• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.277-288
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• 2015

The purpose of this study is to find the point for improvement through the comparative analysis of the 2007 & 2009 revised science curriculum, and the NGSS of the United States with Bloom's revised taxonomy. The results of the analysis confirmed that the revised curriculum in 2009 compared to the revised curriculum in 2007 has expanded the type of cognitive process and knowledge, which promote a higher level thinking. However, the revised curriculum in 2009 has been biased to the type of specific cognitive process and knowledge in cognitive process dimension and knowledge dimension as compared to the NGSS of the United States. In the revised curriculum in 2009, the type of cognitive process such as 'analyze,' 'evaluate,' 'create,' and the type of knowledge such as 'meta-cognitive knowledge' have been treated inattentively. In addition, through comparative analysis, it was identified that the type of cognitive process and knowledge that were neglected in achievement standards were not dealt with in the learning objective of teachers' guides, either. The revised curriculum should consist of achievement standards in comparison to the previous curriculum to reflect better the goals of science education. Therefore, it is necessary to create an achievement standards including various types of cognitive processes and knowledge by improving the method of statement of achievement standards of science curriculum.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.248-257
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• 2005

Statement of problem. Cortical bone plays an important role in the primary implant stability, which is essential to immediate/early loading. However, immediate load-bearing capacity and primary implant stability according to the change of the cortical bone thickness have not been reported. Purpose. The objectives of this study were (1) to measure the immediate load-bearing capacity of implant and primary implant stability according to the change of cortical bone thickness, and (2) to evaluate the correlation between them. Material and methods.48, screw-shaped implants (3.75 mm$\times$7 mm) were placed into bovine rib bone blocks with different upper cortical bone thickness (0-2.5 mm) and resonance frequency (RF) values were measured subsequently. After fastening of healing abutment. implants were subjected to a compressive load until tolerated micromotion threshold known for the osseointegration and load values at threshold were recorded. Thereafter, RF measurement after loading, CT taking and image analysis were performed serially to evaluate the cortical bone quality and quantity. Immediate load-bearing capacity and RF values were analyzed statistically with ANOVA and post-hoc method at 95% confidence level (P<0.05). Regression analysis and correlation test were also performed. Results. Existence and increase of cortical bone thickness increased the immediate load-bearing capacity and RF value (P<0.05) With the result of regression analysis, all parameter's of cortical bone thickness to immediate load-bearing capacity and resonance frequency showed significant positive values (P<0.0001). A significant high correlation was observed between the cortical bone thickness and immediate load-beating capacity (r=0.706, P<0.0001), between the cortical bone thickness and resonance frequency (r=0.753, P<0.0001) and between the immediate load-bearing capacity and resonance frequency (r=0.755, P<0.0001). Conclusion. In summary, cortical bone thickness change affected the immediate load-baring capacity and the RF value. Although RF analysis (RFA) is based on the measurement of implant/bone interfacial stiffness, when the implant is inserted stably, RFA is also considered to reflect implant/bone interfacial strength of immediately after placement from high correlation with the immediate load-baring capacity. RFA and measuring the cortical bone thickness with X-ray before and during surgery could be an effective diagnosis tool for the success of immediate loading of implant.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.3
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• pp.362-374
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• 2007

Statement of problem. The intial stability for osseointegration of implant has been an interesting factor. Especially, in the case of poor bone quality or immediately loaded implant, various strategies have been developed focusing on the surface of materials to improve implant fixation to bone. The microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Purpose. The aims of this study are to perform a histologic and histomorphometric comparison of the healing characteristics of three different surfaces and the comparison of resonance frequency analysis (RFA) values measured by $Osstell^{TM}$ and perio-test values (PTV) measured by Periotest. Material and methods. A total of 24 screw titanium implants (Dentium Co., Seoul, Korea) with 6mm in length and 3.4mm in diameter, were placed in the mandible of 4 beagle dogs. Implants were divided into three groups following the surface treatment methods: Group I is machined(control group). Group II is anodically oxidized. Group III is coated 500nm in thickness with hydroxyapatite(HA) by ion beam assisted deposition(IBAD) on the anodized oxidization. Bone blocks from 2 dogs were caught after 3 weeks of covered healing and another blocks from 2 dogs after 6 weeks. RFA values and PTV were measured right after insertion and at 3 and 6weeks. Histomorphometric analysis was made with Kappa Image Base System to calculate bone-to-implant contact (BIC) and bone area inside the threads. Pearson's correlation analyses were performed to evaluate the correlation between RFA and PTV, BIC and bone area ratio of three different surfaces at 3 and 6 weeks. Results. 1) In all surface treatment methods, the RFA values decreased and the PTV values increased until 6 weeks in comparison to initial values. 2) At 3 weeks, no significant difference was found from bone-to-implant contact ratio and bone area ratio of three different surface treatment methods(P>0.05). However, at 6 weeks, different surface treatment methods showed significantly different bone-toimplant contact ratio and bone area ratio(P<0.05). 3) In the implants with the IBAD on the anodic oxidization, significant difference was found between the 3 weeks and the 6 weeks bone area ratio(P<0.05). 4) Correlation was found between the RFA values and the bone area ratio at 3 and 6 weeks with significant difference(P<0.05). Conclusions. These results indicate that the implants with the IBAD on the anodic oxidization may have a high influence on the initial stability of implant.

• Journal of the Korean earth science society
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• v.29 no.4
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• pp.341-351
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• 2008

The purpose of this study was to investigate eighth graders' scientific method of inquiry used in their reports. We developed a framework, 'Analysis of Scientific Methods and Information Sources', with a perspective of the Nature of Science to analyze students' planning method, data analysis, and information sources. We then compared results with levels of questions to find out whether they affected students' 'Scientific Method'. In addition, we analyzed students' responses of the survey questionnaire, e.g.. how they liked Scientific Method. Results are as follows: First, 'planning method' consisted of 'consultant' and 'activities'. The 'activities' were 'experiment', 'correlational study', and 'observation' Students planned by utilizing 'consultant' more than the other. In case of planning 'activities'. most of them were 'experiment' Second, 'data analysis' consisted of 'summary', 'table', 'chart', 'graph' and so on. Students analyzed their data by using 'summary' frequently. The types of 'summary' were divided into 'simple summary' and 'relational statement' Third, 'information sources' consisted of 'computer', 'library'. and 'professional consultant' Most of the students gathered information from 'computer' Fourth, the types of 'planning method' and 'summary' were affected by the levels of questions. Fifth, some of the students reported their difficulty in 'planning method' because the collected information was less reliable, lacking, and having difficult technical terms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3022-3029
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• 2011

One of the characteristics of the informatics subject implementing the revised national curriculum is to develop the practical attitude of the student as an active member of information society. The purpose of this study is to examine whether the units 'Information Society and IT' in middle school informatics textbooks reflect inquisitive tendencies to student's practice. After four textbooks that were widely selected by schools were selected from among the authorized textbooks, the sentences of the selected textbooks were analyzed by utilizing Romey's analysis method to see whether there was such an inquisitive tendency in them. As a result of analyzing six content elements of the textbooks, one textbook and two textbooks had an inquisitive tendency in three elements or more in terms of texts and activities index respectively. But there was no inquisitive tendency in the textbooks in terms of figure/diagrams, questions at the end of chapters and chapter synthesis. This study is meaningful in that it attempted to make a quantitative analysis of middle school informatics textbooks and to investigate an inquisitive tendency in the textbooks by analyzing every statement and sentence instead of analyzing just some parts of the textbooks.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.79-92
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• 2019

This study analyzes the effects of freight transportation income, capital, asset, non-operating expenses, and debt ratio on the debts of inner port freight transportation businesses through the GLS of panel regression analysis and the estimation of fixed effects model. The factors and hypotheses were established through a theoretical background review, and the financial statement and profit and loss data of inner port freight transportation businesses for 10 years from 2006 to 2015 were analyzed. The results showed that assets had positive effects on debts, and negative effects on capital, non-operating expenses, and debt ratio, but no effect on freight transportation income. This result empirically demonstrates the tendency of inner port freight transportation businesses to secure assets by increasing debts, creation of debt reduction leverage effect using non-operating expenses such as interest expenses through bank borrowing, and the adoption of management characteristics and financial operation method to lower the debt ratio by reducing capital more than debts. In future studies, it is necessary to analyze coastal port freight transportation business by industry (oil tankers, cargo ships, and barge ships), and regions such as East, West and South sea.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.340-350
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• 2021

This study was conducted by utilizing the Q research method, which is one of the qualitative analysis methods that can approach the in-depth and essential meaning of consumers' restaurant O2O service operation behavior. The purpose of this study is to classify the behavior of restaurant O2O services by type, to find out the characteristics of variables, and to suggest future improvement directions. An exploratory study was conducted using the Q-methodology to analyze the subjective perception of the restaurant O2O service behavior. To this end, positive and negative statement cards were prepared, P samples were selected, and Q-sort, which was subjected to classification, was analyzed using the PC QUANL program and Q factor analysis. As a result of the analysis, it was classified into three single types. Type 1 【(N= 7: Restaurant O2O Service Convenience Syndrome Type】, Type 2 【(N= 7): Restaurant O2O Service Benefit Pursuit Type】, Type 3 【(N= 6): Restaurant O2O Service Convenience Type】 The name of the factor was set as [Type], and it was found that each type has different characteristics. Through this analysis, the marketing strategy according to each factor detected is presented, and the point of supplementing the restaurant's O2O service and the direction of future operation. services in future studies.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.4
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• pp.393-404
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• 2003

Statement of problem. Higher incidence of prosthetic complications such as screw loosening, screw fracture has been reported for posterior single tooth implant. So, there is ongoing research regarding stability of implant-abutment interface. One of those research is increasing the implant diameter and prosthetic table width to improve joint stability. In another part of this research, internal conical type implant-abutment interface was developed and reported joint strength is higher than traditional external hex interface. Purpose. The purpose of this study is to compare stress distribution in single molar implant between external hex butt joint implant and internal conical joint implant when increasing the implant diameter and prosthetic table width : 4mm diameter, 5mm diameter, 5mm diameter/6mm prosthetic table width. Material and method. Non-linear finite element models were created and the 3-dimensional finite element analysis was performed to see the distribution of stress when 300N static loading was applied to model at $0^{\circ},\;15^{\circ},\;30^{\circ}$ off-axis angle. Results. The following results were obtained : 1. Internal conical joint showed lower tensile stress value than that of external hex butt joint. 2. When off-axis loading was applied, internal conical joint showed more effective stress distribution than external hex butt joint. 3. External hex butt joint showed lower tensile stress value when the implant diameter was increased. 4. Internal conical joint showed lower tensile stress value than external hex butt joint when the implant diameter was increased. 5. Both of these joint mechanism showed lower tensile stress value when the prosthetic table width was increased. Conclusion. Internal conical joint showed more effective stress distribution than external hex joint. Increasing implant diameter showed more effective stress distribution than increasing prosthetic table width.

• Journal of The Korean Association of Information Education
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• v.19 no.3
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• pp.311-322
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• 2015

This study analyzed the trend and problems in the design of contents developed by teachers, and suggested strategies for improvement. It analyzed the contents ranked as the first level in the Research Competition on Educational Informatization for the last 3 years. Concerning the 8 types of instructional activities and the 6 types of knowledge acquisition, most contents took limited types(i.e., the individual tutoring type, the concept learning type and the principle learning type). In addition, when the contents were evaluated according to the quality certification criteria for educational software, it was found that the quality level of the design was low in many criteria. When the content analysis was applied for the in-depth analysis of design characteristics, various problems were found in the areas such as evaluation, feedback and learning objectives. Also other common problems were found in the design areas such as level-based differentiated learning, interaction between students and contents, presentation of text and narration, utilization of information on a student, screen design, the content level appropriate for students. In relation to the problems found from the analysis, some strategies for improvement were suggested concerning the following topics: question selection and guidance for evaluation, content and types of feedback, statement of learning objectives, selection of content, interaction, and screen design.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.5
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• pp.582-595
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• 2003

Statement of problem : Most posts are metallic, but in response to the need for a post that possesses optical properties compatible with an all-ceramic crown. an esthetic post has been developed. Although there have been many studies about the esthetic post materials, 3-dimensional finite element studies about the stress distribution of them are in rare. Purpose : The purpose of this study is to investigate comparatively the distribution of stresses of the restored, endodontically treated maxillary incisors with the esthetic post materials and the displacement on the cement layer on simulated occlusal loading by using a 3-dimensional finite element analysis model. Material and method : Four 3-dimensional finite element models were constructed in a view of a maxillary central incisor, a post, a core, and the supporting tissues to investigate the stresses in various esthetic posts and cores and the displacement on the cement layer (Model 1 ; Cast gold post and core, Model 2 ; Glass fiber post with composite core, Model 3 ; Zirconia post with composite core. Model 4 ; Zirconia post with ceramic core). Force of 300N was applied to the incisal edge and the cingulum (centric stop point) with the angle of 135-degree to the long axis of the tooth. Results : 1. The stresses and displacement on the incisal edge were higher than on the cingulum 2. The stresses in dentin were the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. 3. The stresses in post and core were the highest in Model 4 (Zirconia post with ceramic core), and the second was Model 1, the third Model 3, and the lowest Model 2. 4. The displacement on the cement layer was the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. Conclusion : When a functional maximum bite force was applied, the distribution of stresses or the esthetic post and core materials and the displacement on the cement layer were a little different. It seems that restoring extensively damaged incisors with esthetic post and core materials would be decided according to the remaining tooth structure.