• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.355-358
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• 2005

지난 40여 년에 걸쳐 극초음속 비행시연 기술을 포함한 스크램제트 기술은 현저한 진보를 보였다. 특히 1990년대 이후 스크램제트 개발에 있어서 국제적인 활동이 눈에 띄게 증가한 점은 주목할 만하다. 선진국에서는 새로운 세대의 산업 및 군사적 능력을 위해서 현재 진행되고 있는 많은 연구 프로그램들을 통해 강력한 스크램제트 개발 능력이 구축되고 있다. 본 논문에서는 선진 각국의 스크램제트 개발 프로그램들을 살펴봄으로써 스크램제트 기술 현황을 제시하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.130-132
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• 1996

The squirrel cage rotors for induction motors may have several faults such as broken bars, bad spots in the end ring and abnormal skew caused by improper processing. These faults have bad effect on the performance of the induction motor. In this paper, these fault detection method is proposed, then the effects on the performance of the motor is analyzed using FEM.

• 대한기계학회논문집A
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• 제22권4호
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• pp.879-886
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• 1998

It is very important to understand the vibration and noise characteristics of a structure to developed quiet machines and lessen their noise. In this paper, the vibration and sound radiation characteristics of a simple and a bar-stiffened plate have been investigated using numerical and experimental techniques. In numerical process, FEM analysis has been performed for the vibration level ; the time-space squared and averaged velocity and BEM analysis for sound radiation parameters ; sound power and radiation efficiency. In experimental process, FFT signal processing method has been used. While a power from an exiciter is applied to the structure by using a point contact, sound intensity and vibration level has been measured. Based on these two data, the radiation efficiency has been calculated. Results show that the radiation efficiency for the stiffened structure increases compared to the simple plate, due to the extra edges provided by the stiffener.

• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.219-224
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• 2003

Structured lipid (SL) produced from soybean oil was enriched with conjugated linoleic acid (CLA). The SL had 21.9 mol % CLA isomers incorporated into SL-soybean after the 24-h reaction. Removal of tocopherols (73～84% loss from original soybean oil) was observed in the SL. Electronic nose can discriminate the aroma of SL-soybean from that of soybean oil. Many oxidative volatiles including pentenal, octenal, 2,4-decandienal, and nonenal were found in SL-soybean. Electronic nose, which is valuable for composite aroma analysis, can provide flavor information together with GC-MS that is useful for qualitative or quantitative analysis of each odor compound in SL.

• 동의생리병리학회지
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• 제21권5호
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• pp.1303-1306
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• 2007

Idiopathic thrombocytopenic purpura(ITP) is an autoimmune disease which is related to antibodies against platelets. More than 95% of the patients progress into chronic type. Usually, IPT patients suffer form hypodermal bleeding, purpura, decreases in platelet counts. Purpura of legs, nosebleeds and oral ulcer may occur. In this study, herbal medicine, acupuncture and moxibustion in conjunction with cupping were applied to IPT patient based on the oriental medicine principle such as Lihyulyanggangeonbi-tang(理血養肝建脾湯). After the treatment, the patient improved better, and had no more inconvenient symptoms according to the follow-up research. So the result shows the possibility that oriental medical treatment may be applied to the IPT patient clinically.

• 한국연소학회지
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• 제4권1호
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• pp.131-139
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• 1999

A Numerical Analysis of NOx production in Hydrogen-Air flame is performed using the quasi-laminar reaction modelling. As results, in low global strain rate region, $U_F/D_F\;{\leq}\;50,000$, the quasi-laminar reaction modelling reproduces the experimentally observed EINOx half power scaling that the ratio of EINOx and flame residence time, $L_f^3(D_F^2U_F)$, is proportional to the square root of global strain rate. Thus, it suggests that turbulence-chemistry interaction has a minor impact on the trend of NOx production in low global strain rate region. However, the quasi-laminar reaction modelling predicts the higher temperature and NOx than experimentally observed. This overprediction may be due to the lack of radiation and quasi-laminar reaction modelling.

• 한국정밀공학회지
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• 제23권6호
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• pp.160-165
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• 2006

We have designed a high-transmission nano aperture in a perfect electric conductor film with the incident beam of 532 nm wavelength. The aperture basically has a C-shape and is known to produce a bright spot nearby the aperture in small size less than diffraction limit. The bright spot is strongly coupled with the local plasmon excited through the aperture hole. The characteristics of transmission and peak power of the aperture output were calculated using finite differential time domain (FDTD) technique, and the geometry of the aperture was determined to get a maximum transmission and peak power. To find the effect of the surface plasmon induced near by the aperture, we calculated the variations of the transmittance and the beam sizes by changing the size of the input beam irradiated on the aperture.

• 농촌계획
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• 제12권2호
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• pp.1-9
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• 2006

Current environmental problems of rural area are connected to loss of rural functions which is food security as well as conservation of environment, balanced development of country and succession of traditional culture. To solve these problems, recent projects are focusing on social changes in rural area and conservation of rurality creating values of rural amenity resources. At this point, full implications of rurality which is the various aspects of rurality should be defined to be applied in direct plans to conserve the rurality. In this study, nine attributes of rurality are found as various meanings with adjectives included in image of rurality. For practical use of these adjectives of rurality attributes, we evaluate the list of rural amenity resources and suggested plans for conservation of rural amenity. These attributes can be used as an effective method for village plan which brings one of the attributes into relief.

• Communications for Statistical Applications and Methods
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• 제7권2호
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• pp.513-523
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• 2000

The X-12-ARIMA program was utilized on the analysis of the time series trend on 76 Korean industrial activities data in order to ensure that the trading day effect adjustment as well as the seasonal effect adjustment is needed to extract the fundamental trend-cycle factors from various economic time series data. The trading day effect is strongly correlated with the activity of production and shipping but not with the activity of inventory. Furthermore, the industrial activities were classified with respect to the sensitivity on the tranding day effect.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2001년도 춘계 학술대회논문집
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• pp.149-154
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• 2001

Parallel performance of a Myrinet based PC-cluster was tested and compared with a conventional Fast-Ethernet system. A preconditioned Navier-Stokes code was parallelized with domain decomposition technique, and used for the parallel performance test. Speed-up ratio was examined as a major performance parameter depending on the number of processor and the network topology. As was expected, Myrinet system shows a superior parallel performance to the Fast-Ethernet system even with a single network adpater for a dual processor SMP machine. A test for the dependency on problem size also shows that network communication speed is a crucial factor for parallelized computational fluid dynamics analysis and the Myrinet system is a plausible candidate for high performance parallel computing system.