• Title/Summary/Keyword: Range of variation

Search Result 3,245, Processing Time 0.037 seconds

Electron-excitation Temperature with the Relative Optical-spectrumIntensity in an Atmospheric-pressure Ar-plasma Jet

  • Han, Gookhee;Cho, Guangsup
    • Applied Science and Convergence Technology
    • /
    • v.26 no.6
    • /
    • pp.201-207
    • /
    • 2017
  • An electron-excited temperature ($T_{ex}$) is not determined by the Boltzmann plots only with the spectral data of $4p{\rightarrow}4s$ in an Ar-plasma jet operated with a low frequency of several tens of kHz and the low voltage of a few kV, while $T_{ex}$ can be obtained at least with the presence of a high energy-level transition ($5p{\rightarrow}4s$) in the high-voltage operation of 8 kV. The optical intensities of most spectra that are measured according to the voltage and the measuring position of the plasma column increase or decay exponentially at the same rate as that of the intensity variation; therefore, the excitation temperature is estimated by comparing the relative optical-intensity to that of a high voltage. In the low-voltage range of an Ar-jet operation, the electron-excitation temperature is estimated as being from 0.61 eV to 0.67 eV, and the corresponding radical density of the Ar-4p state is in the order of $10^{10}{\sim}10^{11}cm^{-3}$. The variation of the excitation temperature is almost linear in relation to the operation voltage and the position of the plasma plume, meaning that the variation rates of the electron-excitation temperature are 0.03 eV/kV for the voltage and 0.075 eV/cm along the plasma plume.

Monpe Workpants and Their Memetic Derivations

  • Rhew, Soohyeon;Ro, Juhyun;Yi, Jaeyoon
    • International Journal of Costume and Fashion
    • /
    • v.17 no.1
    • /
    • pp.73-87
    • /
    • 2017
  • Monpe, Korean women's wartime attire during the Japanese colonization period, has survived for 70 years as typical baggy workpants for rural women and emerged as retro-fashion. This paper applied a theory of "meme" to explain the monpe fashion trend in Korea. Based on literature review, empirical analyses were conducted by analyzing market and media including newspaper articles and blogs. We found that the monpe meme has evolved over time through variation, penetration, and diffusion. In terms of variation, the impression of monpe transitioned from a negative image to a positive one as a result of changes in design, functionality, and popular image. In terms of penetration, the monpe meme has spread into popular culture, again through mass media, with images of active, sexy, and attractive monpe-wearers on television and at popular occasions. Finally, the monpe meme has diffused throughout a broad range of consumers of various ages and both genders as an item of clothing for various occasions through diversified distribution channels. In this way, the development of monpe as fashionable clothing in Korea during the 2000s is itself a meme reflecting its evolution from a disgraceful colonial legacy to an item of contemporary fashion.

Seasonal Variation of Heat Content in the Neighbouring Seas of Korea (韓國 周邊 海洋 貯熱量의 秀節的 變動)

  • Gang, Yong-Gyun
    • 한국해양학회지
    • /
    • v.20 no.3
    • /
    • pp.1-5
    • /
    • 1985
  • Seasonal variations of heat content in the neighbouring seas of Korea are estimated from the bimonthly normals of seawater temperature in the upper 300m for 15 years (1961~1975) at 192 stations. The heat is seasonally stored mainly in the upper 100m layer in the East Sea and in the whole water column in the West and South Seas of Korea. The annual range of heat content changes in the West Sea is almost the same as that in the East Sea. The annual phase of heat content variation lags behind that of sea surface temperature variation by one to three months. Due to the seasonal advections of heat by currents and winds, the annual amplitude of heat storage rate in the neighbouring seas of Korea is much larger than that of incoming radiation.

  • PDF

A Study on the Uncertainty Estimation of Flowmeter Calibrator with Two Master Flowmeters (2개의 기준유량계를 이용한 유량계 교정장치의 측정불확도 평가에 관한 연구)

  • Choi Jong Oh;Lee Woan Kyu;Lim Ki Won
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.28 no.10
    • /
    • pp.1219-1230
    • /
    • 2004
  • Comparing to the gravimetric and volumetric method, the flowmeter calibration based on the master meter method is relatively economical and convenient, especially for high flowrate. The uncertainty of flow quantity and flowrate using the master meter method was evaluated according to the GUM (Guide to the Expression of Uncertainty in Measurement). In order to apply for the wider flow range, two master meters (electromagnetic flow meter) were employed as reference flowmeters. The uncertainty of the master meter was obtained by combining the statistical variation of the repeated measurements and the variation of fluid density and pipe material due to temperature and pressure changes were scrutinized. for a practical application, the uncertainty of calibrator, whose measuring capacity of 1000 ㎥/h obtained by employing two 500 ㎥/h electromagnetic How meters, was evaluated. The uncertainty budget shows the quantitative contribution of each uncertainty component to the overall uncertainty of the calibrator. As a result, it was found that the dominant uncertainties were from the master meter, which was evaluated statistically, and from the process of least squares fitting. On the contrary, the uncertainties arising from the variation of the fluid density and the pipe volume due to the temperature and pressure were negligible.

Impact of Upper Limb Joint Fluid Variation on Inflammatory Diseases Diagnosis

  • Hari, Krishnan G.;Ananda, Natarajan R.;Nanda, Anima
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.6
    • /
    • pp.2114-2117
    • /
    • 2014
  • Joint pain is generally a common disorder not only for the old aged people but also for the immunocompromised patients. The present proposed study reveals the presence of inflammatory diseases in joint generally diagnosed by removing synovial fluid and changes in the volume and composition are examined for the presence of WBC and crystals. This study implement a non-invasive approach to identify the changes in joint fluid by measuring the changes in electrical property of the synovial tissue under the influence of electrical current signal with frequency range between 100 kHz to 300 kHz. The response of tissue for the current signal was measured in terms of potential drop across the tissue. The hardware system design consists of input and output sections. The input section which applies current signal to upper limb joint region is made of ICL8038 function generator IC with amplifier and voltage to current converter. The output section picks voltage variation using metal surface electrode, amplifier, ADC, PIC microcontroller and LCD interface. 100 patient inclusive of normal and disease affected patients where examined for upper limb synovial fluid variation and inflammatory diseases were identified.

Analysis for the Fluctuation of the Photoplethysmographic Waveform derived by Temperature Stress of Measuring Position (측정부 온도 부하에 따른 광용적맥파 파형 요동 특성 분석)

  • Lee, Chungkeun;Shin, Hangsik
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.2
    • /
    • pp.304-309
    • /
    • 2015
  • Applicable range of Photoplethysmography (PPG) becomes wider as a non-invasive physiological measurement technique. However, PPG waveform is easy to be distorted by ambient light or vascular variation from temperature changes. Especially, irregular variation of PPG waveform caused by ambient temperature not only severely distorts the PPG, but also leads miss interpretation in clinical applications. Therefore, the investigation of between temperature and PPG waveform is quite important in using PPG. The purpose of this research is to quantify the PPG waveform characteristic and to investigate the waveform variation following the temperature change on measuring site. To quantify the fluctuation of PPG waveform, we use two techniques; detrended fluctuation analysis (DFA) and AC/DC analysis of PPG. We record PPG under temperature stress, which applied by medical use heat pack ($40^{\circ}C$) and ice pack ($0^{\circ}C$). Ten participants were applied to the experiment, and the result was evaluated to approve the temperature effect with statistical method, Wilcoxon signed rank test. The result shows that the AC component (p<0.05) and perfusion index DFS scale exponent (p<0.01) of PPG have the significance to temperature stress except for a DC component of PPG.

Study on the Plasma Oscillation for Gas Chromatographic detector (플라즈마진동을 이용한 기체크로마토그래프의 검출기에 대한 연구)

  • Kim, Hyo Jin;Mang, Dae Young;Kang, Jong Seong
    • Analytical Science and Technology
    • /
    • v.6 no.4
    • /
    • pp.369-374
    • /
    • 1993
  • Plasma oscillation has been observed during the development of the glow discharge as detector for gas chromatography. The variation of oscillation frequency shows the better stability and detection limits than the changes in the dischange curent. To investigate the range of useful operating conditions and to gain insight into the mechanism, the effect of experimental parameters on plasma oscillation have been studied. This study includes the variation of discharge current, pressure and discharge gap. Frequency ranges of 10KHz to 10MHz have been observed with the various shapes of oscillation. Two kinds of mode for oscillation are observed with the variation of electrode gap at low pressure and low voltage.

  • PDF

Variation of Kalosaponin Contents in Plant Parts and Population of Native Kalopanax septemlobus(Thunb.)Koidz (한국자생 음나무집단 및 채취부위에 따른 Kalosaponin 함량 변이)

  • Choi, Myung-Suk;Kwon, Ki-Won;Lee, Cheol-Ho
    • Korean Journal of Pharmacognosy
    • /
    • v.31 no.2
    • /
    • pp.203-208
    • /
    • 2000
  • The concentrations of 4 kalosaponins from tissues of Kalopanax septemlobus (Thunb.)Koidz grown in 7 provenances in Korea were determined by HPLC. Kalosaponin contents in plant part were much higher in the inner bark(30.59 mg/g on the dry weight basis) than those of young leaves(22.74 mg/g on the dry weight basis) and root bark(18.02 mg/g on the dry weight basis). A considerable range of variation in the contents was observed among population. The kalosaponin contents in inner bark from each population were highest in the Mt. Barwang (30.37 mg/g on the dry weight basis) followed by Mt. Gariwang, Hanra II, Mangun, Paltan, and Hanra I population. A variation of kalosaponin contents among population may be affected by both environmental and genetic factors. Establishment of selection and propagation of high kalosaponin containing trees can be a good source for the development of valuable forest products.

  • PDF

Variation of Water Temperature in Chungmu Port (충무항의 수온 변동)

  • Yeom, Mal-Gu;Kim, Sam-Gon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.20 no.2
    • /
    • pp.79-82
    • /
    • 1984
  • Seasonal and secular variations of water temperature in Chungmu port were investigated with the data obtained from the Technical Reports(1976~1983) of Hydrographic Office. Monthly and annual range of water temperature were 2 to 8$^{\circ}C$ and 18 to 21$^{\circ}C$, respectively. The coefficients of variance of monthly mean water temperature were 0.015(February, 1976) to 0.208(December, 1980) and their values were smaller in the summer season than in the winter season. The result of harmonic analysis for investigating the seasonal variation of water temperature was T(t)=15.66+8.06 cos(10$^{\circ}$t-233.5)+0.92 cos(20$^{\circ}$t-216). The periods of secular variation were about 2 years and 3 years.

  • PDF

Effect of Ultrasonic Frequency on the Atomization Characteristics of Single Water Droplet in an Acoustic Levitation Field (음향 부양장(acoustic levitation field)에서 초음파 주파수(ultrasonic frequency)에 따른 단일 액적의 미립화 특성)

  • Suh, Hyun Kyu
    • Journal of ILASS-Korea
    • /
    • v.18 no.3
    • /
    • pp.126-131
    • /
    • 2013
  • This paper describes the effect of ultrasonic frequency(f) on the atomization and deformation characteristics of single water droplet in an acoustic levitation field. To achieve this, the ultrasonic levitator that can control sound pressure and velocity amplitude by changing frequency was installed, and visualization of single water droplet was conducted with high resolution ICCD and CCD camera. At the same time, atomization and deformation characteristics of single water droplet was studied in terms of normalized droplet diameter($d/d_0$), droplet diameter(d) variation and droplet volume(V) variation under different ultrasonic frequency(f) conditions. It was revealed that increase of ultrasonic frequency reduces the droplet diameter. Therefore, it is able to levitate with low sound pressure level. It also induces the wide oscillation range, large diameter and volume variation of water droplet. In conclusion, the increase of ultrasonic frequency(f) can enhance the atomization performance of single water droplet.