• Tunnel and Underground Space
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• v.19 no.4
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• pp.318-327
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• 2009

Accelerated weathering tests was executed to understand the physical characteristics of rocks in Dokdo. For the tests rock samples including trachytic andestes, andesite dyke and ash tuff were taken in place. Double soxhlet extractor and peristatic pump were used for accelerating the weathering processes. After the tests for 4 months, the variations of superficial structure, microscopic structure and strength of rock samples were observed.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.3
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• pp.155-158
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• 2006

$SF_6$ gas circuit breakers we widely used for short circuit current interruption in EHV or UHV power system. For a $SF_6$ gas circuit breaker development, the hot gas velocity measurement is necessary during $SF_6$ gas circuit breaker's trip operation. Small-gap flashover characteristics are used for this hot gas velocity measurement. This study sho was the hot gas velocity measurement results during $SF_6$ gas circuit breaker' trip operation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.10
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• pp.528-533
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• 2006

To analyze the small current interruption performance for the gas circuit breakers, the gas density and electric field intensity should be calculated. In this paper, the FVFLIC method is used for the gas flow analysis and the FEM for the electric field analysis. Then, the dielectric withstanding voltage is evaluated by the empirical formulation or Streamer theory. By comparing the calculated dielectric strength with the test result, it is found that both methods show good prediction capability for the small current interruption performance. Especially, when both methods predict the same interrupting performance, the prediction is in accordance with the experimental result.

• Proceedings of the KIEE Conference
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• 2005.11c
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• pp.90-92
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• 2005

When the jacket damaged conductors in 22.9kV-y overhead distribution lines are contacted with the metal material by strong wind, which, leads to are melting as well as faults accordance. The duration of the arc temperature due to flame effected by weather and flash over conditions. In order to simulated the worst conditions, the ACSR-OC($58mm^2$) used as specimen was artificially cut in no wind. After contacting the two cut conductors again the testing current was applied. thus, the changes in temperature of are flame was analyzed.

• Journal of Biomedical Engineering Research
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• v.26 no.1
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• pp.31-35
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• 2005

A novel synthetic aperture method for real-time three-way dynamic focusing is proposed, which provides lateral beam patterns represented as the product of Fourier transforms of transmit subaperture, receive subaperture, and a synthetic window function. In the proposed method, all array elements are fired individually and for each firing echo signals are recorded from all elements of a receive subaperture moving along an array with the transmit element. The three-way dynamic focusing is then achieved by employing a synthetic aperture algorithm for two-way dynamic focusing and a synthetic focusing method for transmit dynamic focusing. Both theoretical analysis and computer simulation results show that the proposed method produces ultrasound beams with improved lateral resolution at all depths compared to the conventional phased array imaging and synthetic aperture focusing methods.

• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.333-334
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• 2010

본 논문에서는 풍력발전기용 전력변환기의 소자에서 발생하는 열을 효율적으로 냉각시키기 위한 수냉식 방열판의 구조를 제안한다. 인버터 IGBT의 방열을 위한 방열판의 구조는 전체 stack의 방열시스템에서 중요한 부분을 차지하며, 인버터 시스템의 전력밀도 향상을 위해서 시스템 내부 구조가 콤팩트 해야하기 때문에 방열판에 대한 설계 및 방열구조 설계의 연구는 필수적이라 할 수 있다. 본 논문에서는 발열원을 기준으로 수로의 숫자와 형태변화를 통해 방열현상을 CosmosFloXpress를 통해 해석하여 방열효과가 우수한 방열판을 선정하였다. 추후 시뮬레이션 결과를 토대로 배관구조를 적용한 전력변환기의 제작 및 실험을 통해 제안된 모델의 타당성을 검증하고자 한다.

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.32-32
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• 1997

The regulatory role of A$\sub$2A/ adenosine receptors in P$_2$ purinoceptor-mediated calcium signaling was investigated in rat pheochromocytoma (PC12) cells. When PC12 cells were treated with 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS21680), a specific agonist of the A$\sub$2A/ adenosine receptor, extracellular ATP-evoked [(CA$\^$2+/)]$\sub$i/ rise was inhibited by 20%.(omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.414.1-414.1
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• 2002

To improve the compliance of oral administration of drugs in cancer patients, who are unable to swallow tablets, FDT containing ondansetron HCI($Onseran^{TM}$) was developed with a low-cost manufacturing process. $Onseran^{TM}$ was prepared from ondansetron. mannitol, crospovidone. and others with a direct compression method. The disintegration time and dissolution rate of $Onseran^{TM}$ were assessed according to the USP method. The results were compared with those of the reference drug ($Zofran^{TM}$). (omitted)

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.420-423
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• 2020

As a result of continuous taxonomic studies on the Korean crabs, Carcinus aestuarii Nardo, 1847 belonging to the superfamily Portunoidea is newly reported from Korean waters. Carcinus aestuarii has characteristics as followings: cardiac, hepartic and brachial regions are divided by deep furrow; shape of three lobes in frontal area is flatter with hairy; inside of carpus is with one sharp tooth; the posterior-lateral margin of the carapace is concave, and so on. The examined specimen doesn't have hairy and bump on outer margin of the chelipeds which differed from the previous description of the specimens collected from Tokyo Bay, Japan. Here, the diagnosis and the picture of Korean specimen is provided. Korean portunoids currently consist of 20 species belonging to 10 genera.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.1041-1043
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• 2022

항만 안전사고를 줄이고자 하는 노력에도 불구하고 항만 산재는 지속적으로 발생하고 있으며, 2017년이후 지속적으로 증가하는 추세이다. 이는 근속 기간이 적어 충분한 훈련이 되지 않았거나 근로자의 안전보다 작업의 효율성이나 비용을 더 우선시하는 환경, 컨트롤 타워의 부재 등으로 인해 발생하는 것으로 추정된다. 본 프로그램에서는 안전사고 관리 기능을 통해 항만 산재를 체계적으로 관리하여 개선된 작업 환경을 제공하고, 훈련 알고리즘을 통해 근로자의 항만 사고를 효과적으로 예방하고자 한다.