• 제목/요약/키워드: Objective Indicator

검색결과 450건 처리시간 0.028초

레이더 자료를 이용한 강우입자분포의 통계적 분석 연구 (Rain Cell Size Distribution Using Radar Data During Squall Line Episodes)

  • Ricardo S. Tenorio;Kwon, Byung-Hyuk;Lee, Dong-In
    • 한국정보통신학회논문지
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    • 제4권5호
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    • pp.971-976
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    • 2000
  • The main objective of this paper is to present the rain cell size distribution observed during squall line episodes in the Sudano-Sahelian region. The used data were collected during the EPSAT Program [Etude des Precipitation par SATellite (Satellites Study of Precipitation)] which has been developed since 1958, on an experimental area located near Niamey, Niger (2 10′32"E, 13 28′38"N). The data were obtained with a C-band radar and a network composed of approximately 100 raingages over a 10,000 $\textrm{km}^2$. In this work a culling of the squall line episodes was made for the 1992 rainy season. After radar data calibration using the raingage network a number of PPI (Plan Position Indicator) images were generated. Each image was then treated in order to obtain a series of radar reflectivity (Z) maps. To describe the cell distribution, a contouring program was used to analyze the areas with rain rate greater than or equal to the contour threshold (R$\geq$$\tau$). 24700 contours were generated, where each iso-pleth belongs to a predefined threshold. Computing each cell surface and relating its area to an equi-circle (a circle having the same area as the cell), a statistical analysis was made. The results show that the number of rain cells having a given size is an inverse exponential function of the equivalent radius. The average and median equivalent radii ate 1.4 and 0.69 In respectively. Implications of these results for the precipitation estimation using threshold methods are discussed.

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평지붕 건물 축소모형의 지붕색에 대한 표면 온도의 비교평가: 쿨루프 성능평가 차원에서 (Comparative Evaluation of Surface Temperature among Rooftop Colors of Flat Roof Building Models : Towards Performance Evaluation of Cool Roof)

  • 류택형;엄정섭
    • KIEAE Journal
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    • 제13권6호
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    • pp.83-91
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    • 2013
  • Cool roofs are currently being emerged as one of important mechanism to save energy in relation to the building. It is specifically proposed that the changing trends of rooftop surface temperature in the flat roof building model could be used effectively as an indicator to reduced cooling load reduced by cool roof since it can present stable temperature record, that is not influenced according to the nearby physical as well as human variables. The temperature of cool roof in summer was lower around $20^{\circ}C$, compared to the general roofs. Such a seasonal or daily comparative study for rooftop temperature in the building model will highlight that the cool roof efficiency could be calculated in much area-wide context according to rooftop color distribution in urban residential area. It is anticipated that this research output could be used as a valuable reference in identifying energy saving by cool roof since an objective monitoring has been proposed based on the rooftop temperature in the building model, fully quantitative performance of thermal infrared image.

특발성안면신경마비환자의 양도락 변화에 대한 임상적 고찰 (The Clinical Study on Yangdorak Change with Idiopathic Facial Paralysis Patients)

  • 김경옥;양재철;문경숙;이경윤;장조웅
    • Journal of Acupuncture Research
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    • 제22권6호
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    • pp.201-209
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    • 2005
  • Objectives : We investicated correlation between Yangdorak and Meridian at Idiopathic facial nerve paralysis patients. Methods : For Yangdorak examination, We made a comparison between 21 patients who were diagnosticated to Idiopathic facial nerve paralysis and 22 persons who were not. Results : 1. The stress showed the highest frequency in premonitory cause at onset. 2. In comparing results on the Yangdorak general mean, they were not statistically significant between two group(p<0.05). 3. In comparing results on the Stomach(ST)-meridian Yangdorak mean, Idiopathic facial nerve paralysis group is stastically significant in comparison with non-facial paralysis group(p<0.05). 4. In comparing results on the Small Intestine(SI)-meridian Yangdorak mean, Idiopathic facial nerve paralysis group is not stastically significant in comparison with non-facial paralysis group(p<0.05). Conclusion : Yangdorak may be used for a method to objective clinical examination. But further studies are required for a use of practical indicator.

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빔 구조물의 모달 변형에너지를 이용한 손상탐지 (Damage Detection in a Beam Structure Using Modal Strain Energy)

  • 박수용;최상현
    • 한국전산구조공학회논문집
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    • 제16권3호
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    • pp.333-342
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    • 2003
  • 본 논문의 목적은 빔 구조물에서 발생할 수 있는 손상의 위치를 탐색하고, 그 손상의 정도를 추정할 수 있는 알고리즘을 제안하는 것이다. 제안된 방법은 구조물의 모달 변형에너지의 차이를 이용한다. 구조물 내 발생한 국부적인 손상의 위치를 파악하고 그에 상응하는 손상도를 추정할 수 있는 손상지수를 손상 전과 손상 후 구조물의 모드형상에서 얻을 수 있는 모달 변위로 표현하였고 그 관계식을 정립하였다. 구조물 내 손상의 위치를 결정하는 방법은 기 개발된 손상 지표를 적용하였다. 제안된 방법의 우수성과 효용성은 수치적으로 손상을 모사한 빔 구조물을 이용하여 입증하였다.

가족 생활주기에 따른 가족외식 구매결정 과정에서 가족 구성원의 영향력과 외식선택 속성에 관한 연구 -패밀리 레스토랑을 중심으로- (A Study on the Family Decision Making and Choice Behavior of Family Dining out From a Family Life Cycle Perspective : Family Restaurant Study)

  • 채신석;이은수;최승만
    • 한국관광식음료학회지:관광식음료경영연구
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    • 제17권1호
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    • pp.1-20
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    • 2006
  • The family life cycle is a useful indicator of consumer behavior, as well as the family life cycle concept utilizes a combination of demographic and socioeconomic variables that best explains the changes in the construct of the family. The family decision-making research has frequently examined role relationship between husband and wife across stages and sub-decisions. The objective of this research is to measure children and parents' perceptions of the influence of the decision-making process for a family dining-out experience, and to determined the customers' choice behavior of restaurants according to isolated factors underlying the important attributes of the restaurants, and finally authors applied a market segmentation approach by capturing customers' preference of restaurant attributes in family dining-out situation and to investigated influence of the family decision making for family dining out in family life cycle. For practitioner, marketing implications are provided and recommendations for future research are also discussed.

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남한강 수계에서 장기 이화학적 수질특성에 대한 토지이용도 및 계절성 강우의 영향 (Influence of Landuse Pattern and Seasonal Precipitation on the Long-term Physico-chemical Water Quality in Namhan River Watershed)

  • 이지은;최지웅;안광국
    • 한국환경과학회지
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    • 제21권9호
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    • pp.1115-1129
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    • 2012
  • The objective of this study was to analyze long-term annual and seasonal trends of water chemistry on landuse patterns and seasonal precipitation using 72 sampling sites within Namhan River watershed during 2001-2010. Water quality, based on multi-parameters of water temperature(WT), dissolved oxygen(DO), biochemical oxygen demand(BOD), chemical oxygen demand(COD), suspended solids(SS), total nitrogen(TN), total phosphorus(TP), and electric conductivity(EC) varied largely depending on monsoon rain and landuse patterns such as forest, cropland, and residence. Concentrations of BOD and COD as an indicator for organic matter pollution, increased during summer monsoon season at the cropland and residential streams. Values of TN and TP were higher in residential streams than in the forest and cropland streams. In the meantime, DO values had weak relations to the landuse patterns of forest and cropland cover. Water quality was worst in cropland and residential streams, and also most degradated in 4th order streams. Overall, our results suggest that efficient water quality management is required in the cropland and residential landuse streams.

System-Level Performance of Limited Feedback Schemes for Massive MIMO

  • Choi, Yongin;Lee, Jaewon;Rim, Minjoong;Kang, Chung Gu;Nam, Junyoung;Ko, Young-Jo
    • ETRI Journal
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    • 제38권2호
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    • pp.280-290
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    • 2016
  • To implement high-order multiuser multiple input and multiple output (MU-MIMO) for massive MIMO systems, there must be a feedback scheme that can warrant its performance with a limited signaling overhead. The interference-to-noise ratio can be a basis for a novel form of Codebook (CB)-based MU-MIMO feedback scheme. The objective of this paper is to verify such a scheme's performance under a practical system configuration with a 3D channel model in various radio environments. We evaluate the performance of various CB-based feedback schemes with different types of overhead reduction approaches, providing an experimental ground with which to optimize a CB-based MU-MIMO feedback scheme while identifying the design constraints for a massive MIMO system.

편측 성대마비와 성대폴립 환자의 수술 전후 음성검사와 이미지 화상분석의 상관관계에 대한 객관적 비교연구 (Comparative Study of Pre and Postoperative Voice and Image Analysis in Unilateral Vocal Cord Paralysis and Vocal Polyp)

  • 김시찬;정유삼;홍정표;오정석;최홍식
    • 대한후두음성언어의학회지
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    • 제11권1호
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    • pp.20-27
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    • 2000
  • To determine what is the change of pre and postoperative voice and image analysis parameters and correlations between them, videostroboscopy was analyzed in each 18 patients with unilateral vocal cord paralyses or vocal polyps before and after the surgery from November, 1996 to April, 1999. The correlation between acoustic and aerodynamic parameters was investigated. The software-Videolink and $\pi$-View(Mediface Co, Seoul, Korea)-was used in a quantitative analysis. In unilateral vocal cord paralysis, the glottic angle is well correlated with maximum phonation time, jitter and shimmer preoperatively. The postoperative glottic angle is also correlated with preoperative maximum phonation time. In patients with the vocal polyp, the chink is postoperatively decreased, but the size of the chink and the polyp is not correlated with pre and postoperative voice analysis parameters. These findings reveal that glottic an and vocal fold angle are good indicators of e postoperative glottic configuration in unilateral vocal cord paralysis. Vocal fold ratio is also a useful indicator that represents the length of vocal folds. We consider that the computerized analysis through videostroboscopy is one of objective diagnostic methods in many voice disorders if we can measure a distance between the telelaryngoscope and vocal folds.

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Hypoxia-inducible Factor 1 Alpha (HIF-1α) as a Prognostic Indicator in Patients with Gastric Tumors: A Meta-analysis

  • Zhang, Zhi-Gang;Zhang, Qiu-Ning;Wang, Xiao-Hu;Tian, Jin-Hui
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권7호
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    • pp.4195-4198
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    • 2013
  • Background and Objective: Though researched for years, the prognostic role of hypoxia-inducible factor 1 alpha (HIF-$1{\alpha}$) in gastric cancer is still controversial. We thus undertook a systematic review to assess the relationship. Method: A systematically literature search of Pubmed, Embase, Web of Science, China Biological Medicine Disc and Cochrane Library was undertaken in February 2013, and the reference lists of articles were retrieved. Results: 12 trials (1,555 participants) were included to assess the association between HIF-$1{\alpha}$ expression and survival. Summary hazard ratios (HRs) were calculated. HIF-$1{\alpha}$ expression was significantly correlated with poor overall survival of gastric cancer patients (HR=1.34, 95%CI: 1.13-1.58; P=0.0009), but not with poor disease free survival of gastric cancer patients (HR=1.67, 95%CI: 0.99-2.82; P=0.06). Conclusion: HIF-$1{\alpha}$ was associated with poor OS, but not DFS, especially for Asian patients. But studies evaluating relationships of HIF-$1{\alpha}$ with OS and DFS in non-Asian gastric cancer patients appear needed.

정보시스템 이용자의 정보만족도 측정에 관한 이론적 고찰 (A Theoretical Study on the Measurement of User Information Satisfaction on the Information System)

  • 안상근;최민호;김성수
    • 농촌지도와개발
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    • 제4권1호
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    • pp.201-209
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    • 1997
  • The objective of this study were 1) to review concepts of user information satisfaction (UIS), 2) to analyze tools for measuring user information satisfaction, 3) to identify factors affecting information satisfaction. The study was carried out by the analysis of literatures related to information system. The construct of UIS has been operationalized in many different ways. Several studies employed single-item rating scales; such scales have been criticized as unreliable. Single-item scales also provide little information as to what the user finds dissatisfying(satisfying) and are thus of limited utility outside a research setting. Multiple-item UIS measures have become increasingly common. Generally, they are of two types. The first focuses on the information system product. With such diverse names as "system acceptance", "output quality", and "appreciation", these scales focus on the content of the information system and the manner in which the information is presented. The second type of multiple-item scale includes the organizational support for developing and maintaining the system as well as the system product itself. This type of instrument contains items concerned with training, documentation, development procedures, systems maintenance, etc., as well as items related to system content. Thus it provides an indicator of the overall quality of information services provided by an information service function. Generally, UIS measures have not been carefully validated. Recently, however, several rigorous attempts have been made to develop valid and reliable UIS measure.

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