• 제목/요약/키워드: magic number

검색결과 44건 처리시간 0.025초

Electron-Impact Ionization Mass Spectroscopic Studies of Acetylene and Mixed Acetylene-Ammonia Clusters as a Structure Probe

  • Sung Seen Choi;Kwang Woo Jung;Kyung Hoon Jung
    • Bulletin of the Korean Chemical Society
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    • 제13권5호
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    • pp.482-486
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    • 1992
  • Ion-molecule reactions of acetylene and mixed acetylene-ammonia cluster ions are studied using an electron impact time-of-flight mass spectrometer. The present results clearly demonstrate that $(C_2H_2)_n^+$ cluster ion distribution represents a distinct magic number of n=3. The mass spectroscopic evidence for the enhanced structural stabilities of $[C_6H_4{\cdot}(NH_3)_m]^+$ (m=0-8) ions is also found along with the detection of mixed cluster $[(C_2H_2)_n{\cdot}(NH_3)_m]^+$ ions, which gives insight into the feasible structure of solvated ions. This is rationalized on the basis of the structural stability for acetylene clusters and the dissociation dynamics of the complex ion under the presence of solvent molecules.

A Study on Motives of Chinese Female Audiences for Watching Korean Fantasy TV Dramas

  • Wu, Yue;Shen, Xuezheng;Lee, Jong Yoon
    • International Journal of Contents
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    • 제17권2호
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    • pp.32-40
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    • 2021
  • With love as the theme and mythology, ghosts and magic as elements, Korean fantasy TV dramas have set romantic and beautiful plots and attracted a large number of Chinese female audiences. Based on Melodramatic Imagination and Stuart Hall's theory of "encoding/decoding", this paper investigated Chinese female audiences' motives of watching Korean fantasy TV dramas Hotel Druena through the form of focus group interviews to interpret reasons for the popularity of Korean fantasy TV dramas and Chinese women's overall cognition of Korean TV dramas from the perspective of female audiences. Thinking that South Korea's fantasy dramas are good at women's pursuit and desire for emotional elements, women who watch this type of south Korean TV dramas are temporarily relieving pressure of real life, thus satisfying the needs of female gaze and consumption.

GA3 처리가 유색칼라 괴경의 개화에 미치는 영향 (Effect of GA3 Treatment on the Flowering in Tuber of Zantedeschia 'Black Magic')

  • 박노복;임회춘
    • 현장농수산연구지
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    • 제7권1호
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    • pp.90-96
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    • 2005
  • GA3 침지시간과 농도에 따른 출현소요일수는 GA3 처리가 무처리에 비하여 1.1~4.0일 단축되었으며 생육특성도 GA3 처리가 양호한 경향이었으나 GA3 침지 시간과 농도에 따른 차이는 적었다. 개화소요일수는 GA3 처리가 무처리보다, 30분 침지가 10초 침지보다, 그리고 농도가 높을수록 단축되었으나 화경장, 화경폭, 화고 및 화폭 등은 처리간 차이가 없었다. 또한 개화수는 GA3 농도에 따른 효과가 커서 250~500 mg·L-1 처리가 4.0~4.3개로 최고 2배 많았으나 GA3 침지 시간에 따른 개화수 차이는 크지 않았다. 정상화율과 구근비대상황은 침지시간 및 농도에 관계없이 비슷하였다. 이로써 GA3 처리는 개화수 증가를 위해 반드시 필요하며 침지시간에 상관없이 처리농도는 250~500mg·L-1가 적당할 것으로 판단된다.

숫자퍼즐 활동이 초등학교 6학년 학생들의 수학적 창의성과 수학에서의 창의적 태도에 미치는 영향 (A Study on the Effect of playing Number Puzzle to Develop Mathematical Creativity and Creative Attitude in Mathematics for 6th Grader)

  • 백태진;이광호
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제21권2호
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    • pp.93-109
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    • 2018
  • 본 연구의 목적은 숫자퍼즐 프로그램과 수학적 창의성 검사지의 개발 및 적용으로 학생들의 수학적 창의성과 수학에서의 창의적 태도의 변화를 살펴보는 것이다. 이러한 목적을 달성하기 위해서 초등학교 6학년 36명을 대상으로 아침 활동시간 30분을 활용하여 마방진, 수도쿠(Sudoku), 켄켄퍼즐(kenken puzzle)로 연구를 수행하였고 활동 전 사전 검사와 활동 후 사후 검사를 통해 자료를 수집하였다. 숫자퍼즐 활동은 학생들의 수학적 창의성 및 수학에서의 창의적 태도의 향상에 긍정적이었으며, 남학생 보다 여학생의 수학적 창의성을 기르는데 도움이 된다는 것을 알 수 있었다.

한국과 뉴질랜드 초등학교 저학년의 덧셈과 뺄셈 지도방법에 관한 고찰 (A Note on Teaching Method of Addition and Subtraction between Korea and New Zealand Primary School)

  • 최창우
    • East Asian mathematical journal
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    • 제31권4호
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    • pp.505-525
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    • 2015
  • The purpose of this study is to analyze teaching method of addition and subtraction of whole number in Korea and New Zealand lower grade textbook and to get some suggestive points to develop mathematics curriculum and for a qualitative improvement of textbook. To do this, we will analyze focusing on teaching material, type and method of teaching, cases of real teaching and in the case of New Zealand, we will analyze portfolios together to see what kind of things do they deal with related to addition and subtraction. From these analyzing, the results are as follows: First, the guideline of accomplishment of group of year are stated in 2009 revised curriculum in Korea but it is rough. On the other hand, the level of accomplishment from kindergarten to high school are stated divided by eight kinds of thing in New Zealand curriculum. Second, there were common and different points in the aspect of teaching material. The common points are that both of our Korea and New Zealand are using materials related to real life intimately and the diifferent points are to use technology such as calculator and computer. They are more widely used in New Zealand than our Korea. Third, Korea had used routine method mainly but New Zealand had used method to develop creativity of learner such as to write problem corresponding to expression, posing problem corresponding to information, to complete table and find pattern and to write word problem to explain pattern and so on. Fourth, we could see special calculation strategies in the case of teaching addition and subtraction such as concept of double, compensation, various strategy based on counting of number, addition of the same number, magic square, near-double which are not finding in our mathematics textbook. Fifth, in the New Zealand textbook they had used teaching methods inducing curiosity of learner such as finding message and puzzle problem than solving given problem simply.

$^{31}$P NMR을 이용한 카올리나이트에 흡착된 인산염의 연구 (A Study of Phosphate Adsorption on Kaolinite by $^{31}$P NMP Spectroscopy)

  • 김영규
    • 한국광물학회지
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    • 제13권4호
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    • pp.186-195
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    • 2000
  • To study phosphate adsorption on kaolinite, $^{31}$ P MAS NMR(magic angle spinning nuclear magnetic resonance spectroscopy)has been used for kaolinite reacted in 0.1 M phosphate solutions at pH’s from 3 to 11. There are at least 3 different forms of phosphate on kaolinite. One is the phosphate physically adsorbed on kaolinite surface (outer-sphere complexes) or species left after vacuum-filtering. The second is the phosphate adsorbed by ligand exchange (inner-sphere complexes), and the third is Al-phosphate precipitates which are pH dependent. Most of the inner-spherer complexes and surface precipitates are mainly on hydroxided Al(aluminol) rather than hydroxided Si(silanol). These are pertinent with the results obtained from the phosphate adsorption experiments on silica gel and ${\gamma}$-Al$_2$O$_3$ as model compounds, respectively. The two peaks with more negative chemical shifts(more shielded) than the ortho-phosphate peak (positive chemical shift) are assigned to be the inner-sphere complexes and surface precipitates. The $^{31}$ P chemical shifts of the Al-phosphate precipitates are more negative than those of inner-sphere complexes at a given pH due to the larger number of P-O-Al linkages per tetrahedron. The chemical shifts of both the inner-sphere complexes and surface precipitates are more negative than those of inner-sphere complexes at a given pH due to the larger number of P-O-Al linkages per tetrahedron. The chemical shifts of both the inner-sphere complexes and surface precipitates become progressively less shielded with increasing pH. For the inner-sphere complexes, decreasing phosphate protonation combined with peak averaging by rapid proton exchange among phosphate tetrahedra with different numbers of protons is though to be the reason for the peak change. The decreasing shielding with increasing pH for surface precipitates is probably due to the decreasing average number of P-O-Al linkages per tetrahedron combined with decreasing protonation like inner-sphere complexes.

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SysML모델과 플랜트정보 간 상호연동을 위한 플러그인 개발 (A Plug-in Development for Interworking between SysML Model and Plant Information)

  • 김준영;이태경;차재민
    • 시스템엔지니어링학술지
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    • 제15권2호
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    • pp.17-30
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    • 2019
  • Due to difficulties in tracking design information of existing document-based configuration management, the research on the development of plant SysML model was started to apply the model-based system engineering methodology to comprehensively manage various design information. However, until now, in order to create the SysML model, the engineers are checking the design information and inputting it to the SysML model. This process requires a lot of time and manpower, it is required to minimize it. Therefore, this study has recognized the problem, a plug-in that extracts the plant design information in the design document and automatically converts the SysML plant model from it. Specifically, the development was performed in the following order. First, the extraction file was selected as the most commonly used Excel file as the plant design document. Next, the design information in the document was analyzed, and extracted information including tag number, name, and the capacity were selected. Finally, the plant SysML model conversion module was implemented. The developed plug-in is confirmed that the task load of the engineers by the SysML model conversion can be minimized and the model can be generated more quickly and accurately.

Korea-Japan English Camp: A Case Study of English Immersion Program in Korea

  • Park, Joo-Kyung
    • 영어어문교육
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    • 제12권4호
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    • pp.91-115
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    • 2006
  • English immersion has emerged in Korea only recently as an innovative approach to learning and teaching English. Lack of real life experience of using English has been one of the biggest obstacles for Korean learners of English and has resulted in an increasing number of children being sent to English-speaking countries and a huge amount of dollar outflow. This recent innovation is expected to be the magic wand to resolve all these problems. However, setting up an immersion program in a typical EFL context like Korea has brought in another set of issues and challenges. The purpose of this paper is to examine the effects of a short-term immersion English program in Korea and provide some empirical data to develop programs that can better cater to the needs of EFL learners. A two-week English immersion program was developed and implemented with 57 Korean and Japanese students whose grade level ranged from 4 to 12. The study results show that the program was successful in terms of changing the participants' attitude toward learning English, improving their English skills, enhancing intercultural understanding and competence, and motivating them for further studies of English and other foreign languages and cultures.

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Genomic Tools and Their Implications for Vegetable Breeding

  • Phan, Ngan Thi;Sim, Sung-Chur
    • 원예과학기술지
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    • 제35권2호
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    • pp.149-164
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    • 2017
  • Next generation sequencing (NGS) technologies have led to the rapid accumulation of genome sequences through whole-genome sequencing and re-sequencing of crop species. Genomic resources provide the opportunity for a new revolution in plant breeding by facilitating the dissection of complex traits. Among vegetable crops, reference genomes have been sequenced and assembled for several species in the Solanaceae and Cucurbitaceae families, including tomato, pepper, cucumber, watermelon, and melon. These reference genomes have been leveraged for re-sequencing of diverse germplasm collections to explore genome-wide sequence variations, especially single nucleotide polymorphisms (SNPs). The use of genome-wide SNPs and high-throughput genotyping methods has led to the development of new strategies for dissecting complex quantitative traits, such as genome-wide association study (GWAS). In addition, the use of multi-parent populations, including nested association mapping (NAM) and multiparent advanced generation intercross (MAGIC) populations, has helped increase the accuracy of quantitative trait loci (QTL) detection. Consequently, a number of QTL have been discovered for agronomically important traits, such as disease resistance and fruit traits, with high mapping resolution. The molecular markers for these QTL represent a useful resource for enhancing selection efficiency via marker-assisted selection (MAS) in vegetable breeding programs. In this review, we discuss current genomic resources and marker-trait association analysis to facilitate genome-assisted breeding in vegetable species in the Solanaceae and Cucurbitaceae families.

Ab initio DFT studies on dimerization and one-dimensional (1-D) polymerization of M@$Au_{12}$ (M = W, Mo) clusters

  • Park, So-Ra;Kim, Gunn;Kwon, Young-Kyun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.271-271
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    • 2010
  • Using ab initio density functional theory, we investigate the dimerization and one-dimensional (1-D) polymerization of metal-encapsulated gold nanoclusters, M@$Au_{12}$ (M=W, Mo) and their structural and electronic properties. M@$Au_{12}$ clusters with a magic number 13 can form icosahedral and cuboctahedral structures. We consider various dimer configurations with different compounds and symmetries to find the most stable dimer structure in each case. Au atoms in the one cluster, which participate directly in dimerization, tend to form triangular bonds together with counterpart Au atoms in the other. It is found that both M@$Au_{12}$ and M@$Au_{12}$ clusters are stabilized by about 3 eV due to dimerization. We also calculate and compare the electronic and magnetic properties of different dimerized clusters. Based on our investigation on dimerization, we further study on 1-D polymerization of M@$Au_{12}$ with different compounds and symmetries. We will also discuss their formation energies as well as their electronic and magnetic properties.

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