• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.145-150
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• 2006

At the furnace top, the distribution of charging coke and ore is adjusted to control the reducing gas flow distribution in the furnace. It is necessary to predict operation condition of blast furnace according to the burden profile to judge whether charging is properly conducted In this study, We propose the model for predicting while layer structures whithin furnace when top burden profile was given. Layer structure of coke and ore could be predicted by top burden profile and solid velocity. Solid velocity is assumed as potential flow. Potential function distribution and timeline are also calculated using solid velocity field. The Calculation is conducted for different burden profile cases. As the result burden distribution and grid structure, which is deformed to match the layer structure in shaft and deadman profile. Gas flow was calculated using this grid, and calculated results are compared with each other.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1037-1041
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• 2007

With the advent of sound field simulator, many sound fields have been reproduced by obtaining the impulse responses of specific acoustic spaces like famous concert hall, opera house. This sound field reproduction has been done by the linear convolution operation between the sound input signal and the impulse response of certain acoustic space. However, the conventional finite impulse response based linear convolution operation always makes real-time implementation of sound field generator impossible due to the large amount of computational burden. This paper introduces the fast convolution method using perceptual redundancy in the processed signals, input audio signal and room impulse response. Temporal and spectral psycho-acoustic filters considering masking effects are implemented in the proposed convolution structure. It reduces the computational burden of convolution methods for realtime implementation of a sound field generator. The conventional convolutions are compared with the proposed one in views of computational burden and sound quality. In the proposed method, a considerable reduction in the computational burden was realized with acceptable changes in sound quality.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.231-237
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• 2008

With the advent of sound field simulator, many sound fields have been reproduced by obtaining the impulse responses of specific acoustic spaces like famous concert hall, opera house. This sound field reproduction has been done by the linear convolution operation between the sound input signal and the impulse response of certain acoustic space. However, the conventional finite impulse response based linear convolution operation always makes real-time implementation of sound field generator impossible due to the large amount of computational burden. This paper introduces the fast convolution method using perceptual redundancy in the processed signals, input audio signal and room impulse response. Temporal and spectral real-time masking blocks are implemented in the proposed convolution structure. It reduces the computational burden of convolution methods for real-time implementation of a sound field generator. The conventional convolutions are compared with the proposed one in views of computational burden and sound quality. In the proposed method, a considerable reduction in the computational burden was realized with acceptable changes in sound quality.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.5
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• pp.1073-1077
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• 2011

The breaking capacity of circuit breakers could be no more increased in the electric power system. This is because the fault current increases due to continuous increases in electric power demand and facilities. To solve the problem, it is necessary to come up with an alternative. The superconducting fault current limiter (SFCL) has received an attention among various alternatives. The SFCL effectively reduce a fault current in cooperation with a power circuit breaker. A various types of the SFCL are suggested and a study on them have been progressed. As a result of it, the SFCL can be applyed to the electric power system in the near future. But, a study on recovery behaviors of the SFCL is not enough for applying to the electric power system. If the superconducting elements do not completely recover to the superconducting state after fault operation, it might be a breakdown of the superconducting elements due to heavy power burden and it gives an bad influence on the working of other electric devices. Additionally, the distribution power system has reclosing operation such as open-0.3sec-closed/open-3min-closed/open procedure. So we need to study more about improvement of the recovery behaviors of the SFCL. In this paper, we analyzed the recovery behaviors of a flux-coupling type SFCL according to reclosing operation when a single line-to-ground fault occurred and we compared recovery behaviors of the SFCL with and without a neutral line between secondary reactors and superconducting elements. Also, the flux-coupling type SFCL has advantageous for increases of capacity by controlling the variation in turn ratios between two reactors. Consequently, when the number of turns of the secondary reactors increased, the power burden of the superconducting elements was bigger due to the increase of impedances of the secondary reactors. To distribute the power burden, two superconducting elements connected in series and the balanced quenching of the superconducting elements was induced by connecting a neutral line.

• Nuclear Engineering and Technology
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• v.44 no.4
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• pp.379-386
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• 2012

A symptom-based procedure with a critical safety function monitoring system has been established to reduce the operator's diagnosis and cognitive burden since the Three-Mile Island (TMI) accident. However, it has been reported that a symptom-based procedure also requires an operator's cognitive efforts to cope with off-normal events. This can be caused by mismatches between a static model, an emergency operating procedure (EOP), and a dynamic process, the nature of an ongoing situation. The purpose of this study is to share the evidence of mismatches that may result in an excessive cognitive burden in conducting EOPs. For this purpose, we analyzed simulated emergency operation records and observed some operator behaviors during the EOP operation: continuous steps, improper description, parameter check at a fixed time, decision by information previously obtained, execution complexity, operation by the operator's knowledge, notes and cautions, and a foldout page. Since observations in this study are comparable to the results of an existing study, it is expected that the operational behaviors observed in this study are generic features of operators who have to cope with a dynamic situation using a static procedure.

• Journal of the Korean Dietetic Association
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• v.5 no.1
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• pp.74-84
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• 1999

The purpose of this study was to investigate a plan of middle/high school foodservice systems which could properly provide nutrition for juveniles' health. Questionnaires were developed and distributed to: 245 middle schools with 271 parents, 328 students, 180 teachers, and 345 administrators; 163 high-schools with 223 parents, 466 students, 179 teachers, and 163 administrators in Seoul and Kyunggi province. The results of this study were as followed. For the desirable feeding type as in-school meal plan, 62.2% responded to the current elementary school feeing type:10.3% responded to a lunch-box prepared at home; and 38.0% responded to free dining out type. For a feeding operation type, school administrators, teachers and parents favored the current school feeding systems in elementary schools with proportion of 68.2%, 47.7%, and 87.6% as respectively. Also, 20.3% of school administrators, 22.6% of teachers, and 6.9% of parents preferred contract management. A total of 27.6% of teachers, 9.2% of school administrators, and 3.7% of parents responded to a lunch-box prepared at home. There was a significant difference between the responses for establishing the main body of financial burden to solve the problem of financial burden which could be the most obstacle to bring middle/high school feeding system into operation. For the management of school feeding systems when brought into operation, 88.7% out of 470 responded schools and 89.9% out of 227 responded teachers reported that an expert should manage school feeding systems. For futuristic direction, an effective joint cooking type between schools which may be the way to solve the difficulties in securing the appropriate space and to decrease the financial burden, the problem of transportation for delivering feeding products, low quality of feeding, and sanitation can occur. Therefore, the distance between schools which operate a joint cooking system will affect as a major factor. Furthermore, concrete examination of plans for introduction of various types of school feeding and institutional devices for management system and supervision of operation should become a condition precedent.

• Progress in Superconductivity and Cryogenics
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• v.19 no.2
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• pp.33-37
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• 2017

To protect the power systems from fault current, the rated protective equipment should be installed. However growth of power system scale and concentration of loads caused the large fault current in power transmission system and distribution system. The capacities of installed protective equipment have been exceeded the due to increase of fault current. This increase is not temporary phenomenon but will be steadily as long as the industry develops. The power system operator need a counter-measurement for safety, so superconducting fault current limiter (SFCL) has been received attention as effective solutions to reduce the fault current. For the above reasons various type SFCLs have been studied recently. In this paper, operation characteristics and power burden of trigger type SFCL is studied. The trigger type SFCL has been used for real system research in many countries. Another trigger type SFCL (double quench trigger type SFCL) is also studied. For this paper, short circuit test is performed.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.449-453
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• 2006

Purpose: Perceiving the experience that $MRD_1$ is increased after small-incision double-eyelid operation, it has been statistically verified the improvement of $MRD_1$ retrospectively. Therefore, we suggest new interpretation for Korean-specific small eye and more definite classification for ptosis. Methods: In operation, we made 3 small incisions according to the line designed on upper eyelid and removed some soft tissues including connective tissues. Then, figure-of-8 continuous buried ligation was performed through the incision windows. This study is a retrospective study, measures $MRD_1$ changes and excursion distance change of eyelid margine and eyebrow using pre-and post-operative photos of 14 patients. Results: Postoperative photos were taken on the 4th day and all of 14 patients had an improvement in $MRD_1$ statistically. The excursion distance of upper eyelid was improved in half of patients, though not in the range of statistical verification. It was statistically confirmed that the movement of eyebrow was reduced after operation. Conclusion: It is thought that $MRD_1$ improvement without any operation on levator complex means that soft tissue including connective tissue eliminated in operation restricts the movement of upper eyelid. It is defined such factors as burden factors and such phenomenon as burdened eyelid. It is thougt that Korean's small eye is mainly burdened eyelid and cosmetic improvement may be obtaind even by removing such burden factors.

• International Journal of Advanced Culture Technology
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• v.10 no.1
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• pp.180-186
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• 2022

This study is a pilot study to confirm the effectiveness of training after applying emergency simulation training for inactive nurses and to present a new model of simulation training operation method. In this study, the control group is a group that directly participates in the simulation activity, and the experimental group is the group that observes the control group's simulation activity. Experimental group and control group were matched 1:1 to experience all the roles of the resuscitation team. The study participants were 5 inactive nurses in the experimental group and 5 inactive nurses in the control group, and the total training time was 5 hours. The emergency simulation operation composition consists of theory education, skill education, and simulation. The interview was conducted. The educational satisfaction of the participants was 4.65 points for theory education and 4.70 points for practical education based on 5 points. Participants' performance confidence improved from 3.60 points before operation to 7.20 points after operation. Emergency simulation operation consisted of pre-test, theory education, skill education, simulation implementation, debriefing, and post-test. Participants expressed that the choice of group greatly reduced the burden and anxiety about performing the role of the resuscitation team. However, difficulties and inexperience in the operation of the defibrillator were reported in the experimental group. The control group reported that the simulation activity of the experimental group was not significantly different from theirs. Through the results of this study, it was confirmed that emergency simulation education not only reduced the burden and anxiety of inactive nurses, but also had an effect of education. Based on the research results, it is proposed to expand the participants and verify the effectiveness of education through specific variables such as learning commitment, learner confidence, simulation satisfaction, and team effectiveness.

• The Korean Society of Law and Medicine
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• v.9 no.1
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• pp.129-162
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• 2008

Nowadays it is important for us to resolute medical disputes. Because a high incidence of medical accidents may be brought about according to many chances of treatment in the operation of health insurance and increasing concern of patient health. Patients and medical doctors have plenty of difficulty in uncomfortable treatment circumstances of a high incidence of medical accidents. It is especially desirable that our society should prevent medical accidents and resolute speedy, fairly and rationally the happened medical disputes. Many legislations were suggested to resolute medical dispute. But legal issue points stress only speedy medical dispute resolution procedure and don't compromise fair and professional procedure. Accordingly these legal arguing points had not been accepted by the National Assembly and people. If the speedy resolution of medical dispute was demanded to solve unsafe treatment circumstances, it is necessitated that the legislation containing legal issue points to procedure is enacted. Of course the interest of patients and doctors to legal issue points must be balanced. Because an arguing points to the reversal of proof burden is consisted of the entity judgement in connection with setting the basis of resolution of medical dispute, the legislation to these is checked carefully.