• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3310-3316
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• 2022

Owing to the rising concerns about the safety of nuclear power plants (NPP), it is essential to study the venturi scrubber in detail, which is a key component of the filtered containment venting system (FCVS). FCVS alleviates the pressurein containment byfiltering and venting out the contaminated air. Themain objective of this research was to perform a CFD investigation of different configurations of a circular, non-submerged, self-priming venturi scrubber to estimate and improve the performance in the removal of elemental iodine from the air. For benchmarking, a mass transfer model which is based on two-film theory was selected and validated by experimental data where an alkaline solution was considered as the scrubbing solution. This mass transfer model was modified and implemented on a unique formation of two self-priming venturi scrubbers in series. Euler-Euler method was used for two-phase modeling and the realizable K-ε model was used for capturing the turbulence. The obtained results showed a remarkable improvement in the removal of radioactive iodine from the air using a series combination of venturi scrubbers. The removal efficiency was improved at every single data point.

• Journal of the Korean Society of Safety
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• v.37 no.5
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• pp.80-88
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• 2022

The Korean nuclear industry had developed the SPACE (Safety and Performance Analysis Code for nuclear power plants) code, which adopts a two-fluid, three-field model that is comprised of gas, continuous liquid and droplet fields and has the capability to simulate three-dimensional models. According to the revised law by the Nuclear Safety and Security Commission (NSSC) in Korea, the multiple failure accidents that must be considered for the accident management plan of a nuclear power plant was determined based on the lessons learned from the Fukushima accident. Generally, to improve the reliability of the calculation results of a safety analysis code, verification is required for the separate and integral effect experiments. Therefore, the goal of this work is to verify the calculation capability of the SPACE code for multiple failure accidents. For this purpose, an experiment was conducted to simulate a Control Element Drive Mechanism (CEDM) break with a safety injection failure using the ATLAS test facility, which is operated by Korea Atomic Energy Research Institute (KAERI). This experiment focused on the comparison between the experiment results and code calculation results to verify the performance of the SPACE code. The results of the overall system transient response using the SPACE code showed similar trends with the experimental results for parameters such as the system pressure, mass flow rate, and collapsed water level in component. In conclusion, it can be concluded that the SPACE code has sufficient capability to simulate a CEDM break with a safety injection failure accident.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.93-100
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• 2022

The use of innovative technologies is one of the promising areas of education development, so the article clarifies the content of the terms "innovation" "pedagogical technology". Our goal is to justify the need to use innovative technologies in education. Innovative technologies are divided into four groups, depending on the appropriate form of educational activity for their use. The development of innovative pedagogical technologies at the present stage of education development should be carried out in accordance with the criteria of technological efficiency, which are presented in the article: scientific; systematic; guaranteed; manageable; mass. Based on the analysis of the process of formation of pedagogical education, the main trends in the information support of teachers in the system of pedagogical education were revealed. Its theoretical and methodological foundations were determined, promising directions and main ways of improving the information support of teachers' education as an organic component of continuous pedagogical education in Ukraine were justified. The conducted study of the state of information support for teachers allowed us to establish that the main functions of scientific and pedagogical information - analytical and predictive, integrative, operational and purposeful informing of various categories of specialists - teachers-are not being implemented enough. This is due to the versatility and complexity of the pedagogical process, the low level and limited range of development of systems of operational differentiated scientific and methodological services for various categories of teachers. Ways to improve the information function of teacher education are determined.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.3
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• pp.227-233
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• 2023

In this paper, to substitute the existing TWTA(Travailing Wave Tube Amplifier) component in small radar system, we developed the Ku band SSPA(Solid-State Power Amplifier) based on the fabrication of power MMIC (Monolithic Microwave Integrated Circuit) chips. For the development of the 500 W SSPA, the 40 W-grade power MMIC was designed by ADS(Advanced Design System) at Keysight company with UMS GH015 library, and was processed by UMS foundry service. And 70 W main power modules were achieved the 2-way T-junction combiner method by using the 40 W-grade power MMICs. Finally, the 500 W SSPA was fabricated by the wave guide type power divider between the drive power amplifier and power modules, and power combiner with same type between power modules and output port. The electrical properties of this SSPA had 504 W output power, -58.11 dBc spurious, 1.74 °/us phase variation, and -143 dBm/Hz noise level.

• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.909-919
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• 2023

Benthic marine invertebrates, the invertebrates living on the bottom of the ocean, are an essential component of the marine ecosystem, but excessive reproduction of invertebrate grazers or pirate creatures can cause damage to the coastal fishery ecosystem. In this study, we compared and evaluated You Only Look Once Version 7 (YOLOv7), the most widely used deep learning model for real-time object detection, and detection tansformer (DETR), a transformer-based model, using underwater images for benthic marine invertebratesin the coasts of South Korea. YOLOv7 showed a mean average precision at 0.5 (mAP@0.5) of 0.899, and DETR showed an mAP@0.5 of 0.862, which implies that YOLOv7 is more appropriate for object detection of various sizes. This is because YOLOv7 generates the bounding boxes at multiple scales that can help detect small objects. Both models had a processing speed of more than 30 frames persecond (FPS),so it is expected that real-time object detection from the images provided by divers and underwater drones will be possible. The proposed method can be used to prevent and restore damage to coastal fisheries ecosystems, such as rescuing invertebrate grazers and creating sea forests to prevent ocean desertification.

• Journal of KIISE:Software and Applications
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• v.30 no.10
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• pp.904-911
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• 2003

In this paper, we propose an effective method for the distinction between machine-printed and handwritten Korean address images. It is important to know whether an input image is handwritten or machine-printed, because methods for handwritten image are quite different from those of machine-printed image in such applications as address reading, form processing, FAX routing, and so on. Our method consists of three blocks: valid connected components grouping, feature extraction, and classification. Features related to width and position of groups of valid connected components are used for the classification based on a neural network. The experiment done with live Korean address images has demonstrated the superiority of the proposed method. The correct classification rate for 3,147 testing images was about 98.85%.

• International Journal of Control, Automation, and Systems
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• v.3 no.4
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• pp.571-579
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• 2005

In this paper, we proposed an algorithm for arrhythmia classification, which is associated with the reduction of feature dimensions by linear discriminant analysis (LDA) and a support vector machine (SVM) based classifier. Seventeen original input features were extracted from preprocessed signals by wavelet transform, and attempts were then made to reduce these to 4 features, the linear combination of original features, by LDA. The performance of the SVM classifier with reduced features by LDA showed higher than with that by principal component analysis (PCA) and even with original features. For a cross-validation procedure, this SVM classifier was compared with Multilayer Perceptrons (MLP) and Fuzzy Inference System (FIS) classifiers. When all classifiers used the same reduced features, the overall performance of the SVM classifier was comprehensively superior to all others. Especially, the accuracy of discrimination of normal sinus rhythm (NSR), arterial premature contraction (APC), supraventricular tachycardia (SVT), premature ventricular contraction (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF) were $99.307\%,\;99.274\%,\;99.854\%,\;98.344\%,\;99.441\%\;and\;99.883\%$, respectively. And, even with smaller learning data, the SVM classifier offered better performance than the MLP classifier.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.77-86
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• 2007

Web services are considered as the critical component in the business plans of corporations as they offers the potential for creating highly dynamic and versatile distributed applications that span across business boundaries. Web Service Orchestration studies composition of already-existing web services to create new value-added services. The composite web services could be executed in a centralized or peer-to-peer(P2P) orchestration model. Compared with centralized-orchestration model, the P2P-based orchestration model provides better scalability, reliability, and performance for the overall services. However, recent P2P-orchestration solutions have limitation in supporting complex workflow patterns. Therefore, they could not effectively handle sophisticated business workflow, which contains complex workflow patterns. In this paper, we propose the WORKGLOW system, which can deal with complex workflow patterns while it is able to perform composite services in P2P orchestration manner. Comparing with centralized orchestration systems, the WORKGLOW brings up more business logic advantages, better performance, and higher flexibility with only a little overhead.

• Journal of Korean Academy of Nursing
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• v.26 no.2
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• pp.345-358
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• 1996

All human health behavior is deeply rooted one's beliefs or value system usually encompassed within the culture in which they live. The Taegyo, based on Oriental folk medicine, is defined as the behavior and self care of pregnant women administered for herself and her fetus(unborn child). Taegyo is believed to be desirable, effective, and healthy behavior by most of Korean pregnant women. It is essential in our contemporary culture, to ascertain what the components of Taegyo are and to integrate them into current, western nursing care, particularly in the area of prenatal care. 910 Korean women were the subjects of this study, who were in a gestation period of pregnancy between 10 weeks to three months postpartum. The subjects were selected by clustered smpling from 10 representative cities in Korea. Data was collected from February 10 to March 30 1995 by a constructed Questionnaire which consisted of 95 items. The questionnaire was developed through three steps such as content analysis, calculation of content validity index, and pretest. Data was analyzed by descriptive statistics and rotated matrix factor analysis with pc-SAS. The mean age of the subjects was 28.9 years : 36.5％ of them were employed and the mean income per month was about 2000 dollars. The component of Taegyo was clustered into five factors such as fetus psychological stability(equity), fetus personality development, maternal-fetal interaction, fetus intellectual development and physical health promotion. The variance of each factor were 23.7％, 8.3％, 4. 7％, 4.1％, and 3.3％ respectively in that order. The Eigen value of each factor was 13.03, 4.57, 2.60, 2.23, and l.83 respectively. It was found that the Taegyo is an unique and holistic self care behavior of Korean pregnant women. Therefore it has been concluded that this study has broadened the understandability of the implications the Taegyo. It is suggested that further studies on the effects of the Taegyo are needed to provide a scientific basis for professional maternity nursing.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.2
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• pp.18-25
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• 2008

The traditional a roaches to software development, such as XP, UP, CBD and other CASE tools, are useful for constructing various software components. However, they are not designed to face the challenges of open environments that focus on service. The Service-Oriented Architecture(SOA) is a component architecture that interconnects an application's different functional units, called services. SOA provides a good way to integrate the business process through well-defined interfaces and contracts between business services. In this paper, we propose a method of business process modeling based on SOA with a P2P approach. Also, A P2P business process modeling system is presented. This, results in admitting the reality of enterprise that changes on the basis of services, and suggests more efficient and visual direction for the process integration between enterprises.