• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.6
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• pp.1129-1138
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• 2014

CAPTCHA is a technique which distinguishes human and machine using what human can judge easily but machine can't. Though Text-based-CAPTCHA has been widely used and can be implemented easily, it is less security than other CAPTCHAs such as image-based, or audio-based CAPTCHAs. To enhance the security of text-based CAPTCHA, many techniques have been developed. One of them is making CAPTCHA recognized hard using complex background or noise. In this paper, we introduce how to apply convolution filtering effectively to attack CAPTCHA and actually analyze Naver's CAPTCHA which has been used for joining a cafe with this method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.357-360
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• 2011

On the matter in line with NCW(Network Centric Warfare) and information age, the military is on an efficient-expanding trend as sharing with status and information promptly through the various and complex exchange of messages and the phone communication between operators, using a highly efficient operating console. The recording devices that record an operational situation to plan a new operation through the mission analysis and result reviews after finishing military operation or training are developed and operated. Recording method is classified into two groups. one is the recording of display shots, another is the recording of an exchange of messages. This study proposes the new data-oriented recording method to reduce the readiness time of replay and the improvement scheme.

• Journal of the Korean Institute of Educational Facilities
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• v.9 no.3
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• pp.23-34
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• 2002

This paper is to analyse the major impact of the new era of information technology on the changes being made in physical environment of existing corporate training centers through the case of on- and off-line LG academies. By the analysis, some interesting features are to be found which can be a hint for the future planning and design of corporate training centers. Unlike the expectation in the early stage of changes, the rapid growth of on-line education forms a very strong partnership with the existing in-house training programs at all levels. Understanding of such key issues surrounding the use of facilities is specific to the formation of an effective environment for training programmes. After all aspects of the facility uses-not just the class rooms, but also the residential, dining, recreational, and support areas, as well as on-line type of educational services-are carefully examined, a design guideline is identified as considerations for guestrooms, classrooms, public facilities, the recreational areas, and the audio-visual provisions.

• Journal of Broadcast Engineering
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• v.6 no.3
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• pp.215-224
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• 2001

In recent days, research activities on multimedia services mainly focus on the multiplexing system with timing synchromization for media components, such as video, audio and text. The MPEG-4 standard emphasizes object-based coding which includes analysis and understanding of the Image content. Since in MPEG-4 we can define objects and encode them independently, we can manipulate and display each object for different applications. This feature of MPEG-4 is also vero useful for multimedia services, such as video streaming cia different network channels, digital versatile disc, internet TV, video E-mail, and so on. In this Paper, we implement a multimedia streaming system which is compliant with the MPEG-4 system and the MP4 file format.

• The KIPS Transactions:PartC
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• v.12C no.2 s.98
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• pp.217-222
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• 2005

The IEEE 802.11 based wireless local area networks are candidates to lead the broadband connectivity in the home and office scenarios. Recently IEEE proposed the 802.11e as a new standard to provide appropriate Quality of Services to a plethora of emerging real-time multimedia and high demanding applications such as high definition movie and audio distribution, video-conference and voice over IP. This paper studies the IEEE 802.11e/IEEE 802.11b interactions focusing on potential unfairness problems that might appear in networks with heterogeneous wireless LAN technologies as well as in the IEEE 802.11e deployment phase.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.5
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• pp.95-102
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• 2008

Typical household loads have nonlinear loads including a personal computer, video, refrigerator, microwave oven, TV, and audio set. These nonlinear loads generate harmonic currents and create distortions on the sinusoidal voltage of the power system. Harmonic field measurements have shown that the harmonic contents of a waveform varies with time. A cumulative probablistic approach is the most commonly used method to solve time varying harmonics. This paper provides in depth analysis on harmonics field measurement of the typical household loads for one year period and the survey is conducted with the objectives to identify the trends of harmonic distortion level present and indentify the future trends of metering in the presence of nonsinusoidal current and voltage waveforms in the system.

• Journal of Korean Critical Care Nursing
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• v.14 no.3
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• pp.1-13
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• 2021

Purpose : This study aims to provide basic data for effective nursing interventions and improvement of nurses' work by exploring their work experiences in single-room-structured intensive care units (ICU) through focus group interviews. Methods : Data were collected through two focus group discussions conducted from March to November 2020 with 13 ICU nurses. Interviews were audio-recorded and analyzed thematically by investigators. Results : Through content analysis, 15 sub-categories and 6 categories were formed. Two themes, "positive experiences patients care in an independent space" and "difficulties in nursing work according to space separation of patients" emerged. There are positive aspects of single-room-structured ICUs, but it was found that practicing nurses had difficulties and required specialized nursing competencies. Therefore, efforts to reduce the burden of nurses in single-room-structured ICUs are necessary. Conclusion : The limitation of this study is that it was conducted in a single hospital because single-room-structured intensive care units are uncommon in Korea. However, this study is of great significance as a basis for establishing guidelines on the efforts required from nurses, hospitals, and governments single-room-structured ICUs in the future.

• Journal of Korean Academy of Rural Health Nursing
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• v.13 no.2
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• pp.25-41
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• 2018

Purpose: In this study undergraduate nursing students' experiences of learning in community health nursing clinical placements was explored on order to develop a more effective practice teaching method. Methods: Focus group interviews (FGI) were held with 11 nursing students in junior or senior year. The interviews were audio-taped semi-structured interviews and were analyzed using content analysis. Results: Nursing students felt that the education system for practice was incomplete in considering the nursing that was needed for their on-site practice. Also they were aware of the totality of the community and voluntarily tried to provide for the expansion of knowledge. Conclusion: Findings indicate a need to establish a cooperative plan between nursing schools and practice agencies and collaborative development in the community health nursing practice guidelines.

• Journal of Korea Game Society
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• v.19 no.2
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• pp.135-144
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• 2019

This study examined the role of enjoyment in the relationship between perceived auditory feedback (PAF), which provides information about the situation during game play, and user experience factors. 100 undergraduates played a mobile game, 'Classy Royale' and took a survey about their user experience. As a result of analyzing the available data from 98 participants, PROCESS MACRO showed that PAF was positively associated with enjoyment, immersion, and intention to use; enjoyment mediated the effects of PAF on immersion and intention. These results can help game research and development regarding the functional value of audio factors.

• The Journal of Information Systems
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• v.30 no.3
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• pp.1-20
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• 2021

Purpose Live streaming commerce refers to the fact that people receive live audio and live video directly over the net. While some e-retailers use Live Streaming as a marketing strategy, the impact of live streaming commerce on customers' reuse intentions is unknown. The purpose of this study is to discuss the impact of live streaming commerce by external environmental factors based on S-O-R theory. Design/methodology/approach In this study, we developed a research model based on the S-O-R theory. Using the questionnaire survey method, consumers who used live streaming commerce on Taobao.com were taken as research subjects. Our research model aims to find out how content attributes, real-time interactions, media characteristics, and situational characteristics as stimulus factors influence consumers' perceptions and thus reuse intentions. Findings The results of the analysis show that external environmental factors have a significant impact on consumer perceptions and that perceived risks and flows can influence consumers' reuse intentions. In addition, we also examined the impact of reuse intentions on consumers' active participation. These results show that live streaming commerce can influence consumer perceptions and behavior in several ways.