• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.10C
• /
• pp.749-757
• /
• 2008

In this paper, we propose an authentication scheme for EVPT (Emergency Vehicle Priority Transit) service in Vehiclar Ad-hoc Networks (VANET) enable a variety of vehicle comfort services, traffic management applications, and infotainment services. These are the basis for a new generation of preventive and active safety functions. By intelligently controlling signalling at intersections, providing additional information to the driver and warning the driver in critical situations. we therefore focus on vehicle-to-infrastructure communication for the authentication between emergency vehicles and traffic lights system. This authentication process should identify the vehicle, and provide privacy protection.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2005.05a
• /
• pp.283-287
• /
• 2005

In this paper, one general approach is proposed for the design of power system that can be applicable for next generation LEO satellite application. The power system consists of solar panels, battery, and power control and distribution unit(PCDU). The PCDU contains solar array modules, battery interface modules, low-voltage power distribution modules, high-voltage distribution modules, heater power distribution modules, on-board computer interface modules, and internal DC/DC converter modules. The PCDU plays roles of protection of battery against overcharge by active control of solar array generated power, distribution of unregulated electrical power via controlled outlets to bus and instrument units, distribution of regulated electrical power to selected bus and instrument units, and provision of status monitoring and telecommand interface allowing the system and ground operate the power system, evaluate its performance and initiate appropriate countermeasures in case of abnormal conditions. We review the functional schemes of the main constitutes of the PCDU such as the battery interface module, the auxiliary supply module, solar array regulators with maximum power point tracking(MPPT) technology, heater power distribution modules, spacecraft unit power distribution modules, and instrument power distribution module.

• Current Research on Agriculture and Life Sciences
• /
• v.31 no.2
• /
• pp.101-107
• /
• 2013

This study was undertaken to determine free radical scavenging capacity and oxidative DNA damage protecting activity of methanol extract of red tea stem. The extract was subjected to assess their antioxidant potential using various in vitro systems such as $DPPH^{\bullet}$, $ABTS^{{\bullet}+}$, super oxide and nitric oxide free radicals and it exhibited $IC_{50}$ values of $68.88{\pm}1.1$, $12.08{\pm}0.65$, $404.38{\pm}1.6$, $93.6{\pm}2.7{\mu}g/mL$ respectively. Red tea extract also showed ferric reducing ability (FRAP) with 2606.85 mmol Fe (II)/g of extract. Furthermore, Methanol extract of red tea stem showed significant DNA damage protecting activity in concentration dependent manner against $H_2O_2+UV$ induced photolysis on pUC19 plasmid DNA. Results of this study showed that the methanol extract of Red Tea stem has strong antioxidant potential along oxidative DNA damage protecting capacity that would be the significant sources of natural antioxidants, which might be helpful in preventing the progress of various oxidative stress generated diseases. Further study is necessary for isolation and characterization of the active antioxidants, which may serve as a potential source of natural antioxidant.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.1
• /
• pp.62-69
• /
• 1999

In order to investigate the critical amino acid residues involved in the catalytic activities of $\beta$-cyclodextrin glucanotransferase ($\beta$-CGTase) excreted by Bacillus firmus var. alkalophilus, the amino acid residues in $\beta$-CGTase were modified by various site-specific amino acid modifying reagents. The cyclizing and amylolytic activities of $\beta$-CGTase were all seriously reduced after treatment with Woodward's reagent K (WRK) modifying aspartic/glutamic acid, N-bromosuccinimde (NBS) modifying tryptophan, and diethylpyrocarbonate (DEPC) modifying histidine residues. The roles of tryptophan and histidine residues in $\beta$-CGTase were further investigated by measuring the protection effect of various substrates during chemical modification, comparing protein mobility in native and affinity polyacrylamide gel electrophoresis containing soluble starch, and comparing the $K_m$ and $V_{max}$ values of native and modified enzymes. Tryptophan residues were identified as affecting substrate-binding ability rather than influencing catalytic activities. On the other hand, histidine residues influenced catalytic ability rather than substrate-binding ability, plus histidine modification had an effect on shifting the optimum pH and pH stability.

• Journal of the Korean Institute of Rural Architecture
• /
• v.20 no.3
• /
• pp.47-56
• /
• 2018

This study is to research the military remains of Korean War(1950~53) focused on Yeonchen, Cheorwon, and Hwacheon-gun in the central border of DMZ. The Yeoncheon-gun is installing 'Yeolsoe' and 'Taepung' observatory in the frontline battlefield adjacent to Southern Limit Line(SLL), and not only protects many military remains including war memorial and crematory facilities of UN troops, but also utilizes them as active educational places. The Cheorwon-gun is actively making known 'Baengmagoji memorial, 'Labor party office' and other buildings adjacent to 'Tourist security DMZ', but needs to set up many monuments around battlefields of 'Gimhwa' and 'Daeseongsan' adjacent to 'Eco-peace park DMZ'. With the battlefield of 'Paroho' as the center, which our troops made brilliant military gains during the war, the Hwacheon-gun protects and informs military remains such as '643 and 490 battlefields', 'Kkeomeok and Guman bridge'. Developing a network for military remains in connection with the annual local festivals, the experience tour and security will be available at these places.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.8
• /
• pp.1519-1528
• /
• 2017

Foodborne contamination and salmonellosis caused by Salmonella Enteritidis (S. Enteritidis) are a significant threat to human health and poultry enterprises. Outer membrane vesicles (OMVs), which are naturally secreted by gram-negative bacteria, could be a good vaccine option because they have many biologically active substances, including lipopolysaccharides (LPS), outer membrane proteins (OMPs), and phospholipids, as well as periplasmic components. In the present study, we purified OMVs derived from S. Enteritidis and analyzed their characteristics through silver staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis. In total, 108 proteins were identified in S. Enteritidis OMVs through liquid chromatography tandem mass spectrometry analysis, and OMPs, periplasmic proteins, and extracellular proteins (49.9% of total proteins) were found to be enriched in the OMVs compared with bacterial cells. Furthermore, native OMVs used in immunizations by either the intranasal route or the intraperitoneal route could elicit significant humoral and mucosal immune responses and provide strong protective efficiency against a lethal dose (~100-fold $LD_{50}$) of the wild-type S. Enteritidis infection. These results indicated that S. Enteritidis OMVs might be an ideal vaccine strategy for preventing S. Enteritidis diseases.

• Proceedings of the SCSK Conference
• /
• 2003.09a
• /
• pp.85-96
• /
• 2003

Normal human skin, constantly challenged by environmental micro-organisms, has an innate ability to fight invading microbes through antimicrobial peptides. These peptides, described in both plant and animal kingdoms are able to inactivate a broad spectrum of micro-organisms. Mammalian defensins constitute one of the most common antimicrobial peptide family. Among the three human beta-defensins hBD1, hBD2 and hBD3 produced in epithelia, only hBD2 and hBD3 are inducible and additionally have been described as expressed by differentiated keratinocytes at site of inflammation and infection. The aims of these studies were to define a cell culture model in which the basal production of hBD could be detected and up-regulated in order to enhance skin auto-protection against micro-organisms. A specific Polymerase Chain Reaction method have been developed for hBD2 and hBD3 mRNA detection in non-differentiated monolayer keratinocytes cell culture. We have been able to demonstrate that in vitro, hBD2 and hBD3 expression in normal human keratinocytes could be detected and enhanced by TNF-alpha and IFN-gamma, in hypercalcic culture conditions. This research opened the possibility of the development of cosmetic active compounds, able to induce the expression of skin natural antibiotic peptides responsible about microflora ecology of the skin.

• Asian Journal of Innovation and Policy
• /
• v.9 no.1
• /
• pp.56-78
• /
• 2020

Changes in our lives due to Artificial Intelligence (AI) are currently ongoing, and there is little refutation of the effectiveness of AI. However, there have been active discussions to minimize the side effects of AI and use it responsibly, and publishing the AI Charter of Ethics (AICE) is one result of it. This study examines how our society is responding to threats from AI that may emerge in the future by examining various AIECs in the Republic of Korea. First, we summarize seven AI threats and classify these into three categories: AI's value judgment, malicious use of AI, and human alienation. Second, from Korea's seven AICEs, we draw fourteen topics based on three categories: protection of social values, AI control, and fostering digital citizenship. Finally, we review them based on the seven AI threats to evaluate any gaps between the threats and our responses. The analysis indicates that Korea has not yet been able to properly respond to the threat of AI's usurpation of human occupations (jobs). In addition, although Korea's AICEs present appropriate responses to lethal AI weapons, these provisions will be difficult to realize because the competition for AI weapons among military powers is intensifying.

• Journal of the Optical Society of Korea
• /
• v.16 no.1
• /
• pp.1-5
• /
• 2012

This paper describes a 150-Mb/s monolithic optical receiver for plastic optical fiber link using a standard CMOS technology. The receiver integrates a photodiode using an N-well/P-substrate junction, a pre amplifier, a post amplifier, and an output driver. The size, PN-junction type, and the number of metal fingers of the photodiode are optimized to meet the link requirements. The N-well/P-substrate photodiode has a 200-${\mu}m$ by 200-${\mu}m$ optical window, 0.1-A/W responsivity, 7.6-pF junction capacitance and 113-MHz bandwidth. The monolithic receiver can successfully convert 150-Mb/s optical signal into digital data through up to 30-m plastic optical fiber link with -10.4 dBm of optical sensitivity. The receiver occupies 0.56-$mm^2$ area including electrostatic discharge protection diodes and bonding pads. To reduce unnecessary power consumption when the light is not over threshold or not modulating, a simple light detector and a signal detector are introduced. In active mode, the receiver core consumes 5.8-mA DC currents at 150-Mb/s data rate from a single 3.3 V supply, while consumes only $120{\mu}W$ in the sleep mode.

• International Journal of Oral Biology
• /
• v.39 no.1
• /
• pp.9-13
• /
• 2014

Streptococci are among the normal human microflora that populate the oral cavity. However, oral streptococci are known as a major causative agent for dental caries and bacterial endocarditis. Tetracycline is a broad-spectrum antibiotic that is used for oral infections but two mechanisms of tetracycline resistance in streptococci have been reported. The tet(K) and tet(L) genes in these bacteria are related to the active efflux of tetracycline, whereas tet(M) and tet(O) confer ribosomal protection from this antibiotic. It has been reported that the tetracycline resistance of streptococci is related mainly to the activity of tet(M) and tet(O). In our present study, we examined the prevalence of tet(M) and tet(O) in oral streptococci isolated from Korean dental plaques using PCR. One hundred and forty eight of 635 isolates (23.3%) were tetracycline resistant; 68 of these strains (46%) harbored tet(M) and 3 strains (2%) were positive for tet(O). However, tet(M) and tet(O) did not co-exist in any of the resistant strains. Seventy seven of the 148 tetracycline resistant strains (52%) were negative for both the tet(M) and tet(O) genes.