• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.4
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• pp.1-10
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• 2011

This study investigates the performance of composite (steel-concrete) frame structures through numerical experiments on individual connections. The innovative aspects of this research are in the use of connections between steel beams and concrete-filled tube (CFT)columns that utilize a combination of low-carbon steel and shape memory alloy (SMA) components. In these new connections, the intent is to utilize the recentering provided by super-elastic shape memory alloy tension bars to reduce building damage and residual drift after a major earthquake. The low-carbon steel components provide excellent energy dissipation. The analysis and design of these structures is complicated because the connections cannot be modeled as being simply pins or full fixity ones they are partial restraint (PR). A refined finite element (FE) model with sophisticated three dimensional (3D) solid elements was developed to conduct numerical experiments on PR-CFT joints to obtain the global behavior of the connection. Based on behavioral information obtained from these FE tests, simplified connection models were formulated by using joint elements with spring components. The behavior of entire frames under cyclic loads was conducted and compared with the monotonic behavior obtained from the 3D FE simulations. Good agreement was found between the simple and sophisticated models, verifying the robustness of the approach.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.1
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• pp.59-65
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• 2005

This paper proposes a novel TSK fuzzy modeling algorithm. Various approaches to fuzzy modeling when noise or outliers exist in the data have been presented but they are approaches to degrade effects of outliers or large noise by using loss function in the cost function mainly. The proposed algorithm is the modified version of noise clustering algorithm, and it adopts the method that does not use loss function, but method to cluster noise in a class. Noise clustering is a prototype-based clustering algorithm and it has no capability to regress. It conducts clustering of data first, and then conducts fuzzy regression. There are many algorithms to obtain parameters of premise and consequent part simultaneously, but they need to adapt the parameters obtained for more accurate approximation. In this paper, fuzzy regression is conducted with clustering by modifying noise clustering algorithm. We propose the algorithm that parameters of the premise part and the consequent part are obtained simultaneously, and the parameters obtained are not needed to adapt. We verify the proposed algorithm through simple examples and evaluate the test results compared with existing algorithms. The proposed algorithm shows robust performance against noise and it is easy to implement.

• Korean Journal of Childcare and Education
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• v.9 no.2
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• pp.23-46
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• 2013

The purpose of this study was to obtain basic information for novice teachers' adjustment. The data from five novice teachers were collected by in-depth interviews of each subject, as well as reviewing a memo diary, journal and class diary. The results indicated that the novice teachers' experiences were categorized into difficulties in social relationships, heavy workload, stress related to making mistakes, obtaining support and assistance, adequate understanding of their field of work and so on. The model theory for their process of adjustment was found by grounded theory approach. The causal conditions include mistakes in performance of work and immaturity of managing social relationships. The contexts include age of the children, work conditions(i.e. time and space), amount of workload, unfamiliarity of new work assignments, personalities of colleagues, and high frequency of meeting parents of children. The intervening conditions are composed of a guidance program for novice teachers, support from colleagues, work rewards, and the personalities of novice teachers. The novice teacher use three strategies: trying to ignore, sharing difficulties and accessing support from friends or family, as well as willful efforts to transfer negative emotions into positive ones. The consequences of the strategies include: successful career progression, survival, and desire for leaving the field of work.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.37 no.1
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• pp.1-10
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• 2000

In this paper, a new digital watermarking algorithm using wavelet transform is proposed. Wavelet transform is widely used for image processing, because of its multiresolution characteristic which conforms to the principles of the human visual system(HVS). It is also very efficient for localizing images in the spatial and frequency domain. Since wavelet coefficients can be characterized by the gaussian distribution, the proposed algorithm uses a gaussian distributed random vector as the watermark in order to achieve invisibility and robustness. After the original image is transformed using DWT(Discrete Wavelet Transform), the coefficients of all subbands including LL subband are utilized to equally embed the watermark to the whole image. To select perceptually significant coefficients for each subband, we use level-adaptive thresholding. The watermark is embedded to the selected coeffocoents, using different scale factors according to the wavelet characteristics. In the process of watermark detection, the similarity between the original watermark and the extracted watermark is calculated by using vector projection method. We analyze the performance of the proposed algorithm, compared with other transform-domain watermarking methods. The experimental results tested on various images show that the proposed watermark is less visible to human eyes and more robust to image compressions, image processings, geometric transformations and various noises, than the existing methods.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.3
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• pp.19-29
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• 2011

Until now, many face recognition methods have been proposed, most of them use a 1-dimensional feature vector which is vectorized the input image without feature extraction process or input image itself is used as a feature matrix. It is known that the face recognition methods using raw image yield deteriorated performance in databases whose have severe illumination changes. In this paper, we propose a face recognition method using local statistics of gradients and correlations which are good for illumination changes. BDIP (block difference of inverse probabilities) is chosen as a local statistics of gradients and two types of BVLC (block variation of local correlation coefficients) is chosen as local statistics of correlations. When a input image enters the system, it extracts the BDIP, BVLC1 and BVLC2 feature images, fuses them, obtaining feature matrix by $(2D)^2$ PCA transformation, and classifies it with training feature matrix by nearest classifier. From experiment results of four face databases, FERET, Weizmann, Yale B, Yale, we can see that the proposed method is more reliable than other six methods in lighting and facial expression.

• Child Health Nursing Research
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• v.20 no.4
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• pp.322-331
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• 2014

Purpose: The purpose of this study was to identify health literacy levels of elementary school students. Methods: Participants were 331 fifth and sixth graders in nine elementary schools located in Gyeongsangnam-do. Instruments were 42 health-related words derived from fifth-grade textbook 'Health in Daily Life' for linguistic health literacy, modified Korean Health Literacy Assessment Tool (KHLAT) for numeracy section of functional health literacy, items from a snack box and newspaper article for reading comprehension section of functional health literacy. Data were collected from July 15 to August 15, 2013. Results: The mean score for linguistic health literacy was $24.02{\pm}7.16$ of 42 (57.2% were correct answers). The mean score for functional health literacy was $9.27{\pm}2.30$ of 12 (77.3% were correct answers). There were significant differences in health literacy by grade and academic performance. Conclusion: This study results show that both linguistic and functional health literacy among elementary school students were not high enough to use health-related information and make appropriate health-related decisions. Therefore, it is important to develop strategies aimed at increasing health literacy levels, especially focused on underperforming students. It is also necessary that studies be done on the factors affecting the health literacy of elementary-school students.

• The Journal of Korean Academic Society of Nursing Education
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• v.6 no.1
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• pp.7-22
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• 2000

The purpose of this study was to identified the level of the exposure to the PC Pornography and what's their post-exposure reactions to the PC pornography. The subjects were 423 middle school boys in Pusan. The survey was executed from July 12 through October 30, 1999. The collected data were analyzed by SPSS WIN using the %, mean, ANOVA. The results of this study were as follows: 1. 79.4%(336 boys) were exposed to the PC pornography. 46.3%(196 boys) answered that they experienced the published pornography prior to the PC pornography. 2. 78.5%(333 boys) answered that they had their PC in their homes. This ratio revealed the higher level of possession. 67.6% said that their PC were set in their own rooms. 57.9% of the subject answered they experienced the Internet Communications. 68.6% of the subject said that they tried PC communications once or twice in a week. 38.5% of the subject expressed that they used their own PC for 1-2 hours in a day. Most of them(82.7%) enjoyed the PC games or entertainment programs. 81.3% of the subject answered that their school performance didn't show the progress after the use of their own PC. 78.3% of the subject answered that they acquired information. 45.2% of the subject answered that they made their friend through the Internet communications. 78.7% of the subject answered that the time of family dialogue decreased. 70.7% of the subject answered that the time of their TV watching decreased. 3. As for their post-exposure reactions the subject who were exposed to the PC Pornography showed the point 2.93 in the item 'pleasure'. The point of 'sexual impulses' was 2.81. But the point of 'anxiety' was 2.75, the point of 'dislike or disgust' was 2.62, the point of 'guilty' was 2.59. 4. According to the frequency, the motivation and the companionship on the exposure to PC Pornography, their post-exposure reaction scores showed differences significantly. Finally, the post-exposure reaction had relation to the frequency, the motivation, the companionship and the place (F=3.28 ~ 8.40, p=.012 ~ .000).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.106-115
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• 2003

Diverse multimedia services will be deployed at hand on 3G-and-beyond multi-service CDMA systems in order to satisfy different quality of service (QoS) according to traffic types. In order to use appropriate resources efficiently the call admission control (CAC) as a major resource control mechanism needs to be used to take care of efficient utilization of limited resources. In this paper, we propose a QoS-aware CAC (QCAC) that is enabled to provide service fairness and service differentiation in accordance with priority order and that applies the different thresholds in received power considering different QoS requirements such as different bit error rates (BER) when adopting total received power as the ceil load estimation. The proposed QCAC calculates the different thresholds of the different traffic types based on different required BER applies it for admission policy, and can get service fairness and differentiation in terms of call dropping probability as a main performance metric. The QCAC is aware of the QoS requirement per traffic type and allows admission discrimination according to traffic types in order to minimize the probability of QoS violation. Also the CAC needs to consider the resource allocation schemes such as complete sharing (CS), complete partitioning (CP), and priority sharing(PS) in order to provide fairness and service differentiation among traffic types. Among them, PS is closely related with the proposed QCAC having differently calculated threshold per each traffic type according to traffic priority orders.

• Journal of the Korea Convergence Society
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• v.9 no.6
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• pp.175-182
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• 2018

In this study, the theoretical method and the finite element analysis were designed in parallel to fabricate basic research data on the production of tool horn for cutting machine with ultrasonic vibration energy. In order to perform high-performance ultrasonic cutting, it is necessary to vibrate only with longitudinal vibration instead of transverse vibration. In order to efficiently transmit the mechanical vibration energy, the maximum amplitude should be generated at the output portion. Therefore, the tool horn must be designed so that the excitation frequency of the oscillator and the natural frequency of the tool horn are the same. In order to design the resonance of the tool horn, there are a theoretical approach using the one-dimensional wave equation and a method of reflecting the finite element analysis result to the design model. In this study, the approximate dimensions of the tool horn are first determined through the one- Based on the results of the finite element analysis, the optimal model was selected and reflected in the final shape of the tool horn. We will use this information as the basic data of actual tool horn for cutting, and will compare the production and experimental data with the contents of this research.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.4
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• pp.53-63
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• 2008

Reader collision may occur when neighboring RFID readers use the same channel at the same time. Especially when the readers are operated in dense mode, even though many channels are available, because of frequent reader collisions we can not guarantee the performance of RFID readers. Conventional solutions such as FH(Frequency Hopping) or LBT(Listen Before Talk) are not effective in this situation because they can not schedule RFID readers effectively when RFID readers are operated in multi-channel, dense reader mode, In this paper, we propose a new RFID reader anti-collision algorithm which employs LBT, random backoff before channel access, and probabilistic channel hopping at the same time. While LBT and Random backoff before channel access reduces collisions between competing readers, probabilistic channel hopping increases channel utilization by adaptively changing the hopping probability by reflecting the reader density and utilization. Simulation results shows that our algorithm outperforms conventional methods.