• Composites Research
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• v.23 no.4
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• pp.7-13
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• 2010

A volume integral equation method (VIEM) is introduced for the solution of elastostatic problems in an unbounded isotropic elastic solids containing interacting multiple anisotropic inclusions subject to remote uniaxial tension. The method is applied to two-dimensional problems involving long parallel cylindrical inclusions. A detailed analysis of stress field at the interface between the matrix and the central inclusion is carried out for square and hexagonal packing of the inclusions. Effects of the number of anisotropic inclusions and various fiber volume fractions on the stress field at the interface between the matrix and the central inclusion are also investigated in detail. The accuracy of the method is validated by solving the single inclusion problem for which solutions are available in the literature.

• Water Engineering Research
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• v.6 no.2
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• pp.49-61
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• 2005

This paper presents the numerical study to examine characteristics of fluid flow and solute transport in a rough fracture subject to effective normal stresses. The aperture distribution is generated by using the self-affine fractal model. In order to represent a nonlinear relationship between the supported normal stress and the fracture aperture, we combine a simple mechanical model with the local flow model. The solute transport is simulated using the random walk particle following algorithm. Results of numerical simulations show that the flow is significantly affected by the geometry of aperture distribution varying with the effective normal stress level while it is slightly affected by the fractal dimension that determines the degree of the fracture surface roughness. However, solute transport is influenced by the effective normal stress as well as the fracture surface roughness.

• English Language & Literature Teaching
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• v.15 no.4
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• pp.109-136
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• 2009

This study investigates English medium instruction (EMI) in an institution of higher education in Seoul, Korea to see whether this course creates cultural correction (reproduction of inequitable relations of power in EMI settings) or cultural continuity (opportunities for transporting students into a third space and enabling them to explore cultural diversity and to create new knowledge for themselves). A single site where EMI is carried out, a class on fairy tales and child education taught by a native English speaking professor, was chosen because it was hypothesized that the professor would display some of her unconscious dominant cultural orientation. The results of the study show that there more cases of cultural correction than there were of cultural continuity. Cases of cultural correction included lack of knowledge about the local context, fixing Korean classroom discourse as if it were American classroom discourse, and reproducing orientalism in the local educational setting. Cases of cultural continuity included using comparison to consider the cultural reality of the milieu, creating new knowledge for the local milieu, and learning as a dynamic ongoing process. Implications of this research are discussed including the important realization that EMI should be managed by subject specialists who are trained in language education and have knowledge of the students' needs and discourse in the L1 and in the local context.

• Journal of Ecology and Environment
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• v.41 no.5
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• pp.145-151
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• 2017

Background: Conventional bird observation methods are line survey or point count method by bare eyes or through binoculars or telescopes. But in this study, the possibility of monitoring waterbirds using drones beyond the conventional research methods was explored. It also describes the direction of producing and accumulating images of waterbird habitats as a method to efficiently determine changes in waterbird habitats. Results: From the study, it was concluded that waterbird monitoring using drones was a new monitoring technique which could be applied to the field and 26 kinds of waterbirds were observed. In the case of a drone with a single lens, it was difficult to identify objects because the size of the subject was too small at a certain altitude. In this case, zoom lens can be an alternative. It has also been verified that image analysis software can be used to accumulate images of waterbird habitats. Conclusions: If various kinds of advanced drones and cameras are used, it would be possible to monitor larger areas including the areas that are difficult for human access and to observe more waterbirds and wider habitats.

• Child Health Nursing Research
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• v.11 no.4
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• pp.444-455
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• 2005

Purpose: This study examined the efficacy of parent training interventions to facilitate social reciprocity and language development in children with autism. Methods: The social interaction behaviors of mothers and children over time were compared using single subject design experimentation methodology. five children who were diagnosed with autism and their mothers participated in the study. The participants were recruited from U city, Korea. The mothers were trained using training videotapes and demonstrations on how to facilitate social interaction with their children as well as promoting language development. following the training, data were collected three times per week by video taping mother-child interaction in their homes. Results: Four of the five mothers demonstrated increases in the use of imitation with animation and expectant waiting after the intervention compared to the baseline sessions; the children demonstrated noticeable increases in the use of initiation of interaction, vocalizations, and verbal production after their mothers received the training intervention. Conclusion : Results of this study demonstrate the efficacy of mother training to improve social interactions of children with autism. Additional important information can be gained by replicating this study with more participants and comparing intervention and control groups. Clearly, this intervention shows promise and has implications far clinical practice.

• Steel and Composite Structures
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• v.22 no.3
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• pp.589-611
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• 2016

The primary objectives of this research are to investigate the energy factor response of steel moment resisting frame (MRF) systems equipped with fuses subject to ground motions and to develop an energy-based evaluation approach for evaluating the damage-control behavior of the system. First, the energy factor of steel MRF systems with fuses below the resilience threshold is derived utilizing the energy balance equation considering bilinear oscillators with significant post-yielding stiffness ratio, and the effect of structural nonlinearity on the energy factor is investigated by conducting a parametric study covering a wide range of parameters. A practical transformation approach is also proposed to associate the energy factor of steel MRF systems with fuses with classic design spectra based on elasto-plastic systems. Then, the energy balance is extended to structural systems, and an energy-based procedure for damage-control evaluation is proposed and a damage-control index is also derived. The approach is then applied to two types of steel MRF systems with fuses to explore the applicability for quantifying the damage-control behavior. The rationality of the proposed approach and the accuracy for identifying the damage-control behavior are demonstrated by nonlinear static analyses and incremental dynamic analyses utilizing prototype structures.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.723-729
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• 2012

Spring-like leg models have been employed to explain various dynamic characteristics in human walking. However, this leg stiffness model has limitations to represent complex motion of actual human gait, especially the behaviors of each lower limb joint. The purpose of this research was to determine changes of total leg stiffness and lower limb joint stiffness with gait speed in knee osteoarthritis. Joint stiffness defined as the ratio of the joint torque change to the angular displacement change. Eight subjects with knee osteoarthritis participated to this study. The subject walked on a 12 m long and 1 m wide walkway with three sets of four different randomly ordered gait speeds, ranging from their self-selected speed to maximum speed. Kinetic and kinematic data were measured using three force plates and an optical marker system, respectively. Joint torques of lower limb joints calculated by a multi-segment inverse dynamics model. Total leg and each lower limb joint had constant stiffness during single support phase. The leg and hip joint stiffness increased with gait speed. The correlation between knee joint angles and torques had significant changed by the degree of severity of knee osteoarthritis.

• The Journal of Advanced Prosthodontics
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• v.13 no.3
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• pp.172-179
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• 2021

Purpose. This intra-patient retrospective study of up to 10 years evaluated the clinical success and risk factors of 6- and 8-mm long implants and their respective prostheses. Materials and Methods. The sample consisted of patients treated at a Military Polyclinic dental service, who received both 6- and 8-mm long tissue level implants in the posterior region of the same arch. Data were collected from the dental charts, clinical and radiographic exams, self-report of sleep bruxism, measurement of maximum occlusal force, and clinical crown-to-implant (C/I) ratio. Data were analyzed by descriptive and inferential statistics with univariate and hierarchical multivariate models, at the 0.05 significance level. Results. The 30 patients (27 women) had 85 implants and 83 prostheses. Two implants were lost before prosthesis installation (implant survival: 97.6%). Ten events of prosthetic complication (screw tightening loss) occurred in five patients (success rate: 87.9%) in a single moment. Only the variable C/I ratio had a significant effect for repairable prosthesis complication (P<.05). Conclusion. The results suggest that 6- and 8-mm long implants have similar long-term clinical success for implants and prostheses.

• Journal of Digital Contents Society
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• v.18 no.1
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• pp.35-46
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• 2017

The purpose of the study was to review the recent literature on applying augmented reality based educational contents for students with autism spectrum disorders and to identify research trends and implications. The search procedures through the Web-database system were implemented to find the proper research and a total of 12 studies were included in this review. The results indicated that most of subjects were elementary school-age children, also single subject design was mostly implemented. Mobile devices were used mostly for augmented reality, and most of data collection methods was behavioral observation. Results founded several contents types: objects manipulation, manipulation for self-modeling, on-site problem solving program, and location-based learning guide. Additionally, the results indicated that the educational effectiveness was the improvements of social behaviors, play and imitation behaviors, and emotion recognition. Furthermore, considerations to develop and apply augmented reality based educational contents for students with autism spectrum disorders were suggested.

• Korean Journal of Child Studies
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• v.33 no.6
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• pp.187-205
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• 2012

In this study, 150 previous studies of young children's challenging behavior, conducted over the past 10 years, from 2003 to 2012, were selected. These studies were in relation to young children both with and without disabilities, and they were thus used for the purposes of comparative analysis. The major findings are as follows. First, research on challenging behavior not only of young children with disabilities but also of those without disabilities has been an increasing trend from 2008. While most studies of those without disabilities were based on observations by parents or teachers using a variety of tools, studies regarding those with disabilities mainly used single-subject research methods using an operational definition. Second, the bulk of the studies of young children without disabilities were focused on interaction between various children's internal variables and a variety of parent-related variables related to the occurrence of challenging behavior. In comparison, studies of young children with disabilities were focused excessively on direct intervention after the occurrence of problems. Regarding those without disabilities, the interaction between children's temperament, internal variables, and their mothers' parenting behavior, external variables were the main areas of interest for these researchers. There is clearly a growing need for more active research aimed at the prevention of challenging behavior. Challenging behavior in early childhood has an influence not only on each child's present and future academic achievement levels and their quality of life but also on the quality of instruction in classroom available to all children.