• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.12
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• pp.889-898
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• 2022

In this paper, parallel computing method on the three-dimensional electromagnetic field is proposed. The present electromagnetic scattering analysis is conducted based on the time-harmonic vector wave equation and the finite element method. The edge-based element and 2^nd -order absorbing boundary condition are used. Parallelization of the elemental numerical integration and the matrix assemblage is accomplished by allocating the partitioned finite element subdomain for each processor. The graph partitioning library, METIS, is employed for the subdomain generation. The large sparse matrix computation is conducted by MUMPS, which is the parallel computing library based on the multi-frontal method. The accuracy of the present program is validated by the comparison against the Mie-series analytical solution and the results by ANSYS HFSS. In addition, the scalability is verified by measuring the speed-up in terms of the number of processors used. The present electromagnetic scattering analysis is performed for a perfect electric conductor sphere, isotropic/anisotropic dielectric sphere, and the missile configuration. The algorithm of the present program will be applied to the finite element and tearing method, aiming for the further extended parallel computing performance.

• The Korean Journal of Emergency Medical Services
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• v.26 no.2
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• pp.97-111
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• 2022

Purpose: Automated External Defibrillator (AED) usage in out-of-hospital cardiac arrests (OHCAs) improves the survival of patients. In Singapore, public AEDs are protected by locked boxes with a 'break glass' mechanism to deter theft. Community responders have sustained injuries while breaking glass to retrieve AEDs. This unprecedented study aimed to elucidate the factors influencing successful retrieval of an AED and to document the prevalence of injuries. Methods: A survey was created and distributed. Participants were required to have responded to an OHCA in the past 12 months. Comparison tests were performed with the Fischer-Freeman-Halton Exact test or Pearson chi square test at 5% significance levels, and with multiple logistic regression with a logit link function. Results: Eighty-eight participants were eligible. The success of retrieving an AED was found not to be impacted by occupation, age, gender or time. Participants who responded to an OHCA because of activation by the myResponder App were more likely to retrieve an AED successfully. (AOR 11.111, 95% CI: 2.141-58.824) Conclusion: Use of the myResponder mobile application is associated with the greater success of retrieving an AED. Successful retrieval of an AED is not impacted by time, gender, age, or the occupation of the responder. Community responders in Singapore remain motivated to respond to Cardiac Arrests despite risk of injury.

• Maritime Security
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• v.4 no.1
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• pp.115-138
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• 2022

The Korean military is preparing for successful manpower reduction using advanced science and technology, in addition to carrying out the initiative of the Defense Innovation 4.0. Accordingly, studies on core technologies related to defense reform have been conducted both internally and externally in the military, and the corresponding results have also been applied. Nevertheless, compared to the development of such technologies, it is considered necessary to have more preparation for the policies related to the operation of the newly introduced equipment. As for the placement of personnel and the organization of time in service (TIS) with respect to the operation of surveillance equipment, there has been a tendency to sustain the conventional practice. Therefore, this study intends to suggest the schemes for facilitating policy improvements in the operation of manpower and security regulations in the field of information for the purpose of introducing a successful next-generation coastal guard system. To do this, the approach of this study was focused on the policies for the operation of the guard system. This is in contrast to previous studies that centered on its equipment and technologies. In addition, how to efficiently operate the guard system was also studied in view of cognitive science by deriving the most efficient time for a person to execute surveillance through the monitor based on the previous studies.

• Ocean and Polar Research
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• v.45 no.3
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• pp.141-153
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• 2023

Biological pump processes generated by diatom production in the surface water of the Southern Ocean play an important role in exchanging CO₂ gas between the atmosphere and ocean. In this study, the biogenic opal content of the sediments was measured to elucidate the variation in the primary production of diatoms in the surface water of the Southern Ocean since the last glacial period. A piston core (COR-1bPC) was collected from the Conrad Rise, which is located in the Indian sector of the Southern Ocean. The sediments were mainly composed of siliceous ooze, and sediment lightness increased and magnetic susceptibility decreased in an upward direction. The biogenic opal content was low (38.9%) during the last glacial period and high (73.4%) during the Holocene, showing a similar variation to that of Antarctic ice core ΔT and CO₂ concentration. In addition, the variation of biogenic opal content in core COR-1bPC is consistent with previous results reported in the Antarctic Zone, south of the Antarctic Polar Front, in the Southern Ocean. The glacial-interglacial biogenic opal production was influenced by the extent of sea ice coverage and degree of water column stability. During the last glacial period, the diatom production was reduced due to the penetration of light being limited in the euphotic zone by the extended sea ice coverage caused by the lowered seawater temperature. In addition, the formation of a strong thermocline in more extensive areas of sea ice coverage led to stronger water column stability, resulting in reduced diatom production due to the reduction in the supply of nutrient-rich subsurface water caused by a decrease in upwelling intensity. Under such environmental circumstances, diatom productivity decreased in the Antarctic Zone during the last glacial period, but the biogenic opal content increased rapidly under warming conditions with the onset of deglaciation.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.15-15
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• 2023

2020년 기준 국내 상수도 보급률은 99.1% 차지하고 있으며(환경부, 2019), 수도관리차원에서 수돗물은 먹는 물로 시판되어질 만큼 우수한 관리체계를 유지하고 있다. 그 반면에 지하수는 생활용수, 식품가공, 농·축산, 양어, 군부대를 비롯한 전국지역에서 연간 10억 8천만톤 용수를 소비하고 있음에도 (환겨례 신문, 2013; 환경부, 2019) 사용되는 지하수의 약 65%가 음용수 불가판정을 받았으며, 최근 지하수의 오염비율은 급격히 증가하는 추세이다. 특히, 지하수관정의 관리부주의에 의한 수질오염 및 수인성 다제내성균(슈퍼박테리아) 등에 의한 오염사례가 국내는 물론, 국제적으로 다수 보고되고 있는 실정이다 (환경부, 2013). 현재 지하수 수질관리는 공공기관 및 지자체 지정기관을 통해 진행되고 있으며, 검사기간은 수질채취로부터 통상 7~15일정도 소요되어 수질 관리 및 기준, 검사주기에 대한 애로가 많다. 현장 지하수관정에서 실시간 수질을 모니터링하고 이에 연동된 자동 수처리 시스템의 개발 및 도입은 나날이 심각해지는 환경오염 상황에서 선제적 예방과 해결방법으로 중요한 요소기술이다. 현재 지하수오염 및 부적합 음용의 수질처리는 화학약품, 필터여과, UV살균, O₃ (플라즈마)을 이용하는 것이 대표적이나, 화학약품의 경우 2차 오염이나 식품 세척 및 가공에 있어 부적합성의 한계점이 있다. 필터여과의 대표적인 RO필터의 경우 약 50% 순손실이 발생하고, UV 살균의 경우 UV에 의한 사용관리자의 위험 및 장비의 광부식 문제, O₃ 의 경우 고압전류 사용에 따른 위험성 등의 한계점이 나타나고 있다. 지하수 수질정화를 위한 광유도 활성산소(¹O₂, ·O^-₂)는 광감응제에 가시광의 빛 조사를 통해 생성되는 활성산소로의 에너지 및 전자 전이가 동시 진행되어 단일항 산소(¹O₂)와 슈퍼옥사이드 이온(·O^-₂)을 생성하게 된다. 생성된 활성산소는 유해미생물 또는 유기화학물과 개열, 제거, 치환 반응 등을 통해 미생물사멸 및 유해화학물질들이 분해 가능하다. 이를 이용한 지하수 유해미생물 사멸기술, 장비, 실시간 지하수의 분석기술 및 정수처리, 지하수 물순환 시스템 개발뿐만 아니라 지하수 음용수 및 오염개선, 지하수 기저유출에 의한 오염원 저감으로부터 지류·지천, 하천 본류 수질개선 등의 대상지역에 활용 가능하다. 또한 광유도 활성산소는 기존 상수도 수처리에 있어 오존(O₃) 처리와 이산화티탄을 이용한 AOP과정을 단일처리 공정으로, 기존 O₃ 의 특성상 확산 거리가 매우 길어 사람을 포함한 생체 내에 유입 시 다양한 부작용 발생과 O₃ 차폐시설 요구의 문제점 극복의 대안으로 환경 및 인체에 무해한 광유도 활성산소 시스템을 적극적으로 도입 및 적용해야 한다. 본 연구 목적은 정류상태 흡광분광기술을 이용한 실시간 수질 모니터링과 광유도 활성산소를 이용한 유해 미생물의 멸균효능 및 지하수 수질관리 기술로의 적용 가능성을 제시하고자 한다.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.8
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• pp.355-364
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• 2023

As advanced cyber threats continue to increase in recent years, it is difficult to detect new types of cyber attacks with existing pattern or signature-based intrusion detection method. Therefore, research on anomaly detection methods using data learning-based artificial intelligence technology is increasing. In addition, supervised learning-based anomaly detection methods are difficult to use in real environments because they require sufficient labeled data for learning. Research on an unsupervised learning-based method that learns from normal data and detects an anomaly by finding a pattern in the data itself has been actively conducted. Therefore, this study aims to extract a latent vector that preserves useful sequence information from sequence log data and develop an anomaly detection learning model using the extracted latent vector. Word2Vec was used to create a dense vector representation corresponding to the characteristics of each sequence, and an unsupervised autoencoder was developed to extract latent vectors from sequence data expressed as dense vectors. The developed autoencoder model is a recurrent neural network GRU (Gated Recurrent Unit) based denoising autoencoder suitable for sequence data, a one-dimensional convolutional neural network-based autoencoder to solve the limited short-term memory problem that GRU can have, and an autoencoder combining GRU and one-dimensional convolution was used. The data used in the experiment is time-series-based NGIDS (Next Generation IDS Dataset) data, and as a result of the experiment, an autoencoder that combines GRU and one-dimensional convolution is better than a model using a GRU-based autoencoder or a one-dimensional convolution-based autoencoder. It was efficient in terms of learning time for extracting useful latent patterns from training data, and showed stable performance with smaller fluctuations in anomaly detection performance.

• Journal of Korean Home Economics Education Association
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• v.34 no.4
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• pp.113-129
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• 2022

The purpose of this study is to propose implications by analyzing the textiles and clothing curriculum of vocational high schools. Literature and data were analyzed, surveys and FGI were conducted, and the following research results were derived. First, many schools chose 'Basic dress design' or 'Basic dress composition' as basic subjects. Through this, it was confirmed that technical training for practice is a priority for vocational schools, and that more discussion is needed regarding the lack of theoretical subjects. Second, similarly to the basic subjects, practical subjects offered are concentrated on 2 to 3 subjects. The teachers asserted that some subjects such as 'Knit apparel production' and the 'Leather and fur design production', which require a lot of equipment and advanced technology, cannot be offered without support from the government. Third, the NCS competency unit of the practical subjects is easy to proceed with the class or is closely concentrated on the type of manpower training presented by each department. Fourth, this study proposes that for technical education to expand students' choice, it is necessary to cultivate teachers competencies linked to the industry. The results of this study are expected to provide basic data on the organization of the next textiles and clothing professional curriculum and help understand vocational education at vocational high schools. In addition, it is believed that this study will contribute to developing and settling various subjects when the high school credit system is implemented by expanding students' choice of major-related subjects.

• Journal of Advanced Navigation Technology
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• v.27 no.3
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• pp.306-313
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• 2023

Realistic and graphics-based virtual reality content is based on 360-degree videos, and viewport extraction through the viewer's intention or automatic recommendation function is essential. This paper designs a viewport extraction system based on multiple object tracking in 360-degree videos and proposes a parallel computing structure necessary for multiple viewport extraction. The viewport extraction process in 360-degree videos is parallelized by composing pixel-wise threads, through 3D spherical surface coordinate transformation from ERP coordinates and 2D coordinate transformation of 3D spherical surface coordinates within the viewport. The proposed structure evaluated the computation time for up to 30 viewport extraction processes in aerial 360-degree video sequences and confirmed up to 5240 times acceleration compared to the CPU-based computation time proportional to the number of viewports. When using high-speed I/O or memory buffers that can reduce ERP frame I/O time, viewport extraction time can be further accelerated by 7.82 times. The proposed parallelized viewport extraction structure can be applied to simultaneous multi-access services for 360-degree videos or virtual reality contents and video summarization services for individual users.

• Journal of International Area Studies (JIAS)
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• v.15 no.1
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• pp.31-60
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• 2011

Medvedev administration has adopted new foreign policy line because of Obama administration's 'Reset' policy and Global economic crisis. The objectives of Medvedev's new foreign policy are the creation of a favorable external environment and the efficient use of external resources for Russia's economic modernization. To achieve these goals, Medvedev's government fleshed out such specific action plans as the avoidance of conflicts with other powers, the prevention of conflicts around Russia's borders, the activation of capital investment, and the introduction of advanced technology from the outside. This foreign policy line takes shape in the building of a foundation for strategic cooperation with the United States, the preparation for 'Modernization Alliance' with Europe, the management of cooperation and conflict with China and Japan, and the introduction of a dual strategy of strategic stability and economic integration in relations with post-soviet states. In Russia's new foreign policy line the strengthening of relations with the United States and Europe acquires highest priority. However, this does not mean a return to a 'pro-Western liberal line' in the early 1990s. The ultimate goal of Russia's 'modernization' program still lies in the rebuilding of a powerful Russia in accordance with the multipolar world order that was Putin administration's foreign policy line. In this context, foreign policy change under Medvedev administration could be defined as a 'program change at international level' that signifies a change in the means to achieve goals without changing them.

• Korean Journal of Acupuncture
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• v.40 no.3
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• pp.79-89
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• 2023

Objectives : The purpose of this study is to investigate various application methods of focused ultrasound and apply them to clinical use in Korean medicine. Methods : Search was performed using the search engines of electronic databases, including PubMed, ScienceDirect, Cumulative Index to Nursing and Allied Health Literature (CINAHL), ScienceON, Oriental Medicine Advanced Searching Integrated System (OASIS), China National Knowledge Infrastructure (CNKI), Wanfang Data, Japan Science Technology Information Aggregator, Electronic (J-STAGE) and Citation Information by NII (CiNii), from inception to July 2023 without language limitation. Inclusion criteria were clinical studies including randomized controlled trials (RCTs), and animal experimental studies related with focused ultrasound treatments for acupoints or meridian sinews. Results : Total 17 papers, 7 for RCT, 6 for in vivo animal studies, and other experimental studies, were finally selected. Indications used in studies were shoulder pain, back pain, chronic back pain, and degenerative knee arthritis. In experimental studies, studies on animal models of hypoxic ischemic brain damage and hyperlipidemia were also conducted. As for the acupoints, LR3, LI4, and ST36 were used in clinical studies and, in animal experimental studies, GV20, KI1, and ST36 were used. As for the dose, 4 studies below 3 W/cm² and 3 studies in the range of 0.625 to 5 W/cm² in clinical studies, and all studies did not exceed 5 W/cm². In animal experimental studies, 0.5 W/cm², 2 W/cm², 7.5 WW/cm², 15 W/cm², 10~20 W/cm² were used. In all three studies describing the penetration depth during irradiation, it was less than 1 cm. Conclusions : We suggest that focused ultrasound is an appropriate treatment tool for stimulating the acupoints to transfer heat energy. Future studies with rigorous and well-designed RCTs for various diseases will be required to ascertain the focused ultrasound stimulate acupoints or meridian sinews.