• Molecules and Cells
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• v.25 no.2
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• pp.294-300
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• 2008

Cytokinins are essential hormones in plant development. $\underline{A}$rabidopsis $\underline{h}$istidine-containing $\underline{p}$hosphotransfer proteins (AHPs) are mediators in a multistep phosphorelay pathway for cytokinin signaling. The exact role of AHP4 has not been elucidated. In this study, we demonstrated young flower-specific expression of AHP4, and compared AHP4-overexpressing (Ox) trangenic Arabidopsis lines and an ahp4 knock-out line. AHP4-Ox plants had reduced fertility due to a lack of secondary cell wall thickening in the anther endothecium and inhibition of IRREGURAR XYLEMs (IRXs) expression in young flowers. Conversely, ahp4 anthers had more lignified anther walls than the wild type, and increased IRXs expression. Our study indicates that AHP4 negatively regulates thickening of the secondary cell wall of the anther endothecium, and provides new insight into the role of cytokinins in formation of secondary cell walls via the action of AHP4.

• Hwankyungkyoyuk
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• v.17 no.2
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• pp.10-25
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• 2004

This study aims to standardize and analyze the environmental teacher recruitment examination for secondary school. To achieve the purpose, the environmental teacher recruitment examinations, which were carried out for five times through the school year 2000 to 2004, were compared and analyzed. And then, based on the above analyses, we presented ‘the plan of standardization for the environmental teacher recruitment examination in secondary school.’ In addition, the propriety, reliance, and realistic suitability of the plan were confirmed by professors of environmental education department in universities, environmental education professionals, and environmental teachers in secondary school. By presenting ‘the plan of standardization for the environmental teacher recruitment examination in secondary school’ in this study, we expect that the curriculum design and management of environmental education teacher training universities can be standardized and improved, and that the teacher who have expert qualities in environment education is reasonably selected by the environmental teacher recruitment examination.

• Research in Mathematical Education
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• v.17 no.2
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• pp.79-97
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• 2013

This paper reports findings from a survey of senior secondary school students' epistemological conceptions of mathematics with the adaption of the instrument of the "Conceptions of Mathematics" - Inventory in China. The survey included a sample of 414 Grade 10 students, 441 Grade 11 students, and 400 Grade 12 students from three provinces. Descriptive statistics, one-way ANOVA, and T-test were employed to analyze data in this study. It was found that senior secondary school students mainly focused on objectivity and reality of mathematics, without highlighting the characteristics of sociality, subjectivity, and creativity of mathematics. In addition, besides gender differences, differences were identified among students from different grades, different areas, taught by teachers with different teaching experience and experience in using reformed curriculum.

• Journal of The Korean Association For Science Education
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• v.21 no.5
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• pp.944-967
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• 2001

The purpose of this study is to compare and analyze secondary school chemistry education in Korea and China in order to identify implications for the improvement of Korean chemistry education. The school systems, curricula, and teacher education related to secondary chemistry education of both countries were compared and analyzed. The 6-3-3-4 school system is used in both countries, and national school curricula are formulated by the Ministries of Education in both countries. The 1996 chemistry curricular standard for advanced middle schools in China, and 1997 chemistry curriculum for Korean high schools were compared in several aspects, followed by comparisons of chemistry teacher education in both countries. Based on the comparative analysis of chemistry education, some ideas and issues which provide implications for improving Korean high school chemistry education were identified. Chemistry teaching in the junior secondary schools, tentative implementation of curricula, required course work in chemistry, structure of curricula, oral assessments, probation of teachers and other issues are identified and discussed in this study.

• Research in Mathematical Education
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• v.15 no.2
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• pp.105-114
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• 2011

During the 20th century, the secondary school mathematics teaching in China had been developing from the an old-style private school form with individual instruction to classroom teaching with Chinese characteristics, which experienced three stages of development; the stage for the formation of modern teaching system (1902-1949), the stage for development (1950-1976), and the stage for innovation (1977-2000). The characteristics and journey for the transformation will exert great for reference and effects for the reform of secondary school mathematics teaching nowadays.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4446-4462
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• 2019

In this paper, we focus on interference cancellation for three-hop cognitive radio networks (CRNs) over Rayleigh fading channels. In CRNs, secondary users (SUs) are allowed to opportunistically utilize the licensed spectrum during the idle time of primary users (PUs) to achieve spectrum sharing. However, the SUs maybe power constrained to avoid interference and cover a very short transmission range. We here propose an interference cancellation scheme (ICS) for three-hop CRNs to prolong the transmission range of SUs and improve their transmission efficiency. In the proposed scheme, a flexible transmission protocol is adopted to cancel the interference at both secondary relays and destinations at the same time. And a closed-form expression for the secondary outage probability over Rayleigh fading channels is derived to measure the system performance. Simulation results show that the proposed scheme can significantly reduce the secondary outage probability and increase the secondary diversity in comparison with the traditional cases.

• Journal of the Korean Society of School Health
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• v.7 no.1
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• pp.9-28
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• 1994

This study is to investigate the status and problems in the anual physical examination in elementary & secondary schools. The study helps the introduction of health assessment. Two hundreds and forty nurse teachers of elementary & seconcary school in Seoul received in-service traomong fpr 20 daus frp, September 7 to September 27, 1992. Questionnaires were given to the 240 teachers and the number of collected questionnaire is 112. The result of the questionnaire analysis is like the following. First, the answered teachers aged 35~39, 36.6%; experience 6~10 years 37.5%; the number of class 31~40, 28.6%. Among the answered of the school doctors is practicioners. The doctors major subjects are 26.8% of internal medicine and 35.7% of surgery. Second, in elementary & secondary school nurse teachers received in-service training for the primary health assessment. And then 37.5% of schools practiced the health assessment. The term of the health assessment is largely a-year-length, occurately its rate of schools have practiced the assessment reaches 81.0%. The number of health assessment are consist of eyes, nose, ear, throat, skin, spine, heart and other abnormal regions and diseases all over the body. And 83.3% of the rate of the health assessment includes all these contents. The period of the health assessment is 7 to 28 days. Third, the physical examination conducted by school doctors is 91.0%. The method is various; one is 56.6% of the students who checked first by he nurse teacher. The number of 15.1% of the schools is directly checked by the school doctor. The invited medical doctors are divided into two categories. The number of general physician is 61.9%. Contrary to that school doctors are 38.1%. The contents of the medical examination is all the items printed on the medical examination sheet. To follow the medical examination sheet the number of school is 59.6%. Eyes, throat, skin and heart etc. partly medical examination is 40.4%. The rate of schools that used only stethoscope, tongue pressor as the medical instruments reaches 53.4% and 87.1% of elementary & secondary school give the invited doctors the allowance a nurse teachers conference decided. The number of 8.9% schools pay the doctors independent allowance. The medical examomatopm allowance is 200 to 250 won per capita. The rate is 56.1%. Forth, after the medical examination 72.1% of school sends letter to the parents to notice the result of the examination. The number of response from parent is 12.5%. The observation record in secondary school is 70.6% for junior, and 80.0% for senior respectively, and 65.5% is for the elementary school children. To conclude the regular physical examination in elementary & secondary school is very important. Because the students are in the stage of rapid growth and development. Early finding of the students diseases can help to cure with ease. In the light of public health the management of health program in the elementary & secondary school is of consequence.

• Journal of Korean Society of Forest Science
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• v.97 no.5
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• pp.501-507
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• 2008

The data of crown width with 4 directions, DBH, tree height, and coordinate for sample trees were collected from 30 permanent sample plots in secondary fore st of the Maoershan Experimental Forestry Farm, Northeast China. In this paper, the competition of individual trees in stand were discussed for secondary forest by using iterative Hegyi competition index and crown overlap index that represented the competitive and cooperative interactions among neighboring trees. Active competitors of subject tree in the competition zone were selected to calculate the iterative competition index. Using the results of crown classification based on the equal crown projection area, a new distance dependent competition index called crown overlap index (COI) was developed for secondary forest. The COI performed well in describing the crown competition rather than crown competition factor (CCF). The individual-based competition index discussed in this paper will provide more precise for developing individual tree growth models for secondary forest and it can also use to adjust the stand structure for spatial optimal management.

• BMB Reports
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• v.44 no.2
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• pp.118-122
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• 2011

Most widely used secondary structure assignment methods such as DSSP identify structural elements based on N-H and C=O hydrogen bonding patterns from X-ray or NMR-determined coordinates. Secondary structure assignment algorithms using limited $C{\alpha}$ information have been under development as well, but their accuracy is only ~80% compared to DSSP. We have hereby developed SABA (Secondary Structure Assignment Program Based on only Alpha Carbons) with ~90% accuracy. SABA defines a novel geometrical parameter, termed a pseudo center, which is the midpoint of two continuous $C{\alpha}s$. SABA is capable of identifying $\alpha$-helices, $3_{10}$-helices, and $\beta$-strands with high accuracy by using cut-off criteria on distances and dihedral angles between two or more pseudo centers. In addition to assigning secondary structures to $C{\alpha}$-only structures, algorithms using limited $C{\alpha}$ information with high accuracy have the potential to enhance the speed of calculations for high capacity structure comparison.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.1
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• pp.43-48
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• 2019

This study investigates the electrochemical characteristics of the hybrid cell that combined the advantageous characteristics of Li secondary battery and supercapacitor, high energy density and high power density, respectively. Electrochemical behaviors of the hybrid cell was characterized by charge/discharge, cycle and impedance tests. The hybrid cell using Li secondary battery and supercapacitor had better discharge capacity and cycle performance than that of using Li secondary battery only. Proper design of such a hybrid cell system is expected to result in substantial benefits to the well being of the Li secondary battery. The hybrid cell involving Li secondary battery for high energy density and supercapacitor for high power density may be the possible solution for future energy storage system.