• 아태비즈니스연구
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• 제9권4호
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• pp.137-155
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• 2018

It has been reported that there is a significant positive relationship between the unexpected earnings on the earnings announcement date and the cumulative abnormal returns following the earnings announcement date. This study investigates whether the results of prior studies are because the public announcement of shareholders' meeting date was selected as the event date instead of either the preliminary earnings disclosure date or the profit/loss change announcement date. The results of this study are as follows. First, post-earnings-announcement drift(PEAD) occurs when unexpected earnings were computed based on the prior period earnings and the public announcement of the shareholders' meeting date as the profit disclosure date. Second, when analyzing the PEAD with the unexpected earnings calculated using the financial analysts' forecasts, no PEAD has been found both on the date of the shareholders' meeting and the earlier date of the preliminary earnings disclosure, profit/loss change announcement, or the public announcement of the shareholders' meeting. Foster et al. (1984) analyze the PEAD using time series model and earnings forecasting model and suggest that the PEAD appears only in the time series model. In this study, too, in the case of using analysts' profit forecasts, the lack of the PEAD shows that the PEAD can be changed according to the method of measuring the unexpected earnings.

• 대기
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• 제27권4호
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• pp.377-384
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• 2017

The effective management of call centers under special circumstances is critical to improve customer satisfaction. In order to effectively respond to call center counseling demand, this paper aims to identify factors having the greatest impact on the number of Korea Meteorological Administration (KMA) call center counseling. To do so, we propose to combine call center data with severe weather announcement data and investigate how the severe weather announcement affects the number of KMA call center counseling. A time lag analysis is conducted and it is found that the severe weather announcement takes about an hour to be reflected in the number of KMA call center counseling. Based on the result of the time lag analysis, we conduct a comparative analysis according to time and season using the data collected from 1 January 2012, to 29 June 2016. The results show that the number of KMA call center counseling increases at lunchtime and decreases during nighttime, and the average rate of change in call center counseling demand tends to be larger under the severe weather announcement. For the comparative analysis according to the season, there are significant differences in the effect of severe weather announcement on the number of KMA call center counseling in spring, fall and winter.

• 한국융합학회논문지
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• 제9권8호
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• pp.53-60
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• 2018

국내 공공전자조달은 국내외에 우수성을 인정받고 있다. 하지만 수요기관이 발주 시 조달업체가 관련 공고를 일일이 확인하거나, 전체 조달공고현황을 한눈에 파악하기에는 어려움이 있다. 그에 따라 본 논문에서는 효과적인 전자조달시스템의 활용을 위해 빅데이터 기술인 HDFS와 아파치 스파크 기술, 협업필터링 기술을 이용하여, 조달공고 추천서비스와 조달공고 계약 트렌드 분석 서비스 구현을 통한 전자조달공고 분석지원 시스템을 개발하였다. 조달공고 추천서비스는 조달업체의 특성과 성격에 맞는 공고를 추천함에 따라 조달업체가 일일이 공고를 검색하는 수고를 덜어 줄 수 있으며, 조달 공고 계약 트렌드 분석 서비스는 조달 공고/계약 정보를 시각화하여 조달업체와 수요기관에게 전자조달의 분석정보를 한눈에 확인할 수 있도록 구현하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.293-296
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• 1998

When the information of announcement facility is modified or added, they are recorded on a tape and then are updated manually using the cassette tape recorder at each office. But the degrade of the tone quality owing to repeated use of the tape and some recording mistakes by processing manually deteriorate the quality of service. And new services such as IN(Intelligent Network) and added functions make the announcement changed very often. Therefore the improved skill of the announcement handling is needed. This paper introduces the implementation of the TDX-10A on-line recording function of transferring voice in PCM data file and storing it in the memory of the recorded announcement facility, when message is recorded onthe fixed type of announcement facility.

• 마케팅과학연구
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• 제16권2호
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• pp.95-108
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• 2006

The major objective of this study is to test if an Olympic Games sponsorship program can influence investors' behavior: stock returns, stock volatility and transaction volumes. The paper deals with stock market reaction on Olympic sponsorship announcement for service organizations using event study method. Our research intention is to test 440 daily stock prices and transaction volumes, in order investigate the potent influence between the announcement of a grand sport sponsorship program and investors' behavior. For this study we examined the announcement data of three grand sponsors of Olympic Games of Athens 2004 (Alpha Bank. Delta and G.T.O) The main contribution of this study is to examine how stock investors' behavior is influenced by the sponsorship program of companies and to extend research scope of marketing field toward stock market. They authors suggest that organizations interested in influencing investors' behavior should invest in sponsorship activities at the sports' sector.

• 대한통합의학회지
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• 제6권3호
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• pp.43-57
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• 2018

Purpose : The act of reporting child abuse by people obliged to report child abuse is a way to detect long-term incidents of child abuse in early stages and to prevent a vicious cycle of social crimes. Thus, this study intends to enhance the reporting of child abuse through a study on the perception of people obliged to report child abuse through the public service announcement on child abuse. Methods : First, in order to identify the demographic characteristics of the subjects, the frequency and percentage were calculated. Second, in order to verify the reliability of the variables, Cronbach ${\alpha}$ was calculated. Third, in order to examine the perception of people obliged to report child abuse and the perception of reporting, a t-test (verification) and One-way ANOVA were conducted. Fourth, in order to identify the relationship between variables, a Correlation analysis was conducted. Result : The results show that people obliged to report child abuse did not perceive the public service announcement on child abuse positively and it varied depending on their jobs. The correlation between the public service announcement on child abuse and sub-factor of perceptions of reporting showed that a positive correlation was found in reliability, interest, understanding, perceiving the public service announcement on child abuse, perceiving severity and effectiveness, whereas a negative correlation was found in perceiving hazards. Conclusion : The education for preventing child abuse is required by the job type of people obliged to report. It is necessary to convey the message of effective public service announcement. The public service announcements on child abuse must be nationwide and long-term projects.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권11호
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• pp.4573-4594
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• 2020

Announcement protocol in Internet of Vehicles (IoV) is an intelligent application to enhance public safety, alleviate traffic jams and improve transportation quality. It requires communication between vehicles, roadside units and pedestrian to disseminate safety-related messages. However, as vehicles connected to internet, it makes them accessible globally to a potential adversary. Safety-related application requires a message to be reliable, however it may intrude the privacy of a vehicle. Contrarily, if some misbehaviour emerges, the malicious vehicles must be able to traceable and revoke from the network. This is a contradiction between privacy and accountability since the privacy of a user should be preserved. For a secure communication among intelligent entities, we propose a novel announcement protocol in IoV using group signature. To the best of our knowledge, our work is the first comprehensive construction of an announcement protocol in IoV that deploys group signature. We show that our protocol efficiently solves these conflicting security requirements of message reliability, privacy and accountability using 5G communication channel. The performance analysis and simulation results signify our work achieves performance efficiency in IoV communication.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권5호
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• pp.1450-1470
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• 2023

In a Vehicular Cloud (VC) network, an announcement protocol plays a critical role in promoting safety and efficiency by enabling vehicles to disseminate safety-related messages. The reliability of message exchange is essential for improving traffic safety and road conditions. However, verifying the message authenticity could lead to the potential compromise of vehicle privacy, presenting a significant security challenge in the VC network. In contrast, if any misbehavior occurs, the accountable vehicle must be identifiable and removed from the network to ensure public safety. Addressing this conflict between message reliability and privacy requires a secure protocol that satisfies accountability properties while preserving user privacy. This paper presents a novel announcement protocol for secure communication in VC networks that utilizes group signature to achieve seemingly contradictory goals of reliability, privacy, and accountability. We have developed the first comprehensive announcement protocol for VC using group signature, which has been shown to improve the performance efficiency and feasibility of the VC network through performance analysis and simulation results.

• 한국ITS학회 논문지
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• 제9권3호
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• pp.1-11
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• 2010

교통방송에서 제공하는 교통정보는 방송매체의 특성상 정성적인 교통정보 방송멘트를 사용하고 있기 때문에 도로 상에서 정보 이용자가 공감할 수 있는 교통정보를 제공하기 위해서는 제보자와 정보 제공자의 판단 기준을 이용자 측면에서 명확하게 정립할 필요가 있다. 이에 본 연구에서는 교통방송에서 명확한 구분 없이 임의적으로 사용되고 있는 교통정보 방송멘트에 대한 기준을 제안하고자 통신원, 교통방송 종사자, 운전자들이 동일하게 느끼는 교통상황 판단 기준과 교통정보 방송멘트에 대한 인지특성을 조사하고 분석하였다. 그 결과, 교통상황별로 인지 차이가 거의 없는 평균 통행속도를 기준으로 한 정보 제공이 이루어져야 하며, 통행속도를 기준으로 한 교통상황은 원활 상태가 60km/h 이상, 서행 상태가 40~60km/h 미만, 정체 상태가 40km/h 미만으로 분류됨을 알 수 있었다. 그리고 35개의 교통정보 방송멘트를 교통상황별로 분류해 본 결과, 원활 상태는 8개, 정체 상태는 9개로 명확하게 분류되었으나 18개 멘트는 애매하게 인지하고 있어 서행 상태를 표현하는데 적절하지 않음을 알 수 있었다. 따라서 '원활', '서행', '정체'라는 단어를 포함한 멘트를 직접 사용하는 것이 좋을 것으로 판단되었다. 향후 연구과제로는 차량 동적시뮬레이터 등을 통해 실제와 동일한 교통흐름을 재현하고 교통정보 방송멘트를 제공하고 운전자의 인지 반응을 조사하여 보다 명확한 기준을 정립해야겠다.

• 한국화재소방학회논문지
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• 제25권2호
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• pp.101-106
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• 2011

본 연구에서는 예기치 않는 화재 등의 재해가 돌발적으로 발생하였을 경우 소리 정보에 의해서 사람들을 적극적으로 올바른 방향으로 피난 유도시키려면 피난자가 유도 정보의 내용을 알아들을 뿐만 아니라 피난 방향도 지각할 수 있는 것이 필요하다. 이에 피난 유도음의 방향을 감지할 수 있는 선행음 효과를 이용하여 각 건물공간에서 선행음과 후속음에 대해서 음압레벨 변화와 지연시간 변화에 따른 청감실험 결과 즉, 최적의 음성 피난유도음을 도출하였다. 각 실내공간에서 최적의 음성 피난 유도음은 다음과 같다. 1) 강의실 공간에서 음성 피난 유도음의 최적의 조건은 선행음보다 후속음이 지연시간을 10ms~50ms 갖는 경우와 선행음과 후속음의 음압레벨 차이가 없거나 선행음이 높은 경우에 선행음 방향에 대하여 양호하게 인지하였다. 2) 복도 공간에서의 최적의 음성 피난 유도음은 선행음보다 후속음이 지연시간 20~60ms인 경우에 선행음에 대하여 양호하게 인지하였다. 3) 체육관에서는 최적의 음성 피난유도음은 선행음보다 후속음이 지연시간 10~40ms인 경우와 선행음이 후속음보다 음압레벨이 크거나 같은 경우에 선행음에 대하여 양호하게 인지하였다.