• Wind and Structures
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• 제28권3호
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• pp.155-170
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• 2019

This paper presents a novel test method for the galloping of iced conductor using wind generated by a moving vehicle which can produce relative wind field. The theoretical formula of transiting test is developed based on theoretical derivation and field test. The test devices of transiting test method for aerodynamic coefficient and galloping of an iced conductor are designed and assembled, respectively. The test method is then used to measure the aerodynamic coefficient and galloping of iced conductor which has been performed in the relevant literatures. Experimental results reveal that the theoretical formula of transiting test method for aerodynamic coefficient of iced conductor is accurate. Moreover, the driving wind speed measured by Pitot tube pressure sensors, as well as the lift and drag forces measured by dynamometer in the transiting test are stable and accurate. Vehicle vibration slightly influences the aerodynamic coefficients of the transiting test during driving in ideal conditions. Results of transiting test show that the tendencies of the aerodynamic coefficient curve are generally consistent with those of the wind tunnel tests in related studies. Meanwhile, the galloping is fairly consistent with that obtained through the wind tunnel test in the related literature. These studies validate the feasibility and effectiveness of the transiting test method. The present study on the transiting test method provides a novel testing method for research on the wind-resistance of iced conductor.

• KEPCO Journal on Electric Power and Energy
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• 제8권2호
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• pp.73-77
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• 2022

Recently, as the number of years of operation has increased for more than 30 years, interest in evaluating the remaining life of major power facilities such as transformers and ultra-high voltage cables is increasing. In particular, the risk of failure is increasing because the underground transmission XLPE cable has been built since 1980 and has been operating in excess of 30 years of design life or close proximity. Therefore, it is necessary to develop an algorithm to evaluate the residual life of the XLPE cable considering the load to determine the risk of failure. Since load data is large amount of data, it is necessary to make the variable load information equivalent to the time unit first in order to calculate the remaining life of the system quickly. In overseas literature, transformers are reported to be standardized for variable load equivalent conversion formulas, but they have not been reported for ultra-high voltage cables. Therefore, in this paper, whether the equivalent conversion formula of a transformer can be applied to XLPE cables was reviewed through accelerated degradation tests under equivalent and variable temperature conditions, and considerations were studied when evaluating the remaining operating life of XLPE cables based on the experimental results.

• 대한한의학방제학회지
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• 제30권3호
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• pp.205-210
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• 2022

Conventional pharmacology has followed the notion of the reductionist 'single target selective drug paradigm'. Network pharmacology has made conventional pharmacology newer while meeting the challenges of this era. Conventional pharmacological methods have not solved the problems of Korean Medicine. For this reason, Network pharmaco- logy needs urgently and desperately for Korean medicine research. However, the information on drug interactions in herbal medicines is complex and less known. There are still some hurdles before network pharmacology emerges, one factor which constitutes Korean medicine research. There is a need to look for solutions other than inheriting the network pharmacology to solve problems that Korean medicine has before. The way of 'in silico' research should be the best to meet this challenge. With the help of 'in silico' research, there might have been emerged new findings of experimental data in Korean Medicine. If 'herbalomics' has been close to foundation through the 'in silico' method, it will contribute to the formation of modern Korean medicine and, simultaneously, come to a foundation for revitalizing exchanges with orthodox Western medicine. Eventually, it ends with a significant profitable and healthy result for the patients.

• Steel and Composite Structures
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• 제45권5호
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• pp.749-766
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• 2022

This paper investigates the seismic performance of exposed RCFST column-base joints, in which the high-strength steel bars (USD 685) are set through the column and reinforced concrete foundation without any base plate and anchor bolts. Three specimens with different axial force ratios (n = 0, 0.25, and 0.5) were tested under cyclic loadings. Finite element analysis (FEA) models were validated in the basic indexes and failure mode. The hysteresis behavior of the exposed RCFST column-base joints was studied by the parametrical analysis including six parameters: width of column (D), width-thickness ratio (D/t), axial force ratio (n), shear-span ratio (L/D), steel tube strength (f_y) and concrete strength (f_c). The bending moment of the exposed RCFST column-base joint increased with D, f_y and f_c. But the D/t and L/D play a little effect on the bending capacity of the new column-base joint. Finally, the calculation formula is proposed to assess the bending moment capacities, and the accuracy and stability of the formula are verified.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.304-309
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• 2023

In the last decade, nuclear medicine appears to be a good choice of medicine. ⁵⁸Co, ⁹⁹Mo, ⁹⁹Tc, ⁹⁹Re, ¹³³Xe and ¹⁸⁶Re are very important radionuclides for nuclear medicine. In this study, the excitation functions of ⁵⁸Ni (n, p) ⁵⁸Co, ⁹⁹Tc (n, p) ⁹⁹Mo, ⁹⁹Ru (n, p) ⁹⁹Tc, ¹³¹Xe (n, p) ¹³¹I, ¹³³Cs (n, p) ¹³³Xe and ¹⁸⁶Os (n, p) ¹⁸⁶Re nuclear reactions were calculated at neutron energies between 1 and 20 MeV using TALYS 1.95 and EMPIRE 3.2 nuclear codes. Furthermore, the cross sections were calculated with the empirical formula derived in our past study at 14-15 MeV. The obtained results were compared with the measured values in EXFOR library, and with the evaluated data of (JENDL-4.0/HE, JEFF-3.3, TENDL-2019, ENDF/B-VIII.0, IRDFF-II, JENDL/ImPACT-18). The results are in good agreement with those of the evaluated data libraries and experimental results and indicates that these radioisotopes can be produced by smaller cyclotrons.

• Advances in Computational Design
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• 제8권2호
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• pp.147-177
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• 2023

Elliptical concrete-filled steel tubular (CFST) column is widely used in modern structures for both aesthetical appeal and structural performance benefits. The ultimate axial load is a critical factor for designing the elliptical CFST short columns. However, there are complications of geometric and material interactions, which make a difficulty in determining a simple model for predicting the ultimate axial load of elliptical CFST short columns. This study aims to propose an efficient adaptive neuro-fuzzy inference system (ANFIS) model for predicting the ultimate axial load of elliptical CFST short columns. In the proposed method, the ANFIS model is used to establish a relationship between the ultimate axial load and geometric and material properties of elliptical CFST short columns. Accordingly, a total of 188 experimental and simulation datasets of elliptical CFST short columns are used to develop the ANFIS models. The performance of the proposed ANFIS model is compared with that of existing design formulas. The results show that the proposed ANFIS model is more accurate than existing empirical and theoretical formulas. Finally, an explicit formula and a Graphical User Interface (GUI) tool are developed to apply the proposed ANFIS model for practical use.

• 대한조선학회지
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• 제27권2호
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• pp.31-39
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• 1990

불규칙 해상을 항해하는 선박이 겪게 되는 갑판침수 현상은 의장품 및 갑판화물의 손상과 승무원의 활동제한 등을 초래하여 선박의 성능을 감소시키는 작용을 하며 거친 해상에서의 잦은 갑판침수는 전복을 야기시킬 수도 있다. 따라서 거친해상에서의 작업이 요구되는 군함이나 갑판에 화물을 적재하게 되는 콘테이너선 등은 설계시 갑판침수 현상을 최소화하기 위한 선수부 현상이 고안되어야 한다, 갑판침수 현상은 현상자체의 비선형성 및 희귀성으로 인해 이론적 추정이 난점이 있으므로 설계목적의 갑판침수 현상해석은 주로 모형시험에 의존하고 있다. 본 논문에서는 용량식 파고계의 원리를 이용한 갑판침수계측 시험방법을 소개하였으며, ITTC 내항성분과 표준모형선인 S-175 고속콘테이너선의 1/43.75 모형으로, 유의파고 7.88m, 평균주기 10.5초의 선수파 해상상태에서 Froude수 0.15와 0.275의 두 조건에 대해 갑판침수계측 시험을 수행하였다. 계측시험 결과를 통계적 관점에서 고찰하였고 Rayleigh 분포의 가정에 따른 Ochi의 갑판침수계산 공식에 의한 계산결과로 비교하였다.

• 물과 미래
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• 제22권2호
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• pp.191-200
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• 1989

소류사의 입자이동속도와 소류사농도의 곱으로 소류사량을 계산할 수 있는 한 방법이 제시되었다. 본 연구에서 사립의 평균이동속도는 하상부근의 유속난류성분의 출현빈도가 정규분포 한다고 가정하고, 입자이동속도를 소류력의 함수와 하상부근의 평균유속의 곱으로 나타내었다. 소류사에 유효하게 작용하는 소류력을 구하기 위해서 Engelund가 제시한 식을 사용하여 유효마찰속도를 구하였으며 Engelund가 제시한 식의 적합성을 간접적으로 검증했다. 소류사농도를 구하기 위해서 호전·도상의 식을 사용하였다. 실험자료는 타 연구자들의 식과 비교되었으며 타 연구자들의 식과 비슷한 경향을 나타내었다. 소류력이 비교적 작은 경우를 제외하고 제시된 식에서 계산된 결과와 타연구자들의 자료는 잘 일치하였다.

• 대한한의학방제학회지
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• 제10권1호
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• pp.169-180
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• 2002

This study was performed to investigate the effects of Radix Puerariae (RP), Flos Puerariae (FP) and Caules in Liquamen Phyllostachyos+Radix Puerariae water extracts on the alcohol dehydrogenase (ADH). transaminase (GOT, GPT) activities, and two hepatic antioxidant enzyme (SOD, catalase) activities in acute ethanol administered mice, and we have investigated the morphological changes that occur in hepatocytes of the experimental mice. The activities of ADH decreased compared with control group in the A1(66%), C1(57%), C2(54%) groups. The transaminase activites increased in the control groups compared with experimental groups. Ethanol treatment group without the RP or FP administration significantly lowered the activities of hepatic SOD and catalase, whereas MnSOD increased in the A1(27%) and B2(43%)groups, CuZnSOD increased in the B2(25%) and C2 groups. The catalase activites were increased in the A1(270%), A2(478%), B2(487%) and B1(770%) compared with control group, A lot of PAS-positive granules were observed in the A1, A2, C1 and C2 groups compared with the other groups. These results suggested that RP, FP and RP+Bamboo extracts administration may be prevent from liver damage in the alcohol treatment mice.

• 대한한의학방제학회지
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• 제25권2호
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• pp.271-302
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• 2017

Objectives : Jakyakgamcho-tang has been used to treat muscular tension, spasm and pain. On this study, new clinical uses of Jakyakgamcho-tang were confirmed and the other pharmacological results were summarized by analysing trends of modern experimental studies and clinical studies. Methods : Papers related to Jakyakgamcho-tang were searched on PUBMED, RISS, and National Assembly Library, and classified by categories and effects of clinical application and a variety of experiment around abstract. Also, figures were used for sketching out a timeline of expressing when these papers were read and core research content was described as a digest for identifying research trends. Results : Until today, there are 104 researches about the antispasmodic, analgesic, anti-inflammatory effects of Jakyakgamcho-tang. In total, 91 papers were analyzed in this study. In matter of subject, researches on the antispasmodic effects were 17 cases, researches on the analgesic effects were 14 cases, researches on gynecological therapeutics were 14 cases, researches on pharmacokinetics were 12 cases, researches on the constituent identification were 7 cases, studies about constituents efficacy were 6 cases, studies about interactions with drugs were 6 cases. Conclusion : The traditional use of Jakyakgamcho-tang on muscle tension, spasm and pain has proven to have effects through the experimental evidences. Other effects of Jakyakgamcho-tang such as gynecological therapeutics, anti-inflammatory effects, are now emerging as a new area in clinical use. Futhermore as an auxiliary treatment, Jakyakgamcho-tang is a good alternative for muscle cramps during maintenance of hemodialysis, myalgia or arthralgia induced by anticancer drugs, amenorrhea induced by neuroleptics.