• Child Studies in Asia-Pacific Contexts
• /
• v.5 no.1
• /
• pp.51-62
• /
• 2015

This study examined the role of ethnicity and extended family relationship in the longitudinal patterns of unmarried resident fathers' engagement with young children in the U.S. Using three waves of panel data from the Fragile Families and Child Wellbeing Study (FFCWS), data obtained from 292 respondents were analyzed by the Linear Mixed Effects Regression (LMER) method. Findings suggested that Black unmarried resident fathers exhibited more engagement with their infants at age one than their White counterparts did, but the initial difference reversed by age five as a result of decreasing engagement among Black fathers over time and comparatively increasing engagement among Whites. Results also suggested that Black unmarried resident fathers with a high relationship level with their extended family members exhibited less engagement with their infants than Black fathers with a low relationship level, but the initial difference reversed by age five as a result of decreasing engagement among Black fathers with a low relationship level over time and comparatively increasing engagement among Black fathers with a high relationship level.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.14 no.2
• /
• pp.16-23
• /
• 2018

In order to investigate the ways to enhance the seismic performance of APR1400 seismic fragile equipment by direct design changes, four equipment such as Reactor Vessel Support, Integrated Head Assembly, Remote Shutdown Console, and Pressurizer are reviewed using information of the main dimensions, seismic stress evaluation results, design FRS, etc. in this paper. In addition to the direct reinforcement of equipments, the feasibility of seismic isolation for the safety related cabinet is also investigated and the actual adaption plan of a commercial spring-damper system is briefly reviewed.

• The Journal of Korea Robotics Society
• /
• v.16 no.1
• /
• pp.35-40
• /
• 2021

As the robot industry develops, industrial automation uses industrial robots in many parts of the manufacturing industry. However, rigidity-based conventional robots have a disadvantage in that they are challenging to use in environments where they grab fragile objects or interact with people because of their high rigidity. Therefore, researches on soft robot have been actively conducted. The soft robot can hold or manipulate fragile objects by using its compliance and has high safety even in an atypical environment with human interaction. However, these advantages are difficult to use in dynamic situations and control by the material's nonlinear behavior. However, for the soft robot to be used in the industry, control is essential. Therefore, in this paper, real-time PD control is applied, and the behavior of the soft actuator is analyzed by providing various waveforms as inputs. Also, Iterative learning control (ILC) is applied to reduce errors and select an ILC type suitable for soft actuators.

• 대한예방의학회:학술대회논문집
• /
• 2001.04a
• /
• pp.78-78
• /
• 2001

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2005.05a
• /
• pp.120-120
• /
• 2005

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2005.05a
• /
• pp.65-65
• /
• 2005

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.7
• /
• pp.4516-4521
• /
• 2014

Digital watermarking for digital image authentication and integrity schemes are based on fragile watermarking and can detect any modifications in a watermark embedded image by comparing the embedded watermark with the regenerated watermark. Therefore, the digital watermark for image authentication and integrity should be erased easily when the image is changed by digital image processing, such as scaling or filtering etc. This paper proposes an effective tamper detection scheme for digital images. In the proposed scheme, the original image was divided into many non-overlapping $2{\times}2$ blocks. The digital watermark was divided into two LSB of each block and the image distortion was imperceptible to the human eye. The watermark extraction process can be used to determine if the watermarked image has been tampered. The experimental results successfully revealed the effectiveness of the proposed scheme.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.3
• /
• pp.352-358
• /
• 2020

In this study we investigated the immune effects of oral administration of anionic macromolecules extracted from Codium fragile (CFAM) and red ginseng extract mixture on the peritoneal macrophage cells in immune-suppressed mice. Cyclophosphamide (CY) induces the immune-suppressed condition. CY-treated mice were orally fed with different concentrations of CFAM supplemented with red ginseng extract and the peritoneal macrophages collected. CY treatment significantly decreased the immune activities of peritoneal macrophages, compared to the normal mice. The administration of CFAM mixed with red ginseng extract significantly boosted the viability of macrophage cells and nitric oxide production of peritoneal macrophages. Further, the oral administration of CFAM mixed with red ginseng extract up-regulated the expression of iNOS, COX-2, and TLR-4 as well as cytokines such as IL-1β, IL-6, TNF-α, and IFN-γ more than the red ginseng-treated group. This study showed that CFAM enhanced the immune activity of red ginseng extract in the peritoneal macrophage cells of immune-suppressed mice. Furthermore, CFAM might be used as a co-stimulant of red ginseng extract through the regulation of macrophage cells for the enhancement of human health and immunity.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.38 no.7
• /
• pp.595-600
• /
• 2014

The characteristics of kinetic energy transfer during a collision between a rigid target particle on a surface and a fragile bullet particle moving at a high velocity were analyzed using molecular dynamics simulation. Bullet particles made of $CO_2$ were considered and their size, temperature, and velocity were varied over a wide range. The fraction of kinetic energy transferred from the bullet particle to the target particle was almost independent of the former's size or velocity; however, it was sensitively dependent on its temperature, which can be attributed to the change in the bullet rigidity with temperature. This fraction was nearly twice as high for $CO_2$ bullets as for Ar bullets. This result explains the reason for the more superior cleaning performance of $CO_2$ bullets than Ar bullets with regard to contaminants in the 10 nm size range.

• Journal of Korea Multimedia Society
• /
• v.12 no.4
• /
• pp.559-571
• /
• 2009

This paper presents a concurrent watermarking scheme with both robustness and fragileness for copyright protection and authentication of 3D animation contents. In a 3D animation model, the proposed scheme embeds not only robustly the watermark into geometry node for copyright protection but also fragilely the watermark into position and orientation interpolators for content authentication. This paper names the former as the robust geometry watermarking and the latter as the fragile interpolator watermarking. The proposed scheme performs independently these watermarkings for satisfying at one time the robustness and the fragileness of 3D animation model. From experimental results, we verified that the watermark embedded by the geometry watermarking has the robustness against many attacks from 3D public editing tools and also the watermark embedded by the interpolator watermarking has the fragileness against the same attacks.