• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.224.2-224.2
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• 2012

지상시험에서 위성 카메라의 규격에 정의된 모든 원격명령과 상태정보 인터페이스를 확인하고 카메라의 기능 시험을 수행해야 한다. 위성 카메라는 많은 원격명령 및 상태정보 인터페이스를 정의하여 사용하므로 수작업으로 이 모든 인터페이스 및 기능을 시험하는 것은 무리가 있다. 따라서 빠르고, 정확하고, 꼼꼼하게 이를 점검하기 위한 시험 소프트웨어가 필요하다. 시험 소프트웨어는 모든 원격 명령을 카메라에 전송하고, 원격상태정보를 수신하여 명령의 동작여부와 카메라의 상태를 확인한다. 소프트웨어는 명령마다 임의로 파라미터를 세팅할 수 있어 정상적인 명령에 대한 카메라의 동작뿐만 아니라, 비정상 명령에 대한 처리 능력까지 살필 수 있다. 또한 시스템의 메모리에 데이터를 업로드 혹은 다운로드할 때는 데이터의 양이 많기 때문에 소프트웨어는 여러 서브 명령으로 나누어 전송하거나 수신하는 것이 필요하다. 메모리 업로드 다운로드를 위해 소프트웨어는 인터페이스 규격에 맞추어 헤더 정보를 생성하고, 데이터 분석을 위해 별도의 기능을 갖는다. 소프트웨어는 비주얼 C++과 네트워크 기반의 데이터소켓버스를 이용하여 설계하였다. 메인 GUI는 데이터소켓버스를 이용하여 로컬컴퓨터의 서버를 구동하여 카메라를 제어하고 영상데이터를 수신한다. 소프트웨어는 유저가 운용하기 쉽고, 모든 명령과 상태정보 인터페이스를 빠짐없이 점검하기 위해 기능별로 분류하였으며 명령과 연관된 상태정보를 함께 체크할 수 있도록 하였다. 또한 시험시 카메라의 상태를 확인하기 위하여 전원상태, 온도, 기본 상태정보를 항상 모니터링하는 기능을 추가적으로 갖는다.

• Journal of Korea Multimedia Society
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• v.15 no.5
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• pp.651-663
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• 2012

Networked digital signage downloads necessary multimedia contents from a large-sized storage on WAN to its local disk of a limited size before starting their playback. If the required time to download the entire contents gets longer, a start time to play the contents at the digital signage could be delayed. In this paper, we propose a hybrid storage architecture that not only inserts an iSCSI storage layer between the existing local disk and the WAN storage, but offers a contents caching scheme in order to obtain all the necessary contents in digital signage rapidly. The proposed caching scheme determines how to place the downloaded contents both in the local disk and the iSCSI storage. Uniquely, the proposed caching scheme manages the iSCSI storage space by dividing it into two regions: (1) in one region, the digital signage can play the contents directly without downloading them into the local disk; (2) in the other region, the digital signage cannot. Performance evaluations on a simulator and an actual system with workloads of various contents show that a contents-downloading time of the hybrid storage architecture is at maximum three times shorter than that of the existing storage architecture.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.32-42
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• 2013

As the smartphone market grows, the needs for its new business model are also increased. However, most previous researches on smartphone applications focused on Technology Acceptance Model(TAM) and Rogers' Diffusion of Innovation Theory so that there was lack of researches on characteristics for actual smartphone users. In this research, we divided the smartphone applications into five category functions (Call & Text/Music & Video/Information Search/Game/Social Network Service (SNS)). We analyzed characteristic differences of users who used the each application category and found that the differences were statistically significant in both demographic and smartphone usage characteristics (frequency of downloading applications, and download experience of paid applications). Additionally, the smartphone usage characteristic is closely related to the usage duration. The representative result is that the characteristics of people used Music & Video function actively were women in their 20s who downloaded applications more than three times per week, and had a download experience of paid applications. It is positive result for players in the application markets, because it means the users are willing to pay for downloading the paid applications. However, large companies already occupied most of the market share in music applications so that small and medium-sized players should develop an innovative and distinguishable business model in order to success. We believe this research result would provide significant implications for the players in planning the successful business model and developing an user-specific application product.

• Information Systems Review
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• v.18 no.1
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• pp.125-140
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• 2016

Mobile applications (apps) play a significant role in the proliferation of smartphones. According to statistics from Apple, 100 million apps were downloaded in 2008. Since then, the number of cumulative app downloads have increased exponentially. By October 2014, 85 billion apps had been downloaded worldwide. Many studies have attempted to determine the factors that drive app downloads. However, unlike previous studies, we examine the effects of app updates on app rankings. To achieve this goal, we collected data on rankings (gross rankings and category rankings), update contents, reviewer ratings, and number of reviews on apps listed in the App Store. We then categorized app updates into functionality, reliability, and convenience updates following the buying hierarchy model. We found that functionality updates had a positive effect on app gross ranking whereas reliability updates had a positive effect on category ranking. Our study is the first to explore the effects of update content on app ranking. Moreover, our study provides a practical implication for mobile app developers, who should consider app updates in their product development strategy.

• The Journal of the Korea Contents Association
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• v.11 no.9
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• pp.254-266
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• 2011

Wired and mobile Internet has led to increase in online broadcasting content market size. In particular, the fast-growing smart devices like smart phone and tablet PC in mobile Internet market has accelerated the growth of online broadcasting content service market. Meanwhile, the illegal distribution of online broadcasting content has been widespread in this market. There are also significant transaction costs, search costs, contracting and coordination costs in online broadcasting content market. MCP(Master content provider) which is a content distributor has been playing a critical role in preventing illegal content distribution, reducing costs and removing inefficiencies of online broadcasting content market. Thus, the purpose of this study is to investigate the competency of MCP to streamline the online broadcasting contents market from the resource- based view. And this study conducted a case study to explain the status of online broadcasting content market and define what kinds of problems and issues are there in the market in a systematic way. The case study also showed how MCP competency plays an important role in reducing administrative and transaction costs and in solving illegal content distribution and other inefficiencies of the online broadcasting contents market.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.167-175
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• 2011

Increased numbers of Chinese are using the Internet as communications technology develops, and more Chinese are downloading and watching Korean dramas and movies. According to a survey conducted to assess the present state of Korean wave in China, most Chinese young people are watching Korean dramas by downloading them from the Internet. The objective of this study is to see the characteristics of Korean dramas preferred by Chinese viewers: the factors are years of production, diffusers(Broadcasters), types of drama, story topics, main actors, and directors. As a result, Chinese viewers tend to prefer to dramas recently diffused in Korea, miniseries, and comic dramas and romance. Otherwise, broadcasters, main actors, and directors do not influence directly on the choice of dramas of Chinese. Particularly, Korean wave stars in China do not always appear into the dramas favored by Chinese viewers.

• Journal of Korea Multimedia Society
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• v.10 no.5
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• pp.604-611
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• 2007

Java Card has gained genera1 acceptance with standard for smart card and (U)SIM technology, and it is in distinction from native card by its post-issuance of an application and independence from hardware platforms. However, a main weak point of Java Card is its low execution speed caused by the hardware limitation and Java programming language itself. In this paper, we propose a new Java Card Installer to improve the download speed during the post-issuance of an application by resolving symbolic references to physical references in HAM. Our Resolution_In_RAM is based on the improved new RAM writing is 100,000 times faster than EEPROM writing and PageBuffer that is operated as block mode, rather than cell mode is used to write to EEPROM. Consequently, the total number of EEPROM writing are reduced 37%, and the times of downloading are reduced over 30% by using the Resolution_In_RAM-based Java Card Installer.

• Design Convergence Study
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• v.14 no.2
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• pp.151-168
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• 2015

As the market of music download stores moved into the mobile epoch the market was growing explosively. Recently, the digital music market tends to move from the mp3 download market to streaming service and the users can use the service on their mobile devices without reference to any inconvenient download and limited storage capacity. It was found that they mainly use the recommendation music playlist, instant player, main player and sharing of the functions of the streaming service from the user behavior research. This is noticeable features that set apart from the mp3 download service. However, the interface design of the streaming app followed the previous service and it needs the optimization of its UI design. In this study, the usability of high ranked three mobile streaming apps was evaluated. The result of the test was that Naver music and Bugs had high scores overall in four sections of the streaming service features. On the other hand, the Melon had primarily high score in color application on the service. The aim of this study is to suggest the direction of the UI design of music streaming service through the understanding of essence of streaming service and evaluation the usability test.

• Digital Contents
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• no.2 s.141
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• pp.81-81
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• 2005

• TTA Journal
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• s.126
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• pp.83-88
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• 2009