• Title/Summary/Keyword: Length dependence

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Dependence of Self-heating Effect on Width/Length Dimension in p-type Polycrystalline Silicon Thin Film Transistors

  • Lee, Seok-Woo;Kim, Young-Joo;Park, Soo-Jeong;Kang, Ho-Chul;Kim, Chang-Yeon;Kim, Chang-Dong;Chung, In-Jae
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.505-508
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    • 2006
  • Self-heating induced device degradation and its width/length (W/L) dimension dependence were studied in p-type polycrystalline silicon (poly-Si) thin film transistors (TFTs). Negative channel conductance was observed under high power region of output curve, which was mainly caused by hole trapping into gate oxide and also by trap state generation by self-heating effect. Self-heating effect became aggravated as W/L ratio was increased, which was understood by the differences in heat dissipation capability. By reducing applied power density normalized to TFT area, self-heating induced degradation could be reduced.

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A Study on Radition-Induced Current in Insulating Oil during X-ray Irradiation (방사선(放射線) 조사(照射) 중(中) 절연유(絶緣油)의 유기전류(誘起電流)에 관한 연구(硏究))

  • Kim, Young-Il;Lee, Duck-Chool;Chung, Yon-Tack
    • Journal of radiological science and technology
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    • v.11 no.1
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    • pp.33-41
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    • 1988
  • This study was measured the radiation-induced current - X-ray dose, dose rate, X-ray quality, time, temperature, electric field characteristics and the dependence of gap length in insulating oil under of D.C. Voltage before, during and after X-ray irradiation. The obtained results can be summarized as following. 1. The radiation - induced current is more the dependence of X-ray quality (tube voltage) than quantity (tube current), the dependence of quantity is appeared at the high than low X-.ay tube voltage. 2. The dependence of dose rate is appeared at the more dose rate, and ${\triangle}\;=\;0.64{\sim}0.74$. 3. The higher temperature of insulating oil and X-ray tube voltage (X-ray quality) is increased, at the low electric field, the more radiation-induced current. 4. $G_{eq}-G_{o}(={\triangle}G)$ is increased at the low than high temperature, high than low X-ray quality. 5. The dependence of temperature is appeared before than during X-ray irradiation. 6. The RIC saturation region is appeared at the high than low insulating oil temperature during (1000 V/cm above) than before (4000 V/cm above) X-ray irradiation.

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Fish length dependence of target strength for black rockfish, goldeye rockfish at 70kHz and 120kHz (70kHz 및 120kHz에 있어서 조피볼락, 불볼락에 대한 반사강도의 체장 의존성)

  • Mun, Jae-Ho;Lee, Dae-Jae;Shin, Hyeong-Il;Lee, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.1
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    • pp.30-37
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    • 2006
  • Black rockfish and goldeye rockfish are commercially important fish species due to the increasing demand in Korea. When estimating the abundance of stocks for these species acoustically, it is of crucial importance to know the target strength(TS) to length dependence. In relation to these needs, TS measurement was conducted on black rockfish and goldeye rockfish in an acrylic salt water tank using 70kHz and 120kHz split beam echo sounders. The TS for these two species under the controlled condition was simultaneously measured with the swimming movement by DVR system and analyzed as a function of fish length(L). The results obtained are summarized as follows: The best fit regression of TS on fish length of black rockfish was TS=19.38 Log(L, cm)-70.46 ($r^2=0.71$) at 70kHz and TS=22.39 Log(L, cm)-70.40 ($r^2=0.64$) at 120kHz and in the standard form TS=20 Log(L, cm)-71.29 ($r^2 = 0.70$) at 70kHz and TS=20 Log(L, cm)-66.88 ($r^2=0.57$) at 120kHz. The best fit regression of TS on fish length of goldeye rockfish was TS=17.10 Log(L, cm)-68.28 ($r^2=0.37$) at 70kHz and TS=24.39 Log(L, cm)-73.74 ($r^2=0.59$) at 120kHz and in the standard form TS=20 Log(L, cm)-72.03 ($r^2=0.32$) at 70kHz and TS=20 Log(L, cm)-67.68 ($r^2=0.64$) at 120kHz. An empirical model for fish TS(dB) averaged over the dorsal aspect of 115 fishes of black rockfish and goldeye rockfish and which spans the fish length(L, m) to wavelength($\lambda$, m) ratio between 8 and 30 was derived : TS=34.12 Log(L)-14.12 Log($\lambda$)-23.83, ($r^2=0.90$).

A study on the electromigration phenomena in Al-1%Si thin film interconnections with Ti underlayers (Ti underlayer를 갖는 AI-1%Si 박막배선에서의 일렉트로마이그레이션 현상에 관한 연구)

  • 유희영;김진영
    • Journal of the Korean Vacuum Society
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    • v.8 no.1
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    • pp.31-35
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    • 1999
  • In this paper, the lifetime dependence as a function of the line length of Al-1%Si thin film interconnections due to electromigration in semiconductor devices was studied. Al-1%Si thin film interconnections with a pattern of straight type were formed by using a standard photolithography process. The test patterns manufactured have line lengths in the range of 100 to 1600 $mu extrm{m}$. Al-1%Si thin film interconnections with Ti underlayers showed longer lifetime than those without Ti underlayers. Ti underlayers are believed to improve electromigration resistance resulting in a longer lifetime in Al-1%Si thin film interconnections. The dependence of lifetime on the line length in Al-1%Si/Ti thin film interconnections shows a saturation tendency near 800 $\mu\textrm{m}$ line length.

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A Classifier for Textured Images Based on Matrix Feature (행렬 속성을 이용하는 질감 영상 분별기)

  • 김준철;이준환
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.3
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    • pp.91-102
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    • 1994
  • For the analysis of textured image, it requires large storage space and computation time to calculate the matrix features such as SGLDM(Spatial Gray Level Dependence Matrix). NGLDM(Neighboring Gray Level Dependence Matrix). NSGLDM(Neighboring Spatial Gray Level Dependence Matrix) and GLRLM(Gray Level Run Length Matrix). In spite of a large amount of information that each matrix contains, a set of several correlated scalar features calculated from the matrix is not sufficient to approximate it. In this paper, we propose a new classifier for textured images based on these matrices in which the projected vectors of each matrix on the meaningful directions are used as features. In the proposed method, an unknown image is classified to the class of a known image that gives the maximum similarity between the projected model vector from the known image and the vector from the unknown image. In the experiment to classify images of agricultural products, the proposed method shows good performance as much as 85-95% of correct classification ratio.

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Fish length dependence of acoustic target strength for 12 dominant fish species caught in the Korean waters at 75 kHz (한국 연근해에서 어획된 주요 12어종의 75 kHz에 대한 음향 반사 강도의 체장 의존성)

  • Lee, Dae-Jae
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.4
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    • pp.296-305
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    • 2005
  • Acoustic target strength (TS) of 12 commercially important fish species caught in the Korean waters had been investigated and their results were presented. Laboratory measurements of target strength on 12 dominant fish species were carried out at a frequencies of 75 kHz by single beam method under the controlled condition of the water tank with the 241 samples of dead and live fishes. The target strength pattern on individual fish of each species was measured as a function of tilt angle, ranging from $-45^{\circ}$ (head down aspect) to $45^{\circ}$ (head up aspect) in $0.2^{\circ}$ intervals, and the averaged target strength was estimated by assuming the tilt angle distribution as N ($-5.0^{\circ}$, $^15.0{\circ}$). The 75 to fish length relationship for each species was independently derived by a least - squares fitting procedure. Also, a linear regression analysis for all species was performed to reduce the data to a set of empirical equations showing the variation of target strength to fish length and fish species. An empirical model for fish target strength(TS, dB) averaged over the dorsal aspect of 158 fishes of 7 species and which spans the fish length(L, m) to wavelength(${\lambda}$, m) ratio between 6.2 and 21.3 was derived: TS: 27.03 Log(L)-7.7Log(${\kanbda}$)-17.21, ($r^2$=0.59).

A Reexamination of the Method of Measuring Internal Loss and Quantum Efficiency in Laser Diodes (레이저 다이오드의 내부손실 및 내부 양자효율 측정법에 대한 재고찰)

  • 한영수;도만희;김상배;정상구
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.5
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    • pp.121-125
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    • 1994
  • We examine the conventional method of measuring the internal optical loss using the dependence of the reciprocal external quantum efficiency on the cavity length in laser diodes. It is shown that the implicit assumption of constant internal differential quantum efficiency ${\eta}_{id}$, which has been customarily misinterpreted as internal quantum efficiency ${\eta}_{i}$, is not valid for devices with short cavity length. Therefore, for reliable measurments long cavity data should be used.

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Determination of Reorganization Energy from the Temperature Dependence of Electron Transfer Rate Constant for Hydroquinone-tethered Self-assembled Monolayers (SAMs)

  • Park, Won-choul;Hong, Hun-Gi
    • Bulletin of the Korean Chemical Society
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    • v.27 no.3
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    • pp.381-385
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    • 2006
  • The temperature dependence on the electron transfer rate constant $(k_{app})$ for hydroquinone redox center in $H_2Q(CH_2)_n$SH-SAMs (n = 1, 4, 6, 8, 10, and 12) on gold electrode was investigated to obtain reorganization energy $(\lambda)$ using Laviron’s formalism and Arrhenius plot of ln $[k_{app}/T^{1/2}]$ vs. T^{-1} based on the Marcus densityof-states model. All the symmetry factors measured for the SAMs were relatively close to unity and rarely varied to temperature change as expected. The electron tunneling constant $(\beta)$ determined from the dependence of the $k_{app}$ on the distance between the redox center and the electrode surface gives almost the same $\beta$ values which are quite insensitive to temperature change. Good linear relationship of Arrhenius plot for all $H_2Q(CH_2)_n$SH-SAMs on gold electrode was obtained in the temperature range from 273 to 328 K. The slopes n Arrhenius plot deduced that $\lambda$ of hydroquinone moiety is ca. 1.3-1.4 eV irrespectively of alkyl chain length of the electroactive SAM.

A Study on the Extraction of Mobility Reduction Parameters in Short Channel n-MOSFETs at Room Temperature (상온에서 짧은 채널 n-MOSFET의 이동도 감쇠 변수 추추에 관한 연구)

  • 이명복;이정일;강광남
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.9
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    • pp.1375-1380
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    • 1989
  • Mobility reduction parameters are extracted using a method based on the exploitatiion of Id-Vg and Gm-Vg characteristics of short channel n-MOSFETs in strong inversion region at room temperature. It is found that the reduction of the maximum field effect mobility, \ulcornerFE,max, with the channel length is due to i) the difference between the threshold voltage and the gate voltage which corresponds to the maximum transconductance, and ii) the channel length dependence of the mobility attenuation coefficient, \ulcorner The low field mobility, \ulcorner, is found to be independent of the channel length down to 0.25 \ulcorner ofeffective channel length. Also, the channel length reduction, -I, the mobility attenuation coefficient, \ulcorner the threshold voltage, Vt, and the source-drain resistance, Rsd, are determined from the Id-Vg and -gm-Vg characteristics n-MOSFETs.

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