• Journal of the Korean Society for Precision Engineering
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• v.29 no.12
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• pp.1346-1350
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• 2012

Contact wire is one of the most important components supplying electricity to railroad cars. At the beginning of the research on contact wire, wear problem caused by friction between contact wire and pantograph was considered even more important issue for the failure of contact wire. However, since several fatigue fractures were reported from Shinkansen in Japan, fatigue fracture has become another important issue for the failure of contact wire. Despite of its importance, standard of the fatigue test of contact wire has not been established yet. Thus, fatigue characteristics of contact wire is very difficult issue to evaluate quantitatively. Hence, in this study, test method simulating operating conditions of contact wire by Minsung Kang and etc. is used to evaluate the fatigue characteristics of copper alloy contact wire. Also, test results is compared with the result of Minsung Kang's research on pure copper contact wire.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.2
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• pp.149-159
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• 2016

In this study, the solitary wave-induced tsunami force acting on an onshore bridges in coastal area was numerically modelled by means of TWOPM-3D based on Navier-Stokes solver and VOF method which can track free surface effectively. The validity of numerical analysis was verified by comparing the experimental tsunami bore force acting on vertical wall and column structure. In particular, the characteristics of tsunami force with the changing tsunami intensity were surveyed through numerical experiments. The availability of 3-dimensional numerical analysis was reviewed through the comparison between the existing numerical results and design criteria for each drag force coefficient by applying Morison equation considering only drag force. As reasonable and high-precision estimation method of tsunami force, it was suggested to apply the estimation method taking drag and inertial force into consideration at the same time.

• Journal of the Korean Dietetic Association
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• v.7 no.1
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• pp.72-79
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• 2001

The purpose of this study is to investigate the dietary intakes and nutritional status in total gastrectomized patients. We assessed the nutritional status by dietary intake, anthropometric data and biochemical data. And we also checked the subjective postprandial symptoms and gastrofiberscopy to detect the reflux esophagitis in 22 patients who were free of tumors for more than 1 year after total gastrectomy by the three different reconstruction methods(Loop esophagojejunostomy with A-loop tie/ Roux-en-Y esophagojejunostomy/Roux-en-Y esophagojejunostomy with Paulino pouch). Any patients were not in malnutrition status in respect to biochemical data. By assessing the dietary intake, the average daily calorie intake was 1848.2$\pm$440.2kcal, it was 105.9$\pm$23.8% of energy requirement. But there was weight loss in 21 patients of 22 patients after operation and the weight loss was 12.8% of preoperative weight(61.0$\pm$7.9 vs. 53.5$\pm$6.7kg, preoperatively vs. at the time of study). This may suggest that continuous nutritional care is necessary after total gastrectomy to promote sufficient calorie intake, keeping good nutritional state. There were no significant differences between the methods of reconstruction and dietary intakes or nutritional status. Endoscopic esophagitis was more frequently found in patients of loop esophagojejunostomy than any other reconstruction methods(p<0.001), but it didn't show any effect on the dietary intakes.

• Journal of Agricultural Extension & Community Development
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• v.16 no.4
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• pp.869-912
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• 2009

The objective of this study is to promote alternative plans on the prejudiced and distorted contents in school textbooks in the aspect of multi-functionality of agriculture and rural community. This was done through analysis of contents in 47 kinds of textbooks in science (8 of elementary school, 27 of middle school and 12 of high school). This will lead to promote understanding about the multi-functionality and form the proper value system related to agriculture and rural community for children and juveniles using textbooks. A content analysis was employed to examine to what extent the contents on agriculture and rural community were reflected in the textbooks for elementary school, middle school and high school. The content analysis was done in three categories, including presentation form, application method and function view. The followings are results of contents analysis in textbooks. The most frequently used presentation forms related to agriculture and rural community was figures and tables. In analysis of application methods, this research found that the contents related to agriculture and rural community were used to explain scientific facts and phenomena. In the function view, maintenance of local societies was most frequent among the various multi-functionalities in elementary and middle school, and food security in high school. Based on the results of content analysis, findings and recommendations in textbooks for elementary, middle and high school have been drawn, and several examples for contents development to be included in the textbooks were listed.

• Imaging Science in Dentistry
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• v.47 no.2
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• pp.87-92
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• 2017

Purpose: The aim of this study was to determine whether the panoramic mandibular index (PMI) is useful for assessing bone mineral density. We also analyzed the potential correlations between PMI parameters and patient age. Materials and Methods: Four observers measured the PMI of both sides of the mental foramen using a picture archiving and communication system and images in the Digital Imaging and Communications in Medicine format. They studied 300 panoramic radiographic images of patients belonging to the following age groups: 40-49 years, 50-59 years, 60-69 years, 70-79 years, and 80-89 years. The observers were allowed to zoom in or out and to adjust the contrast of the images. Further, they were instructed to record the reasons for any measurements that could not be made. Then, we conducted a reliability analysis of the measured PMI and assessed the correlations between different patient age groups and the 3 parameters used for determining the PMI from the available data. Results: Among the 600 data items collected, 23 items were considered unmeasurable by at least 1 observer for the following 4 reasons: postoperative state, lesion, unidentified mental foramen, and alveolar bone loss. The intraobserver reproducibility of the measurable data was 0.611-0.752. The mandibular cortical width (MCW) decreased significantly as patient age increased. Conclusion: PMI had limited usability when the margin of the mental foramen was not clear. In contrast, MCW, a parameter used for determining the PMI, had fewer drawbacks than the PMI with respect to bone mineral density measurements and exhibited a significant correlation with patient age.

• Journal of Fisheries and Marine Sciences Education
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• v.12 no.2
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• pp.152-163
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• 2000

Floating resin pellets including plastics were surveyed from 7 coastal beaches near Young-il Bay during summer and winter season on 1998 ~ 2000 year. Plastic fabrication materials in the survey were founded with 6 items using the following; resin pellets, plastic debris, styrofoams, cigar filters, wood pieces and charcoals. The results deduced in the areas are as follows: 1. The seasonal variability of the all debris is revealed that summer season were remarkably larger than those of winter. This is deduced it is attributed to meteorological effects, e.g, the seasonal wind strength, current vectors and resorts of crowded people for beach enjoy. And the distribution of plastic debris is Pohang Songdo $12.9ea/m^2$, Pohang Bookbu $8.8ea/m^2$, Togoo $4.9ea/m^2$, Chilpo $3.2ea/m^2$, Hwajin $1.4ea/m^2$, Wolpo and Guryongpo $0.8ea/m^2$ respectively. 2. Compared with each beaches, Songdo beach, northern part beach of Pohang city and Togoo beach have higher densities than those of the others. Especially, the highest densities of all debris were discovered in the Songdo beach of Pohang city. 3. The change of density over the whole year was similarly distributed in quantities and fabrication materials. 4. These surveys were founded that the most parts of plastic debris materials were made up with PE and PP.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.108-116
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• 2017

In this study, the prototype structure of seismically designed steel moment frame was analyzed statically and dynamically in order to demonstrate the applicability of energy-based approximate analysis with the dynamic effect of sudden column loss in the evaluation of the collapse resistance and a method for assessing the sensitivity to progressive collapse was proposed. For the purpose of comparing the structural behavior of buildings with different structural systems, the sensitivity of the structure to the sudden removal of vertical members can be used as a significant measure. The energy-based approximate analysis prediction for the prototype structure considered in the study showed good agreement with the dynamic analysis result. In the sensitivity evaluation, the structural robustness index that indicates the ability of a structure to resist collapse induced by abnormal loads was used. It was confirmed that the proposed methods can be used conveniently and rationally in progressive collapse analysis and design.

• Journal of Cadastre & Land InformatiX
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• v.45 no.2
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• pp.45-56
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• 2015

The main purpose of this investigation is to make up for the limitations of parcel addressing and to seek the application plan of cadastral triangulation point to effective installation of national index numbers. The test-bed has been constructed at the mountainous area located in Nowon-gu, seven cadastral triangulation points within the test-bed was directly applied to this investigation. Each points have been firstly converted from a plane rectangular coordinates to a single plane rectangular coordinates (UTM-K). To verify positioning results achieved from these points, a single plane rectangular coordinates through the Network-RTK was considered. With regards to verification result, maximum coordinate shift was revealed by 6 cm, this level of difference can be satisfied to Article 7, paragraph 2 "the regulation for National Index Number". This means that coordinate transformation applied with cadastral triangulation points can achieve the sastisfied result without local surveying. And also, remarkable effects have been created in terms of financial effectiveness and safe preservation of cadastral triangulation points due to the omission of local surveying.

• Korean Journal of Microbiology
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• v.34 no.1_2
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• pp.51-57
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• 1998

A study was carried out to understand some parameters affecting on RAPD analysis with Lactobacillus species. From the results, we found that appearance of specific DNA bands were very influenced by the concentration of $MgCl_2$ but it was overcome by applying enough amount of Taq DNA polymerase. Other parameters such as concentrations of template DNA, random primers and Taq DNA polymerase have enhanced the production of specific DNA bands by increasing their concentration applied. However, we noticed that G/C contents of random primers did not show any correlations with number of specific RAPD bands generated but the RAPD results were heavily influenced by the characteristics of the random primers, that is, the sequences of the oli.

• Archives of Plastic Surgery
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• v.43 no.6
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• pp.538-543
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• 2016

Background Cutaneous squamous cell carcinoma (SCC), which occurs in keratinocytes of the epidermis and is the second most common skin cancer, has a more invasive growth pattern and higher potential to metastasize than basal cell carcinoma. Total excision of the primary tumor is the treatment of choice. For clear excision of the tumor, invasion depth is one of the most important factors. This study was conducted to clarify the relationship between the size and the invasion depth of cutaneous SCC. Methods Twenty-six cases were collected for this prospective study. Frozen biopsies were examined after complete resection of the tumor, followed by histological confirmation by pathological examination. The major and minor axis lengths of the tumor, the invasion depth, and the level of invasion were measured. Recurrence or metastasis was recorded through regular follow-up. Results The Pearson correlation coefficient was used for statistical analysis. Significant results were observed for the relationship between the major and minor axis lengths and the invasion depth of the tumor (0.747, 0.773). No cases of recurrence or metastasis were observed. Conclusions In head and neck cutaneous SCC, the invasion depth of the tumor is closely related to the major and minor axis lengths of the tumor. Therefore, the invasion depth of the tumor can be estimated by measuring the size of the tumor, and a standard vertical safety margin for head and neck cutaneous SCC can be established, which could be helpful in the development of a preoperative reconstruction plan.