• Title/Summary/Keyword: e-distance 조인 질의

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Closest Pairs and e-distance Join Query Processing Algorithms using a POI-based Materialization Technique in Spatial Network Databases (공간 네트워크 데이터베이스에서 POI 기반 실체화 기법을 이용한 Closest Pairs 및 e-distance 조인 질의처리 알고리즘)

  • Kim, Yong-Ki;Chang, Jae-Woo
    • Journal of Korea Spatial Information System Society
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    • v.9 no.3
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    • pp.67-80
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    • 2007
  • Recently, many studies on query processing algorithms has been done for spatial networks, such as roads and railways, instead of Euclidean spaces, in order to efficiently support LBS(location-based service) and Telematics applications. However, both a closest pairs query and an e-distance join query require a very high cost in query processing because they can be answered by processing a set of POIs, instead of a single POI. Nevertheless, the query processing cost for closest pairs and e-distance join queries is rapidly increased as the number of k (or the length of radius) is increased. Therefore, we propose both a closest pairs query processing algorithm and an e-distance join query processing algorithm using a POI-based materialization technique so that we can process closest pairs and e-distance join queries in an efficient way. In addition, we show the retrieval efficiency of the proposed algorithms by making a performance comparison of the conventional algorithms.

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A Study on the Relationship between Milk Consumption, Dietary Nutrient Intake and Physical Strength of Adolescents in Middle and Small-Sized Cities in Korea for Dietary Education of Home Economics Subject at Middle and High Schools (중등학교 가정교과 식생활교육을 위한 청소년의 우유 섭취, 영양 섭취 및 체력과의 관계 연구)

  • Kim, Sun-Hyo
    • Journal of Korean Home Economics Education Association
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    • v.28 no.4
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    • pp.159-167
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    • 2016
  • This study was performed to investigate the relationship between milk consumption, dietary nutrient intake, and physical strength in Korean adolescents for dietary education of home economics subject at middle and high schools. Intake of milk and milk products, that of dietary nutrients, and physical strength records were surveyed for 298 high school students resided in small and medium-sized cities in Korea. Intake of milk and milk products was collected from three-day dietary survey, and daily dairy equivalent of calcium was calculated by dividing daily calcium intake(mg) from milk and milk products by calcium content(200 mg) of 200 mL milk. Dietary survey was performed during three days including two-weekdays and one-weekend by food record method. Dietary nutrient intake was analyzed by CAN-Pro 3.0. Physical strength records were offered from subjects' schools. Subjects were divided into low intake group(${\leq}0.29/d$), medium intake group(0.30-0.78/d) and high intake group(0.79-5.66/d) according to daily mean dairy equivalent of calcium taken by them, and most of them consumed milk and milk products less than '2' of the recommended value. Daily mean dairy equivalent of calcium was significantly related with high records of '50 m running' and 'stand long jump'(p<0.05), however it was not related with other records of physical strength. Intakes of energy, carbohydrate, protein, fat, calcium, phosphorus, iron, zinc, thiamin, riboflavin, niacin and vitamin E were significantly correlated with high record of '50 m running'(p<0.01). Intakes of nutrients were related with '50 m running' except fat were significantly correlated with high record of 'stand long jump'(p<0.05). Intakes of protein, phosphorus, iron, zinc, vitamin A, $B_6$ and E were significantly correlated with high record of 'long distance running'(p<0.05). In conclusion intake of milk and milk products was related with physical strength records('50 m running' and 'stand long jump') and intakes of most nutrients including energy nutrient, vitamin and mineral were correlated with physical strength records('50 m running', 'stand long jump' and 'long distance running') in Korean adolescents. Therefore, optimal consumption of milk and various nutrients for balanced nutrition during adolescents should be emphasized in dietary education of home economics subject for their strong physical strength.