• Title/Summary/Keyword: Data pooling

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Improving Usage of the Korea Meteorological Administration's Digital Forecasts in Agriculture: I. Correction for Local Temperature under the Inversion Condition (기상청 동네예보의 영농활용도 증진을 위한 방안: I. 기온역전조건의 국지기온 보정)

  • Kim, Soo-Ock;Kim, Dae-Jun;Kim, Jin-Hee;Yun, Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.15 no.2
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    • pp.76-84
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    • 2013
  • An adequate downscaling of the official forecasts of Korea Meteorological Administration (KMA) is a prerequisite to improving the value and utility of agrometeorological information in rural areas, where complex terrain and small farms constitute major features of the landscape. In this study, we suggest a simple correction scheme for scaling down the KMA temperature forecasts from mesoscale (5 km by 5 km) to the local scale (30 m by 30 m) across a rural catchment, especially under temperature inversion conditions. The study area is a rural catchment of $50km^2$ area with complex terrain and located on a southern slope of Mountain Jiri National Park. Temperature forecasts for 0600 LST on 62 days with temperature inversion were selected from the fall 2011-spring 2012 KMA data archive. A geospatial correction scheme which can simulate both cold air drainage and the so-called 'thermal belt' was used to derive the site-specific temperature deviation across the study area at a 30 m by 30 m resolution from the original 5 km by 5 km forecast grids. The observed temperature data at 12 validation sites within the study area showed a substantial reduction in forecast error: from ${\pm}2^{\circ}C$ to ${\pm}1^{\circ}C$ in the mean error range and from $1.9^{\circ}C$ to $1.6^{\circ}C$ in the root mean square error. Improvement was most remarkable at low lying locations showing frequent cold pooling events. Temperature prediction error was less than $2^{\circ}C$ for more than 80% of the observed inversion cases and less than $1^{\circ}C$ for half of the cases. Temperature forecasts corrected by this scheme may accelerate implementation of the freeze and frost early warning service for major fruits growing regions in Korea.

Exploratory Case Study for Key Successful Factors of Producy Service System (Product-Service System(PSS) 성공과 실패요인에 관한 탐색적 사례 연구)

  • Park, A-Rum;Jin, Dong-Su;Lee, Kyoung-Jun
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.255-277
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    • 2011
  • Product Service System(PSS), which is an integrated combination of product and service, provides new value to customer and makes companies sustainable as well. The objective of this paper draws Critical Successful Factors(CSF) of PSS through multiple case study. First, we review various concepts and types in PSS and Platform business literature currently available on this topic. Second, after investigating various cases with the characteristics of PSS and platform business, we select four cases of 'iPod of Apple', 'Kindle of Amazon', 'Zune of Microsoft', and 'e-book reader of Sony'. Then, the four cases are categorized as successful and failed cases according to criteria of case selection and PSS classification. We consider two methodologies for the case selection, i.e., 'Strategies for the Selection of Samples and Cases' proposed by Bent(2006) and the seven case selection procedures proposed by Jason and John(2008). For case selection, 'Stratified sample and Paradigmatic cases' is adopted as one of several options for sampling. Then, we use the seven case selection procedures such as 'typical', 'diverse', 'extreme', 'deviant', 'influential', 'most-similar', and 'mostdifferent' and among them only three procedures of 'diverse', 'most?similar', and 'most-different' are applied for the case selection. For PSS classification, the eight PSS types, suggested by Tukker(2004), of 'product related', 'advice and consulancy', 'product lease', 'product renting/sharing', 'product pooling', 'activity management', 'pay per service unit', 'functional result' are utilized. We categorize the four selected cases as a product oriented group because the cases not only sell a product, but also offer service needed during the use phase of the product. Then, we analyze the four cases by using cross-case pattern that Eisenhardt(1991) suggested. Eisenhardt(1991) argued that three processes are required for avoiding reaching premature or even false conclusion. The fist step includes selecting categories of dimensions and finding within-group similarities coupled with intergroup difference. In the second process, pairs of cases are selected and listed. The second step forces researchers to find the subtle similarities and differences between cases. The third process is to divide the data by data source. The result of cross-case pattern indicates that the similarities of iPod and Kindle as successful cases are convenient user interface, successful plarform strategy, and rich contents. The differences between the successful cases are that, wheares iPod has been recognized as the culture code, Kindle has implemented a low price as its main strategy. Meanwhile, the similarities of Zune and PRS series as failed cases are lack of sufficient applications and contents. The differences between the failed cases are that, wheares Zune adopted an undifferentiated strategy, PRS series conducted high-price strategy. From the analysis of the cases, we generate three hypotheses. The first hypothesis assumes that a successful PSS system requires convenient user interface. The second hypothesis assumes that a successful PSS system requires a reciprocal(win/win) business model. The third hypothesis assumes that a successful PSS system requires sufficient quantities of applications and contents. To verify the hypotheses, we uses the cross-matching (or pattern matching) methodology. The methodology matches three key words (user interface, reciprocal business model, contents) of the hypotheses to the previous papers related to PSS, digital contents, and Information System (IS). Finally, this paper suggests the three implications from analyzed results. A successful PSS system needs to provide differentiated value for customers such as convenient user interface, e.g., the simple design of iTunes (iPod) and the provision of connection to Kindle Store without any charge. A successful PSS system also requires a mutually benefitable business model as Apple and Amazon implement a policy that provides a reasonable proft sharing for third party. A successful PSS system requires sufficient quantities of applications and contents.

Preliminary analysis of metabolic syndrome components in Korean adolescents by using Korean national health and nutrition examination Survey pooling data (1998, 2001, and 2005) (한국국민건강영양조사 병합자료(1998년, 2001년, 2005년)를 이용한 소아청소년에서의 대사증후군 진단 요인의 기초 분석)

  • Huh, Kyoung;Park, Mi Jung
    • Clinical and Experimental Pediatrics
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    • v.51 no.12
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    • pp.1300-1309
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    • 2008
  • Purpose :This study aimed to estimate age- and gender-specific cut points for metabolic syndrome (MS) components, including body mass index (BMI), blood pressure (BP), triglycerides, high-density lipoprotein (HDL) cholesterol, and glucose. Methods :Data from the 1998, 2001, and 2005 Korean NHANES (National Health and Nutrition Examination Survey) were analyzed (n=4164; 2,139 boys and 2,025 girls, aged 10-19 years). Height, weight, waist circumference (WC), BP, triglycerides, HDL cholesterol, and fasting glucose were measured. Results :BMI over $25kg/m^2$ represents the $85^{th}P$ (percentile) in 17-year-old boys and the $90^{th}P$ in 17-year-old girls. A level of WC higher than that of the cutoff points of Asian adults was found in the $90^{th}P$ of 17-year-old boys and girls. The $90^{th}P$ of boys aged 15 years old and the $95^{th}P$ of 13-year-old were included in the range of systolic BP over 130 mm Hg. Over the $75^{th}P$ of the group showed triglycerides greater than 110 mg/dL, (criterion of MS presented by NCEP-ATP III) and the $90^{th}P$ of the group showed triglycerides greater than 150 mg/dL by IDF. An HDL cholesterol level of 40 mg/dL represents the $25^{th}P$ in boys and the $10^{th}P$ in girls. A glucose level greater than 110 mg/dL represents the $95^{th}P$ and greater than 100 mg/dL represents the $90^{th}P$. Conclusion :Values of the $90^{th}P$ of MS components in late adolescent boys (WC, BP, and triglycerides) and girls (WC and triglycerides) were very high and in close proximity to the diagnostic criteria of adult MS.

Target-Aspect-Sentiment Joint Detection with CNN Auxiliary Loss for Aspect-Based Sentiment Analysis (CNN 보조 손실을 이용한 차원 기반 감성 분석)

  • Jeon, Min Jin;Hwang, Ji Won;Kim, Jong Woo
    • Journal of Intelligence and Information Systems
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    • v.27 no.4
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    • pp.1-22
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    • 2021
  • Aspect Based Sentiment Analysis (ABSA), which analyzes sentiment based on aspects that appear in the text, is drawing attention because it can be used in various business industries. ABSA is a study that analyzes sentiment by aspects for multiple aspects that a text has. It is being studied in various forms depending on the purpose, such as analyzing all targets or just aspects and sentiments. Here, the aspect refers to the property of a target, and the target refers to the text that causes the sentiment. For example, for restaurant reviews, you could set the aspect into food taste, food price, quality of service, mood of the restaurant, etc. Also, if there is a review that says, "The pasta was delicious, but the salad was not," the words "steak" and "salad," which are directly mentioned in the sentence, become the "target." So far, in ABSA, most studies have analyzed sentiment only based on aspects or targets. However, even with the same aspects or targets, sentiment analysis may be inaccurate. Instances would be when aspects or sentiment are divided or when sentiment exists without a target. For example, sentences like, "Pizza and the salad were good, but the steak was disappointing." Although the aspect of this sentence is limited to "food," conflicting sentiments coexist. In addition, in the case of sentences such as "Shrimp was delicious, but the price was extravagant," although the target here is "shrimp," there are opposite sentiments coexisting that are dependent on the aspect. Finally, in sentences like "The food arrived too late and is cold now." there is no target (NULL), but it transmits a negative sentiment toward the aspect "service." Like this, failure to consider both aspects and targets - when sentiment or aspect is divided or when sentiment exists without a target - creates a dual dependency problem. To address this problem, this research analyzes sentiment by considering both aspects and targets (Target-Aspect-Sentiment Detection, hereby TASD). This study detected the limitations of existing research in the field of TASD: local contexts are not fully captured, and the number of epochs and batch size dramatically lowers the F1-score. The current model excels in spotting overall context and relations between each word. However, it struggles with phrases in the local context and is relatively slow when learning. Therefore, this study tries to improve the model's performance. To achieve the objective of this research, we additionally used auxiliary loss in aspect-sentiment classification by constructing CNN(Convolutional Neural Network) layers parallel to existing models. If existing models have analyzed aspect-sentiment through BERT encoding, Pooler, and Linear layers, this research added CNN layer-adaptive average pooling to existing models, and learning was progressed by adding additional loss values for aspect-sentiment to existing loss. In other words, when learning, the auxiliary loss, computed through CNN layers, allowed the local context to be captured more fitted. After learning, the model is designed to do aspect-sentiment analysis through the existing method. To evaluate the performance of this model, two datasets, SemEval-2015 task 12 and SemEval-2016 task 5, were used and the f1-score increased compared to the existing models. When the batch was 8 and epoch was 5, the difference was largest between the F1-score of existing models and this study with 29 and 45, respectively. Even when batch and epoch were adjusted, the F1-scores were higher than the existing models. It can be said that even when the batch and epoch numbers were small, they can be learned effectively compared to the existing models. Therefore, it can be useful in situations where resources are limited. Through this study, aspect-based sentiments can be more accurately analyzed. Through various uses in business, such as development or establishing marketing strategies, both consumers and sellers will be able to make efficient decisions. In addition, it is believed that the model can be fully learned and utilized by small businesses, those that do not have much data, given that they use a pre-training model and recorded a relatively high F1-score even with limited resources.