• Title/Summary/Keyword: 평균분산모형

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Long-gap Filling Method for the Coastal Monitoring Data (해양모니터링 자료의 장기결측 보충 기법)

  • Cho, Hong-Yeon;Lee, Gi-Seop;Lee, Uk-Jae
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.6
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    • pp.333-344
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    • 2021
  • Technique for the long-gap filling that occur frequently in ocean monitoring data is developed. The method estimates the unknown values of the long-gap by the summation of the estimated trend and selected residual components of the given missing intervals. The method was used to impute the data of the long-term missing interval of about 1 month, such as temperature and water temperature of the Ulleungdo ocean buoy data. The imputed data showed differences depending on the monitoring parameters, but it was found that the variation pattern was appropriately reproduced. Although this method causes bias and variance errors due to trend and residual components estimation, it was found that the bias error of statistical measure estimation due to long-term missing is greatly reduced. The mean, and the 90% confidence intervals of the gap-filling model's RMS errors are 0.93 and 0.35~1.95, respectively.

The Influence of Strengths Knowledge and Nursing Professionalism on Career Identity in Nursing Students (간호대학생의 강점인식과 간호전문직관이 진로정체감에 미치는 영향)

  • kim, Kyoung-Ha
    • Journal of the Korea Convergence Society
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    • v.13 no.3
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    • pp.363-370
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    • 2022
  • This study was execute to find out the influence of strengths knowledge and nursing professionalism on career identity in nursing students. Data were collected from nursing students attending in the nursing departments in G and M cities from July to September 2021. Among the collected data, 198 data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and controlled regression analysis. As a result of data analysis, strengths knowledge(β=.473, p<.001) and nursing professionalism(β=.167, p<.01) reported to have effect on career identity. The study model accounted for 48.2% of career identity. These findings suggest that program to improve strengths knowledge and nursing professionalism should be developed and operated to promote career identity of nursing students in the nursing education field.

A Study on Estimating Rice Yield in DPRK Using MODIS NDVI and Rainfall Data (MODIS NDVI와 강수량 자료를 이용한 북한의 벼 수량 추정 연구)

  • Hong, Suk Young;Na, Sang-Il;Lee, Kyung-Do;Kim, Yong-Seok;Baek, Shin-Chul
    • Korean Journal of Remote Sensing
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    • v.31 no.5
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    • pp.441-448
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    • 2015
  • Lack of agricultural information for food supply and demand in Democratic People's republic Korea(DPRK) make people sometimes confused for right and timely decision for policy support. We carried out a study to estimate paddy rice yield in DPRK using MODIS NDVI reflecting rice growth and climate data. Mean of MODIS $NDVI_{max}$ in paddy rice over the country acquired and processed from 2002 to 2014 and accumulated rainfall collected from 27 weather stations in September from 2002 to 2014 were used to estimated paddy rice yield in DPRK. Coefficient of determination of the multiple regression model was 0.44 and Root Mean Square Error(RMSE) was 0.27 ton/ha. Two-way analysis of variance resulted in 3.0983 of F ratio and 0.1008 of p value. Estimated milled rice yield showed the lowest value as 2.71 ton/ha in 2007, which was consistent with RDA rice yield statistics and the highest value as 3.54 ton/ha in 2006, which was not consistent with the statistics. Scatter plot of estimated rice yield and the rice yield statistics implied that estimated rice yield was higher when the rice yield statistics was less than 3.3 ton/ha and lower when the rice yield statistics was greater than 3.3 ton/ha. Limitation of rice yield model was due to lower quality of climate and statistics data, possible cloud contamination of time-series NDVI data, and crop mask for rice paddy, and coarse spatial resolution of MODIS satellite data. Selection of representative areas for paddy rice consisting of homogeneous pixels and utilization of satellite-based weather information can improve the input parameters for rice yield model in DPRK in the future.

The effect of screw tightening techniques on the detorque value in internal connection implant superstructure (내부연결 임플란트 상부구조물에서 나사조임술식이 풀림토크값에 미치는 영향)

  • Choi, Jung-Han
    • The Journal of Korean Academy of Prosthodontics
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    • v.48 no.4
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    • pp.243-250
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    • 2010
  • Purpose: This study evaluated the effect of different screw tightening sequences and methods on detorque values in a well-fitting implant superstructure. Materials and methods: A fully edentulous mandibular master model and a metal framework directly connected to four parallel implants (Astra Tech) with a passive fit to each other were fabricated. Six stone casts were made with a splinted impression technique to represent a 'well-fitting' situation with the metal framework. Detorque values were measured twice after screw tightening using 20 Ncm. Detorque values and minimum detorque values for three screw tightening sequences (1-2-3-4, 2-4-3-1, and 2-3-1-4) and for two tightening methods (two-step and one-step) were analyzed using multi-way analysis of variance and two-way analysis of variance, respectively, at a .05 level of significance. Results: The mean detorque values for screw tightening sequences ranged from 12.8 Ncm (2-4-3-1) to 13.1 Ncm (2-3-1-4), and for screw tightening methods were 13.1 Ncm (two-step) and 11.8 Ncm (one-step). The mean of mimimum detorque values for screw tightening sequences were 11.1 Ncm (1-2-3-4) and 11.2 Ncm (2-4-3-1 and 2-3-1-4), and for screw tightening methods were 11.2 Ncm (two-step) and 9.9 Ncm (one-step). No statistically significant differences among three screw tightening sequences were found for detorque values and for mimimum detorque values. But, statistically significant differences between two screw tightening methods were found for two values. Two-step screw tightening method showed higher detorque value (P = .0003) and higher minimum detorque value (P = .0035) than one-step method. Conclusion: Within the limitations of this study, the screw tightening sequence was not a critical factor for the detorque values in a well-fitting implant superstructure by the splinted impression technique. But, two-step screw tightening method showed greater detorque values than one-step method.

Studies on Differentiation of a Paddy Weed, Bur Beggarticks(Bidens tripartita L.) (논 잡초(雜草) 가막사리(Bidens tripartita L.) 생태종(生態種)의 분화(分化)에 관(關)한 연구(硏究))

  • Kim, Myung-Hyun;Rho, Yeong-Deok
    • Korean Journal of Weed Science
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    • v.17 no.3
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    • pp.303-309
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    • 1997
  • Variation of morphological and physiological traits of 50 Bidens tripartita accessions were studied and the accessions were grouped through cluster analysis based on four major characters; plant type, leaf partition, achene length, days to flowering. Bidens tripartite accessions have shown significant variations in plant type, stem length, days to flowering, leaf shape, leaf partition, chlorophyll content, leaf color, stem color, achene color, achene length and achene shape. Most of Bidens tripartite accessions appeared to have strong dormancy and also photodormancy with some exceptions. Plants could be classified into 5 types from straight(I) to triangle(V), and intermediate diamond type(III) was prevalent. The plant type score has negative correlation with the stem length. None, three, and five part leaved plants were observed and most of them were three or five parted. Leaf partition had negative correlation with achene length and chlorophyll content. Average days to flowering was 108 days in the range of 94~141 days. It had positive correlation with achene length and leaf shape and negative correlation with achene color. Average achene length was 10.0mm and it had positive correlation with achene shape, stem length, days to flowering and leaf shape. It also had negative correlation with leaf color, stem color, achene color, leaf partition. Bidens tripartite accessions could be divided into identifiable six groups from the cluster analysis at the distance 0.06 using Ward's minimum-variance method.

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인터넷, 인트라넷과 연계되는 데이타웨어하우스 시스템의 구축방안

  • 박주석;김찬수
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.10a
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    • pp.73-77
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    • 1996
  • 정보는 의사결정자들의 수주에 있을 때 기업에 있어 강력한 경쟁무기가 된다. 의사결정자들의 정보에 대한 이러한 필요성을 충족시키기 위해서 데이타는 운영시스템(Operational System)에서 추출되어 데이타웨어하우스에 저장된다. 데이타웨어하우스는 핵심 비지니스영역(key business dimension)에 의해 정리된 historical data를 저장한다. 이러한 의사결정자들을 위한 데이타웨어하우스 정보의 전달은 기존의 클라이언트/서버 시스템 하에서는 많은 지원을 요구한다. 즉 기존 클라이언트/서버 시스템 하에서는 사용자들의 접근을 위해 데이타가 추출되고 조직화되어지고 나면, 반드시 분석 소프트웨어가 각 사용자의 컴퓨터에 설치되어야 하고 외부의 사용자를 위한 새로운 운영자가 고용되어야 한다. 사용자의 다양한 요구 그리고 계속적 사용자의 교체는 사용자 지원에 있어 심각한 기업부담으로 작용한다. 또한 클라이언트/서버 시스템에서는 기업외부의 정보 이용자들에게 정보를 제공하는데 있어 장소적 한계점을 가지고 잇다. 인트라넷과 인터넷은 이러한 클라이언트/서버 시스템 환경의 문제에 대해 해답을 제시한다. 인트라넷은 데이타웨어하우스로의 접근을 간단히 할뿐만 아니라 의사결정자들의 정보의 공유와 상호분석의 새로운 단계를 제공한다. 그리고 인터넷은 기업 외부 어디에서나 기업이 제공하는 정보를 이용하고자 하는 사람들에게 접근의 편의성을 제공한다. 즉 데이타웨어하우스의 목표와 인트라넷, 인터넷의 목표는 데이타로의 손쉬운 접근이라는 점에서 동일하다. 이러한 점에 착안하여 인트라넷과 인터넷하에서 운용되는 데이타웨어하우스 시스템 구축을 위한 방안을 제시하고자 한다.다(학생군:8.16kg 작업자군:12.9kg). 심박수를 이용한 생리학적 연구에서는 평균 심박수가 거의 100 이하를 유지하므로써 피실험자들이 8시간 작업기준으로 보아 무리가 없는 최대허용 하중을 결정하였음을 보였다. 또한 각 운반작업에 대한 최대허용 하중을 예측하는 회귀모형을 제시하였다.아직 정립되어 있지 않은 분산 환경하에서의 관계형 데이타베이스의 데이타관리의 분류체계를 나름대로 정립하였다는데 그 의의가 있다. 또한 이것의 응용은 현재 분산데이타베이스 구축에 있어 나타나는 기술적인 문제점들을 어느정도 보완할 수 있다는 점에서 그 중요성이 있다.ence of a small(IxEpc),hot(Tex> SOK) core which contains two tempegatlue peaks at -15" east and north of MDS. The column density of HCaN is (1-3):n1014cm-2. Column density at distant position from MD5 is larger than that in the (:entral region. We have deduced that this hot-core has a mass of 10sR1 which i:s about an order of magnitude larger those obtained by previous studies.previous studies.업순서들의 상관관계를 고려하여 보다 개선된 해를 구하기 위한 연구가 요구된다. 또한, 준비작업비용을 발생시키는 작업장의 작업순서결정에 대해서도 연구를 행하여, 보완작업비용과 준비비용을 고려한 GMMAL 작업순서문제를 해

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Recrystallization Topology : a Scale-free Power-law Network (재결정 위상 : 척도 없는 거듭제곱 법칙 망)

  • Park, Jae-Hyun
    • Journal of KIISE:Information Networking
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    • v.37 no.3
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    • pp.167-174
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    • 2010
  • Recently the distributed topology control algorithm for constructing the Recrystallization Topology in the unstructured peer-to-peer network was proposed. In this paper, we prove that such a hierarchical topology is a scale-free power-law network. We present a model of a construction process of the distributed protocol, and analyze it based on a mean-field approximation and the continuum theory, so that we show that the constructed Recrystallization Topology is a scale-free network. In the proposed model, all nodes are born with some initial attractiveness and the system incorporates the rewiring of some links at every time step. Some old links are removed with the anti-preferential probability, and some new links are added with preferential probability. In other words, according to the distributed algorithm, each node makes connections to the more-preferential nodes having higher hit-ratio than other nodes, while it disconnects the anti-preferential nodes having lesser hit-ratio. This gives a realistic description of the local processes forming the recrystallization topology in unstructured peer-to-peer network. We calculate analytically the degree distribution. The analytic result indicates that the constructed network is a scale-free network, of which the scaling exponent is 3.

Validity and Reliability of the Assessment Tool for Measuring Communication Skills of Dental Hygienist (치과위생사의 커뮤니케이션 기술 측정을 위한 평가 도구의 타당도와 신뢰도)

  • Moon, Hak-Jin;Lee, Soo-Young;Lim, Soon-Ryun
    • Journal of dental hygiene science
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    • v.14 no.2
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    • pp.198-206
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    • 2014
  • The purpose of this study was to develop and validate tool for measuring the communication skills of dental hygienist. The survey was modified and revised to fit into Korean culture. Also the reliability and validity was tested in order to ensure the survey was properly evaluating communication skills of dental hygienists. A survey was conducted with outpatients in dental clinics located in Seoul, Gyeonggi, and Daejeon area. The 483 answers out of the total collected answers were used for the final analysis of the study, using PASW Statistics 18.0 and IBM SPSS AMOS 7.0 to measure the validity and reliability. The factor analysis showed that the communication skill of the dental hygienists was composed of three elements, namely 'being caring and respectful' communications, 'sharing information' communications and 'tending to comfort' communications to reduce pain and anxiety. The validity of the model examined by a confirmatory factor analysis satisfied most of the relevant requirements. All of the factors had the conceptual reliability and variant extracted index above the minimum requirements, ensuring reliability and concentrated validity. Also, the value of the square of the correlations between all latent factors which was larger than the square of the correlation between all of the factors, thus proving the discriment validity. Cronbach's ${\alpha}$ was 0.8, which shows high reliability level. In conclusion, it was proven that dental hygienist's communication skill measurement tool has high validity and reliability. Further, this study can be used to improve dental hygienists' communication skills. Therefore, this will improve oral health of clients and manage them.

A Study on Price Volatility and Properties of Time-series for the Tangerine Price in Jeju (제주지역 감귤가격의 시계열적 특성 및 가격변동성에 관한 연구)

  • Ko, Bong-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.6
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    • pp.212-217
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    • 2020
  • The purpose of this study was to analyze the volatility and properties of a time series for tangerine prices in Jeju using the GARCH model of Bollerslev(1986). First, it was found that the time series for the rate of change in tangerine prices had a thicker tail rather than a normal distribution. At a significance level of 1%, the Jarque-Bera statistic led to a rejection of the null hypothesis that the distribution of the time series for the rate of change in tangerine prices is normally distributed. Second, the correlation between the time series was high based on the Ljung-Box Q statistic, which was statistically verified through the ARCH-LM test. Third, the results of the GARCH(1,1) model estimation showed statistically significant results at a significance level of 1%, except for the constant of the mean equation. The persistence parameter value of the variance equation was estimated to be close to 1, which means that there is a high possibility that a similar level of volatility will be present in the future. Finally, it is expected that the results of this study can be used as basic data to optimize the government's tangerine supply and demand control policy.

The Effects of Physical Education Major Learner's Social Support on Major Satisfaction and Learning Persistence in the Academic Credit Bank System (학점은행제 체육학전공 학습자의 사회적지지가 전공만족 및 학습지속의향에 미치는 영향)

  • Oh, Kyung-A
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.4
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    • pp.1008-1019
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    • 2020
  • The purpose of this study is to investigate the effects of social support of students majoring in physical education on their major satisfaction and intention to continue learning, and to prevent dropout of students majoring in physical education in the credit banking system and to find effective management methods. The research tools were verified by confirmatory factor analysis, concentration validity, discriminant validity, average variance extraction (AVE), concept reliability, and Cronbach's coefficient for validity and reliability verification of the research tools. The data processing method was conducted by using IBM SPSS Statistics 21 and IBM AMOS 21 to verify reliability analysis, correlation analysis, and structural equation model (SEM) through frequency analysis, confirmatory factor analysis, concentration validity, discriminant validity, Cronbach's coefficient calculation. The results are as follows. First, the study model was tested and the criteria were met for verifying the suitability of the relationship between social support, major satisfaction and learning persistence intention of the professors majoring in physical education in credit banking system. Second, as a result of the verification of Hypothesis 1, the social support of the professor of the physical education major in the credit banking system has a significant effect on the major satisfaction. The results of the verification of Hypothesis 2 showed that the social support of the professor of the physical education major in the credit banking system affects on the learning persistence. As a result of the verification of Hypothesis 3, it has been shown that major satisfaction has a significant effect on the learning persistence.