• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.12
• /
• pp.53-60
• /
• 2005

This work proposes a 10b 100 MS/s $1.4\;mm^2$ CMOS ADC for low-power multimedia applications. The proposed two-step pipeline ADC minimizes chip area and power dissipation at the target resolution and sampling rate. The wide-band SHA employs a gate-bootstrapping circuit to handle both single-ended and differential inputs with 1.2 Vp-p at 10b accuracy while the second-stage flash ADC employs open-loop offset sampling techniques to achieve 6b resolution. A 3-D fully symmetrical layout reduces the capacitor and device mismatch of the first-stage MDAC. The low-noise references are integrated on chip with optional off-chip voltage references. The prototype 10b ADC implemented in a 0.18 um CMOS shows the maximum measured DNL and INL of 0.59 LSB and 0.77 LSB, respectively. The ADC demonstrates the SNDR of 54 dB, the SFDR of 62 dB, and the power dissipation of 56 mW at 100 MS/s.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.26 no.12B
• /
• pp.1747-1753
• /
• 2001

This paper describe the design and fabrication of a SMD type Wilkinson power divider for PCS basestation. It has been designed for commercial power amplifier system by HP-ADS and fabricated with the size 0.56 $\times$ 0.35 inches. As a result, the power divider was well-operated in the frequency ranges of 1.75 ∼ 1.98GHz for the application of PCS system. The power divider reveals insertion loss 0.2dB, isolation -19.8dB, amplitude balance 0.02dB, phase balance 0.5o, input and output impedance matching -20.6dB respectively.

• 한국초전도학회:학술대회논문집
• /
• 2008.08a
• /
• pp.56-56
• /
• 2008

• Kyungpook Mathematical Journal
• /
• v.56 no.2
• /
• pp.507-516
• /
• 2016

In this paper, we introduce an explicit formula for the solutions and discuss the global behavior of solutions of the difference equation $$x_{n+1}={\frac{ax_{n-3}}{b-cx_{n-1}x_{n-3}}}$$, $n=0,1,{\ldots}$ where a, b, c are positive real numbers and the initial conditions $x_{-3}$, $x_{-2}$, $x_{-1}$, $x_0$ are real numbers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.10 no.5
• /
• pp.757-765
• /
• 1999

In this paper, L-Type aperture coupled circular polarization patch antenna for mobile communication(IMT-2000, 1.9375 GHz), which is capable of being mounted in mobile unit, was designed and fabricated. This antenna is expanded to the $2\times2$ circular polarization array antenna for satellite mobile communications which are using the L-band frequency. The results are as followings : Returnloss 18.56 dB, beamwidth $60^{\circ}$, gain 7 dBd, axial ratio 0.9 dB in the case of single element and returnloss 28.43 dB, beamwidth $38^{\circ}$, gain 9.8dBd, axial ratio 1.5 dB in the case of $2\times2$ array, respectively.

• Korean Journal of Microbiology
• /
• v.20 no.4
• /
• pp.183-188
• /
• 1982

The neurotoxin of Clostridium botulinum type B was purified from a liquid culture. The purification steps consist of ammonium sulfate precipitation of whole culture, treatment of Polymin P(0.15%, v/v), gel filtration on Sephadex G-100 at pH5.6 and DEAE-Sephadex charomatography at pH8.0. The procedure recovered 17% of the toxin assayed in the starting culture. The toxin was homogeneous by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis and had a molecular weight of 163, 000. Subunits of 106, 000 and 56, 000 molecular weight were found when purified toxin was treated with a disulfide-reducing agent and electro phoresed on SDS-polyacrylamide gels.

• The Bulletin of The Korean Astronomical Society
• /
• v.41 no.2
• /
• pp.56.1-56.1
• /
• 2016

A low-mass star-forming region, L1251B, is an excellent example of a small and nearby group of protostellar objects. L1251B has been mapped spectroscopically with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. IRS has provided mid-IR emission lines (e.g., [Fe II], [Ne II], and ro-vibrational H2) and absorption features of CO2 and H2O ice in studying the physical state of the ionized gas and the material residing in the circumstellar environments. We will present the distribution of outflows and ice components in L1251B.

• Bulletin of the Korean Chemical Society
• /
• v.17 no.1
• /
• pp.56-60
• /
• 1996

The pressure saturation effect on the phosphorescence decay rates of the $^3B_1$ State of $SO_2$ has been reinvestigated by the laser induced phosphorescence method in pure $SO_2$. We have attempted to fit the pressure dependence of the phosphorescence decay rates using the radiationless transition model by introducing different coupling constants for each vibrational level ofthe 3B1 state. The experimental decay rates can be fitted well, when the coupling constants for the (0,0,0), (0,1,0) and (0,2,0) levels of the $^3B_1$ state are $7.2\;{\times}\;10^{-4}$, $2.2\;{\times}\;10^{-3}$ and $5.9\;{\times}\;10^{-3}\;cm^{-1}$, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.38 no.2
• /
• pp.119-128
• /
• 2002

This study investigates dorsal aspect target strength with fish size, tilt angle and frequency characteristics for the schlegel's black rockfish(Sebastes achlegeli) and the red seabream (Pagrus major). This study was carried out on free swimming fish in a cage in order to obtain acoustic data of the biomass estimation using the scientific echo sounder. The results obtained from this study are summarized as follows; 1 The coefficients of the schlegel's black rockfish and the red seabream using maximum TS with fish length were expressed -63.7dB and -62.6dB at a frequency of 38kHz, -64.4dB and -65.4dB at 120kHz, and -62.4dB and -65.0dB at 200kHz, respectively. 2. The coefficients of the schlegel\`s black rockfish and the red seabream using averaged TS with fish length were expressed -68.4dB and -67.9dB at a frequency of 38kHz, -73.4dB and -72.7dB at 120kHz, and -70.BdE and -73.4dB at 2001Hs, respectively. 3. The coefficients of the schlegel's black rockfish and the red seabream using maximum TS with body weight were expressed -52.0dB and -50.9dB at a frequency of 38kHz, -52.7dB and -53.7dB at 120kHz, and -50.7dB and -53.3dB at 200kHz, respectively. 4. The coefficients of the schlegel's black rockfish and the red seabream using averaged TS with body weight were expressed -56.7dB and -56.2dB at a frequency of 38kHz, -61.7dB and -61.0dB at 120kHz, and -59.ldE and -61.6dB at 200kHz, respectively. 5. Varying the tiIt angle of the two red seabream from -26$^{\circ}$to +25$^{\circ}$, the variation width of target strength expressed smaller at a frequency of 38kHz than at 120kHz and expressed about 3~6dB higher head up than head down at 120kHz.

• Monthly Korean Chicken
• /
• v.56 no.50 s.116
• /
• pp.77-81
• /
• 2005