• Structural Engineering and Mechanics
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• 제64권1호
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• pp.81-92
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• 2017

Many materials in engineering exhibit different modulus in tension and compression, which are known as bi-modulus materials. Based on the bi-modulus elastic theory, a modified semi-analytical model, by introducing a stress function, is established in this paper to study the mechanical response of a bi-modulus cylinder placed in an axisymmetric temperature field. Meanwhile, a numerical procedure to calculate the temperature stresses in bi-modulus structures is developed. It is proved that the bi-modulus solution can be degenerated to the classical same modulus solution, and is in great accordance with the solutions calculated by the semi-analytical model proposed by Kamiya (1977) and the numerical solutions calculated both by the procedure complied in this paper and by the finite element software ABAQUS, which demonstrates that the semi-analytical model and the numerical procedure are accurate and reliable. The result shows that the modified semi-analytical model simplifies the calculation process and improves the speed of computation. And the numerical procedure simplifies the modeling process and can be extended to study the stress field of bi-modulus structures with complex geometry and boundary conditions. Besides, the necessity to introduce the bi-modulus theory is discussed and some suggestions for the qualitative analysis and the quantitative calculation of such structure are proposed.

• 한국농공학회논문집
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• 제65권1호
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• pp.61-72
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• 2023

The increase in the rearing intensity of pigs has caused deterioration in the pig house's internal environment such as temperature, humidity, ammonia gas, and so on. Traditionally, the widely used method to control the internal environment was through the manipulation of the ventilation system. However, the conventional ventilation system had a limitation to control the internal environment, prevent livestock disease, save energy, and reduce odor emission. To overcome this problem, the air-recirculated ventilation system was suggested. This system has a semi-closed loop ventilation type. For designing this system, it was essential to evaluate the ventilation rates considering the pressure loss of ducts. Therefore, in this study, pressure loss calculation and experiment were conducted for the quantitative ventilation design of a semi-closed loop system. The results of the experiment showed that the inlet through which external air flows should always be opened. In addition, it was also found that for the optimum design of the semi-closed loop ventilation system, it was appropriate to install a damper or a backflow prevention device rather than a ventilation fan.

• 분석과학
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• 제33권4호
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• pp.197-207
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• 2020

The current comparison methods with scoring systems that are used to compare visualized latent fingerprints (LF) have disadvantages. Evaluators using these methods are prone to make errors and fail to discriminate LFs correctly to notice the differences among those LFs. Therefore, a comparative and quantitative evaluation method that is capable of obtaining more objective and quantitative results is needed. Densitometric image analysis (DIA) is used in other fields as a reliable semi-quantitative comparison method. To apply DIA to LFs, the potential variables that can occur during the DIA process were tested. The visualized ridges of LFs can be compared using the concentration of dots against the background to make it possible to analyze the ridges with DIA. The variables that can be present during the DIA process include the thickness of the analysis line, the number of ridges to be taken, the number of divided zones within each of the fingerprints, and the angles of the analysis line against the ridge lines that were selected. From the analysis of the inked fingerprints and circular lines that are similar to fingerprints, the angle of the analysis lines with the ridge line was the most significant variable. The preliminary test result was applied to the comparison of LFs that were developed with the powder method and then compared with the AFIS analysis. A similar trend was found, and a more detailed and semi-quantitative comparison of the visualized LFs was possible. In the future, it is necessary to check the evaluative ability of the DIA method by analyzing the visualized LFs with other various development methods. However, DIA is currently an option that can be used as an objective comparative evaluation method during fingerprint studies with supplementary role.

• 대한화장품학회지
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• 제39권4호
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• pp.281-288
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• 2013

히알루론산(HA)은 피부의 세포외기질을 구성하는 주성분이다. 인간의 피부에서 히알루론산의 양은 노화와 함께 감소되는 것으로 보고되어 있으며, 이것은 노화에 따른 피부 수분 감소, 주름 형성 및 피부 탄력 저하에 관여한다고 알려져 있다. 지금까지 밝혀진 히알루론산 합성효소(hyaluronan synthase, HAS)들 중에 HAS-2가 사람의 피부 섬유아세포에서의 히알루론산의 합성을 조절하는 것으로 알려져 있다. 본 연구에서는 천궁으로부터 분리된 ferulic acid가 사람의 피부 유래 섬유아세포에서 히알루론산의 생성에 미치는 효과를 확인하였다. Semi-quantitative RT-PCR과 quantitative real-time PCR을 통해 ferulic acid가 HAS-2의 발현을 증가시키는 것을 확인하였으며 ELISA assay를 통해 ferulic acid가 히알루론산의 생성을 증가시키는 것을 확인하였다. 결론적으로 본 연구를 통해 ferulic acid는 피부 노화에 따른 히알루론산의 감소에 의해 나타나는 건조, 주름 및 탄력 저하와 같은 현상을 개선시킬 가능성을 가진 물질임을 확인하였다.

• Macromolecular Research
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• 제17권10호
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• pp.807-812
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• 2009

In this work, we focus on the tumbling dynamics of rod-like and semi-flexible polymers in mixed flows, which vary from simple shear to pure rotation. By employing a bead-rod model, the tumbling pathways and periods are examined with a focus on the angular distribution of their orientation. Under the mixed flows, the tumbling dynamics agreed well with earlier studies and confirmed the predicted scaling laws. We found that the angular distribution deviates from that of shear flow as the flow type approaches pure rotation. Finally, we investigated the angular distribution of $\lambda$-DNA in a shear flow and found that the present numerical simulations were in quantitative agreement with the previous experimental data.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 2004년도 제56차 추계 학술대회 연제집
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• pp.44.2-44.2
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• 2004

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권10호
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• pp.3685-3707
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• 2021

In recent years, facial attribute editing has been successfully used to effectively change face images of various attributes based on generative adversarial networks and encoder-decoder models. However, existing models have a limitation in that they may change an unintended part in the process of changing an attribute or may generate an unnatural result. In this paper, we propose a model that improves the learning of the attention mask by adding a spatial attention mechanism based on the unified selective transfer network (referred to as STGAN) using semi-supervised learning. The proposed model can edit multiple attributes while preserving details independent of the attributes being edited. This study makes two main contributions to the literature. First, we propose an encoder-decoder model structure that learns and edits multiple facial attributes and suppresses distortion using an attention mask. Second, we define guide masks and propose a method and an objective function that use the guide masks for multiple facial attribute editing through semi-supervised learning. Through qualitative and quantitative evaluations of the experimental results, the proposed method was proven to yield improved results that preserve the image details by suppressing unintended changes than existing methods.

• 한국ITS학회 논문지
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• 제12권3호
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• pp.19-28
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• 2013

본 연구는 반감응 신호제어 적용에 따른 정량적인 효과를 현장에서 수집된 자료를 활용하여 평가하였다. 이를 위하여 지방부도로에 현장을 선정하여 반감응 신호제어 시스템을 대규모로 설치하였다. 또한 이러한 시스템을 현장에서 구현하기 위한 신호제어 전략을 개발하고, 표준제어기의 내부 기능을 수정하여 교차로에 구현하였다. 그리고 교통량, 통행시간, 지체차량수의 3가지 효과척도를 이용하여 효과를 제시하였다. 분석결과로부터, 반감응 신호제어시스템 적용시 주방향의 용량이 증대되어 오전 및 오후 첨두시 평균적으로 9.4%, 11.3%의 통과교통량 증가가 각각 나타났다. 그리고 직진 차량에 대한 녹색시간 폭이 확대되어 평균적인 주행시간이 오전 첨두시에는 6.3%, 오후 첨두시에는 7.8% 감소하였다. 지체차량의 수도 오전 첨두시에는 36.4%, 오후 첨두시에는 23.9% 감소되어 반감응 도입에 따른 제어 효과가 큰 것으로 확인되었다. 따라서 주도로와 부도로 교통량의 편차가 크고, 횡단보도 보행자가 적은 특성이 있는 도로에는 반감응제어가 매우 효과적인 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.378-381
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• 2001

Sulfamethazine has been widely used in swine for prevention or treatment of infections. Recently, the safety of the drug to consumers has been questioned because of carcinogenic effects. To prevent unwanted drug residues entering the human food chain, both government authorities and industries have established extensive control measures. The demands for reliable, simple, sensitive, rapid and low-cost methods for residue analysis of foods are increasing nowadays. In this study, we established a rapid prediction test for the detection of cattle with violative tissue residues of sulfamethazine. The recommended therapeutic dose of sulfamethazine (withdrawal time, 15 days) was administered to each of 10 cattle. Blood was sampled before drug administration and during the withdrawal period. The concentration of sulfamethazine in plasma, determined by a semi-quantitative ELISA, was compared to that of an internal standard (10 ppb). The absorbance ratio of internal standard to sample (B/Bs) was employed as an index to determine whether drug residues in cattle tissues were negative or positive. That is, a B/Bs ratio less than 1 was considered residue positive and if larger than 1 was considered negative. All 10 plasma samples from non-treated cattle showed negative to sulfamethazine. Sulfamethazine was detected in plasmas of treated cattle until Day 7 of withdrawal period. The present study showed that the semi-quantitative ELISA could be easily adapted in predicting residues of sulfamethazine in live cattle.

• 한국전자통신학회논문지
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• 제8권12호
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• pp.1905-1910
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• 2013

논문은 유도 루프식 열차제어시스템에 대하여 준 정량적 안전무결성 등급(Safety Integrity Level : SIL)할당 방법을 적용하여 안전무결성 등급을 할당한 결과이다. 유도 루프식 열차제어시스템은 ATS장치, 지상ATP장치, 차상ATP장치, 지상ATO장치, 차상ATO 지상장치 하드웨어 및 소프트웨어로 구성되어 있으며, 안전무결성 등급 할당은 각 서브시스템에 대한 안전무결성 등급을 의미한다. 준 정량적 방법의 세 원칙에 근거하여, 열차제어시스템을 구성하고 있는 서브시스템에 대한 안전무결성 등급을 할당하였다.