• ETRI Journal
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• v.29 no.5
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• pp.673-675
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• 2007

We present the design and fabrication of a 60 GHz medium power amplifier monolithic microwave integrated circuit with excellent gain-flatness for a 60 GHz radio-over-fiber system. The circuit has a 4-stage structure using microstrip coupled lines instead of metal-insulator-metal capacitors for unconditional stability of the amplifier and yield enhancement. The gains of each stage of the amplifier are modified to provide broadband characteristics of input/output matching for the first and fourth stages and to achieve higher gains for the second and third stages to improve the gain-flatness of the amplifier for wideband.

• Speech Sciences
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• v.14 no.2
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• pp.105-114
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• 2007

The performance of speaker identifier is severely degraded in noisy environments. A study suggested the concept of observation membership for enhancing performances of speaker identifier with noisy speech [1]. The method scaled observation probabilities of input speech by observation identification values decided by SNR. In the paper [1], the authors suggested heuristic parameter values for membership function. In this paper we attempt to apply particle swarm optimization (PSO) for obtaining the optimal parameters for speaker identification in noisy environments. With the speaker identification experiments using the ETRI database we prove that the optimization approach can yield better performance than using only the original membership function.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.119-121
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• 2004

A new and efficient synthesis of the novel bioactive bis(benzopyrano) fused dihydropyridines is described. The conventionally developed route is a two step multicomponent condensation reaction. This is latter modified by a one pot microwave (MW) assisted reaction using inorganic solid support via the arylidene derivative intermediate. With this environmentally benign approach, the reaction time is brought down from hours to minutes along with a yield enhancement. Furthermore, the role of different solid supports is studied and it is concluded that the acidic alumina is the best solid support for the present investigation.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.749-754
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• 2009

The polysaccharide (BB-pol) extracted from Bifidobacterium bifidum BGN4 showed growth inhibitory effects on several colon cancer cell lines such as HT-29 and HCT-116. To increase the yield of polysaccharide, B. bifidum BGN4 was cultured in various culture media with different compositions. When B. bifidum BGN4 was cultured in modified MRS broth containing phytic acid, the cells showed increased branch formation and enlarged morphology. The content of total carbohydrate and the ability of adhesion to intestinal epithelial cells were also increased by phytic acid. The polysaccharide obtained from the cells grown in the presence of phytic acid inhibited the proliferation of cancer cell lines such as HT-29 and MCF-7 cells but not normal colon cell line, FHC. Taken together, Bifidobacterium grown in the presence of phytic acid may confer enhanced beneficial function for the host.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.709-711
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• 2000

Oxidizing metal complex mediates the electrochemical oxidation of guanine nucleotides. This catalysis results in an enhancement in cyclic voltammograms that yield the rate constant for the oxidation of guanine by the metal complex via digital simulation. The rate constant of oxidation of guanine by Ru(bpy)3(3+) is 6.4 x 10(5)M(-1)s(-l). The rate constant and the enhanced current depend on the number of phosphate groups on the sugar of nucleotidc. Also the modified guanine bases show different oxidation rate constants following the trend guanine-5'- monophosphatc (GMP) > 8-bromo-guanine-5'-monophosphate (8-Br-GMP) > xanthosine -5'-monophosphate (XMP) > inosinc-5'-monophosphate (IMP). The guanine bases derivatized differently are all distinguishable from one another, providing a basis for studying electrochemistry of DNA and RNA and developing electrochemical biosensors.

• Electronics and Telecommunications Trends
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• v.33 no.6
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• pp.50-57
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• 2018

As devices have evolved, traditional flip chip bonding and recently commercialized thermocompression bonding techniques have been limited. Laser-assisted bonding is attracting attention as a technology that satisfies both the requirements of mass production and the yield enhancement of advanced packaging interconnections, which are weak points of these bonding technologies. The laser-assisted bonding technique can be applied not only to a two-dimensional bonding but also to a three-dimensional stacked structure, and can be applied to various types of device bonding such as electronic devices; display devices, e.g., LEDs; and sensors.

• Journal of Electrical Engineering and information Science
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• v.1 no.1
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• pp.118-128
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• 1996

In safety critical hard real-time systems, a timing fault may yield catastrophic results. In order to eliminate the timing faults from the fast responsive real-time control systems, it is necessary to schedule a code based on high precision timing analysis. Further, the schedulability enhancement by having multiple processors is of wide spread interest. However, although an instruction level parallel processing is quite effective to improve the schedulability of such a system, none of the real-time applications employ instruction level parallel scheduling techniques because most of the real-time scheduling models have not been designed for fine-grain execution. In this paper, we present a timing constraint model specifying high precision timing constraints, and a practical approach for constructing static schedules for a VLIW execution model. The new model and analysis can guarantee timing accuracy to within a single machine clock cycle.

• KSBB Journal
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• v.19 no.2
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• pp.113-117
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• 2004

The effect of ultrasonification on immuno-stimulatory activities of the extracts from Ephedra sinica Stapf and Rubus coreanus Miq. was observed by the growth of human immune cells. The extraction yields from water extracts and water extract with ultrasonification at 40$^{\circ}C$, 60$^{\circ}C$ and 100$^{\circ}C$ were compared. The highest yield was observed enhancement ratio 2.34% in the extract at 40$^{\circ}C$ with ultrasonification. The growth of human T-cell was increased up to 13.8${\times}$10$^4$ viable cells/$m\ell$ in adding 1.0 g/L of the ultrasonification extracts. The treated extracts increased the specific secretion of TNF-${\alpha}$ up to 10.5${\times}$10$\^$-4/ pg/cell. It was suggested that of the extracts on water the extraction yield with ultrasonification compared improved the extraction with ultrasonification of low than.

• Korean Journal of Acupuncture
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• v.30 no.2
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• pp.122-130
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• 2013

Objectives : The fact that Primo vessel as a new circulatory system exists in the lymphatic vessels of the rabbits which were treated with sound wave vibration therapy is confirmed with the anatomy of rabbit. Isolated Primo vessel is investigated, particularly focused on morphological features. Methods : Before the anatomy, a rabbit in a cage box was laid on the sound wave vibrating apparatus and then is applied by various frequencies and intensities for 30 min with music that a rabbit likes. Results : Isolation and observation of Primo vessel was easier when the lymphatic circular system was applied at a certain frequency and intensity of 7 Hz and 50. The probability of observation for Primo vessel enhanced to 90%. Conclusions : The sound wave therapy by a vibration apparatus is considered necessary as major process to facilitate the reproducible isolation and observation of Primo vessel.

• Korean Journal of Materials Research
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• v.22 no.6
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• pp.303-308
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• 2012

This study evaluated the enhancement of microstructural and mechanical properties of a cross rolled Ni-10Cr alloy, comparing with conventionally rolled material. Cold rolling was carried out to 90% thickness reduction and the specimens were subsequently annealed at $700^{\circ}C$ for 30 min to obtain a fully recrystallized microstructure. Cross roll rolling was carried out at a tilted roll mill condition of $5^{\circ}$ from the transverse direction in the RD-TD plane. In order to observe the deformed microstructures of the cold rolled materials, transmission electron microscopy was employed. For annealed materials after rolling, in order to investigate the grain boundary characteristic distributions, an electron back-scattering diffraction technique was applied. Application of cold rolling to the Ni-10Cr alloy contributed to notable grain refinement, and consequently the average grain size was refined from 135 ${\mu}m$ in the initial material to 9.4 and 4.2 ${\mu}m$ in conventionally rolled and cross rolled materials, respectively, thus showing more significantly refined grains in the cross rolled material. This refined grain size led to enhanced mechanical properties such as yield and tensile strengths, with slightly higher values in the cross rolled material. Furthermore, the <111>//ND texture in the CRR material was better developed compared to that of the CR material, which contributed to enhanced mechanical properties and formability.