• Journal of Biosystems Engineering
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• v.27 no.2
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• pp.117-124
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• 2002

This research was conducted to develop a method to remove the effect of surface temperature of Shingo pears for sugar content measurement. Sugar content was measured by a near-infrared spectrum analysis technique. Reflected spectrum and sugar content of a pear were used for developing regression models. For the model development, reflected spectrums having wavelengths in the range of 654 to 1,052nm were used. To remove the effect of surface temperature, special sample preparation techniques and partial least square (PLS) regression models were proposed and tested. 71 Shingo pears stored in a cold storage, which had 2$^{\circ}C$ inside temperature, were taken out and left in a room temperature for a while. Temperature and reflected spectrum of each pear was measured. To increase the temperature distribution of samples, temperature and reflected spectrum of each pear was measured four times with one hour twenty minutes interval. During the experiment, temperature of pears increased up to 17 $^{\circ}C$. The total number of measured spectrum was 284. Three groups of spectrum data were formed according to temperature distribution. First group had surface temperature of 14$^{\circ}C$ and total number of 51. Second group consisted of the first and the fourth experiment data which contained the minimum and the maximum temperatures. Third group consisted of 155 data with normal temperature-distribution. The rest data set were used for model evaluation. Results shelved that PLS model I, which was developed by using the first data group, was inadequate for measuring sugar content of pears which had different surface temperatures from 14$^{\circ}C$. After temperature compensation, sugar content predictions became close to the measured values. Since using many data which had wide range of surface temperatures, PLS model II and III were able to predict sugar content of pears without additional temperature compensation. PLS model IV, which included the surface temperatures as an independent variable. showed slightly improved performance(R$^2$=0.73). Performance of the model could be enhanced by using samples with more wide range of temperatures and sugar contents.

• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.1-16
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• 2000

It is difficult to treat the endodontic apical perforation successfully. In this study, we hypothesized that the application of PDGF-BB and IGF-I into periapical perforation site may accelerate periapical healing and lead to bone deposition. And the specificity of osteonectin in periapical healing was investigated. The experiments were performed on the upper and lower 51 premolar teeth of 4 beagle dogs. The pulp chamber of each tooth was opened and the dental plaque was inserted into the canal for developing the periapical lesion for 5 weeks. Then, the roots were artificially perforated at the apex with the number 4 profile of .06 taper. In each step, standard periapical radiographs were taken to compare the size of lesion each other. The radiographs were scanned and analyzed by image analysis system. The mean and standard deviation of periradicular radiolucency ratios were calculated in each group. ANOVA was used for comparison. 51 premolars were grouped into 3 groups; control group, calcium hydroxide-treated group and calcium hydroxide plus growth factors-treated group. In the control group, the apical perforations were not sealed and obturated with gutta-percha and ZOE sealer by lateral condensation technique. In the experimental groups, the apical perforation were sealed with calcium hydroxide and with/without $4{\mu}g$ of PDGF-BB & IGF-I in cellulose gel and obturated by lateral condensation technique. Fluorescent bone markers were used to measure new bone formation. Following 2, 4, 12 weeks after experiment the dogs were sacrificed and histologic sections were prepared. Each tooth block including periapical lesion was sectioned mesiodistally. One half of the sections were decalcified with 6% nitric acid and processed by standard paraffin embedding technique. The sections were stained by hematoxylin and eosin, and immunostained for osteonectin. Histomorphometrical measurement of neoformed bone was performed using a light microscope. And the other half of the sections were prepared by undecalcified preparation, and confocal laser scanning microscopic investigations were done.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.35-39
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• 1998

We analyzed image factors to determine the characteristic factors that need for intelligent replenishment system of the auto film processor. We processed the serial 300 sheets of radiographic films of chest phantom without replenishment of developing and fixation replenisher. We took the digital data by using film digitizer which scaned the films and automatically summed up the pixel values of the films. We analyzed characteristic curves, average gradients and relative speeds of individual film using densitometer and step densitometry. We also evaluated the pH of developer, fixer, and washer fluid with digital pH meter. Fixer residual rate and washing effect were measured by densitometer using the reagent methods. There was no significant reduction of the digital density numbers of the serial films without replenishment of developer and fixer. The average gradients were gradually decreased by 0.02 and relative speeds were also gradually decreased by 6.96% relative to initial standard step-densitometric measurement. The pHs of developer and fixer were reflected the inactivation of each fluid. The fixer residual rates and washing effects after processing each 25 sheets of films were in the normal range. We suggest that the digital data are not reliable due to limitation of the hardware and software of the film digitizer. We conclude that average gradient and relative speed which mean the film's contrast and sensitivity respectively are reliable factors for determining the need for the replenishment of the auto film processor. We need more study of simpler equations and programming for more intelligent replenishment system of the auto film processor.

• The Korean Journal of Applied Statistics
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• v.29 no.4
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• pp.595-611
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• 2016

We use nonlinear regression models (such as the Hill Model) when we analyze data in toxicology and/or pharmacology. In nonlinear regression models an estimator of parameters and estimation of measurement about uncertainty of the estimator are influenced by the variance structure of the error. Thus, estimation methods should be different depending on whether the data are homoscedastic or heteroscedastic. However, we do not know the variance structure of the error until we actually analyze the data. Therefore, developing estimation methods robust to the variance structure of the error is an important problem. In this paper we propose a method to estimate parameters in nonlinear regression models based on a preliminary test. We define an estimator which uses either the ordinary least square estimation method or the iterative weighted least square estimation method according to the results of a simple preliminary test for the equality of the error variance. The performance of the proposed estimator is compared to those of existing estimators by simulation studies. We also compare estimation methods using real data obtained from the National Toxicology program of the United States.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.37-46
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• 2012

The number of traffic accidents caused by elderly drivers over the age of 65 has surged over the past ten years from 37,000 to 274,000 cases. The proportion of elderly drivers' accidents has jumped 3.1 times from 1.2% to 3.7% out of all traffic accidents, and traffic safety organizations are pursuing diverse measures to address the situation. Above all, connecting safety measures with an in-depth research on behavioral and physical characteristics of elderly drivers will prove vital. This study conducted an empirical research linking the driving characteristics and traffic accidents by elderly drivers based on the Driving Aptitude Test items and traffic accident data, which enabled the measurement of behavioral characteristics of elderly drivers. In developing the Influence Model, we applied the zero-inflated Poisson (ZIP) regression model and selected an accident prediction model based on the Bayesian Influence in regards to the ZIP regression model and the zero-inflated negative binomial (ZINB) regression model. According to the results of the AAE analysis, the ZIP regression model was more appropriate and it was found that three variables? prediction of velocity, diversion, and cognitive ability? had a relation of influence with traffic accidents caused by elderly drivers.

• Journal of Gifted/Talented Education
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• v.20 no.3
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• pp.921-946
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• 2010

The purpose of this study is to devise a model of career decision in the science-gifted by exploring factors of having influence upon career decision in the science-gifted undergraduates of our country, and by examining pattern and path of career decision. By suggesting a model of structure, which synthetically considered factors of parents (parental social support), school (stress of college life, adjustment to college life), and individual characteristics(problem solving ability, career decision-making self-efficacy, conviction for major selection)as for career decision in the science-gifted undergraduates through this study, the aim was to arrange the theoretical frame for career in the science-gifted undergraduates. The research subjects were 93(class of 2007~2009) students who completed education in 2002 and 2003 at the gifted education center affiliated with University, and 264 scholarship students(class of 2005-2008) by the President at home and abroad, who are receiving scholarship by being selected as a science scholarship student by the incumbent President. The measurement tools, which were used in this study for collecting data, are test of parental social support, test of problem-solving ability, test of stress in college life, test of adjustment to college life, test of efficacy in career decision, and test of having confidence in selecting a major. For statistical analysis of the collected data, SPSS Program and AMOS Program were used. As a result, the model showed a good fit to the present data in the science-gifted undergraduates, TLI=.928, CFI=.941, RMSEA=.059. It was confirmed to be a model that is accepted in the group of the science-gifted undergraduates. Also, hypotheses, which were established on the basis of a theoretical quest, could be known to have been all adopted except one path. The results of this study can be offered as basic data for developing program and implementing a system in order to broaden the width of understanding about career and to help the career decision in the science-gifted.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.139-146
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• 2016

The purpose of this study is to investigate the necessity of safety awareness and education regarding the use of laboratories, and to foster safety awareness during intramural and extracurricular activities in high schools. The study conducted a questionnaire to 290 eleventh grade students of three high schools located in Seoul. The collected data were statistically analyzed. The result illustrates that 64.8% of students have experienced safety education during a regular class, 6.6% have experienced accidents, and 68.0% have experienced safety education during field activities. The result concludes that there is a lack of prior safety education as well as overall low awareness on the necessity of safety education. In particular, students who have experienced safety education recognizes the necessity of emergency education regarding laboratory accident more than those who did not receive such education. Thus, a systematic management of laboratory safety education and multilateral management measures for students' safety are required. There is a relatively high correlation between safety intention of R&D and Education factors and Community and Laboratory Safety Education. As much as there is a high safety demand regarding the laboratory instruments and experiment, it shows high intention of safety lab operation as well as count measurement of lab accident. This study recommends developing a laboratory safety education program and management methods appropriate for high school students.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.304-310
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• 2017

This study is a methodological research study that tests the validity and reliability of the NCRC (Nurse Clinical Reasoning Competence scale), an instrument developed by Liou and his colleagues as the basic data for enhancing the clinical reasoning competence of nurses, by translating it into Korean and checking the similarity of the sentence structure and meaning (between the two versions?). This study verified its validity and reliability by examining 166 nurses working in four tertiary hospitals located in Seoul and Busan. An analysis of the content validity by experts showed that all of the items have a content validity higher than CVI 0.8. From the exploratory and confirmatory factor analysis, it was found that the instrument includes a total of 15 items consisting of one factor. In addition, the correlation with the Korean version of the Nurse Clinical Reasoning Competence scale is confirmed to test the concurrent validity, by using a measurement tool of nurses' critical thinking dispositions and clinical decision-making abilities (correlation coefficient =.55-.64(p<.001) and Cronbach's ${\alpha}=.93$). Thus, the Korean version of the NCRC may be a useful instrument for evaluating the clinical reasoning competence of Korean nurses and providing the basic data for assessing their clinical reasoning competence and developing their promotion strategies.

• 재활복지
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• v.21 no.1
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• pp.253-277
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• 2017

The purpose of this study was to develop the Constraints in Physical Activity Scale for people with physical Disabilities(CPASD) which measures the constraints in physical activity of people with physical disabilities. For this study, the 5 step analytic framework of unified validity developed by Messick (1995), the framework for conducting a strong program of construct validation by Benson (1998) method were applied. Furthermore, the validity of CPASD was systematically presented by applying common factor model and measurement model to 264 persons with physical disabilities. The conclusion based on the results and discussions of this study is as follows. First, CPASD presented evidence of job validity. Four factors (17 items) were developed, consisting of leader constraints, economic constraints, prejudice, and exercise environment constraints through the analysis of the factor structure and the fit of factor coefficients. Second, the factor structure of the developed CPASD (leader constraint, economic constraint, prejudice, exercise environment constraint) was statistically distinguished and stably reflected the existing exercise participation constraints theory. Third, the developed CPASD presented evidence of the validity of the criteria. Leader constraints and prejudice were negatively correlated with positive motor emotions, leader constraints, prejudice, and exercise environment constraints were positively correlated with negative motor emotions. Therefore, in future research, it is necessary to reevaluate the current system and actual condition related to leader constraints, economic constraints, prejudices, and exercise environment constraints derived as factors of CPASD. To do this, it is necessary to judge the degree of reality based on the causal relationship verification and IRT theory using CPASD.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.228-228
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• 2015

Water reuse plays significant role in water saving and water environmental protection, and it helps alleviate the shortage of water resources. China's water reuse was put into practice since 1980s by means of pilot and promotion in National Fifth-year Plan and other strategies. The effects of water reuse is beneficial in both economic, social and environmental aspects. But some shortcomings still undermine future development of water reuse in China. To overcome and boost water reuse, Ministry of Water Resources conducted a successive survey across China. The aim of this study is to demonstrate the current condition of water reuse in China in construction, funds, legislation, planning, policy aspects, to summarize problems and its reasons underneath, to make suggestions for further development. Basically, in 2010, China's water reuse is 2.83 billion cubic meters and the utilization rate is 10.35%. Water reuse in China has four major characteristics: the first one is water reuse differences in amount occur national-widely and North of China has the main percentage as 47.3%; the second one is water reuse is mainly in environment maintenance (42.1%) and industry cooling (29.8%); the third one is funds for water reuse station and pipe construction is main in non-fiscal budget which take percentage as 56.8%; the fourth one is progresses of administrative system, political system, price management, standard system and technologies go rapidly recently. The problems of water reuse such as lack in water reuse station, delay in pipe constriction and limits on water reuse amount still exist due to some reasons. As a think tank of Ministry of Water Resources, we give some suggestions: firstly, water reuse needs to be integrated with traditional water resources allocation; secondly, public budgets need to be strengthened and income mechanism should also be constructed; thirdly, water resources integrated administrative of city and county should be boosted and roles as water reuse need to be clear and precise; fourthly, national, provincial and regional water reuse planning should be made in time; fifthly, regulations on water reuse should be programmed as soon as possible.