• Title/Summary/Keyword: asymmetry ratio

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Geosynchronous Magnetic Field Response to Solar Wind Dynamic Pressure

  • Park, Jong-Sun;Kim, Khan-Hyuk;Lee, Dong-Hun;Lee, En-Sang;Jin, Ho
    • Journal of Astronomy and Space Sciences
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    • v.28 no.1
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    • pp.27-36
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    • 2011
  • The present study examines the morning-afternoon asymmetry of the geosynchronous magnetic field strength on the dayside (magnetic local time [MLT] = 06:00~18:00) using observations by the Geostationary Operational Environmental Satellites (GOES) over a period of 9 years from February 1998 to January 2007. During geomagnetically quiet time (Kp < 3), we observed that a peak of the magnetic field strength is skewed toward the earlier local times (11:07~11:37 MLT) with respect to local noon and that the geosynchronous field strength is larger in the morning sector than in the afternoon sector. That is, there is the morning-afternoon asymmetry of the geosynchronous magnetic field strength. Using solar wind data, it is confirmed that the morning-afternoon asymmetry is not associated with the aberration effect due to the orbital motion of the Earth about the Sun. We found that the peak location of the magnetic field strength is shifted toward the earlier local times as the ratio of the magnetic field strength at MLT = 18 (B-dusk) to the magnetic field strength at MLT = 06 (B-dawn) is decreasing. It is also found that the dawn-dusk magnetic field median ratio, B-dusk/B-dawn, is decreasing as the solar wind dynamic pressure is increasing. The morning-afternoon asymmetry of the magnetic field strength appears in Tsyganenko geomagnetic field model (TS-04 model) when the partial ring current is included in TS-04 model. Unlike our observations, however, TS-04 model shows that the peak location of the magnetic field strength is shifted toward local noon as the solar wind dynamic pressure grows in magnitude. This may be due to that the symmetric magnetic field associated with the magnetopause current, strongly affected by the solar wind dynamic pressure, increases. However, the partial ring current is not affected as much as the magnetopause current by the solar wind dynamic pressure in TS-04 model. Thus, our observations suggest that the contribution of the partial ring current at geosynchronous orbit is much larger than that expected from TS-04 model as the solar wind dynamic pressure increases.

A Study of the Increasing Rate and the State of Sex Ratio in each Specific Fields of Medical Technicians in Korea (우리나라 의료기사 면허등록자의 증가현황 및 종별 의료기사의 성별비율 현황 조사연구)

  • Kwon, Soon-Seog;Han, Su-Jin
    • Journal of dental hygiene science
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    • v.6 no.2
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    • pp.65-77
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    • 2006
  • In this study, we surveyed the increasing rate of the licensed medical technicians from the year of 1970 to 2003 in Korea along with the investigation of the growth ratio by sex and fields among the licensed medical technicians. On the basis of this survey, this study aims to provide a milestone for the further studies to resolve the problems arising from asymmetry of sex ratio in some specific fields of medical technicians and oversupply of the in-service technicians. The results show that in contrast to the year 1970, the whole growth rate was 59.46%, males 28.98%, females 285.21%. In the case of sex ratio, in 1970 the figure of males to females was 6.63 to 1 but the figure of 2003 was 0.67 to 1, which indicates the number of female technicians are badly increasing. Until 2003, the ratio of female technicians was higher than the male technicians in the fields of medical technologists, physical therapists, dental hygienists, occupational therapists, medical record technicians but in radiologist technological, dental technicians and opticians the ratio was reversed.

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Analysis of Tidal Asymmetric Characteristics in the Muan Bay (무안만의 조석비대칭적 특성 분석)

  • Kang, Ju Whan;Kim, Yang Seon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.3
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    • pp.170-179
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    • 2020
  • Tidal asymmetry would occur owing to shallow water tides at the Western Coast of macro tidal area. Especially, as ebb dominance of Mokpo coastal zone is known as the most prominent in Korea, it had been studied by domestic researchers. The cause of ebb dominance in Mokpo area is considered due to extensive inter-tidal zone in Muan Bay, and this has been studied based on amplification ratio, relative phase and skewness of tide/tidal flow curves in order to analyze qualitative tidal asymmetry. Furthermore, it was possible to figure out tidal characteristics with the difference of tidal amplitude and phase with Mokpo Harbor by observing the tide for 15 days in Muan Bay, which showed 40 minutes shorter ebbing time than at Mokpo Harbor. In addition, tidal flow prediction data in Mokpo North Harbor and Mokpo-Gu were analyzed. Meanwhile, the basis regarding qualitative interpretation of bed sediment and suspended sediment was provided by examining the qualitative changes in tidal asymmetry for spring-neap tidal cycle through the PCA/SWA indices. In addition, by examining long-term changes of ebb dominance in Mokpo Port, tidal characteristics of the past, present and future in this area, which is related to tidal asymmetry, is also provided.

Electrical properties of multilayer piezoelectric transformer (적층압전변압기의 전기적 특성)

  • 정수태;조상희
    • Electrical & Electronic Materials
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    • v.9 no.2
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    • pp.138-145
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    • 1996
  • A multilayer piezoelectric transformer (MPT) which generates a high voltage dc power with low driving voltage and high voltage setup ratio was made by the tape casting method. The measured electrical characteristics of the MPT agreed with the results simulated from the equivalent circuit of the MPT. With increasing the number of layer in the MPT, the resonance curve of the input cur-rent revealed an asymmetry due to the increasing input capacitance, while that of output dc voltages revealed symmetry. The MPT which has very thin layer was excellently characterized as low driving voltage and high voltage setup ratio. The output dc voltage is nonlinearly influenced by the number of layer in the MPT.

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The Effects of Financial Support Policies on Corporate Decisions by SMEs

  • NAM, CHANGWOO
    • KDI Journal of Economic Policy
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    • v.38 no.3
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    • pp.79-106
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    • 2016
  • This paper investigates the effectiveness of public credit guarantee programs and interest-support programs for SMEs (small and medium enterprises). First, assuming that there is an imperfect information structure in the SME loan market, we analyze how SME support financial programs affect the corporate decisions made by SMEs with regard to default or loan sizes. In addition, this paper theoretically computes the optimal levels of credit guarantee amounts and the interest-support spread under equilibrium with imperfect information in a competitive loan market. Second, the paper empirically analyzes the continuous policy-treatment effect with the GPS (generalized propensity score) method. In particular, we consider the ratio of guaranteed debt to the total debt as a continuous policy treatment. The empirical results show that marginal effects of a credit guarantee on SMEs' productivity, profitability, and growth potential decrease with the ratio of guaranteed debt to the total debt. In addition, the average effect of a credit guarantee is maximized when this ratio is at 50% to 60%.

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Reaction of Ru(tpy)$Cl_3$ with N,N,C-Terdentates, 3,2'-Annulated-6-(2"-pyridyl)-2-phenylpyridines

  • 장영동;박재규
    • Bulletin of the Korean Chemical Society
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    • v.20 no.10
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    • pp.1200-1204
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    • 1999
  • The reactions of Ru(tpy)Cl3 (tpy = 2,2';6',2"-terpyridine) with new N,N,C-terdentate ligands, 3,2'-annulated-6-(2"-pyridyl)-2-phenylpyridines (1, HL) and the properties of their Ru(II) complexes are described. The distribution ratio of the two possible Ru(II) complexes, a pentaaza-coordinated complex [Ru(tpy)(1-N,N')Cl]+ and a cycloruthenated complex [Ru(tpy)(La-N,N',C)]+ are highly dependent on the length of the polymethylene unit. The trimethylene bridge of the N,N,C-terdentate in pentaaza-coordinated complex is rigid enough to induce an asymmetry in the complex.

Classification of Upper Body Somatotypes according to the Age Group : Using 3D-Body Scan Data

  • Na, Hyun-Shin
    • International Journal of Costume and Fashion
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    • v.5 no.1
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    • pp.1-13
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    • 2005
  • Two hundreds of female aged 19 years old and up were recruited to evaluate the postural changes and bilateral variation of asymmetry over age. To find out the differences among the age group, subjects were classified into 5 groups, early young age(19-29), late young age(30-39), early middle age(40-49), late middle age(50-59), and old age(60-). 35 body measurements were taken by the 3-D body scanner which allowed us to take measurements which cannot be measured using traditional methods, including the shape of a cross section, slice area surface are, and volume. Bilateral variations were observed as a function of age; Depth of scapular point level, scapular point to center back, and blade angle. Postural change of anterior cervical angle, upper anterior thoracic angle, upper posterior thoracic angle, posterior cervical angle, and center back/center front ratio were also exhibited. In each measurements, subjects were classified into normal, and abnormal group. Percentiles of abnormal in shoulder line angle, blade angle, neck point $\∼$ acromial point $\∼$ scapular point, posterior cervical angle, and upper posterior thoracic angle were increased over age group. The upper body of lateral view was classified into 3 types of posture based on the previous research; straight, erect(leaning back), and stooped(bent forward). The percentiles of subjects who have straight postures were decreased as a function of age, but those of stooped postures were increased. Subjects who have erect postures did not so. The stooped posture group shows the big cervical fossa angle, anterior cervical angle, posterior cervical angle, upper posterior thoracic angle, and the small upper anterior thoracic angle comparing to the straight and erect posture group. These results could be apply for clothing construction reflecting the changes in back, shoulder, neck, and the bilateral asymmetry according to the target age group.

Correlation among Conformation Parameters in 'Fuji' Apple Fruit ('후지' 사과 과실의 형태 결정 요인 간 상관)

  • Yoon, Tae-Myung;Han, Su-Gon;Park, Youn-Moon
    • Horticultural Science & Technology
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    • v.19 no.3
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    • pp.358-361
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    • 2001
  • Factors affecting fruit conformation of 'Fuji' apples (Malus domestica Borkh.) were investigated through correlation study of fruit weight, seed numbers, and seed weight in relation to fruit conformation indices. Apples were harvested from two orchards in 'Andong' and 'Youngyang' areas at commercial maturity and grouped by fruit weight. Average number of seeds and seed weight were 8.9 and 0.64 g in 'Andong' orchard, while 6.3 and 0.47 g in 'Youngyang' orchard, respectively. When pooled data from the both orchards were analyzed, correlation of fruit weight with seed weight was significantly positive, whereas that with seed number was not significant. Fruit shape index determined by length/diameter ratio was positively correlated with fruit weight, while relationship of the shape index with seed number or with seed weight was not significant. Asymmetry index tended to be low in apples from the 'Andong' orchard in which higher seed numbers and seed weight were observed. The asymmetry index showed highly negative correlations with seed numbers and with seed weight.

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The Nonlinear Equalizer for Super-RENS Read-out Signals using an Asymmetric Waveform Model (비대칭 신호 모델을 이용한 super-RENS 신호에서의 비선형 등화기)

  • Moon, Woosik;Park, Sehwang;Lee, Jieun;Im, Sungbin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.5
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    • pp.70-75
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    • 2014
  • Super-resolution near-field structure (super-RENS) read-out samples are affected by a nonlinear and noncausal channel, which results in inter-symbol interference (ISI). In this study, we investigate asymmetry or domain bloom in super-RENS in terms of equalization. Domain bloom is caused by writing process in optical recording. We assume in this work that the asymmetry symbol conversion scheme is to generate asymmetric symbols, and then a linear finite impulse response filter can model the read-out channel. For equalizing this overall nonlinear channel, the read-out signals are deconvolved with the finite impulse response filter and its output is decided based on the decision rule table that is developed from the asymmetry symbol conversion scheme. The proposed equalizer is investigated with the simulations and the real super-RENS samples in terms of raw bit error rate.

Influence of Parasitic Resistances and Transistor Asymmetries on Read Operation of High-Resistor SRAM Cells (기생저항 및 트랜지스터 비대칭이 고저항 SRAM 셀의 읽기동작에 미치는 영향)

  • Choi, Jin-Young;Choi, Won-Sang
    • Journal of IKEEE
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    • v.1 no.1 s.1
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    • pp.11-18
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    • 1997
  • By utilizing the technique to monitor the DC cell node voltages through circuit simulation, degradation of the static read operating margin In high load-resistor SRAM cell was examined, which is caused by parasitic resistances and transistor asymmetries in this cell structure. By selectively adding the parasitic resistances to an ideal cell, the influence of each parasitic resistance on the operating margin was examined, and then the cases with parasitic resistances in pairs were also examined. By selectively changing the channel width of cell transistors to generate cell asymmetry, the influence of cell asymmetry on the operating margin was also examined. Analyses on the operating margins were performed by comparing the supply voltage values at which two cell node voltages merge to a single value and the differences of cell node voltages at VDD=5V in the simulated node voltage characteristics. By determining the parasitic resistances and the transistor asymmetries which give the most serious effect on the static read-operation of SRAM cell from this analysis based on circuit simulated, a criteria was provided, which can be referred in the design of new SRAM cell structures.

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