• Title/Summary/Keyword: Time series topic analysis

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Application of Urban Computing to Explore Living Environment Characteristics in Seoul : Integration of S-Dot Sensor and Urban Data

  • Daehwan Kim;Woomin Nam;Keon Chul Park
    • Journal of Internet Computing and Services
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    • v.24 no.4
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    • pp.65-76
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    • 2023
  • This paper identifies the aspects of living environment elements (PM2.5, PM10, Noise) throughout Seoul and the urban characteristics that affect them by utilizing the big data of the S-Dot sensors in Seoul, which has recently become a hot topic. In other words, it proposes a big data based urban computing research methodology and research direction to confirm the relationship between urban characteristics and living environments that directly affect citizens. The temporal range is from 2020 to 2021, which is the available range of time series data for S-Dot sensors, and the spatial range is throughout Seoul by 500mX500m GRID. First of all, as part of analyzing specific living environment patterns, simple trends through EDA are identified, and cluster analysis is conducted based on the trends. After that, in order to derive specific urban planning factors of each cluster, basic statistical analysis such as ANOVA, OLS and MNL analysis were conducted to confirm more specific characteristics. As a result of this study, cluster patterns of environment elements(PM2.5, PM10, Noise) and urban factors that affect them are identified, and there are areas with relatively high or low long-term living environment values compared to other regions. The results of this study are believed to be a reference for urban planning management measures for vulnerable areas of living environment, and it is expected to be an exploratory study that can provide directions to urban computing field, especially related to environmental data in the future.

Trends of South Korea's Informatization and Libraries' Role Based on Newspaper Big Data (신문 빅데이터를 바탕으로 본 국내 정보화의 경향과 도서관의 역할)

  • Na, Kyoungsik;Lee, Jisu
    • The Journal of the Korea Contents Association
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    • v.18 no.9
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    • pp.14-33
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    • 2018
  • The purpose of this study to analyze the informatization trends in Korea through objective newspaper data for the period from 1998 to 2017 for informatization and library in four newspapers including KyoungHyang Newspaper, Kookmin Ilbo, Hankyoreh and Hankookilbo. Based on the analysis results of metadata and related words using BIGKinds, a news big data system, this study presented analysis of simple frequency, classification and classification of the keywords 'information', 'informatization' and 'library'. Based on the results, we compared and analyzed the tendency of informatization in the media through comparison with the 'Information White Paper' which is the publication of government agencies and with research about the research topic of 4 academic journals in the Library and Information Science field. This study tried to interpret the trends of informatization based on the media and it is meaningful that we analyzed the big data of newspaper article which is the long term and time series data. Based on the results of the study, implications of the growth and development of libraries with domestic informatization were suggested. It is expected that we will be able to create a basic framework for developing library informatization policy through the further studies.

A Study on the Deduction of Social Issues Applying Word Embedding: With an Empasis on News Articles related to the Disables (단어 임베딩(Word Embedding) 기법을 적용한 키워드 중심의 사회적 이슈 도출 연구: 장애인 관련 뉴스 기사를 중심으로)

  • Choi, Garam;Choi, Sung-Pil
    • Journal of the Korean Society for information Management
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    • v.35 no.1
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    • pp.231-250
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    • 2018
  • In this paper, we propose a new methodology for extracting and formalizing subjective topics at a specific time using a set of keywords extracted automatically from online news articles. To do this, we first extracted a set of keywords by applying TF-IDF methods selected by a series of comparative experiments on various statistical weighting schemes that can measure the importance of individual words in a large set of texts. In order to effectively calculate the semantic relation between extracted keywords, a set of word embedding vectors was constructed by using about 1,000,000 news articles collected separately. Individual keywords extracted were quantified in the form of numerical vectors and clustered by K-means algorithm. As a result of qualitative in-depth analysis of each keyword cluster finally obtained, we witnessed that most of the clusters were evaluated as appropriate topics with sufficient semantic concentration for us to easily assign labels to them.

Analysis of Spatial Growth Characteristics of Major Cities in Hunan Province, China for Sustainable Urban Management (지속 가능한 도시경영을 위한 중국 후난성 주요 도시의 공간적 성장 특징분석)

  • Yang, Li-jun;Kim, Hyunchul;Ahn, Chulok
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.45 no.3
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    • pp.197-203
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    • 2022
  • Urban space expansion is an important symbol of the urbanization process and has always been an important topic in urban studies. In addition, for sustainable city management, it is important to identify factors that can influence, such as the driving force and direction of urban space expansion, from the stage of establishing an urban development plan. To understand these factors, by observing the expansion process of a specific city, it is possible to sufficiently observe how the urban spatial dimension changes. Through a series of processes, the spatial growth characteristics of the city are analyzed, and the influence and results of important factors are analyzed. For this purpose, this paper examines the changes in the city's outer boundary and land use structure through monitoring data on urban areas of 14 cities in Hunan Province, China from 2000 to 2016. Temporal and spatial regularity according to the urban space expansion of these cities were analyzed, and a preliminary assessment was made on whether the urban space expansion is coordinated with the urban population growth. The assessment result showed: (1) The urban space of most cities has been extended rapidly in 2000-2015 however, the rate and the intensity of urban space expanding has been declining. (2) The construction of the industrial park is the core driving force of the urban space expanding, and the change of the urban space structure is manifested as enclave city expansion because that the industrial park is usually far away from the city center. (3) The population agglomeration is another driving force of the urban space expanding. At this time, the urban space expanding is like boundary extension. (4) Except Changsha city, all of the cities has a high urbanization-area-growth elastic coefficient. It means that most of the cities should enhance the land use degree.

Short-term Effect of Fine Particulate Matter on Children's Hospital Admissions and Emergency Department Visits for Asthma: A Systematic Review and Meta-analysis

  • Lim, Hyungryul;Kwon, Ho-Jang;Lim, Ji-Ae;Choi, Jong Hyuk;Ha, Mina;Hwang, Seung-sik;Choi, Won-Jun
    • Journal of Preventive Medicine and Public Health
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    • v.49 no.4
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    • pp.205-219
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    • 2016
  • Objectives: No children-specified review and meta-analysis paper about the short-term effect of fine particulate matter ($PM_{2.5}$) on hospital admissions and emergency department visits for asthma has been published. We calculated more precise pooled effect estimates on this topic and evaluated the variation in effect size according to the differences in study characteristics not considered in previous studies. Methods: Two authors each independently searched PubMed and EMBASE for relevant studies in March, 2016. We conducted random effect meta-analyses and mixed-effect meta-regression analyses using retrieved summary effect estimates and 95% confidence intervals (CIs) and some characteristics of selected studies. The Egger's test and funnel plot were used to check publication bias. All analyses were done using R version 3.1.3. Results: We ultimately retrieved 26 time-series and case-crossover design studies about the short-term effect of $PM_{2.5}$ on children's hospital admissions and emergency department visits for asthma. In the primary meta-analysis, children's hospital admissions and emergency department visits for asthma were positively associated with a short-term $10{\mu}g/m^3$ increase in $PM_{2.5}$ (relative risk, 1.048; 95% CI, 1.028 to 1.067; $I^2=95.7%$). We also found different effect coefficients by region; the value in Asia was estimated to be lower than in North America or Europe. Conclusions: We strengthened the evidence on the short-term effect of $PM_{2.5}$ on children's hospital admissions and emergency department visits for asthma. Further studies from other regions outside North America and Europe regions are needed for more generalizable evidence.

An Informetric Analysis on the Notation of East Sea Recorded in Academic Journals ('동해' 표기에 대한 계량적 분석)

  • Han, Jong Yup
    • Journal of the Korean Society for information Management
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    • v.32 no.1
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    • pp.23-41
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    • 2015
  • This study worked on the qualitative analysis about nomenclature East Sea by the record type in researches related to East Sea shown in the scientific journals. Here in this study, the way of marking is classified as three: 'sole notation of East Sea', 'sole notation of Sea of Japan', and 'simultaneous notation of both'. Based on a total of 4,192 selections from Web of Science DB, the analysis was followed up for change in time series by the notation type, notation type according to the nation that authors belong to, difference in research topic, impact factor, collaboration in research, and co-authorship network. The result turned out in this work that the sole notation of Sea of Japan accounted for the largest portion. It also showed that the rates of sole notation of East Sea and simultaneous notation have kept increasing continuously since the 1990s. Hub nations regarding the research of East Sea is five including Japan, Russia, Korea, USA, and China. In the case of sole notation of Sea of Japan, active collaboration studies are performed in USA, Russia, and China with a focus in Japan. In the case of sole notation of East Sea and simultaneous use, the research rate is relatively high in USA and Japan with a focus in Korea. As to the co-authorship network in the sole notation of Sea of Japan, sort of a "giant component" among different groups has been set up and through which the collaborative works are actively underway. However, it was found that the research of sole notation of East Sea is dispersed into small groups on the base of relevant individual institution.

Comparison on Patterns of Conflicts in the South China Sea and the East China Sea through Analysis on Mechanism of Chinese Gray Zone Strategy (중국의 회색지대전략 메커니즘 분석을 통한 남중국해 및 동중국해 분쟁 양상 비교: 시계열 데이터에 근거한 경험적 연구를 중심으로)

  • Cho, Yongsu
    • Maritime Security
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    • v.1 no.1
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    • pp.273-310
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    • 2020
  • This study aims at empirically analyzing the overall mechanism of the "Gray Zone Strategy", which has begun to be used as one of Chinese major maritime security strategies in maritime conflicts surrounding the South China Sea and East China Sea since early 2010, and comparing the resulting conflict patterns in those reg ions. To this end, I made the following two hypotheses about Chinese gray zone strategy. The hypotheses that I have argued in this study are the first, "The marine gray zone strategy used by China shows different structures of implementation in the South China Sea and the East China Sea, which are major conflict areas.", the second, "Therefore, the patterns of disputes in the South China Sea and the East China Sea also show a difference." In order to examine this, I will classify Chinese gray zone strategy mechanisms multi-dimensionally in large order, 1) conflict trends and frequency of strategy execution, 2) types and strengths of strategy, 3) actors of strategy execution, and 4) response methods of counterparts. So, I tried to collect data related to this based on quantitative modeling to test these. After that, about 10 years of data pertaining to this topic were processed, and a research model was designed with a new categorization and operational definition of gray zone strategies. Based on this, I was able to successfully test all the hypotheses by successfully comparing the comprehensive mechanisms of the gray zone strategy used by China and the conflict patterns between the South China Sea and the East China Sea. In the conclusion, the verified results were rementioned with emphasizing the need to overcome the security vulnerabilities in East Asia that could be caused by China's marine gray zone strategy. This study, which has never been attempted so far, is of great significance in that it clarified the intrinsic structure in which China's gray zone strategy was implemented using empirical case studies, and the correlation between this and maritime conflict patterns was investigated.

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