• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.5-5
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• 2011

The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.

• Journal of Korean Home Economics Education Association
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• v.26 no.4
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• pp.85-114
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• 2014

The main purpose of this study was to develop teaching and learning plans and a smart textbook for food and nutrition education in Home Economics focusing on 'healthy diet and meal plans' unit in "Technology home Economics" textbooks for 7th graders to evaluate the effectiveness of the instruction conducted with the smart textbook. The content of the study to achieve the purpose is as follows: First, design a smart education-based teaching and learning curriculum for food and nutrition education in Home Economics, focusing on 'healthy diet and meal plans' unit. Second, develop a smart textbook for food and nutrition education based on the teaching and learning curriculum, using a smart content authoring tool. Third, evaluate the effectiveness of the instruction after applying the curriculum in real classroom situations. The results of this study were as follows: First, teaching and learning plans and materials were developed for two units, 'issues regarding teenagers' diet' and 'implementation of a healthy and balanced diet', under 'teenagers' life'. The first unit, 'issues regarding teenagers' diet', dealt with topics such as teenagers' dietary behaviors, nutrition, and health. Learning objectives for this unit were to help students identify and evaluate their own dietary behaviors. The second unit, 'implementation of a healthy and balanced diet', encouraged students to diagnose problems with their diet and plan nutrient rich meals. The objectives for this unit were to help students implement a healthy and balanced diet by providing them with nutrition and dietary guidelines for Koreans, sample meal plans, and guidelines for developing healthy eating habits for teenagers. In order to develop a teaching and learning plans to achieve these objectives, teaching and learning materials including inquiry tasks, materials for group activities, multimedia, applications and various pop-up learning materials were developed. Second, a smart textbook using DocZoom, which was a smart content authoring tool was developed. The textbook dealt with issues regarding teenagers' diet and implementation of a healthy and balanced diet. Multimedia material used in the textbook come from the Ministry of Food and Drug Safety's food and nutrition education web sites and other sources. To develop student-oriented material, relevant video clips were added to the smart textbook to motivate students and enhance their interest in the course. Third, the outcome of this study indicated that the instruction using teaching and learning plans and learning materials with the smart textbook was effective for enhancing students' interest in Home Economics classes (t-value=-3.99, p<.001), creating enthusiasm for learning(t-value = -2.61, p<.05), encouraging self-directed and independent learning(t-value = -4.77, p<.001), and improving students' interest in food and nutrition courses(t-value = -3.83, p<.001). The students' evaluation of the instruction were as follows: the instruction using teaching and learning plans and learning materials with smart textbooks, instead of paper textbooks, helped them save time looking for learning materials; students evaluated that it was easier for them to see and understand video clips and charts. In addition, most students answered that instruction with smart textbooks were more fun and convenient, and they agreed that the courses enhanced their learning experience.

• Journal of the Korean Society of Radiology
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• v.5 no.5
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• pp.231-235
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• 2011

Radium is rock or soil of crust or uranium of building materials and thorium after radioactivity collapse process are created colorless and odorless inert gas that accrue well in sealed space like mine or basement. It inflow to lung circulate respiratory organ and caused lung cancer because of deposition of lung or bronchial tubes. Radium sheath of medical institution treat person's life is possible big danger to professional regarding radioactivity who has much amount exposed radioactivity and weaker immune patient. so we do this test. Using measuring instrument at test is real time radium measuring instrument, Professional Continuous Radon monitor, and measuring places are basement first floor and second floor of two hospitals and measure from 10 a.m to 3 p.m. Measurement result of Professional Continuous Radon monitor is minimum 14.8 Bq/$m^3$ to maximum 70.3 Bq/$m^3$ and show domestic baseline below 148 Bq/$m^3$, effective dose-rate is minimum 0.296 mSv to maximum 1.406 mSv that show 2.4 mSv, 10~58.3% level, exposed radiation amount from nature radiation one year.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.793-801
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• 2013

Our society is moving from a monocultural society of a homogeneous nation to a multi-cultural society as a lot of foreigners are flowing into the country with the advent of globalization and with an effort to secure labor force for economic growth. So, multi-cultural families composed of members using different languages spring up everywhere, but the children in these multi-cultural families have difficulties in acquiring Korean language and are socially maladjusted because of the bilingual environment. The goal of this study is to help enhance the language capabilities and socialities of the children in the multi-cultural families through fine arts using artistic methods. The study method was to analyze the high-quality effects of the fine arts with the theoretical research materials and theses showing the real conditions of the multi-cultural families. And I proposed some ways to improve the linguistic abilities and socialities of the children in the multi-cultural families with the utilization of fine arts. As a result, Firstly, An active use of the bilingual instructors and artistic multimedia is educationally necessary to overcome language restrictions. Secondly, Various ways to utilize fine arts are necessary to improve learning abilities of other subjects. Thirdly, Artistic plays and experiential activities need to be largely applied to education to enhance the abilities of emotional control and socialities. Finally, Integrated culture and art education is essential not only for creativities and socialities but also for personalities for community life.

• Journal of the Korean School Mathematics Society
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• v.20 no.3
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• pp.277-302
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• 2017

Educational objectives for mathematics in the curriculum revised in 2009 and the curriculum revised in 2015 put great emphasis on practical use of math, but perception of that lacks at schools. Accordingly, this research is recognizing the need for paying attention to curriculum focusing on mathematical connectivity and is inspecting CMP curriculum which has been developed over the years to reinforce problem solving competence and improve communication skills. This study analyzes CMP textbooks published as third edition in 2014 after several revisions, focusing on equations, inequalities and functions. First, this thesis analyzes mathematical connectivity using a new analysis framework which applied the modes of representation(situations, verbal description/ tables/ graphs/ formulae) made by Janvier(1987). Second, this research analyzes connectivities between different units, various sections, other subjects and practical contents related to the real life. The results: CMP textbooks use various practical materials for specific situations. They represent twelve processes of connectivity according to the modes of representation of Janvier. The books also show relationship between equations and functions, between inequalities and functions. And CMP textbooks include other subjects and practical contents.

• Journal of Educational Research in Mathematics
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• v.23 no.2
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• pp.213-235
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• 2013

The purpose of this study is to analyze how the teaching activities which used EXCEL influence the specialized high school underachieved students. They have difficulties in making use of various representations for better understanding of function. EXCEL is helpful for learning function because it enables the students to use real life materials in math learning as well as formulates Tabular, Algebraic and Graphical which represent function. Furthermore, the students in specialized high school also have the experience of using EXCEL while studying other subjects. For that reason they have no burdens and fears on using EXCEL in learning activities. Utilizing EXCEL in the classroom gives an expectation that it helps to have interests on studying function and prepare for the next learning in the end. Research classes were conducted in a group of five students who have different hopes of career and a variety of mathematical interests. Though the students couldn't transfer Algebraic to Graphical in the diagnostic evaluation, they could resolve the problem of connections between Graphical, Tabular and Algebraic in the process perspectives, and could also express graphical representation by linking object perspectives with process perspectives. Therefore, they solved the connection problem of Tabular, Algebraic and Graphical in the object perspectives. As a result, the students could make transitions between Algebraic and Graphical in object perspectives through the classes applying EXCEL. Consequently, teaching the students with underachievement utilizing EXCEL enables them to recover their interests on math and it helps them to complete their following curriculum.

• School Mathematics
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• v.4 no.3
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• pp.375-399
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• 2002

When a curriculum change is being an issue, the editorships and the promotive directions reflect to supplement the social requests. However it is often criticized that such changes in the textbook itself are not satisfactory enough as to coherent to the editoships. And we set the following research questions; (1) One of the most important changes in the new 7th curriculum is to encourage the students' activities. We checked if it is well suited in the new textbooks. (2) Often textbook itself is not important In class, while instructor or students want something else other than the one suggested in the textbook. We asked 187 teachers how they use the textbooks in class. To answer (1), we checked up the introductory - activity - contents with 7 categories, which are ${\circled1}$ of real life sources ${\circled2}$ in use of concrete manipulative ${\circled3}$ in use of computers or calculators ${\circled4}$ in use of historical resources ${\circled5}$ stimulating to recall a relevant previous knowledges ${\circled6}$ of coherence between the activity and the exploratory contexts. ${\circled2}$ were increased, rewarding to the decrease of ${\circled5}$, in the new textbooks, while changes in ${\circled3}$ and ${\circled4}$ were not enough to talk about increments. Especially slight decrease in ${\circled6}$ were detected and it seemed to attribute to the unmatchable use of ${\circled1}$ and ${\circled2}$ with the explanation of mathematical subjects, which also implies how difficult to match ${\circled1}$ and ${\circled2}$ with ${\circled6}$. Analyzing the reponses of (2), about 70% of the teachers used the introductory activities in the textbook, which led better attention of sudents, while 30% of teachers do not use it because they felt that its inroductory activities had not been adequate for their purposes. Teachers counted inadequacy reasons for not being helpful in class, lack of time or lack of support of students, etc. Those teachers use introductory activities invented of their own for classes. As some results of the study, we suggest firstly that authors of textbooks have to get more informations to provide ways to entcourage students' interest in mathematics classes. The ways must be practical and brain storming as well as More use of computers and calculators and mathematical history are expected. Secondly, we are emphasizing the feedbacks between the textbook authors and the users(teachers and students) through internet. Which, we anticipate, will get better communications between them and be a good foundations of continuous modifications of textbooks.

• Journal of The Korean Association For Science Education
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• v.30 no.4
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• pp.452-471
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• 2010

As the Korean College scholastic Ability Test (CSAT) has been implemented for 17 years since 1994, it is becoming more and more difficult to make new items that haven't been previously used to measure students' thinking ability. Therefore, it is necessary to keep conducting research on making new test items that can measure students' scholastic ability reliably. For this reason, multiple choice items on the Japanese university entrance exam, which is a Japanese National Center Test for University Admissions (NCTUA) equivalent of CSAT, were analyzed in order to draw implications for CSAT item development. In this study, we analyzed the Japanese NCTUA administered in January 2009 to investigate the structure of its science test. We also analyzed the NCTUA items by the domains of contents and behaviors, and tried to predict item difficulty from the perspective of Korean applicants. Major findings are as follows: Most NCTUA items measure understanding knowledge or low level thinking ability. Also the alloted time for each item is longer than CSAT. The number of test items, and the number of choice and alloted points for each item are diverse, unlike CSAT. The number of items using real-life materials are much more, but the items are not rigorous in sentence expression compared to CSAT. And the difference of difficulty level among science tests were larger with reference to CSAT. Also science score is required for most applicants regardless whether they are taking liberal arts or going onto the science track.

• The Journal of the Korea Contents Association
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• v.14 no.1
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• pp.337-345
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• 2014

The visually impaired who have many restrictions on their sight due to impairment of a sense of sight among special senses have substantial difficulties in the areas ranging from very minor behavior in their house to the external activities for social life. Visual impairment may cause many problems in various behaviors for protecting health which have recently drawn a lot of interests. As a method of analysis of collected data, this study conducted the frequency analysis of general characteristics and oral health behavior of the subjects, compared the average of oral public health behavior and oral health condition through t-test and F-test, and conducted the post verification of significant difference among groups with Duncan. For identifying the relevancy between the general characteristics and the oral health behavior, this study conducted Spearman's correlation analysis, and for identifying the impact on subjective, oral health condition, this study conducted multiple regression analysis. SPSS (SPSS20.0 for Windows, SPSS Inc, USA) was used as a statistical program, and the level of significance for determining statistical significance was considered at the level of 0.05. Because the visually impaired are the group whose behaviors for protecting health should be accurately recognized, this study intends to utilize the findings as basic materials for making information communication media suitable for the visually impaired by identifying the real conditions and behaviors of their oral health and analyzing their oral condition caused by such behaviors. With the help of information technology.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.689-692
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• 2015

Background: Incorporation of molecular analysis of the epidermal growth factor receptor (EGFR) gene into routine clinical practice has shown great promise to provide personalized therapy of the non-small cell lung cancer (NSCLC) in the developed world. However, the genetic testing of EGFR mutations has not yet become routine clinical practice in territories remote from the central regions of Russia. Therefore, we aimed to study the frequency of major types of activating mutations of the EGFR gene in NSCLC patients residing in West Siberia. Materials and Methods: We examined EGFR mutations in exons 19 and 21 in 147 NSCLC patients (excluding squamous cell lung carcinomas) by real time polymerase chain reaction. Results: EGFR mutations were detected in 28 of the 147 (19%) patients. There were 19 (13%) cases with mutations in exon 19 and 9 cases (6%) in exon 21. Mutations were more frequently observed in women (42%, p=0.000) than in men (1%). A significantly higher incidence of EGFR mutations was observed in bronchioloalveolar carcinomas (28%, p=0.019) and in adenocarcinomas (21%, p=0.024) than in large cell carcinomas, mixed adenocarcinomas, and NOS (4%). The EGFR mutation rate was much higher in never-smokers than in smokers: 38% vs. 3% (p=0.000). The frequency of EGFR mutations in the Kemerovo and Tomsk regions was 19%. Conclusions: The incorporation of molecular analysis of the EGFR gene into routine clinical practice will allow clinicians to provide personalised therapy, resulting in a significant increase in survival rates and improvement in life quality of advanced NSCLC patients.