• Journal of Power Electronics
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• v.4 no.1
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• pp.1-11
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• 2004

A stable adaptive sensorless speed controller for three-level inverter fed induction motor direct torque control (DTC) system using the radial-basis function network (RBFN) is presented in this paper. Torque ripple in the DTC system for high power induction motor could be drastically reduced with the foregoing researches of switching voltage selection and torque ripple reduction algorithms. However, speed control performance is still influenced by the inherent uncertainty of the system such as parametric uncertainty, external load disturbances and unmodeled dynamics, and its exact mathematical model is much difficult to be obtained due to their strong nonlinearity. In this paper, the inherent uncertainty is approximated on-line by the RBFN, and an additional robust control term is introduced to compensate for the reconstruction error of the RBFN instead of the rich number of rules and additional updated parameters. Control law for stabilizing the system and adaptive laws for updating both of weights in the RBFN and a bounding constant are established so that the whole closed-loop system is stable in the sense of Lyapunov, and the stability proof of the whole control system is presented. Computer simulations as well as experimental results are presented to show the validity and effectiveness of the proposed system.

• Journal of Information Technology Services
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• v.13 no.1
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• pp.23-42
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• 2014

This study investigates the impact of Internet Banking Systems on the business performance of bank. Although Internet Banking Systems were introduced about 15 years ago in Korea, there were few studies which evidenced the relationship between Internet Banking Systems and the performance of banks. For this empirical investigation, this study collected the panel data of 13 domestic banks over 8.5 years and divided the dataset into two parts-the first half period (2003~2007) and the second half period (2008~2011) in order to examine the dynamic changes in the impact of Internet Banking Systems. The fixed-effects panel regression results were different in the two parts of dataset. Internet Banking Systems showed only cost-efficiency impact in the first half period. However, in the second half period, Internet Banking Systems showed positive impact on the bank profitability. Moreover, the dummy variable regarding local bank showed no additional impact on this result, implying that the impact of Internet Banking Systems was still significant for the local banks. The results will deliver managerial interpretation on the value of Internet Banking Systems and additional implication on the strategic planning of Internet Banking Systems for many domestic banks.

• Journal of Digital Contents Society
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• v.8 no.3
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• pp.347-353
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• 2007

As the number of channels and programs are increasing dramatically, a viewer seriously needs to book a program at the very time of watching its promotion program by "only one time" pressing remote controller's button. The program reserving system requiring to search a program via EPG is usually hard to operate and some researches that allow a viewer to book a program via its promotion program require additional heavy facilities such as image processing or ultra-frequency recognizing systems. In this paper, a new program reservation system is introduced. the system allows a viewer to book a program via its promotion program. The system is conformable to MHP (which is the data service standard most widely adopted in the world) so that the broadcasting stations need no additional equipments to implement it as long as they follow the MHP standard.

• Health Policy and Management
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• v.25 no.1
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• pp.53-62
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• 2015

Background: Supplier induced demand (SID) indicates the case when doctors increase the demand of the patients, following their (physicians') own best interests rather than patients'. This may occur when asymmetry of information exists between suppliers and consumers. This study aims to confirm whether SID exists in the Korean setting, particularly by dividing SID into both 'induced demand effect' and 'availability effect.' Methods: Induced demand effect and availability effect are differentiated following Carlsen & Grytten's theoretical frame which divides doctor density regions into high and low ones. Results: Positive correlation between doctors' density and utilization of their services was found, which could be interpreted as 'availability effect.' Conclusion: The result suggests that additional medical use for additional doctor, particularly in the area of low doctor density, can be interpreted to occur to meet the basic medical need of the people rather than as a result of unnecessary induced demand. It is important to make more medical doctors provided and to distribute them appropriately across the region in such a country like Korea where doctor's density is relatively low.

• Journal of Korean Foot and Ankle Society
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• v.22 no.2
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• pp.55-61
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• 2018

Chronic lateral ankle instability is a major complication of acute ankle sprains, which can cause discomfort in both daily and sports activity. In addition, it may result in degenerative changes to the ankle joint in the long term. An accurate diagnostic approach and successful treatment plan can be established based on a comprehensive understanding of the concept of functional and mechanical instability. The patients' history and correct physical examination would be the first and most important step. The hindfoot alignment, competence of the lateral ligaments, and proprioceptive function should be evaluated. Additional information can be gathered using standard and stress radiographs. In addition, concomitant pathologic conditions can be investigated by magnetic resonance imaging. Conservative rehabilitation composed of the range of motion, muscle strengthening, and proprioceptive exercise is the main treatment for functional instability and mechanical instability. Regarding the mechanical instability, surgical treatment can be considered for irresponsible patients after a sufficient period of rehabilitation. Anatomic repair (modified $Brostr{\ddot{o}}m$ operation) is regarded as the gold standard procedure. In cases with poor prognostic factors, an anatomical reconstruction or additional procedures can be chosen. For combined intra-articular pathologies, arthroscopic procedures should be conducted, and arthroscopic lateral ligament repair has recently been introduced. Regarding the postoperative management, early functional rehabilitation with short term immobilization is recommended.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.5
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• pp.375-381
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• 2001

As the device geometry continuously shrink down less than sub-quarter micrometer, DRAM makers are going to replace conventional tungsten-polycide bit-line with tungsten bit-line structure in order to reduce the chip size and use it as a local interconnection. In this paper we showed low resistance tungsten bit-line fabrication process with various RTP(Rapid Thermal Process) temperature and additional ion implantation. As a result we obtained that major parameters impact on tungsten bit-line process are RTP Anneal temperature and BF$_2$ ion implantation dopant. These tungsten bit-line process are promising to fabricate high density chip technology.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.3
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• pp.331-340
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• 2012

In the deep sub-micron ICs, growing amounts of on-die memory and scaling effects make embedded memories increasingly vulnerable to reliability and yield problems. Spare columns are often included in memories to repair defective cells or bit lines during production test. In many cases, the repair process will not use all spare columns. Schemes have been proposed to exploit these unused spare columns to store additional check bits which can be used to reduce the miscorrection probability for triple errors in single error correction-double error detection (SEC-DED). These additional check bits increase the dimensions of the parity check matrix (H-matrix) requiring extra area overhead. A method is proposed in this paper to efficiently fill the extra rows of the H-matrix on the basis of similarity of logic between the other rows. Optimization of the whole H-matrix is accomplished through logic sharing within a feasible operating time resulting in reduced area overhead. A detailed implementation using fuse technology is also proposed in this paper.

• Molecules and Cells
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• v.19 no.2
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• pp.180-184
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• 2005

IL-17 is a major proinflammatory cytokine secreted by activated T-lymphocytes that accumulates in the inflamed joints of rheumatoid arthritis (RA) patients. Additional IL-17-related molecules and their receptors have been discovered and may also contribute to RA pathogenesis. We examined the expression of the prototypic IL-17 (IL-17A) and its homologs, IL-17B-F, by RT-PCR analyses of synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from RA patients. We also tested for induction of the IL-17 receptor homologs upon stimulation of the fibroblast-like synoviocytes (FLSs) of RA patients with IL-17. The patients' SFMCs expressed IL-17C, E and F in addition to IL-17A. As in the case of IL-17, IL-15 appears to be the major inducer of these homologs in RA SFMCs. We detected transcripts of IL-17R, as well as those of IL-17RB, C and D, in the FLSs of RA patients. Whereas IL-17R expression increased upon in vitro stimulation with IL-17, expression of IL-17RB, C and D was unchanged. However the possibility of cross-interaction between other IL-17 homologs and receptor isoforms remains to be investigated. Our data suggest that these additional homologs should also be considered as targets for immune modulation in the treatment of RA joint inflammation.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.3_4
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• pp.160-167
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• 2003

A static shuffle-exchange network is not only useful for several parallel applications but also use less hardware than the popular multi-stage network or hypercube. Even though it has a lot of advantages, it has never been used in any implemented parallel machine. One of the reasons is there has not been any techniques to make the network fault-tolerant. In this paper multiple fault-tolerant static shuffle-exchange networks are presented. In order to recover from k faulty processing elements, a network needs at least 2 k additional processing elements and at most 4 k additional shuffle ports for each processing elements. By decomposing the k fault-tolerant static shuffle-exchange network into m identical modules, this paper shows that the reliability of the network can be increased.

• Journal of Korean Public Health Nursing
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• v.12 no.1
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• pp.13-22
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• 1998

This study was conducted to find qualitative approaches to occupational reference to group health practices. In-depth interviewing was done on 8 subjects health monitor members, owners and occupational nurses, respectively). The major findings were as follows; 1. Visiting health management Useful services were 'health counseling', 'medical examination', 'providing informations about managing diseases', 'agency business in relation to Labour Ministry' and 'giving a recognition about occupational health service to owners'. Insufficiencies were 'lack of treatment service after medical examination' and 'lack of follow up services constantly'. 2. Occupational nursing service Useful services were 'providing health information' and 'counselling about health'. Major contents of occupational nursing services were 'management of occupational and adult diseases' and 'explanation of the results after medical examination'. Insufficiencies were 'deficiency of the place where group health education could be performed', 'lack of additional or closer examinations needed in counselling' and 'discontinuous selection of additional or more exact examinations'. 3. Health monitor members Health monitor members in industries were classified into two. Some were selected by owners and the others were selected simply by considering their administrative abilities such as proficient management of documents. Their major tasks were to connect workers with occupational health management agencies. This study suggests that programs should be developed which enable health monitor members to cooperate with occupational nurses.