• Journal of Astronomy and Space Sciences
• /
• v.33 no.4
• /
• pp.247-256
• /
• 2016

An analysis of light curves and spectra of observed gamma-ray bursts in gamma-ray ranges is frequently demanded because the prompt emission contains immediate details regarding the central engine of gamma-ray bursts (GRBs). We have revisited the relationship between the collimation-corrected peak luminosity and the spectral lag, investigating the lag-luminosity relationships in great detail by focusing on spectral lags resulting from all possible combinations of channels. Firstly, we compiled the opening angle data and demonstrated that the distribution of opening angles of 205 long GRBs is represented by a double Gaussian function having maxima at ~ 0.1 and ~ 0.3 radians. We confirmed that the peak luminosity and the spectral lag are anti-correlated, both in the observer frame and in the source frame. We found that, in agreement with our previous conclusion, the correlation coefficient improves significantly in the source frame. It should be noted that spectral lags involving channel 2 (25-50 keV) yield high correlation coefficients, where Swift/Burst Alert Telescope (BAT) has four energy channels (channel 1: 15-25 keV, channel 2: 25-50 keV, channel 3: 50-100 keV, channel 4: 100-200 keV). We also found that peak luminosity is positively correlated with peak energy.

• The Journal of Korean Medical History
• /
• v.23 no.1
• /
• pp.67-75
• /
• 2010

This study was done to research "Ke Sou Lun" of ${\ll}$Yi Guan${\gg}$ of Zhao Xian Ke. The results obtained as follows. 1) He suggested the treatment of chronic cough to strengthen 'Pitu' and 'Shenshui'. 2) He treated chronic cough patient without 'Qingjin' and 'Qinghuo' therapy that use cold herb. 3) We can strengthen 'Yang', after strengthen 'Zhenyin' in case of the chronic cough that contained 'Huo'.

• Composites Research
• /
• v.18 no.6
• /
• pp.48-53
• /
• 2005

In this study, to improve the ballistic efficiency of very brilliant alumina-silica armor material, forming press and sintering temperature were changed. After physical/mechanical measurement, we measured ballistic properties about KE(Kinetic Energy, L/D=10.7, tungsten heavy alloy) and HEAT(High Explosive Anti-Tank, K215) projectiles and analyzed them. As a result, in $1235^{\circ}C$, it appeared the highest ballistic efficiency about HEAT and it improved $22\%$ ballistic efficiency, better than invented alumina-silica armor material before.

• Progress in Medical Physics
• /
• v.4 no.2
• /
• pp.27-36
• /
• 1993

A relative efficiency of a HPGe detector as a function of the incident gamma ray energy in the range 120 keV to 1500 keV was measured using 21 gamma rays emitted by a $\^$152/Eu source. A semiempirical expression was then determined which can reproduce the measured values reasonably well. The two results are compared to a Monte Carlo simulation calculation.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.24 no.6
• /
• pp.907-910
• /
• 2010

In Traditional Oriental Medicine, the drug treatment has been explained by the thoery of "Si Qi Wu Wei(四氣五味)". Among them, Xin(辛) has effect of Sheng(升), San(散), Xing(行), and Ku(苦) has effect of Jiang xia(降下), Zao shi(燥濕), Jian yin(堅陰). The study on the medical action of Asari Radix shows that "Xin ke run zao(辛可潤燥)" was derived from Sheng(升), San(散), Xing(行) efficacy of sour. And the study on the medical action of Phellodendron Bark, Anemarrhenae Rhizoma shows that "Ku ke run zao(苦可潤燥)" was derived from Xie(泄) efficacy of bitter.

• Annual Conference on Human and Language Technology
• /
• 2021.10a
• /
• pp.505-506
• /
• 2021

최근 인터넷에서 기하급수적으로 증가하는 방대한 양의 텍스트를 자동으로 요약하려는 연구가 활발하게 이루어지고 있다. 자동 텍스트 요약 작업은 다양한 사전학습 모델의 등장으로 인해 많은 발전을 이루었다. 특히 T5(Text-to-Text Transfer Transformer) 기반의 모델은 자동 텍스트 요약 작업에서 매우 우수한 성능을 보이며, 해당 분야의 SOTA(State of the Art)를 달성하고 있다. 본 논문에서는 방대한 양의 한국어를 학습시킨 사전학습 모델 KE-T5를 활용하여 자동 논문 요약을 수행하고 평가한다.

• Journal of the Korea Convergence Society
• /
• v.8 no.1
• /
• pp.43-49
• /
• 2017

In the analyzed cardiac CT algorithm applied when comparing the MAR self-made metal artifact reduction in pacemaker inserted phantom degree. Result of comparing the energy value by CT showed a decrease in the CT value in the case of BKG 40 KeV in WSA maximum decreased to 663.2% in the case of 140 KeV BHA were increased a maximum of 56.2%. In addition, the maximum was decreased by approximately 145% based on a 70 KeV artifacts in CT value comparison by type WSA, BHA was to increase up to approximately 46.38%. MAR Algorithm is believed to provide a more quality cardiac CT image if the energy changes, or have the effect that by type and irrespective of reduced metal artifacts occurrence of artifacts applied to the pacemaker when tracking a heart CT scan after inserting MAR algorithm.

• Journal of the Korean Society of Safety
• /
• v.32 no.6
• /
• pp.29-33
• /
• 2017

In order to solve this sort of electrostatic failure in Display and Semiconductor process, Soft X-ray ionizer is mainly used. Soft X-ray Ionizer does not only generate electrical noise and minute particle but also is efficient to remove electrostatic as it has a wide range of ionization. There exist variable factors such as type of tungsten thickness deposited on target, Anode voltage etc., and it takes a lot of time and financial resource to find optimal performance by manufacturing with actual X-ray tube source. Here, MCNPX (Monte Carlo N-Particle Extended) is used for simulation to solve this kind of problem, and optimum efficiency of X-ray generation is anticipated. In this study, X-ray generation efficiency was compared according to target material thickness using MCNPX and actual X-ray tube source under the conditions that tube voltage is 5 keV, 10 keV, 15 keV and the target Material is Tungsten(W). At the result, In Tube voltage 5 keV and distance 100 mm, optimal target thickness is $0.05{\mu}m$ and fastest decay time appears + decay time 0.28 sec. - deacy time 0.30 sec. In Tube voltage 10keV and distance 100 mm, optimal target Thickness is $0.16{\mu}m$ and fastest decay time appears + decay time 0.13 sec. - deacy time 0.12 sec. In the tube voltage 15 keV and distance 100 mm, optimal target Thickness is $0.28{\mu}m$ and fastest decay time appears + decay time 0.04 sec. - deacy time 0.05 sec.

• Journal of radiological science and technology
• /
• v.41 no.2
• /
• pp.129-134
• /
• 2018

The present study made a phantom for gamma ray of 140 keV radiated from $^{99m}Tc$, examined shielding effect of lead by thickness of the shielding material, and measured surface dose and depth dose by body depth. The OSL Nano Dot dosimeter was inserted at 0, 3, 15, 40, 90, and 180 mm depths of the phantom, and when there was no shield, 0.2 mm lead shield, 0.5 mm lead shield, The depth dose was measured. Experimental results show that the total cumulative dose of dosimeters with depth is highest at 366.24 uSv without shield and lowest at 94.12 uSv with 0.5 mm lead shield. The shielding effect of 0.2 mm lead shielding was about 30.18% and the shielding effect of 0.5 mm lead shielding was 74.30%, when the total sum of the accumulated doses of radiation dosimeter was 100%. The phantom depth and depth dose measurements showed the highest values at 0 mm depth for all three experiments and the dose decreases as the depth increases. This study proved that the thicker a shielding material, the highest its shielding effect is against gamma ray of 140 keV. However, it was known that shielding material can't completely shield a body from gamma ray; it reached deep part of a human body. Aside from the International Commission on Radiation Units and Measurements (ICRU) recommending depth dose by 10 mm in thickness, a plan is necessary for employees working in department of nuclear medicine where they deal with gamma ray, which is highly penetrable, to measure depth dose by body depth, which can help them manage exposed dose properly.

• Nuclear Engineering and Technology
• /
• v.52 no.7
• /
• pp.1565-1570
• /
• 2020

Photons with the energy of 60 keV are regularly used for some kinds of bone density examination devices, like the single photon absorptiometry (SPA). This article reports a flexible and lightweight rare earth/polymer composite for enhancing shielding efficiency against photon radiation with the energy of 60 keV. Lead oxide (PbO) and several rare earth element oxides (La₂O₃, Ce₂O₃, Nd₂O₃) were dispersed into natural rubber (NR) and the photon radiation shielding performance of the composites were assessed using monte carlo simulation method. For 60 keV photons, the shielding efficiency of rare earthbased composites were found to be much higher than that of the traditional lead-based composite, which has bad absorbing ability for photons with energies between 40 keV and 88 keV. In comparison with the lead oxide based composite, Nd₂O₃-NR composite with the same protection standard (the lead equivalent is 0.25 mmPb, 0.35 mmPb and 0.5 mmPb, respectively), can reduce the thickness by 35.29%, 37.5% and 38.24%, and reduce the weight by 38.91%, 40.99% and 41.69%, respectively. Thus, a flexible, lightweight and lead-free rare earth/NR composite could be designed, offering efficient photon radiation protection for the users of the single photon absorptiometry (SPA) with certain energy of 60 keV.