• 제목/요약/키워드: low sample size

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시장, 기업규모, 기술수준에 따른 M/B비율과 부채비율 간의 관계 검정 : 한국 유가증권시장 및 코스닥시장 상장기업을 중심으로 (The Test of Relation between M/B Ratio and Debt Ratio by Market, Firm Size, and Technology Level)

  • 김진수;권기정
    • 국제지역연구
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    • 제13권3호
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    • pp.527-549
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    • 2009
  • 본 연구는 Chen and Zhao(2006)에 의해 실증된 M/B비율과 부채비율 간의 역 U자형 관계가 시장, 기업규모 및 기술수준별로 어떠한 차이를 보이는지를 검정하여 보았다. 이를 위해 2001년도 1월 1일부터 2008년도 12월 31일까지 한국 유가증권시장과 코스닥시장에 계속 상장된 510개 기업, 4,080개의 관측수를 확보하였다. 각 표본별 관측수는 유가증권시장표본이 2,448개이며, 코스닥시장표본이 1,632개이다. 기업규모별로는 대기업표본이 1,816개, 중소기업표본이 2,264개이며, 기술수준별로는 중 및 저기술업종표본이 1,704개, 첨단 및 고기술업종표본이 2,376개이다. 주요 실증분석결과는 다음과 같다. 첫째, 평균 M/B비율은 유가증권시장표본(대기업표본, 중 및 저기술업종표본)에 비해 코스닥시장표본(중소기업표본, 첨단 및 고기술업종표본)이 높았으며, 유상증자비율의 평균 역시 전자에 비해 후자가 높았다. 둘째, 코스닥시장표본(중소기업표본, 첨단 및 고기술업종표본)의 경우 M/B비율과 부채비율 간에 역 U자형 관계를 확인할 수 있었으나, 유가증권시장표본(대기업표본, 중 및 저기술업종표본)의 경우 이러한 관계를 찾아볼 수 없었다. 후자에 있어 역 U자형 관계가 나타나지 않는 것은 이들 기업의 낮은 M/B비율에 기인한 것으로 생각된다.

사이즈 적합성과 효율성이 향상된 야구 다리보호대 개발을 위한 그레이딩 편차 선정 (Selection of Grading Deviations to Develop Improved Baseball Leg Guards for Size Suitability and Efficiency)

  • 이효정;엄란이;이예진
    • 한국의류학회지
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    • 제41권1호
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    • pp.184-195
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    • 2017
  • Baseball is a life sport that gives vitality to people. However, currently available leg guards do not have a variety of sizes and it is very difficult to purchase a leg guard that is suitable for the size of a specific consumer. Therefore, this study investigated the size system of a leg guard sold in the market and suggested a grading deviation suitable for the legs of Korean males. The results of the study were as follows. First, most brands were sold only in three size systems as children's, teenagers, and adults. Adult size systems were not subdivided. Second, Korean male legs were classified into Group 1 (large girth and height and lower body muscle) and Group 2 (small girth and height and low underbody muscle). Third, the size system is based on vertical items such as height and mid-thigh circumference. Each group produced 10 sizes. The smallest height or the largest height was also found to be about 4.5 to 5.0cm smaller or larger than the sample size for each group. The total length of the leg guard was about 2.5cm when the height was increased or decreased by one size. It was confirmed that the deviation of the circumference of the mid-thigh should be about 2.0cm larger or smaller than the sample size even if the height is the same. The deviation of the knee circumference and ankle circumference was smaller than the other circumference. In conclusion, the dimension combinations of the leg guard must be set differently to provide a leg guard with high size suitability according to leg type.

Generative Adversarial Networks for single image with high quality image

  • Zhao, Liquan;Zhang, Yupeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권12호
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    • pp.4326-4344
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    • 2021
  • The SinGAN is one of generative adversarial networks that can be trained on a single nature image. It has poor ability to learn more global features from nature image, and losses much local detail information when it generates arbitrary size image sample. To solve the problem, a non-linear function is firstly proposed to control downsampling ratio that is ratio between the size of current image and the size of next downsampled image, to increase the ratio with increase of the number of downsampling. This makes the low-resolution images obtained by downsampling have higher proportion in all downsampled images. The low-resolution images usually contain much global information. Therefore, it can help the model to learn more global feature information from downsampled images. Secondly, the attention mechanism is introduced to the generative network to increase the weight of effective image information. This can make the network learn more local details. Besides, in order to make the output image more natural, the TVLoss function is introduced to the loss function of SinGAN, to reduce the difference between adjacent pixels and smear phenomenon for the output image. A large number of experimental results show that our proposed model has better performance than other methods in generating random samples with fixed size and arbitrary size, image harmonization and editing.

대구 패션 소비자의 구매성향 분석 - 동성로 야시골목을 중심으로 - (An Analysis on Shopping Orientations of Small Store User in Yhasi street of Dong-Sung Ro, Daegu)

  • 김정원
    • 한국의류산업학회지
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    • 제3권1호
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    • pp.61-69
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    • 2001
  • The purpose of this study was to analyze the purchasing behavior related factors of Small Store User in Yhasi street of Dong-Sung Ro, Daegu. Frequency, $X^2$-test MANOVA, ANOVA and Duncan multiple range test were used to analyze the sample. The results of this study were as follows: 1) The largest sample were as follows: un married female, college students of twenties, 101-200 thousand won for salaries. 2) The factors of purchasing behavior were classified into 8 factors, enjoy shopping, store image, unique goods, culture space, salesperson, low price, information seeking, value via price orientation. 3) There were significant differences found between attitude on information source, number of seeking store, music in shop, music sound, size, display, price, street, in their factors of purchasing behavior (unique goods, value via price, low price, store image, enjoy shopping) 4) There were significant differences found between demographic characteristics (personal sales, location, transportation) in their factors of purchasing behavior (salesperson, cultural space, store image).

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Chamotte질 내화물의 강도에 미치는 유이 Silica의 영향 (The Effect of Free Silica on the Strength of Chamotte Refractory)

  • 박금철;최영섭
    • 한국세라믹학회지
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    • 제13권1호
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    • pp.35-44
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    • 1976
  • The effect of quartz which exists in clays, especially in kaolin used for the production of chamotte sagger, on the strength of refractory was examined. In this study, a mixture of chamotte 50%, kaolin 25%, plastic clay 25% in ternary component system was selected as a batch composition. To this mixture 1%, 3% and 5% of feldspar and sericite were added respectively. The plastic clay used here was separated under 170 mesh by dry process. Feldspar and sericite were separated under 325 mesh by dry process. Feldspar and sericite were separated under 325 mesh by dry process. In order to change the particle size and the content of quartz, the kaolin was separated under 60, 115, 170 and 325 mesh by wet process, substituted quartz for coarse parts of it. Chamotte was classified into three grades, coarse (5-10mesh): medium (10-20mesh): fine(20-115mesh) and the ratio was 1:1:1. Samples were formed in 0.8xIx10cm size with 12.5% water at 160kg/$\textrm{cm}^2$ pressure, and fired at 130$0^{\circ}C$ for 1 hr. The fired samples were ivnestigated by means of x-ray diffraction analysis and microscopic observation, and the physical properties of them were also examined, such as firing shrinkage, apparent specific gravity and bulk specific gravity, apparent porosity, water absorption and modulus of rupture. The obtained results are as follows: 1. When screened kaolin with low content of quartz was added to fixed chamotte-plastic clay system, the sample lowered modulus of rupture and increased apparent porosity as the size of kaolin became finer. 2. When kaolin under 325 mesh with 7.2-15.81% quartz between 60-325 mesh was added to fixed chamotte-plastic clay system, the sample had higher apparent porosity and lower modulus of ruputure as the size and the amount of quartz became larger. 3. The addition of feldspar and sericite to chamotte-plastic clay system improved apparent porosity and modulus of rupture. The effect of feldspar was better when quartz content was low, although that of sericite was better than quartz content was high.

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저소득층 취업모 아동의 방과후 생활조사 (The Survey on the Low Income Children's After-School Care)

  • 정현희
    • 대한가정학회지
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    • 제34권2호
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    • pp.379-390
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    • 1996
  • This study attempted to investigate the state of the children's after-school care with low income employed mothers. The survey was conducted by means of the structured questionnaire. The questionnaire was built on the previous studies. The sample size was 418 mothers in Pusan. The results were summarized as follows : 1. Most of the children with low class employed mothers showed the self-care state. 2. Most of the children with low class employed mothers were found to spend more time alone in their houses. 3. Most of the children with low class employed mothers tended to have more difficulties in getting contact with their mothers and they were left to prepare their foods by themselves. 4. Most of the low class employed mother thought that safer environment and better education were immediate problems to be solved for their children's. 5. Most of the low class employed mothers needed after-school care facilities.

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Bayesian MCMC를 이용한 저수량 점 빈도분석: II. 적용과 비교분석 (At-site Low Flow Frequency Analysis Using Bayesian MCMC: II. Application and Comparative Studies)

  • 김상욱;이길성
    • 한국수자원학회논문집
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    • 제41권1호
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    • pp.49-63
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    • 2008
  • 본 연구에서는 Bayesian MCMC 방법과 2차 근사식을 이용한 최우추정(Maximum Likelihood Estimation, MLE)방법 방법을 이용하여 낙동강 유역의 본류지점인 낙동, 왜관, 고령교, 진동지점에 대한 점 빈도분석을 수행하고 그 결과로써 불확실성을 포함한 빈도곡선을 작성하였다. 통계적 실험을 통한 두 가지 추정방법의 분석을 위하여 먼저 자료의 길이가 100인 8개의 합성 유량자료 셋을 생성하여 비교 연구를 수행하였으며, 이를 자료길이 36인 실측 유량 자료의 추정결과와 비교하였다. Bayesian MCMC 방법에 의한 평균값과 2차 근사식을 이용한 취우추정방법에 의한 모드에서의 2모수 Weibull 분포의 모수 추정값은 비슷한 결과를 보였으나, 불확실성을 나타내는 하한값과 상한값의 차이는 Bayesian MCMC 방법이 2차 근사식을 이용한 취우추정방법보다 불확실성을 감소시켜 나타내는 것을 알 수 있었다. 또한 실측 유량자료를 이용한 결과, 2차 근사식을 이용한 취우추정방법의 경우 자료의 길이가 감소됨에 따라 불확실성의 범위가 합성유량자료를 사용한 경우에 비해 상대적으로 증가되지만, Bayesian MCMC 방법의 경우에는 자료의 길이에 대한 영향이 거의 없다는 결론을 얻을 수 있었다. 그러므로 저수량 빈도분석을 수행하기 위해 충분한 자료를 확보할 수 없는 국내의 상황을 감안할 때, 위와 같은 결론으로부터 Bayesian MCMC 방법이 불확실성을 표현하는데 있어서 2차 근사식을 이용한 최우추정방법에 비해 합리적일 수 있다는 결론을 얻을 수 있었다.

GPS 항재밍을 위한 적응 배열 안테나의 성능 분석 (Performance Analysis of Adaptive Array Antenna for GPS Anti-Jamming)

  • 정태희
    • 한국군사과학기술학회지
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    • 제16권3호
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    • pp.382-389
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    • 2013
  • In anti-jamming GPS receiver, adaptive signal processing techniques in which the radiation pattern of adaptive array antenna of elements may be adaptively changed used to reject interference, clutter, and jamming signals. In this paper, I describes adaptive signal processing technique using the sample matrix inversion(SMI) algorithm. This adaptive signal processing technique can be applied effectively to wideband/narrowband anti-jamming GPS receiver because it does not consider the satellite signal directions and GPS signal power level exists below the thermal noise. I also analyzed the effects of covariance matrix sample size and diagonal loading technique on the system performance of five-element circular array antenna. To attain near optimum performance, more samples required for calculation covariance matrix. Diagonal loading technique reduces the system nulling capability against low-power jamming signals, but this technique improves robustness of adaptive array antenna.

A Note on the Small-Sample Calibration

  • So, Beong-Soo
    • 품질경영학회지
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    • 제22권2호
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    • pp.89-97
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    • 1994
  • We consider the linear calibration model: $y_1={\alpha}+{\beta}x_i+{\sigma}{\varepsilon}_i$, i = 1, ${\cdots}$, n, $y={\alpha}+{\beta}x+{\sigma}{\varepsilon}$ where ($y_1$, ${\cdots}$, $y_n$, y) stands for an observation vector, {$x_i$} fixed design vector, (${\alpha}$, ${\beta}$) vector of regression parameters, x unknown true value of interest and {${\varepsilon}_i$}, ${\varepsilon}$ are mutually uncorrelated measurement errors with zero mean and unit variance but otherwise unknown distributions. On the basis of simple small-sample low-noise approximation, we introduce a new method of comparing the mean squared errors of the various competing estimators of the true value x for finite sample size n. Then we show that a class of estimators including the classical and the inverse estimators are consistent and first-order efficient within the class of all regular consistent estimators irrespective of type of measurement errors.

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바이오용 마이크로 핀의 제작에 관한 연구 (A study on Manufacturing of Micro Dotting Pin)

  • 이영수;김광순;김병희
    • 산업기술연구
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    • 제23권A호
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    • pp.21-27
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    • 2003
  • The bio-micro pin is usually used for biochemistry analysis. The capability of manufacturing the micro-pin and array with effective and low-cost way is very important to developers. The micro-pin is composed of "sample channel" putting liquid into already fixed volume, "flat tip" having connection with printing quantity, and "head part" for preventing it from rotation of pin in the holder. We analyzed out printing variation in accordance with shape and tip size of the micro-pin point channel, In this study, we suggested the manufacturing progress and shape demand condition of the micro-pin which could put $0.2{\mu}{\ell}$-biochemistry material into the sample volume, and will be able to produce the micro-pin which can put $10n{\ell}$-biochemistry material into the sample volume in the future.

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