• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.640-645
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• 2001

The present study is to investigate the characteristics of the impulse waves discharged from the exit of the convergent and divergent pipes. An experiment is carried out using a shock tube with an open end and is compared to the computation of the axisymmetric, compressible, unsteady Euler equations, which are solved by the second-order total variation diminishing(TVD) scheme. For the computational work, some initial compression waves are assumed inside the pipe so that those are identical to the experimental ones of the shock tube. The results show that the peak pressures of the impulse waves discharged from the exit of convergent and divergent pipes decrease with an increase in the wavelength of the initial compression wave. All of the impulse waves have a strong directivity toward the pipe axis, regardless of the exit type of the pipe employed. The impulse waves discharged from the divergent pipe are stronger than those from the straight pipe, while the impulse waves of the convergent pipe are weaker than those from the straight pipe. It is believed that the convergent pipe can playa role of a passive control to reduce the peak pressure of the impulse wave. The present computations represent the experimented impulse waves with a good accuracy.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.177-184
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• 2012

A hologram projects a 3 dimensional video as same as a real subject and it is made by principles of holography. Many researches about holographic technology have been developed. Studies for visualization of 3D videos, holographic storages, and optical media have proceeded mostly in engineering. It is hard to find any researches about the convergent system from the viewpoint of interactive elements and motion graphic design such as this paper's concept. Most studies of augmented reality have been developed in the domain of technology and education but the field of content production. AR has been convergent with various fields and media, so it is time to make an active progress in the study of convergent content development. The goal of this study is to develop cultural contents and create new values through the convergence of holography and AR. The purpose of this paper is to propose the way of developing the convergent type of cultural contents and construct the production system by the new approach to users using the convergence technology of holography and augmented reality.

• 한국측량학회지
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• 제3권2호
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• pp.39-47
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• 1985

본 연구는 직선 및 원호상에서 얻은 지상수렴사진의 space resection, space intersection을 공선조건에 의해 해석함으로써 그의 특성을 구명하고 최적수렴각의 범위를 제시하는 데 목적이 있다. 수렴각의 변화에 따른 정확도는 20$^\circ$미만에서는 오히려 직각수평사진보다 떨어지나 20$^\circ$이상 증가함에 따라 향상되어 90$^\circ$의 수렴각에서 가장 현저한 향상을 나타낸다. 또한 원호상수렴사진이 직선상수렴사진에 비하여 현저히 향상된 정확도를 가져오므로 각종 시설물의 정밀해석에 이의 활용이 기대된다.

• International Journal of Aeronautical and Space Sciences
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• 제18권3호
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• pp.395-402
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• 2017

The local heat transfer and total pressure drops of developed turbulent flows in the ribbed rectangular convergent/divergent channels with ${\Lambda}/V-shaped$ ribs have been investigated experimentally. The channels have the exit hydraulic diameter ($D_{ho}$) to inlet hydraulic diameter ($D_{hi}$) ratios of 0.67 for convergence and 1.49 for divergence, respectively. The ${\Lambda}/V-shaped$ ribs with three different flow attack angles of $30^{\circ}$, $45^{\circ}$, and $60^{\circ}$ are manufactured with a fixed rib height (e) of 10 mm and the ratio of rib spacing (S) to height (e) of 10 on the walls. Thermal performances of the ribbed rectangular convergent/divergent channels are compared with the smooth straight tube under identical pumping power. The results show that the flow attack angle of $45^{\circ}$ with ${\Lambda}-shaped$ rib has the greatest thermal performance at all the Reynolds numbers studied in the convergent channel; whereas, the flow attack angle of $60^{\circ}$ with V-shaped rib has the greatest thermal performance over Reynolds number of 30,000 in the divergent channel.

• Journal of Microbiology and Biotechnology
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• 제33권8호
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• pp.981-991
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• 2023

Monkeypox (Mpox) virus, a member of the Poxviridae family, causes a severe illness similar to smallpox, which is characterized by symptoms such as high fever, rash, and pustules. Human-to-human transmission cases have been reported but remained low since the first recorded case of human infection occurred in the Congo in 1970. Recently, Mpox has re-emerged, leading to an alarming surge in infections worldwide since 2022, originating in the United Kingdom. Consequently, the World Health Organization (WHO) officially declared the '2022-23 Mpox outbreak'. Currently, no specific therapy or vaccine is available for Mpox. Therefore, patients infected with Mpox are treated using conventional therapies developed for smallpox. However, the vaccines developed for smallpox have demonstrated only partial efficacy against Mpox, allowing viral transmission among humans. In this review, we discuss the current epidemiology of the ongoing Mpox outbreak and provide an update on the progress made in diagnosis, treatment, and development of vaccines for Mpox.

• Journal of applied mathematics & informatics
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• 제28권3_4호
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• pp.823-835
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• 2010

In this paper, A FSQP algorithm for degenerate inequality constraints optimization problems is proposed. At each iteration of the proposed algorithm, a feasible direction of descent is obtained by solving a quadratic programming subproblem. To overcome the Maratos effect, a higher-order correction direction is obtained by solving another quadratic programming subproblem. The algorithm is proved to be globally convergent and superlinearly convergent under some mild conditions. Finally, some preliminary numerical results are reported.

• Kyungpook Mathematical Journal
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• 제52권2호
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• pp.189-200
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• 2012

In this article we introduce the class of I-convergent double sequences of fuzzy real numbers. We have studied different properties like solidness, symmetricity, monotone, sequence algebra etc. We prove that the class of I-convergent double sequences of fuzzy real numbers is a complete metric spaces.

• 한국위성정보통신학회논문지
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• 제4권2호
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• pp.1-4
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• 2009

본 논문에서는 우주기술과 정보기술 융합이 단순한 화두가 아니라 우리나라 신성장동력 엔진의 키워드로 자리매김 할 수 있도록 ST-IT 융합기술이 무엇이고, 우리나라의 ST 및 IT 기술현황을 소개한다. 향후 ST-IT 융합기술의 발달에 따라 기술 및 산업 간의 벽이 허물어지고 새로운 가치와 시장이 창출되는 등 역동적인 변화가 예상되기 때문에 향후 ST-IT 융합기술 발전 방향을 제시하고자 한다.

• 한국전기전자재료학회논문지
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• 제20권5호
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• pp.467-470
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• 2007

Application field of neutron beam is very broad including industry, medicine and science. But the research and development and use of neutron beam is restricted within in narrow limits in this country, because neutron beam facility is insufficient - a big research facility of nuclear reactor(HANARO) and some small industrial facilities which use radioisotope neutron source are available. This paper compare and investigate the results of experiment and numerical analysis of the discharge in the spherically convergent beam fusion device which were expected as a portable neutron source. The spherically convergent beam fusion device will offer stability in neutron production, possibility of movement for convenience, low construction cost and higher neutron flux than radioisotope neutron source. The star mode discharge which efficiently generate neutron, were observed at both results.

• 한국멀티미디어학회논문지
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• 제17권11호
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• pp.1354-1362
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• 2014

In order to solve the complicated problems faced by the spread of diversified information devices and changes in the user environment in recent years, the importance of training creative talent as well as the need for interdisciplinary convergent approach have emerged. As a future technology development project, convergence education with the design sector for training creative talent in the IT field is also urgent. In this study, we recognized the importance and problems of the convergent approach between IT and design sector by examining the convergence theory and cases with a focus on effective creativity development and sought a new direction for convergence education in the future by investigating the awareness on the convergent approach of college students and analyzing the results. This will be able to have significance as a basic study for discovering creative and innovative convergent talent in the IT and design sector in the future and strengthening basic competence.