• Title/Summary/Keyword: random effects

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Effects of Self Care Program on Hypertensive Control in Hypertensive Patient (고혈압환자에게 적용한 자가관리프로그램 중재 효과)

  • Kim, Ok-Ran
    • Research in Community and Public Health Nursing
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    • v.14 no.4
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    • pp.568-578
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    • 2003
  • This study was conducted to estimate the effects of self-care program on knowledge and symptoms related hypertension self-care and physiological index in essential hypertensive patients aged between 35-74 year. The subjects for the experiment group and the control group of this study were 70 men and women selected through random sampling from adults at Sangju Red Cross Hospital in Gyeongsanbuk-do, and the experiment was carried out during the period from the 15th of September to the 30th of April in 2002. This study measured systolic and diastolic blood pressure (SBP, DBP, the mean value of the two measures) and total cholesterol (TC) and surveyed the subjects' diet and life style in relation to hypertension using a self-report questionnaire. In order to study the significance of the effects of self-care program, the author carried out t-test, paired t-test, ANCOVA, chi-square analysis and effectiveness index (EI) analysis. Results of the study are as follows: The experiment group got higher mean scores than the control group in the degree of low sodium intake and the degree of high calcium and high potassium intake, and the difference was statistically significant(P<0.05). The effectiveness index of the self-care program in smoking was 0.797 at the 1st posttest and 0.601 at the 2nd posttest, and in physical activities 0.600 at the 1st posttest and 0.849 at the 2nd posttest. The rate of regular antihypertensive drugs intake of the experimental group was higher than that of the control group. and the effectiveness index of the self-care program was 0.715. The mean score of the systolic blood pressure of the experimental group was lower than that of the control group, and the difference was statistically significant(P<0.05). In conclusion, these findings support usefulness of self-care programs in reducing systolic blood pressure and in promoting self-care related to diet and life style for treating and preventing hypertension.

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A Reflectance Normalization Via BRDF Model for the Korean Vegetation using MODIS 250m Data (한반도 식생에 대한 MODIS 250m 자료의 BRDF 효과에 대한 반사도 정규화)

  • Yeom, Jong-Min;Han, Kyung-Soo;Kim, Young-Seup
    • Korean Journal of Remote Sensing
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    • v.21 no.6
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    • pp.445-456
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    • 2005
  • The land surface parameters should be determined with sufficient accuracy, because these play an important role in climate change near the ground. As the surface reflectance presents strong anisotropy, off-nadir viewing results a strong dependency of observations on the Sun - target - sensor geometry. They contribute to the random noise which is produced by surface angular effects. The principal objective of the study is to provide a database of accurate surface reflectance eliminated the angular effects from MODIS 250m reflective channel data over Korea. The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor has provided visible and near infrared channel reflectance at 250m resolution on a daily basis. The successive analytic processing steps were firstly performed on a per-pixel basis to remove cloudy pixels. And for the geometric distortion, the correction process were performed by the nearest neighbor resampling using 2nd-order polynomial obtained from the geolocation information of MODIS Data set. In order to correct the surface anisotropy effects, this paper attempted the semiempirical kernel-driven Bi- directional Reflectance Distribution Function(BRDF) model. The algorithm yields an inversion of the kernel-driven model to the angular components, such as viewing zenith angle, solar zenith angle, viewing azimuth angle, solar azimuth angle from reflectance observed by satellite. First we consider sets of the model observations comprised with a 31-day period to perform the BRDF model. In the next step, Nadir view reflectance normalization is carried out through the modification of the angular components, separated by BRDF model for each spectral band and each pixel. Modeled reflectance values show a good agreement with measured reflectance values and their RMSE(Root Mean Square Error) was totally about 0.01(maximum=0.03). Finally, we provide a normalized surface reflectance database consisted of 36 images for 2001 over Korea.

Estimation of Annual Trends and Environmental Effects on the Racing Records of Jeju Horses (제주마 주파기록에 대한 연도별 추세 및 환경효과 분석)

  • Lee, Jongan;Lee, Soo Hyun;Lee, Jae-Gu;Kim, Nam-Young;Choi, Jae-Young;Shin, Sang-Min;Choi, Jung-Woo;Cho, In-Cheol;Yang, Byoung-Chul
    • Journal of Life Science
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    • v.31 no.9
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    • pp.840-848
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    • 2021
  • This study was conducted to estimate annual trends and the environmental effects in the racing records of Jeju horses. The Korean Racing Authority (KRA) collected 48,645 observations for 2,167 Jeju horses from 2002 to 2019. Racing records were preprocessed to eliminate errors that occur during the data collection. Racing times were adjusted for comparison between race distances. A stepwise Akaike information criterion (AIC) variable selection method was applied to select appropriate environment variables affecting racing records. The annual improvement of the race time was -0.242 seconds. The model with the lowest AIC value was established when variables were selected in the following order: year, budam classification, jockey ranking, trainer ranking, track condition, weather, age, and gender. The most suitable model was constructed when the jockey ranking and age variables were considered as random effects. Our findings have potential for application as basic data when building models for evaluating genetic abilities of Jeju horses.

Effects of Light Color on Energy Expenditure and Behavior in Broiler Chickens

  • Kim, Nara;Lee, Sang-Rak;Lee, Sang-Jin
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.7
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    • pp.1044-1049
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    • 2014
  • This study was conducted in order to investigate whether the presence of light or different colors of light would influence the energy expenditure and behavior of broiler chickens. Eight 8-week-old broiler chickens were adapted to a respiration chamber (Length, 28.5 cm; Height, 38.5 cm; Width, 44.0 cm) for one week prior to the initiation of the experiment. In experiment 1, energy expenditure and behavior of the chickens were analyzed in the presence or absence of light for four days. Chickens were exposed to 6 cycles of 2 h light/2 h dark period per day. In experiment 2, the broiler chickens that had been used in experiment 1 were used to evaluate the effect of 4 different wavelength light-emitting diodes (LEDs) on the energy expenditure and behavior of broiler chickens. The LEDs used in this study had the following wavelength bands; white (control), red (618 to 635 nm), green (515 to 530 nm) and blue (450 to 470 nm). The chickens were randomly exposed to a 2-h LED light in a random and sequential order per day for 3 days. Oxygen consumption and carbon dioxide production of the chickens were recorded using an open-circuit calorimeter system, and energy expenditure was calculated based on the collected data. The behavior of the chickens was analyzed based on following categories i.e., resting, standing, and pecking, and closed-circuit television was used to record these behavioral postures. The analysis of data from experiment 1 showed that the energy expenditure was higher (p<0.001) in chickens under light condition compared with those under dark condition. The chickens spent more time with pecking during a light period, but they frequently exhibited resting during a dark period. Experiment 2 showed that there was no significant difference in terms of energy expenditure and behavior based on the color of light (white, red, green, and blue) to which the chickens were exposed. In conclusion, the energy expenditure and behavior of broiler chickens were found to be strongly affected by the presence of light. On the other hand, there was no discernible difference in their energy expenditure and behavior of broiler chickens exposed to the different LED lights.

Analyzing Perceptions of Small Group Inquiry Activity in the Gifted Education of Korea (한국영재교육에서 소집단 탐구활동에 대한 인식 분석)

  • Jeong, Hyun-Chul;Park, Young-Shin;Hwang, Dong-Jou
    • Journal of the Korean earth science society
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    • v.29 no.2
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    • pp.151-162
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    • 2008
  • This study quantitatively investigated the actual situations and perceptions of gifted students and their teachers during small group inquiry activities in Korea. Some 1,670 gifted math students and 1,732 gifted science students as well as 614 of their teachers were selected through random sampling to participate in this study. Data were collected by means of a survey developed by the researchers of this study, based on reviews of literature related to inquiry and small group cooperative learning. The results were as follows: (1) In Korean gifted education, small group inquiry activities were frequently used as teaching and learning strategies, and both the students and teachers perceived its effects to be very positive in terms of cognition and affection. (2) Gifted education teachers emphasized the development of students' procedural inquiry skills as well as logical thinking skills, whereas they were indifferent to the essential elements of small group cooperative learning and therefore the lessons did not surpass the level of traditional group activities. (3) The fact that the actual small group inquiry activities did not reflect the characteristics of well-organized small group activities is due to a lack of knowledge on the teacher's part as to effective teaching strategies concerning cooperative learning. This study implies that gifted education teachers require the opportunity to reflect on and develop their knowledge and understanding of small group inquiry activities through professionally developed programs in order to maximize the effectiveness of small group inquiry activities in gifted education.

Influence of Joint Distribution of Wave Heights and Periods on Reliability Analysis of Wave Run-up (처오름의 신뢰성 해석에 대한 파고_주기결합분포의 영향)

  • Lee Cheol-Eung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.17 no.3
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    • pp.178-187
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    • 2005
  • A reliability analysis model f3r studying the influence of joint distribution of wave heights and periods on wave un-up is presented in this paper. From the definition of failure mode related to wave run-up, a reliability function may be formulated which can be considered uncertainties of water level. In particular, the reliability analysis model can be directly taken into account statistical properties and distributions of wave periods by considering wave period in the reliability function to be a random variable. Also, variations of wave height distribution conditioned to mean wave periods can be taken into account correctly. By comparison of results of additional reliability analysis using extreme distributions with those resulted from joint distribution of wave height and periods, it is found that probabilities of failure evaluated by the latter is larger than those by the former. Although the freeboard of sloped-breakwater structures can be determined by extreme distribution based on the long-term measurements, it may be necessary to investigate additionally into wave run-up by using the present reliability analysis model formulated to consider joint distribution of a single storm event. In addition, it may be found that the effect of spectral bandwidth parameter on reliability index may be little, but the effect of wave height distribution conditioned to mean wave periods is straightforward. Therefore, it may be confirmed that effects of wave periods on the probability of failure of wave run-up may be taken into account through the conditional distribution of wave heights. Finally, the probabilities of failure with respect to freeboard of sloped-breakwater structures can be estimated by which the rational determination of crest level of sloped-breakwater structures may be possible.

An Empirical Study of Students' Start-Up Activities: Integrated Approach of Student-Focused Cognitive Model and Supportive Activities of University (대학생 창업활동에 대한 실증적 연구 : 대학생 중심의 인지적 모델과 대학지원의 통합적 접근)

  • Chang, Sooduck;Lee, Jaehoon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.4
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    • pp.65-76
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    • 2014
  • The basic purpose of this study is to examine the relationship among entrepreneurial intention, university supports for startup, and startup activities of university students. For the study, we identified the influence factors of students' startup intention based on reviewing preceding studies and examined how these factors affect their intention of new venture startup. In addition, this study attempted to examine how these factors that can have a significant impact on entrepreneurial intention affect startup activities and analyzed how entrepreneurial intention would mediate the relationship between these influence factors and startup activities. A total of 769 students who chosen by random were surveyed and all questionnaires were sent by mail to the universities that entrepreneurship education and entrepreneurial programs were selected as the forerunners from the government. As a result, this study revealed that student's psychological traits such as entrepreneurial self-efficacy and risk-taking have significant effect on the intention of startup. And student's exposure to the role models and various entrepreneurial experiences such as entrepreneurship education and entrepreneurial student's club in the university has significantly positive influence on the intention of startup. This study also found that the effects of these explanatory variables of this research on startup activities have been partially mediated by entrepreneurial intention. The entrepreneurial intention was also proven to have a significant effect on startup activities. Finally, the extent to which university supports activities for students' startup moderated the relationship between entrepreneurial intention and university students' startup activities. We believe that these results of this study contribute to the understanding of the entrepreneurship process both theoretical and practical perspectives.

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High Performance Flexible Inorganic Electronic Systems

  • Park, Gwi-Il;Lee, Geon-Jae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.115-116
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    • 2012
  • The demand for flexible electronic systems such as wearable computers, E-paper, and flexible displays has increased due to their advantages of excellent portability, conformal contact with curved surfaces, light weight, and human friendly interfaces over present rigid electronic systems. This seminar introduces three recent progresses that can extend the application of high performance flexible inorganic electronics. The first part of this seminar will introduce a RRAM with a one transistor-one memristor (1T-1M) arrays on flexible substrates. Flexible memory is an essential part of electronics for data processing, storage, and radio frequency (RF) communication and thus a key element to realize such flexible electronic systems. Although several emerging memory technologies, including resistive switching memory, have been proposed, the cell-to-cell interference issue has to be overcome for flexible and high performance nonvolatile memory applications. The cell-to-cell interference between neighbouring memory cells occurs due to leakage current paths through adjacent low resistance state cells and induces not only unnecessary power consumption but also a misreading problem, a fatal obstacle in memory operation. To fabricate a fully functional flexible memory and prevent these unwanted effects, we integrated high performance flexible single crystal silicon transistors with an amorphous titanium oxide (a-TiO2) based memristor to control the logic state of memory. The $8{\times}8$ NOR type 1T-1M RRAM demonstrated the first random access memory operation on flexible substrates by controlling each memory unit cell independently. The second part of the seminar will discuss the flexible GaN LED on LCP substrates for implantable biosensor. Inorganic III-V light emitting diodes (LEDs) have superior characteristics, such as long-term stability, high efficiency, and strong brightness compared to conventional incandescent lamps and OLED. However, due to the brittle property of bulk inorganic semiconductor materials, III-V LED limits its applications in the field of high performance flexible electronics. This seminar introduces the first flexible and implantable GaN LED on plastic substrates that is transferred from bulk GaN on Si substrates. The superb properties of the flexible GaN thin film in terms of its wide band gap and high efficiency enable the dramatic extension of not only consumer electronic applications but also the biosensing scale. The flexible white LEDs are demonstrated for the feasibility of using a white light source for future flexible BLU devices. Finally a water-resist and a biocompatible PTFE-coated flexible LED biosensor can detect PSA at a detection limit of 1 ng/mL. These results show that the nitride-based flexible LED can be used as the future flexible display technology and a type of implantable LED biosensor for a therapy tool. The final part of this seminar will introduce a highly efficient and printable BaTiO3 thin film nanogenerator on plastic substrates. Energy harvesting technologies converting external biomechanical energy sources (such as heart beat, blood flow, muscle stretching and animal movements) into electrical energy is recently a highly demanding issue in the materials science community. Herein, we describe procedure suitable for generating and printing a lead-free microstructured BaTiO3 thin film nanogenerator on plastic substrates to overcome limitations appeared in conventional flexible ferroelectric devices. Flexible BaTiO3 thin film nanogenerator was fabricated and the piezoelectric properties and mechanically stability of ferroelectric devices were characterized. From the results, we demonstrate the highly efficient and stable performance of BaTiO3 thin film nanogenerator.

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Diagnostic Value of Fluorescence in Situ Hybridization Assay in Malignant Mesothelioma: A Meta-analysis

  • Wan, Chun;Shen, Yong-Chun;Liu, Meng-Qi;Yang, Ting;Wang, Tao;Chen, Lei;Yi, Qun;Wen, Fu-Qiang
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4745-4749
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    • 2012
  • The diagnosis of malignant mesothelioma (MM) remains a clinical challenge and the fluorescence in situ hybridization (FISH) assay has been reported to be one promising tool. The present meta-analysis aimed to establish the overall diagnostic accuracy of FISH for diagnosing MM. After a systematic review of English language studies, the sensitivity, specificity and other measures of accuracy of FISH in the diagnosis of MM were pooled using random-effects models. Summary receiver operating characteristic curves were applied to summarize overall test performance. Nine studies met our inclusion criteria, the pooled sensitivity and specificity for FISH for diagnosing MM being 0.72 (95% CI 0.67-0.76) and 1.00 (95% CI 0.98-1.00), respectively. The positive likelihood ratio was 34.5 (95% CI 14.5-82.10), the negative likelihood ratio was 0.24 (95% CI 0.16-0.36), and the diagnostic odds ratio was 204.9 (95% CI 76.8-546.6), the area under the curve being 0.99. Our data suggest that the FISH assay is likely to be a useful diagnostic tool for confirming MM. However, considering the limited studies and patients included, further large scale studies are needed to confirm these findings.

Stability of suspension bridge catwalks under a wind load

  • Zheng, Shixiong;Liao, Haili;Li, Yongle
    • Wind and Structures
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    • v.10 no.4
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    • pp.367-382
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    • 2007
  • A nonlinear numerical method was developed to assess the stability of suspension bridge catwalks under a wind load. A section model wind tunnel test was used to obtain a catwalk's aerostatic coefficients, from which the displacement-dependent wind loads were subsequently derived. The stability of a suspension bridge catwalk was analyzed on the basis of the geometric nonlinear behavior of the structure. In addition, a full model test was conducted on the catwalk, which spanned 960 m. A comparison of the displacement values between the test and the numerical simulation shows that a numerical method based on a section model test can be used to effectively and accurately evaluate the stability of a catwalk. A case study features the stability of the catwalk of the Runyang Yangtze suspension bridge, the main span of which is 1490 m. Wind can generally attack the structure from any direction. Whenever the wind comes at a yaw angle, there are six wind load components that act on the catwalk. If the yaw angle is equal to zero, the wind is normal to the catwalk (called normal wind) and the six load components are reduced to three components. Three aerostatic coefficients of the catwalk can be obtained through a section model test with traditional test equipment. However, six aerostatic coefficients of the catwalk must be acquired with the aid of special section model test equipment. A nonlinear numerical method was used study the stability of a catwalk under a yaw wind, while taking into account the six components of the displacement-dependent wind load and the geometric nonlinearity of the catwalk. The results show that when wind attacks with a slight yaw angle, the critical velocity that induces static instability of the catwalk may be lower than the critical velocity of normal wind. However, as the yaw angle of the wind becomes larger, the critical velocity increases. In the atmospheric boundary layer, the wind is turbulent and the velocity history is a random time history. The effects of turbulent wind on the stability of a catwalk are also assessed. The wind velocity fields are regarded as stationary Gaussian stochastic processes, which can be simulated by a spectral representation method. A nonlinear finite-element model set forepart and the Newmark integration method was used to calculate the wind-induced buffeting responses. The results confirm that the turbulent character of wind has little influence on the stability of the catwalk.