• ETRI Journal
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• v.32 no.2
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• pp.273-280
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• 2010

The overall channel capacity of a multihop wireless path drops progressively over each hop due to the cascading effect of noise and interference. Hence, without optimal rate adaptation, the video quality is expected to degrade significantly at any client located at a far-edge of an ad-hoc network. To overcome this limitation, decoding and forwarding (DF), which fully decodes codewords at each intermediate node, can be employed to provide the best video quality. However, complexity and memory usage for DF are significantly high. Consequently, we propose syndrome-based partial decoding (SPD). In the SPD framework an intermediate node partially decodes a codeword and relays the packet along with its syndromes if the packet is corrupted. We demonstrate the efficacy of the proposed scheme by simulations using actual 802.11b wireless traces. The trace-driven simulations show that the proposed SPD framework, which reduces the overall processing requirements of intermediate nodes, provides reasonably high goodput when compared to simple forwarding and less complexity and memory requirements when compared to DF.

• Journal of Information Technology Applications and Management
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• v.27 no.3
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• pp.37-54
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• 2020

In response to the recent decline in the school-age population, universities have made attracting foreign students a major policy task for universities. As a result, the number of foreign students increased rapidly in terms of quantity, but in terms of quality, the risk is inevitable. Accordingly, the government presented education and internationalization competency certification system indicators on the basis of which quality control of students was systematized. Based on the above certification system, this study focused on analyzing the multiple factors that are actually given to the academic adaptation (performance) of the 2200 students who entered a certain university. In addition, factors other than the certification system index were discovered to comprehensively track how they affect the academic performance of students studying abroad. The researcher found the multi-reciprocal model analysis showed that the difference between the learner and the moderator was significant, and whether or not they had the Korean proficiency test (TOPIK) was significant. It also said that it could have a direct impact on Chinese University Entrance Exams (高考) are significant. If a model that is very effective in selecting students is established by each university and used as an indicator through this study, it will serve as a basis for efficient selection of students.

• Women's Health Nursing
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• v.1 no.2
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• pp.260-274
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• 1995

In order to help the theory development for "women health", and to apply to the women client care, the concept analysis of "women health" was done. According to the concept analysis method by Walker & Avant, the characters of concept "women health" were analyzed from literature. The results were as followings : first, it emphasizes reproductive focused health care(childbirth-oriented) and normal development process regarded as abnormal. Second, it is affected by cultual environment. Third, it is related with sex. Forth, it considers the human, feminine and maternal aspects. Fifth, it need woman-centered nursing approach to promote woman's quality of life. Sixth, it stresses not only wholistic human health promotion but also the harmony between human and environment. Seventh, it is needed to be considered woman's various experiences as important and it approaches phenomenogically and interdisciplinary. Eighth, it needed to understands person-situation interactional aspect. Ninth, it can promote the adaptation power to surrounding environment. Above results can elucidate the concept of "women health", and will be a basis of theory development of "women health" In practical nursing, these results will be a basis for the promotion of women health and for the increase of life quality.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.1 s.108
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• pp.10-18
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• 2005

The main concept of social carrying capacity is based on the principle that 'there are limits to the number of users a given recreation site can accommodate in order to provide quality of recreation experience'. The quality of the experience is revealed as user's satisfaction and perceived crowding. In this respect, studies of social carrying capacity have been frequently conducted by measuring perceived crowding and satisfaction. The purpose of this study is to identify the variables affecting perceived crowding, and causality bet-ween satisfaction and perceived crowding. Four hundred seventy six visitors were selected at Naejangsan National park on peak day of autumn excursion through on-site survey. The collected data were applied by factor analysis for categorizing the research variables, and multiple regression for finding the causality among variables. The study results are follows. The expectation of crowding, as a normative variable for perceived crowding, are categorized by three factors; circulation, user facility, and landscape. The circulation factor is the most powerful affecting perceived crowding among three factor. The landscape factor, however, do not have statistical significance on perceived crowding. The causality between satisfaction and perceived crowding is found. Although this relation is significant in statistics, magnitude of the coefficient is very small. It might be interpreted that satisfaction cannot be predicted simply from a user's perception of crowding, but a multi-dimensional concept such as adaptation and coping behavior.

• Journal of the Korean Institute of Intelligent Systems
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• v.6 no.2
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• pp.52-56
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• 1996

In trainir~ga back-propagation neural network, the learning speed of the network is greatly affected by its learning rate. Most of off-line fashioned learning-rate selection methods, however, are empirical except for some deterministic methods. It is very tedious and difficult to find a good learning rate using the empirical methods. The deterministic methods cannot guarantee the quality of the quality of the learning rate. This paper proposes a new learning-rate selection method. Our off-line fashioned method selects a good learning rate through stochastically searching process using evolutionary programming. The simulation results show that the learning speed achieved by our method is superior to that of deterministic and empirical methods.

• ETRI Journal
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• v.32 no.1
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• pp.33-43
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• 2010

The increasing demand for non-sinusoidal currents affects the quality of distribution networks. Harmonic detection is a crucial step in the cancellation of those components by active power filters. In this paper, the discrete cosine transform (DCT) is compared with different implementations based on Fourier transforms, demonstrating their equivalences and the advantages provided by the former. We demonstrate that the phase error in the presence of grid frequency deviations and the transient length are reduced by half in comparison to the discrete Fourier transform. A novel algorithm is developed to provide frequency adaptation to the DCT, taking advantage of its good features. The window width is adjusted in real time according to the actual value of the grid fundamental frequency by means of a phase-locked loop. A technique based on dithering is employed to overcome the limitation caused by the truncation of the window number of samples, so the frequency resolution is enhanced. The theoretical approach is verified by simulated and experimental results.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.197-201
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• 2020

Purpose: This study aimed to assess the quality of dental prostheses printed by digital light-processing (DLP) technology. Methods: Ten experimental models were prepared. The ten specimens that were printed by DLP technology constituted the DLP group. The ten specimens that were produced in the same model by the casting method constituted the control group. The marginal gaps of the 20 specimens produced were measured. These gaps were measured by a silicon replica technique at two abutments of the specimen. Therefore, 20 marginal gaps were measured in each group. An independent sample t-test was performed to compare the marginal gaps measured in the two groups (α=0.05). Results: According to the results of the measurement, there was a significant difference between the mean marginal gap of the control group (78.8 ㎛) and that of the DLP group (91.5 ㎛), p<0.001. Conclusion: Although the mean marginal gaps of dental fixed prostheses produced by the DLP method was higher than the mean marginal gap of those produced by the casting method, it was considered to be within the clinical threshold value suggested by some previous studies.

• Management & Information Systems Review
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• v.32 no.3
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• pp.173-188
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• 2013

I guess that e-learning buying behaviors have some selection criteria which are interactivity, contents quality, perceived usefulness, and corporate reputation. And I propose that the effects of selection criteria on adaptation intention are moderated by buyer-user status. To accomplish research purpose, I conducted a field survey with a self-administered questionnaire in both user-buyer and analysed the causal relations among the variables by regression analysis. Findings are these. In all of the customer, interactivity, perceived usefulness, and corporate reputation had positive effects on re-attending intention to another e-learning class. In case of users(students), interactivity, contents quality, and perceived usefulness had positive effects, but buyer(parents) showed both perceived usefulness and corporate reputation had positive effects on re-attending intention.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2003.11a
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• pp.83-86
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• 2003

With the opening of digital broadcast services and development of wire/wireless Internet, the current multimedia broadcasting is provided for has various services. The user will be provided lots of various content through the various channel and media. Content provider and consumer want the various service using content with the better quality which is fit to user preference. For transmitting this content in the limited transmission channel capacity, it needs to transmit the highly compressed content which user wants. The content of 3D mesh model-based on MPEG-4 enables the various content service that provides the lower capacity and the better quality, and Targeting service enables just provide the contents that user more wants and likes. The adaption of Java application program and 3D program can provide the content service utilizing 3D mesh model, so content provider and consumer can share the more information about the content. This paper has presented the study on the targeting service using compression of 3D mesh model-based on MPEG-4 and the adaptation of Java application program using it

• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.163-171
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• 2023

The intelligent transportation system has made a huge leap in the level of human services, which has had a positive impact on the quality of life of users. On the other hand, these services are becoming a new source of risk due to the use of data collected from vehicles, on which intelligent systems rely to create automatic contextual adaptation. Most of the popular privacy protection methods, such as Dummy and obfuscation, cannot be used with many services because of their impact on the accuracy of the service provided itself, they depend on changing the number of vehicles or their physical locations. This research presents a new approach based on the shuffling Nicknames of vehicles. It fully maintains the quality of the service and prevents tracking users permanently, penetrating their privacy, revealing their whereabouts, or discovering additional details about the nature of their behavior and movements. Our approach is based on creating a central Nicknames Pool in the cloud as well as distributed subpools in fog nodes to avoid intelligent delays and overloading of the central architecture. Finally, we will prove by simulation and discussion by examples the superiority of the proposed approach and its ability to adapt to new services and provide an effective level of protection. In the comparison, we will rely on the wellknown privacy criteria: Entropy, Ubiquity, and Performance.