• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.12
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• pp.788-793
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• 2017

Electrical behaviors of plasma-sprayed $Al_2O_3-TiO_2$ coatings have been investigated in terms of their $TiO_2$ content. On increasing the $TiO_2$ content from 6 to 30 wt%, the DC electrical conductivity increased by several orders of magnitude. From impedance spectroscopy analysis, the total conductivity of the grains and grain boundaries and their respective activation energies were determined without the electrode effects that could impede ionic transfer. An electron transference number was also estimated, ranging between 6.5% and 7.3% for 13 wt% $TiO_2$ and between 0.4% and 0.7% for 30 wt% $TiO_2$ in the coating. Because of the high electronic contribution to the total conductivity, the $Al_2O_3-TiO_2$ coating could be a new candidate material to obtain superior electrical conductivity as well as corrosion and wear resistances.

• Journal of Agricultural Extension & Community Development
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• v.13 no.2
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• pp.277-286
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• 2006

The study aims at analysing the practical effects of "blended learning system" and participatory research methodology. The business programs are running by RDA. Even though many leading farms have been tried on binding technology and agribusiness, however business of farms in Korea are still in the beginning stage. The business program for leading farms of RDA is not only education program but also participatory research program. This program consist of on-line and off line, seminar and business homework etc. The main results of this paper are as follows: 1) to make organization of farms to accomplish business goals 2) to find out solution for urgent problems and subjects of farm management 3) to construct system for leading farms and on-line communities 4) to practice profitable business model for leading farms. Farms needs are not only technology transference, but business model for success of farm management.

• The Journal of Korean Association of Computer Education
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• v.19 no.6
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• pp.55-68
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• 2016

Informatics curriculum revised 2015 proposed the use of block type and text type of programming language by organizing problem solving and the programming unit in a spiral. The purpose of this study is to find out whether the algorithms helps programming learning and whether there is a positive transition effect in block type programming learning to text type programming trailing learning. For 15 elementary school students was conducted block type and text type programming learning. As a result of the research, it is confirmed that writing the algorithm in a limited way can interfere with the learner's expression of thinking, but the block type programming learning has a positive transition to the text type programming learning. This study is meaningful that it suggested a plan for the programming education which is sequential from elementary school.

• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.87-93
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• 1986

Yttria-bismuth-stabilized zirconia was investigated with respect to the amount of $Bi_2O_3$ addition in the ran-ge of 0.5~5mol% to the base composition of $(ZrO_2)_{0.92}(Y_2O_3)_{0.08}.Bismuth was introduced into the ma-terial with $Bi_2O_3-SiO_2$ glasses in order to reduce the evaporation of components. The sinterbility evaporation of components phase formation and microstructure were evaluated depending on the amount of $Bi_2O_3-SiO_2$ glass addition. Two probe A. C conductivity measurement was subjected to all the specimens and the result was discussed on the possible substitution of $Bi^{3+}$ for $Zr^{4+}$ and interistial $Si^{4+}$ in the fluorite structure of zirconia crystal there-upon the possible change in the capability of oxygen transference within the material. It was found that the addition of $Bi_2O_3$ could improve the sinterbility of material very much while not so much.oxygen sensing material suitable for relative low temperature firing.

• Human Ecology Research
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• v.52 no.2
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• pp.189-198
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• 2014

The purpose of this study was to examine the effects of the We Start center visiting intervention program on the positive changes in the developmental areas and literacy interests of young children from low-income families. The subjects were 195 young children (109 in the experimental group, M=71.7 months; 86 in the control group, M=73.3 months) living in We Start areas (Ansan, Gwangmyeong, and Suwon cities) of Gyeonggi-do. The We Start center visiting intervention programs were conducted for 30-34 weeks in each city, and pre-tests and post-tests were conducted before and after the intervention programs. The instruments used were the developmental checklist and the literacy interests test The developmental checklist consisted of 7 domains (personality & sociality; language, reading, & writing; scientific thinking; mathematical thinking; arts; social learning; and physical development). The literacy interests test consisted of 2 factors (interest in literacy and interaction during activity). The scores on the developmental checklist showed positive changes in several domains (personality & social development; language, reading, & writing ability; scientific thinking; and social learning), but not in mathematical thinking, arts, and physical development. Second, the results of the literacy interests test showed positive effects on interaction during activity and the total score. In conclusion, the We Start center visiting program for young children from low-income families is an effective early intervention program to end the intergenerational transference of poverty in Korea.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.123-132
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• 1999

This paper describes a research work of developing computer-aided design of lead frame, semiconductor, with blanking operation which is very precise for progressive working. Approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from pasticity theories, experimental results and the empirical knowledge of field experts. This system has been written in AutoLISP on the AutoCAD using a personal computer and in I-DEAS Drafting Programming Language on the I-DEAS Master Series Drafting with Workstation, HP9000/715(64). Transference of data between AutoCAD and I-DEAS Master Series Drafting is accomplished by DXF(drawing exchange format) and IGES(initial graphics exchange specification) methods. This system is composed of five modules, which are input and shape treatment, production feasibility check, strip-layout, data-conversion and die-layout modules. The process planning and Die design system is designed by considering several factors, such as complexities of blank geometry, punch profiles, and the availability of a press equipment and standard parts. This system provides its efficiecy for strip-layout, and die design for lead frame, semiconductor.

• Child Health Nursing Research
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• v.17 no.2
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• pp.74-83
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• 2011

Purpose: The purpose of this study was to develop a child health care protocol for teachers in child day care centers. Methods: The ADDIE model with 10 Kid Keys was applied to develop this child health care protocol. All contents were developed through content validity test by 7 professionals and need assessment and evaluation by child day care center teachers. Results: This protocol consisted of 10 keys, as follows: "Health Examination/Growth & Development", "Practice of Health Life", "Management of Communicable Disease", "Negligent Accident", "Coping with Emergency and Transference", "Child Abuse", "Nutrition/Obesity", "Quality Assurance of Staff", "Parent Education", "Guidance & Supervision of Child Day Care Centers". The contents contained goals, objectives, teaching content, suggested activities for children, writing forms related to each subject, and self-evaluation sheet. Conclusion: This protocol can be practical and effective for child health care in child day care centers and it is hoped that it will be utilized in more child day care centers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.4
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• pp.27-34
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• 2005

The paper discussed on the stability of cantilevered pipe conveying fluid subjected to distributed follower force. Governing equations of motion are derived by extended Hamilton's principle, and the numerical scheme using finite element method is applied to obtain the discretized equations. The critical flow velocity as a function of the distributed follower force for the various mass ratio is determined. The flutter configurations of the pipes at the critical flow velocities are drawn graphically at every twelfth period to define the order of quasi-mode of flutter configuration The critical mass ratios, at which the transference of the eigenvalue branches related to flutter take place, are definitely determined. Also, the effect of damping on the stability of the system is considered.

• Journal of the Korean Ceramic Society
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• v.53 no.6
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• pp.635-640
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• 2016

Electrical behavior of AlN ceramics sintered with $Y_2O_3$ as a sintering aid has been investigated with respect to additional $TiO_2$ dopant. From the impedance spectroscopy, it was found that the grain and grain boundary conductivities have greatly decreased with addition of $TiO_2$ dopant. The $TiO_2$ dopant also increased the activation energy of the grain conductivity by about 0.37 eV; this increase was attributed to the formation of an associate between Al vacancies and Ti ions at the Al sites. Similarly, the electronic conductivity was reduced by $TiO_2$ addition. However, $TiO_2$ solubility in AlN grains was below the detection limit of typical EDX analysis. Grain boundary was clean, without liquid films, but did show yttrium segregation. The transference number of ions was close to 1, showing that AlN is a predominantly ionic conductor. Based on the observed results, the implications of using AlN applications as insulators have been discussed.

• Journal of Families and Better Life
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• v.29 no.4
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• pp.205-216
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• 2011

Unequal distribution of shares among children during intergenerational transference of assets has been prevalent in Korea. This study intends to examine whether parental contribution, in the form of a cash gift, is differentiated between the bride's side and the bridegroom's side at marriage and by age group. This pattern may also change according to the generation. Questionnaires were equally distributed to members of three previously delineated age groups: 20' s-30' s, 40's -50's, and 60's and above who are married or have been married at least once and reside in Seoul or Gyeonggi province. A total of 700 questionnaires were analyzed using SPSS and the data were sorted by age group. The results indicate an apparent difference between the husband's side and the wife's side in providing funding for housing at marriage in that a large portion of the funding is provided by the husband's side. Among various funding sources, a cash gift from the couple's parents appears to fund the largest portion of the total cost for housing and marriage. Results show that a cash gift from the couple's parents funds a larger portion of housing expenses for younger generations, a phenomenon that becomes more severe and apparent the younger the couple is.