• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1992.05a
• /
• pp.91-96
• /
• 1992

The nonvolatile SNOSFET EEPROM memory devices with the channel width and iength of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$], 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$] and 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$] were fabricated by using the actual CMOS 1 [Mbit] process technology. The charateristics of I$\_$D/-V$\_$D/, I$\_$D/-V$\_$G/ were investigated and compared with the channel width and length. From the result of measuring the I$\_$D/-V$\_$D/ charges into the nitride layer by applying the gate voltage, these devices ere found to have a low conductance state with little drain current and a high conductance state with much drain current. It was shown that the devices of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$] represented the long channel characteristics and the devices of 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$] and 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$] represented the short channel characteristics. In the characteristics of I$\_$D/-V$\_$D/, the critical threshold voltages of the devices were V$\_$w/ = +34[V] at t$\_$w/ = 50[sec] in the low conductance state, and the memory window sizes wee 6.3[V], 7.4[V] and 3.4[V] at the channel width and length of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$], 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$], 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$], respectively. The positive logic conductive characteristics are suitable to the logic circuit designing.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.25 no.1
• /
• pp.12-17
• /
• 1989

A field experiment was carried out of confirm the effect of underwater sound on the luring of fish school of chub mackerel in the coast of Idousyo Island. Underwater sound that was made use of luring of fish school was pure sound and interval pure sound which the frequencies of the sound were 150Hz and 200Hz, respectively. The results of the observation of hooking and recording paper of fish finder indicate that the effect of emitting sound at 20m in the depth of water was remarkable for the luring of fish school of chub mackerel. The vertical pure sound pressure level at 150Hz and 200Hz of the water layer that was lured the fish school of chub mackerel were 140.1dB and 146.dB at 30m, 121.0dB and 126.6dB at 70m and 141.9dB and 120.5dB at 120m in the depth of water, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.11 no.6
• /
• pp.893-899
• /
• 2000

A 900 MHz low-noise amplifier(LNA) with a measured noise figure of 4.8 dB and an associated gain of 13.2 dB was fabricated in a 0.65 $\mu$m CMOS. The inductive source architecture of offers the possibility of achieving the best noise performance. At 900 MHz, the fabricated LNA dissipates 39 mW from a single 3 V power supply including the bias circuitry and provides -26dB input return loss, -17 dB output return loss, and an input 1-dB compression level of -12 dBm.

• Bulletin of the Korean Chemical Society
• /
• v.4 no.2
• /
• pp.72-76
• /
• 1983

Cephaloglycin was synthesized directly from D-${\alpha}$ -phenylglycine methyl ester and 7-aminocephalosporanic acid using whole cell enzyme of Xanthomonas citri (IFO 3835). Some optimal conditions for cephaloglycin synthesis were investigated, and yield improvements for its production by several methods were attempted. Using the whole cell enzyme system, the reaction kinetic model for cephaloglycin synthesis is proposed, and the kinetic constants for D-${\alpha}$ -phenylglycine methyl ester hydrolysis, cephaloglycin synthesis, and cephaloglycin hydrolysis were determined. The $K_m$ values of D-${\alpha}$-phenylglycine methyl ester, 7-aminocephalosporanic acid, and cephaloglycin were 11 mM, 24 mM, and 167 mM, and $K_i$ value of D-${\alpha}$-phenylglycine was 15 mM, respectively. The pattern of product inhibition was found to be competitive one.

• Journal of Wetlands Research
• /
• v.14 no.2
• /
• pp.211-221
• /
• 2012

The ascidian Styela clava has been one of the favorite seafood in Korea. Suspended culture of Styela clava was initiated in 2001 and the annual production reached 15,084 M/T, but declined to 2,655 M/T in 2011. In order to solve this problem, it is necessary to estimate the material balance according to the farm-environment. Vertical particulate fluxes and release fluxes were estimated at 2 stations, an ascidian farm (AF) and a non-cultivated area (control) in Jindong Bay. An in-situ benthic chamber(BelcI) was used in summer and winter season. The sedimentation fluxes of organic carbon were 72 mmol C $m^{-2}\;d^{-1}$, 93 mmol C $m^{-2}\;d^{-1}$, 34 mmol C $m^{-2}\;d^{-1}$ in Jul. AF, Feb. AF, Feb. control. The organic carbon oxidation rates were 13 mmol C $m^{-2}\;d^{-1}$, 81 mmol C $m^{-2}\;d^{-1}$, 31 mmol C $m^{-2}\;d^{-1}$, in each. The release fluxes of nutrients followed the general pattern, well. Consequently, the ratio of the organic carbon burial fluxes were 20:4:1, in each. By the estimation of the carbon circulation, it could be a scientific basis to analyze the reason of production decline for cultivated organism.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.40 no.6
• /
• pp.127-140
• /
• 2003

This paper develops a novel algorithm of computing 2 Dimensional Discrete Cosine Transform (2D-DCT) via Polynomial Transform (PT) converting 2D-DCT to the sum of 1D-DCTs. In computing N${\times}$M size 2D-DCT, the conventional row-column algorithm needs 3/2NMlog$_2$(NM)-2NM＋N＋M additions and 1/2NMlog$_2$(NM) additions and 1/2NMlog$_2$(NM) multiplications, while the proposed algorithm needs 3/2NMlog$_2$M＋NMlog$_2$N-M-N/2＋2 additions and 1/2NMlog$_2$M multiplications The previous polynomial transform needs complex operations because it applies the Euler equation to DCT. Since the suggested algorithm exploits the modular regularity embedded in DCT and directly decomposes 2D DCT into the sum of ID DCTs, the suggested algorithm does not require any complex operations.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.5
• /
• pp.682-687
• /
• 2022

In this paper, the research results on monolithic three-dimensional integrated-circuit (M3DICs) stacked with tunneling field effect transistors (TFETs) are introduced. Unlike metal-oxide-semiconductor field-effect transistors (MOSFETs), TFETs are designed differently from the layout of symmetrical MOSFETs because the source and drain of TFET are asymmetrical. Various monolithic 3D inverter (M3D-INV) structures and layouts are possible due to the asymmetric structure, and among them, a simple inverter structure with the minimum metal layer is proposed. Using the proposed M3D-INV, this M3D logic gates such as NAND and NOR gates by sequentially stacking TFETs are proposed, respectively. The simulation results of voltage transfer characteristics of the proposed M3D logic gates are investigated using mixed-mode simulator of technology computer aided design (TCAD), and the operation of each logic circuit is verified. The cell area for each M3D logic gate is reduced by about 50% compared to one for the two-dimensional planar logic gates.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.18 no.2
• /
• pp.61-67
• /
• 1982

Optical properties of sea water were studied in the southern sea of Korea, based on ten oceanographic stations in July, 1980. Submarine daylight intensity was measured at intervals of 5m depth in the upper 70m layer by using the underwater irradiameter (Kahlsico # 268 WA 360). The mean absorption coefficients of the sea water were shown as 0.102 (0.066~0.137), 0.119 (0.069~0.154), 0.091 (0.054~.0123), and 0.095 (0.056~0.129) for clear, red, green, and blue color respectively. The transparency ranged from 13 to 25 meters (mean 17.1 m). The mean water color in this area was 3.9 (3-5) in Forel scales. The relation between absorption coefficient (k) and transparency (D) was k=1.17/D, k=2.01/D, k=1.52/D, and k=1.60/D for clear, red, green, and blue color respectively. The rates of light penetration for clear, red, green, and blue color in four different depths were computed with reference to the surface light intensity respectively. The mean rates of light penetration in proportion to depths were as follows; clear : 57.3%(5m), 20.82%(15m), 5.16%(30m), 0.94%(50m). red : 52.2%(5m), 15.99%(15m), 2.99%(30m), 0.39%(50m). green : 60.9%(5m), 24.51%(15m), 7.11%(30m), 1.56%(50m). blue : 59.4%(5m), 22.92%(15m), 6.09%(30m), 1.29%(50m).

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.spc
• /
• pp.45-46
• /
• 2009

This study was carried out to identify the changes of EC during desalinization due to flooding in newly reclaimed saline soil. To do this, experimental plots were made of rotary tillage+water exchanging plot, flooding plot and rainfall flooding plot. In rotary tillage+water exchanging plot, drainage, rotary tillage and flooding were conducted at the interval of 7 days. In rotary tillage+water exchanging plot and flooding plot, plots were irrigated at the height of 10 cm. After 38 days desalinization, changes of EC values at top soil (0~20 cm) were as follows. In rotary tillage+water exchanging plot, EC decreased from $21.38dS\;m^{-1}$ to $2.16dS\;m^{-1}$ and in flooding plot, EC decreased from $13.97dS\;m^{-1}$ to $2.22dS\;m^{-1}$. In rotary tillage+water exchanging plot and flooding plot, EC values decreased below the EC criterion ($4.0dS\;m^{-1}$) of saline soil. In rainfall flooding plot, EC values decreased or increased according to amounts of rainfall and rainfall time. After 38 days, EC decreased from $16.7dS\;m^{-1}$ to $12.35dS\;m^{-1}$. In flooding plot, changes of EC due to soil depth were investigated. After 38 days desalinization, changes of EC due to soil depth were as follows. At 0~10 cm depth, EC value decreased from $13.08dS\;m^{-1}$ to $0.74dS\;m^{-1}$ (94.3% of salt was desalinized). At 10~20 cm depth, EC value decreased from $14.80dS\;m^{-1}$ to $3.69dS\;m^{-1}$ (75.2% of salt was desalinized). At 20~30 cm depth, soil was desalinized slowly compared with upper soil, EC value decreased from $13.57dS\;m^{-1}$ to $6.93dS\;m^{-1}$ (48.9% of salt was desalinized).

• Journal of Pharmacopuncture
• /
• v.21 no.1
• /
• pp.18-25
• /
• 2018

Objective: D-galactose (D-gal) is well-known agent to induce aging process. In the present study, we selected crocin, the main constituent of Crocus sativus L. (saffron), against D-gal- induced cytotoxicity in human neuroblastoma SH-SY5Y cells. Methods: Pretreated cells with crocin ($25-500{\mu}M$, 24 h) were exposed to D-gal (25-400 mM, 48 h). The MTT assay was used for determination cell viability. Dichlorofluorescin diacetate assay (DCF-DA) and senescence associated ${\beta}$-galactosidase staining assay (SA-${\beta}$-gal) were used to evaluate the generation of reactive oxygen species and beta-galactosidase as an aging marker, respectively. Also advanced glycation end products (AGEs) expression which is known as the main mechanism of age-related diseases was measured by western blot analysis. Results: The findings of our study showed that treatment of cells with D-gal (25-400 mM) for 48h decreased cell viability concentration dependency. Reactive oxygen species (ROS) levels which are known as main factors in age-related diseases increased from $100{\pm}8%$ in control group to $132{\pm}22%$ in D-gal (200 mM) treated cells for 48h. The cytotoxic effects of D-gal decreased with 24h crocin pretreatment of cells. The cell viability at concentrations of $100{\mu}M$, $200{\mu}M$ and $500{\mu}M$ increased and ROS production decreased at concentrations of 200 and $500{\mu}M$ to $111.5{\pm}6%$ and $108{\pm}5%$, respectively. Also lysosomal biomarker of aging and carboxymethyl lysine (CML) expression as an AGE protein, significantly increased in D-gal 200 mM group after 48h incubation compare to control group. Pre-treatment of SHSY-5Y cells with crocin ($500{\mu}M$) before adding D-gal significantly reduced aging marker and CML formation. Conclusion: Treatment of SH-SY5Y cells with crocin before adding of D-gal restored aging effects of D-gal concentration dependency. These findings indicate that crocin has potent anti- aging effects through inhibition of AGEs and ROS production.