• 제목/요약/키워드: Break index

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Luminosity function and size distribution of HII regions in M51

  • Lee, Jong-Hwan;Lee, Myung-Gyoon
    • The Bulletin of The Korean Astronomical Society
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    • 제36권2호
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    • pp.54.2-54.2
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    • 2011
  • We present a study of HII regions in M51 using HST/ACS images taken as part of the Hubble Heritage Program. We found about 19,600 HII regions in M51 with $H_{\alpha}$ luminosity in the range of $L=10^{35.5}-10^{39.0}\;erg\;s^{-1}$. The $H_{\alpha}$ luminosity function of HII regions (HII LF) in M51 is well represented by a double power law with its index ${\alpha}=-2.25{\pm}0.02$ for the bright part and ${\alpha}=-1.42{\pm}0.01$ for the faint part, separated at a break point $L=10^{37.1}\;erg\;s^{-1}$. Comparison with simulated HII LFs suggests that this break is caused by the transition of HII region ionizing sources, from low-mass clusters (including several OB stars) to more massive clusters (including several tens of OB stars). The HII LFs with L < $10^{37.1}\;erg\;s^{-1}$ are found to have different slopes for different parts in M51: the HII LF for the interarm region is steeper than those for the arm and the nuclear regions. This observed difference in HII LFs can be explained by evolutionary effects: HII regions in the interarm region are relatively older than those in the other parts of M51. The size distribution of the HII regions is fitted by a double power law with a break at D = 30 pc. The power law index for the small HII regions with 15 pc < D < 30 pc is ${\alpha}=-1.78{\pm}0.04$, whereas ${\alpha}=-5.04{\pm}0.08$ for the large HII region with 30 pc < D < 110 pc. The power law indices of the size distribution are related with those of HII LF, and the relation between the luminosities and sizes of HII regions is fitted well by $L{\propto}D^{3.04{\pm}}$.

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Application of Risk Indexes for Classifying Vulnerable Zone and Planning Structural Alternative in Preparation for Debris Flow Disaster (토사재해 취약 지역 분류 및 구조적 대안 수립을 위한 위험지표 적용)

  • Oh, Seung Myeong;Song, Chang Geun;Jung, Min Hyung;Seong, Joo-Hyun
    • Journal of the Korean Society of Safety
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    • 제32권3호
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    • pp.112-116
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    • 2017
  • This study applied risk indexes to the disaster flow event occurred at Mt. Umyeon region in 2011. A 2D hydrodynamic model was employed to calculate flow characteristics, and the model was validated against two dam break flow problems conducted by Bellos and EU CADAM project. The model performance was shown to be satisfactory. In order to determine which index is more appropriate to assess the vulnerability of debris flow, 3 risk indexes (FII, FHR and VDI) were considered. It was found that VDI, which determines the risk level only by the velocity factor, consistently predicted the risk level corresponding to 6 because the velocity range was widely organized. However, in the case of FII and FHR, the risk was reasonably quantified due to combined consideration of significant factors of flow velocity and debris thickness. Therefore, FII and FHR are expected to be more accurate than VDI. However, two indexes still need to be improved to include major factors such as debris density or material properties.

The Effects of Auricular Acupressure Therapy on Middle-aged and Old Adults' Dry Eye Syndrome (이압요법이 중·노년의 안구건조증에 미치는 효과)

  • Choi, Yun-Joo;Hwang, Sun-Kyung;Kim, Sang-Sik
    • Journal of East-West Nursing Research
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    • 제26권1호
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    • pp.17-27
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    • 2020
  • Purpose: This study aimed to examine the effect of auricular acupressure therapy on reducing the ocular symptoms and signs for dry eye syndrome. Methods: The participants who were aged ≥ 40 years old and met the inclusion criteria of the ocular surface disease index score ≥ 13 and a tear film break-up time ≤ 10 seconds were enrolled into the two groups: experimental group (n=29) and control group (n=27). Experimental group received auricular acupressure therapy for 8 weeks. Seed stickers were applied to the eye, liver and tubercle point of each ear once a week. Data were collected at pre and 4 and 8 weeks after the treatment and analysed the efficacy of intervention by repeated measures ANOVA. Results: There were significant differences in the ocular surface disease index, standard patient evaluation of eye dryness and a tear film break-up time in both eyes at 8 weeks after the treatment between the two groups. Conclusion: The findings indicate that the auricular acupressure therapy may be helpful for relieving symptoms of dry eye as a nursing intervention. In addition, it could also be utilized as a self-care practice using proper education and training.

Physicochemical Changes in UV-Exposed Low-Density Polyethylene Films

  • Salem, M.A.;Farouk, H.;Kashif, I.
    • Macromolecular Research
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    • 제10권3호
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    • pp.168-173
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    • 2002
  • Unstabilized low-density polyethylene (LDPE) films and films formulated with hindered amine light stabilizer (HALS) were exposed to UV-radiation; and the physicochemical changes during photooxidation processes have been investigated using tensile, FTIR spectre-photometric and thermal analytical (DSC) techniques. The dependence of tensile properties (elongation- and stress-at-break), carboxyl index and heat of fusion on UV-irradiation time have been discussed. The use of HALS is found to be effective in maintaining the UV-mechanical properties of the LDPE films. The experimental results showed that there exists no correlation between mechanical properties and carbonyl index, whereas crystallinity correlates well with carbonyl index in unstabilized and stabilized films for irradiation times greater than 100 h. The rate of formation of carbonyl groups is found to be dependent on UV exposure time. Crystallinity of the film samples is strongly influenced by both exposure time and presence of HALS.

Prediction of Break Indices in Korean Read Speech (국어 낭독체 발화의 운율경계 예측)

  • Kim Hyo Sook;Kim Chung Won;Kim Sun Ju;Kim Seoncheol;Kim Sam Jin;Kwon Chul Hong
    • MALSORI
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    • 제43호
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    • pp.1-9
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    • 2002
  • This study aims to model Korean prosodic phrasing using CART(classification and regression tree) method. Our data are limited to Korean read speech. We used 400 sentences made up of editorials, essays, novels and news scripts. Professional radio actress read 400sentences for about two hours. We used K-ToBI transcription system. For technical reason, original break indices 1,2 are merged into AP. Differ from original K-ToBI, we have three break index Zero, AP and IP. Linguistic information selected for this study is as follows: the number of syllables in ‘Eojeol’, the location of ‘Eojeol’ in sentence and part-of-speech(POS) of adjacent ‘Eojeol’s. We trained CART tree using above information as variables. Average accuracy of predicting NonIP(Zero and AP) and IP was 90.4% in training data and 88.5% in test data. Average prediction accuracy of Zero and AP was 79.7% in training data and 78.7% in test data.

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Variation of Grain Quality of Rice Varieties Grown at Different Locations I. Locational Variation of Quality-related Characteristics of Rice Grain (벼품종의 재배지역에 따른 미질특성변이 I. 미질특성의 지역변이)

  • Kwang-Ho Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • 제35권1호
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    • pp.34-43
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    • 1990
  • Six commerical rice varieties were cultivated and harvested at different locations in 1987 and 1988 to clarify the degree of locational variations. of several characteristics related to rice grain quality using the rice samples harvested from 8 to 20 locations for a variety each year. Locational variations of percent brown rice, percent milled rice, 1000-grain weight and amylose content were small, but whole grain rate, alkali digestibility, gel consistency, percent white-center and white-belly grain, degree of chalkiness and degree of translucency showed larger variations between locations. The degree of locational variation of sensory evaluation score for eating quality of cooked rice were varied from small to large along with rice variety used and year cultivated. Texture palatability index and stickiness of cooked rice among rheogram characteristics showed larger locational variations, but cohesiveness and springiness showed smaller variations between locations. Set back, break down and maximum viscosity showed larger locational variations among amylogram characteristics of rice flour. Special attention was given to a cultivated location, Anseong, because rice samples harvested at Anseong showed lower percent white-center and white-belly grain, and low set back and high break down in Chucheongbyeo, lower percent white-center and white-belly grain, higher texture palatability index and viscousness/hardness ratio, and low set back and high break down in Dongjinbyeo, higher texture palatability index, and low set back and high break down in Yongmunbyeo, lower percent white-center and white-belly grain in Sangpungbyeo, and low set back and high break down in Samkangbyeo. No other locations in this study produced rice samples showing wide acceptable quality-related characteristics except Anseong.

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Prosodic Break Index Estimation using LDA and Tri-tone Model (LDA와 tri-tone 모델을 이용한 운율경계강도 예측)

  • 강평수;엄기완;김진영
    • The Journal of the Acoustical Society of Korea
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    • 제18권7호
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    • pp.17-22
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    • 1999
  • In this paper we propose a new mixed method of LDA and tri-tone model to predict Korean prosodic break indices(PBI) for a given utterance. PBI can be used as an important cue of syntactic discontinuity in continuous speech recognition(CSR). The model consists of three steps. At the first step, PBI was predicted with the information of syllable and pause duration through the linear discriminant analysis (LDA) method. At the second step, syllable tone information was used to estimate PBI. In this step we used vector quantization (VQ) for coding the syllable tones and PBI is estimated by tri-tone model. In the last step, two PBI predictors were integrated by a weight factor. The proposed method was tested on 200 literal style spoken sentences. The experimental results showed 72% accuracy.

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Pot Life Assessment and Mechanical Property of Fast Curing Polyurethane Developed with Eco-friendly Pre-polymer

  • Joseph, Jessy;Moon, Junho;Kong, Tae Woong;Kim, Dong Ho;Oh, Jeong Seok
    • Elastomers and Composites
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    • 제55권1호
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    • pp.13-19
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    • 2020
  • 4,4'-Methylenebis(2-chlorobenzenamine) (MOCA)-free fast curing polyurethanes were prepared. In this study, the processibility of a fast curing polyurethane system was characterized by assessing the pot life. The obtained pot life of the polyurethane was 6-8 s, indicating that this prepolymer-curative system is appropriate for ribbon flow casting. The influence of the NCO index on the viscosity and mechanical properties was evaluated. The viscosity, tensile strength, tear strength, and hardness of the as-prepared polyurethanes showed an increasing trend, with an increase in the NCO index, whereas the elongation at break increased initially and then decreased with an increase in the NCO index. The gel fraction and crosslink density showed a direct correlation with the NCO index, which substantiated the improved mechanical properties at the higher NCO index. The coefficients of friction and abrasion deteriorated with an increase in the NCO index.

The Research on the Cost Analysis of the Abalone Aquacultural Management in Korea (전복 양식업의 경영비 분석과 정책 시사점 연구)

  • Ock, Young-Soo
    • The Journal of Fisheries Business Administration
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    • 제46권2호
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    • pp.13-29
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    • 2015
  • The abalone aquaculture has been very rapidly developed in Korea. Annual production quantity was less 200 tons before 2000th, it have been increased to over 9,000 tons in 2014. Also Abalone export amounts have been over 20 million dollars. The reason of rapid growth of Abalone aquaculture in Korea is due to high level profit ratio. Then now many fishing officers and other aquaculture fishers want to participate with abalone aquaculture newly. However Recent Abalone aquaculture in Korea is faced some problems. Aspects of production environmental status of fishing grounds are more aggravate, and then abalone aquaculture is exposed to various disease, and death rate of young abalone is higher. And aspect of management, the aquaculture cost is more increase. The demand of abalone also is depressing recently, this cause to come down the production price. In this viewpoint, Management analysis of abalone aquaculture in Korea is helpful for decision making of general aquaculture fisher want to participate newly. The analysis is practiced two aspects. One is index analysis, and the other is Break-even-point(BEP) analysis. The result of index analysis, average net profit rate has shown 28.0%, however the Regional difference has excessive. That is, Wando(major) has shown 39.4%, and Haenam province has shown 14.2%. On the other hand, the more scale has shown higher profit rate by aquaculture scale. And the result of BEP analysis, average has shown 93 cage number per abalone aquaculture household, and Wando(major) has shown 56 cage number, Haenam province has shown 131 cage number. The lower production abalone price of recent means higher BEP level.

On the Optimization Methods of Spatial Proximity to Set the Class Intervals for the Choropleth Map (단계구분도의 계급구간 설정을 위한 공간적 인접성의 최적화기법에 관해)

  • Son, Ill
    • Journal of the Korean Geographical Society
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    • 제36권4호
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    • pp.434-443
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    • 2001
  • Differing from the existing method to optimize the statistical proximity, the new optimization method was developed to maximize the spatial proximity among the unit areas of choropleth map. 25 choropleth maps were made using 5 classification methods(maximum BEI, maximum TEI, equal interval, natural break, n-tile) for 5 classes(3∼7) and were analyzed to elucidate the effectiveness of classification methods on the basis of 3 evaluation indeces (TEI, BEI, $C_{F}$). The results from the maximum TEI and maximum BEI were evaluated as relatively stable and effective compared to those from other classification methods. But they showed the opposite trends owing to the trade-off relationships. Meanwhile, the resets from the natural break method got higher marks, which was also identified through the analysis using a new $alpha$-index.x.

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