• Journal of Animal Science and Technology
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• v.61 no.6
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• pp.324-332
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• 2019

This study aimed to identify the causality between climatic and soil variables affecting the yield of Italian ryegrass (Lolium multiflorum Lam., IRG) in the paddy field by constructing the pathways via structure equation model. The IRG data (n = 133) was collected from the National Agricultural Cooperative Federation (1992-2013). The climatic variables were accumulated temperature, growing days and precipitation amount from the weather information system of Korea Meteorological Administration, and soil variables were effective soil depth, slope, gravel content and drainage class as soil physical properties from the soil information system of Rural Development Administration. In general, IRG cultivation by the rice-rotation system in paddy field is important and unique in East Asia because it contributes to the increase of income by cultivating IRG during agricultural off-season. As a result, the seasonal effects of accumulated temperature and growing days of autumn and next spring were evident, furthermore, autumnal temperature and spring precipitation indirectly influenced yield through spring temperature. The effect of autumnal temperature, spring temperature, spring precipitation and soil physics factors were 0.62, 0.36, 0.23, and 0.16 in order (p < 0.05). Even though the relationship between soil physical and precipitation was not significant, it does not mean there was no association. Because the soil physical variables were categorical, their effects were weakly reflected even with scale adjustment by jitter transformation. We expected that this study could contribute to increasing IRG yield by presenting the causality of climatic and soil factors and could be extended to various factors.

• Journal of Science Education
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• v.38 no.2
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• pp.454-469
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• 2014

Teachers' presuppositions of nature of science, scientific causality, and nature are unconsciously constructed through interactions with his or her physical and social environment everyday and it began even before they were in any formal education. It directly influences their teaching later. Thus, this study examined what comprehensive presuppositions in nature of science, scientific causality, and nature are held by in-service secondary science teachers. For the study, Q-methodology was used. Q-sorting was done on 81 statements from three instruments: Nature statements, the Test of Preferred Explanations, and the Nature of Science Scale with twelve in-service science teachers. Teachers sorted the statements along a presented agreement scale of their viewpoint and the collected data was analyzed using recommended procedures for Q-sorts in order to group teachers with similar views. As a result, ten participants were placed in five factors based on their presuppositions of science, scientific causality, and nature and distinctive features of each factor were discovered. In addition, the study confirmed that presuppositions of science, scientific causality, and nature are interrelated. This study method will be helpful to discover more relationships regarding teachers' various viewpoints further.

• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.109-115
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• 2016

This study intended to testify the causality among three variables such as accident, depression and cognitive failure of the train drivers. For this purpose, two research models were suggested. Model 1 hypothesized the causality among three variables as 'depression ${\rightarrow}$ cognitive failure ${\rightarrow}$ accident'. On the other hand, model 2 hypothesized the causality among three variables as 'accident ${\rightarrow}$ depression ${\rightarrow}$ cognitive failure'. Results based on AMOS using 416 train drivers' questionnaire showed that model 2 is more valid than model 1. The statistical result of model 1 showed that depression has a positive effect on cognitive failure, however no significant relationship between depression and accident as well as between cognitive failure and accident. In model 2, the result showed that the accident has a positive effect on cognitive failure mediated by depression. This result suggests the necessity for establishment of countermeasures to mitigate mistake and cognitive failure caused by train drivers in a wider context, considering the causality between accident and depression.

• Child Health Nursing Research
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• v.6 no.3
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• pp.291-304
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• 2000

The purpose of this study was to explore the health and illness concepts of hospitalized preschoolers. The subjects were 52 hospitalized preschoolers from 3 to 6 grade in one general hospital. Data were collected through semistructured interviews by author. this study was conducted from Mar 2, 2000 to Jun. 30, 2000. Data were coded and categorized by content analysis. The results were as follows : 1. Hospitalized preschoolers's answers about health concepts were coded and then classificated to 7 categories(physical well-being, food, powerfulness, exercise, obedience to authority, cleanliness, sleep.) 2. Hospitalized preschoolers's answers about health behavior to maintenance health were coded and then classificated to 8 categories (food, obedience to authority, treatment, exercise, cleanliness, powerfulness, sleep, psychological stability). 3. Hospitalized preschoolers's answers about prevention of illness were coded and then classificated to 9 categories(food, treatment, obedience to authority, powerfulness, emotional stability, psychological stability, exercise, physical well-being, ability of social adaption). 4. Hospitalized preschoolers's answers about cause of illness were coded and then classificated to 3 categories(illness, trauma, food). 5. Hospitalized preschoolers's answers about treatments of illness were coded and then classificated to 9 categories(treatment, rest, emotional stability, sleep, psychological stability, food, obedience, exercise, powerfulness). 6. The levels of health and illness concepts in this sample were higher than those of the physical causality.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.156-162
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• 2003

The shock absorber is a part having a direct influence on the ride comfort, stability and dynamic load prediction of a vehicle. Thus, a rationally modeled shock absorber should be required in the dynamic analysis of vehicles. This thesis presents a modified model, based on Worden's hyperbolic tangent function, in order to fit experimental data on the velocity-damping force of a shock absorber. The hyperbolic tangent function correctly indicates the characteristics of a shock absorber, and has the advantage of containing physical causality. To evaluate the method, comparative evaluations of the linear model, the 5th polynomial model and Worden's model were carried out. The function presented in this paper is not only simple but also makes it possible to estimate the function coefficients easily and visually. In addition, it has the advantage of containing physical causality. Lastly, it effectively models the damping force of a shock absorber.

• Journal of the Korea Society for Simulation
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• v.4 no.2
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• pp.31-40
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• 1995

A hybrid simulation model consists of real physical entities as well as simulated ones. It also contains logical processes for decision making for each operation units, a group of the entities. During the execution of such simulations, the physical and the logical processes consume real clock time while the activity durations of the simulated ones are generated. Due to the inherent chracteristics of the subjects of the communication channels. Since one can not undo an real event already taken place, the traditional central clock approach is used for the synchronization of the events(Kim[6]). However, there are still chances of causality errors due to the randomness in the communication delays. This error is not found in the distributed pure simulations. This paper explains the error in details and proposes a prevention scheme that is simple to implement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1479-1482
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• 2003

The shock absorber is a part having a direct influence on the ride comfort, stability and dynamic load prediction of a vehicle. Thus, a rationally modeled shock absorber should be required in the dynamic analysis of vehicles. This thesis presents a modified model, based on Worden's hyperbolic tangent function, in order to fit experimental data on the velocity-damping force of a shock absorber. The hyperbolic tangent function correctly indicates the characteristics of a shock absorber. and has the advantage of containing physical causality. To evaluate the method, comparative evaluations of the linear model. the 5th polynomial model and Worden's model were carried out. The function presented in this paper is not only simple but also makes it possible to estimate the function coefficients easily and visually. In addition, it has the advantage of containing physical causality. Lastly, it effectively models the damping force of a shock absorber.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.9
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• pp.1414-1421
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• 1997

This paper examines the physics and mechanics governing the dynamic interaction between physical systems and suggests the four structures of bond graph prototypes, considered as a general model that can promise their dynamic behavior physically resonable. The bond graph prototypes originating from the paper are more realistic junction structures than those used to model dynamic systems conventionally by bond graph standards in whether physical constraints are involved or not when the energy exchange between two dynamic components arises. It is shown that the bond graph prototypes are dynamic or energetic in their describing equations compared to the bond graph standards, and connectivity and causality are properties of dynamic systems upon which the steps developed in this paper for the bond graph prototypes are wholly based and their definitions an concepts are highly emphasized all through the paper.

• Korean Journal of Child Studies
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• v.28 no.4
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• pp.245-264
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• 2007

This study analyzed physical knowledge displayed in the utterances of 10 Korean children 23 - 76 months of age. Utterances were blocked into four-month time periods, except the first two months and classified into 5 categories including properties of physical objects and materials, friction, buoyancy, gravity, and the motion of physical objects. All five types of physical expressions were found in the data of the earliest period the percent age of the properties and motion was higher than the percent of friction, buoyancy, and gravity. Data suggested two transitional points of change in physical knowledge : 2-year-old's descriptions were based only on perceptually salient physical features 3- to 4-year-olds described only end-state results while children older than 4 included systematic causality.

• Journal of Korean Academy of Nursing
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• v.22 no.2
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• pp.143-156
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• 1992

This descriptive study explored the health and illness concepts of preschoolers to provide understanding on which to build research. The subjects were convenience sample three to six year of age attending one art institute in Cheju city. Data were collected through semistructured interviews by author, Children were asked to draw two figures, one healthy and one ill persons. The drawings were not analysed to grasp the meaning as in a projective technique, but only to relate to their response. Data were coded and categorized by content analysis. The results of this study are summarized as follows : 1) Three year olds responded with some unrelated answers but well to questions related to their experiences of illness ; older participants answered questions related health and illness concepts more easily. Generally the levels of subjects' responses did not differ according to age and sex. 2) Preschoolers' answers about the cause, treatment and prevention of illness, and the meaning and promotion of health were coded and then classificated to 9 categories, (food, obedience to authoritys physical function, presence or absence of illness or symptoms, hygiene. treatment, traumatic injury, rest and germs). Food and obeidence to authority categories were most frequent responses the food category was associated with obeidence to authority because it seemed that the children follow the orders of their parents or other authority figures to eat or not to eat something This result was compatible with that of previous studies that preschoolers perceived illness as possible punishment for misbehavior. Participants except for one four year old boy did not suggest that germs cause illness. The children perceived themselves and their families as healthy even though they had symptoms of illness. 3) Preschoolers' health and illness concepts were. influenced by their experiences and related to their development that rules derived from authority and if not complied with, will bring punishment. These oonceptualizations may be the disparity that they perceived themselves and their families as healthy even though they were ill. A previous study by Perrin and Gerrity suggested that the level of children's illness concepts correlated with that of their physical causality and was lower than it. But the levels of health and illness concepts in this sample higher than those of the physical causality.