• 제목/요약/키워드: Reversal Effect

검색결과 239건 처리시간 0.045초

무전극 황방전등에서 고압 이원자 황($S_2$)의 자체 역전 효과 (Self Reversal Effect of the High-pressured Diatomic Sulfur in the Electrodeless Sulfur Discharge Lamp)

  • 추장희;구선근;박기준;이영우
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권11호
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    • pp.609-615
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    • 2000
  • A prototype electrodeless sulfur lamp was developed and investigated the spectroscopic characteristics. The emission spectra of $S_2$ in the microwave-discharged eletrodeless sulfur lamp (ESL) were studied at various input power. The emission spectra of the ESL shift to longer wavelength with increasing of the input power. We have shown that this is due to the self reversal effect in the high pressure gas discharge. We also show that the self reversal effect increases as the rotation of the discharged bulb. The spectral distribution of the ESL shifts about 45 nm toward visible region from UV region due to the rotation of the lamp bulb.

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펌프장 정전시 역류발생시간에 관한 연구 (A Study on the Reversal Flow Time due to Blackout)

  • 박종호;박한영
    • 한국유체기계학회 논문집
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    • 제14권6호
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    • pp.26-34
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    • 2011
  • Waterhammer and slamming phenomena can occur when power is cut off due to reversal flow in pipeline and sudden close of check valve. Therefore analysis of reversal flow time, which means the time of reversal flow in pipeline due to pumping station blackout, is needed to protect facilities from waterhammer economically and efficiently. However systematic study on reversal flow time has not been done yet. So theory of reversal flow time analysis is proposed and verified with experiment using several parameters like pump specific speed, motor pole number, and characteristic curve of pipeline in this study.

Comparative evaluation of photobiomodulation therapy at 660 and 810 nm wavelengths on the soft tissue local anesthesia reversal in pediatric dentistry: an in-vivo study

  • Ankita Annu;Sujatha Paranna;Anil T. Patil;Sandhyarani B.;Adhithi Prakash;Renuka Rajesh Bhurke
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제23권4호
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    • pp.229-236
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    • 2023
  • Background: Local anesthesia has been reliably used to control pain during dental procedures and is important in pediatric dentistry. However, children occasionally complain of prolonged numbness after dental treatment, leading to several problems. Studies conducted to reverse the effect of local anesthesia using phentolamine mesylate and photobiomodulation therapy (PBM) are encouraging but limited. PBM is a type of light therapy that utilizes visible and near-infrared non-ionizing electromagnetic spectral light sources. Hence, this study used this modality to compare the reversal of local anesthesia at two different wavelengths. This study compared the effect of PBM at 660 and 810 nm wavelengths on the reversal of soft tissue local anesthesia using a diode LASER in pediatric dentistry. Method: Informed consent and assent were obtained, and the participants were then divided randomly into three groups of 20 children each: control group-without LASER irradiation, LASER irradiation at 660 nm, and LASER irradiation at 810 nm. Sixty children aged 4-8 years with deciduous mandibular molars indicated for pulp therapy were administered an inferior alveolar nerve block. After 45 min of injection, a duration that was similar to the approximate duration of treatment, they were exposed to 660- and 810-nm LASER irradiation according to their groups until reversal of local anesthesia was achieved. The control group did not undergo LASER irradiation. The reversal of the soft tissue local anesthetic effect was evaluated using palpation and pin prick tests every 15 min, and the LASER irradiation cycle continued until reversal of the soft tissue local anesthesia was achieved. Results: A significant reduction of 55.5 min (27.6%) in the mean soft tissue local anesthesia reversal time was observed after the application of 810 nm wavelength PBM and 69 min (34.7%) after 660 nm wavelength LASER irradiation. Conclusion: PBM with a 660 nm wavelength was more effective in reducing the mean soft tissue local anesthesia reversal duration, and thus can be used as a reversal agent for soft tissue local anesthesia in pediatric dentistry.

Magnetisation reversal dynamics in epitaxial Fe/GaAs(001) and Fe/InAs(001) thin films

  • Lee, W. Y.;K. H. Shin;Kim, H. J.
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
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    • pp.230-238
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    • 2000
  • We present the magnetisation reversal dynamics of epitaxial Fe thin films grown on GaAs(001) and InAs(001) studied as a function of field sweep rate in the range 0.01-160 kOe/s using magneto-optic Kerr effect (MOKE). For 55 and 250 ${\AA}$ Fe/GaAs(001), we find that the hysteresis loop area A follows the scaling relation A ∝ H$\^$${\alpha}$/ with ${\alpha}$=0.03∼0.05 at low sweep rates and 0.33-0.40 at high sweep rates. For the 150 ${\AA}$ Fe/InAs(001) film, ${\alpha}$ is found to be ∼0.02 at low sweep rates and ∼0.17 at high sweep rates. The differing values of ${\alpha}$ are attributed to a change of the magnetisation reversal process with increasing sweep rate. Domain wall motion dominates the magnetisation reversal at low sweep rates, but becomes less significant with increasing sweep rate. At high sweep rates, the variation of the dynamic coercivity H$\sub$c/ is attributed to domain nucleation dominating the reversal process. The results of magnetic relaxation studies for easy-axis reversal are consistent with the sweeping of one or more walls through the entire probed region (∼100 $\mu\textrm{m}$). Domain images obtained by scanning Kerr microscopy during the easy cubic axis reversal process reveal large area domains separated by zigzag walls.

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Effect of cross-sectional vortex formation on magnetization reversal in rectangular shaped Permalloy nanowires

  • Khan, Imran;Hong, Jisang;Hwang, Chanyong
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2013년도 자성 및 자성재료 국제학술대회
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    • pp.115-115
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    • 2013
  • In order to pinpoint the different factors responsible for magnetization reversal, we performed simulation using OOMMF micromagnetic package for rectangular shaped permalloy element having length of $1{\mu}m$, width 50-100 nm and thickness 15-80 nm with length to width ratio L/W>4. Interestingly an increase in coercivity with thickness is found for every width below a critical thickness. With increasing width and thickness, the distinct behavior of coercivity, hysteresis loops and reversal mechanism are presented. Vortex end domains are observed during the magnetization reversal beyond particular thickness, where the three dimension reversal mechanism is expected to begin, causing a sudden increase in coercivity.

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비비례하중을 고려하는 개선소성힌지 해석을 이용한 3차원 강뼈대 구조물의 해석 (3-D Frame Analysis Using Refined Plastic Hinge Analysis Accounting for Non-Proportional Loading)

  • 김창성;김승억;주환중
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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    • pp.77-84
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    • 2003
  • In this paper, the refined plastic-hinge analysis accounting for the effect of strain reversal caused by non-proportional loading is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem, conventional refined plastic-hinge analyses have underestimated the strength of structures subjected to non-proportional loading, is overcome. The modified stiffness degradation model approximating the effect of strain reversal is discussed in detail. The proposed analysis is verified by the comparison of the finite element analysis. A case study shows that the effect of strain reversal is a very crucial element to be considered in second-order plastic-hinge analysis. The proposed analysis is shown to be an efficient, reliable tool ready to be implemented into design practice.

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Inter-Factor Determinants of Return Reversal Effect with Dynamic Bayesian Network Analysis: Empirical Evidence from Pakistan

  • HAQUE, Abdul;RAO, Marriam;QAMAR, Muhammad Ali Jibran
    • The Journal of Asian Finance, Economics and Business
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    • 제9권3호
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    • pp.203-215
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    • 2022
  • Bayesian Networks are multivariate probabilistic factor graphs that are used to assess underlying factor relationships. From January 2005 to December 2018, the study examines how Dynamic Bayesian Networks can be utilized to estimate portfolio risk and return as well as determine inter-factor relationships among reversal profit-generating components in Pakistan's emerging market (PSX). The goal of this article is to uncover the factors that cause reversal profits in the Pakistani stock market. In visual form, Bayesian networks can generate causal and inferential probabilistic relationships. Investors might update their stock return values in the network simultaneously with fresh market information, resulting in a dynamic shift in portfolio risk distribution across the networks. The findings show that investments in low net profit margin, low investment, and high volatility-based designed portfolios yield the biggest dynamical reversal profits. The main triggering aspects related to generation reversal profits in the Pakistan market, in the long run, are net profit margin, market risk premium, investment, size, and volatility factor. Investors should invest in and build portfolios with small companies that have a low price-to-earnings ratio, small earnings per share, and minimal volatility, according to the most likely explanation.

Permalloy/Cu 다층막 자화반전의 미세 구조 (Fine Structure in Magnetization Reversal of Permalloy/Cu Multilayer)

  • 이긍원;염민수;장인우;변상진;이제형;박병기
    • 한국자기학회지
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    • 제11권5호
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    • pp.179-183
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    • 2001
  • Glass/Ni$_{83}$Fe$_{17}$(2 nm)/[Cu(2 nm)Ni$_{83}$Fe$_{17}$(20 nm)]$_{50}$ 다층박막의 평면 홀 효과를 측정하였다. 평면 홀 효과에서 반복된 톱니모양의 홀 효과 신호가 관측되었다. 그 원인으로 갑작스러운 자벽의 이동이 홀 효과로 관측된 것이라는 가설을 세울 수 있다. 이러한 톱니모양의 평면 홀 효과는 모든 측정방향에서 관측되었다. 각 자성층의 전체 자화만이 자기저항을 결정하므로 자기저항의 특성곡선에서는 이러한 톱니모양에 해당하는 신호가 관측되지 않았다. 톱니모양의 근본 원인에 대한 연구는 더욱 수행되어야할 것이다.것이다.

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PNF의 안정적 반전과 율동적 안정화 기법을 이용한 체간 안정화 훈련이 뇌졸중 환자의 체간 근력과 균형 능력에 미치는 영향 (Effect of Trunk Stability Exercises with Stabilizing Reversal and Rhythmic Stabilization of PNF for Muscle Strength and Balance Ability in Stroke Patients)

  • 강태우;함규하
    • PNF and Movement
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    • 제12권2호
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    • pp.63-69
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    • 2014
  • Purpose: The purpose of this study was to investigate the effect that trunk stability exercises with stabilizing reversal and rhythmic stabilization of PNF have on trunk strength and balance ability in stroke patients. Methods: This study included 20 stroke patients who performed trunk stability exercises combined with stabilizing reversal and rhythmic stabilization of PNF. The exercise program consisted of 30-minute sessions per week for six weeks. Trunk strength (BTE, Primus RS) and balance ability (Berg Balance Scale) were evaluated before and after training. All data were analyzed using SPSS 18.0 software. Results: Significant differences were observed the both groups for truck strength and balance ability. The results of the study were as follows: trunk strength was significantly increased in both groups (p<.05) and it was also found to be significant between groups after the intervention (p<.05). Balance ability was significantly increased in both groups (p<.05) and it was also found to be significant between the groups after intervention (p<.05). Conclusion: Trunk stability exercises with stabilizing reversal and rhythmic stabilization of PNF are effective for improving trunk strength and balance ability in stroke patients. For stroke patients, trunk stability exercises with PNF are very useful and effective and they areeffectiveinclinicalpractice.

Expiration-Day Effects on Index Futures: Evidence from Indian Market

  • SAMINENI, Ravi Kumar;PUPPALA, Raja Babu;MUTHANGI, Ramesh;KULAPATHI, Syamsundar
    • The Journal of Asian Finance, Economics and Business
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    • 제7권11호
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    • pp.95-100
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    • 2020
  • Nifty Bank Index has started trading in futures and options (F&O) segment from 13th June 2005 in National Stock Exchange. The purpose of the study is to enhance the literature by examining expiration effect on the price volatility and price reversal of Underlying Index in India. Historical data used for the current study primarily comprise of daily close prices of Nifty Bank which is the only equity sectoral index in India which is traded in derivatives market and its Future contract value is derived from the underlying CNX Bank Index during the period 1st January 2010 till 31st March 2020. To check stationarity of the data, Augmented Dicky Fuller test was used. The study employed ARMA- EGARCH model for analysing the data. The empirical results revealed that there is no effect on the mean returns of underlying Index and EGARCH (1,1) model furthermore shows there is existence of leverage effect in the Bank Index i.e., negative shocks causes more fluctuations in the Index than positive news of similar magnitude. The outcome of the study specifies that there is no effect on volatility on the underlying sectoral index due to expiration days and also observed no price reversal effect once the expiration days are over.