• Title/Summary/Keyword: Evaluation Services

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Predicting the Direction of the Stock Index by Using a Domain-Specific Sentiment Dictionary (주가지수 방향성 예측을 위한 주제지향 감성사전 구축 방안)

  • Yu, Eunji;Kim, Yoosin;Kim, Namgyu;Jeong, Seung Ryul
    • Journal of Intelligence and Information Systems
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    • v.19 no.1
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    • pp.95-110
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    • 2013
  • Recently, the amount of unstructured data being generated through a variety of social media has been increasing rapidly, resulting in the increasing need to collect, store, search for, analyze, and visualize this data. This kind of data cannot be handled appropriately by using the traditional methodologies usually used for analyzing structured data because of its vast volume and unstructured nature. In this situation, many attempts are being made to analyze unstructured data such as text files and log files through various commercial or noncommercial analytical tools. Among the various contemporary issues dealt with in the literature of unstructured text data analysis, the concepts and techniques of opinion mining have been attracting much attention from pioneer researchers and business practitioners. Opinion mining or sentiment analysis refers to a series of processes that analyze participants' opinions, sentiments, evaluations, attitudes, and emotions about selected products, services, organizations, social issues, and so on. In other words, many attempts based on various opinion mining techniques are being made to resolve complicated issues that could not have otherwise been solved by existing traditional approaches. One of the most representative attempts using the opinion mining technique may be the recent research that proposed an intelligent model for predicting the direction of the stock index. This model works mainly on the basis of opinions extracted from an overwhelming number of economic news repots. News content published on various media is obviously a traditional example of unstructured text data. Every day, a large volume of new content is created, digitalized, and subsequently distributed to us via online or offline channels. Many studies have revealed that we make better decisions on political, economic, and social issues by analyzing news and other related information. In this sense, we expect to predict the fluctuation of stock markets partly by analyzing the relationship between economic news reports and the pattern of stock prices. So far, in the literature on opinion mining, most studies including ours have utilized a sentiment dictionary to elicit sentiment polarity or sentiment value from a large number of documents. A sentiment dictionary consists of pairs of selected words and their sentiment values. Sentiment classifiers refer to the dictionary to formulate the sentiment polarity of words, sentences in a document, and the whole document. However, most traditional approaches have common limitations in that they do not consider the flexibility of sentiment polarity, that is, the sentiment polarity or sentiment value of a word is fixed and cannot be changed in a traditional sentiment dictionary. In the real world, however, the sentiment polarity of a word can vary depending on the time, situation, and purpose of the analysis. It can also be contradictory in nature. The flexibility of sentiment polarity motivated us to conduct this study. In this paper, we have stated that sentiment polarity should be assigned, not merely on the basis of the inherent meaning of a word but on the basis of its ad hoc meaning within a particular context. To implement our idea, we presented an intelligent investment decision-support model based on opinion mining that performs the scrapping and parsing of massive volumes of economic news on the web, tags sentiment words, classifies sentiment polarity of the news, and finally predicts the direction of the next day's stock index. In addition, we applied a domain-specific sentiment dictionary instead of a general purpose one to classify each piece of news as either positive or negative. For the purpose of performance evaluation, we performed intensive experiments and investigated the prediction accuracy of our model. For the experiments to predict the direction of the stock index, we gathered and analyzed 1,072 articles about stock markets published by "M" and "E" media between July 2011 and September 2011.

A Study on the Evaluation of Fertilizer Loss in the Drainage(Waste) Water of Hydroponic Cultivation, Korea (수경재배 유출 배액(폐양액)의 비료 손실량 평가 연구)

  • Jinkwan Son;Sungwook Yun;Jinkyung Kwon;Jihoon Shin;Donghyeon Kang;Minjung Park;Ryugap Lim
    • Journal of Wetlands Research
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    • v.25 no.1
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    • pp.35-47
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    • 2023
  • Korean facility horticulture and hydroponic cultivation methods increase, requiring the management of waste water generated. In this study, the amount of fertilizer contained in the discharged waste liquid was determined. By evaluating this as a price, it was suggested to reduce water treatment costs and recycle fertilizer components. It was evaluated based on the results of major water quality analysis of waste liquid by crop, such as tomatoes, paprika, cucumbers, and strawberries, and in the case of P component, it was analyzed by converting it to the amount of phosphoric acid (P2O5). The amount of nitrogen (N) can be calculated by discharging 1,145.90kg·ha-1 of tomatoes, 920.43kg·ha-1 of paprika, 804.16kg·ha-1 of cucumbers, 405.83kg·ha-1 of strawberries, and the fertilizer content of P2O5 is 830.65kg·ha-1 of paprika, 622.32kg·ha-1 of tomatoes, 477.67kg·ha-1 of cucumbers. In addition, trace elements such as potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and manganese (Mn) were also analyzed to be emitted. The price per kg of each item calculated by averaging the price of fertilizer sold on the market can be evaluated as KRW, N 860.7, P 2,378.2, K 2,121.7, Ca 981.2, Mg 1,036.3, Fe 126,076.9, Mn 62,322.1, Zn 15,825.0, Cu 31,362.0, B 4,238.0, Mo 149,041.7. The annual fertilizer loss amount for each crop was calculated by comprehensively considering the price per kg calculated based on the market price of fertilizer, the concentration of waste by crop analyzed earlier, and the average annual emission of hydroponic cultivation. As a result of the analysis, the average of the four hydroponic crops was 5,475,361.1 won in fertilizer ingredients, with tomatoes valued at 6,995,622.3 won, paprika valued at 7,384,923.8 won, cucumbers valued at 5,091,607.9 won, and strawberries valued at 2,429,290.6 won. It was expected that if hydroponic drainage is managed through self-treatment or threshing before discharge rather than by leaking it into a river and treating it as a pollutant, it can be a valuable reusable fertilizer ingredient along with reducing water treatment costs.

The Evaluation of Food Service Menus in an Immigration Detention Center (외국인 보호소 급식 식단 품질에 대한 인식 및 만족도)

  • Kim, Hye-Jin;Kim, Woon Joo;Lee, Young Eun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.2
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    • pp.286-305
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    • 2013
  • The purpose of this study was to investigate the recognition and satisfaction with the menu quality of food services in an immigration detention center. The survey was conducted from January 22, 2010 to April 22, 2010 by questionnaires. A survey with 265 respondents was conducted and data analyzed by the SAS Program. In analyzing leftovers, the most common was kimchi (37.61%), followed by breads (21.52%), and beans/bean curd (17.99%). The common cause for leftover were undesirable taste (31.84%), sickness or a lack of desire for eating (19.85%). In terms of cooking methods, stir-frying, broiling, and frying were highly preferred to steaming, boiling, and salting. In the analysis of preferences in the taste and satisfaction of food service, there were significant differences in hot, sour, bitter, and light tastes (p<0.05, p<0.01, p<0.001). Satisfaction was low with hot and light tastes, whereas sour and the bitter tastes showed a high degree of satisfaction. In the opinions for quality improvement, most immigrants wanted a tastier food supply (58.69%), a diverse food supply (40.54%), and clean utensils (36.68%). In the analysis of the gap between importance and performance, food taste, variety, and sanitation were recognized as poorly performed, causing major dissatisfaction with the food. The overall satisfaction score was 'average' (3 points out of 5 points) with 3.26 points. The satisfaction score showed insignificant difference depending on religions and duration of stay in Korea, but showed significant differences depending on nationality (p<0.001).