• Title/Summary/Keyword: Long-term Time Series

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A Study of Selection of the Growth Potential Agricultural Products in Ulsan City (지역농산물의 성장 유망 작목의 선정을 위한 연구 - 울산시를 중심으로 -)

  • Kim, Chul-Wook;Kim, Tae-Wan
    • Journal of agriculture & life science
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    • v.46 no.1
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    • pp.207-215
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    • 2012
  • In this study, we performed to select the high growth potential agri-products in Ulsan City, Korea. For this, we carried out the location quotient and the regional growth rate differential analyses using the cultivated area data and the agricultural output data in 2000, 2005 and 2007. The location quotient analysis revealed that rice, pear and persimmon were classified as specialized agri-products. These results would be useful to reflect on a short-term policy in support for the agricultural activities of the local farmers because the specialized agri-products occupy a relatively high proportion in the region. In addition, the regional growth rate differential analysis showed that strawberries, persimmon, potatoes, corn and sweet potato are classified as growing agri-products whereas pear is classified as a competitive agri-product in the analysis based on agricultural output from 2000 to 2007. Based on cultivated area, strawberries, potatoes and corn are classified as growing agri-products whereas sweet potato is classified as a competitive agri-product. These results would be beneficial to establish a long-term agricultural policy in Ulsan City because these agri-products are further supported by the time series analysis, considering the nationwide trends and the production activities reflecting the preferences of consumers and the willingness of producers.

Development the Geostationary Ocean Color Imager (GOCI) Data Processing System (GDPS) (정지궤도 해색탑재체(GOCI) 해양자료처리시스템(GDPS)의 개발)

  • Han, Hee-Jeong;Ryu, Joo-Hyung;Ahn, Yu-Hwan
    • Korean Journal of Remote Sensing
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    • v.26 no.2
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    • pp.239-249
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    • 2010
  • The Geostationary Ocean Color Imager (GOCI) data-processing system (GDPS), which is a software system for satellite data processing and analysis of the first geostationary ocean color observation satellite, has been developed concurrently with the development of th satellite. The GDPS has functions to generate level 2 and 3 oceanographic analytical data, from level 1B data that comprise the total radiance information, by programming a specialized atmospheric algorithm and oceanic analytical algorithms to the software module. The GDPS will be a multiversion system not only as a standard Korea Ocean Satellite Center(KOSC) operational system, but also as a basic GOCI data-processing system for researchers and other users. Additionally, the GDPS will be used to make the GOCI images available for distribution by satellite network, to calculate the lookup table for radiometric calibration coefficients, to divide/mosaic several region images, to analyze time-series satellite data. the developed GDPS system has satisfied the user requirement to complete data production within 30 minutes. This system is expected to be able to be an excellent tool for monitoring both long-term and short-term changes of ocean environmental characteristics.

Effect of El Niño and La Niña on the Coastal Upwelling in East Sea, South Korea (엘니뇨와 라니냐가 한국 동해 연안용승에 미치는 영향)

  • Seo, Ho-San;Kim, Dong-Sun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.1
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    • pp.75-83
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    • 2020
  • This study investigated the effects of El Niño and La Niña on coastal upwelling in the East Sea of Korea using long-term (1967-2017) water temperature observation data and Oceanic Niño Index (ONI). As a result of time series analysis of water temperature, the occurrence frequency of summer coastal upwelling was the highest in the southeastern (Ulgi ~ Gimpo) coast. In 1987-1988 and 1997-1998, when the annual fluctuations of ONI plunged more than 2.5, the water temperature in whole coast areas of the East Sea (Busan ~ Goseung) rose by 4 ~ 7 ℃. The temperature structure of the East Sea coastal water was different when El Niño was strong with ONI above 1.5 and La Niña with strong ONI below -0.8. When El Niño is strong, the water temperature anomaly in coastal waters is negative. This is due to the strong baroclinic tilting and the formation of shallow temperature stratification in the coastal waters. The strong La Niña season is opposite to the strong El Niño season, whereas the water temperature anomaly is positive. In addition, the baroclinic tilting is weaker than the time of strong El Niño and the temperature stratification is formed deeper than the time of strong El Niño. The formation of temperature stratification at shallow depths when El Niño is strong can increase the probability of occurrence coastal upwelling caused by southerly winds in the summer season. On the contrary, when La Niña is strong, occurrence of coastal upwelling is less likely even if the southerly wind blows continuously. This is because the temperature stratification is formed at deeper than when El Niño is strong.

Prediction of a hit drama with a pattern analysis on early viewing ratings (초기 시청시간 패턴 분석을 통한 대흥행 드라마 예측)

  • Nam, Kihwan;Seong, Nohyoon
    • Journal of Intelligence and Information Systems
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    • v.24 no.4
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    • pp.33-49
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    • 2018
  • The impact of TV Drama success on TV Rating and the channel promotion effectiveness is very high. The cultural and business impact has been also demonstrated through the Korean Wave. Therefore, the early prediction of the blockbuster success of TV Drama is very important from the strategic perspective of the media industry. Previous studies have tried to predict the audience ratings and success of drama based on various methods. However, most of the studies have made simple predictions using intuitive methods such as the main actor and time zone. These studies have limitations in predicting. In this study, we propose a model for predicting the popularity of drama by analyzing the customer's viewing pattern based on various theories. This is not only a theoretical contribution but also has a contribution from the practical point of view that can be used in actual broadcasting companies. In this study, we collected data of 280 TV mini-series dramas, broadcasted over the terrestrial channels for 10 years from 2003 to 2012. From the data, we selected the most highly ranked and the least highly ranked 45 TV drama and analyzed the viewing patterns of them by 11-step. The various assumptions and conditions for modeling are based on existing studies, or by the opinions of actual broadcasters and by data mining techniques. Then, we developed a prediction model by measuring the viewing-time distance (difference) using Euclidean and Correlation method, which is termed in our study similarity (the sum of distance). Through the similarity measure, we predicted the success of dramas from the viewer's initial viewing-time pattern distribution using 1~5 episodes. In order to confirm that the model is shaken according to the measurement method, various distance measurement methods were applied and the model was checked for its dryness. And when the model was established, we could make a more predictive model using a grid search. Furthermore, we classified the viewers who had watched TV drama more than 70% of the total airtime as the "passionate viewer" when a new drama is broadcasted. Then we compared the drama's passionate viewer percentage the most highly ranked and the least highly ranked dramas. So that we can determine the possibility of blockbuster TV mini-series. We find that the initial viewing-time pattern is the key factor for the prediction of blockbuster dramas. From our model, block-buster dramas were correctly classified with the 75.47% accuracy with the initial viewing-time pattern analysis. This paper shows high prediction rate while suggesting audience rating method different from existing ones. Currently, broadcasters rely heavily on some famous actors called so-called star systems, so they are in more severe competition than ever due to rising production costs of broadcasting programs, long-term recession, aggressive investment in comprehensive programming channels and large corporations. Everyone is in a financially difficult situation. The basic revenue model of these broadcasters is advertising, and the execution of advertising is based on audience rating as a basic index. In the drama, there is uncertainty in the drama market that it is difficult to forecast the demand due to the nature of the commodity, while the drama market has a high financial contribution in the success of various contents of the broadcasting company. Therefore, to minimize the risk of failure. Thus, by analyzing the distribution of the first-time viewing time, it can be a practical help to establish a response strategy (organization/ marketing/story change, etc.) of the related company. Also, in this paper, we found that the behavior of the audience is crucial to the success of the program. In this paper, we define TV viewing as a measure of how enthusiastically watching TV is watched. We can predict the success of the program successfully by calculating the loyalty of the customer with the hot blood. This way of calculating loyalty can also be used to calculate loyalty to various platforms. It can also be used for marketing programs such as highlights, script previews, making movies, characters, games, and other marketing projects.

A Two-Phase Hybrid Stock Price Forecasting Model : Cointegration Tests and Artificial Neural Networks (2단계 하이브리드 주가 예측 모델 : 공적분 검정과 인공 신경망)

  • Oh, Yu-Jin;Kim, Yu-Seop
    • The KIPS Transactions:PartB
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    • v.14B no.7
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    • pp.531-540
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    • 2007
  • In this research, we proposed a two-phase hybrid stock price forecasting model with cointegration tests and artificial neural networks. Using not only the related stocks to the target stock but also the past information as input features in neural networks, the new model showed an improved performance in forecasting than that of the usual neural networks. Firstly in order to extract stocks which have long run relationships with the target stock, we made use of Johansen's cointegration test. In stock market, some stocks are apt to vary similarly and these phenomenon can be very informative to forecast the target stock. Johansen's cointegration test provides whether variables are related and whether the relationship is statistically significant. Secondly, we learned the model which includes lagged variables of the target and related stocks in addition to other characteristics of them. Although former research usually did not incorporate those variables, it is well known that most economic time series data are depend on its past value. Also, it is common in econometric literatures to consider lagged values as dependent variables. We implemented a price direction forecasting system for KOSPI index to examine the performance of the proposed model. As the result, our model had 11.29% higher forecasting accuracy on average than the model learned without cointegration test and also showed 10.59% higher on average than the model which randomly selected stocks to make the size of the feature set same as that of the proposed model.

Correction of Prominent Alar Lobule by Resecting Dilator Naris Muscles-A Pilot Study (콧구멍 확대근의 절제를 통한 넓은 콧방울의 교정-예비 보고)

  • Shin, Soo-Hye;Park, Hyun;Han, Seung-Kyu;Kim, Woo-Kyung
    • Archives of Plastic Surgery
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    • v.38 no.5
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    • pp.669-673
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    • 2011
  • Purpose: The authors have conducted a series of anatomic studies on the factors affecting shape of a lower vault in Asian noses. The results of the studies showed that prominence of alar lobule is mainly affected by the volumes of the dilator naris anterior and posterior muscles and the insertions of the dilator naris posterior muscles. However, information on its clinical availability is yet insufficient. The present study was undertaken for clinical purpose to find out the effect of dilator naris muscle resection on the correction of prominent alar lobule. Methods: Six patients who were treated by dilator naris muscle resection with a long-term follow-up of more than 1 year were involved in this study. Rhinoplasties were performed via endonasal approaches with resecting dilator naris anterior and posterior muscles by sharp scissor. The effect of the dilator naris muscle resection on alar prominence was investigated by measuring ratio of the short axis to the long axis of a nostril (SA/LA) pre-and postoperatively. The visual analog scale (VAS) was also used to evaluate satisfaction of patients. An average follow-up time was $15.6{\pm}3.7$ months. Results: Having lost the dilating and lateral pulling effects of the dilator naris muscles, the alar lobule shifted medially and alar lobule shapes improved. SA/LA significantly improved (preoperatively $0.71{\pm}0.11$ and postoperatively $0.58{\pm}0.08$; $p$ <0.05). The VAS score was also increased postoperatively (preoperatively $3.2{\pm}1.8$ and postoperatively $8.7{\pm}1.2$; $p$ <0.05). A mild degree of hyperpigmented scar was noted in one alar lobule. Otherwise, there was no case of postoperative complication. Conclusion: Our results suggest that prominent alar lobule could be modified by resecting the attachment of the dilator naris muscles. This maneuver removes the function of dilator naris muscles, then may produce a more aesthetically acceptable alar lobule shape.

Variation of Nutrients due to Long-Term Effects of Ocean Dumping and Spatial Variability of Water Quality Parameters in Summer at the Ocean Waste Disposal Site Off the West Coast of Korea (한국 서해 폐기물 투기해역의 하계 수질인자 분포특성과 장기 투기행위로 인한 영양염 농도 변화)

  • Koh, Hyuk Joon;Choi, Young Chan;Park, Sung Eun;Cha, Hyung Kee;Chang, Dae Soo;Yoon, Han Sam;Lee, Chung Il
    • Journal of Environmental Science International
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    • v.22 no.11
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    • pp.1389-1402
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    • 2013
  • This paper focuses on the impacts of waste dumping on inorganic nutrients in the dumping area of the Yellow Sea, and the effect of an governmental regulation of pollution in dumping areas. The environmental variables and parameters of the dumping and reference areas in the Yellow Sea were measured during July 2009 and analyzed. In addition, the analyzed data for inorganic nutrients over the last 10 years were obtained from the Korea Coast Guard (KCG) and the National Fisheries Research and Development Institute (NFRDI). The chemical environment of the study area revealed increases in concentrations of inorganic nutrients, Chemical Oxygen Demand (COD), and Volatile Suspended Solids (VSS) in the bottom layer. On the contrary, the pH level was decreased. Most notably, the time series data of inorganic nutrients showed gradual increase over time in the dumping area, and thus, the oligotrophic waters trend toward eutrophic waters. The increases appears to be due to the disposal of large amounts of organic waste. In recent times, the wastes disposed at the area were largely comprised of livestock wastewater, and food processing waste water. The liquefied waste, which contains an abundance of nutrients, causes a sharp increase in concentrations of inorganic nitrogen in the dumping area. On the one hand, the dumping sites have been deteriorated to such an extent that pollution has become a social problem. Consequentially, the government had a regulatory policy for improvement of marine environmental since 2007 in the dumping area. Hence, the quality of marine water in the dumping site has improved.

Spontaneous bone regeneration after surgical extraction of a horizontally impacted mandibular third molar: a retrospective panoramic radiograph analysis

  • Kim, Eugene;Eo, Mi Young;Nguyen, Truc Thi Hoang;Yang, Hoon Joo;Myoung, Hoon;Kim, Soung Min
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.41
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    • pp.4.1-4.10
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    • 2019
  • Background: The mandibular third molar (M3) is typically the last permanent tooth to erupt because of insufficient space and thick soft tissues covering its surface. Problems such as alveolar bone loss, development of a periodontal pocket, exposure of cementum, gingival recession, and dental caries can be found in the adjacent second molars (M2) following M3 extraction. The specific aims of the study were to assess the amount and rate of bone regeneration on the distal surface of M2 and to evaluate the aspects of bone regeneration in terms of varying degree of impaction. Methods: Four series of panoramic radiographic images were obtained from the selected cases, including images from the first visit, immediately after extraction, 6 weeks, and 6 months after extraction. ImageJ software® (NIH, USA) was used to measure linear distance from the region of interest to the distal root of the adjacent M2. Radiographic infrabony defect (RID) values were calculated from the measured radiographic bone height and cementoenamel junction with distortion compensation. Repeated measures of analysis of variance and one-way analysis of variance were conducted to analyze the statistical significant difference between RID and time, and a Spearman correlation test was conducted to assess the relationship between Pederson's difficulty index (DI) and RID. Results: A large RID (> 6 mm) can be reduced gradually and consistently over time. More than half of the samples recovered nearly to their normal healthy condition (RID ≤ 3 mm) by the 6-month follow-up. DI affected the first 6 weeks of post-extraction period and only showed a significant positive correlation with respect to the difference between baseline and final RID. Conclusions: Additional treatments on M2 for a minimum of 6 months after an M3 extraction could be recommended. Although DI may affect bone regeneration during the early healing period, further study is required to elucidate any possible factors associated with the healing process. The DI does not cause any long-term adverse effects on bone regeneration after surgical extraction.

A Meta-Analysis of Air Pollution in Relation to Daily Mortality in Seven Major Cities of Korea, 1998-2001 (메타분석을 적용한 전국 7개 대도시의 대기오염과 일일사망발생의 상관성 연구(1998년$\sim$2001년))

  • Cho, Yong-Sung;Lee, Jong-Tae;Son, Ji-Young;Kim, Yoon-Shin
    • Journal of Environmental Health Sciences
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    • v.32 no.4 s.91
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    • pp.304-315
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    • 2006
  • This study is performed to reexamine the association between ambient air pollution and daily mortality in seven major cities of Korea using a method of meta-analysis with the data filed for the period 1998-2001. These cities account for half of the Korean population (about 23 million). The observed concentrations of carbon monoxide (CO, mean=1.08 ppm), ozone ($O_3$, mean=33.97 ppb), particulate matter less than 10 ${\mu}m$ ($PM_{10},\;mean=57.11\;{\mu}g/m^3$), nitrogen dioxide ($NO_2$, mean=25.09 ppb), and sulfur dioxide ($SO_2$, mean=9.14 ppb) during the study period were at levels below Korea's current ambient air quality standards. Generalized additive models were applied to allow for the highly flexible fitting of seasonal and long-term time trends in air pollution as well as nonlinear associations with weather variables, such as air temperature and relative humidity. Also, we calculated a weighted mean as a meta-analysis summary of the estimates and its standard error. In city-specific analyses, an increase of $41.17{\mu}g/m^3(IQR)\;of\;PM_{10}$ corresponded to $1{\sim}12%$ more deaths, given constant weather conditions. Like most of air pollution epidemiologic studies, this meta-analysis cannot avoid fleeing from measurement misclassification since no personal measurement was taken. However, we can expect that a measurement bias be reduced in district-specific estimate since a monitoring station is better representative of air quality of the matched district. Significant heterogeneity was found for the effect of all pollutants. The estimated relative risks from meta-like analysis increased compared to those relative risks from pooled analysis. The similar results to those from the previous studies indicated existence of health effect of air pollution at current levels in many industrialized countries, including Korea.

The Impact of CPO Characteristics on Organizational Privacy Performance (개인정보보호책임자의 특성이 개인정보보호 성과에 미치는 영향)

  • Wee, Jiyoung;Jang, Jaeyoung;Kim, Beomsoo
    • Asia pacific journal of information systems
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    • v.24 no.1
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    • pp.93-112
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    • 2014
  • As personal data breach reared up as a problem domestically and globally, organizations appointing chief privacy officers (CPOs) are increasing. Related Korean laws, 'Personal Data Protection Act' and 'the Act on Promotion of Information and Communication Network Utilization and Information Protection, etc.' require personal data processing organizations to appoint CPOs. Research on the characteristics and role of CPO is called for because of the importance of CPO being emphasized. There are many researches on top management's role and their impact on organizational performance using the Upper Echelon theory. This study investigates what influence the characteristics of CPO gives on the organizational privacy performance. CPO's definition varies depending on industry, organization size, required responsibility and power. This study defines CPO as 'a person who takes responsibility for all the duties on handling the organization's privacy,' This research assumes that CPO characteristics such as role, personality and background knowledge have an influence on the organizational privacy performance. This study applies the part relevant to the upper echelon's characteristics and performance of the executives (CEOs, CIOs etc.) for CPO. First, following Mintzberg and other managerial role classification, information, strategic, and diplomacy roles are defined as the role of CPO. Second, the "Big Five" taxonomy on individual's personality was suggested in 1990. Among these five personalities, extraversion and conscientiousness are drawn as the personality characteristics of CPO. Third, advance study suggests complex knowledge of technology, law and business is necessary for CPO. Technical, legal, and business background knowledge are drawn as the background knowledge of CPO. To test this model empirically, 120 samples of data collected from CPOs of domestic organizations are used. Factor analysis is carried out and convergent validity and discriminant validity were verified using SPSS and Smart PLS, and the causal relationships between the CPO's role, personality, background knowledge and the organizational privacy performance are analyzed as well. The result of the analysis shows that CPO's diplomacy role and strategic role have significant impacts on organizational privacy performance. This reveals that CPO's active communication with other organizations is needed. Differentiated privacy policy or strategy of organizations is also important. Legal background knowledge and technical background knowledge were also found to be significant determinants to organizational privacy performance. In addition, CPOs conscientiousness has a positive impact on organizational privacy performance. The practical implication of this study is as follows: First, the research can be a yardstick for judgment when companies select CPOs and vest authority in them. Second, not only companies but also CPOs can judge what ability they should concentrate on for development of their career relevant to their job through results of this research. Cultural social value, citizen's consensus on the right to privacy, expected CPO's role will change in process of time. In future study, long-term time-series analysis based research can reveal these changes and can also offer practical implications for government and private organization's policy making on information privacy.