• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1329-1336
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• 1998

A twt -step carbothermal reduction scheme has been employed for the synthesis of SiC whiskers in an Ar or a H2 atmosphere via vapor-solid two-stage and vapor-liquid-solid growth mechanism respectively. It has been shown that the whisker growth proceed through the following reaction mechanism in an Ar at-mosphere : SiO2(S)+C(s)-SiO(v)+CO(v) SiO(v)3CO(v)=SiC(s)whisker+2CO2(v) 2C(s)+2CO2(v)=4CO(v) the third reaction appears to be the rate-controlling reaction since the overall reaction rates are dominated by the carbon which is participated in this reaction. The whisker growth proceeded through the following reaction mechaism in a H2 atmosphere : SiO2(s)+C(s)=SiO(v)+CO(v) 2C(s)+4H2(v)=2CH4(v) SiO(v)+2CH4(v)=SiC(s)whisker+CO(v)+4H2(v) The first reaction appears to be the rate-controlling reaction since the overall reaction rates are enhanced byincreasing the SiO vapor generation rate.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.7-13
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• 2020

We describes V2X technology, a connectivity-based recognition technology that is attracting attention as a key technology for implementing autonomous driving technology, and autonomous communication modules that implement ADAS technology, a sensor-based recognition technology. It also explains the trends in V2X technology standardization centered on IEEE 802.11p, which is a WAVE technology standard based on Wi-Fi/DSRC. Finally, we will discuss the market growth trend of V2X communication modules in the United States, the leading V2X technology module, and the development of technology development trends of major domestic and international companies that are leading the global technology market related to V2X communication modules. V2X and ADAS technologies will be the biggest influence on automotive purchasing decisions. In recent years, V2I mandates have been promoted beyond V2V, mainly in developed countries such as the United States. The related industry needs to focus on the development of information transmission network technology that can support high frequency high efficiency(transmission rate) and sophisticated positioning accuracy beyond conventional vehicle communication.

• Journal of Sensor Science and Technology
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• v.3 no.3
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• pp.22-27
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• 1994

Design of potentiostat and I-V converter for micro pO2 sensor is described. Also, The operation of the designed circuit, in connection with the eqivalent model of micro pO2 sensor, is simulated. The potentiostat showed low output resistance of $l.1k{\Omega}$ and input voltage range of $-3{\sim}2.5V$. And the I-V converter showed low input resistance of $30{\Omega}$ and good linearity between input and output.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.6 s.360
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• pp.19-27
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• 2007

This paper presents power supply-insensitive Gbps low power LVDS I/O circuits. The proposed LVDS I/O has been designed and simulated using 1.8V, $0.18\;{\mu}m$ TSMC CMOS Process. The LVDS I/O includes transmitter and receiver parts. The transmitter circuits consist of a differential phase splitter and an output stage with the switched capacitor common mode feedback(SC-CMFB). The differential phase splitter generates a pair of differential signals which provides a balanced duty $cycle(50{\pm}2%)$ and phase difference$(180{\pm}0.2^{\circ})$ over a wide supply voltage range. Also, $V_{OD}$ voltage is 250 mV which is the smallest value of the permissible $V_{OD}$ range for low power operation. The output buffer maintains the required $V_{CM}$ within the permissible range$(1.2{\pm}0.1V)$ due to the SC-CMFB. The receiver covers a wide input DC offset $range(0.2{\sim}2.6\;V)$ with 38 mV hysteresis and Produces a rail-to-rail output over a wide supply voltage range. Beside, the designed receiver has 38.9 dB gain at 1 GHz, which is higher than conventional receivers.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.135-143
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• 2012

This paper suggests the optimal blood distribution center algorithm that satisfies the minimum total transportation cost and within the allowable distribution time $T^*$. Zhang and Yang proposes shifting the location of each point that has less than the average distance of two maximum distance points from each point. But they cannot decide the correct facility location because they miscompute the shortest distance. This algorithm computes the shortest distance $l_{ij}$ from one area to another areas. Then we select the $v_i$ area to thecandidate distribution center location such that $_{max}l_{ij}{\leq}L^*$ and the $v_i$ such that $l_{ij}-L^*$ area that locates in ($v_i,v_k$) and ($v_j,v_l$) from $P_{ij}=v_i,v_k,{\cdots},v_l,v_j$ path and satisfies the $_{max}l_{ij}{\leq}L^*$ condition. Finally, we decide the candidate distribution area that has minimum transportation cost to optimal distribution area.

• Journal of Life Science
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• v.22 no.2
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• pp.245-250
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• 2012

The 16S rDNA - RFLP types for six Vibrio species (V. fluvialis, V. proteolyticus, V. vulnificus, V. mimicus) including two core group members, V. alginolyticus and V. parahaemolyticu s, and Grimontia (Vibrio) hollisae were determined using PCR-RFLP analysis. Six tetrameric restriction enzymes (Alu I, Cfo I, Dde I, Hae III, Msp I, and Rsa I) were selected for RFLP analysis. V. alginolyticus, V. parahaemolyticus, and V. proteolyticus showed the same RFLP pattern following digestion with four of the six used restriction enzymes: CfoI, DdeI, MspI, and RsaI. Various restriction enzyme combinations generated digests recognizable as distinct RFLP types for each of the assayed Vibrio species. In particular, AluI single digestion produced species specific band patterns that enabled the differentiation between these Vibrio species. Dendrogram based on restriction patterns showed that two Vibrio core group members, V. alginolyticus and V. parahaemolyticus were closely related having a similarity over 90%. Although the observed RFLP pattern for Grimontia hollisae shared several common bands with other Vibrio spp., G. hollisae results were still clearly distinct from Vibrio spp. RFLP types for all restriction enzymes tested. If restriction enzymes are aptly selected, PCR-RFLP analysis is still a rapid and effective tool for differentiating Vibrio species.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.10
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• pp.899-905
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• 2016

Wireless access in vehicle environment (WAVE) communication is currently being researched as core wireless communication technologies for cooperative intelligent transport systems (C-ITS). WAVE consists of both vehicle to vehicle (V2V) communication, which refers to communication between vehicles, and vehicle to infrastructure (V2I) communication, which refers to the communication between vehicles and road-side stations. V2I has a longer communication range than V2V, and its communication range and reception rate are heavily influenced by various factors such as structures on the road, the density of vehicles, and topography. Therefore, domestic environments in which there are many non-lines of sight (NLOS), such as mountains and urban areas, require optimized communication channel modeling based on research of V2I propagation characteristics. In the present study, the received signal strength indicator (RSSI) was measured on both an experience road and a test road, and the large-scale characteristics of the WAVE communication were analyzed using the data collected to assess the propagation environment of the WAVE-based V2I that is actually implemented on highways. Based on the results of this analysis, this paper proposes a WAVE communication channel model for domestic public roads by deriving the parameters of a dual-slope logarithmic distance implementing a two-ray ground-reflection model.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.199-205
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• 1999

Vibrio vulnificus cytolysin caused platelet cytolysis and increased intracellular calcium concentration $([Ca^{2+}]_i)$ of rat platelets in a concentration-dependent manner. In the presence of V. vulnificus cytolysin (3 HU/ml), lactate dehydrogenase (LDH) activity was increased from $1.3{\pm}0.4%$ of control to $64.3{\pm}3.4%$ in platelet suspension buffer. In $Ca^{2+}-free$ platelet suspension buffer, however, V. vulnificus cytolysin did not induce $[Ca^{2+}]_i$ increase and LDH release. Addition of EGTA (2 mM) to suspension buffer after the initial $Ca^{2+}$ influx reversed $[Ca^{2+}]_i$ to the control level. However, a $Ca^{2+}$ channel blocker verapamil $(20\;{\mu}M)$ or mefenamic acid $(20\;{\mu}M)$ did not inhibit V. vulnificus cytolysin-induced $[Ca^{2+}]_i$ increase and LDH release. Divalent cations such as $Co^{2+},\;Cd^{2+}\;or\;Mn^{2+}$ (2 mM each) also did not alter V. vulnificus cytolysin-induced $[Ca^{2+}]_i$ increase and LDH release. V. vulnificus cytolysin (3 HU/ml)-induced calcium influx was completely blocked by lanthanum (2 mM). Lanthanum (2 mM) also completely blocked V. vulnificus cytolysin (3 HU/ml)-induced LDH release. Osmotic protectants such as, raffinose, sucrose or PEG600 (50 mM each) did not inhibit the lytic activity of V. vulnificus cytolysin. In conclusion, lanthanum sensitive $Ca^{2+}$ influx plays a significant role in Vibrio vulnificus cytolysin-induced platelet cytolysis and thrombocytopenia in V. vulnificus infection.

• Journal of radiological science and technology
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• v.7 no.1
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• pp.85-92
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• 1984

It is a esperimental report to investigation for optimum window-width on radionuclides $^{131}I\;and\;^{198}Au$ The obtained results were as follow; 1. In case of $^{131}I$, 1) The lowest counts produced at the window-width of 10KeV and 20KeV. 2) The count rate, more increased, when the window-width more opened, but the counting efficiency is very good between 70KeV and 130KeV window-width (19.23% -35.71% about the peak energy). 3) The heighest counting rate per KeV of window appeared at 130KeV window-width. 4) BKG counts increased proportionally to the wider window as 5.473 + 0.016 cpm. 2. In case of $^{198}Au$ 1) The lowest counts appeared at 10KeV and 20KeV window. 2) Count rate more increased, when window-width more opened, but the counting efficiency is very good between 80KeV and 140KeV window (19.46% - 34.06% about the peak energy). 3) The highest counting rate per KeV of the window appeared at 140KeV window. 4) BKG counts increased proportionally to the wider window-width as 4.74 + 1.09 cpm.

• Journal of Astronomy and Space Sciences
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• v.25 no.2
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• pp.87-100
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• 2008

A total of 792 CCD images of V523 Cas were obtained on four nights of Jan. 2003 with the bvri CCD photometric system attached to a 61cm reflector of Sobaeksan Optical Astronomy Observatory (SOAO). The 17 standard stars in the images were used to establish transformation relations between our bvri system and the standard Johnson-Cousins BVRI system. We derived the tentative equations of transformation between two photometric systems as follows; V=v-0.0689(B-V)+0.0063, B-V=1.3197(b-v)-0.1733, V-R=0.9210(v-r)-0.1309, R-I=0.8892(r-i)-0.1055. Using these equations standard V magnitudes and their color indexes (B-V, V-R, R-I) for 57 stars in the field of the image were determined.