• Journal of Educational Research in Mathematics
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• v.22 no.4
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• pp.495-515
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• 2012

This study is to diversely analyze teachers' Pedagogical Content Knowledge (PCK) regarding to the area of plane figures and discuss the consideration for the materialization of the effective class in learning the area of plane figures by identifying the improvements based on problems indicated in PCK. The subjects of inquiry are what the problems with teachers' PCK regarding to the area of plane figures are and how they can be improved. In which is the first domain of PCK, teachers need to fully understand the concept of the area and the properties and classification of the area and length, recognized the sequence structure as a subject of guidance and improve the direction which naturally connects the flow of measurement by using random units in guidance of the area. In which is the second domain of PCK, teachers need to establish understanding of the concept for the area and understanding of a formula as a subject matter object and improve the activity, discovery and research oriented class for students as a guidance method by escaping from teacher oriented expository class and calculation oriented repetitive learning. They also need to avoid the biased evaluation of using a formula and evenly evaluate whether students understand the concept of the area as a performance evaluation method. In which is the third domain of PCK, teachers need to fully understand the concept of the area rather than explanation oriented correction and fundamentally teach students about errors by suggesting the activity to explore the properties of the area and length. They also need to plan a method to reflect student's affective aspects besides a compliment and encouragement and apply this method to the class. In which is the fourth domain of PCK, teachers need to increase the use of random units by having an independent consciousness about textbooks and supplementing the activity of textbooks and restructure textbooks by suggesting problematic situations in a real life and teaching the sequence structure. Also, class groups will need to be divided into an entire group, individual group, partner group and normal group.

• Journal of Korean Society of Transportation
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• v.33 no.5
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• pp.497-507
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• 2015

Nonrecurrent congestion of freeway was primarily caused by incident. The main cause of incident was known as a traffic accident. Therefore, accurate prediction of traffic incident clearance time is very important in accident management. Traffic accident data on freeway during year 2008 to year 2014 period were analyzed for this study. KNN(K-Nearest Neighbor) algorithm was hired for developing incident clearance time prediction model with the historical traffic accident data. Analysis result of accident data explains the level of accident significantly affect on the incident clearance time. For this reason, incident clearance time was categorized by accident level. Data were sorted by classification of traffic volume, number of lanes and time periods to consider traffic conditions and roadway geometry. Factors affecting incident clearance time were analyzed from the extracted data for identifying similar types of accident. Lastly, weight of detail factors was calculated in order to measure distance metric. Weight was calculated with applying standard method of normal distribution, then incident clearance time was predicted. Prediction result of model showed a lower prediction error(MAPE) than models of previous studies. The improve model developed in this study is expected to contribute to the efficient highway operation management when incident occurs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.761-770
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• 2017

The objective of this study is to propose a community facility design for the revitalization of the piloti spaces of deteriorated low-rise residential blocks. For this study, the precedent research and institutional limitations are examined. In addition, this study selected and analyzed a deteriorated low-rise residential block utilizing pilotis. Generally, in this type of residence, 8 to 10 generations live together in multi-family houses and row houses, so it is a type of housing that lacks both public space and parking places. Therefore, we attempted to improve the situation of the communities by making use of the space between the pillars and walls without infringing on the parking places. In addition, we took into consideration the design and arrangement of the piloti by evaluating the inconveniences and needs of the residents through interviews. Specifically, various modules were planned and used to transform the spaces between the pillars of the pillar type piloti structure. This study examined the possibilities offered by various materials and modules, and studied the diverse possibilities that can be offered by changing the modules.

• Journal of The Korean Association of Information Education
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• v.13 no.3
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• pp.383-391
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• 2009

The goal of cyber teaching is to reduce the cost of private lessons, dissipate the educational disparity amongst regions, make classes apt to the given level of every group of students, make up for systematic defects of the public education, and ultimately strengthen its role. This study intends to analyze the capabilities of cyber teachers and clarify their qualifications, as the whole new e-Learning system is about to take root. In this study, the activities of cyber teachers are analyzed and some standards of applicability of cyber teachers, or the so-called ISSCT, are presented. Firstly, the activities are divided into teaching, counselling, process management, development of professionality. Based upon these four activities, nine tasks have been formed and the structure of 22 sub-tasks has been completed. This is the way the standards of applicability of cyber teachers are established in consideration with their activities. Secondly, the standards of information capability of cyber teachers have 53 elements in total, and the aforementioned ISSCT are presented in relation to the ISST, based upon the standards of information capability of cyber teachers.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.193-198
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• 2008

ErmSF is one of the proteins which are produced by Streptomyces fradiae to avoid suicide by its autogenous macrolide antibiotic, tylosin and one of ERM proteins which are responsible for transferring the methyl group to $A_{2058}$ (Escherichia coli coordinate) in 23S rRNA, which reduces the affinity of MLS (macrolide-lincosamide-streptogramin B) antibiotics to 23S rRNA, thereby confers the antibiotic resistance on microorganisms ranging from antibiotic producers to pathogens. ErmSF contains an extra N-terminal end region (NTER), which is unique to ErmSF and 25% of amino acids of which is arginine known well to interact with RNA. Noticeably, arginine is concentrated in $^{58}RARR^{61}$ and functional role of each arginine in this motif was investigated through deletion and site-directed mutagenesis and the activity of mutant proteins in cell R60 and R61 was found to play an important role in enzyme activity through the study with deletion mutant up to R60 and R61. With the site-directed mutagenesis using deletion mutant of 1 to 59 (R60A, R61A, and RR60, 61AA), R60 was found more important than R61 but R61 was necessary for the proper activity of R60 and vice versa. And these amino acids were presumed to assume a secondary structure of $\alpha$-helix.

• Journal of Environmental Impact Assessment
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• v.26 no.3
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• pp.181-194
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• 2017

While over 90 percent of fishways are made up with concrete material, nature-like fishways are started to be established as a form of small stream using natural materials. Recently, the central government in collaboration with a university has proposed a 'Standard Model of Nature-like Fishway' with a purpose to provide as a national design standard of nature-like fishway. This study aims to criticize the proposed design model of nature-like fishway and to propose improvements by examining other international cases. As a result, we found problems and limitations of the proposed design model due to the lack of research and experience about making nature-like fishway in Korea. Especially, for designing bypass nature-like fishway we found the lack of studies about structure management strategies, establishment of rocks or pebbles inside the stream, and natural materials. In this sense, more studies about nature-like fishway design adaptable to our environment need to be conducted. In addition, since the proposed design standard for nature-like fishway has been created based on the limited examination of existing domestic cases, it is desirable to improve the design standard on the basis of hydrological and biological research so that they could be adapted effectively to regional and local contexts.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.181-192
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• 2013

Given both structural safety and economic benefits of aging facilities, remodelling of the existing facilities is preferable to reconstruction. This recognition provides an opportunity to reduce the commitment of resources and national budget. However, when a subordinate troop asks for remodeling or reconstruction of a deteriorated facility, it is difficult to ensure the consistency and objectivity in the process of decision making for the alternatives due to the absence of systematic and quantitative rating methodology. Their economic evaluation methodology only exists in a manual format. Thus, further research is required for converting the methodology into an automated system in view of practicality such as rapid and accurate data processing. The contributions of this study are as follows: 1) Literature review found out a representative economic evaluation model focused on military facilities, and comparative analysis with a similar study identified the strength and weakness. 2) this study presented how to convert the theoretical framework which enables to solve a specific subject matter into an automated system. 3) it developed a user friendly interfaces which consist of four functional modules by considering the usability and accessibility of the system user. 4) the developed system was verified by a case study in terms of four kinds of performance indicators.

• Fire Science and Engineering
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• v.29 no.2
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• pp.44-53
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• 2015

This study is a survey research to improve the fire-fighting ambulance interior design safer and more efficient to identify the type of structure and functional problems 119 ambulance. When the paramedics and four degrees to over 755 people modify the target report and related literature on the future development of an ambulance for patient safety at the 2007 British National Patients Safety Agency (NPSA) and was used as a complementary tool. General characteristics questionnaire was composed of items for your design improvements for ambulance promote safety and efficiency. The data were collected by distributing a questionnaire e-mail or in person. The collected data were processed using the SPSS 20.0 statistical program, the general characteristics as frequency analysis, percentage, ambulance interior design improvement-related items were analyzed using the chi-square verified. As a result, this research elicited that vans converted fire ambulance cars have a problem with the narrow interior space and truck converted fire ambulance cars should be comfortable to drive in ride quality. In addition, we also found that the improvement of paramedics treatment position and the paramedic's personnel safety belt are required. Based on these results, we propose that a number of improvements are needed in the fire-fighting ambulance car.

• Bulletin of the Society of Naval Architects of Korea
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• v.26 no.3
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• pp.51-61
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• 1989

Recently, the growth in the propulsion power and propeller size of typical energy saving ships has resulted in severe damages of the oil-lubricated stern tube bearing. Consequently, a more rational analytical method for the design of the shafting system is required. In this paper an analytical method applicable to the design of the oil-lubricated stern tube bearing and shafting system is presented. The method consists of the finite element analysis of the shafting system and the oil film hydrodynamics. The shafting system is modeled as a three-dimensional problem using beam elements taking account for the steady components of thrust, lateral forces and moments of the propeller as well as the elastic foundation effects. The oil film hydrodynamics is modeled as a two-dimensional problem. Equal and retangular elements employing hourglass control method are used for the construction of the oil film fluidity matrix. To search the quasi-static equilibrium position between the propeller shaft and the oil film, an optimization technique is employed. Some numerical results based on the proposed method are compared with some measured and numerical data available. They show acceptable agreements with the data.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.6
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• pp.1707-1721
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• 2014

Half-depth panels were developed with the merits of CIP (Cast In Place) decks and precast decks for constructability and fast construction. In this paper, details of half-depth panels with pre-tensioning were suggested. For evaluation of structural performance, five half-depth panel specimens were fabricated and static tests were conducted. The cross-sections of these specimens were composed of pre-tensioned half-depth panels and pre-tensioned two-span half-depth panels. Test parameters were the amount of the prestressing force and the longitudinal reinforcements. Static tests on simply-supported slabs showed that ultimate strength was 1.55 times greater than calculated nominal strength. The flexural strength was only 10 % increased and the influence on crack width control was negligible when the member of tendons was increased twice. For two-span continuous specimens, the ultimate strength increased 1.2 times and 1.38 times respectively as the reinforcement was additionally provided. The verified half-depth panels by this research can be effectively utilized for the fast replacement or construction of bridges.