• Journal of the Korean institute of surface engineering
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• v.49 no.6
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• pp.507-512
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• 2016

Expensive silver powder is used to form electrodes in most IT equipment, and recently, many attempts have been made to lower manufacturing costs by developing powders with Ag-Ni or Ag-Cu core-shell structures. This study examined the sintering behavior of Ag-Ni electrode powder with a core-shell structure for silicon solar cell with high energy efficiency. The electrode powder was found to have a surface similar to pure Ag powder, and cross-sectional analysis revealed that Ag was uniformly coated on Ni powder. Each electrode was formed by sintering in the range of $500^{\circ}C$ to $800^{\circ}C$, and the specimen sintered at $600^{\circ}C$ had the lowest sheet resistance of $5.5m{\Omega}/{\Box}$, which is about two times greater than that of pure Ag. The microstructures of electrodes formed at varying sintering temperatures were examined to determine why sheet resistance showed a minimum value at $600^{\circ}C$. The electrode formed at $600^{\circ}C$ had the best Ag connectivity, and thus provided a better path for the flow of electrons.

• Journal of the Optical Society of Korea
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• v.13 no.1
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• pp.22-27
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• 2009

Target design study to improve the quality of an accelerated proton beam from the interaction of a high-intensity short pulse laser with an overdense plasma slab has been accomplished by using a two-dimensional, fully electromagnetic and relativistic particle-in-cell (PIC) simulation. The target consists of a thin core part and a thick peripheral part of equivalent plasma densities, while the ratio of the radius of the core part to the laser spot size, and the position of the peripheral part relative to the fixed core part were varied. The positive effects of this core-peripheral target structure could be expected from the knowledge of the typical target normal sheath acceleration (TNSA) mechanism in a laser-plasma interaction, and were apparently evidenced from the comparison with the case of a conventional simple planar target and the case of the transversal size reduction of the simple planar target. Improvements of the beam qualities including the collimation, the forward directionality, and the beam divergence were verified by detailed analysis of relativistic momentum, angular directionality, and the spatial density map of the accelerated protons.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.38 no.6
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• pp.82-92
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• 2001

This paper describes implementation of an embedded 32-Bit RISC core for portable communication/information equipment, such as cellular phones, PDA(Personal Digital Assistants), notebook, etc. The RISC core implements the ARM$\circled$V 4 instruction set, operates with typical 5-stage pipeline. It supports Thumb code to improve the code density, and uses the dynamic power management method of pipeline registers. It was modeled and simulated in RTL level using VHDL, and verified with ARMulator of ADS (Arm Developer Suite) and had average CPI of 1.44. The core is synthesized automatically using the cell library based on $0.6{\mu}m$ CMOS 1-poly 3-metal CMOS technology. It consists of about 41,000 gates and the clock frequency is expected to be above 45 MHz.

• Clinics in Shoulder and Elbow
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• v.26 no.2
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• pp.191-204
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• 2023

Avascular necrosis (AVN) of the humeral head is a rare, yet detrimental complication. Left untreated, humeral head AVN frequently progresses to subchondral fracturing and articular collapse. Cases of late-stage humeral head AVN commonly require invasive procedures including humeral head resurfacing, hemiarthroplasty, and total shoulder arthroplasty (TSA) to improve clinical outcomes. However, in cases of early-stage AVN, core decompression of the humeral head is a viable and efficacious short-term treatment option for patients with pre-collapse AVN of the humeral head to improve clinical outcomes and prevent disease progression. Several techniques have been described, however, a percutaneous, arthroscopic-assisted technique may allow for accurate staging and concomitant treatment of intraarticular pathology during surgery, although further long-term clinical studies are necessary to assess its overall outcomes compared with standard techniques. Biologic adjunctive treatments, including synthetic bone grafting, autologous mesenchymal stem cell/bone marrow grafts, and bone allografts are viable options for reducing the progression of AVN to further collapse in the short term, although long-term follow-up with sufficient study power is lacking in current clinical studies. Further long-term outcome studies are required to determine the longevity of core decompression as a conservative measure for early-stage AVN of the humeral head.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.123.1-123.1
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• 2010

The solid oxide fuel cell (SOFC) has attracted great deal of attention due to its high electrical efficiency, high waste-heat utilization, fuel flexibility, and application versatility. However, SOFC technology is still not matured enough to fulfill the practical requirements for commercialization. Therefore, all the research and development activities are mainly focused on a development of practically viable SOFCs with higher performance and better reliability. We were successful in fabricating high-performance anode-supported unit cells by employing hierarchically controlled multi-layered electrodes for both structural reliability and high performance. In addition, a novel composite sealing gasket made it possible to achieve excellent sealing integrity even with considerable surface irregularities in a multi-cell planar arrayed stack.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.313-315
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• 2006

Proper water management is important to achieve high performance and durability of Polymer electrolyte fuel cell (PEFC). Among various stack components, gas diffusion layer (GDL) is considered as a core part to determine the gas and water transportation in a cell. To optimize the water management, the changes of properties as well as basic properties of GDLs were investigated before and after clamping of colls. Thickness, electric conductivity, porosity, hydroppobicity etc. were characterized by the same criteria. The amount of residual water after cell operation also was compared by direct measuring of weight. Based on the amount of residual water the endurance on the freeze condition was evaluated.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.6
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• pp.92-96
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• 2003

Feul-Cell system consists of fuel reformer, stack and energy translator. Among these parts, stack is a core part which produces electricity directly. In order to set a stack module, fabrication of appropriate stack, design of water flow path in stack and control of coolant are needed. Especially, oater or air is used as a coolant to dissipate heat. The different temperature of each electric cell after cooling affects the performance of the stack. Therefore, it is necessary that the relationship between coolant hearing rate, width of stack, properties of stack, and the shape of water flow path must be understood. For the optimal design, the computational simulation by CFD-ACE has been conducted and the resulting database has been constructed.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.947-953
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• 2010

The KTX-Sancheon has been commercially operating on the high-speed line since March. 2. In order to verify the performance of high-speed train and core equipments such as current collection system, sophisticated tests and evaluating procedures should have been considering. In this paper, the load cell with a built-in strain-gauge which developed to improve measuring method of contact force between the pantograph and catenary system is introduced. The static test results of the load cell shows that its design is very suitable and applicable for the dynamic test and on-line test. After the test and evaluation of load cell's dynamic calibration with pantograph, we will be applied to test interaction characteristics between the pantograph and catenary system on the high-speed line.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1991.10a
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• pp.174-178
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• 1991

ATM, the core technology of BISDN, provides a high degree of flexibility with regard to varying bandwidth requirements for different services. In ATM networks, since users may exceed the traffic volume negotiated at the call setup, traffic from users may need to be monitored and enforced to comply with traffic parameters. The leakybucket mechanism is one of the typical traffic enforcement methods based on the use of transmission tokens for each cell. In this mechanism the major system parameters are size of input buffer, size of token pool, and token generation ratio. In order to represent ATM cell arrivals we assume a Poisson process. In this paper, a state transition analysis technique is used to study the cell loss rates for various values of system parameters.

• BMB Reports
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• v.51 no.3
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• pp.151-156
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• 2018

The Hippo signaling pathway controls nuclear accumulation and stability of the transcriptional coregulator YAP and its paralog TAZ. The activity of Hippo-YAP signaling is influenced not only by biochemical signals, but also by cell shape and mechanical tension transmitted through cell-cell junctions and cell-matrix adhesions. Data accumulated thus far indicates that the actin cytoskeleton is a key mediator of the regulation of Hippo-YAP signaling by means of a variety of biochemical and mechanical cues. In this review, we have outlined the role of actin dynamics and actin-associated proteins in the regulation of Hippo-YAP signaling. In addition, we discuss actin-mediated regulation of YAP/TAZ activity independent of the core Hippo kinases MST and LATS. Although our understanding of the link between Hippo-YAP signaling and the actin cytoskeleton is progressing rapidly, many open questions remain.