• Smart Structures and Systems
• /
• 제30권6호
• /
• pp.627-637
• /
• 2022

Recent years, direct displacement-based design (DDBD) procedure is proposed for the design of un-bonded posttensioned (UPT) concrete wall systems. In the DDBD procedure, the determination of the equivalent viscous damping (EVD) ratio is critical since it would influence the strength demand of the UPT wall systems. Nevertheless, the influence of EVD ratio determination of the UPT wall systems were not thoroughly evaluated. This study was aimed to investigate the influence of different EVD ratio determinations on the DDBD procedure of UPT wall systems. Case study structures with four, twelve and twenty storeys have been designed with DDBD procedure considering different EVD ratio determinations. Nonlinear time history analysis was performed to validate the design results of those UPT wall systems. And the simulation results showed that the global responses of the case study structures were influenced by the EVD ratio determination.

• 한국수정란이식학회지
• /
• 제28권4호
• /
• pp.343-348
• /
• 2013

Cell-free fetal RNA has been highlighted as useful tools for the fetal sex determination or other genetic inherent disorder. However, there is no knowledge about the sex determination using cell free fetal RNA in bovine field. Thus, the present study aimed to evaluate the presence of transcripts of DDX3Y, USP9Y and ZRSR2Y genes in maternal plasma of pregnant cows to determine the sex of the fetus using real-time quantitative polymerase chain reaction assay, and verify its accuracy, sensitivity and specificity compared with the molecular testing and the calf sex at birth. Transcripts of USP9Y and DDX3Y genes were expressed in the all plasma of males and females both the control group and the experimental group. However, ZRSR2Y gene was matched up with the molecular testing and the true sex in control group and has an overall accuracy of 82.6%, a sensitivity of 75%, and a specificity of 100% in experimental group. Therefore, these results indicated that real time PCR technique, as a noninvasive and cost-efficient method, is possible to determination fetal sex in the bovine species using circulating cell free RNA in maternal plasma and especially ZRSR2Y gene could be a good candidate for the RNA based sex determination work.

• 약학회지
• /
• 제21권1호
• /
• pp.27-29
• /
• 1977

Amoxicillin formed blue color when heated with phophomolybdic acid in adequate condition, and the color showed maximal absorbance at 760nm. Effect of pH, concentration of phosphomolybdic acid and reating time were studied. And a new colorimetric method of determination of amoxicillin was developed.

• Journal of Astronomy and Space Sciences
• /
• 제29권4호
• /
• pp.351-362
• /
• 2012

We made a study on real-time determination method for relative position using the laser-measured distance data between satellites. We numerically performed the determination of relative position in accordance with extended Kalman filter algorithm using the vectors obtained through nonlinear equation of relative motion, laser simulator for distance measurement, and attitude determination of chief satellite. Because the spherical parameters of relative distance and direction are used, there occur some changes in precision depending on changes in relative distance when determining the relative position. As a result of simulation, it was possible to determine the relative position with several millimeter-level errors at a distance of 10 km, and sub-millimeter level errors at a distance of 1 km. In addition, we performed the determination of relative position assuming the case that global positioning system data was not received for long hours to see the impact of determination of chief satellite orbit on the determination of relative position. The determination of precise relative position at a long distance carried out in this study can be used for scientific mission using the satellite formation flying.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.92.4-92
• /
• 2001

Estimation of the general along-track acceleration was performed in the KOMPSAT-1 orbit determination process. Several sets of the atmospheric drag and solar radiation pressure coefficients were also derived with the different spacecraft area. State vectors in the orbit determination with the different spacecraft area were compared in the time frame. The orbit prediction using the estimated coefficients was performed and compared with the orbit determination results. The orbit prediction with the different general acceleration values was also carried out for the comparison.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1992년도 춘계학술대회 논문집
• /
• pp.200-205
• /
• 1992

This study concerns about the orbit prediction and orbit determination of Korean future connumication satellite, called "Moogunghwa" , which will be motioned in the geo-stationary orbit. Perturbation effect on the satellite orbit due to nonspherical term, lunar and solar gravity, drag force of the atmospher, and solar radiation pressure was investigated. Cowell's method is used for orbit prediction. Orbit determination was performed by using Extended Kalman Filter which is suitable for real-time orbit determination. The result shows that the chacteristics of the satellite orbit has east-west and south-north drift. So the periodic control time and control value in the view of the periodic of error can be provided. The orbit determination demonstrated the effectiveness since the convergence performance on the positon and velocity error, and state error standard deviation is reasonable.

• Bulletin of the Korean Chemical Society
• /
• 제24권9호
• /
• pp.1261-1264
• /
• 2003

A method for the determination of trace amount of sulfide based on the addition reaction of sulfide with methyl green at pH 7.5 and $25{\circ}C$ is described. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of the dyestuff at 637 nm by the initial rate and fixed time method. The calibration graph is linear in the range 30-1200 ppb. The theoretical limit of detection was 0.014 ppm. Seven replicate analysis of a sample solution containing 0.70 ppm sulfide gave a relative standard deviation of 1.5%. The interfering effects of various ions on sulfide determination have been reported and procedures for removal of interference have been described. The proposed method was applied successfully to the determination of sulfide in tap and wastewater samples.

• Nuclear Engineering and Technology
• /
• 제53권12호
• /
• pp.4093-4097
• /
• 2021

This study presents a new dead-time measurement method using the gamma attenuation law and generalized dead-time models for nuclear gamma-ray detectors. The dead-time of the NaI(Tl) detection system was obtained to validate the new dead-time determination method using very thin lead and polyethylene absorbers. Non-paralyzing dead-time was found to be 8.39 ㎲, and paralyzing dead-time was found to be 8.35 ㎲ using lead absorber for NaI(Tl) scintillator detection system. These dead-time values are consistent with the previously reported dead-time values for scintillator detection systems. The gamma build-up factor's contribution to the dead-time was neglected because a very thin material was used.

• Journal of Astronomy and Space Sciences
• /
• 제21권3호
• /
• pp.221-232
• /
• 2004

TLE로부터 SGP4/SDP4 모델을 이용하여 인공위성의 가상의 위치 정보를 얻은 후 Gauss 방법을 사용하여 인공위성의 예비궤도를 결정해보았다. 예비궤도 결정에 필요한 임의의 세 점 사이의 시간간격을 변화시켜 얻은 결과를 위성의 위치 참값과 비교하여 최소의 차이를 가지는 관측 시간 간격을 찾아보았으며, Gauss 예비궤도 결정법의 성능을 비교, 분석하였다. 실제 인공위성 관측 결과와의 비교를 위해서 한국천문연구원의 광시야 망원경을 사용하여 GPS위성(PRN 26)과 무궁화 2호의 광학관측 데이터를 얻은 후 같은 방법으로 예비궤도를 결정해 보았다. 인공위성의 정밀궤도결정을 위하여 시뮬레이션에서 얻어진 가상의 광학관측 데이터를 가지고 정밀케도결정을 수행하였으며, 관측 데이터의 오차와 관측 시간 간격에 따라 정밀궤도결정을 수행하여 원하는 정밀도를 얻기 위한 관측 시스템의 조건에 대해서 알아보았다.

• Bulletin of the Korean Chemical Society
• /
• 제21권4호
• /
• pp.419-424
• /
• 2000

In this study we have investigated the determination of proper time step in molecular dynamics simulation.Since the molecular dynamics is mathematically related to nonlinear dynamics, the analysis of eigenvalues isused to explain the relationship between the time step and dynamics. The tracings of H2 and CO2 molecular dynamics simulation agrees very well with the analytical solutions. For H2, the time step less than 1.823 fs pro-vides stable dynamics. ForCO2, 3.808 fs might be the maximum time step for proper molecular dynamics. Al-though this results were derived for most simple cases of hydrogen and carbon dioxide, we could quantitatively explain why improperly large time step destroyed the molecular dynamics. From this study we could set the guide line of the proper time step for stable dynamics simulation in molecular modeling software.