http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kinetics calculation of fast periodic pulsed reactors using MCNP6
Z. Zhong,Y. Gohar,A. Talamo,Y. Cao,I. Bolshinsky,Yu N. Pepelyshev,Alexander Vinogradov 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.7
Fast periodic pulsed reactor is a type of reactor in which the fission bursts are formed entirely withexternal reactivity modulation with a specified time periodicity. This type of reactors could generatemuch larger intensity of neutron beams for experimental use, compared with the steady state reactors. Inthe design of fast periodic pulsed reactors, the time dependent simulation of the power pulse is majorlybased on a point kinetic model, which is known to have limitations. A more accurate calculation methodis desired for the design analyses of fast periodic pulsed reactors. Monte Carlo computer code MCNP6 isused for this task due to its three dimensional transport capability with a continuous energy library. Some new routines were added to simulate the rotation of the movable reflector parts in the timedependent calculation. Fast periodic pulsed reactor IBR-2M was utilized to validate the new routines. This reactor is periodically in prompt supercritical state, which lasts for ~400 ms, during the equilibriumstate. This generates long neutron fission chains, which requires tremendously large amount ofcomputation time during Monte Carlo simulations. Russian Roulette was applied for these very longneutron chains in MCNP6 calculation, combined with other approaches to improve the efficiency of thesimulations. In the power pulse of the IBR-2M at equilibrium state, there is some discrepancy betweenthe experimental measurements and the calculated results using the point kinetics model. MCNP6 resultsmatches better the experimental measurements, which shows the merit of using MCNP6 calculationrelative to the point kinetics model.
CHOI, Byung-Tae,PARK, Hyung Dal,TAE, Heung-Sik The Institute of Electronics, Information and Comm 2009 IEICE transactions on electronics Vol.92 No.11
<P>To explain the variation of the address discharge during an address period, the wall voltage variation during an address period was investigated as a function of the address-on-time by using the <I>V<SUB>t</SUB></I> closed curves. It was observed that the wall voltage between the scan and address electrodes was decreased with an increase in the address-on-time. It was also observed that the wall voltage variation during an address period strongly depended on the voltage difference between the scan and address electrodes. Based on this result, the modified driving waveform to raise the level of <I>V<SUB>scanw</SUB></I>, was proposed to minimize the voltage difference between the scan and address electrodes. However, the modified driving waveform resulted in the increase in the falling time of scan pulse. Finally, the overlapped double scan waveform was proposed to reduce a falling time of scan pulse under the raised voltage level of V<SUB>scanw</SUB>, also.</P>
WMTS 무선통신 모듈을 이용한 맥파의 주기검출 및 감성평가 시스템 개발
이현민(Hyun-Min Lee),김동준(Dong-Jun Kim),전기만(Ki-Man Jeon),손재기(Jae-Gi Son) 대한전기학회 2013 전기학회논문지 Vol.62 No.6
In this study we present a system for pulse-rate period detection and human sensibility evaluation based on the wireless medical telemetry service (WMTS) used for transmission of data from medical telemetry devices to various medical facilities and services. We develop a medical-purpose specific WMTS communication module to transmit biometric signals. From the pulse rate variability(PRV) signal, we attempt to classify positive and negative emotional states based on analysis of the ratio of LF/HF in the frequency domain. We measure the data reception rate according to distance in order to test the performance of the WMTS module and analyze the effects on human sensibility evaluation.
이현민(Hyun-Min Lee),김동준(Dong-Jun Kim) 대한전기학회 2009 전기학회논문지 Vol.58 No.6
Heart rate may be a very important parameter in human health. To extract heart rate, the electrocardiogram(ECG) is commonly used. But the ECG acquisition procedure is very complex. On the other hand, the acquisition of pulse wave or photoplethysmogram(PPG) is very easy. However, the peak of PPG is not so sharp as ECG. This study tries to enhance the performance of peak detection in PPG signal. The method uses the average slopes around the main peak. The crossing point of the increasing and the decreasing slopes is selected as the peak point of heart rate period. The proposed method showed smoothed heart rate graph and reduced irregularity in heart rate values.
Behnoud Ganjavi,Amirali Hadinejad,Amir Hossein Jafarieh 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.32 No.1
In the present study, the effects of six different ground motion scaling methods on inelastic response of nonlinear steel moment frames (SMFs) are studied. The frames were designed using energy-based PBPD approach with the design concept using pre-selected target drift and yield mechanism as performance limit state. Two target spectrums are considered: maximum credible earthquake spectrum (MCE) and design response spectrum (DRS). In order to investigate the effects of ground motion scaling methods on the response of the structures, totally 3216 nonlinear models including three frames with 4, 8 and 16 stories are designed using PBPD approach and then they are subjected to ensembles of ground motions including 42 far-fault and 90 near-fault pulse-type records which were scaled using the six different scaling methods in accordance to the two aforementioned target spectrums. The distributions of maximum inter-story drift over the height of the structures are computed and compared. Finally, the efficiency and reliability of each ground motion scaling method to estimate the maximum nonlinear inter-story drift of special steel moment frames designed by energy-based PBPD approach are statistically investigated, and the most suitable scaling methods with the lowest dispersion for two groups of earthquake ground motions are introduced.
Bedenko, Sergey V.,Arzhannikov, Andrey V.,Lutsik, Igor O.,Prikhodko, Vadim V.,Shmakov, Vladimir M.,Modestov, Dmitry G.,Karengin, Alexander G.,Shamanin, Igor V. Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.6
The results of full-scale numerical experiments of a hybrid thorium-containing fuel cell facility operating in a close-to-critical state due to a controlled source of fusion neutrons are discussed in this work. The facility under study was a complex consisting of two blocks. The first block was based on the concept of a high-temperature gas-cooled thorium reactor core. The second block was an axially symmetrical extended plasma generator of additional neutrons that was placed in the near-axial zone of the facility blanket. The calculated models of the blanket and the plasma generator of D-T neutrons created within the work allowed for research of the neutronic parameters of the facility in stationary and pulse-periodic operation modes. This research will make it possible to construct a safe facility and investigate the properties of thorium fuel, which can be continuously used in the epithermal spectrum of the considered hybrid fusion-fission reactor.
주기 발열 파형을 이용한 열식 질량 유량계의 특성에 관한 수치적 연구
전홍규(Hong Kyu Jeon),오동욱(Dong Wook Oh),박병규(Byung Kyu Park),이준식(Joon Sik Lee) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5
Numerical simulations are conducted for the analysis of a thermal mass air flow sensor with periodic heating pulses on silicon-nitride (Si₃N₄) thin membrane structure. This study ai㎳ to find the locations of temperature sensors on the thin membrane and the heating pulse conditions, that the higher sensitivity can be achieved, for the development of a MEMS fabricated mass air flow sensor which is driven in periodic heating pulse. The simulations, thus, focus on the membrane temperature profile according to variation of the flow velocity, heating duration time and imposed power. The flow velocity of the simulations is ranging from 3 ㎧ to 35 ㎧, heating duration time from 1 ㎳ to 3 ㎳ and imposed power from 50 ㎽ to 90 ㎽. The corresponding Reynolds numbers vary from 1000 to 10000.
낙엽송 간벌 작업에서 순수작업시간과 심박수에 따른 휴식시간과의 관계 연구
강건우 영남대학교 자원문제연구소 2000 資源問題硏究 Vol.19 No.-
The pupose of this study was to standardise the forest working system to design the intensity of working system in felling operation of the thinning forest in Korea as well as to contrive the improvement of working method and the increase of productivity. For the purpose of investigating these, element working was classified by felling operation in Japanese larch thinning forest, and recess periods and pulse rates were measured and analyzed. The results were as follows : 1. An estimated Net working time is resulted in 237sec./tree for at average DBH 14.5cm. 2. The pulse frequence per minute were 120 pulses in average in the choice of fellingdirectory, 123 pulses in the circumference, 129 pulses in the felling operation, 132 pulses in hang-up and 139 pulses in the novement. 3. From the results of the Hulse frequence analysis, average putse frequence in net working time showed 131 pulses pef minute. 4. Excess DLG(DauerleishHgsgrenze) which indicates the working intensity Thor'ed 21 pulses per minute. 5. An estimated recess period is resulted in 140sec. over net working time(180sec.). 6. The ratio of recess period(140sec.) over net working time(180sec.) showed 77%.
이지연 ( Ji Yeon Lee ),유정은 ( Jeong Eun Yoo ),윤영진 ( Young Jin Yun ) 대한한방부인과학회 2013 大韓韓方婦人科學會誌 Vol.26 No.4
The purpose of this study is to investigate the change and correlation of pulse energy in Left and Right Chon, Kwan, Cheok during menstruation,especially around menstruation start date. Methods: The subjects of this experiment were 8 healthy women whose menstruation periods are regular. We measured 3D Blood Pressure Pulse Analyzer (3D-MAC)tests before and after menstruation start date. Results: The results were as follows 1. The pulse energy of the Right Chon was significantly decreased and Left Kwan was comparatively increased during the next day of menstruation start date than previous day. 2. There was a negative correlation between Left Kwan and Left Cheok, Right Chon and Right Kwan pulse energy during the previous and menstruation start date. The negative correlation disappeared between Right Chon and Right Kwan at the next day of menstruation start date. Conclusions: The results suggest that Chon, Kwan, Cheok pulse energy changes are related to menstruation and reflect physiological mechanism of menstruating women. Further study will be needed.