• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.109-125
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• 2004

In recent decades, microscopic simulation models have become powerful tools to analyze traffic flow on highways and to assist the investigation of level of service. The existing microscopic simulation models simulate an individual vehicle's speed based on a constant free-flow speed dominantly specified by users and driver's behavior models reflecting vehicle interactions, such as car following and lane changing. They set a single free-flow speed for a single vehicle on a given link and neglect to consider the effects of highway design elements to it in their internal simulation. Due to this, the existing models are limitted to provide with identical simulation results on both curved and tangent sections of highways. This paper presents a model developed to estimate the change of free-flow speeds based on highway design elements. Nine neural network models were trained based on the field data collected from seven different freeway curve sections and three different locations at each section to capture the percent changes of free-flow speeds: 100 m upstream of the point of curve (PC) and the middle of the curve. The model employing seven highway design elements as its input variables was selected as the best : radius of curve, length of curve, superelevation, the number of lanes, grade variations, and the approaching free-flow speed on 100 m upstream of PC. Tests showed that the free-flow speeds estimated by the proposed model were statistically identical to the ones from the field at 95% confidence level at each three different locations described above. The root mean square errors at the starting and the middle of curve section were 6.68 and 10.06, and the R-squares at these points were 0.77 and 0.65, respectively. It was concluded from the study that the proposed model would be one of the potential tools introducing the effects of highway design elements to free-flow speeds in simulation.

• Journal of Korean Society of Transportation
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• v.28 no.4
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• pp.31-40
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• 2010

The purpose of this study is to formulate an evaluation model and to select evaluation factors for designing scenic roads and designating existing roads as scenic roads. The definition of a "scenic road" contains the purpose not just of travel or access but visiting itself. The value of a scenic road can be enhanced through the preservation of natural environment along the road or the installation of artificial facilities. In order to promote objective scenic road selection and evaluation, the authors used Analytic Hierarchy Process (AHP), which is a multi-criteria decision making method. The weighting value was 0.382 for the value of landscape along the road, 0.154 for the value of landscape in the road, 0.269 for the characteristics of the road, and 0.196 for the management of the road.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.23 no.4
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• pp.391-414
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• 2012

Despite the growth in public concern about health information, the ratio of users who can search for accurate and reliable health information sources has been found to be quite low. Public libraries, as the best contact point to general users, must provide training programs for improving health literacy so that users will have the ability to search and analyze health information, judge the accuracy and reliability of resources, and make informed health-related decisions. This study developed a health information literacy education program suitable for Korean public library users. The effectiveness of the training was measured after administering the program, and necessary improvements were identified. As a result, this study found the education program had the following effects: improved public library users' familiarity with CHI-related terms, improved users' ability to find CHI-related information resources on the Internet, and significantly improved knowledge about health-related websites and information sources. In addition, users expressed interest in seminars on a variety of health information sources in the public library and asked that CHI-related education be included in the library's regular programming. However, this research represented the first time CHI-related education for public library users was performed in Korea, and therefore many limitations were present in the education instructor, the diversity of subjects, and the methodology. Development of more advanced CHI-related education programs for users is still required.

• Korean Journal of Childcare and Education
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• v.7 no.3
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• pp.239-257
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• 2011

The purpose of this study was to redefine and validate the motivational self-concept for child-care teachers. Based on related researches, items were remodified to be good enough to use for studying child-care teachers' motivational self-concept. Redefined items were analysed by factor analysis and validated by use of child-care teachers' professional recognition and their ego-resiliency. Researchers have garnered data from 321 child care teachers as convenience samples who are engaged in child care centers in Seoul and Kyunggi province by using questionnaire research methods. We have eliminated questions that are .40 below communality, questions by conducting exploratory factor analysis. As a result, 6 factors and 23 items were selected; 6 factors have indicated that it explained 77.12% of total variate motivational self-concept rating scale and ${\alpha}$ of Cronbach that of total items indicated acceptable level. After examining relevancy of child-care teachers' professional recognition and ego-resiliency to verify compliant feasibility of the motivational self-concept rating scale, the relation between motivational self-concept and professional recognition was .604(p<0.001) indicating significant static correlation and the relation between motivational self-concept and ego-resiliency was 4.456(p<0.01) indicating significant static correlation. Through this result, it is verified that motivational self-concept rating scale has compliant feasibility in professional recognition and ego-resiliency.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.677-685
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• 2015

In a will to subdue the brittleness as well as the low tensile and flexural strengths of ordinary concrete, researches are being actively watched worldwide on steel fiber-reinforced Ultra High Performance Concrete (UHPC) obtained by admixing steel fibers in ultra high strength concrete. For the purpose of maximizing advantage of UHPC, this study removes the upper flange of the steel girder to apply an inverted T-shape girder for the formation of the composite beam. This paper intends to evaluate the behavior of the shear connectors and the flexural characteristics of the composite beam made of the inverted T-shape girder and UHPC slab using 16 specimens considering the compressive strength of concrete, the mixing ratio of steel fiber, the spacing of shear connectors and the thickness of the slab as variables. In view of the test results, it seemed that the appropriate stud spacing should range between 100 mm and 2 or 4 times the thickness of the slab. Moreover, the relative displacement observed in the specimens showed that ductile behavior was secured to a certain extent with reference to the criteria for ductile behavior suggested in Eurocode-4. The specimens with large stud spacing exhibited larger values than given by the design formula and revealed that the shear connectors developed larger ultimate strength than predicted owing to the action of UHPC and steel after non-composite behavior. Besides, the specimens with narrow stud spacing failed suddenly through compression at the upper chord of UHPC before reaching the full capacity of the shear connectors.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.167-176
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• 2018

Recently, with coming of various channels, the public are communicating with unspecified massive consumers through personal broadcasting. It is becoming more popular as a positive response. The purpose of this study is to investigate the effect of characteristics of personal broadcasting contents on perceived value, perceived value on continuous use intention and the interaction effect of novelty seeking. As a result of verifying the effects of information quality, information trust, and entertainment on the perceived value, the characteristics of personal media contents all showed a significant positive effect and perceived value has a positive effect on continuous use intention. But The interaction effect of novelty seeking and perceived value is not significant. Therefore, content creators should make efforts to create content as much as to the trust of content as entertainment elements in content and composition. In the future, it will be meaningful to proceed with the research on the direct effects of the novelty trend and the various factors affecting viewers' characteristics using personal media contents.

• Journal of IKEEE
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• v.22 no.3
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• pp.858-861
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• 2018

In this paper, we propose the development of a small $360^{\circ}$ oral scanner lens module. The proposed small $360^{\circ}$ oral scanner lens module consists of a small $360^{\circ}$ high resolution(4MegaPixel) lens optical system, a 15mm image sensor unit, and a small $360^{\circ}$ mouth scanner lens external shape. A small $360^{\circ}$ high resolution lens optical system produces a total of nine lenses, the outer diameter of the lens not less than 15mm for use by children through the ages of adulthood. Light drawn by a small $360^{\circ}$ high resolution lens optical system is $90^{\circ}$ flexion so that image images are delivered to image sensors. The 15mm image sensor unit sends the converted value to the ISP(Image Signal Processor) of the embedded board after an image array through the column and the row address of the image sensor. The small $360^{\circ}$ mouth scanner lens outer shape was designed to fix the race to the developed lens. Results from authorized testing agencies to assess the performance of proposed small $360^{\circ}$ oral scanner lens modules, The optical resolving power of $360^{\circ}$ lens was more than 30% at 150 cycles/mm, $360^{\circ}$ lens angle was $360^{\circ}$ in vertical direction, $42^{\circ}{\sim}85^{\circ}$ in vertical direction, and lens distortion rate was 5% or less. It produced the same result as the world's highest level.

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.183-198
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• 2005

The purpose of this study was to develop teaching modules related to Earth Science courses in order to enhance scientific inquiry skills of middle school students. A 'process skill-centered' module was developed to induce scientific process skills, while students explore specific scientific context. A module consists of several activities, and each activity focuses on a specific science process skill. Modules were designed such that the skills would improve depending on the completion of the module. To evaluate the effectiveness, field workshops for middle school science teachers were done twice. Science teachers, who were participants of the workshop, commented that the activities in each module were suited to enhance students' interest in science. They noted that scientific inquiry skills would be developed from each activity. Students responded that the activities in the modules were interesting, and it was a good experience to do them by themselves. Students were the focal point in class, not teachers. This enabled teachers to evaluated each student's achievement level, and provide a proper feedback. Hence, applying these modules in classes should enhance the students' scientific inquiry skills.

• Journal of the Korean earth science society
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• v.26 no.6
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• pp.501-510
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• 2005

An analysis was done on the “inquiry sections” of Earth Science chapters of 10th grade science textbooks. The Inquiry sections were classified into different types and the frequencies of basic process skills, integrated process skills, and inquiry activities were measured in section to find out whether they sufficiently satisfy the requirements based on the 7th National Curriculum. The number of selected science textbooks that have been used in high school for this study were eleven. The number of inquiry tasks were on an average of 24.0. The types of inquiry sections and the elements of basic and integrated process skills were different in every textbooks. The number of inquiry activities were also different and analyzed more than those presented. They were not integrated activities but presented as scientific process skills. The basic process skills and integrated process skills presented in textbooks were $16\%\;and\;77.2\%$, respectively. However, the distribution of two kinds of process skills were analyzed to be $45.6\%\;and\;55.4\%$, respectively. In the process skills, the frequencies of inferring $(49.5\%)$ and data interpretation (68.7%) were the highest; however, the other process skills including recognizing problem, formulating hypothesis and generalization were not even presented in any of the text books. Due to the lack of the definitions of Science process skills and inquiry activities in the 7th National Curriculum, each text book defined these terms differently. It suggests that the meaning of inquiry, science process skills, and inquiry activities should be operationally defined in the national curriculum and the criteria for construction of inquiry activities are required.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.69-78
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• 2004

In this study, the back analysis program was developed by applying the genetic algorithm, one of artificial intelligence fields, to the direct method. The optimization process which has influence on the efficiency of the direct method was modulated with genetic algorithm. On conditions that the displacement computed by forward analysis for a certain rock mass model was the same as the displacement measured at the tunnel section, back analysis was executed to verify the validity of the program. Usefulness of the program was confirmed by comparing relative errors calculated by back analysis, which is carried out under the same rock mass conditions as analysis model of Gens et at (1987), one of back analysis case in the past. We estimated the total displacement occurring by tunnelling with the crown settlement and convergence measured at the working faces in three tunnel sites of Kyungbu Express railway. Those data measured at the working face are used for back analysis as the input data after confidence test. As the results of the back analysis, we comprehended the tendency of tunnel behaviors with comparing the respective deformation characteristics obtained by the measurement at the working face and by back analysis. Also the usefulness and applicability of the back analysis program developed in this study were verified.