• Title/Summary/Keyword: Pearson's Correlation Coefficient

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Correlation Analysis of Atmospheric Pollutants and Meteorological Factors Based on Environmental Big Data

  • Chao, Chen;Min, Byung-Won
    • International Journal of Contents
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    • v.18 no.1
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    • pp.17-26
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    • 2022
  • With the acceleration of urbanization and industrialization, air pollution has become increasingly serious, and the pollution control situation is not optimistic. Climate change has become a major global challenge faced by mankind. To actively respond to climate change, China has proposed carbon peak and carbon neutral goals. However, atmospheric pollutants and meteorological factors that affect air quality are complex and changeable, and the complex relationship and correlation between them must be further clarified. This paper uses China's 2013-2018 high-resolution air pollution reanalysis open data set, as well as statistical methods of the Pearson Correlation Coefficient (PCC) to calculate and visualize the design and analysis of environmental monitoring big data, which is intuitive and it quickly demonstrated the correlation between pollutants and meteorological factors in the temporal and spatial sequence, and provided convenience for environmental management departments to use air quality routine monitoring data to enable dynamic decision-making, and promote global climate governance. The experimental results show that, apart from ozone, which is negatively correlated, the other pollutants are positively correlated; meteorological factors have a greater impact on pollutants, temperature and pollutants are negatively correlated, air pressure is positively correlated, and the correlation between humidity is insignificant. The wind speed has a significant negative correlation with the six pollutants, which has a greater impact on the diffusion of pollutants.

Image registration using outlier removal and triangulation-based local transformation (이상치 제거와 삼각망 기반의 지역 변환을 이용한 영상 등록)

  • Ye, Chul-Soo
    • Korean Journal of Remote Sensing
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    • v.30 no.6
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    • pp.787-795
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    • 2014
  • This paper presents an image registration using Triangulation-based Local Transformation (TLT) applied to the remaining matched points after elimination of the matched points with gross error. The corners extracted using geometric mean-based corner detector are matched using Pearson's correlation coefficient and then accepted as initial matched points only when they satisfy the Left-Right Consistency (LRC) check. We finally accept the remaining matched points whose RANdom SAmple Consensus (RANSAC)-based global transformation (RGT) errors are smaller than a predefined outlier threshold. After Delaunay triangulated irregular networks (TINs) are created using the final matched points on reference and sensed images, respectively, affine transformation is applied to every corresponding triangle and then all the inner pixels of the triangles on the sensed image are transformed to the reference image coordinate. The proposed algorithm was tested using KOMPSAT-2 images and the results showed higher image registration accuracy than the RANSAC-based global transformation.

The Analysis of Correlation Between COVID-19 and Seoul Small Business Commercial Districts (코로나 19와 서울 소상공인 상권의 상관관계 분석)

  • Kim, Jae-Ho;Kim, Jang-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.3
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    • pp.384-388
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    • 2021
  • Currently, whether in a domestic or international sphere, many small businesses are suffering due to COVID-19. The grim reality is that several businesses are shutting down. While the national disaster relief grant was used to contain the damages by encouraging consumer spending, it has become difficult to prevent closures of small businesses. As of September 2020, more than 20,000 stores have closed in Seoul due to the COVID-19 pandemic. There has also been an increase in the number of people with depression caused by the COVID-19 blues. This issue is not only confined to Seoul in the Republic of Korea, but is influencing all other areas affected by the pandemic. As the number of COVID-19 patients increase, the number of open stores is decreasing steadily. The analysis of the correlation coefficient of Pearson, Spearman, and Kendall suggests a negative correlation between the number of COVID-19 patients and the number of stores in business.

An Approach to Credibility Enhancement of Automated Collaborative Filtering System through Accommodating User's Rating Behavior

  • Sung, Jang-Hwan;Park, Jong-Hun
    • 한국경영정보학회:학술대회논문집
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    • 2007.06a
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    • pp.576-581
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    • 2007
  • The purpose of this paper is to strengthen trust on the automated collaborative filtering system. Automated collaborative filtering system is quickly becoming a popular technique for recommendation system. This elaborative methodology contributes for reducing information overload and the result becomes index of users' preference. In addition, it can be applied to various industries in various fields. After it collaborative filtering system was developed, many researches are executed to enhance credibility and to apply in various fields. Among these diverse systems, collaborative filtering system which uses Pearson correlation coefficient is most common in many researches. In this paper, we proposed new process diagram of collaborative filtering algorithm and new factors which should improve the credibility of system. In addition, the effects and relationships are also tested.

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Influence of Cortical Endplates on Ultrasonic Properties of Trabecular Bone (피질골판이 해면질골의 초음파 특성에 미치는 영향)

  • Kim, Yoon Mi;Lee, Kang Il
    • Journal of the Korean Society for Nondestructive Testing
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    • v.35 no.2
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    • pp.103-111
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    • 2015
  • The present study investigated the influence of thick cortical endplates on the ultrasonic properties of trabecular bone in a femur with a high fracture risk. Twelve trabecular bone samples were prepared from bovine femurs, and acrylic plates with thicknesses of 1.25, 1.80, and 2.75 mm were manufactured to simulate the cortical endplates using acrylic with a density and a sound speed similar to cortical bone. Although the thickness of the acrylic plates attached to the two sides of the trabecular bone increased, high correlations were observed between the speed of sound and the apparent bone density of the trabecular bone, with Pearson's correlation coefficients of 0.80-0.86. High correlations were also observed between the attenuation coefficient at 0.5 MHz and the apparent bone density of the trabecular bone, with Pearson's correlation coefficients of 0.84-0.91. These results suggest that the speed of sound and attenuation coefficient at a specific frequency measured in a femur with relatively thick cortical endplates compared to the calcaneus could be used as indices for predicting the bone mineral density of the femur.

Effects of Academic Stress, Academic Self-Efficacy and Major Satisfaction in Nursing Student on Grit (간호대학생의 학업스트레스, 학업적 자기효능감, 전공만족도가 그릿(Grit)에 미치는 영향)

  • Jung, Mi-Ra;Jeong, Eun
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.414-423
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    • 2018
  • The purpose of this study was to examine influences on grit in the nursing student. The data were collected from 146 nursing students in the H university located Y city. The data were analyzed by descriptive statistics, T-test, ANOVA, Scheffe, Pearson's correlation coefficient, and multiple regression with SPSS 20.0 program. Grit was found to be in a significant positive correlation with academic stress, academic self-efficacy and major satisfaction. The result of the multiple regression indicates the major satisfaction, academic self-efficacy, academic stress and grade point average predict 22.5% of grit. Therefore, it is necessary to develop an intervention program to strengthen the grit of nursing students.

Validity and Reliability of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)-VA3.0 in Hip and Knee Osteoarthritis Patients (WOMAC-VA3.0의 타당도 및 신뢰도 -일부 슬관절 및 고관절 골관절염환자를 대상으로-)

  • Yi, Seung-Ju;Lee, Hyun-Ju;Woo, Young-Keun
    • Physical Therapy Korea
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    • v.15 no.2
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    • pp.20-29
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    • 2008
  • The purpose of this study was to examine the validity and reliability of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)-VA3.0 in patients with hip and knee osteoarthritis (OA). The sample consisted of 301 patients who had received treatments at the physical therapy units of 5 medical institutions in Andong City in june 2006. Questionnaires on the WOMAC were recruited by 12 physical therapists. The internal structure and reliability of the scales were evaluated by means of item-internal consistency (Cronbach's alpha coefficient: ${\alpha}$), item-discriminant validity, and Pearson's relation coefficient. To explore construct validity, we conducted a principal component factor analysis with varimax rotation analysis. The criterion for factor extraction was an eigenvalue >1.0. The average age of the patients was 62.1 years. All WOMAC subscales (pain, stiffness, and physical function) were internally consistent with Cronbach's coefficients of .81, .91, and .80, respectively. The internal consistency reliability of item-each scale were also internally consistent with Cronbach's coefficient of .89 (Pearson's correlation coefficient: .71~.84), .93 (.89~.91), and .96 (.67~.91), respectively. However, high correlation was found among 3 items (.66~.83, .66~.67, and .67~.83), so the item-discriminant validity was low (${\alpha}$ coefficient: .81, .91, .80, respectively). The construct validity by factor analysis was low because it was not consistent With WOMAC-VA3.0. In conclusion, the results reported here confirm the reliability of the WOMAC in patients with OA of the hip and knee. The collection of information on the hip and knee osteoarthritis using this instrument was acceptable to patients. A further prospective multi-center study will be necessary to prove the construct validity.

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Development of an Evaluation Instrument for Service Quality in Nursing Homes (노인요양시설 서비스 질 평가 도구 개발)

  • Lee, Ji-A;Ji, Eun-Sun
    • Journal of Korean Academy of Nursing
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    • v.41 no.4
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    • pp.510-519
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    • 2011
  • Purpose: The purposes of this study were to identify the factors influencing service quality in nursing homes, and to develop an evaluation instrument for service quality. Methods: A three-phase process was employed for the study. 1) The important factors to evaluate the service quality in nursing homes were identified through a literature review, panel discussion and focus group interview, 2) the evaluation instrument was developed, and 3) validity and reliability of the study instrument were tested by factor analysis, Pearson correlation coefficient, Cronbach's ${\alpha}$ and Cohen's Kappa. Results: Factor analysis showed that the factors influencing service quality in nursing homes were healthcare, diet/assistance, therapy, environment and staff. To improve objectivity of the instrument, quantitative as well as qualitative evaluation approaches were adopted. The study instrument was developed with 30 items and showed acceptable construct validity. The criterion-related validity was a Pearson correlation coefficient of .85 in 151 care facilities. The internal consistency was Cronbach's ${\alpha}$=.95. Conclusion: The instrument has acceptable validity and a high degree of reliability. Staff in nursing homes can continuously improve and manage their services using the results of the evaluation instrument.

A Study on Female Sexual Dysfunction, Sexual Distress, Sexual Attitude and Knowledge in Korean Women (여성의 성기능 장애와 성 스트레스, 성태도 및 성지식과의 관계 연구)

  • Bae, Jeong-Yee
    • Women's Health Nursing
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    • v.10 no.4
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    • pp.342-350
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    • 2004
  • Purpose: It has been suggested that approximately 40% of women between 40 and 64 years of age cease their sexual activity. The aim of this study was to establish the basic data for FSD(female sexual dysfunction) and FSD-related factors in regional urban and rural areas of Korea. Method: Three hundred twenty five women over 20 years of age and resident in regional urban and rural areas were analyzed by a visit survey with an organized questionnaire. The female sexual function index(FSFI) for measurement of sexual dysfunction was used. The significance between the degree of sexual dysfunction and characteristics of the participants was analyzed by a t-test and ANOVA test. The relationship between the degree of sexual dysfunction and related factors was analyzed by Pearson's correlation coefficient. Results: All analyzing tools including the FSFI had a high validity for measuring. The FSFI in Korean women was $19.97{\pm}4.87$ and ranged from 2 to 29. Old age, menopause, medication, no contraception usage and longer marital duration were significantly related with a lower FSFI score. Pearson's correlation coefficient revealed the significance in degrees of sexual distress (r=-.469, p=.000), sexual attitude(r=.305, p=.000) and a stressful life event(r= -.141, p=.038) with the sexual function index score. Conclusion: Women with sexual dysfunction should be evaluated for these sexual function-related factors in the history taking, and this data can be a basis for study for sexual dysfunction.

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Correlation between the Asymmetric Ratio of Occlusal Force and the Thickness of the Middle Scalene Muscle (교합력 비대칭률과 중간 목갈비근 근육 두께의 비대칭률 상관관계)

  • Chae, Jung-Byung;Cho, Hyun-Rae
    • PNF and Movement
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    • v.14 no.1
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    • pp.53-57
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    • 2016
  • Purpose: This study aimed to examine the correlation between the asymmetric ratio of occlusal force of the temporomandibular joint and the thickness of the middle scalene muscle. Methods: The study measured the occlusal force of the right and left temporomandibular joints in 30 subjects (12 males and 18 females). Pearson's correlation analysis was performed to examine the effect of occlusal force on the asymmetric ratio of the thickness of their middle scalene muscles by measuring the force using ultrasound after the break. Results: The correlation between the asymmetric ratio of occlusal force and muscle thickness is 0.41, according to Pearson's correlation coefficient. Therefore, the result shows a moderate correlation with the asymmetric ratio of the temporomandibular joint depending on differences in the thickness of the middle scalene muscle. Conclusion: Based on the above results, the asymmetric ratio of occlusal force was found to correlate with the thickness of the middle scalene muscle. Thus, therapeutic intervention is required for the middle scalene muscle in the case of temporomandibular joint disorder.