• Title/Summary/Keyword: Experimental formula

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Transiting test method for galloping of iced conductor using wind generated by a moving vehicle

  • Guo, Pan;Wang, Dongwei;Li, Shengli;Liu, Lulu;Wang, Xidong
    • Wind and Structures
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    • v.28 no.3
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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.

A Comparison Study on Mechanical Properties of XLPE Insulation Thermally Degraded at Equivalent and Variable Temperature Conditions (XLPE 절연체의 등가 및 가변온도 가속열화실험을 통한 기계적 특성 비교 분석)

  • Taejoon, Kim;Jae-Sang, Hwang;Sung Hoon, Jung;Tae Young, Kim
    • KEPCO Journal on Electric Power and Energy
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    • v.8 no.2
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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.

The initial for herbalomics; using "in silico" experiment. (한의학 연구에서 네트워크 약리학의 핵심 연구기법인 "in silico" 연구 방법론의 도입 필요성)

  • Kim, Hong-Man;Ko, Dong-Gun;Park, Sun Dong
    • Herbal Formula Science
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    • v.30 no.3
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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.

Experimental and numerical investigation on exposed RCFST column-base Joint

  • Ben, Mou;Xingchen, Yan;Qiyun, Qiao;Wanqiu, Zhou
    • Steel and Composite Structures
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    • v.45 no.5
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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 (fy) and concrete strength (fc). The bending moment of the exposed RCFST column-base joint increased with D, fy and fc. 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.

Study on (n,p) reactions of 58Ni, 99Tc, 99Ru, 131Xe, 133Cs and 186Os radioisotopes used in medicine

  • Hallo M. Abdullah;Ali H. Ahmed
    • Nuclear Engineering and Technology
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    • v.55 no.1
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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.

Application of ANFIS to the design of elliptical CFST columns

  • Ngoc-Long Tran;Trong-Cuong Vo;Duy-Duan Nguyen;Van-Quang Nguyen;Huy-Khanh Dang;Viet-Linh Tran
    • Advances in Computational Design
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    • v.8 no.2
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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.

Experimental Study on the Deck Wetting of a Container Ship in Irregular Head Waves (콘테이너선의 불규칙파중 갑판침수에 관한 실험적 고찰)

  • Sa-Young,Hong;Pan-Mook,Lee;Do-Sig,Gong
    • Bulletin of the Society of Naval Architects of Korea
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    • v.27 no.2
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    • pp.31-39
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    • 1990
  • Deck wetness phonomena has long been considered as one of the factors that degrade the performance of a ship in waves. In rough weather, the frequent shipping of water may give rise to the capsizing of the ship. Therefore an appropriate above water bow design is an improtant assert to a ship of which successful performance in rough weather is a prerequisite such as a warship. In this paper the experimental technique for estimation of deck wetness frequency is presented. The results of the model tests are compared with those of calculation using Ochi's formula. Finally the applicability of Ochi's formula is discussed.

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A Study on the Bed-Load Transport Rate (소류사량에 관한 연구)

  • Kang, Ju-Bok;Jeong, Yeon-Tae;Kim, Won-Gyu
    • Water for future
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    • v.22 no.2
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    • pp.191-200
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    • 1989
  • A method is presented which enables the computation of the bed-load transport rate as the product of particle velocity and bed-load Concentration. In this study, it is assumed that particle velocity is proportinal to the flow velocity near the particle and the apperance frequency of the component of the fluctuating velocity of turbulent flow close to bed is normally distributed, and the particle velocity is expressed by mean flow velocity near the particle and the function of bed shear stress. Engelund formula, which is checked indirectly to be proper to use in this study, is employed to estimate the effective shear velocity. And the dffective bed shear stress acting on particle is obtained by that shear velocity. Ashida-Michiue's formula is used to get the concentration of bed-load. Experimental data for bed-load is compared with the results of other studies and the transport fornula suggested in this paper gives results which are in good accordance with other's experimental data excepting the results obtained the case of comparatively small bed shear stress.

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Effects of Radix Puerariae, Flos Puerariae and Bamboo+Radix Puerariae Water Extracts on the Ethanol-administered Mice (갈근, 갈화, 갈근과죽력의 추출물이 알코올을 투여한 생쥐에 미치는 영향)

  • Kim Kyung-Soo;Jung Jong-Kil;Na Chang-Su;Kim Jeong-Sang
    • Herbal Formula Science
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    • v.10 no.1
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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.

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A Review Study of Researches on Jakyakgamcho-tang (작약감초탕(芍藥甘草湯)의 연구동향(硏究動向) 분석(分析))

  • Shin, Young Sub;Lee, Soong In
    • Herbal Formula Science
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    • v.25 no.2
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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.