• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.163.2-163.2
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• 2012

다목적실용위성 3호는 2012년 5월 발사되어, 위성 기능점검을 위한 시험을 성공적으로 완료하였다. 위성이 발사체로부터 분리된 이후 임무궤도(고도 685km, 승교점 지방시 13시 30분을 갖는 태양동기궤도)를 획득하기 위해서는 궤도조정이 필요하다. 본 논문에서는 다목적실용위성 3호의 초기운영 기간 동안 수행한 총 10번의 궤도조정 계획 및 결과에 대해 기술하였다. 궤도조정 1 단계에서는 궤도조정 절차 및 기능을 점검하기 위해 6번의 시험 궤도조정을 순차적으로 수행하였고 이후 2 단계에서는 임무궤도 진입을 위해 4번의 궤도조정을 실시하였다. 궤도조정을 위해서는 원하는 추력분사 방향을 맞추기 위해 롤 방향 또는 피치 방향의 자세제어가 필요한데, 추력기를 사용하여 자세를 기동하는 모드(Del-V Mode)와 휠을 사용하여 자세를 기동하는 모드(Fine Del-V Mode)로 구분된다. 시험 궤도조정에서는 우선적으로 두 가지 모드에 대한 모드전환 시험을 실시하여 위성체 및 지상국 운영절차에 대한 이상 유무를 점검하였고, 이후 추력기 분사량을 10초로 설정하여 예측 대비 실제 궤도변경 결과값을 확인하였다. 시험 궤도조정의 결과를 토대로 본 궤도조정에서는 임무궤도를 획득하기 위한 경사각 조정 및 고도 조정을 수행하였다. 경사각 조정 시에는 승교점 지방시의 변화량을 줄이고, 이후 자연 교란력에 의한 궤도변화를 고려하여 목표궤도를 계획하였다. 또한, 고도 조정 단계에서는 연료 사용량 및 이심률 변화를 최소화 할 수 있도록 전형적인 호만 궤도천이 방식을 적용하였다. 궤도조정 결과 당초 목표한 값을 정확하게 달성하였고, 궤도조정 이후 궤도변화도 장기간 동안 임무궤도 범위를 유지함을 확인할 수 있었다.

• The KIPS Transactions:PartD
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• v.16D no.1
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• pp.133-138
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• 2009

This paper introduces a pilot CDMA network-based wireless lap time measurement system set up on a ski slope of Yongpyong Ski Resort. The wireless lap time measurement system is one output of U-Sports Project of Gangwon Province, which is intendended for promoting local strategic business and preparation for hosting 2018 Winter Olympic Games at Pyeongchang. A pair of laser sensors is installed at the entry and exit points of a section requiring lap time measurement on a ski slope. Each laser sensor is connected to a sensor node via wire so that the sensor node can detect the time when a skier enters or exits the section. Also each sensor node is connected to a CDMA network via a modem and receives a standard time from a NTP server. Each node executes the NTP algorithm to synchronize its local time to the received server time. As a result of the time synchronization, the sensor nodes maintain its local time within a resolution of at least 10 miliseconds and transmit the time of detection to a central control center. While the wireless lap time measurement system introduced in the paper does not need expensive measurement equipment, the system allows the central control center to provide lap time records in a more convenient manner compared to conventional manual lap time measuremnt methods.

• Proceedings of the KAIS Fall Conference
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• 2001.05a
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• pp.62-65
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• 2001

1997년과 1998년 4월 1일자의 M&A제한규정이었던 증권거래법 제200조의 철폐와 적대적 M&A의 전면허용 그리고 외국자본의 투자제한의 간소화 등 규제완화조치와, 향후 외국인에 대해서 100%까지 주식을 매입할 수 있는 적대적 M&A가 허용될 것으로 보여 우리나라에서도 M&A활동이 보다 본격화 될 것으로 전망되고 있다. 우리나라에서는 1980년대부터 M&A에 대한 관심과 연구가 시작되면서 지금까지 기업합병ㆍ인수의 동기와 효과에 대해서 많은 연구가 이루어져 왔다. 지금까지의 연구내용은 대부분 기업의 M&A동기는 시너지효과를 얻기 위함이며, 또한 공시정보가 합병공시일 전후동안에 주가수익율에 반영되어 합병 당사기업의 주주의 부에 영향을 미치는지의 주가변화 유무에 국한된 것이었다. 또한 1985년부터 1991년 초 사이에 이루어졌던 연구는 당시 국내 M&A 환경이 매우 열악하고 극히 제한된 비정상적인 자본시장 상황 하에서 이루어진 사례에 의한 연구이었기 때문에 연구결과의 문제점과 한계성이 있었고, 실효성 측면에서도 다소 미흡하였다고 할 수 있다. 우리나라 M&A의 성장발전과정을 크게 2단계로 분류한다면, 제1단계는 1975년부터 시작하여 1990년까지로써 이 기간동안의 M&A환경은 그 여건조성과 성숙준비단계였으며, 제2단계인 1990년 초부터 비로소 선진국형 시장경제원리에 근거한 보다 경쟁적이고 자율적인 M&A 시장구조가 형성되면서 활성화 단계로 진입하였다고 볼 수 있을 것이다. 본 연구의 주된 목적은 1990년부터 1996년 사이에 이루어진 상장기업의 M&A 사례를 표본으로 하여 한국에서의 기업합병과 기업인수(주식취득)가 기업가치에 미치는 영향을 구명하는데 있다. 이를 위하여 먼저, M&A 당사기업의 합병성과 발생과 차이 유무를 주가수익율을 측정하여 실증분석하고 다음으로 M&A에 따른 시너지의 잠재적 원천이 어디에 있는지 재무성과분석을 통해서 이를 실증하는데 목적이 있다.PA-designated retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143 kg in 1997 to 0.978 kg in 2000. Targeting a 10% recycling rate for municipal waste in 2001. EPA plans to research and develop new recycling techniques, expand the scope of producer responsibilities, and strengthen existing mu

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.1-9
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• 2016

Railroad bridges account for 25% of the entire high-speed rail network. Railway bridges are subject to gradual structural degradation or fatigue accumulation due to consistent and repeating excitation by fast moving trains. Wireless sensing technology has opened up a new avenue for bridge health monitoring owing to its low-cost, high fidelity, and multiple sensing capability. On the other hand, measuring the transient response during train passage is quite challenging that the current wireless sensor system cannot be applied due to the intrinsic time delay of the sensor network. Therefore, this paper presents a framework for monitoring such transient responses with wireless sensing systems using 1) real-time excessive vibration monitoring through ultra-low-power MEMS accelerometers, and 2) post-event time synchronization scheme. The ultra-low power accelerometer continuously monitors the vibration and trigger network when excessive vibrations are detected. The entire network of wireless smart sensors starts sensing through triggering and the post-event time synchronization is conducted to compensate for the time error on the measured responses. The results of this study highlight the potential of detecting the impact load and triggering the entire network, as well as the effectiveness of the post-event time synchronized scheme for compensating for the time error. A numerical and experimental study was carried out to validate the proposed sensing hardware and time synchronization method.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.97-104
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• 2019

With the development and spread of smart devices, the proportion of mobile shopping is gradually increasing, and the market for mobile gift certificates is also increasing. This study examines the usage status and acceptance attitude of mobile gift certificates for university students who are major customers of mobile gift certificates. Also, based on the extended integrated technology acceptance model (UTAUT2), the results of the analysis of the mediating effect of the intention of the user on the relationship between acceptance of mobile vouchers and recommendation intention were presented. As a result of the analysis, it was shown that the effort expectation, hedonic motivation, price utility, and habit had significant influence on the intention to use the mobile gift certificates. Also, the intention to use mobile gift certificates has mediating effects between effort expectation, hedonic motivation, price utility and recommendation intention. The results of this study can be applied to strategic marketing such as recruitment of new customers through mobile gift certificates while explaining customers' acceptance of technology to mobile gift vouchers or future prospective customers.

• Journal of Popular Narrative
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• v.26 no.1
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• pp.77-102
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• 2020

This article analyzes 'book traveler' stories as a new sub-genre of Korean fantasy web fiction. Formal innovation is revealed as the major motivation of Korean fantasy web fiction's narratives. Furthermore, the imagination of social resistance was presented as the formal devices of the genre. These theses were performed during the analysis of the two characteristics of the genre. In this genre, the main character is the writer or reader of fantasy stories. He moves into a novel he is describing or reading. The original novel, which was entered by the main character, is a space characterized by the custom of a typical fantasy genre. Therefore, the main character actually experiences cliché, typical genre devices and plots. The most important action for the main character here is to 'bend' the custom of the original. Therefore, this genre is in the form of the main motive being the refraction of typology. Meanwhile, the main character is not the central character of the original, but a secondary figure. The central character of the original book is usually from the ruling class, which monopolizes the good resources of society. At this time, the genre creates a subversive situation in which the social underdog goes beyond the social power through plots that overwhelm the central figure. It converts the reader's social desire into a genre device. To summarize, the latest trend in Korean web novel fantasy has captured scenes of renewed Korean genre literature practices. It sensitively reflects the social context of the contemporaries and the reader's desire. Thus, the Korean web novel fantasy has reflected both its internal conditions and its social context.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.4
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• pp.595-606
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• 2022

Korea has the characteristics of traditional power system such as large-scale power generation and large-scale power transmission systems, including 20 GW large-scale power generation complexes in several regions with unit generator capacity exceeding 1.4 GW, 2-3 ultra-high-voltage transmission lines that transport power from large-scale power generation complexes, and 6 ultra-high-voltage transmission lines that transport power from non-metropolitan areas to the metropolitan area. Due to the characteristics of the power system, the penetration level for renewable energy is low, but due to frequency stability issue, some generators are reducing the output of generators. In the future, the issue of maintaining the stability of the power system is expected to emerge as the most important issue in accordance with the policy of expanding renewable energy. When non-inertial inverter-based renewable energy, such as solar and wind power, surges rapidly, the means to improve the power system stability in an independent system is to install a natural inertial resource synchronous condenser (SC) and a virtual inertial resource BESS in the system. In this study, we analyzed the effect of renewable energy on power system stability and the BESS effect to maintain the minimum frequency through a power system simulation. It was confirmed that the BESS effect according to the power generation constraint capacity reached a maximum of 122.81 %.

• Journal of Nutrition and Health
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• v.55 no.4
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• pp.492-505
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• 2022

Purpose: This study was undertaken to examine the perception of Korean consumers regarding soybean meat. Using the Dietary Identify Questionnaire (DIQ), the data obtained were analyzed to identify various factors related to a plant-based diet. Methods: A consumer survey was conducted from June 1^st to 30^th, 2021, targeting 260 Korean consumers over the age of 20 years. Subjects were asked to answer six questions related to the perception of soybean meat. Of the 52 items present in the DIQ, 33 items were verified and reconstructed. All data were analyzed using the SPSS statistics (ver.25). Results: The subjects were divided into two groups, 'passive consuming group' and 'active consuming group', based on their perception of soybean meat. Demographic analysis according to the perception of soybean meat showed significant differences in age, marital status, academic background, and family members. The DIQ was categorized into 7 types: prosocial motivation, out-group regard, centrality, public regard, personal motivation, strictness, and private regard. Comparing by perception about soybean meat, significant differences were obtained between both groups for 'prosocial motivation (p < 0.01)', 'centrality (p < 0.01)', 'private norm (p < 0.05)', and 'personal motivation (p < 0.001)'. The 'passive consuming group' showed relatively low scores in all 4 factors. Conclusion: In the future, the results of this study can be applied to define the meaning of vegan in Korea. We believe our results will provide basic marketing data for the plant-based meat market. This will help expand the soybean meat market for a sustainable life for consumers, which is based on various needs such as health and the environment.

• Journal of Venture Innovation
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• v.6 no.4
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• pp.83-97
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• 2023

The growth of the live commerce market allows you to conveniently and simply start live commerce anytime, anywhere with a smartphone. The use of smartphone services provides continuous communication and is used while feeling psychological attachment, and it leads to psychological attachment, self-consistency with consumers themselves, and self-identity. This study focuses on the motives and perceptions of consumers using live commerce. In other words, we will examine the relationship with service attachment through the moderating effect of self-efficacy and control focus tendency as consumers' personal and psychological characteristics. In other words, the tendency of regulatory focus, which determines the direction of behavior of consumers according to their motives and goals, affects the service attachment of live commerce. We believe that self-efficacy, which is personal confidence and belief that you can plan and execute on your own for the desired outcome in a given situation or task, will control this relationship. As a result of this research, consumers who highly perceive prevention focus were more likely to avoid negative consequences and pursue safety and obligations. Their attachment to live commerce services was stronger, offsetting their confidence and self-efficacy. When using live commerce services, the more they perceive that information acquisition is beneficial, the higher their belief, and self-efficacy, so service attachment, which is an emotional experience as well as a cognitive experience, is strongly formed for consumers with a preventive focus to avoid safety-seeking and negative consequences. Through the present research results, we believe that it will be helpful in operating strategies and management for companies and small business owners who want to understand the psychological behavior of consumers in using live commerce services.

• KDI Journal of Economic Policy
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• v.19 no.1
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• pp.105-149
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• 1997

이 논문에서는 남북한 관계를 중심으로 분쟁해소와 협력관계 구축에 있어서 신뢰(信賴)가 할 수 있는 역할(役割)에 대해 검토해 보았다. 이 논문의 모델은 Kreps-Wilson(1982)의 신규진입 게임을 협력관계 구축이라는 새로운 상황에 맞게 변환시킨 순차적 게임모델로서 유한반복(有限反復) 게임구도와 비대칭적(非對稱的) 정보소유(情報所有)를 그 근간으로 한다. 북한이 남한정부가 진보적이라고 믿는 확률을 남한에 대한 '신뢰(信賴)'라고 정의할 때, 신뢰는 크게 나누어 다음과 같은 역할을 한다. 북한이 남한에 대해 작은 규모의 신뢰감만 가지고 있어도 피의자(被疑者)의 딜레마 (Prisoner's Dilemma) 상황을 피할 수 있으며 상당한 기간동안 남북협력관계(南北協力關係)가 지속될 수 있다. 왜냐하면 보수적 성향의 남한정부도 북한이 개혁정책을 추진할 때 대북(對北) 압박정책 대신 포용정책(包容政策)을 통해 얻을 수 있는 수익이 적지 않은 점을 고려하여 상당기간동안 포용정책을 선택할 동기가 있기 때문이다. 하지만 이와 같이 자신의 성향을 은폐하는 위장행동의 가능성이 높은 동안 신뢰(信賴)는 쉽게 증진되지 않는다. 다만 남북한이 협력을 통해 실질적인 수익을 얻을 수 있을 뿐이다. 남북협력관계를 구축하기 위해 남한이 할 수 있는 일은 정책대응에 소요되는 시간을 줄이는 한편, 개혁정책을 통해 북한이 얻을 수 있는 기대수익(期待收益)을 늘리고 남한에 배신당할 경우 입는 피해를 줄여주는 것이다. 특히 장기적인 관점에서 북한의 기대수익을 점진적으로 늘려 '신뢰도(信賴度)가 넘어야 할 문턱'을 낮추는 것이 효과적인 정책이다. 따라서 남북관계를 진전시키기 위해서는 북한의 지속적인 개혁을 조건으로 북한의 기대수익이 점진적으로 증가하는 KEDO식의 장기적 경협사업(經協事業)을 고안하여 추진해야 한다. 이에 반해 인도주의적 명분하에 일과성의 식량지원을 북한에 제공하는 것은 북한의 구조적(構造的) 경제난(經濟難) 해소나 남북관계의 지속적 진전에 별 도움이 안되는 정책이다. 북한은 북한 나름대로 남한을 한번 믿어볼 필요가 있다. 왜냐하면 상대방에 대한 불신(不信)은 결국 협력관계가 유지될 수 있는 기간을 감축시켜 비효율적인 결과를 초래하기 때문이다.