• Journal of Information Processing Systems
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• 제9권2호
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• pp.205-216
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• 2013

In this paper, we analyze a technique for building a high-availability (HA) cluster system. We propose what we have termed the 'Selective Replication Manager (SRM),' which improves the throughput performance and reduces the latency of disk devices by means of a Distributed Replicated Block Device (DRBD), which is integrated in the recent Linux Kernel (version 2.6.33 or higher) and that still provides HA and failover capabilities. The proposed technique can be applied to any disk replication and database system with little customization and with a reasonably low performance overhead. We demonstrate that this approach using SRM increases the disk replication speed and reduces latency by 17% and 7%, respectively, as compared to the existing DRBD solution. This approach represents a good effort to increase HA with a minimum amount of risk and cost in terms of commodity hardware.

• 소성∙가공
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• 제22권1호
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• pp.36-41
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• 2013

The present study examines the micro-pattern replication on a plastic film using ultrasonic imprinting. Ultrasonic imprinting uses ultrasonic waves to generate repetitive microscale deformation in the polymer film. The resulting deformation heat on the surface of the film causes the surface region to soften sufficiently so that a replication of the micro-pattern can be obtained. To successfully replicate the micro-pattern on a large area of polymer film, a high replication ratio is needed as well as good uniformity over the entire region. In this study, a horn design is investigated by finite element analysis and is optimized through a response surface analysis. In the ultrasonic imprinting experiments, the response surface method was also used to determine the optimal processing conditions for better replication characteristics.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1537-1541
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• 2007

We injection molded a wedge type of plate with micro prizm patterns on its surface and investigated the fidelity of replication of the micro pattern depending on the process parameter such as mold temperature, melt temperature, injection rate or packing pressure. The size of the size of the $90^{\circ}$ prizm pattern is $50{\mu}m$ and the size of the plate is about 300㎜${\times}$200㎜. The thicknesses are 2.6㎜. and 0.7mm at each edge of the wedge type of plate. The fidelity of the replication turned out quite different according to the process parameters and location of the patterns on the plate. We measured the cavity pressure and temperature in real-time during the molding to analyze the effect of the local melt pressure and temperature on the micro pattern replication.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1078-1082
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• 2003

A feasibility study for the fabrication of master replication with nanostructures by Nanoimprint Lithography (NIL) was investigated for application of polymer Photonic Bandgap (PBG) devices used in photonic IC. Large area gratings of $9{\times}15(mm^2)$ with p = 400 nm was successfully embossed on PMMA on silicon wafer and the embossing parameters (temperature, pressure, time) were established. A precise control of $O_2$ plasma Reactive Ion Etching (RIE) process time allowed window opening over the whole area despite the presence of wafer bending. Master replication with aspect ratio 1 was successfully fabricated, but master replication with aspect ratio 3 needs to optimize parameters. All replications were done in a NIL process.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1332-1336
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• 2003

An experimental method is presented to maximize the replication quality of UV-molded micro-optical components. It is important to maximize the replication quality, because one can obtain the replicated micro-optical components with desired properties by accurate control of the shape. In the present study, a simple technique to avoid micro-air bubbles was first suggested. The effects of the UV-curing dose and the compression pressure on the replication quality of UV-molded structure were examined experimentally. Finally, as a practical application of the process design method, microlens arrays with diameters between 8 ${\mu}m$ and 96 ${\mu}m$ were fabricated by the present method, and the replication quality and the optical properties of the replicated microlens were measured and analyzed.

• 한국생산제조학회지
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• 제25권3호
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• pp.224-229
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• 2016

Recently, polymeric micro-fluidic biochips with numerous micro patterns on the surface were fabricated by injection molding for realizing low-cost mass production of devices. To evaluate the effects of process parameters on large-scale micro-structure replication, a $50{\times}50mm^2$ tool insert with surface structures having a patterns of trapezoidal shapes (height: $30{\mu}m$) was employed. During injection molding, PMMA was used; packing phase parameters and mold temperature were investigated. The replicated surface textures were quantitatively characterized by confocal laser microscopy with 10-nm resolution. The degree of replication at low mold temperatures was found to be higher than that at high mold temperature at the beginning of the packing stage. Thereafter, the degree of replication increased to a greater extent at higher mold temperatures; application of higher mold temperatures improved the degree of replication.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.79-82
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• 2005

Fresnel lens has number of applications in the optical systems because of its advantages. It is nearly flat lens that has small weight. It is conventionally used in lighthouse beacons, condensing unit of overhead projector and etc. Recently, demands of small size optical systems such as display units, information storage systems, optical detecting units had increased. Conventional manufacturing process of high quality Fresnel lens is direct machining. But it is not suitable for mass production because of high cost and long cycle time. Replication process is more suitable for mass production. But the Fresnel lens has number of sharp blade shape prism. In the replication process, this blade shape causes defects that can affect optical efficiency. In this study, replication process of blade shape pattern that has maximum height of $280{\mu}m$, aspect ratio 1.4 for Fresnel lens application.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.92-92
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• 1993

Point mutations in a highly conserved central region of the HIV-1 integrase protein were analyzed for their effects on viral replication and virion morphogenesis. Conservative amino acid replacements of two amino acid residues invariant un retroviral integrases, D116 and E152 of HIV-1, as well as the highly conserved amino acid S147, completely blocked viral replication in two CD4$\^$＋/ human T cell lines. Mutation of four other highly conserved amino acids in the region had no detectable effect on viral replication, while Mutations at two positions, N117 and Y143, resulted in viruses with a delayed replication phenotype. Characteristic and reproducible defects id virion core structure were observed by electron microscopic analysis of sore of the replication defective integrase point mutants, indicating that mutant integrase proteins can interfere with the process of virion core maturation.

• 미생물학회지
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• 제26권3호
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• pp.162-166
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• 1988

Bacteriophage M13 DNAs carrying the wild type or base substituted SV40 DNA replication origins were used for replication assay. In vivo and in vitro assay with African green monkey cell line COS-1 showed that the replication of M13-SV40 recombinant DNAs was restricted like a pBR322 SV40 recombinant DNA(Lusky and Botchan, 1981). Furthermore, recombinant phage DNAs isolated from the transfected siminan cells subsequently show a reduced ability to retransform E. coli. But pATSV-W(Kim et al., 1988) was replicated in COS-1 cells normally. We think that a poison sequence may exist on bacteriophage M13 DNA like pBR322.

• BMB Reports
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• 제41권11호
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• pp.778-783
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• 2008

Turnip yellow mosaic virus (TYMV) RNA has two hairpins in its 5' untranslated region (5'-UTR). To investigate the role of the hairpins in replication of TYMV, mutants lacking one or both of the two hairpins were constructed. The TYMV constructs were introduced into Chinese cabbage by an Agrobacterium-mediated T-DNA transfer method, called agroinfiltration. Analysis of total RNA from agroinfiltrated leaves showed that replication of the mutant TYMV RNA lacking both hairpins was about 1/100 of wild type. This mutant was also impaired in systemic spread. Deletion analysis of each hairpin revealed that both hairpins were needed for maximal replication. The deletion analysis along with sequence modification of the hairpin structure indicates that the second hairpin plays a role in efficient long-distance systemic movement of TYMV.