• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.7
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• pp.1185-1192
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• 2003

Governing parameters for determination of the location of crack initiation and direction of crack initiation were investigated by performing fretting fatigue tests and analysis on Al 2024-T351. Fatigue tests were carried out using biaxial fatigue machine. It was shown that the dominant fatigue crack tended to initiate at the outer edge of one of the four bridge pads, growing at an angle beneath a pad, before turning perpendicular to the orientation of the axial load. Distribution of stresses generated during fretting fatigue loading along the interface was calculated by elastic FE simulation. It can be known that the location of crack initiation can be predicted by using the maximum tangential stress range. Futhermore, the crack initiation direction can also be predicted by a maximum tangential stress range.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.106-108
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• 2002

반도체 physical layout design rule이 작아짐에 따라 Proximity effect와 overlay가 Pattern 구현에 크게 영향을 미치고 있다. Metal layer와 contact의 부족한 overlay margin으로 overlay 불량이 발생하고, 감소한 space margin으로 인해 bridge와 같은 문제가 나타난다. 따라서, resolution을 향상시키고, 최소한의 overlay margin을 확보함으로써 미세 pattern의 구현을 가능하게 한다. 이를 위해 OPC와 attPSM 같은 분해능향상기술이 사용된다. 그러나 attPSM의 사용은 원하지 않는 pattern이 생성되는 sidelobe와 같은 문제가 발생한다. 따라서 serial image simulation올 통해 추출한 rule을 rule-based correction에 적용하여 sidelobe현상을 방지한다. 그리고 overlay margin 부족으로 나타나는 문제는 metal layer와 contact overlap되는 영역의 line edge를 확장하고, rule checking을 통해 최소한의 space margin을 확보하여 해결한다 따라서 overlay error를 rule-based correction을 사용하여 효과적으로 방지한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.171-174
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• 2007

During last 30 years, Korea economy has grown so fast and many leading-edge technologies ware introduced from the advanced countries. but this fast growth inevitably produced imperfect completion of infrastructures and caused man-made catastrophes like Sungsu Bridge and Sampoong Department Store. After the incidents, Korea Government and National Assembly established "The Special Law for Safety Maintenance of Infrastructures". According to this law, most of infrastructures must be inspected periodically. During last 10 years after the establishment of the law, many infrastructures were improved and the quality of construction was upgraded. However, important and weak-to-disaster infrastructures need to be watched continuously. Many monitoring technologies were developed and tested in the field. In this paper, the new research project "Establishment of Testbed of Safety Management Network for Main Infrastructures", funded by government, was introduced.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.123-124
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• 2009

This research is a part of the comprehensive research project to develop the optimized UHPC precast deck system applying to durable and cost-effective hybrid cable stayed bridge. Longitudinally prestressed ribbed section is proposed to make the best use of a advantage of the ultra high performance concrete and the design concept is presented to decide the sectional property.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1119-1124
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• 2004

Full depth precast concrete bridge deck system can be advantageously to reduce construction time, hence lowering the cost. This system has several significant design and construction component. To connect between the concrete slab and steel girder, precast deck has shear pocket. Post-tensioning tightens the joints and prevents any leakage though the joint. When post-tensioning is applied, stress concentration occurs in the edge of shear pocket. In this study, precast decks using four types of shear pocket is analyzed by F.E.M.

• Journal of Information Processing Systems
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• v.8 no.1
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• pp.101-118
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• 2012

Embedded products are becoming richer in features. Simulation tools facilitate low-costs and the efficient development of embedded systems. SID is an open source simulation software that includes a library of components for modeling hardware and software components. SID components were originally written using C/C++ and Tcl/Tk. Tcl/Tk has mainly been used for GUI simulation in the SID system. However, Tcl/Tk components are hampered by low performance, and GUI development using Tcl/Tk also has poor flexibility. Therefore, it would be desirable to use a more advanced programming language, such as Java, to provide simulations of cutting-edge products with rich graphics. Here, we describe the development of the Java Bridge Module as a middleware that will enable the use of Java Components in SID. We also extended the low-level SID API to Java. In addition, we have added classes that contain default implementations of the API. These classes are intended to ensure the compatibility and simplicity of SID components in Java.

• IE interfaces
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• v.7 no.3
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• pp.77-90
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• 1994

Recently, it has been widely conceived that Concurrent Enginering (CE) can provide a competitive edge for companies that have confronted with rapidly changing market requirements, such as shortening of product life-cycles, high quality and low cost products, diversity of customer demand, and so on. CE is generally recognized as a practice to bridge the gap between designing a product and other various life-cycle activities, such as manufacturing, assembly, testing, and maintenance, at an early stage of design. In this paper the concepts of CE is first overviewed, and many of its supporting tools are discussed. It is then proposed an architecture of a CE support system that can provide a unifying view of the tools. Finally, a case that has successfully implemented the concepts is presented.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.44.1-44.1
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• 2020

Hα jets of cool chromospheric plasma are protruding into the solar corona 10-100 Mm above the photosphere. The driving mechanisms of Hα jets have been widely studied for decades. However, the detailed process is still elusive. We observed shock signatures moving along a dark jet using 1.6 meter Goode Solar Telescope at Big Bear Solar Observatory. The first shock front of the jet shows sharp --- when it moves upward, while fuzzy and granulated when it moves downward. The jet itself extends upward when the second shock front of the jet reaches the top of the jet. We find abrupt EUV brightenings when the second shock front collides with the edge of the jet. The third front and the fouth front quasi-periodically. These phenomena might be the signs of the rebound shock waves triggered by p-mode wave leakages at the bottom of the jets. Our observation suggests that the jet can be triggered by the rebound shock waves generated by the p-mode waves leaked at the bottom of the jets.

• IMMUNE NETWORK
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• v.16 no.1
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• pp.52-60
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• 2016

Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that bridge innate and adaptive immune responses, thereby leading to immune activation. DCs have been known to recognize pathogen-associated molecular patterns such as lipopolysaccharides (LPS) and nucleic acids via their pattern recognition receptors, which trigger signaling of their maturation and effector functions. Furthermore, DCs take up and process antigens as a form of peptide loaded on the major histocompatibility complex (MHC) and present them to T cells, which are responsible for the adaptive immune response. Conversely, DCs can also play a role in inducing immune suppression under specific circumstances. From this perspective, the role of DCs is related to tolerance rather than immunity. Immunologists refer to these special DCs as tolerogenic DCs (tolDCs). However, the definition of tolDCs is controversial, and there is limited information on their development and characteristics. In this review, we discuss the current concept of tolDCs, cutting-edge methods for generating tolDCs in vitro, and future applications of tolDCs, including clinical use.

• Journal of the Korean Arthroscopy Society
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• v.13 no.2
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• pp.179-182
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• 2009

Purpose: Point fixation at the margin of the glenoid is a limitation of conventional arthroscopic stabilization using suture anchors, and does not afford sufficient footprint healing, especially in glenoid bone deficiency. So, we introduce an arthroscopic suture bridge transosseous-equivalent technique for bony Bankart lesions to avoid the technical disadvantage of point contact with anchor fixation and to improve mechanical stability through cross compression of the labrum. Surgical approach: The technique was adapted from the transosseous-equivalent rotator cuff repair technique using suture bridges, which improved the pressurized contact area and mean pressure between the tendon and footprint. After preparation of the glenoid bed by removal, reshaping, or mobilization of the bony lesion, two anchors (3.0 mm Biofastak, $Arthrex^{(R)}$, Naples, FL) were inserted into the superior and inferior portion of the bony Bankart lesion. Using a suture hook, medial mattress sutures were applied around the capsulolabral portion of the IGHL complex to obtain sufficient depth of glenoid coverage. A 3.5 mm pushloc anchor ($Arthrex^{(R)}$, Naples, FL) hole was made in the articular edge of the anterior glenoid rim. distal, suture bridge was applied, and proximal was inserted to mobilize the labrum in the proximal direction. This avoided the technical disadvantage of point contact with anchor fixation and decreased the level of gap formation through cross-compression of the labrum.