• 제목/요약/키워드: Missing cell

검색결과 53건 처리시간 0.023초

A Study on the Influence of a Missing Cell in a Class of Central Composite Designs

  • Park, Sung-Hyun;Noh, Hyun-Gon
    • Journal of the Korean Statistical Society
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    • 제27권1호
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    • pp.133-152
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    • 1998
  • The central composite design is widely used in the response surface analysis, because it can fit the second order model with small experimental points. In practice, the experimental data are not always obtained on all the points. When there are missing observations, many problems due to the missing cells can occur. In this paper, the influence of a missing cell on the central composite design is discussed. First, the influences of a missing cell on the variances of estimated regression coefficents are compared as $\alpha$ varies. Second, how the average predition variance is affected by a missing sell is discussed. And the influence on rotatability is investigated. Third, the influence of a missing cell on optimality, especially on D-optimality and A-optimality, is examined.

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Cell 방식 포장공정에서의 Missing Item 검사 및 관리 시스템 개발 (Development of Missing Item Detection and Management System under Cell Type Packaging Processes)

  • 김현우;최현의;안호균;윤태성
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.344-346
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    • 2009
  • Cell type packaging line is more suitable for the products with various models and small quantities like mobile phone or mp3 player than conveyor type packaging line. Cell type packaging line is applicable to package various product models, but it can cause wrong product compositions and missing of items. So, automatic missing item detection system is needed. We designed an missing item detection system with a bar code reader, infrared sensors, and s digital camera. and also developed the programs for sensor data acquisition, image data processing, GUI, and data management.

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Large tests of independence in incomplete two-way contingency tables using fractional imputation

  • Kang, Shin-Soo;Larsen, Michael D.
    • Journal of the Korean Data and Information Science Society
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    • 제26권4호
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    • pp.971-984
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    • 2015
  • Imputation procedures fill-in missing values, thereby enabling complete data analyses. Fully efficient fractional imputation (FEFI) and multiple imputation (MI) create multiple versions of the missing observations, thereby reflecting uncertainty about their true values. Methods have been described for hypothesis testing with multiple imputation. Fractional imputation assigns weights to the observed data to compensate for missing values. The focus of this article is the development of tests of independence using FEFI for partially classified two-way contingency tables. Wald and deviance tests of independence under FEFI are proposed. Simulations are used to compare type I error rates and Power. The partially observed marginal information is useful for estimating the joint distribution of cell probabilities, but it is not useful for testing association. FEFI compares favorably to other methods in simulations.

OFDMA/TDD 시스템을 위한 효율적인 동기 추정 및 셀 탐색 기법 (An Efficient Synchronization and Cell Searching Method for OFDMA/TDD System)

  • 김정주;노정호;장경희
    • 한국통신학회논문지
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    • 제30권9A호
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    • pp.714-721
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    • 2005
  • 본 논문에서는 직교 주파수 분할 다중 접속/시 분할 다중화(OFDMA/TDD :OFDM-FDMA/ Time Division Duplexing) 시스템에서의 프리앰블 모델을 분석하고, AWGN과 ITU-R M.1225 Ped-B 및 Veh-A 채널 환경에서 OFDMA/TDD 시스템에 적용된 심볼 타이밍 및 반송파 주파수 오프셋 추정과 셀 탐색 성능을 모의 실험을 통하여 그에 따른 성능을 Detection Probability, False Alarm, Missing Probability, Mean Acqusition Time 및 (MSE) Mean Square Error 로 확인한다. 특히, 심볼 타이밍 오프셋 추정에서는 향상된 성능을 가지는 프리앰블 구조 및 알고리즘을 제안한 후, 기존의 프리앰블 구조와 그에 따른 성능을 비교 분석한다.

Expression of a set of glial cell-specific markers in the Drosophila embryonic central nervous system

  • Ahn, Hui Jeong;Jeon, Sang-Hak;Kim, Sang Hee
    • BMB Reports
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    • 제47권6호
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    • pp.354-359
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    • 2014
  • The types of glia in the central nervous system (CNS) of the Drosophila embryo include longitudinal glia (LG), cell body glia (CBG), and peripheral glia (PG). Transcription factors, such as glial cell missing and reverse polarity, are well-established general glial cell markers. Only a few glial cell-specific markers have been identified in the Drosophila embryonic CNS, thus far. In the present study, we employed the glial cell-specific markers for LG (vir-1/CG5453 and CG31235), CBG (fabp/CG6783 and CG11902), and PG (CG2310 and moody/CG4322), and comprehensively analyzed their expression patterns, during the embryonic CNS development. Our study validated the specificity of a set of glial markers, and further revealed their spatio-temporal expression patterns, which will aid in the understanding of the developmental lineage, and investigating their role in the development and homeostasis of the Drosophila CNS in vivo.

휴대폰의 CFA 패턴특성을 이용한 사진 위변조 탐지 (Automatic Detection of Forgery in Cell phone Images using Analysis of CFA Pattern Characteristics in Imaging Sensor)

  • 심재연;김성환
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2010년도 추계학술발표대회
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    • pp.1118-1121
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    • 2010
  • With the advent of cell phone digital cameras, and sophisticated photo editing software, digital images can be easily manipulated and altered. Although good forgeries may leave no visual clues of having been tampered with, they may, nevertheless, alter the underlying statistics of an image. Most digital camera equipped in cell phones employ a single image sensor in conjunction with a color filter array (CFA), and then interpolates the missing color samples to obtain a three channel color image. This interpolation introduces specific correlations which are likely to be destroyed when tampering with an image. We quantify the specific correlations introduced by CFA interpolation, and describe how these correlations, or lack thereof, can be automatically detected in any portion of an image. We show the efficacy of this approach in revealing traces of digital tampering in lossless and lossy compressed color images interpolated with several different CFA algorithms in test cell phones.

A spindle cell squamous cell carcinoma on the cheek presenting with in-transit metastases and a satellite lesion

  • Lee, Eui-Tae
    • 대한두개안면성형외과학회지
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    • 제21권1호
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    • pp.58-63
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    • 2020
  • Spindle cell squamous cell carcinoma (SpSCC) is a biphasic tumor composed of squamous cell epithelial and spindle cell mesenchymal components, both of which are malignant. Cutaneous SpSCC can cause diagnostic and therapeutic difficulties because of its rarity, heterogeneity, morphological similarity to other cutaneous spindle cell neoplasms, and uncertain pathogenesis and prognosis, particularly when the squamous cell carcinoma component is minimal or missing. Intransit metastasis and satellite lesion (satellitosis) constitute a spectrum of non-nodal regional metastases. Here the author reports the first known case of cutaneous SpSCC presenting with intransit metastases and a satellite lesion, which were exceptionally aggressive. A 77-year-old female patient presented with a 3×3×0.5 cm mass on her right cheek. Despite wide excision and postoperative radiation, the patient resulted in local recurrence and multiple distant metastases within 3 months. If many high-risk factors-particularly satellitosis and in-transit metastases are observed in a tumor with epithelial to mesenchymal transition, then further wide excision and adjuvant chemoradiation should be considered early in the treatment process. A multidisciplinary approach could be the key to cure the most aggressive malignancies of the skin, as in other organs.

Plant Cells on Earth and in Space

  • Braun, Markus;Sievers, Andreas
    • Animal cells and systems
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    • 제4권3호
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    • pp.201-214
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    • 2000
  • Two quite different types of plant cells are analysed with regard to transduction of the gravity stimulus: (i) Unicellular rhizoids and protonemata of characean green algae; these are tube-like, tip-growing cells which respond to the direction of gravity. (ii) Columella cells located in the center of the root cap of higher plants; these cells (statocytes) perceive gravity. The two cell types contain heavy particles or organelles (sataoliths) which sediment in the field of gravity, thereby inducing the graviresponse. Both cell types were studied under microgravity conditions ($10^{-4}$/ g) in sounding rockets or spacelabs. From video microscopy of living Chara cells and different experiments with both cell types it was concluded that the position of statoliths depends on the balance of two forces, i.e. the gravitational force and the counteracting force mediated by actin microfilaments. The actomyosin system may be the missing link between the gravity-dependent movement of statoliths and the gravity receptor(s); it may also function as an amplifier.

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홍삼 내백부의 수삼 미세구조 (Ultrastructure of Fresh Root Turned into Inside White of Red Ginseng)

  • 조병구;박훈;이준성
    • Journal of Ginseng Research
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    • 제18권3호
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    • pp.187-190
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    • 1994
  • The pith and xylem parts of fresh root that turned into inside-white during processing for red ginseng was investigated under scanning electron microscope in comparison with the sa31e position of fresh root processed into normal reddening. In the inside-white part starch storage cells remain mostly in vacancy or with small number of starch granules and with large hollow by missing cell membranes between cells. Many starch seed granules appeared on the surface of storage cell wall in the inside-white part. Fresh root sample showed better picture than dried powder.

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A Note on Estimation of Multinomial Probabilities when Some Frequency Counts are Merged

  • Lee, Sang-Eun;Park, C.J.
    • Communications for Statistical Applications and Methods
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    • 제6권1호
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    • pp.327-336
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    • 1999
  • In a multinomial sampling scheme some categories may be observed as partially classified because of technical or economic reasons. In this paper the maximum likelihood estimators(M.L.E) of multinomial probabilities are obtained when some frequencies are merged. We obtained the M.L.E and a method to evaluate the information gained by including merged frequencies in M.L.E we obtained an estimator of the covariance matrix and it is used to examine the information gained by including the merged frequency counts in estimating the cell probabilities. When certain individual frequency counts are missing a method is proposed for estimating the cell probabilities using EM algorithms.

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