• 제목/요약/키워드: cross correlation analysis

검색결과 1,290건 처리시간 0.024초

A vision-based system for dynamic displacement measurement of long-span bridges: algorithm and verification

  • Ye, X.W.;Ni, Y.Q.;Wai, T.T.;Wong, K.Y.;Zhang, X.M.;Xu, F.
    • Smart Structures and Systems
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    • 제12권3_4호
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    • pp.363-379
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    • 2013
  • Dynamic displacement of structures is an important index for in-service structural condition and behavior assessment, but accurate measurement of structural displacement for large-scale civil structures such as long-span bridges still remains as a challenging task. In this paper, a vision-based dynamic displacement measurement system with the use of digital image processing technology is developed, which is featured by its distinctive characteristics in non-contact, long-distance, and high-precision structural displacement measurement. The hardware of this system is mainly composed of a high-resolution industrial CCD (charge-coupled-device) digital camera and an extended-range zoom lens. Through continuously tracing and identifying a target on the structure, the structural displacement is derived through cross-correlation analysis between the predefined pattern and the captured digital images with the aid of a pattern matching algorithm. To validate the developed system, MTS tests of sinusoidal motions under different vibration frequencies and amplitudes and shaking table tests with different excitations (the El-Centro earthquake wave and a sinusoidal motion) are carried out. Additionally, in-situ verification experiments are performed to measure the mid-span vertical displacement of the suspension Tsing Ma Bridge in the operational condition and the cable-stayed Stonecutters Bridge during loading tests. The obtained results show that the developed system exhibits an excellent capability in real-time measurement of structural displacement and can serve as a good complement to the traditional sensors.

저주파수 레이더(GPR)에 의한 콘크리트 상판 및 터널 라이닝 배면 공동의 크기 및 두께 추정에 관한 실험 연구 (An Experimental Study on Estimation of Size and Thickness of Cavitation(Void)s under Concrete Slabs and Tunnel Linings Using Law Frequency Type Radar(GPR))

  • 박석균
    • 한국구조물진단유지관리공학회 논문집
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    • 제10권6호
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    • pp.95-104
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    • 2006
  • 콘크리트 도로 상판 또는 터널 라이닝의 배면 공동은 구조물의 함몰 또는 붕괴로까지 이어질 가능성이 있다. 이 공동을 비파괴로 검출하기 위한 방법 중의 하나가 저주파수대 레이더(GPR)의 사용이다. 그러나 이와 같은 토목구조물에는 분해능이 좋지 않은 저주파수대의 레이더를 사용할 수밖에 없기 때문에 작은 공동의 크기나 두께까지 탐사하는 일은 현재 기술로는 거의 불가능하다. 본 연구는 이와 같은 문제와 한계를 극복하기 위해 다양한 공동의 크기와 두께, 깊이를 대상으로 많은 량의 실측 실험을 통해, 저주파 레이더 측정치와 공동 간의 상관관계를 분석함으로 해서 공동의 깊이, 크기와 두께까지를 추정하기 위한 새로운 해석방법을 제안하고 그 적용성을 검토하였다. 또한 본 검토에서는 공동만을 그 크기(횡폭)에 맞게 화상처리에 의해 나타낼 수 있는 역치를 산정하였다. 그 결과, 본 연구에서 제안된 방법에 의해 실험실 수준에서는 정도 좋게 공동의 깊이와 크기, 두께를 추정하는 것이 가능하였다.

압전류적 면역센서에 의한 잉어 Vitellogenin 검출 (Detection of Carp Vitellogenin with Piezoelectric Immunosensor)

  • 김남수;박인선;김우연
    • Applied Biological Chemistry
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    • 제49권3호
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    • pp.254-258
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    • 2006
  • 내분비계장애물질에 노출된 어류의 에스트로겐 활성에 대한 생물지표단백질인 vitellogenin을 검출하는 압전류적 면역센서를 잉어 vitellogenin에 대한 항체와 AT-cut 수정진동자를 생물요소와 변환기로 사용하여 구성하고 이를 이용한 잉어 vitellogenin 검출을 행하였다. 이형이기능성의 티올화 가교화제인 sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate 처리에 의하여 티올화된 항체를 수정진동자상의 금전극에 화학흡착법에 의하여 고정화하여 센서 chip을 제조하였다. 센서반응을 위한 반응완충용액을 0.1M sodium phosphate(pH 7.4)로 선정한 후 $0.4864{\sim}486.4000\;nM$의 vitellogenin 용액을 가하였을 때 농도의존적인 센서반응의 증가가 나타났으며 이 때 잉어 vitellogenin에 대한 검출한계는 0.4864 nM로 추정되었다.

지역사회거주 여성의 비만도와 골밀도와의 관계 (Relationship of Obesity and Bone Mineral Density in Women Dwelling in the Community)

  • 강현숙;김종임;박원숙;송라윤;안양희;이인옥;임난영;조경숙;최선하;한상숙
    • 근관절건강학회지
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    • 제14권2호
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    • pp.181-187
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    • 2007
  • Purpose: The purpose of the study was to identify the relationship between obesity and bone mineral density in middle aged women. Methods: A cross-sectional survey design was utilized with a check list and physiological measurements. A total of 827 convenient samples were recruited from women who lived in the community. Bone mineral density was measured by T-score using the pixi method of Lumar on the left heel. Descriptive statistics and pearson correlation coefficient were utilized for data analysis. Results: Most were assessed as having normal weight(37.9%) or obese (57.4%) by BMI. Only 32% was assessed as having normal bone mineral density, while 40.3% had osteopenia, and 27.7% as osteoporosis. The BMI scores were significantly related to age, and episodes of fractures. Those with lower bone mineral density reported significantly more episodes of fractures and chronic disease. The T scores of Bone mineral density were significantly correlated with the scores of BMI (r= .126, p< .001). Conclusion: There is a strong need to develop intervention programs for this age group to manage bone mineral density loss to prevent occurrences of osteoporosis, and episodes of fracture.

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장액성 난소암 환자의 유전성 난소암에 대한 지식 및 불안정도 (Knowledge and Anxiety Related to Hereditary Ovarian Cancer in Serous Ovarian Cancer Patients)

  • 이상희;이향규;임명철;김수
    • 여성건강간호학회지
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    • 제25권4호
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    • pp.365-378
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    • 2019
  • Purpose: The awareness of hereditary breast and ovarian cancer (HBOC) and BRCA testing is increasing in Korea. Compared to the sizable research on HBOC knowledge among breast cancer women, studies in the ovarian cancer population are limited. This paper aimed to investigate the level of knowledge of hereditary ovarian cancer and anxiety in women diagnosed with serous ovarian cancer in Korea and determine differences in the knowledge and anxiety according to whether genetic testing was undertaken and whether BRCA1 or BRCA2 mutations were present. Methods: Using a descriptive research design, a cross-sectional survey was conducted on 100 women diagnosed with serous ovarian cancer at N hospital in Gyeonggi-do, Korea, from July to November 2018. The collected data were analyzed by descriptive statistics, independent t-tests, one-way analysis of variance, and Pearson's correlation coefficient using the SPSS 21.0 program. Results: The hereditary ovarian cancer-related knowledge score was mid-level (mean score 8.90±3.29 out of a total of 17), as was the state anxiety level was mid-level (mean score 47.96±3.26 out of possible score range of 20-80). Genetic knowledge of hereditary ovarian cancer was associated with age, education, occupation, genetic counseling, and BRCA mutations. There were no statistically significant factors related to anxiety and there were no statistically significant correlations between knowledge level and anxiety. Conclusion: More comprehensive education on gene-related cancer is needed for ovarian cancer patients, especially for items with low knowledge scores. A genetic counseling protocol should be developed to allow more patients to alleviate their anxiety through genetic counseling.

대사증후군 위험군의 가족기능과 건강행위의 관계에서 질병인식의 매개효과 (Mediating Effect of Illness Perception on the Relationship between Family Function and Health Behavior in Patients with Risk Factors for Metabolic Syndrome)

  • 염현이;신지원;김세현;신선의
    • 동서간호학연구지
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    • 제25권2호
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    • pp.183-192
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    • 2019
  • Purpose: This study aimed to examine the mediating effect of illness perception on the relationship between family function and health behavior of patients with risk factors for metabolic syndrome. Methods: This is a cross-sectional correlational study. Data were collected from 160 patients using self-administered questionnaires including the Illness Perception Questionnaire-Revised, Family APGAR, and the Health Behavior Scale. The data were analyzed using Pearson's correlation coefficients, independent t-test and multiple linear regression analysis by the SPSS 23.0 program. Results: Health behavior was significantly correlated with family function (r=.30, p<.001) and illness perception of controllability by treatment (r=-.21, p=.007). Family function was a significant predictor of health behavior and illness perception, and the influence of family function on health behavior was partially mediated by illness perception of controllability by treatment. Conclusion: The findings of this study indicate that family function is a critical factor affecting health behavior and illness perception, and illness perception of controllability by treatment mediates the influence of family function on health behavior. It is necessary to develop a psycho-cognitive intervention program for enhancing supportive family function and for modifying negative illness perceptions to improve health behavior in patients with risk factors for metabolic syndrome.

산후 초기여성의 모성기능에 미치는 영향요인 (Factors affecting maternal functioning among early postpartum women)

  • 반민경;여정희
    • 한국융합학회논문지
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    • 제12권9호
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    • pp.323-330
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    • 2021
  • 본 연구는 출산여성의 모성기능의 정도와 이에 영향을 미치는 요인을 규명하기 위해 시도되었다. 자료수집은 2021년 2-3월에 걸쳐 여성병원 3곳에서 출산 후 6주에서 12주에 해당되는 여성 243명을 대상으로 실시하였고, 이 자료는 SPSS 25.0 프로그램을 이용하여 분석되었다. 그 결과 출산여성의 모성기능 영향요인은 산후우울, 배우자 및 가족지지, 직업유무, 출산 방법으로 나타났으며, 그 중 산후우울(β=-0.43, p<.001)과 배우자 및 가족 지지(β=0.39, p<.001)가 중요한 예측인자였다. 따라서 모성기능 향상을 위한 중재 개발 및 적용 시 산후우울을 완화하고 배우자 및 가족지지를 증진하는데 중점을 둘 필요가 있다. 본 연구는 국내에서 처음으로 출산여성의 모성기능을 파악하여 다양한 연구의 시발점이 될 것이다.

대학생의 부정적 심리성향과 학업열의가 자기주도적 학습능력에 미치는 영향 (Effects of Academic Engagement and Negative Psychological Tendency on Self-Directed Learning Ability among Undergraduate Students)

  • 안민정;노주연;장혜주;최주혜;한도헌;한수진;송지은;황윤영
    • 한국학교보건학회지
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    • 제32권2호
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    • pp.67-76
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    • 2019
  • Purpose: The purpose of this study was to explore self-directed learning ability and its affecting factors among undergraduate students. Methods: A descriptive cross-sectional study design was used. Using a convenience sampling method, data were collected from 196 undergraduate students enrolled in one national university. Negative psychological tendency (i.e. Type D personality), academic engagement, and self-directed learning ability were assessed using a structured questionnaire. Data were analyzed by descriptive statistics, t-test, and analysis of covariance, Pearson's correlation coefficients, and stepwise multiple linear regression, using SPSS/WIN 23.0 program. Results: The mean age of the students was $21.61{\pm}2.40years$ and 56.6% were male students. Approximately, one third (n=67, 34.2%) of the students had Type D personality. The average scores of academic engagement and self-directed learning ability were $3.01{\pm}1.14$ and $3.46{\pm}0.50$, respectively. After controlling for sociodemographic variables, the Type D personality and academic engagement were significant predictors of self-directed learning ability (${\beta}=.64$, p<.001; ${\beta}=-.13$, p=.021, respectively). This model explained 53.6% of the variance in self-directed learning ability. Conclusion: The study identified that Type D personality and academic engagement affect self-directed learning ability of undergraduate students, one in a negative way, the other in a positive way. Educators and educational policy makers need to make efforts to include interventions and strategies that increase academic engagement and change negative psychological dispositions such as D-type personality in the undergraduate education curriculum.

응급실 간호사의 감염관리 조직문화와 자기효능감이 표준주의 지침 수행에 미치는 영향 (The Effects of Organizational Culture for Infection Control and Self-Efficacy on Compliance with Standard Precautions of Emergency Room Nurses)

  • 김현희;박형란
    • Journal of Korean Biological Nursing Science
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    • 제21권1호
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    • pp.46-53
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    • 2019
  • Purpose: This study was conducted to identify the effects of organizational culture for the infection control and self-efficacy on compliance with standard precautions of emergency room nurses. Methods: This cross-sectional descriptive study was conducted from 1st July to 3rd August, 2017. The participants were 200 nurses working in emergency rooms. The data was collected using structured self-report questionnaires. Results: The average scores for the organizational culture for infection control, self-efficacy and compliance with standard precautions were 5.54, 3.65, and 4.31, respectively. The organizational culture for infection control (r = .59, p< .001) and self-efficacy (r= .28, p< .001) were found to have a positive, meaningful correlation with compliance with the standard precautions. Multiple regression analysis showed that compliance with standard precautions was significantly affected by the organizational culture for infection control (${\beta}=0.55$, p< .001) and self-efficacy (${\beta}=0.13$, p= .033). Conclusion: The results for this study indicate that the organizational culture for infection control and self-efficacy were highly influential factors affecting compliance with standard precautions of emergency room nurses. Therefore, in order to improve the nurses' use of the standard precautions, it was necessary to develop and evaluate a program that considers the environmental factors and self-efficacy.

일교차가 당뇨병성 창상의 치유에 미치는 영향: 동물 실험 연구 (Relationship between the Diurnal Temperature Range and Wound Healing of Diabetic Foot: Animal Study)

  • 원성훈;천동일;조재호;박인근;이영
    • 대한족부족관절학회지
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    • 제24권4호
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    • pp.142-147
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    • 2020
  • Purpose: Diabetic foot ulcers are closely related to body surface heat, which can be affected easily by temperature differences. This study examined the correlation between the healing process of diabetic wounds and abnormal diurnal temperature through an animal study. Materials and Methods: Rats in the abnormal diurnal temperature group and control group were given a 10 mm sized full-thickness skin ulcer. Wound size progression was observed in both groups. H&E and Masson's trichrome staining was performed at 14 days after wound formation, and the number of vessels per unit area and histology analysis were performed. The changes in the ulcer were measured through three dimensional cross-section area using INSIGHT® devices. Results: The wound recovery period (granulation ingrowing) was 24 days in the abnormal diurnal temperature model and 20 days in the control group. The thickness of scar tissue was 402±23.19 ㎛ in the control group and 424.5±36.94 ㎛ in the diurnal temperature model. Neovascular formation was counted as 5.1±0.97 for the control group and 4.16±0.94 for the diurnal temperature model group. Conclusion: Delayed and inferior diabetic wound healing was observed in the abnormal diurnal temperature group, which was characterized by greater diurnal variations than the typical growth environment.