• Journal of Korean Academy of Nursing
• /
• v.40 no.2
• /
• pp.182-190
• /
• 2010

Purpose: This study was done to identify self-directed learning readiness, achievement goal orientations, learning satisfaction and learning achievement, and to evaluate the factors affecting learning achievement for nursing students using a web-based Health Assessment e-Book. Methods: The research design was a cross-sectional study with a structured questionnaire and data were collected before using the web-based Health Assessment e-Book and 1 week after finishing. The participants were 80 nursing students who were taking the Health Assessment class from March to June 2009. Results: Mean score for subjective learning achievement was 31.26 and for objective learning achievement, 69.25. Subjective and objective learning achievement were positively correlated with self-directed learning readiness, mastery goal, attitude toward distance education, and learning satisfaction. In subjective learning achievement, learning satisfaction and mastery goal were significant predictive factors and explained 64% of the variance. Objective learning achievement was significantly predicted by learning satisfaction and self-directed learning readiness, which explained 24% of the variance. Conclusion: Learning satisfaction, mastery goal and self-directed learning readiness were found to be very important factors associated with learning achievement for nursing students using a web-based Health Assessment e-Book. To provide high quality and effective web-based courses and to improve nursing students' learning achievement and learning satisfaction, educators should consider the learner's characteristics from the initial stages of lecture planning.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.5
• /
• pp.964-971
• /
• 2003

According to the development of information processing technology and computer hardware, PACS systems have been installed in many hospitals. They can increase the efficiency and the convenience remarkably for handling medical images using digitalized data. After we compare the generation images with other cases, we can read the images correctly and decide how to treat the patients. If the results, included test method and specialist's opinion, are represented dynamically on homepage in hospital. then visitors can get their experience in directly and understand the field of examination and the area of medical treatment. In this thesis, we display the effective images such as MR of the abnormal cases according to parts and diseases, the movie and still images such as Angio image, the other multimedia materials such as the sound and text of doctor's opinions, in SMIL based on XML, concerning the problem of concurrency.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.8C
• /
• pp.793-800
• /
• 2005

Computation of multimedia data increases in portable devices with the advances of the mobile and personal communication services. The energy management of such devices is very important for the battery-powered operation hours. The motion estimation in a video encoder requires huge amount of computation, and hence, consumes the largest portion of the energy consumption. In this paper, we propose a novel architecture that a low energy management scheme can be applied with several fast-search algorithms. The energy-constrained Vdd hopping (ECVH) technique reduces power consumption of the motion estimation by adaptively changing the search algorithm, the operating frequency, and the supply voltage using the remaining slack time within given power-budget. We show that the ECVH can be applied to the architecture, and that the power consumption can be efficiently reduced.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.7
• /
• pp.24-31
• /
• 2009

Resource reservation scheme is an effective method to guarantee QoS for handoff calls in the next generation multimedia mobile communication systems, but it causes negative impacts on blocking probability of new calls. In this paper, to optimize the tradeoff between dropping probability of handoff calls and blocking probability of new calls, relay station based handoff prioritization control algorithm is proposed. In this algorithm, the relay station participates in handoff procedure and enables mobile stations to have guaranteed prompt service after handoff by providing highly efficient data transmission. In this paper, Markov chain models of the proposed handoff prioritization schemes are developed, and dropping probability of handoff packets and blocking probability of new packets are derived. By numerical analysis, the proposed algorithm has been proved to outperform conventional handoff prioritization schemes in terms of dropping probability of handoff packets and blocking Probability of new packets.

• Journal of Korean Elementary Science Education
• /
• v.33 no.4
• /
• pp.795-805
• /
• 2014

In this study, we investigated elementary students' perceptions of digital science textbooks after they used the digital science textbooks based on 2009 national science curriculum. For this study, 103 $3^{rd}$ and $4^{th}$ grade students were participated. They responded to the survey items about use comfortableness and satisfaction of the digital textbook. Descriptive survey and interviews were administered to understand their perceptions of advantages and disadvantages of the digital science textbooks. The analyses of the data show that students' perceptions of the digital science textbooks were positive in general and their satisfaction appeared to be quite high. They perceived the most advantage as having chances to use multimedia like video clips, pictures, and sound. They also mentioned other advantages like viewer functions such as highlights and notes, learning support functions such as supplementary materials and videos for science experiments, and smart pad functions to operate with hands. On the other hand, they pointed out disadvantages that there were many errors and lags in operation. We also discussed the educational implications about improving digital science textbook for effective science learning.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.5
• /
• pp.117-124
• /
• 2004

Various multimedia systems have been developed and their application areas widely proliferate. Thus, the interoperability is getting important among various networks and devices. The video transcoding is a technology to solve this interoperability problem among various coding standards. Transcoding can be defined as the conversion of one compressed coded data to another. In this paper, MPEG-2 to MPEG-4 transcoder in the spatial domain is compared with that in the DCT domain. The transcoder is very useful when a video sequence that is originally encoded for digital TV, DVD or satellite broadcasting is served in mobile environment. In order to compare two transcoders, all modules except motion compensation and down sampling are implemented identically. In addition, both transcoders do not search for motion vector. Instead, the decoded information is reused to the encoder. The experimental results show that the transcoder in the spatial domain is usually better than that in the DCT domain with respect to PSNR (Peak Signal-to-Noise Ratio), bitrate and execution time.

• 전자공학회논문지 IE
• /
• v.43 no.2
• /
• pp.87-92
• /
• 2006

Many watermarking methods for protecting the intellectual property right and authentication multimedia data have been proposed in recent years. In image authentication watermarking, watermark is inserted into an image to detect any malicious alteration. So, watermark for authentication and integrity should be erased easily when the image is changed by scaling or cropping etc. We propose in this paper a fragile watermarking algorithm for image integrity verification and tamper localization proofing using special hierarchical structure. In the proposed method, the image to be watermarked is divided into blocks in a multi-level hierarchy and calculating block digital signatures in thus hierarchy. At each level of the hierarchy, a digital signature for each block is calculated using the seven most significant bit(MSBs)-plane values of all pixels within the block. And the resulting signature is incorporated into the LSBs of selected pixels within the block. We provide experimental results to demonstrate the effectiveness of the proposed method.

• Journal of Broadcast Engineering
• /
• v.16 no.5
• /
• pp.738-749
• /
• 2011

In this paper, we study QoS(Quality of Service) control protocols and the effect using MAC/PHY parameters of client device in mobile network. We proposes the way of controling the bit-rate by estimating the channel condition of the client with measured MAC/PHY parameters which is sent from the client. With the proposed method, more accurate available bit-rate can be estimated compared to conventional protocol, RTCP(Real-time Transport Control Protocol). The accurate bit-rate estimation can decrease wasted bit-rate and transport delay. In the result of the advantages, the transported video quality can be enhanced. In this paper, we show the effects of enhancement using client's the field data measured in WiMAX.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.5
• /
• pp.83-90
• /
• 2012

This paper is a research on the design and implementation of a small real-time radio broadcasting system by using smart phone based on Android. It was designed as the server-client structure, and used the progressive download of HTTP as methods of transferring data to further simplify the system. In order to realize the real-time broadcasting, the original audio source was divided with a short interval and captured to be compressed and stored into files. Then the client receives and plays the compressed files sequentially as it is downloaded. However, this method occurs two problems each of which is the loss of capturing the original source in the server and the discontinuity of playing the files in the client. We solved the problem in the server by separating the thread into two parallel threads of which is each captured and compressed/stored, also by using the double buffering method. The problem in the client was solved using MediaPlayer in Android and the file queue to store the multiple files.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.20 no.2
• /
• pp.209-214
• /
• 2020

The equitable partitioning problem(EPP) is classified as [0/1] binary skill existence or nonexistence and integer skill levels such as [1,2,3,4,5]. There is well-known a polynomial-time optimal solution finding algorithm for binary skill EPP. On the other hand, tabu search a kind of metaheuristic has apply to integer skill level EPP is due to unknown polynomial-time algorithm for it and this problem is NP-hard. This paper suggests heuristic greedy algorithm with polynomial-time to find the optimal solution for integer skill level EPP. This algorithm descending sorts of skill level frequency for each field and decides the lower bound(LB) that more than the number of group, packing for each group bins first, than the students with less than LB allocates to each bin additionally. As a result of experimental data, this algorithm shows performance improvement than the result of tabu search.