• Journal of Computing Science and Engineering
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• v.6 no.4
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• pp.294-309
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• 2012

In the age of multi-core and specialized accelerators in high performance computing (HPC) systems, it is critical to understand application characteristics and apply suitable optimizations in order to fully utilize advanced computing system. Often time, the process involves multiple stages of application performance diagnosis and a trial-and-error type of approach for optimization. In this study, a general guideline of performance optimization has been demonstrated with two class-representing applications. The main focuses are on node-level optimization and inter-node scalability improvement. While the number of optimization case studies is somewhat limited in this paper, the result provides insights into the systematic approach in HPC applications performance engineering.

• Journal of Game and Entertainment
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• v.2 no.1
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• pp.71-77
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• 2006

This paper is concerned with the techniques of multitexturing for increasing the image quality of 3D contents in the Internet, where the attributes of objects such as textures are dynamically changed. First we explain the empirical results of implementing the X3D nodes related with the multitexturing in the recent X3D viewers. Next we discuss the directions for developing the next-generation of X3D viewers that satisfy the user requirements and the advanced graphics accelerators.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.272-277
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• 2004

The primary aim of this study is to investigate new semi-abrasive free slurry including acid colloidal silica and hydrogen peroxide for copper chemical-mechanical planarization (CMP). In general, slurry for copper CMP consists of colloidal silica as an abrasive, organic acid as a complex-forming agent, hydrogen peroxide as an oxidizing agent, a film forming agent, a pH control agent and several additives. We developed new semi-abrasive free slurry (SAFS) including below 0.5％ acid colloidal silica. We evaluated additives as stabilizers for hydrogen peroxide as well as accelerators in tantalum nitride CMP process. We also estimated dispersion stability and Zeta potential of the acid colloidal silica with additives. The extent of enhancement in tantalum nitride CMP was verified through anelectrochemical test. This approach may be useful for the application of single and first step copper CMP slurry with one package system.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.428-435
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• 2004

Alkaloid producing species of plants have long been a major component of the medicinal social and magico-religious aspects of human culture. A diverse array of biological activities has been attributed to different alkaloids including numerous members of benzylisoquinoline family of alkaloids. For biotechnological approaches of alkaloid biosynthesis in poppy family, plant regeneration protocol through somatic embryogenesis or shoot organogenesis is a first step. This paper describes the methods and applications of plant regeneration of poppy family.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1792-1797
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• 2020

The shielding characteristics of two concrete blocks, widely used in the building industry in Mexico have been determined. These characteristics include the mass interaction coefficients, the linear attenuation coefficients and the half-value layers. The energy-dispersed X-ray fluorescence shows that the percentage mass content of each atom in the sample, and the atomic volume of the constituent elements of a material, plays an important role in its shielding capabilities. The total linear attenuation coefficients and the half-value layers were analyzed for a set of photon energies related to X-rays for diagnosis and cancer treatment with linear accelerators. Our results show that the concrete blocks have similar photon attenuation coefficients than the Portland concrete and better features than gypsum.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.555-558
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• 2005

The purpose of this study is to evaluate the chemical resistance of polymer powder-modified mortars with special accelerator component. Polymer powder-modified mortars with the accelerator are prepared with various polymer-binder ratios, and tested for flexural and compressive strengths and mass change. Chemicals resistance was tested by dealing with $10\%$ HCl and $5\%\;H_2SO_4$ aqueous solution. As a result, the weight reduction ratio of the mortars decreased with increasing polymer-binder ratio. However, in the viewpoint of strength reduction by chemical attacks, the maximum chemical resistance of the mortars was shown at a polymer-binder ratio of $5\%$.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.559-562
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• 2005

The purpose of this study is to evaluate the durability and bond strength of polymer powder-modified mortars with special accelerator components. The mortars were prepared with various polymer-binder ratios and applied to the concrete substrate as a repair material. Bond strength, flexural and compressive strengths, freeze-thaw resistance and carbonation resistance were measured for the test. As a result, bond strength of the mortars was increased with an increase in the polymer-cement ratio, and freeze-thaw resistance and carbonation resistance were significantly improved with increasing polymer-cement ratio also.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.767-768
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• 2008

Fibre channel based Network-Storage Streaming Accelerator is implemented in this paper. By using Fibre Channel as interface for storage device and sharing storage device among the accelerators, waste of storage space is eliminated. And By using Multi link of Fibre Channels, the load of I/O operations can be distributed over all available links and I/O operations can be conducted even if some links were failed.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.951-954
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• 2002

This paper presents the implementation of hash functions for IPSEC chip. There is an increasing interest in high-speed cryptographic accelerators for IPSec applications such as VPNs (virtual private networks). Because diverse algorithms are used in Internet, various hash algorithms are required for IPSec chip. Therefore, we implemented SHA-1, HAS-160 and MD5 in one chip. These hash algorithms are designed to reduce the number of gates. SHA-1 module is combined with HAS-160 module. As the result, the required logic elements are reduced by 27%. These hash algorithms have been implemented using Altera's EP20K1000EBC652-3 with PCI bus interface.

• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1691-1698
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• 2001

In recent years, significant progress has been made in modeling turbulence behavior in plasma and its effect on transport. It has also been made in diagnostics for turbulence measurement; however, there is still a large gap between theoretical model and experimental measurements. Visualization of turbulence can improve the connection to theory and validation of the theoretical model. One method to visualize the flow structures in plasma is a laser Schlieren imaging technique. We have recently applied this technique and investigated the characteristics of a highly underexpanded pulsed plasma jet originating from an electrothermal capillary source. Measurements include temporally resolved laser Schlieren imaging of a precursor blast wave. Analysis on the trajectory of the precursor blast wave shows that it does not follow the scaling expected for a strong shock resulting from the instantaneous deposition of energy at a point. However, the shock velocity does scale as the square root of the deposited energy, in accordance with the point deposition approximation.