• Title/Summary/Keyword: Data Quality Criteria

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A comparative study for reconstructing a high-quality NDVI time series data derived from MODIS surface reflectance (MODIS 지표 분광반사도 자료를 이용한 고품질 NDVI 시계열 자료 생성의 기법 비교 연구)

  • Lee, Jihye;Kang, Sinkyu;Jang, Keunchang;Hong, Suk Young
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.149-160
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    • 2015
  • A comparative study was conducted for alternative consecutive procedures of detection of cloud-contaminated pixels and gap-filling and smoothing of time-series data to produce high-quality gapless satellite vegetation index (i.e. Normalized Difference Vegetation Index, NDVI). Performances of five alternative methods for detecting cloud contaminations were tested with ground-observed cloudiness data. The data gap was filled with a simple linear interpolation and then, it was applied two alternative smoothing methods (i.e. Savitzky-Golay and Wavelet transform). Moderate resolution imaging spectroradiometer (MODIS) data were used in this study. Among the alternative cloud detection methods, a criterion of MODIS Band 3 reflectance over 10% showed best accuracy with an agreement rate of 85%, which was followed by criteria of MODIS Quality assessment (82%) and Band 3 reflectance over 20% (81%), respectively. In smoothing process, the Savitzky-Golay filter was better performed to retain original NDVI patterns than the wavelet transform. This study demonstrated an operational framework of gapdetection, filling, and smoothing to produce high-quality satellite vegetation index.

A Note on the Use of Peer Assessment to Improve Pupil's Performance

  • Lee, Kyung-Koo;Mun, Gil-Seong;Ahn, Jeong-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.2
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    • pp.443-450
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    • 2008
  • Peer assessment is the process of assessment of students by other students and one form of innovative assessment. It actively involves students in the assessment process and is generally agreed that such involvement enhances the quality and effectiveness of the learning process, since assessing something and benchmarking process is a powerful aid to mastering it themselves. It is more effective on the hard courses for them to understand. In this article we present a peer assessment technique which was applied to students enrolled in a mathematical statistics course and a historical course. In order to measure the effectiveness of the technique, students had to evaluate their colleagues based on predefined criteria and a comparison is presented between the instructor assessments and the peer assessment.

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Quality Improvement of B-spline Surfaces through Fairing of Data Points (측정점의 순정을 통한 B-스플라인 곡면 품질의 개선)

  • 흥석용;이현찬
    • Korean Journal of Computational Design and Engineering
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    • v.6 no.1
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    • pp.40-47
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    • 2001
  • In reverse engineering, existing products are digitized fur the computer modeling. Using the digitized data, surfaces are modeled for new products. However, in the digitizing process measuring errors or deviations can be happened often in practice. Thus, it is important to adjust such errors or deviations during the computer modeling. To adjust the errors, fairing of the modeled surfaces is performed. In this paper, we present a surface fairing algorithm based on various fairness metrics. Fairness metrics can be discrete. We adopt discrete metrics for fairing given 3D point set. The fairness metrics include discrete principal curvatures. In this paper, automatic fairing process is proposed for fairing given 3D point sets for surfaces. The process uses various fairness criteria so that it is adequate to adopt designers'intents.

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Evaluation of Shortening the Stay Time of Patients in an Emergency Medical Center (EMC) (응급실 환자의 응급의료센터 체류시간 단축프로그램 개발 및 효과)

  • Kim, Eun-Joo;Lim, Ji-Young
    • Journal of Home Health Care Nursing
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    • v.17 no.1
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    • pp.21-27
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    • 2010
  • Purpose: The study evaluated a program to shorten EMC stay time. Methods: The subjects were EMC patients, and comprised a control group of 8,477 and an experimental group of 8,378. Data were collected from June 2006 to August 2007, and analyzed concerning stay time for doctor visit, decision making, and discharge. The data were analyzed by $X^2$-test and ANCOVA using SPSS14.0. Result: The stay time of doctor visit, decision making and discharge of the experimental group was significantly less compared to the control group. Using second and third grade triage criteria, the stay time of experimental group was statistically reduced from the control. Conclusion: The implemented shortening program was effective in reducing EMC stay time and increasing EMC effectiveness.

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Assessing the Impact of Internal Reference Price on Clothing Purchase Process (의류제품 구매과정에 있어서 내적준거가격의 영향)

  • 이규혜;이은영
    • Journal of the Korean Society of Costume
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    • v.54 no.6
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    • pp.1-12
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    • 2004
  • Price is one of the most important components of marketing mix. For consumers, price is an always-existing cue and definite evaluation criteria. However, information on price is meaningful only when it is perceived. Sources of price perception can be the actual retail price at the selling point, the internal reference price expected by consumers for a certain clothing product, and the external reference price advertised by marketer such as the price before mark-down. The purpose of this study was to investigate the influence of internal reference price on consumers' purchasing process of clothing products. A questionnaire including clothing stimuli was developed in order to assess consumers' internal reference price level. Usable data from 680 adult female urban residents were used for data analysis. Results indicated that consumers with relatively lower internal reference price tend to react low-price focused external reference price and use discount stores and unit price promotions. Consumers with relatively higher internal reference price advertisement are likely to have higher level of education, tend to infer price information to higher quality or prestige of products, and purchase clothing with regular retail price or coupons.

A Critique of Qualitative Research Methodology in Family Studies (가족학 분야에서의 질적 연구 경향 및 방법론적 문제점)

  • 천혜정
    • Journal of Families and Better Life
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    • v.22 no.5
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    • pp.161-173
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    • 2004
  • Although scholars have been using qualitative research commonly since 1990 in Korea, discussions on the criteria for the quality of qualitative research have been rare. The purpose of this paper was to analyze the trends of qualitative research methodology in Family Studies, and critically examine qualitative research articles published in the three most prominent journals in the field of family studies. The three journals were Journal of Korean Home Management Association, Journal of the Korean Home Economics Association, and Journal of Family Relations. During the period from 1998 to 2003, twenty seven published articles were identified as qualitative research articles from the three journals. Qualitative research in family studies had a wide variety of purposes, but the articles shared similar characteristics: the main goal was to understand the nature of the research participants' experiences and perspectives. The common data collection techniques were in-depth interview, journal writing, and document analysis. Also, all research articles had applied various techniques to data analysis such as grounded theory, or van Manen's method. This article also discussed the usefulness of qualitative research methodology in broadening and deepening the knowledge body in Korean Family Studies.

MIL-STD-810 Tailoring for Korean Peninsula and Periphery Climate (한반도 및 주변 권역 기후를 고려한 MIL-STD-810 테일러링에 대한 연구)

  • Kim, Youngrae;Hong, Yeonwoong;Kim, Donggil
    • Journal of Applied Reliability
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    • v.18 no.2
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    • pp.95-103
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    • 2018
  • Purpose: Environment test aim to validate the guarantee of required capability of materiel against various environment conditions which exposed during materiel life-cycle. In this paper, environment test design procedure and tailoring guideline for Korean peninsula and periphery climate are proposed. Methods: To design tailoring guideline, climate data which are regarding Korean peninsula and periphery regions provided from Korea Meteorological Administration (KMA) and National Climatic Data Center (NCDC) are used. Conclusion: For effective environment test, it is important that environment test have to design in considering environment conditions during materiel life-cycle. It is concluded that the high temperature test level can be softer than the test criteria in MIL-HDBK-310, however, the low temperature test level will be expected to be $2{\sim}6^{\circ}C$ harsher than MIL-HDBK-310.

Application Of Information Technologies In Network Mass Communication Media

  • Ulianova, Kateryna;Kovalova, Tetiana;Mostipan, Tetiana;Lysyniuk, Maryna;Parfeniuk, Ihor
    • International Journal of Computer Science & Network Security
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    • v.21 no.12
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    • pp.344-348
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    • 2021
  • The article examines one of the most important means of visualization of mass information on the Internet - information graphics in the broadest sense of the term as a visual technology for presenting mass information. The main objectives of the article are to determine the genre-typological features of infographics and basic technological principles; identification of features of creation and use of information graphics in modern network. Certain benefits of online infographic editors include savings in resources and time. They allow the user, who has basic PC skills, to create standardized infographics based on their own data. In addition, the use of online services develops visual thinking, allows you to get an idea of quality criteria and current trends in infographics, as well as to gain initial experience in the visual presentation of data.

A Model for Performance Analysis of the Information Processing System with Time Constraint (시간제약이 있는 정보처리시스템의 성능분석 모형)

  • Hur, Sun;Joo, Kook-Sun;Jeong, Seok-Yun;Yun, Joo-Deok
    • Journal of Korean Institute of Industrial Engineers
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    • v.36 no.2
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    • pp.138-145
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    • 2010
  • In this paper, we consider the information processing system, which organizes the collected data to meaningful information when the number of data collected from multiple sources reaches to a predetermined number, and performs any action by processing the collected data, or transmits to other devices or systems. We derive an analytical model to calculate the time until it takes to process information after starting to collect data. Therefore, in order to complete the processing data within certain time constraints, we develop some design criteria to control various parameters of the information processing system. Also, we analyze the discrete time model for packet switching networks considering data with no particular arrival nor drop pattern. We analyze the relationship between the number of required packets and average information processing time through numerical examples. By this, we show that the proposed model is able to design the system to be suitable for user's requirements being complementary the quality of information and the information processing time in the system with time constraints.

Development of a decision support system for high quality NC data selection in mold manufacturing (고품질의 사출금형 NC 가공 데이터 선정을 위한 의사결정지원시스템 개발)

  • Heo, Eun-Young;Kim, Bo-Hyun;Kim, Dong-Won;Cho, Min-Ho
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2005.05a
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    • pp.1101-1107
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    • 2005
  • Mold industry has the difficulty to employ young people as the successors of the skilled workers, because it has been regarded as a 3D-jobs(dirty, difficult, and dangerous). To overcome this situation, thus, manufacturing technologies maintained in the factory should be systemized, and engineering systems should support unskilled workers to do their jobs without any difficulty. As a research of developing the supporting system, this study proposes a decision support system that facilitates unskilled workers to easily select high quality NC-data, as well as to increase productivity. The proposed system is assumed to follow a CAM operation scenario that consists of next three steps: 1) identifying several process plans and enumerating feasible unit machining operations (UMOs) from material and part surface information, 2) creating all feasible NC-data based on UMOs using a commercial CAM system, 3) selecting the best NC data among the feasible NC data using four screening criteria, such as machining accuracy, machining allowance, cutting load, and processing time. A case study on the machining of a camera core mold is provided to demonstrate the proposed system.

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