석을 이용한 비즈니스 활동 모니터링)

  • Son, Sung-Ho;Jung, Jae-Yoon;Kang, Suk-Ho;Cho, Nam-Wook
    • The Journal of Society for e-Business Studies
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    • v.12 no.2
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    • pp.219-231
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    • 2007
  • Based on a complex event processing technique, an event analysis method for Business Activity Monitoring(BAM) is developed to provide an early warning for on-going events so that process managers effectively detect and monitor potential risks prior to the completion of the events. In this study, process-based event monitoring procedures to extract events with significant risks are presented; Complex event patterns are defined from historical event log data and risks of events are evaluated based on the patterns. A process-based event monitoring architecture for BAM is also presented. The proposed method has been applied to a service process of a home shopping company.

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The Design of an Extended Complex Event Model based on Event Correlation using Aspect Oriented Programming

  • Kum, Deuk-Kyu
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.10
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    • pp.109-119
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    • 2017
  • In recent through development of IOT owing to that mass stream data is being generated in variety of application complex event processing technology is being watched with keen interest as a technology to analyze this kind of real-time continuous data. However, the existing study related with complex event processing only comes to an end at simple event processing based on low-level event or comes to an end at service defect discovery with providing limited operator and so on. Accordingly, there would be limitation to provide useful analysis information. In this paper in consideration of complex event along with aspect-oriented programming an extended complex event model is provided, which is possible to provide more valuable and useful information. Specifically, we extend the model to support hierarchical event structures and let the model recognize point-cuts of aspect-oriented programming as events. We provide the event operators designed to specify the events on instances and handle temporal relations of the instances. It is presented that syntax and semantics of constructs in our event processing language including various and progressive event operators, complex event pattern, etc. In addition, an event context mechanism is proposed to analyze more delicate events. Finally, through application studies application possibility of this study would be shown and merits of this event model would be present through comparison with other event model.

Review on Clinical Studies of Traditional Herbal Medicine and Acupuncture Treatments for Colorectal Cancer Patients (대장암 환자의 한약 및 침치료에 대한 국내외 임상연구 결과에 대한 고찰 - Pubmed를 중심으로)

  • Kang, Yun Hwan;Hong, Mi-na;Han, Chang Woo;Choi, Jun Yong;Park, Seong Ha;Kim, So Yeon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.30 no.4
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    • pp.219-228
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    • 2016
  • The aim of this study was to collect and analyze the clinical studies of traditional herbal medicine and acupuncture treatments for colorectal cancer patients searched in Pubmed and Cochrane library in English. We collected the clinical studies, including randomized controlled trial, case control study and cohort study, in the PubMed and Cochrane library using keywords 'Colorectal Cancer', 'Korean Medicine', 'Traditional Chinese Medicine', 'Kampo' and 'Acupuncture'. Then we analyzed them according to the objective of the therapy, i.e. improving therapy prognosis, reducing chemotherapy's adverse event and reducing operational adverse event. In case RCT, we evaluate the quality of the study with jadad scale. Total 18 studies were selected. There were 3 studies about improving therapy prognosis, 6 studies about reducing chemotherapy's adverse event and 9 studies about reducing operational adverse event. Traditional medicine might improve therapy prognosis in terms of the survival rate, relapse/metastasis rate, quality of life and immune function. The specific herbal formula, 'Goshajinkigan' might not be successful about reducing chemotherapy's adverse event, peripheral neurotoxicity. 'Hangeshanshinto' might reduce the duration of oral mucositis but it is not clear to reduce the incidence of that. 'PHY906' might reduce the incidence of diarrhea. Acupuncture might reduce operational adverse event such as gastrointestinal dysfunction and pain. And 'Daikenchuto' might not be successful in reducing operational adverse event, gastrointestinal dysfunction. Further studies are needed to clarify the efficacy of traditional herbal medicine and acupuncture for colorectal cancer patients.

Co-Event Conflation for Compound Verbs in Korean

  • Jun, Jong-Sup
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.202-209
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    • 2007
  • Compound verbs in Korean show properties of both syntactic phrases and lexical items. Earlier studies of compound verbs have either assumed two homonymous types, i.e. one as a syntactic phrase and the other as a lexical item, or posited some sort of transformation from a syntactic phrase into a lexical item. In this paper, I show empirical and conceptual problems for earlier studies, and present an alternative account in terms of Talmy's (2000) theory of lexicalization. Unlike Talmy who proposed [Path] conflation into [MOVE] for Korean, I suggest several types of [Co-Event] conflation; e.g. [$_{Co-Event}$ Manner] conflation as in kwul-e-kata 'to go by rolling', [$_{Co-Event}$ Concomitance] conflation as in ttal-a-kata 'to follow', [$_{Co-Event}$ Concurrent Result] conflation as in cap-a-kata 'to catch somebody and go', etc. The present proposal not only places Korean compound verbs in a broader picture of cross-linguistic generalizations, but, when viewed from Jackendoff's (1997) productive vs. semi-productive morphology, provides a natural account for classifying the compounds that allow -se intervention from those that do not.

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A Preliminary Study on Event Archives (사건 아카이브의 시론적 연구)

  • Lim, Ji-hoon;Oh, Hyo-jung;Kim, Soojung
    • The Korean Journal of Archival Studies
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    • no.51
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    • pp.175-208
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    • 2017
  • This study aims to establish the definition of "event archive," which collects and manages records that focus on a specific event, in order to present a new perspective onto the collection and management of private records. As such, this study defines "event archive" and then identifies its characteristics by comparing it with community archives and locality archives. An event archive consists of person, spatiality, and temporality. As it puts an emphasis on temporality in particular, this study suggests a spiral model, which grafts person and spatiality onto a time axis. Moreover, this study suggests three considerations for the construction of an event archive. First, it presents different construction methods for different types of event archives depending on the time an event occurred. Second, it suggests records collection and management areas considering the three components of an event archive-person, spatiality, and temporality. Third, it supports a digital archive for an event archive to become an open archive.

The Effects of a Marine Leisure Exhibition Event's Appraisal Attributes on Visitors' Satisfaction and Re-visit Intention

  • Cho, Woo-Jeong
    • Journal of Navigation and Port Research
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    • v.35 no.4
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    • pp.335-342
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    • 2011
  • The purposes of this study were to analyze the effects of a marine leisure exhibition event(MLEE)'s appraisal attributes on visitors' satisfaction and rep-visit intention and thus provide fundamental information that facilitates developing effective marketing and operational strategies for a MLEE. In order to accomplish such purposes, this study employed a survey with a total of 300 visitors to a MLEE hosted by G Province. Questionnaires were developed on the basis of related studies and modified to reflect the study context. Then, such questionnaires were verified to be valid and reliable through content validity, factor analysis and internal consistency analysis. Valid 286 questionnaires were analyzed with correlation analysis and multiple regression analysis on significance level of .05. Following findings were derived from current study. First of all, the appraisal attributes of a MLEE had a significant effect on visitors' satisfaction and among them only the factor of event program had a unique relation with the levels of satisfaction. In addition, the appraisal attributes of the MLEE also had a significant effect on visitors' rep-visit intention behavior and among them event program, transportation and employee factors had unique relations with the performance variable in order. In conclusion, all the research hypotheses that had been set up through previous studies were confirmed in this study.

A Empirical Analysis on the Effect of Seasoned Equity Offering on the Stock's Price (SEO공시 전후의 주가변화에 대한 실증분석)

  • Shin, Yeon-Soo
    • Journal of Industrial Convergence
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    • v.1 no.1
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    • pp.127-142
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    • 2003
  • This Study examines the implications for event studies using the daily stock data. The output present the event study results. The event period is defined from 30 days before through 30 days after the event date, and is broken into four "windows" for abnormal return cumulation: the pre-event period, days -30 through -2; dajys -1 and 0, a period commonly investigated for the immediate impact of the event; and the post-event period, days +1 through +30. It shows how firm's information offerings affect the price process and consequent issues. The Patell Z test is an examples of a standardized abnormal return approach, which estimate a separate standard error for each security-event and assumes cross-sectional independence. The generalized sign test adjusts for the fraction of positive abnormal returns in the estimation period instead of assuming 0.5.

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Object-Oriented Simulation of Container Terminal using a DEVS Formalism (DEVS 형식론을 이용한 컨테이너터미널의 객체지향 시뮬레이션에 관한 연구)

  • 성경빈;정희균;박용욱;이철영
    • Journal of Korean Port Research
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    • v.14 no.1
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    • pp.47-55
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    • 2000
  • In order to cope with the changes of container terminal situation in these days, many simulation studies for container terminal have been accomplished. But previous simulation studies using simulation language have limitations in model representation and difficulties in modeling of large scaled container terminal system. To make these problems better, this paper addresses an object-oriented simulation of container terminal system using a DEVS formalism. The DEVS(Discrete Event System Specification) formalism, developed by Zeigler, supports specification of discrete event system in a hierarchical and modular manner. The formalism provides a mathematical basis for studying discrete event systems with better understood and sounder semantics. In a step of system modeling, a DEVS formalism aims at the exact system modeling that has a basis of semantics and utilizing the object-oriented manner can flexibly cope with the changes of system environment. In this study a model is developed and verified through the simulation of some alternatives.

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A Maximum Entropy-Based Bio-Molecular Event Extraction Model that Considers Event Generation

  • Lee, Hyoung-Gyu;Park, So-Young;Rim, Hae-Chang;Lee, Do-Gil;Chun, Hong-Woo
    • Journal of Information Processing Systems
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    • v.11 no.2
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    • pp.248-265
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    • 2015
  • In this paper, we propose a maximum entropy-based model, which can mathematically explain the bio-molecular event extraction problem. The proposed model generates an event table, which can represent the relationship between an event trigger and its arguments. The complex sentences with distinctive event structures can be also represented by the event table. Previous approaches intuitively designed a pipeline system, which sequentially performs trigger detection and arguments recognition, and thus, did not clearly explain the relationship between identified triggers and arguments. On the other hand, the proposed model generates an event table that can represent triggers, their arguments, and their relationships. The desired events can be easily extracted from the event table. Experimental results show that the proposed model can cover 91.36% of events in the training dataset and that it can achieve a 50.44% recall in the test dataset by using the event table.