• Journal of The Korean Association For Science Education
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• v.38 no.4
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• pp.495-504
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• 2018

This study was conducted to develop items to measure scientific core competency based on statements of scientific core competencies presented in the 2015 revised national science curriculum and to identify the validity and reliability of the newly developed items. Based on the explanations of scientific reasoning, scientific inquiry ability, scientific problem-solving ability, scientific communication ability, participation/lifelong learning in science presented in the 2015 revised national science curriculum, 25 items were developed by five science education experts. To explore the validity and reliability of the developed items, data were collected from 11,348 students in elementary, middle, and high schools nationwide. The content validity, substantive validity, the internal structure validity, and generalization validity proposed by Messick (1995) were examined by various statistical tests. The results of the MNSQ analysis showed that there were no nonconformity in the 25 items. The confirmatory factor analysis using the structural equation modeling revealed that the five-factor model was a suitable model. The differential item functioning analyses by gender and school level revealed that the nonconformity DIF value was found in only two out of 175 cases. The results of the multivariate analysis of variance by gender and school level showed significant differences of test scores between schools and genders, and the interaction effect was also significant. The assessment items of science core competency based on the 2015 revised national science curriculum are valid from a psychometric point of view and can be used in the science education field.

• Child Health Nursing Research
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• v.4 no.2
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• pp.159-176
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• 1998

In effort to conduct comparative study on the caregiving environment of Neonatal Intensive Care Unit(NICU) in both U. S and Korea, this study was been conducted first in the U.S. Purpose : The purpose of this study is to identify the physical environment and direct caregiving practices to lowbirth weight infants in NICU in the US. It also aims to examine the NICU outcome status and behavioral reponses of lowbirth weight infants. Methods : A study design using descriptive and inferential statistics was been conducted through an observational, field method. A sample of 15 preform infants admitted to NICU were recruited for the study. The subjects were those with birth weight between 1,000 gm to 1,500 gm, born at the gestation period of 27 to 33 weeks, and without any chromosomal or other genetic anomalies, major congenital infections, or maternal illness. Thirty minutes observation(three times of ten minutes of continuous observation)of the infant's behavior and physiological status, and an four-hour observation of the physical environment and direct care giving procedures were been conducted on the 3rd and 10th day after birth, and on the day of discharge from the NICU or at 34weeks postconception. The data to be collected were in four areas : the demograghic characteristics of the infants, the physical environment and care giving procedures, the frequency of the infant's designated behavior and physiological response, and NICU outcome variables. A descriptive analysis and Kruskal-Wallis, Pearson r were been applied according to variable characteristics. Results : 1. Mother's mean age was 29.47. The sample consisted of 6 males and 9 females. Mean gestational ages were 29.17 weeks. Mean birth weight was 1236.33g. Mean Apgar scores at one minute were 6.6, and 7.8 at five minutes. 2. The location for the incubator was in the distance from the light, X-ray screens and nursing station, in proximity to side-lamp, telephone and faucet on the third day after birth. The location for the incubator was in the distance from the light and radio on the tenth day and in proximity to nursing station on the day of dischage from the NICU or at 34weeks postconception. 3. Nesting was the most applying aids to the infants. And foot roll, shielding and plastic frame were frequently using by nurses for facilitating well modulated restful posture. 4. There were statistically significant changes in the patterns of physical environment included locating the infant's incubator and bedding, specific aids to self regulation on the 3rd and 10th day after birth, and on the day of discharge from the NICU or at 34weeks postconception. 5. Statistically significant changes were not appeared in the patterns of direct caregiving procedure to the infants included stress inducing or reducing manipulations on the 3rd and 10th day after birth, and on the day of discharge from the NICU or at 34weeks postconception. 6. The stress response of the infants in NICU were significantly reduced as the infants grow older. 7. There were not statistically significant correlation between the physical envronment and the stress responses of the infants in NICU. 8. There were statistically significant correlation between the direct caregiving procedure to the infants and the stress response of the infants in NICU in the second and third observation on the day three. 9. Average weight gain per day from birth to discharge was 38.73g, number of days in the hospital was 42.60, number of days before bottle feeding was 3.6. Postconception age starting bottle feed ing was 31/sup +5/ weeks. Number of days on mechanical ventilator was average 7.64, 11.42 was an average number of days of oxygen need. Conclusion : It, thus, appears that to minimize the sensorymotor stimulation for the low birthweight preterm infant in NICU, manipulation of care giving practices to the babies whatever the stress inducing or reducing procedures, have to be limited in the immediate early stage after birth. And it needed to be reexamine to identify the appropriate and specific physical environment and the patterns of direct caregiving to the low birthweight preform infant as the infants grow older in NICU.

• Journal of Radiation Protection and Research
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• v.27 no.1
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• pp.37-49
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• 2002

The accuracy of radiation dose delivery to target volume is one of the most important factors for good local control and less treatment complication. In vivo dosimetry is an essential QA procedure to confirm the radiation dose delivered to the patients. Transmission dose measurement is a useful method of in vivo dosimetry and it's advantages are non-invasiveness, simplicity and no additional efforts needed for dosimetry. In our department, in vivo dosimetry system using measurement of transmission dose was manufactured and algorithms for estimation of transmission dose were developed and tested with phantom in various conditions successfully. This system was applied in clinic to test stability, reproducibility and applicability to daily treatment and the accuracy of the algorithm. Transmission dose measurement was performed over three weeks. To test the reproducibility of this system, X-tay output was measured before daily treatment and then every hour during treatment time in reference condition(field size; $10 cm{\times} 10 cm$, 100 MU). Data of 11 patients whose pelvis were treated more than three times were analyzed. The reproducibility of the dosimetry system was acceptable with variations of measurement during each day and over 3 week period within ${\pm}2.0%$. On anterior- posterior and posterior fields, mean errors were between -5.20% and +2.20% without bone correction and between -0.62% and +3.32% with bone correction. On right and left lateral fields, mean errors were between -10.80% and +3.46% without bone correction and between -0.55% and +3.50% with bone correction. As the results, we could confirm the reproducibility and stability of our dosimetry system and its applicability in daily radiation treatment. We could also find that inhomogeneity correction for bone is essential and the estimated transmission doses are relatively accurate.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.239-246
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• 1995

This research aimed at the contribution to obtaining the scientifical data which were required for planning she environmentally sound and sustainable management, particularly in the field of the logging road construction. Main natural environmental variables including natural vegetation, rainfall, soil runoff were measured in the logging road on-sites and analysed. This project was carried out at the (mt.)Paekunsan Research sorest of Seoul National University, located in Gwangyang, Chollanam-do in southern part of Korea, from 1993 to 1994. 1. The explanatory variables for erosion and sedimentation on logging road surface were accumulated rainfall, erosion distance, cross-sectional gradient, and soil hardness. The erosion and sedimentation on logging road was increasing positively in proportion to the accumulated rainfall, soil distance from starting point of the logging road, and cross-sectional gradient. 2. On cut-slope of logging road, cut-slope shape, part of the slope, plant coverage, soil hardness, sand content, accumulated rainfall, clay content, and silt content were effective factors. Cut-slope erosion and sedimentation on logging roam increased as with the lower plant coverage, the lower accumulated rainfall, the high sand content in the soil. 3. On fill-slope of logging road, there were three significant variables such as total rainfall and number of rainfall-storm. Fill-slope erosion and sedimentation had a positive correlation with the amount of rainfall, the number of rainfall, the soil hardness. 4. The total erosion and sedimentation on logging road were $5.04{\times}10^{-2}m^2/m^2$ in logging road construction year, $7.37{\times}10^{-2}m^2/m^2$ in next year. The erosion and sedimentation on logging road surface were 32.7% of total erosion and sedimentation on Logging road in construction year, and 57.1% in next year, respectively. The erosion and sedimentation on cut-slopes were 30.4% on logging road in construction year, fill-slopes of total erosion and sedimentation and 21.0% in next year, respectively. The erosion and sedimentation on fill-slopes were 36.9% on logging road in construction year, 21.9 in next year. To decrease the erosion and sedimentation at the logging road from the beginning stage of construction, the effective revegetation works should be implemented on the cut-slope and fill slopes, and erosion control measures such as optima. road design must be constructed on read surface.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.293-302
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• 2014

This study was carried out to develop rain shelter which can make an appropriate size and environment for Chinese cabbage rainproof cultivation. Fifty three farms with chinese cabbage rainproof cultivation system have been investigated to set up width and height of rain shelter. Mostly the width of 6m was desired for rain shelter and the height of 1.6m for their eaves, so these values were chosen as the dimensions for rain shelter. After an analysis of their structural safety and installation costs by the specifications of the rafter pipe, Ø$25.4{\times}1.5t$ and 90cm have been set as the size of rafter that such size costs the least. This size is stable with $27m{\cdot}s^{-1}$ of wind velocity and 17cm of snow depth. Therefore it is difficult to apply this dimension to area with higher climate load. In order to sort out such problem, the rain shelter has been designed to avoid damage on frame by opening plastic film to the ridge. Once greenhouse band is loosen by turning the manual switch at the both sides of rain shelter and open button of controller is pushed then switch motor rises up along the guide pipe and plastic film is opened to the ridge. Chinese cabbage can be damaged by insects if rain shelter is opened completely as revealed a field. To prevent this, farmers can install an insect-proof net. Further, the greenhouse can be damaged by typhoon while growing Chinese cabbage therefore the effect of an insect-proof net on structural safety has been analyzed. And then structural safety has been analyzed through using flow-structure interaction method at the wind condition of $40m{\cdot}s^{-1}$. And it assumed that wind applied perpendicular to side of the rain shelter which was covered by insect-proof net. The results indicated that plastic film was directly affected by wind therefore high pressure occurred on the surface. But wind load on insect-proof net was smaller than on plastic film and pressure distribution was also uniform. The results of structural analysis by applying pressure data extracted from flow analysis indicated that the maximum stress occurred at the end of pipe which is the ground part and the value has been 54.6MPa. The allowable stress of pipe in the standard of structural safety must be 215 MPa or more therefore structural safety of this rain shelter is satisfied.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.59-70
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• 2020

This study was proceeded to empirically identify the start-up support policy as an element that affects the performance of the early start-ups and measure the effectiveness of the current start-up support policy, in order to suggest the direction future policies according to the study. To accomplish this the influence of the start-up support policy on the early start-ups was analyzed, and the differences according to the industry and growth stage of the start-ups, as the characteristics of the start-ups, were identified. The research subjects collected real data of 297 start-ups of the past three years that were selected for the Initial Start-Up Package project, and performed multiple regression analysis on the influence between variables, and hierarchical regression analysis on moderating effects. The summary of the study is as follows. First, as a result of identifying the influential relationship between the start-up support policy and the performance of the start-up, sales had made a significant impact on the start-up fund, start-up mentoring, and start-up infrastructure(space), while start-up education failed to show a significant effect on the increase in sales. In terms of employment, start-up mentoring was the only field that showed a significant influential relationship. Second, as a result of identifying the moderating effect of the start-up's industry and growth stage, the industry did not have a statistically significant influence, but the interactive effect was seen in start-up education. To be more specific in terms of the sales relationship of each industry, knowledge services turned out to be helpful in improving sales, while manufacturing turned out to be effective in improving sales regardless of being supported with start-up mentoring and start-up infrastructure (space). The sales relationship regarding the start-up growth stage was identified to be statistically significant. The preliminary stage was not statistically significant, while providing start-up mentoring and start-up funding were effective for start-up stage and growing stage, respectively. On the other hand, employment did not perform a significant influence on the start-up growth stage. This study analyzes the effectiveness the start-up support policy for early start-ups, identifies the need in differentiated support policies according to the characteristics of the start-ups, and suggests implications for the direction in which future policies should be made towards.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.341-347
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• 2015

Purpose : This study was to examine a correlation of response AC/A ratio by additional spherical powers with PD(Pupilary distance) and relative accommodation, and was to investigate correlation of CA/C ratio by prism powers. The mean differences between a reciprocal response AC/A ratio and a CA/C ratio were compared, and were suggested to be used as data in the refractive power and prism prescriptions in the clinical. Methods: The open field autorefractometer (Nvision-K 5001, Shin nippon) and Howell target at 40 cm fixation distance to 62 persons with average $22.62{\pm}2.84$ ages were used to measure the response AC/A ratio according to additional Spherical powers. The CA/C ratios were measured using the DOG card at 40cm according to prism powers. Results: When the response accommodation according to Additional Spherical power changes and the response accommodation according to prism power changes were compared, it was larger than the response accommodation according prism power change. These were significant differences statistically. The correlation of response AC/A ratio and PD is showed as r = -0.158, the CA / C ratio is shown as r = 0.093. The correlation of response AC/A ratio and relative accommodation showed as r = -0.253, the CA/C ratio showed as r = 0.566 that is predictable correlation. The correlation of response AC/A ratio and CA/C ratio showed as r = -0.355 that is low minus correlation (p = 0.000). The difference between a reciprocal response AC/A ratio and a CA/C ratio showed $0.12{\pm}0.06D/{\Delta}$ with a significant difference statistically (p=0.000). Conclusions: The correlation of relative accommodation and CA/C ratio showed that depend on the individual, The more a relative accommodation is, the higher a response accommodation of convergence by convergence stimulus is. The reciprocal response AC/A and CA/C ratio showed significant differences statistically. This can have higher CA/C ratio in patients with low AC/A ratio in clinical as an independent variable. Thus when the abnormal binocular vision was prescribed in the clinical, it is necessary to consider the accommodative response even if the AC/A ratio is a normal range.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.201-219
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• 2014

The Republic of Korea in the real economy to a knowledge economy, and a center of creativity and imagination in the creative economy is changing the paradigm. As the core of creating economic, creative industries with the technology and information play an important role in the industry individuals. In order to solve the problem of the polarization of the economy and high youth unemployment rate of Korea, to recognize the role of the creative industries, as objection part, dimensions pan-national and one creative companies in industries of Mobile Apps various policies that support has been promoted. Support these policies to be able to contribute to the establishment of the success of mobile apps one-person creating company, we performed this study targeting one-person company that creates mobile apps area, we conducted a demonstration study of success factors, and thus more effective and efficient in an attempt to seek out support measures. In this study, we derive a research 4 hypothesis about the success factors of one creative enterprise through literature discussion, a study was made on the basis of empirical data of one-person company that creates mobile apps. The results of the analysis, first, if the development rate of the mobile application technology is fast and a new competition associated product is appeared, it was possible to find a tendency to be higher at the performance quantitative companies. Second, if the founder is a founding for the benefit and rewarding work and come to terms with the risk, it was possible to discover tends to be higher achievement quantitative. Third, if one-person company select a target market with capture intensively, it was possible to find a tendency for higher qualitative results. Fourth, it could be found that the reliability of the contact frequency of the network related performance business environment these characteristics enterprise management strategy and act as a significant modulatory effect. Provision of information relating to management and entrepreneurship education to be one creative enterprise is required, these results suggest that there is a provision continuing need for the opportunity to be able to meet and network and reliable variety have. In this study, to take advantage to promote the elimination measures that can increase the likelihood of success of the company of institutions to support one company that creates knowledge-based, such as in the field of mobile application.

• The Korean Society of Law and Medicine
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• v.18 no.2
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• pp.163-194
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• 2017

Coronary artery disease has increased in Korea as the country enters the aged society. It is well known that the incidence of coronary artery disease is related to aging, hypertension, diabetes, hyperlipidemia, and dietary habit. For effective treatment of significant coronary stenosis, close coordination between cardiac surgery and cardiology team is essential. Especially cardiologists' decision whether to do the stent placement or CABG is very important because the cardiologists usually start to consult the patients for their treatment. Recently, non-surgical interventions(that is stent placement) in cardiology field have dramatically increased as the national insurance system removed the limitation of the number of stents deployed. However, accidents are often caused by inappropriate use of stents, especially in patients with triple coronary disease or left main disease with heavy coronary calcifications. Another aspect of stent placement is to cope with an emergency case in the event of coronary rupture or pericardial tamponade during coronary interventions without cardiac surgeons. In the past two years, the Korea Consumer Agency (Consumer Dispute Coordination Committee) analyzed eight cases of medical dispute settlement. Only two hospitals were manned with both cardiologists and cardiac surgeons. Seven patients died of procedures of stenting and five patients died on the day of the procedure. Among the 8 cases, 5 cases showed 3 vessel disease and the rest of the cases had either severe calcification, complete occlusion or poor coronary antomies for stenting According to a 2017 national data registry of coronary stenting, less than 3 drug-eluting stents were implanted in 98% of all patients. In 2015, the number of stent procedures was 38,922, and approximately in 800 (2%) cases, more than four stents were used per patient. We emphasize that it is necessary to seriously consider the cost-benefit analysis between stent and CABG. The patient has the right to choose the right procedure by asking the liability of 'instruction explanation obligation'. He should be well informed of the pros and cons of both procedures to avoid overuse of stent. It can be solved by intimate discussion of individual cases with the cardiac surgeon and the patient. Unilateral dialogue with the patient, forceful restriction on the number of stenting, lack of surgeon's backup in difficult cases should all be avoided. It is also necessary to solve the problem not only at the hospital level, such as multidisciplinary integrated medical care, but also a nationwide solution such as expanding cardiac surgeons as essential personnel to public officials.

• Investigative Magnetic Resonance Imaging
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• v.18 no.2
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• pp.107-119
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• 2014

Purpose : To efficiently evaluate phased array coil performance using a software tool box with which we can make visual comparison of the sensitivity of every coil element between the real experiment and EM simulation. Materials and Methods: We have developed a $C^{{+}{+}}$- and MATLAB-based software tool called Phased Array Coil Evaluator (PACE). PACE has the following functions: Building 3D models of the coil elements, importing the FDTD simulation results, and visualizing the coil sensitivity of each coil element on the ordinary Cartesian coordinate and the relative coil position coordinate. To build a 3D model of the phased array coil, we used an electromagnetic 3D tracker in a stylus form. After making the 3D model, we imported the 3D model into the FDTD electromagnetic field simulation tool. Results: An accurate comparison between the coil sensitivity simulation and real experiment on the tool box platform has been made through fine matching of the simulation and real experiment with aids of the 3D tracker. In the simulation and experiment, we used a 36-channel helmet-style phased array coil. At the 3D MRI data acquisition using the spoiled gradient echo sequence, we used the uniform cylindrical phantom that had the same geometry as the one in the FDTD simulation. In the tool box, we can conveniently choose the coil element of interest and we can compare the coil sensitivities element-by-element of the phased array coil. Conclusion: We expect the tool box can be greatly used for developing phased array coils of new geometry or for periodic maintenance of phased array coils in a more accurate and consistent manner.