• Title/Summary/Keyword: time-dependency

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A Refinement of Point Forecast Using Dependency Structure in Irregualr Component of BOK-X12-ARIMA

  • Hwang, S.Y.;Yang, S.K.
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.1
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    • pp.141-147
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    • 2006
  • BOK-X12-ARIMA has been developed by the Bank of Korea in order to accomodate special features such as lunar effect, labor day and election effect which are intrinsic in Korean seasonal time series. Irregular component resulting from BOK-X12-ARIMA is usually treated as white noise time series. If this shows dependency structure, it may be advisable to incorporate dependency in irregular component into prediction. This article illustrates how to refine point forecast using dependency structure in irregular component.

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Dependence of Quiet Time Geomagnetic Activity Seasonal Variation on the Solar Magnetic Polarity

  • Oh, Suyeon
    • Journal of Astronomy and Space Sciences
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    • v.30 no.1
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    • pp.43-48
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    • 2013
  • The geomagnetic activity shows the semiannual variation stronger in vernal and autumnal equinoxes than in summer and winter solstices. The semiannual variation has been explained by three main hypotheses such as Axial hypothesis, Equinoctial hypothesis, and Russell-McPherron Effect. Many studies using the various geomagnetic indices have done to support three main hypotheses. In recent, Oh & Yi (2011) examined the solar magnetic polarity dependency of the geomagnetic storm occurrence defined by Dst index. They reported that there is no dependency of the semiannual variation on the sign of the solar polar fields. This study examines the solar magnetic polarity dependency of quiet time geomagnetic activity. Using Dxt index (Karinen & Mursula 2005) and Dcx index (Mursula & Karinen 2005) which are recently suggested, in addition to Dst index, we analyze the data of three-year at each solar minimum for eight solar cycles since 1932. As a result, the geomagnetic activity is stronger in the period that the solar magnetic polarity is anti-parallel with the Earth's magnetic polarity. There exists the difference between vernal and autumnal equinoxes regarding the solar magnetic polarity dependency. However, the difference is not statistically significant. Thus, we conclude that there is no solar magnetic polarity dependency of the semiannual variation for quiet time geomagnetic activity.

Mobile Phone Dependency, Motivations and Effects of Mobile Phone Usage Among Korean Adolescents (청소년의 휴대전화 의존, 이용동기 및 결과에 관한 연구)

  • Sung, Yun Sook
    • Korean Journal of Child Studies
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    • v.29 no.4
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    • pp.181-197
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    • 2008
  • A mobile phone usage survey was administered to a nationwide sample of 3,617 adolescents. Major motivations of mobile phone usage were mobility/real-time connection, show off, information acquisition, entertainment, dialogue, schedule management, and advice. Maintenance of social relationship with the peer group was most important in mobile phone use. Motivations influenced mobile phone dependency : show off had the strongest influence on anxiety/paranoia followed by dialogue, entertainment, mobility/real-time connection. Without their phones, fashion-oriented adolescents showed mobile phone dependency and anxiety. Stronger dialogue and entertainment motivations were associated with weaker real time connection motivation and stronger paranoia symptoms. Mobile phone dependent adolescents had lower grades, showed lack of attention, had little dialogue with their parents and showed withdrawal from the peer group.

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Korean Dependency Parsing using Pointer Networks (포인터 네트워크를 이용한 한국어 의존 구문 분석)

  • Park, Cheoneum;Lee, Changki
    • Journal of KIISE
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    • v.44 no.8
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    • pp.822-831
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    • 2017
  • In this paper, we propose a Korean dependency parsing model using multi-task learning based pointer networks. Multi-task learning is a method that can be used to improve the performance by learning two or more problems at the same time. In this paper, we perform dependency parsing by using pointer networks based on this method and simultaneously obtaining the dependency relation and dependency label information of the words. We define five input criteria to perform pointer networks based on multi-task learning of morpheme in dependency parsing of a word. We apply a fine-tuning method to further improve the performance of the dependency parsing proposed in this paper. The results of our experiment show that the proposed model has better UAS 91.79% and LAS 89.48% than conventional Korean dependency parsing.

Associations between Elementary School Students' Cell Phone Dependency and Aggression: The Mediating Effects of Diverse Leisure Activities (초등학생의 휴대전화 의존도와 공격성 간의 관계: 다양한 여가시간의 매개효과)

  • Kim, Hee-Sook;You, Jun Ok;Jung, Changsuk;Hyung, Nakyum
    • Journal of Korean Academy of Psychiatric and Mental Health Nursing
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    • v.27 no.4
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    • pp.406-414
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    • 2018
  • Purpose: The purpose of this study was to investigate the relationship between cell phone dependency and aggression in elementary school students with the mediating effect of leisure activities in South Korea. Methods: Data were cross-sectional in study design with 1,555 fourth grade elementary school students participating in the 4th-year Korean Children and Youth Panel Survey. Data analysis was performed using the SPSS/WIN 23.0 and AMOS 21.0 program. Results: Cell phone dependency has a significant effect on aggression, but it did not act as a control variable in the relationship between the protective factor, weekly book reading time and the amount of daytime play with aggression. Weekly entertainment time and weekly TV and video viewing time had a significant statistical effect on aggression, thus this study confirmed that cell phone dependency acts as a control variable in relation to aggression. Conclusion: As the entertainment time for elementary school students, the time spent watching TV and videos play a negative role, it is necessary to prepare a leisure activity management practice and strategies with an emphasis on entertainment time as well as, TV and video viewing as elementary school students' leisure activities for a healthy school life.

A Data Dependency Elimination Algorithm for Extracting Maximum Parallelism (최대 병렬성 추출을 위한 자료 종속성 제거 알고리즘)

  • 송월봉;박두순
    • Journal of KIISE:Software and Applications
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    • v.26 no.1
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    • pp.139-139
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    • 1999
  • In most application programs, loops usually comprise most of the computation in a program and the most important source of parallelism. When the data dependency relation is uniformin terms of distance, several compile time parallelization methods were introduced. On the otherhand,when the data dependency relation is non-uniform in distance, the compile time extraction ofparallelism is much complicated. In this paper, a general method the extracting parallelism in nestedloops is presented. This algorithm can be applicable where the dependency relation is both uniform andnon-uniform in distance. According to execution repeatedly the statements in nested loops, thealgorithm which effectively removes these kind of data dependencies is developed in order to presentthe total parallelization of nested loops.

SOA Vulnerability Evaluation using Run-Time Dependency Measurement (실행시간 의존성 측정을 통한 SOA 취약성 평가)

  • Kim, Yu-Kyong;Doh, Kyung-Goo
    • The Journal of Society for e-Business Studies
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    • v.16 no.2
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    • pp.129-142
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    • 2011
  • Traditionally research in Service Oriented Architecture(SOA) security has focused primarily on exploiting standards and solutions separately. There exists no unified methodology for SOA security to manage risks at the enterprise level. It needs to analyze preliminarily security threats and to manage enterprise risks by identifying vulnerabilities of SOA. In this paper, we propose a metric-based vulnerability assessment method using dynamic properties of services in SOA. The method is to assess vulnerability at the architecture level as well as the service level by measuring run-time dependency between services. The run-time dependency between services is an important characteristic to understand which services are affected by a vulnerable service. All services which directly or indirectly depend on the vulnerable service are exposed to the risk. Thus run-time dependency is a good indicator of vulnerability of SOA.

Types of Cyberspace Addiction and Adolescents' Psycho-Social Environment (사이버공간 중독유형와 청소년의 사회심리적 환경)

  • 백승문;황미영;김영희
    • Journal of the Korean Home Economics Association
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    • v.41 no.1
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    • pp.169-185
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    • 2003
  • The present study was to investigate whether Cyberspace addiction groups could be classified into types and examine the relationship with types of Cyberspace addiction and adolescents' psychological environment. The findings were as follows: First, adolescents' Cyberspace addiction was analyzed by factor analysis and classified by four different types, which were named as sensation seeking, life interference, time dependency, and psychological dependency. Second, male students experienced more sensation seeking and life interference tendencies than female students who experienced more psychological dependency tendency than male students. High school students experienced more life interference tendency than middle school students. Third, there was relationship with types of adolescents Cyberspace addiction and psychological environment. Adolescents who addicted Cyberspace with sensation seeking were more likely to avoid conversation with families, and had a tendency of compulsiveness and depression. Adolescents who addicted Cyberspace with life interference had a tendency of compulsiveness and depression, and had a problem of school life and family relationship. Adolescents who addicted Cyberspace with time dependency showed the compulsiveness and avoided conversation with families. Adolescents who addicted Cyberspace with psychological dependency were more likely to have peer relationship and had a tendency of depression. Conclusively, the psycho-social environment such as compulsiveness, depression, family and peer relationship, and school environment was related to types of adolescents' Cyberspace addiction more or less.

Aggregate-level Analysis of Auto Travel Dependency on Freeways in the Seoul Metropolitan Area (집계자료를 이용한 수도권내 승용차 통행의 고속도로 의존도 분석)

  • Go, Jun-Ho;Lee, Seong-Hun
    • Journal of Korean Society of Transportation
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    • v.29 no.6
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    • pp.7-16
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    • 2011
  • This study investigates the degree of dependency on freeways when auto travelers make route choices in the Seoul Metropolitan Area. The investigation is conducted based on aggregated auto trip data, defining the degree of dependency as the proportion of auto trips selecting freeways in their travel paths. The analyses reveal that the trips departing from the areas with higher accessibility to freeways tend to exhibit higher dependency on freeways. In addition, the dependency is significantly affected by the travel time differences between two paths including and excluding freeways, respectively. The number of service interchanges was found to be one of significant factors for trips to Incheon and Gyenggi areas. The finding indicates that the factors affecting the degree of dependency on freeways may vary depending on the areas' characteristics. The findings would enhance the understanding of drivers' route choice behavior in Seoul at an aggregate level.

Semi-Automatic Annotation Tool to Build Large Dependency Tree-Tagged Corpus

  • Park, Eun-Jin;Kim, Jae-Hoon;Kim, Chang-Hyun;Kim, Young-Kill
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.385-393
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    • 2007
  • Corpora annotated with lots of linguistic information are required to develop robust and statistical natural language processing systems. Building such corpora, however, is an expensive, labor-intensive, and time-consuming work. To help the work, we design and implement an annotation tool for establishing a Korean dependency tree-tagged corpus. Compared with other annotation tools, our tool is characterized by the following features: independence of applications, localization of errors, powerful error checking, instant annotated information sharing, user-friendly. Using our tool, we have annotated 100,904 Korean sentences with dependency structures. The number of annotators is 33, the average annotation time is about 4 minutes per sentence, and the total period of the annotation is 5 months. We are confident that we can have accurate and consistent annotations as well as reduced labor and time.

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