• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2010년도 춘계학술대회
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• pp.254-261
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• 2010

The increase in hazard level is attributed to the industrial hazard environment; complete national environmental hazards to human health include climate change. The damage level in Korea from 1993 to 2009 has exceeded the Increase In adverse environmental conditions. Priority areas of concern will include those risks that are most likely to occur and are expensive when they do take place such as accident or injury at a community pool. Therefore, in this paper, we suggest the System Engineering method for application to the railway RAMS. Recently, the requirement of high-integrity level of infrastructure has been deemed important. The systems level approach is defined through the assessment of the RAMS interactions between elements of complex system applications.

• 한국대기환경학회지
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• 제12권3호
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• pp.243-254
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• 1996

The main purpose of this study is to investigate the collection efficiency characteristics of a cylindrical ESP. To do that, it is necessary to analyze the electric field, gas flow field, and mechanism of particle movement by numerical simulation based on EHD model. For a gas flow field, Navier-Stokes equation involving the electric source term was solved by SIMPLE algorithm. In case of the electric field, the current continuity and electric field equations were solved by S.O.R. method. The analysis of particle movement was performed on the basis of PSI-CELL model from the Lagrangian viewpoint. The results showed that the influence on the gas flow field by the electric field is almost negligible in a cylindrical ESP. The particle drift velocity $V_P$ toward the collection surface is increased continuously by the electrostatic force due to the rise of particle charge as the particle is moving to the flow direction and the particle size becomes larger. The collection efficiency is to quitely higher with the increase of applied voltage for the same particle size, while becomes smaller as the inlet velocity is increased.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권9호
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• pp.676-680
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• 1999

To do breath alcohol measurement, a sensor is necessary that it can detect low alcohol gas concentration of 0.01% at least. In this work, a capacitance-type alcohol gas sensor using porous silicon layer is developed to measure low alcohol gas concentration. The sensor using porous silicon layer has some sensitivity at room temperature by very large effective surface area, but there is still much room for improvement. In this experiment, we measured the capacitance of the sensor under 254 nm UV light on the porous silicon layer, in which alcohol solution was kept in a flask at 25, 35, and $45^{\circ}C$ by a heater. As the result, the improvement of sensitivity by illuminating UV light was observed. The increasing rate of the capacitance was shown to be double more than those measured under UV-off state. It is supposed that UV light activates response of the oriental and interfacial polarizations which have slow relaxation time for AC field.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.248-254
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• 2012

During the monolayer assembly of zeolite microcrystals using sonication with stacking (SS) method, the factors that govern the degree of close packing (DCP) between the microcrystals, the rate of attachment (rA) of microcrystals onto the substrate, the degree of coverage (DOC), and the binding strength (BS) between each crystal and the substrate were investigated for each mode of binding linkage (MBL). The tested MBLs were covalent linkage (CL), ionic linkage (IL), and polyelectrolyte-mediated ionic linkage (p-IL). Unlike the monolayers of zeolite crystals assembled on glass with a covalent linkage, the strong BS, very high DOC, and very high DCP do not decrease during monolayer assembly on glass through ionic linkages. This results indicate that the surface migration of crystals undergo linkage-nondestructively when crystals were attached to the substrates through ionic linkages.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2010년도 춘계학술대회
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• pp.248-254
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• 2010

우리나라는 1960년대 이후 급격한 산업화로 인해 도시의 구조가 변화하기 시작하였으며 2004년 이후부터 대두된 유비쿼터스 도시(U-City)는 사회 각 분야에서 논의가 본격화되고 있다. U-City는 언제 어디서나 도시의 경쟁력과 삶의 질을 향상하기 위해 유비쿼터스기술을 도입한 도시 내 서비스가 제공되는 것이며 현재 우리나라의 U-City는 체계적인 서비스 도출 방법이 미흡한 실정이다. 이러한 문제점을 바탕으로 본 연구에서는 4개의 특징적인 가로를 대상으로 U-서비스를 비교 분석하여 향후 체계적인 서비스 도출 방안과 지속적인 서비스 운영 방안, 이용자 중심의 서비스 도출 방안에 대해 기본방향을 제시하고자 한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.254-257
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• 2004

In shallow water, the performance of the operating active sonar systems is usually limited by reverberation. One of the measure to overcome the negative effect of reverberation is of selecting an adequate transmission pulse. SFM(Sinusoidal Frequency Modulation) pulse has been received a considerable attention as a candidate for suppressing the reverberation effect. In this paper, we analyze the detection performance of SFM pulse with respect to modulation frequency and bandwidth. To conduct the analysis. we synthesize the signal at the receiver considering. the transmitter. the receiver, and the propagation medium characteristcs. The simulations provide the optimum modulation frequency and bandwidth under the given situation.

• Molecules and Cells
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• 제22권3호
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• pp.254-261
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• 2006

DNA microarray is a powerful tool for high-throughput analysis of biological systems. Various computational tools have been created to facilitate the analysis of the large volume of data produced in DNA microarray experiments. Normalization is a critical step for obtaining data that are reliable and usable for subsequent analysis such as identification of differentially expressed genes and clustering. A variety of normalization methods have been proposed over the past few years, but no methods are still perfect. Various assumptions are often taken in the process of normalization. Therefore, the knowledge of underlying assumption and principle of normalization would be helpful for the correct analysis of microarray data. We present a review of normalization techniques from single-labeled platforms such as the Affymetrix GeneChip array to dual-labeled platforms like spotted array focusing on their principles and assumptions.

• Structural Monitoring and Maintenance
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• 제6권3호
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• pp.237-254
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• 2019

This paper presents an improved time series based damage detection approach with experimental verifications for detection, localization, and quantification of damage in shear-type structures under varying mass effects using output-only vibration data. The proposed method can be very effective for automated monitoring of buildings to develop proactive maintenance strategies. In this method, Auto-Regressive Moving Average models with eXogenous inputs (ARMAX) are built to represent the dynamic relationship of different sensor clusters. The damage features are extracted based on the relative difference of the ARMAX model coefficients to identify the existence, location and severity of damage of stiffness and mass separately. The results from a laboratory-scale shear type structure show that different damage scenarios are revealed successfully using the approach. At the end of this paper, the methodology limitations are also discussed, especially when simultaneous occurrence of mass and stiffness damage at multiple locations.

• 식물분류학회지
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• 제52권4호
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• pp.251-254
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• 2022

Saxifraga cortusifolia Siebold & Zucc. (Saxifragaceae, sect. Irregulares, ser. Rufescentes), a species considered endemic along mountain streams throughout Honshu, Shikoku, and Kyushu in Japan, was discovered as a wild population in the Cheona Valley in Haean-dong, Jeju-si on Jeju-do Island of Korea. The population consisted of three subpopulations occupying narrow areas 10 × 10 m², 5 × 5 m², and 10 × 5 m² in size. The number of individuals in the three subpopulations was confirmed to exceed 100. Most of the individuals were on or below rocks at the edge of the valley. A morphological description, detailed photos, and a key to related taxa in Korea are presented.

• 한국환경농학회지
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• 제33권4호
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• pp.254-261
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• 2014

홍고추 생산을 위해 논 시설재배지의 토양화학성을 개선하고 생산성에 미치는 영향을 조사하기 위해 고추 정식 전에 규산질비료를 0, 100, 200, 300 kg/10a를 처리하였다. $N-P_2O_5-K_2O$는 토양검정에 의해 밑거름으로 질소 50%, 인산 100%, 칼리 60%을 시비한 후, 천하대세 품종을 $120{\times}45cm$ 간격으로 정식하고, 웃거름은 1, 2, 4차 수확 후 3회에 나누어 질소와 칼리를 시비하였다. 최종 5차 수확기에 조사한 토양 pH, 유효인산, 치환성 $Ca^{2+}$은 규산질비료 처리량에 따라 증가하였고, EC는 감소하였다. 유기물함량은 대조구보다 높았고, 치환성 $K^+$은 100과 200 kg/10a, $Mg^{2+}$는 300 kg/10a 처리구에서 높았다. 규산질비료가 정식 60일까지 지상부 생육에 미치는 영향은 적었다. 고추 1차 수확기 잎에 함유되어 있는 N과 P는 규산질비료 처리량과 반비례 관계였고, K. Ca, Mg은 300 kg/10a 처리구에서 가장 많았다. 홍고추 수량은 대조구에 비해 규산질비료 처리구에서 9.0~11.8% 증가하였고, 200 kg/10a 처리구에서 상품과율이 97.3%로 가장 높았고, 비상품과는 105 kg, FW/10a 수준으로 가장 낮았다. 규산질비료 시비량과 건고추수량의 관계식($Y=-0.0022X^2+0.827X+645.7$, $R^2=0.9838$)에 따른 최고수량은 723.4 kg/10a, 이때 규산질비료 시비량은 187.9 kg/10a 이었다. 이상의 결과에서 보는 바와 같이 답전윤환 시설재배지에 규산질비료를 밑거름으로 사용하면 토양화학성이 개선되고, 비상품과 수량이 감소하고 생산량이 증가하였다.