• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4331-4338
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• 2014

$N^1$-(2, 5-dimethoxyphenyl)-$N^8$-hydroxyoctanediamide (N25) is a novel SAHA cap derivative of HDACi, with a patent (No. CN 103159646). This invention is a hydroxamic acid compound with a structural formula of $RNHCO(CH_2)6CONHOH$ (wherein R=2, 5dimethoxyaniline), a pharmaceutically acceptable salt which is soluble. In the present study, we investigated the effects of N25 with regard to drug distribution and molecular docking, and anti-proliferation, apoptosis, cell cycling, and $LD_{50}$. First, we designed a molecular approach for modeling selected SAHA derivatives based on available structural information regarding human HDAC8 in complex with SAHA (PDB code 1T69). N25 was found to be stabilized by direct interaction with the HDAC8. Anti-proliferative activity was observed in human glioma U251, U87, T98G cells and human lung cancer H460, A549, H1299 cells at moderate concentrations ($0.5-30{\mu}M$). Compared with SAHA, N25 displayed an increased antitumor activity in U251 and H460 cells. We further analyzed cell death mechanisms activated by N25 in U251 and H460 cells. N25 significantly increased acetylation of Histone 3 and inhibited HDAC4. On RT-PCR analysis, N25 increased the mRNA levels of p21, however, decreased the levels of p53. These resulted in promotion of apoptosis, inducing G0/G1 arrest in U251 cells and G2/M arrest in H460 cells in a time-dependent and dose-dependent manner. In addition, N25 was able to distribute to brain tissue through the blood-brain barrier of mice ($LD_{50}$: 240.840mg/kg). In conclusion, our findings demonstrate that N25 will provide an invaluable tool to investigate the molecular mechanism with potential chemotherapeutic value in several malignancies, especially human glioma.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.180-181
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• 2001

이 논문은 채널당 1Gbps로 동작하는 10채널 광 수신기를 0.25$mu extrm{m}$ CMOS공정을 이용하여 설계한 것이다. 광 수신기는 크게 2부분으로 나눠지는데 첫 번째 부분은 입력된 전류 신호를 전압 신호로 변환시켜주는 역할을 하는 트랜스임피던스 전치증폭기이고, 다음 부분은 원하는 디지털 레벨로 풀스윙 할 수 있도록 하는 후치증폭기이다. 전치증폭기의 출력 전압은 스윙폭에 무관하게 그 다음 단에서 적당한 디지털 레벨 데이터로 변환되어야한다. (중략)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12B
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• pp.1695-1702
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• 2001

This paper describes a design of CMOS infrared (IR) wireless data link IC which can be used in IrDA(Infrared Data Association) application from 4 Mb/s to 100 Mb/s The implemented chip consists of variable gain transimpedance amplifier which has a gain range from 60 dB to 100 dB, AGC (automatic gain control) circuits, AOC(automatic offset control) loop, 4 PPM (pulse position modulation) modulator/demodulator and DLL(delay locked loops). This infrared optical link If was implemented using commercial 0.25 um 1-poly 5-metal CMOS process. The chip consumes 25 mW at 100 Mb/s with 2.5 V supply voltage excluding buffer amplifier. The die area of prototype IC is 1.5 mm $\times$ 1 mm.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.4
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• pp.401-410
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• 2014

This paper presents a high-efficiency concurrent dual-band Class-E power amplifier(PA) that is based on a multi-harmonic matching network(MHMN). The proposed MHMN controls the impedance at 1.3 GHz, 2.1 GHz, and their second and third harmonics, respectively, by using transmission lines only rather than switches or lumped components. The dual-band Class-E PA is implemented using Avago ATF-50189 GaAs p-HEMT. The PA exhibits a measured output power of 27.1 dBm and 25.7 dBm, a power gain of 6.1 dB and 4.7 dB, and a drain efficiency of 71.2 % and 60.1 % at 1.3 GHz and 2.1 GHz, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.48-59
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• 2021

In this study, experiments were conducted to investigate the compressive·flexural performances of single fiber-reinforced mortar (FRM) using only steel fiber or carbon fiber which has different material properties as well as hybrid FRM using a mixture of steel and carbon fibers. The mortar specimens incorporated steel and carbon fibers in the mix proportions of 1+0%, 0.75+0.25%, 0.5+0.5%, 0.25+0.75% and 0+1% by volume at a total volume fraction of 1.0%. Their mechanical performance was compared and examined with a plain mortar without fiber at 28 days of age. The experiments of mortar showed that the hybrid FRM using a mixture of 0.75% steel fibers + 0.25% carbon fibers had the highest compressive and flexural strength, confirming by thus the synergistic reinforcing effect of the hybrid FRM. On the contrast, in the case of hybrid FRM using a mixture of 0.5% steel fibers + 0.5% carbon fibers witnessed the highest flexural toughness, suggesting as a result the optimal fiber mixing ratio of hybrid FRM to improve the strength and flexural toughness at the same time. Moreover, the fracture surface was observed through a scanning electron microscope (SEM) for image analysis of the FRM specimen. These results were of great help for images analysis of hybrid reinforcing fibers in cement matrix.

• Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.243-249
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• 2022

Bacillus SW1-1 is a probiotic isolated from shrimp intestines. We investigated the effects of Bacillus SW1-1 coated diets on the growth, feed utilization, innate immunity, hematological parameters and resistance to Edwardsiella tarda in olive flounder (Paralichthys olivaceus). A commercial diet was used as the control (AP0) and two other diets were prepared by coating 0.25% (AP25) or 0.50% (AP50) probiotic powder which contains 1.0 × 10⁷ CFU/g Bacillus SW1-1. Four replicate groups of olive flounder (153 ± 2 g) were fed one of the diets for 12 weeks. Growth performance and feed utilization of the fish were not significantly affected by the dietary Bacillus SW1-1. After the challenge with E. tarda, AP50 group showed significantly higher survival than AP0 and AP25 groups. Innate immunity and anti-oxidant capacity of the fish were not significantly affected after the feeding trial. However, after the E. tarda challenge, the innate immune parameters (immunoglobulin, lysozyme and anti-protease) were significantly improved in fish fed AP25 and AP50 diets compared to those in fish fed AP0 diet. After the challenge test, significantly lower glucose level was observed in AP50 group compared to AP0 group. These results indicate that dietary supplementation of Bacillus SW1-1 could increase the disease resistance of olive flounder against E. tarda infection. The optimum coating levels of Bacillus SW1-1 needs to be further elucidated.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.165-168
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• 2002

As the demand for higher data-rate chip-to-chip communication such as memory-to-controller, processor-to-processor increases, low cost high-speed serial links\ulcorner become more attractive. This paper describes a 0.25-fm CMOS 1.6Gbps/pin 4-level transceiver using Stub Series Terminated Logic for high Bandwidth. For multi-gigabit/second application, the data rate is limited by Inter-Symbol Interference (ISI) caused by channel low pass effects, process-limited on-chip clock frequency, and serial link distance. The proposed transceiver uses multi-level signaling (4-level Pulse Amplitude Modulation) using push-pull type, double data rate and flash sampling. To reduce Process-Voltage-Temperature Variation and ISI including data dependency skew, the proposed high-speed calibration circuits with voltage swing controller, data linearity controller and slew rate controller maintains desirable output waveform and makes less sensitive output. In order to detect successfully the transmitted 1.6Gbps/pin 4-level data, the receiver is designed as simultaneous type with a kick - back noise-isolated reference voltage line structure and a 3-stage Gate-Isolated sense amplifier. The transceiver, which was fabricated using a 0.25 fm CMOS process, performs data rate of 1.6 ~ 2.0 Gbps/pin with a 400MHB internal clock, Stub Series Terminated Logic ever in 2.25 ~ 2.75V supply voltage. and occupied 500 * 6001m of area.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.4
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• pp.57-63
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• 2006

For chip-stack package applications, Cu filling characteristics into trench vias of $75{\sim}10\;{\mu}m$ width and 3 mm length were investigated with variations of electroplating current density and current mode. At $1.25mA/cm^{2}$ of DC mode, Cu filling ratio higher than 95% was obtained for trench vias of $75{\sim}35{\mu}m$ width. When electroplated at DC $2.5mA/cm^{2}$, Cu filling ratios became inferior to those processed at DC $1.25mA/cm^{2}$. Pulse current mode exhibited Cu filling characteristics superior to DC current mode.

• Journal of IKEEE
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• v.25 no.1
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• pp.25-31
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• 2021

The conventional credit card number recognition system generally needs a card to be placed in a designated location before its processing, which is not an ideal user experience especially for people with visual impairment. To improve the user experience, this paper proposes a novel algorithm that can automatically detect the location of a credit card number based on the fact that a group of sixteen digits has a fixed aspect ratio. The proposed algorithm first performs morphological operations to obtain multiple candidates of the credit card number with >4:1 aspect ratio, then recognizes the card number by testing each candidate via OCR and BIN matching techniques. Implemented with OpenCV and Firebase ML, the proposed scheme achieves 77.75% accuracy in the credit card number recognition task.

• The Korean Journal of Ecology
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• v.15 no.3
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• pp.257-265
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• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.