• 제목/요약/키워드: analysis

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Topic Analysis of Scholarly Communication Research

  • Ji, Hyun;Cha, Mikyeong
    • Journal of Information Science Theory and Practice
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    • 제9권2호
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    • pp.47-65
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    • 2021
  • This study aims to identify specific topics, trends, and structural characteristics of scholarly communication research, based on 1,435 articles published from 1970 to 2018 in the Scopus database through Latent Dirichlet Allocation topic modeling, serial analysis, and network analysis. Topic modeling, time series analysis, and network analysis were used to analyze specific topics, trends, and structures, respectively. The results were summarized into three sets as follows. First, the specific topics of scholarly communication research were nineteen in number, including research resource management and research data, and their research proportion is even. Second, as a result of the time series analysis, there are three upward trending topics: Topic 6: Open Access Publishing, Topic 7: Green Open Access, Topic 19: Informal Communication, and two downward trending topics: Topic 11: Researcher Network and Topic 12: Electronic Journal. Third, the network analysis results indicated that high mean profile association topics were related to the institution, and topics with high triangle betweenness centrality, such as Topic 14: Research Resource Management, shared the citation context. Also, through cluster analysis using parallel nearest neighbor clustering, six clusters connected with different concepts were identified.

A Prediction of Stock Price Movements Using Support Vector Machines in Indonesia

  • ARDYANTA, Ervandio Irzky;SARI, Hasrini
    • The Journal of Asian Finance, Economics and Business
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    • 제8권8호
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    • pp.399-407
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    • 2021
  • Stock movement is difficult to predict because it has dynamic characteristics and is influenced by many factors. Even so, there are some approaches to predict stock price movements, namely technical analysis, fundamental analysis, and sentiment analysis. Many researches have tried to predict stock price movement by utilizing these analysis techniques. However, the results obtained are varied and inconsistent depending on the variables and object used. This is because stock price movement is influenced by a variety of factors, and it is likely that those studies did not cover all of them. One of which is that no research considers the use of fundamental analysis in terms of currency exchange rates and the use of foreign stock price index movement related to the technical analysis. This research aims to predict stock price movements in Indonesia based on sentiment analysis, technical analysis, and fundamental analysis using Support Vector Machine. The result obtained has a prediction accuracy rate of 65,33% on an average. The inclusion of currency exchange rate and foreign stock price index movement as a predictor in this research which can increase average prediction accuracy rate by 11.78% compared to the prediction without using these two variables which only results in average prediction accuracy rate of 53.55%.

Simplified elastic-plastic analysis procedure for strain-based fatigue assessment of nuclear safety class 1 components under severe seismic loads

  • Kim, Jong-Sung;Kim, Jun-Young
    • Nuclear Engineering and Technology
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    • 제52권12호
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    • pp.2918-2927
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    • 2020
  • This paper proposes a simplified elastic-plastic analysis procedure using the penalty factors presented in the Code Case N-779 for strain-based fatigue assessment of nuclear safety class 1 components under severe seismic loads such as safety shutdown earthquake and beyond design-basis earthquake. First, a simplified elastic-plastic analysis procedure for strain-based fatigue assessment of nuclear safety class 1 components under the severe seismic loads was proposed based on the analysis result for the simplified elastic-plastic analysis procedure in the Code Case N-779 and the stress categories corresponding to normal operation and seismic loads. Second, total strain amplitude was calculated directly by performing finite element cyclic elastic-plastic seismic analysis for a hot leg nozzle in pressurizer surge line subject to combined loading including deadweight, pressure, seismic inertia load, and seismic anchor motion, as well as was derived indirectly by applying the proposed analysis procedure to the finite element elastic stress analysis result for each load. Third, strain-based fatigue assessment was implemented by applying the strain-based fatigue acceptance criteria in the ASME B&PV Code, Sec. III, Subsec. NB, Article NB-3200 and by using the total strain amplitude values calculated. Last, the total strain amplitude and the fatigue assessment result corresponding to the simplified elastic-plastic analysis were compared with those using the finite element elastic-plastic seismic analysis results. As a result of the comparison, it was identified that the proposed analysis procedure can derive reasonable and conservative results.

A Study on the Sentiment Analysis of City Tour Using Big Data

  • Se-won Jeon;Gi-Hwan Ryu
    • International Journal of Internet, Broadcasting and Communication
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    • 제15권2호
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    • pp.112-117
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    • 2023
  • This study aims to find out what tourists' interests and perceptions are like through online big data. Big data for a total of five years from 2018 to 2022 were collected using the Textom program. Sentiment analysis was performed with the collected data. Sentiment analysis expresses the necessity and emotions of city tours in online reviews written by tourists using city tours. The purpose of this study is to extract and analyze keywords representing satisfaction. The sentiment analysis program provided by the big data analysis platform "TEXTOM" was used to study positives and negatives based on sentiment analysis of tourists' online reviews. Sentiment analysis was conducted by collecting reviews related to the city tour. The degree of positive and negative emotions for the city tour was investigated and what emotional words were analyzed for each item. As a result of big data sentiment analysis to examine the emotions and sentiments of tourists about the city tour, 93.8% positive and 6.2% negative, indicating that more than half of the tourists are positively aware. This paper collects tourists' opinions based on the analyzed sentiment analysis, understands the quality characteristics of city tours based on the analysis using the collected data, and sentiment analysis provides important information to the city tour platform for each region.

악안면 기형의 상하악골 전후방적 위치관계에 대한 McNamara Analysis와 Delaire Analysis의 기준선 비교연구 (Comparative Analysis of the Reference Lines on McNamara's and Delaire's Analyses for the Anterior and Posterior Facial Relationship of Maxillofacial Deformity)

  • 정승원;김소미;변성수;박형식;정영수
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제33권4호
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    • pp.331-336
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    • 2011
  • Purpose: McNamara and Delaire analyses are two commonly used analytic methods, yet, they differ in their theoretic concepts and different reference lines are used for ideal surgical prediction. Therefore, the use of different analytic methods may result in different surgical plans. The purpose of this study was to compare the anterior and posterior relationship of the maxilla and mandible by using McNamara and Delaire analysis. Methods: 30 Korean patients (15 male and 15 female) who had visited the Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, for dentofacial evaluation were studied by using McNamara's and Delaire's analyses. Results: On the maxillary analysis, 26 out of 30 patients (86.7%) were in accordance. On the mandibular analysis, 20 out of 30 patients (66.7%) were in accordance. On the maxillary analysis, McNamara's analysis showed an average of 0.36 mm greater amount of prognathism compared to Delaire's analysis, and this was not statistically significant. On the mandibular analysis, McNamara's analysis showed an average of 6.03 mm greater amount of prognathism compared to Delaire's analysis, and this was statistically significant. On the mandibular analysis, 26 out of 30 patients (86.7%) showed a greater amount of prognathism on McNamara's analysis compared to that of Delaire's analysis. The remaining 4 patients (13.3%) showed the same amount of prognathism on both analyses. Conclusion: These results may serve as a reference for surgeons when determining which analytic method is to be used for optimal surgical results.

Comparison of authorized feed analysis laboratories in Korea: looking at feed chemical analysis

  • Jeon, Seoyoung;Lee, Jun-Sung;Park, Seong-Min;Ki, Kwang-Seok;Seo, Seongwon
    • 농업과학연구
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    • 제44권1호
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    • pp.86-94
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    • 2017
  • In Korea, chemical analysis of animal feed is done through authorized feed analysis laboratories (AFALs). Analysis results among the AFALs need to be similar or within acceptable variations; however, there is no experimental evidence of their comparability. We aimed to determine the level of variation of feed chemical analysis results from different AFALs. For this, we requested analysis of four kinds of feed (corn, soybean meal, corn gluten feed, and ryegrass) to eight AFALs and the Cumberland Valley Analytical Services (CVAS) which is an internationally well-recognized feed analysis laboratory. The AFALs spent more time on analysis than did CVAS. Fiber analysis results varied significantly among laboratories. However, moisture, CP, and ash content values showed almost no variation. At least one AFAL obtained results with significant differences from CVAS for all tested values. These differences can be explained by the followings: 1) the standard methods for feed analysis (SMFA) established for AFALs are not detailed enough to control the analytical variations among different laboratories and 2) guidelines are insufficient for the quality control of analysis results in Korea. Failure to accurately identify the nutritional components of the feed could mean failure to provide adequate nutrients to the animals. Therefore, efforts to reduce the differences among AFALs, such as revising SMFA and publishing guidelines on quality control of feed analysis results, are important.

사상체질 분류모형 개발 및 진단시스템의 구현에 관한 연구 (Study on Development of Classification Model and Implementation for Diagnosis System of Sasang Constitution)

  • 범수균;전미란;오암석
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 지능정보 및 응용 학술대회
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    • pp.155-159
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    • 2008
  • 본 논문에서는 사상체질분류검사 설문지를 이용하여 사상체질을 진단할 때 진단의 정확도를 향상시키기 위한 사상체질 분류모형을 개발하기 위하여 데이터마이닝의 주요 분류기법인 판별분석(discriminant analysis), 의사결정나무(decision tree analysis), 신경망분석(neural network analysis), 로지스틱 회귀분석(logistic regression analysis), 군집분석(clustering analysis) 등 다양한 분류분석모형을 이용한다. 본 연구에서는 분류의 비교적 정확도가 우수하며, 특히 분석과정을 쉽게 이해하고 설명할 수 있다는 점과 구현이 용이하다는 장점을 가지고 있는 판별분석모형과 의사결정나무분석모형을 기반으로 사상체질 분류모형을 개발하고, 두 분류모형을 적용한 사상체질 진단시스템을 구현하였다.

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가중주성분분석을 활용한 정준대응분석과 가우시안 반응 모형에 의한 정준대응분석의 동일성 연구 (Equivalence study of canonical correspondence analysis by weighted principal component analysis and canonical correspondence analysis by Gaussian response model)

  • 정형철
    • 응용통계연구
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    • 제34권6호
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    • pp.945-956
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    • 2021
  • 본 연구에서는 가중주성분분석으로부터 정준대응분석을 유도하는 Legendre와 Legendre (2012)의 알고리즘을 고찰하였다. 그리고, 가중주성분분석에 기반한 Legendre와 Legendre (2012)의 정준대응분석이 가우시안 반응모형에 기초한 Ter Braak (1986)의 정준대응분석과 동일함을 다루었다. 생태학에서 종의 발현 정도를 잘 설명할 수 있는 가우시안 반응곡선에서 도출된 Ter Braak (1986)의 정준대응분석은 종 패킹 모형(species packing model)이라는 기본 가정을 사용한 후 일반화선형모형과 정준상관분석을 결합시키는 방법으로 도출된다. 그런데 Legendre와 Legendre (2012)의 알고리즘은 이러한 가정없이 Benzecri의 대응분석과 상당히 유사한 방법으로 계산되는 특징을 지닌다. 그러므로 가중주성분석에 기초한 정준대응분석을 사용하면, 결과물 활용에 약간의 유연성을 지닐 수 있게 된다. 결론적으로 본 연구에서는 서로 다른 모형에서 출발한 두 방법이 장소점수(site score), 종 점수(species score) 그리고 환경변수와의 상관관계가 서로 동일함을 보인다.

경영정보의 인과구조 구축을 위한 다변량통계기법 적용에 관한 연구 (A study on applying multivariate statistical method for making casual structure in management information)

  • 조성훈;김태성
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1996년도 추계학술대회발표논문집; 고려대학교, 서울; 26 Oct. 1996
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    • pp.117-120
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    • 1996
  • The objective of this study is to suggest modified Covariance Structure Analysis that combine with existing Multivariate Statistical Method which is used Casual Analysis Method in Management Information. For this purpose, we'll consider special feature and limitation about Correlation Analysis, Regression Analysis, Path Analysis and connect Covariance Structure Analysis with Statistical Factor Analysis so that theoretical casual model compare with variables structure in collecting data. A example is also presented to show the practical applicability of this approach.

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