• Title/Summary/Keyword: Correlation Network

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Predicting the Popularity of Post Articles with Virtual Temperature in Web Bulletin (웹게시판에서 가상온도를 이용한 게시글의 인기 예측)

  • Kim, Su-Do;Kim, So-Ra;Cho, Hwan-Gue
    • The Journal of the Korea Contents Association
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    • v.11 no.10
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    • pp.19-29
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    • 2011
  • A Blog provides commentary, news, or content on a particular subject. The important part of many blogs is interactive format. Sometimes, there is a heated debate on a topic and any article becomes a political or sociological issue. In this paper, we proposed a method to predict the popularity of an article in advance. First, we used hit count as a factor to predict the popularity of an article. We defined the saturation point and derived a model to predict the hit count of the saturation point by a correlation coefficient of the early hit count and hit count of the saturation point. Finally, we predicted the virtual temperature of an article using 4 types(explosive, hot, warm, cold). We can predict the virtual temperature of Internet discussion articles using the hit count of the saturation point with more than 70% accuracy, exploiting only the first 30 minutes' hit count. In the hot, warm, and cold categories, we can predict more than 86% accuracy from 30 minutes' hit count and more than 90% accuracy from 70 minutes' hit count.

The relationship among SNS addiction, Depression and Communication skill of nursing students (간호대학생의 SNS 중독경향성, 우울과 의사소통능력간의 관계)

  • Kwon, Myoungjin;Kim, Jihyun;Jung, Sunkyung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.405-413
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    • 2018
  • The purpose of this study was to investigate the influence of SNS addiction tendency, depression, and communication skill among university students. Subjects were 200 associate nursing students in Korea. The data were collected using a self-reporting questionnaire from October 11 to November 24, 2016. Data were analyzed by descriptive statistics, t-test, ANOVA, LSD test, Pearson's correlation coefficients, and multiple regression analysis using the SPSS/WIN 23.0 program. The levels of SNS addiction tendency were dependent on age (t=2.47, p=.044), connection SNS time (F=10.20, p<.001), and place of SNS use (t=2.54, p=.012). SNS addiction tendency was significantly correlated with depression. Higher SNS addiction was associated with higher rates of depression. SNS addiction tendency was not significantly correlated with communication skill in nursing students. Influential factors that affect SNS addiction tendency were depression (${\beta}=.265$, p<.001) and SNS usage time (${\beta}=.265$, p<.001), which explains about 15.5% of the variance. The results of this study indicate that nursing interventions are necessary to improve SNS addiction tendency, and early screening of nursing students is needed to develop health promotion programs for the vulnerable.

Analysis on Spatial Variability of Rainfall in a Small Area (소규모 지역에 대한 강우의 공간변화도 분석)

  • Kim, Jong Pil;Kim, Won;Kim, Dong-Gu;Lee, Chanjoo
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.905-913
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    • 2015
  • This study deployed six rain gauges in a small area for a dense network observing rainfall and analyzed the spatial variability of rainfall. They were arranged in a $2{\times}3$ rectangular grid with equal space of 60 m. The rainfall measurements from five gauges were analyzed during the period of 50 days because one was seriously affected by alien substance. The maximum difference in cumulative rainfall from them is approximately 38.5 mm. The correlation coefficients from hourly rainfall time series differ from each other while daily rainfall coincide. The coefficient of variation in hourly rainfall varies up to 224% and that in daily rainfall up to 91%. The results from uncertainty analysis show that with only four rain gauges areal mean rainfall cannot be estimated over 95% accuracy. For reliable flood prediction and effective water management it is required to develop a new technique for the estimation of areal rainfall.

A Study on the Relation between IRI and PrI (평탄성 지수 IRI와 PrI의 상관관계에 관한 연구)

  • Kim, Kook-Han;Lee, Byung-Duck;Choi, Go-Il;Yang, Sung-Cheol
    • International Journal of Highway Engineering
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    • v.5 no.1 s.15
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    • pp.11-18
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    • 2003
  • Road roughness, as the key factor influencing not only drivers' ride quality and safety but also pavement deterioration, is one of the most important pavement performance indicator to be evaluated by users' subjective assessment. For this reason, a specific number of the pavement roughness has been adopted to monitor the condition of a road for pavement management systems and to evaluate the quality of newly constructed sections, however, none of the unified methodology was internationally accepted. In Korea highway network, road roughness has been used mainly to evaluate newly placed pavement by using 7.6m CP (California Profile meter) to calculate PrI (Profile Index). But this instrument is manually operated to measure road profiles by traffic closure and their interpretation depends on personal bias. Therefore, problems arisen from the manually operated instrument will be overcome by using the APL (Longitudinal Profile Analyzer) which can be operated in the speed of 80km per hour. A study was conducted to correlate the relation from both concrete and asphalt pavement between IRI (measured by APL) and PrI (measured by 7.6m CP). Test results showed that there was a good correlation between IRI and PrI.

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Development of Computation Model for Traffic Accidents Risk Index - Focusing on Intersection in Chuncheon City - (교통사고 위험도 지수 산정 모델 개발 - 춘천시 교차로를 중심으로 -)

  • Shim, Kywan-Bho;Hwang, Kyung-Soo
    • International Journal of Highway Engineering
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    • v.11 no.3
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    • pp.61-74
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    • 2009
  • Traffic accident risk index Computation model's development apply traffic level of significance about area of road user group, road and street network area, population group etc.. through numerical formula or model by countermeasure to reduce the occurrence rate of traffic accidents. Is real condition that is taking advantage of risk by tangent section through estimation model and by method to choose improvement way to intersection from outside the country, and is utilizing being applied in part business in domestic. However, question is brought in the accuracy being utilizing changing some to take external model in domestic real condition than individual development of model. Therefore, selection intersection estimation element through traffic accidents occurrence present condition, geometry structure, control way, traffic volume, turning traffic volume etc. in 96 intersections in this research, and select final variable through correlation analysis of abstracted estimation elements. Developed intersection design model taking advantage of signal type, numeric of lane, intersection type, analysis of variance techniques through ANOVA analysis of three variables of intersection form with selected variable lastly, in signal crossing through three class intersection, distinction variable choice risk in model, no-signal crossing risk distinction analysis model and so on develop.

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Effects of Zoning Structure on Travel Demand Forecasts (존 체계 구축이 교통수요 추정에 미치는 영향에 관한 연구)

  • Han, Myeong-Ju;Seong, Hong-Mo;Baek, Seung-Han;Im, Yong-Taek;Lee, Yeong-In
    • Journal of Korean Society of Transportation
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    • v.29 no.1
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    • pp.17-27
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    • 2011
  • This paper investigates some critical errors influencing travel demand estimation in Korea Transportation Data Base (KTDB), and through this investigation reasonable traffic analysis zone (TAZ) size and internal trips ratio are analyzed. With varying zone size, the accuracy of travel demand estimation is studied and appropriate level of zone size in KTDB is also presented. For this purpose zonal structure consisting of location of zone centroid, number of centroid connecters has been constructed by social economic index, and then some descriptive statistical analyses such as F-test, coefficient of correlation are performed. From the results, this paper shows that the optimum levels of zone system were various according to the order and capacity of roads, and also shows that the smaller TAZ, the less error in this research. In conclusion, in order to improve accuracy of traffic demand estimation it is necessary to make zone size smaller.

Stability Assessment of FKP System by NGII using Long-term Analysis of NTRIP Correction Signal (NTRIP 보정신호 분석을 통한 국토지리정보원 FKP NRTK 시스템 안정성 평가)

  • Kim, Min-Ho;Bae, Tae-Suk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.4
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    • pp.321-329
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    • 2013
  • Despite the advantage of unlimited access, there are insufficient studies for the accuracy and stability of FKP that blocks the spread of the system for various applications. Therefore, we performed a long-term analysis from continuous real-time positioning, and investigated the error characteristics dependent on the size and the surrounding environment. The FKP shows significant changes in the positioning accuracy at different times of day, where the accuracy during daytime is worse than that of nighttime. In addition, the size and deviation of FKP correction may change with the ionospheric conditions, and high correlation between ambiguity resolution rate and the deviation of correction was observed. The receivers continuously request the correction information in order to cope with sudden variability of ionosphere. On the other hand, the correction information was not received up to an hour in case of stable ionospheric condition. It is noteworthy that the outliers of FKP are clustered in their position with some biases. Since several meters of errors can be occurred for kinematic positioning with FKP, therefore, it is necessary to make appropriate preparation for real-time applications.

Prediction of Wetting and Interfacial Property of CNT Reinforced Epoxy on CF Tow Using Electrical Resistance Method (전기저항 평가법을 이용한 CNT 함유 에폭시의 탄소섬유내 젖음성 및 계면특성 예측 연구)

  • Kwon, Dong-Jun;Choi, Jin-Yeong;Shin, Pyeong-Su;Lee, Hyung-Ik;Lee, Min-Gyeong;Park, Jong-Kyoo;Park, Joung-Man
    • Composites Research
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    • v.28 no.4
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    • pp.232-238
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    • 2015
  • As a new method to predict the degree of dispersion in carbon nanocomposites, the electrical resistance (ER) method has been evaluated. After CNT epoxy resin was dropped on CF tow, the change in electrical resistance of carbon fiber tow was measured to evaluate dispersion condition in CNT epoxy resin. Good dispersion of CNTs in carbon nanocomposite exhibited low change in ER due to wetted resin penetrated on CF tow. However, because CNT network was formed among CFs, non-uniform dispersion occurred due to nanoparticle filtering effect by CF tow. The change in ER for poor dispersion exhibited large ER signal change. The change in ER was used for the dispersion evaluation of CNT epoxy resin. Correlation between interlaminar shear strength (ILSS) and dispersion condition by ER method was established. Good CNT dispersion in nanocomposites led to good interfacial properties of fiberreinforced nanocomposites.

Quality Metric with Video Characteristics on Scalable Video Coding (영상 특성을 고려한 스케일러블 비디오 기반 품질 메트릭)

  • Yoo, Ha-Na;Kim, Cheon-Seog;Lee, Ho-Jun;Jin, Sung-Ho;Ro, Yong-Man
    • Journal of Broadcast Engineering
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    • v.13 no.2
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    • pp.179-187
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    • 2008
  • In this paper, we proposed the qualify metric based on SVC and the subjective quality. The proposed quality metric is for a general purpose. It means we can use it for any video sequences regardless of its temporal and spatial characteristics. The Quality of Service(QoS) is one of the important issues in heterogeneous environment which has diverse restrictions such as limited network bandwidth and limited display resolution. Scalable Video Coding(SVC) is the efficient video coding skill in heterogeneous environment. Because SVC can be adapted to various quality bitstreams using three scalabilities(spatial, temporal, and SNR) from one bitstream which has full scalability. To maximize the QoS in this environment, we should consider the subjective quality which is the viewer response. And also we should consider temporal and spatial characteristics of video sequence because the subjective quality is affected by temporal and spatial characteristics of video sequence. To verify the efficiency of the proposed method, we perform subjective assessments. The experimental results show that the proposed method has high correlation with subjective quality. The proposed method can be a decision tool of SVC birstream extraction.

A study on the correlation between the degree of elasticity uniformity and the dynamic performance in the overhead contact lines (전차선로 탄성도 불균일율과 동역학적 성능과의 관계에 대한 연구)

  • Park, Sa-Hoon;Kwon, Sam-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.502-502
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    • 2007
  • A catenary system should be designed to have an uniform elasticity over a span in order to maintain the lowest possible loss of contact between a pantograph and a contact wire. A elasticity uniformity of a catenary can be regarded as a important design factor used for predicting the current collection performance for a catenary. There are a couple of formulas to calculate the degree of elasticity uniformity of a catenary according to the literature survey. The effectiveness of these formulas is reviewed by performing catenary elasticity and loss of contact analysis for various different configurations of catenary systems using a beam element based FEM program. The results reveals that these formulas are not suitable to predict the current collection performance for a catenary. Therefore, a new formula based on the standard deviation of the elasticity over a span is proposed in this study. The analysis results show that the new formula for an elasticity uniformity of a catenary is very effective in predicting the current collection performance for a catenary.

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