• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.3
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• pp.46-59
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• 1980

This study was conducted to obtain the most effective distribution of grain size and the optimum lime content for lime-soil stabilization. To achieve the aim, the change of consistency, the characteristics of compaction and unconfined compressive strength were tested by adding of 0, 4, 6, 8, 10 and 12 percent lime by weight for all soils adjusted by given ratios of sand to clay. The results obtained were as follows; 1. There was a tendency that the plasticity index of lime-soil mixture was decreased by increasing the amount of lime, whereas the liquid limit was varied irregularly and the plastic limit was increased. 2. With the addition of more lime, the optimum moisture content of lime-soil mixture was increased, and the maximum dry density was decreased. 3. The optimum lime content of lime-soil mixture was varied from soil to soil, and the less amount of small grain size, the less value of optimum lime content. 4. The optimum distribution of grain size for lime-soil mixture was in the soil, having the ratio of about 60 percent of cohesive clay and about 40 percent of sand by weight. 5. In the soil having fine grain size, the effect of curing appeared for long periods of time, whereas the increasing rate of unconfined compressive strength was great on the soil of coarse grain size in the earlier stage of curing period.

• Korean Journal of Applied Biomechanics
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• v.26 no.1
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• pp.83-92
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• 2016

Objective: This study aimed to compare differences in biomechanical factors according to distance changes in relation to approaches during a round of golf to obtain basic data on golf swings. Methods: The research subjects were 8 KPGA-affiliated professional golfers who performed approach shots that put a ball into a circle of 8 feet in diameter from distances of 30, 50, and 70 m. Data were collected by using six infrared cameras and a ground reaction force device, which were applied to calculate biomechanical factors by using Kwon3D XP. The calculated data were subjected to one-way ANOVA by using SPSS 20.0, with the significance level set at p value of 0.05. Results: Elapsed time, stance width, clubhead position variation, clubhead synthesis speed, and cocking angle significantly differed according to distance change during the approach swing. Clubhead speed was positively related with stance width and clubhead displacement. Ground reaction force significantly differed according to distance change during the approach swing. Factors before and after showed differences in other states, except in the impact state. Conclusion: In the present study, we drew several conclusions regarding biomechanical factors and ground reaction forces according to distance change in the approach swing of professional golfers. According to these conclusions, we suggest that distance control with swing range is more important than power control in maintaining the accuracy and consistency of golf swing and is the most important mechanism of golf swing.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.2
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• pp.11-23
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• 2014

The impact and adaption on agricultural water resources considering climate change is significant for reservoirs. The change in rainfall patterns and hydrologic factors due to climate change increases the uncertainty of agricultural water supply and demand. The quantitative evaluation method of uncertainty based on agricultural water resource management under future climate conditions is a major concern. Therefore, it is necessary to improve the vulnerability management technique for agricultural water supply based on a probabilistic and stochastic risk evaluation theory. The objective of this study was to analyse the uncertainty of water resources under future climate change using probability distribution function of water supply in agricultural reservoir and demand in irrigation district. The uncertainty of future water resources in agricultural reservoirs was estimated using the time-specific analysis of histograms and probability distributions parameter, for example the location and the scale parameter. According to the uncertainty analysis, the future agricultural water supply and demand in reservoir tends to increase the uncertainty by the low consistency of the results. Thus, it is recommended to prepare a resonable decision making on water supply strategies in terms of using climate change scenarios that reflect different future development conditions.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.181-183
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• 2006

UML 2.0의 시퀀스 다이어그램은 실시간 특성을 표기할 수 있는 표기법이 추가됨으로써 시간의 엄격성이 중요하게 여겨지는 임베디드 소프트웨어의 행위를 보다 정확하고 상세하게 모델링 할 수 있게 되었다. 시퀀스 다이어그램은 전체 시스템의 부분적인 행위를 기술하여 같은 행위가 여러 다이어그램에 걸쳐서 기술되어지므로 이들 다이어그램들은 서로 일관성을 가져야 하는데 복잡한 시스템에서 일관성을 검사하는 것은 어려운 일이다. 본 논문에서는 행위 모델을 표현하는 시퀀스 다이어그램과 다른 다이어그램에 기술된 실시간 특성들의 일관성을 자동으로 검사할 수 있는 방법을 제안한다. 먼저 서로 다른(inter) 다이어그램들 사이의 시간적인 일관성을 유지하기 위한 제약사항을 파악하여 정의한다. 그리고 모델을 구성하는 인스턴스들에 대한 제약사항을 OCL로 기술하는데 이는 UML 2.0이 발표되면서 모델의 의미를 정확하고 상세하게 표현할 수 있는 메타 모델과 그들의 연관관계가 추가되고 명확하게 정의됨에 따라 가능하게 된 것이다. 이렇게 OCL로 정형화되어 기술된 식은 UML 2.0 메타 모델을 이용한 어느 모델에나 적용 가능하며 모델의 문제점을 발견하고 정확한 모델을 구축하도록 도와준다.

• Journal of Families and Better Life
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• v.21 no.3
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• pp.15-28
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• 2003

The purpose of this study was to develop a family functioning scale that is suitable for Korean families. The data for this study were obtained from a survey on a sample of 350 mothers of school-age children, who were living in Seoul, Kyunggi-do, and other cities of Korea. The major findings ate as follows; 1) Through the item discrimination test, 63 of the 77 items were found to be significant, thus deemed acceptable. The level of discrimination indices of the 63 items ranged from .38 to .84. 2) A factor analysis was conducted on the 63 items. Six different factors (Emotional Support, Family Intimacy, Respect for Autonomy, Communication, Family Rules, Time Spent Together) emerged for 37 items. The six factors accounted for 56.51% of total variance. 3) A multiple regression analysis was conducted to reduce the number of items, and the final 36 items were selected for the Family Functioning Scale. 4) The reliability measured by the internal consistency of the 36 items was high (Cronbach's a =.93). 5) The Family Functioning Scale was found to have a significant correlation with FACESIII(r=.80) as well as with FAD(r=.78).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.71-74
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• 2005

The viscosity of high-flowability paste is very high compared to normal concrete for the low water-binder ratio(W/B). Therefore, high-flowability concrete is positively necessary to high-range water reducing agent. High-Flowability paste can make much higher fluidity with no occurrence of segregation, by its higher viscosity and lower yield value than normal concrete. The flowability of high-flowability paste must be evaluated not only by convention consistency test such as slump test but also by the base of the rheological properties of the fresh concrete. The purpose of this study is to analyze the fluidity of high-flowability paste according to the addition ratio of the Melamine Sulphonate high-range water reducing agent.; high-flowability paste is considered as Bingham plastic fluid with the rheology parameters of the plaste viscosity and yield value.

• Korean Journal of Child Studies
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• v.37 no.1
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• pp.7-16
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• 2016

Objective: It aimed at proposing the Korean Journal of Child Studies' strategy to be promoted to international journal based on the style and format of scholarly journals and journal metrics. Methods: The review of the journal in not only print version, but also an online version was done from the perspective of style and format. The total citation and impact factor were manually calculated from Web of Science Core Collection. Results: More professional level manuscript editing is required for maintaining the consistency of the style and format. The verso page and back matters should be improved to international level. Journal homepage should be reconstructed by adopting digital standards for the journal, including journal article tag suite, CrossMark, FundRef, ORCID, and text and data mining. To become an international journal, transformation into English journal and deposition to PubMed Central is mandatory. Conclusion: Since the editor's and society members' performance is top-notch, it will be possible to promote the journal up to international level soon. Society should guarantee the term of editor for enough time and support her with full cost and complete consent.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.4
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• pp.321-327
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• 2011

This paper proposes an equipment and an algorithm for modeling the magnetic force of electromagnets in magnetic levitation systems. We assume that the magnetic force model is represented in terms of a 2D lookup table. The 2D lookup table is constructed by applying noncausal filtering and interpolation to data measured by the proposed modeling equipment. The proposed modeling equipment is designed such that it can measure the magnetic force exerted on the levitation object while it changes the voltage applied to the electromagnet and position of the levitation object. The algorithm of making a 2D lookup table has two stages. The data measured by the proposed modeling equipment is smoothed by a noncausal filter and then the 2D lookup table is obtained by interpolating filtered data. The proposed modeling method has advantages of time-saving, model consistency, and chance of automation for mass production. We show the validity of proposed method through control experiments.

• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.95-105
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• 1999

When superplasticizer is added to manufacture flowing concrete, the base concrete usually needs the adjustment to assure the sufficient fines contained to obtain flowable consistency without excessive bleeding or segregation. However, this may not only increase the cost, but also cause inconvenience in producing the base concrete. In this paper, the experiments are performed on normal base concrete to achieve a segregation-reducing flowing concrete by adding superplasticizer mixed with viscosity agents and AE admixtures. Three kinds of superplasticizer and two kinds of viscosity agent are selected. According to the results, with regard to the performance and cost of the admixtures, melamine type superplasticizer combined with the PEO viscosity agent and AE admixtures at the ratio 1:0.28:0.001 can acquire good quality and reduce the cost in producing the flowing concrete. With proper addition of combined superplasticizer, even though water to cement ratios of the base concrete are different, the segregation-reducing flowing concrete could be also achieved without reproportioning of the base concrete. However, it would be more desirable if the superplasticizer could be adjusted, before it is put into the practical use in order not to cause some other problems, such as rapid rate of slump loss and retarding of setting time.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.40.1-40.1
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• 2014

We have classified barred galaxies for 418 RC3 sample galaxies within z < 0.01 from SDSS DR7 using the visual inspection, ellipse fitting method and Fourier analysis. We found the bar fraction to be ~60%, 43% and 70% for each method and that the ellipse fitting method tends to miss the bar when a large bulge hides the transition from bar to disk in early spirals. We also confirmed that the Fourier analysis cannot distinguish between a bar and spiral arm structure. These systematic difficulties may have produced the long-time controversy about bar fraction dependence on Hubble sequence, mass and color. We designed a new method to fine bars by analyzing the ratio map of bar strength in polar coordinates, which yields the bar fraction of ~27% and ~32% for SAB and SB, respectively. The consistency with visual inspection reaches around 70%, and roughly 90% of visual strong bar are classified as SAB and SB in our classification. Although our method also has a weakness that a large bulge lowers the value of bar strength, the missing bar fraction in early spirals is reduced to the level of ~1/4 compared to the ellipse fitting method. Our method can make up for the demerits of the previous automatic classifications and provide a quantitative bar classification that agrees with visual classification.