• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.9
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• pp.4180-4196
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• 2017

In this paper, we analyze average capacity of an amplify-and-forward (AF) cooperative communication system model in multi-relay multiuser networks. In contrast to conventional cooperative networks, relays in the considered network have no embedded energy supply. They need to rely on the energy harvested from the signals broadcasted by the source for their cooperative information transmission. Based on this structure, a two-step selection scheme is proposed considering both channel state information (CSI) and battery status of relays. Assuming each relay has infinite or finite energy storage for accumulating the energy, we use the infinite or finite Markov chain to capture the evolution of relay batteries and certain simplified assumptions to reduce computational complexity of the Markov chain analysis. The approximate closed-form expressions for the average capacity of the proposed scheme are derived. All theoretical results are validated by numerical simulations. The impacts of the system parameters, such as relay or user number, energy harvesting threshold and battery size, on the capacity performance are extensively investigated. Results show that although the performance of our scheme is inferior to the optimal joint selection scheme, it is still a practical scheme because its complexity is much lower than that of the optimal scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.4
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• pp.646-652
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• 2015

In this paper, the system-level performance is evaluated for the feedback scheme on the pre-coding matrix index (PMI) and channel quality indication (CQI), which are required for user selection in the multi-user MIMO system. Our analysis demonstrates that the number of users, the number of selected users, and codebook size are the key factors that govern the performance of the best companion grouping (BCG)-based user scheduling. Accordingly, we have confirmed that the probability of forming the co-scheduled user group is determined by these factors, which implies that the number of PMI's and codebook size can be dynamically determined so as to maximize the average system throughput as the number of users varies in the cell.

• The Korean Journal of Health Service Management
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• v.13 no.2
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• pp.39-54
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• 2019

Objectives: This study was performed to investigate selection factors for specialized hospital and to find out the impact of hospital selection factors on satisfaction, revisiting invention and recommendations. Methods: A survey was performed with 398 inpatients of 4 specialized joint hospital in Busan. Data were collected from August to October 2016 with questionnaires and analyzed using SPSS 24.0. Results: First, inpatients know that it was a specialized hospital were highly satisfied and willing to revisit and recommend. Second, in hospital satisfaction, influence size was shown in order of specialty factors, service quality factors, physical factors, and accessibility factors. Third, the intention to revisit hospitals was higher in the awareness of a specialized hospital and high satisfied inpatients, and recommendation intend were affected by the higher revisitation intention, the high satisfaction level, and the high professionality level. Conclusions: All the hospital selection 4 factors for joint specialized hospitals affects satisfaction level which is linked to revisit and recommend. Specialized Hospitals will have to strengthen qualitative management of hospital selection factors to enhance patient satisfaction.

• Human Ecology Research
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• v.55 no.3
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• pp.289-301
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• 2017

This study was to analyze the effects of the career education program for students with disabilities. The analysis was performed based on two research questions. First, the total effect size on the career program for students with disabilities was considered. Second, the difference of the effect size between the sub-groups regarding dependency variables, types of disabilities, types of schools, number of people, and number of sessions was also included for analysis. For this, the author reviewed a database and analyzed 12 previous studies, presented in five master thesis and seven Korean journals from 2005 to 2015 based on the author's selection criteria. Subsequently, 27 effect size was found. The publication bias was analyzed by Rosenthal's fail-safe N. The overall effect size for all studies on the random effect model was 1.717, which was positive and high in value. Given the heterogeneity among the effect size, the subgroup analysis was conducted, and indicated that the effect size was significantly high when the purpose of the program was related to the student's self-decision ability. The results demonstrated that the programs were specified for students with intellectual disabilities, when the schools were elementary, when the number of students in a group was 1-10, and when program sessions lasted more than 21 times, the effect size was high. Implication for the future research and program implication were discussed on these findings.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.2
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• pp.27-36
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• 2018

Purpose: In the case of mass disaster, the establishment of temporary medical facilities for the first aid and treatment is required for the stable accommodation of patients caused by the disaster. However, the criteria for decision making related to the deployment of field emergency medical facilities are not specified. So, The purpose of this study is to draw considerable factors needed for the deployment of field emergency medical facilities and to make proposal for site selection process of field emergency medical facilities on the basis of the factor. Methods: This study performs text mining of disaster-related laws, guidelines and documents to derive key factors affecting site selection, also proposes a decision making process and conducts virtual deployment to validate the process. Results: The key factors for the site selection derived as the size of the damage, the size of the DMAT inputs, the location of available place, and distance to the disaster base hospital. As a result of virtual deployment following proposed decision making process, It is confirmed that the site of field emergency medical facilities is changed depending on the type of disaster, even if the scope of the disaster damage was the same. Implications: The deployment of field emergency medical facilities requires a separate criteria for each type of disaster, not uniform, as a future research a quantitative approach of the criteria needs to be performed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.561-566
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• 2011

In EPCglobal Class-1 Gen-2 RFID system, a slot-count selection algorithm has been proposed to determine the slot-count size depending on the status of reply slot. In the slot-count selection algorithm of Gen-2, the slot-count value is increased or decreased by the weight C, which is identical and independent of the slot status. It has an advantage that the algorithm is simple, but it is difficult to maintain an optimal slot-count size. Therefore, in this paper, we propose an adaptive slot-count selection algorithm, which applies the parameter C differently based on the result of tag replies. Through simulations, it is demonstrated that the collision rate for the proposed scheme is about 42% and 65% lower than the schemes proposed by Wang and Gen-2. Therefore, the adaptive slot-count selection algorithm achieves faster tag identification time compared with the existing algorithms due to the low collision rate.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.3
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• pp.457-463
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• 1996

An esthetically pleasing result in denture service is dependent upon several consideration. Esthetic considerations for the edentulous patient include tooth size, shape, arrangement, positioning, gingival contour, age, sex, personality differences, and ethnic type. Especially, the form of anterior artificial teeth is an important factor on the esthetics. The selection of artificaial teeth requires understanding and knowledge on physical and biologic factors and has to meet the indivisul esthetics and functional needs of each patient. However, the selection of artificial teeth is based on the large degree of subjective judgement of the dentist, Therefore, this is one of the most unscientific processes. Many attempts have been made to find a guideline for the selection of artificial teeth. Temperamental theory by White and Hall utillized with the physical characteristics such as body size, body form, color of eyes and hair, and disposition. SPA theory by Frush and Fisher utilized with the basis of sex, personalities, and age of the indivisual. There has not been provided for a guideline and study on the selection of artificial teeth for Koreans yet. This study was aimed to evaluate the William's typal matching theory in Koreans. 1. The facial forms of korean adult were ovoid(46.3%), square(36.7%) and tapered(17.0%) form. 2. The anatomic forms of natural maxillary incisors were ovoid(45.3%), tapered(31.3%), square(23.3%) form. 3. The forms of face and natural maxillary incisors were ovoid(21.9%), squared(11%), tapered(6.3%). 4. The natural maxillary incisors were similar in form to the facial form only in 39%. There was no correlation between the form of the face and the form of natural maxillary central inisors in Koreans. 5. Artificaial teeth which was selected according to the typal matching theory did not represent the form of the natural teeth in 61 per cents of the fatal, but it felt that they harmonized with the form of the patient's face and produced good results.

• MALSORI
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• no.52
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• pp.111-120
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• 2004

This paper focuses on the DSP implementation of an HMM-based speech recognizer that can handle several hundred words of vocabulary size as well as speaker independency. First, we develop an HMM-based speech recognition system on the PC that operates on the frame basis with parallel processing of feature extraction and Viterbi decoding to make the processing delay as small as possible. Many techniques such as linear discriminant analysis, state-based Gaussian selection, and phonetic tied mixture model are employed for reduction of computational burden and memory size. The system is then properly optimized and compiled on the TMS320C6711 DSP for real-time operation. The implemented system uses 486kbytes of memory for data and acoustic models, and 24.5 kbytes for program code. Maximum required time of 29.2 ms for processing a frame of 32 ms of speech validates real-time operation of the implemented system.

• Earthquakes and Structures
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• v.14 no.2
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• pp.143-153
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• 2018

Correlation among different factors must be considered for selection of influencing factors in safety monitoring of high dam including positive correlation of variables. Therefore, a new factor selection method was constructed based on Copula entropy and mutual information theory, which was deduced and optimized. Considering the small sample size in high dam monitoring and distribution of daily monitoring samples, a computing method that avoids causality of structure as much as possible is needed. The two-dimensional normal information diffusion and fuzzy reasoning of pattern recognition field are based on the weight theory, which avoids complicated causes of the studying structure. Hence, it is used to dam safety monitoring field and simplified, which increases sample information appropriately. Next, a complete system integrating high dam monitoring and uncertainty prediction method was established by combining Copula entropy theory and information diffusion theory. Finally, the proposed method was applied in seepage monitoring of Nuozhadu clay core-wall rockfill dam. Its selection of influencing factors and processing of sample data were compared with different models. Results demonstrated that the proposed method increases the prediction accuracy to some extent.

• Management & Information Systems Review
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• v.7
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• pp.265-292
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• 2001

This paper examines what determines the use of contingent workers in Korean Department Stores. Drawing on internal labor market, transaction cost & agency, and bureaucracy theories, I hypothesize that four factors affect the use of contingent workers: job characteristics, HRM, occupation, and organizational characteristics. Data from a sample of employers surveyed by the author in 1997 were used to test the hypotheses, and analyses showed the following results. First, consistent with job-based perspective, we find that such job characteristics as firm-specific skill and the level of skill significantly affect the use of contingent workers. But job standardization and outcome measurability have no effects of its use. Second, also we find significant effects on the use of contingent workers of such HRM as scrutiny on employee selection and promotion system. The promotion system has expected effect on its use, but scrutiny on employee selection has opposite effect. Third, we find that occupation significantly affects the use of contingent workers, especially the extent of use of contingent workers of sales service is as five hundred times as that of managerial occupation. Fourth, also consistent with organizational-based perspective, we find that the firm's size significantly has positive effects, and affiliate company and labor union have negative effects. That is, the larger firm's size is, the more possibility of use of contingent workers exists, and the possibilities of its use reduce in case of affiliate company and in front of labor union. Finally, we discuss the implications and limits of theses findings.