• Title/Summary/Keyword: Time trend analysis

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A Development of Trend Analysis Models and a Process Integrating with GIS for Industrial Water Consumption Using Realtime Sensing Data (실시간 공업용수 추세패턴 모형개발 및 GIS 연계방안)

  • Kim, Seong-Hoon
    • Journal of Korean Society for Geospatial Information Science
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    • v.19 no.3
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    • pp.83-90
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    • 2011
  • The purpose of this study is to develop a series of trend analysis models for industrial water consumption and to propose a blueprint for the integration of the developed models with GIS. For the consumption data acquisition, a real-time sensing technique was adopted. Data were transformed from the field equipments to the management server in every 5 minutes. The data acquired were substituted to a polynomial formula selected. As a result, a series of models were developed for the consumption of each day. A series of validation processes were applied to the developed models and the models were finalized. Then the finalized models were transformed to the average models representing a day's average consumption or an average daily consumption of each month. Demand pattern analyses were fulfilled through the visualization of the finally derived models. It has founded out that the demand patterns show great consistency and, therefore, it is concluded that high probability of demand forecasting for a day or for a season is available. Also proposed is the integration with GIS as an IT tool by which the developed forecasting models are utilized.

Keyword networks in RJCC research - A co-word analysis and clustering - (RJCC 연구 키워드 네트워크 - 동시출현단어분석과 군집분석 -)

  • Seo, Hyun-Jin;Choi, Yeong-Hyeon;Oh, Seung-Taek;Lee, Kyu-Hye
    • The Research Journal of the Costume Culture
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    • v.27 no.3
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    • pp.193-205
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    • 2019
  • A trend analysis of research articles in a field of knowledge is significant because it can help in finding out the structural characteristics of the field and the future direction of research through observing change in a time series. We identified the structural characteristics and trends in text data (keywords) gathered from research articles which in itself is an important task in various research areas. The titles and keywords were crawled from research articles published from 2016 to 2018 in the Research Journal of the Costume Culture (RJCC), one of the representative Korean journal in the field of clothing and textile. After we extracted data comprising English titles and keywords from 195 published articles, we transformed it into a 1-mode matrix. We used measures from network analysis (i.e., link, strength, and degree centrality) for evaluating meaningful patterns and trends in the research on clothing and textile. NodeXL was used for visualizing the semantic network. This study observed change in the clothing and textile research trend. In addition to covering the core areas of the field, the subjects of research have been diversifying with every passing year and have evolved onto a developmental direction. The most studied area in articles published by the RJCC was fashion retailing/consumer psychology while aesthetic/historic and fashion industry/policy studies were covered to a more limited extent. We observed that most of the studies reflecting the identity of RJCC share subject keywords to a significant extent.

Investigation of Korean Precipitation Variability using EOFs and Cyclostationary EOFs (EOF와 CSEOF를 이용한 한반도 강수의 변동성 분석)

  • Kim, Gwang-Seob;Sun, Ming-Dong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1260-1264
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    • 2009
  • Precipitation time series is a mixture of complicate fluctuation and changes. The monthly precipitation data of 61 stations during 36 years (1973-2008) in Korea are comprehensively analyzed using the EOFs technique and CSEOFs technique respectively. The main motivation for employing this technique in the present study is to investigate the physical processes associated with the evolution of the precipitation from observation data. The twenty-five leading EOF modes account for 98.05% of the total monthly variance, and the first two modes account for 83.68% of total variation. The first mode exhibits traditional spatial pattern with annual cycle of corresponding PC time series and second mode shows strong North South gradient. In CSEOF analysis, the twenty-five leading CSEOF modes account for 98.58% of the total monthly variance, and the first two modes account for 78.69% of total variation, these first two patterns' spatial distribution show monthly spatial variation. The corresponding mode's PC time series reveals the annual cycle on a monthly time scale and long-term fluctuation and first mode's PC time series shows increasing linear trend which represents that spatial and temporal variability of first mode pattern has strengthened. Compared with the EOFs analysis, the CSEOFs analysis preferably exhibits the spatial distribution and temporal evolution characteristics and variability of Korean historical precipitation.

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An Analysis on Trend of Time Budgets of Korean Younger Generation (靑少年의 生活時間 使用變化傾向에 관한 硏究)

  • Lee, Chung-Duck
    • Journal of Families and Better Life
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    • v.9 no.1 s.17
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    • pp.203-221
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    • 1991
  • 1) The purpose of this study is to investigate the correlation between general social changes and time budgets of younger generation in Korea. 2) I use the statistics which appeared in the 'Studies of the Time Budgets of Korean people" carried out by the Korean Broadacasting system in 1981 and in 1990. 3) The result of this analysis may be summarized as the following : (1) Even in the cases of biologically necessary acts such as sleeping and eating, the average time used by Korean younger generation is remarkably influenced by general social changes. (2) It is in the cases of optional acts such as reading, listening music and enjoying a move that general social changes influence excessively the time Budgets of children and the youth. (3) It seems that time Budgets of Korean younger generation are losing their balance and rationally year after year during 1981 and 1990. For instance they spend too much time enjoying TV or popular music. 4) As a conclusion, I shall strongly suggest : (1) Parents and school teachers should pay more attention in their guidance of their Children or pupil concerning the importnace of the time Budgest. (2) the programmers of television and radio should consider sincerly the educational influence of their products.

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Correlation Analysis between Delay and Turnaround Time at Jeju International Airport (제주국제공항의 지연과 Turnaround Time 간의 상관관계 분석)

  • Lee, Choongsub;Kim, Dongsin;Kim, Hyewook;Baik, Hojong
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.30 no.1
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    • pp.1-11
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    • 2022
  • The capacity of Jeju International Airport has reached its limit due to a surge in air traffic demand such as passengers and cargo and the continuous expansion of Low Cost Carriers (LCC). Despite COVID-19 that has began in November 2019, Jeju International Airport still has continuous demand in terms of passenger and cargo transportation. As a result, it is undeniable that the delay rate also unexpectedly increased as the air traffic volume at Jeju International Airport continued to increase. In this study, the correlation between Turnaround Time and delay rates of national airlines is analyzed based on past flight data at Jeju International Airport, and the cumulative delay time trend for sampled airlines is compared with Turnaround Time. Through this study, it is expected to contribute to securing aircraft operation efficiency and on-time by analyzing delays related to Turnaround Time at Jeju International Airport.

An Analysis of IT Trends Using Tweet Data (트윗 데이터를 활용한 IT 트렌드 분석)

  • Yi, Jin Baek;Lee, Choong Kwon;Cha, Kyung Jin
    • Journal of Intelligence and Information Systems
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    • v.21 no.1
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    • pp.143-159
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    • 2015
  • Predicting IT trends has been a long and important subject for information systems research. IT trend prediction makes it possible to acknowledge emerging eras of innovation and allocate budgets to prepare against rapidly changing technological trends. Towards the end of each year, various domestic and global organizations predict and announce IT trends for the following year. For example, Gartner Predicts 10 top IT trend during the next year, and these predictions affect IT and industry leaders and organization's basic assumptions about technology and the future of IT, but the accuracy of these reports are difficult to verify. Social media data can be useful tool to verify the accuracy. As social media services have gained in popularity, it is used in a variety of ways, from posting about personal daily life to keeping up to date with news and trends. In the recent years, rates of social media activity in Korea have reached unprecedented levels. Hundreds of millions of users now participate in online social networks and communicate with colleague and friends their opinions and thoughts. In particular, Twitter is currently the major micro blog service, it has an important function named 'tweets' which is to report their current thoughts and actions, comments on news and engage in discussions. For an analysis on IT trends, we chose Tweet data because not only it produces massive unstructured textual data in real time but also it serves as an influential channel for opinion leading on technology. Previous studies found that the tweet data provides useful information and detects the trend of society effectively, these studies also identifies that Twitter can track the issue faster than the other media, newspapers. Therefore, this study investigates how frequently the predicted IT trends for the following year announced by public organizations are mentioned on social network services like Twitter. IT trend predictions for 2013, announced near the end of 2012 from two domestic organizations, the National IT Industry Promotion Agency (NIPA) and the National Information Society Agency (NIA), were used as a basis for this research. The present study analyzes the Twitter data generated from Seoul (Korea) compared with the predictions of the two organizations to analyze the differences. Thus, Twitter data analysis requires various natural language processing techniques, including the removal of stop words, and noun extraction for processing various unrefined forms of unstructured data. To overcome these challenges, we used SAS IRS (Information Retrieval Studio) developed by SAS to capture the trend in real-time processing big stream datasets of Twitter. The system offers a framework for crawling, normalizing, analyzing, indexing and searching tweet data. As a result, we have crawled the entire Twitter sphere in Seoul area and obtained 21,589 tweets in 2013 to review how frequently the IT trend topics announced by the two organizations were mentioned by the people in Seoul. The results shows that most IT trend predicted by NIPA and NIA were all frequently mentioned in Twitter except some topics such as 'new types of security threat', 'green IT', 'next generation semiconductor' since these topics non generalized compound words so they can be mentioned in Twitter with other words. To answer whether the IT trend tweets from Korea is related to the following year's IT trends in real world, we compared Twitter's trending topics with those in Nara Market, Korea's online e-Procurement system which is a nationwide web-based procurement system, dealing with whole procurement process of all public organizations in Korea. The correlation analysis show that Tweet frequencies on IT trending topics predicted by NIPA and NIA are significantly correlated with frequencies on IT topics mentioned in project announcements by Nara market in 2012 and 2013. The main contribution of our research can be found in the following aspects: i) the IT topic predictions announced by NIPA and NIA can provide an effective guideline to IT professionals and researchers in Korea who are looking for verified IT topic trends in the following topic, ii) researchers can use Twitter to get some useful ideas to detect and predict dynamic trends of technological and social issues.

Analysis of Fault Signal in Gear Using Higher Order Time Frequency Analysis

  • Lee, Sang-Kwon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.5
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    • pp.268-277
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    • 1999
  • Impulsive acoustic and vibration signals within gear are often induced by impacting of fault tooths in gear. Thus the detection of these impulses can be useful for fault diagnosis. Recently there is an increasing trend towards the use of higher order statistics for fault detection within mechanical systems based on the observation that impulsive signals then to increase the kurtosis values. We show that the fourth order Wigner Moment Spectrum, called the Wigner Trispectrum, has found superior detection performance to second order Wigner distribution for typical impulsive signals in a condition monitoring application. These methods are also applied to data sets measured within an industrial gear box.

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Correlation of Peak Time Shift in Blood Pressure Waveform and PPG Based on Compliance Change Analysis in RLC Windkessel Model

  • Choi, Wonsuk;Cho, Jin-Ho
    • Current Optics and Photonics
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    • v.1 no.5
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    • pp.529-537
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    • 2017
  • We explored how changes in blood vessel compliance affected the systolic rise time (SRT) of the maximum blood pressure (BP) peak wave and the diastolic fall time (DFT) of the minimal BP peak wave, compared to photoplethysmograpic (PPG) parameters, using a two-compartment, second-order, arterial Windkessel model. We employed earlier two-compartment Windkessel models and the components thereof to construct equivalent blood vessel circuits, and reproduced BP waveforms using PSpice technology. The SRT and DFT values were obtained via circuit simulation, considering variations in compliance (the dominant influence on blood vessel parameters attributable to BP changes). And then performed regression analysis to identify how compliance affected the SRT and DFT. We compared the SRTs and DFTs of BP waves to the PPG values by reference to BP changes in each subject. We confirmed that the time-shift propensities of BP waves and the PPG data were highly consistent. However, the time shifts differed significantly among subjects. These simulation and experimental results allowed us to construct an initial trend curve of individual BP peak time (measured via wrist PPG evaluations at three arm positions) that facilitated accurate individual BP estimations.

Socio-Cultural Meanings of the Trend of Collaboration Expressed in Contemporary Fashion (현대 패션에 나타난 콜래보레이션(Collaboration) 경향의 사회문화적 의미)

  • Yang, Hee-Young
    • The Research Journal of the Costume Culture
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    • v.18 no.2
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    • pp.245-260
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    • 2010
  • Collaboration among various fields appear according to rising of snack culture, polarizing phenomenon by a point to value, consumer behavior change giving importance to direct experience, and arrival of high touch age satisfied various needs and desires of consumer. Collaboration progressed limited edition form utilizes famous artist and designer's fame to promote products and upgrade their brand image through a short period agreement. This research aims at analysis about collaboration phenomenon in collaboration manners and characteristics, and understands changed socio-cultural meaning through collaboration expressed in almost all industry for high speedy changing fashion environment. This research utilizes between theoretical study and empirical analysis. For concentrated study, research period limits from 2007 to the present time 2009. This paper's purpose is studying on the socio-cultural meaning through analysis about characteristics of the trend of collaboration expressed in contemporary fashion. This research's results are as follow as; First, common life toward aesthetic surrounding, Second, introduction of high concept, Third, the power of Homo Consmus, Forth, focusing on the intangible elements and the value. This study intends to predict change of fashion design and fashion market for complicated consumer, and present fundamental materials about fashion industry and design development of the future through consideration on concrete aspect and meaning of collaboration expressed in contemporary fashion.

Diabetes Mellitus prevalence and related factors in Korean Adult over 19 years according to time trend: Data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2011, 2021

  • Ji-Suk Seong
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.8
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    • pp.123-131
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    • 2024
  • The purpose of this study is to identify the prevalence of diabetes and related factors and thereby to provide fundamental data for the prevention and management of diabetes. This study is a secondary analysis based on the raw data from the Korea National Health and Nutrition Examination Survey (KNHANES) for the years 2011 and 2021. Analysis method was frequency analysis, complex samples Chi-square test, complex samples logistic regression analysis. As a result of the study, the factors related to diabetes were sex, age, education level, hypertension, dyslipidemia, and subjective health recognition in 2011(Negelkerke R2=.255), and sex, age, education level, hypertension, dyslipidemia, mother's diabetes, and subjective health recognition in 2021(Negelkerke R2=.327). This study is meaningful in that the factors related to diabetes were identified according to time trend, and the changes in the related factors were confirmed. Development and application of an intervention program to prevent diabetes are necessary.