• Title/Summary/Keyword: absorptive index

Search Result 14, Processing Time 0.021 seconds

The dielectric properties of triple SiO thin film using spectroscopic ellipsometer (Spectroscopic ellipsometer를 이용한 삼원 SiO박막의 증착조건에 따른 유전율 특성)

  • 김창석;황석영
    • Electrical & Electronic Materials
    • /
    • v.8 no.2
    • /
    • pp.129-135
    • /
    • 1995
  • SiO thin films are deposited by evaporator the refractive index of wave length, photon energy and the absorptive rate of these films are measured by spectroscopic ellipsometer. It is derived the absorptive rate and permitivity of SiO thin films from the equations that calculating the refractive index. And the result show good agreement with the calculated values and experimental values. As a result, the wave length of light is increased in the condition that the angle of incidence is fixed on SiO thin film, the basic absorption and the absorption impurities are found in the low wave length (below 450 nm in this study) and the reflective absorption and conductive absorption is increased by the form of exponential function over the low wavelength. The absorptive rate is increased by increased the angle of incidence and thickness of SiO film for the insulating layer. As the thickness of SiO film is increased, the value of complex permitivity is decreasing and as wave length of incidence is increased., the value of dielectric is linearly increasing.

  • PDF

Influences of Pretreatment Procedures, and Refractive and Absorptive Indices in Grain Size Analysis of Sandy Samples by Laser Diffraction Grain Size Analyzer (레이저 회절 입도분석기를 이용한 사질 시료의 입도분석에 있어서 전처리 및 굴절율과 흡수율의 영향)

  • Yoon, Soon-Ock;Hwang, Sangill;Park, Chung-Sun
    • Journal of the Korean Geographical Society
    • /
    • v.48 no.6
    • /
    • pp.819-836
    • /
    • 2013
  • This study aims to compare the inf luences of pretreatment procedures, and refractive and absorptive indices in grain size analysis of sandy samples collected from Sagot Beach, Baengnyeong Island by laser diffraction grain size analyzer, and propose the proper procedure and method in grain size analysis of sandy samples. The analyzed samples do not indicate large differences by the three pretreatment procedures applied in this study. However, the organic matters should be removed by hydrogen peroxide, because the samples without hydrogen peroxide pretreatments show differences from the samples with hydrogen peroxide pretreatments. The results with a refractive index of 1.3 and absorptive index less than 0.01 also indicate differences from those with other indices. Compared to the differences in fine samples, these differences are not significant and thus, it can be concluded that the results in grain size analysis of sandy samples are not greatly influenced by the refractive and absorptive indices. However, other indices out of the ranges should be applied.

  • PDF

PHASE VARIATION IN DOPPLER SIGNAL FOR VARIOUS OPTICAL PARAMETERS

  • Son, Jung-Young;Kim, Myung-Sik;Oh, Myung-Kwan
    • Proceedings of the KIEE Conference
    • /
    • 1989.07a
    • /
    • pp.629-632
    • /
    • 1989
  • The scattered light intensity from a spherical particle passing through the cross-over region of two coherent laser beams, varies periodically. Photodetection of this light beams produces a periodic signal of varying amplitude. The phase of the signal varies with the particle size and refractive index, the beam crossing angle and wavelength, and the position and size of the scattered ligth collecting aperture. In this paper the phase variation with respect to the particle absorptive index of retraction, collecting lens size and beam crossing angle is calculated using both Mie scattering theory and reflection theory. The two theories show good agreement in phase predictions, especially for large absorptive indices and for small collection lenses. Both theories predict phase to be inversely proportional to the beam crossing angle.

  • PDF

Optimization of Grating Structures in Complex-Coupled MQW DFB Lasers with Absorptive Gratings (흡수 회절격자를 가지는 복소결합 다중양자우물 DFB 레이저의 회절격자 구조의 최적화)

  • Cho, Sung-Chan;Lee, Dong-Chan;Kim, Boo-Gyoun
    • Journal of the Korean Institute of Telematics and Electronics D
    • /
    • v.36D no.7
    • /
    • pp.80-91
    • /
    • 1999
  • We present various optimal grating structures which give the low threshold gain, good modulation characteristics, small effective linewidth enhancement factor, and large fabrication tolerance in complex-coupled MQW DFB lasers with absorptive gratings. To obtain these, we calculate the complex coupling coefficients using the extended additional layer method and the threshold gain including the modal loss in the absorptive grating region for rectangular and trapezoidal gratings. Based on the comparison of the results for various possible absorptive grating structures, the design guidelines are presented to obtain the low threshold gain or large fabrication tolerance. Among the grating structures studied, the double grating structure consisting of the absorptive grating on the index grating has the largest fabrication tolerance for the threshold gain and the coupling strength. The fabrication tolerance for the coupling ratio is very large for all the grating structures studied.

  • PDF

Comparison of Acoustic Performance Depending on the Location of Sound Absorptive and Diffuser in Small Auditoriums Using 1/10 Scale Models (1/10 축소모형을 이용한 소공연장의 흡음재와 확산체의 적용위치에 따른 음향성능 비교)

  • Kim, Tae-Hee;Park, Chan-Jae;Park, Ji-Hoon;Haan, Chan-Hoon
    • The Journal of the Acoustical Society of Korea
    • /
    • v.34 no.2
    • /
    • pp.146-156
    • /
    • 2015
  • This study investigated how the location of sound absorptive materials and sound diffusers affects the acoustic performance of small auditoriums. It was conducted for a standard model established with the averaged dimension of 36 auditoriums which had opened since 2000 in Daehak-ro, Seoul. In this study, the installation area of finishing materials was calculated upon a back wall which had the smallest installation effective area of finishing materials. To analyze the changes of acoustic performance according to installation location of finishing materials, experiments were carried out using the 1/10 down scale models for 8 cases which were made by classifying the installation location of ceiling and side wall into the front, middle and rear part.The used acoustic parameters were reverberation time (RT), early decay time (EDT), clarity (C80), definition (D50) and speech transmission index (STI). In result, the index related to the amount of reverberant sound (RT, EDT) showed the great changes when evaluating it through just noticeable difference (JND), but the one related to clarity (C80, D50, STI) hardly indicated the changes. In case to obtain short reverberation time, it was most effective to control reverberation time through the side walls when installing sound absorptive and diffusive materials, and side wall front was the location which could get the shortest reverberation time.

A Study on the cooperation activation among business: Focused on Leadership, Absorptive Capacity (기업 간 협업 활성화 방안에 대한 연구 : 리더십과 흡수역량을 중심으로)

  • Jeun, Hyang-Ok;Hyun, Byung-Hwang
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.10
    • /
    • pp.189-198
    • /
    • 2016
  • In recent years, the global financial crisis has worsened the economic environment for small and medium-sized businesses. A great number of South Korean enterprises are having various managerial difficulties, such as insufficient funds, shortage of manpower and lack of market information. To overcome these difficulties, many experts have suggested plans to encourage cooperation among small businesses, and such cooperation has provided diverse services to complement the insufficient capabilities of the individual companies. In spite of the efforts made by government to incite cooperation, however, the businesses themselves have displayed a lack of willingness to such cooperation. Cooperation requires a series of complicated and interdependent processes and, thus, governmental support alone cannot guarantee the necessary willingness to cooperate among small businesses. This research empirically analyzed how cooperative and creative leaderships influence the willingness to cooperate among corporate members. We also empirically studied how relationships among corporate members vary in accordance with their absorptive capacity.

Fuzzy-AHP-Based Technology Evaluation Model for venture firms (Fuzzy-AHP에 기반을 둔 벤처기업의 기술력 평가 모델)

  • Joun, Hyang-Soon;Lee, Sang-Yong
    • Journal of Digital Convergence
    • /
    • v.14 no.7
    • /
    • pp.363-371
    • /
    • 2016
  • Technology evaluation for technology innovation of venture firms should take the rapidly changing corporate environment, the ambiguity of language used in evaluation, and the inaccuracy of evaluation index into consideration. In this paper, targeting the absorptive capacity and technological entrepreneurship which are typical evaluation factors of venture firms, an ACTEM model to calculate the importance, priority, and dynamic capability of factors, applying Fuzzy-AHP was proposed. The fuzzy theory was introduced to compensate for the ambiguity of cognitive judgments when calculating weighted values for the factors that made up an assessment scale. An assessment criteria framework for absorptive capacity, technological entrepreneurship, and dynamic capability, which were not considered in previous studies on the evaluation and measurement of technological prowess, so that the users could have a realistic alternative to choose. The study compared the ACTEM model with the old AHP assessment method and found that "knowledge acquisition" and "producing ability" were the highest in absorptive capacity and technological entrepreneurship, respectively, thus demonstrating its validity.

Corticosterone Administration Alters Small Intestinal Morphology and Function of Broiler Chickens

  • Hu, Xiaofei;Guo, Yuming
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.12
    • /
    • pp.1773-1778
    • /
    • 2008
  • Two experiments were carried out to study the effects of corticosterone (CORT) administration on intestinal morphology and function of broilers. In both experiments, birds were randomly divided into two equal groups. One group was the control group (CTRL), and the birds were fed with a basal diet. The other was the experimental group (CORT), and the birds were fed with the basal diet plus 30 mg of CORT/kg diet. At 21 days of age, performance, morphological characteristics of intestine, D-xylose level in plasma, activities of digestive enzymes in digesta, digestibility of nutrients and 5-bromo-2-deoxyuridine (BrdUrd)-labeling index of intestinal epithelial cells were determined. CORT administration decreased feed intake, daily gain and feed conversion ratio (p<0.05). CORT also decreased duodenal and jejunal villus height (p<0.05) as well as crypt depth (p<0.05). The D-xylose level in plasma of CORT-treated broilers was lower than that of the control (p<0.05). CORT treatment caused a decrease in apparent digestibility of protein (p<0.05), whereas fat and starch apparent digestibilities were unaffected (p>0.05). CORT administration increased activities of trypsin and amylase (p<0.05), and decreased BrdUrd-labeling index of duodenal and jejunal epithelial cells (p<0.05). In conclusion, CORT administration impaired the normal morphology and absorptive capacity of the small intestine of broiler chickens.

Researches on Diagnostic Indices of Skin Diseases Based on Concepts of Interstices (주리개념(腠理槪念)에 근거한 피부과 질병의 진단지표 기초연구)

  • Chi, Gyoo Yong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.27 no.2
    • /
    • pp.167-172
    • /
    • 2013
  • In order to establish the diagnostic indices of skin diseases, some physiological and pathological concepts of interstices(腠理) were researched based on , and western dermatology with etymological analysis. As physiological indices for diagnosis of skin diseases, measurement of epidermis and dermis using ultrasonogram in the zhongwan and dachui's location. And for grading looseness and fineness of interstices with 3 unsound groups, measuring numbers and sizes of sweat pores in each point's 1 cm diameter circular area using comparative method and palpation assessment. Another index is superficial temperature. As pathological indices for diagnosis, validating volumes of dead skin cells and grading degrees of atrophy and degeneration of skin lesion. And as supplementary measures, absorptive degrees of cosmetics on face should be recorded according to 3 grades. These diagnostic indices can contribute to establishment of standard pattern identification and prescription of skin diseases through converting anatomical cognizance into classical concepts of interstices objectively.

Detection of Yellow Sand Dust over Northeast Asia using Background Brightness Temperature Difference of Infrared Channels from MODIS (MODIS 적외채널 배경 밝기온도차를 이용한 동북아시아 황사 탐지)

  • Park, Jusun;Kim, Jae Hwan;Hong, Sung Jae
    • Atmosphere
    • /
    • v.22 no.2
    • /
    • pp.137-147
    • /
    • 2012
  • The technique of Brightness Temperature Difference (BTD) between 11 and $12{\mu}m$ separates yellow sand dust from clouds according to the difference in absorptive characteristics between the channels. However, this method causes consistent false alarms in many cases, especially over the desert. In order to reduce these false alarms, we should eliminate the background noise originated from surface. We adopted the Background BTD (BBTD), which stands for surface characteristics on clear sky condition without any dust or cloud. We took an average of brightness temperatures of 11 and $12{\mu}m$ channels during the previous 15 days from a target date and then calculated BTD of averaged ones to obtain decontaminated pixels from dust. After defining the BBTD, we subtracted this index from BTD for the Yellow Sand Index (YSI). In the previous study, this method was already verified using the geostationary satellite, MTSAT. In this study, we applied this to the polar orbiting satellite, MODIS, to detect yellow sand dust over Northeast Asia. Products of yellow sand dust from OMI and MTSAT were used to verify MODIS YSI. The coefficient of determination between MODIS YSI and MTSAT YSI was 0.61, and MODIS YSI and OMI AI was also 0.61. As a result of comparing two products, significantly enhanced signals of dust aerosols were detected by removing the false alarms over the desert. Furthermore, the discontinuity between land and ocean on BTD was removed. This was even effective on the case of fall. This study illustrates that the proposed algorithm can provide the reliable distribution of dust aerosols over the desert even at night.