• 한국인쇄학회지
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• 제18권1호
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• pp.103-112
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• 2000

The color space transformation to link device-dependent color spaces and device-independent color spaces is essential for device characterization and cross-media color reproduction. There are various color conversion methods such as regression, 3D interpolation with LUT(look-up table), and neural network. In the color transformation with these methods, the conversion accuracy is essentially based on the sample data to be exploited for device characterization. In conventional method, color samples are uniformly selected in device-dependent space such as CMY and RGB. However, distribution of these color samples is very non-uniform in device-independent color space such as CIEL*a*b*. Accordingly, the conversion error in device-independent color space is irregular according to the distribution of the samples. In this paper, a color sampling method based on equi-visual perception is proposed to obtain approximate uniform color samples in CIEL*a*b* space. In order to evaluate transformation accuracy of proposed method, color space transformations are simulated using regression, 3D interpolation with LUT and neural network techniques, respectively.

• Journal of Korean Society for Atmospheric Environment
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• 제21권E3호
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• pp.107-113
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• 2005

Using a sampling device of our own making, airborne pollen has been monitored in Kyoto, Japan from the middle of February to the end of May 2004. From the morphological analysis of pollen grains by Scanning Electron Microscope (SEM), it was possible to identify some pollen types like Cryptomeria, Pine, Alder, Cyclobalanopsis, Chamaecyparis, and Equisetum. Daily average airborne pollen counts show strong variations from the day to day which makes the appropriate daily forecasts that could be of practical use for patients difficult. Diurnal variation of airborne pollen grains at our local sampling site is very irregular and shows no similarity between pollen types. The highest concentrations of Cryptomeria and Alder pollens in the south -west wind directions might be attributed to the airborne pollen transport, while the increase in Pine pollen grain in the southern wind direction was probably due to the local spread. Prevailing wind direction (SW) during the pollinating periods of Cryptomeria and Alder pollens could suggest a long-distance transport from a distant mountain.

• Fibers and Polymers
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• 제6권1호
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• pp.66-71
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• 2005

The surface evenness and texture are closely related with the irregularity of yam thickness. Besides, yam thickness variation has an important role to influence the yam performance and the textile process efficiency. Thus, the information not only on the yam thickness, but also on the short- term irregular characteristics that have not been known before is required for enhancing the qualities of textile products. This paper reports the results of a study about the yam thickness and its variation for various types of yam on the basis of a new measurement system applying a laser slit beam as a light source. The new method delivers effective information on the irregularity. The analysis of the measured signal confirms that the visual shade created by the yam doubling and twisting can be measured and the yam thickness characteristics can be represented by corre­lograms. Depending on yam types, correlograms have different shapes and can be approximated to an exponentially decaying function with or without fluctuating magnitude. In addition, the effective information on the yam irregularity can be influ­enced by the sampling length interval of the measuring device used for tests.

• 천문학회보
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• 제36권2호
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• pp.81.2-81.2
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• 2011

Motivated by recent attempts to derive geomagnetic activity from hourly mean data in long term studies, we test the recursive Kalman filter method to obtain the regular solar variation curve of the geomagnetic field. Using a simple algorithm, we are able to assign a quiet day curve to every day separately, without the need for additional input parameter(s) to define the geomagnetically quiet days. We derive a digital counterpart AhK of the analog range index Ak at the subauroral Sodankyl$\ddot{a}$ station and compare it to the earlier digital estimate Ah and the local Ak index. We find that the new method outperforms the former estimate in every aspect studied and provides a robust, straightforward manner of estimating and verifying the manually scaled Ak index, based on readily available hourly values. The model is independent of sampling; thus, for shorter term studies where high-sampling data are available, more accurate estimates can also be obtained when needed. Therefore, in contrast to other recent approaches, we do not provide a method to quantify irregular activity directly but derive the actual quiet day curves in the traditional manner. In future applications the same algorithm may be used to define a wide variety of geomagnetic indices (such as Ak, Dst, or AE).

• 한국정밀공학회지
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• 제16권12호
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• pp.143-151
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• 1999

The shape of surface micro-crack is very irregular due to nonhomogeneous microstructure but is very important in respect to qualitative estimation of fatigue life. Fractal geomety can quantify the shape of surface mciro-crack. Fractal dimension is measured for surface micro-cracks with coast line and box counting method and estimates cycle ration in Al 2024-T3. The average fractal dimension $D_{favg}$ of surface micro-cracks has 3-parameter weibull distribution and location parameter is nearly constant but shape parameter decreases as cycle ration increases. The fractal dimension by coast line method is measured for individual surface micro-crack but the fractal dimension by box countin method is measured for all the surface micro-cracks under sampling area. Therefore, This paper shows fractal dimension $D_{fb}$ can predict cycle ratio $N/N_f$ more convenient than fractal dimension $D_{favg}$.

• 천문학회보
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• 제39권2호
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• pp.101.1-101.1
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• 2014

The fluctuation of VLBI visibility phase can be occurred, predominantly caused by the irregular distribution and motion of water vapor in the atmosphere at high frequencies (>1GHz). This radio-seeing effect shows up on filled-aperture telescopes as an anomalous refraction (AR). This can be shown as if the antenna pointing-offset increases, in other words the apparent displacement of radio sources from its nominal position happens. We carried out the single-dish observations on KVN sites in order to check the effect of AR from 2010 to 2014. Orion KL, U Her, and R Leo were observed with 1second sampling time at 22.235GHz and 43.122GHz simultaneously. Each source was observed with the tracking mode for 30 minutes per a source. We analyzed the structure function, power spectrum and Allan variance of the data according to a day and a night, a season and observatories. Finally, we can infer that the AR effect depends on the atmospheric environment, especially tropospheric turbulence.

• 한국학교ㆍ지역보건교육학회지
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• 제11권2호
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• pp.71-87
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• 2010

Objectives: The purpose of this study was to find out the prevalence of constipation, related factors of constipation of female high school students. Methods: The study subjects were 322 students of Y high schools located in a Suwon city, who were selected by the accidental sampling from November 2009. We analyzed the data by frequency analysis, Chi-square test, Logistic regression analysis using SPSS ver.12.0. Results: The results of this study were summarized as follows: A prevalence rate of self-reported constipation was 55.3%. From the Logistic analysis by self-reported method, leading causes of constipation on the students were drinking beverage, the less frequency of having meals, irregular time of having meals, not eating breakfast, insufficient exercise and not evacuating the bowels regularly. Conclusions: Based on these results, intervention to increase the amount of beverage constipation, intake of vegetable, regularity of taking meals, stress management should be provided to prevent the constipation.

• 대한원격탐사학회지
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• 제26권6호
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• pp.721-730
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• 2010

In satellite remote sensing, irregular temporal sampling is a common feature of geophysical and biological process on the earth's surface. Lee (2008) proposed a feed-back system using a harmonic model of single period to adaptively reconstruct observation image series contaminated by noises resulted from mechanical problems or environmental conditions. However, the simple sinusoidal model of single period may not be appropriate for temporal physical processes of land surface. A complex model of multiple periods would be more proper to represent inter-annual and inner-annual variations of surface parameters. This study extended to use a multi-periodic harmonic model, which is expressed as the sum of a series of sine waves, for the adaptive system. For the system assessment, simulation data were generated from a model of negative errors, based on the fact that the observation is mainly suppressed by bad weather. The experimental results of this simulation study show the potentiality of the proposed system for real-time monitoring on the image series observed by imperfect sensing technology from the environment which are frequently influenced by bad weather.

• 한국보건간호학회지
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• 제3권1호
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• pp.5-17
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• 1989

The purpose of this study was to investigate the natural menopause age of middle-aged women in Korea and to analyse various factors affecting them. For the collection of date, 1,140 women aged between 45-54 were selected through stratified sampling technics in Seoul and at a rual area in Kyong KiProvince. They were interviewed from Nov. 1 through Dec. 31,1987 by use of questionnaires made after pilot study had been performed twice. Among them the final subjects for analysis were restricted to only those who had experienced menopause or irregular menstruation during the past one year, the number of which was total 410:206 in urban and 204 in rural area. For the analysis, menopause age was used as dependent variables while fertility variables, socio-economic variables, bio-physical varibles, and insight of life variables were classified as independent variables. Dependent variables such as menopause was tested and analysed by descriptive statistical methods(e.g., frequency, percentage, mean, $X^2-test.$ t-test, ANOVA). The relation between menopause age and independent variables was analysed by use of Pearson's correlation coefficients. For the analysis of various factors affecting menopause age, multiple stepwise regression method was used. The obtained results are summarized as follows: 1. The natural menopause age of Korean women were 47.2 mean age: it was 47.7 and 46.7 mean age in urban and rural area respectively, which revealed that the former was later then the latter by one year. And the recollective error on menopause starting age between the menopause group and the group who had experienced irregular menstruation during the past one year was 0.4-0.7 year. 2. The main factors affecting the menopause age were (1) the duration of marital life, (2) the duration of oral pill use, (3) insight of life and economic status, (4) educational background. (5) menarche, (6) usual menstruation amount, (7) electic charge. and (8) area. These factors. altogether, could explain $18.4\%$ of factors related with menopause, and they took the high percentage in the order mentioned.

• 한국식품위생안전성학회지
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• 제15권3호
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• pp.199-203
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• 2000

대장균의 지다당류가 호르몬에 미치는 영향을 조사하기 위해 토끼를 대상으로 실험을 하였다. 지다당류 투여 그룹의 콜티졸, 에피네프린, 노어에피네프린 농도는 전체 측정시기에 걸쳐(3시간에서 72시간) 대조군보다 유의하게 높았고(p<0.05혹은 p<0.01) 이 호르몬들 각각의 최고치는 24시간, 3시간, 12시간대였다. 인슐린 및 글루카곤 농도는 지다당류투여후 12시간까지 대조군보다 높았으며 (p<0.05 혹은 p<0.01) 그 최고치는 각각 12시간과 6시간대였으며, 이후 24시간에서 72시간까지는 대조치보다 약간 낮았다. 콜티졸 농도의 변화는 용량의존적이었으나 나머지 호르몬의 변화양상은 불규칙하였다. 본 연구의 결과들은 대장균지다당류가 콜티졸, 에피네프린, 노어에피네프린과 같은 스트레스성 호르몬의 분비와 내분비계의 혼란을 유도한다는 점을 보여주고 있다. 이러한 지다당류로 인한 호르몬계의 혼란은 생리학적으로 치명적 결과를 초래할 수도 있다.