• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.838-847
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• 2017

CNG which was released as a substitute of the previous CAPI (Cryptography API) library from Microsoft is constructed with individual modules based on the plug-in architecture, this means CNG is exceedingly helpful in the cost of development as well as the facility of extension. On the opposite side of these advantages, considerations on security issues are quite insufficient. Therefore, a research on security assurance is strongly required in the environment of distributing and utilizing the CNG library, hence, we analyze possible security vulnerabilities on the CNG library. Based on analyzed vulnerabilities, proof-of-concept tools are implemented and vulnerabilities are verified using them. Verified results are that contents of mail, account information of mail server, and authentication information of web-sites such as Amazon, E-bay, Google, and Facebook are exposed in Outlook program and Internet Explorer program using CNG library. We consider that the analyzed result in this paper can improve the security for various applications using CNG library.

• Journal of the Korean Institute of Gas
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• v.15 no.2
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• pp.21-26
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• 2011

Emissoin of heavy duty vehicle have much positioned in air pollution although its limited number of vehicles. CNG vehicles are coming to the fore as one of the solution of diesel vehicles. CNG vehicles exhaust smaller emission than diesel vehicles on PM and NOx. In this study, aftertreatment technologies are introduced on vehicles which use CNG and hydrogenmixed fuel. Withmixing hydrogen with CNG, combustion efficiency is enhanced, and harmful emission might be decreased, but methane that is main component of CNG brings green house effect. In order to remove methane and NOx in exhaust gas of CNG engine, methane oxidation catalyst and SCR technologies were respectively analyzed.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.28-33
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• 2015

In this study, a dual fuel engine fueled with natural gas and diesel was tested to investigate the effects of heating value variation of CNG fuel. CNG substitution rate which is defined as the ratio of CNG and diesel supplied in a heating value basis was fixed at 80%. The higher heating value was varied from $10,400kcal/Nm^3$ to $9,400kcal/Nm^3$ by mixing nitrogen gas with pure CNG and diesel fuel was injected at a fixed injection timing. The engine test results showed that thermal efficiency and power output were decreased as the heating value of mixed CNG fuel was decreased. And the peak cylinder pressure was also decreased but the ignition delay time and the combustion duration and timing were almost same.

• Clean Technology
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• v.15 no.1
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• pp.1-8
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• 2009

The adoption of compressed natural gas (CNG) as a vehicle fuel is a common phenomenon as it is accelerating worldwide. Increasing number of CNG driven vehicles around the world has jumped up from one million in 1996 to five million in 2006. CNG as a vehicle fuel is very popular to the end users because of its clean-burning properties and cost effective solution compared to other alternative fuels like diesel and gasoline. The use of CNG as a fuel reduces vehicular emission that is consisted of carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen ($NO_x$), carbon dioxide ($CO_2$) etc. This research highlights the characteristics of CNG vehicles, CNG arrangement in the vehicles, CNG fueling procedures and most importantly the environmental and economic factors that are highly considered as cost effective solution for the flexibility of using CNG in the automobiles.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.2
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• pp.16-28
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• 1990

본 고에서는 CNG차량에 대한 해외의 동향과 자동차 대체연료로서의 CNG의 특성 및 CNG차량에 대한 구조, 성능 및 안전성에 대하여 검토 소개한다. 근년 자동차용 대체연료로서의 관점은 저공해성이 중요하게 부각되고 잇다. 이에 따라 국내의 대도시환경오염 방지를 위한 한가지 방안으로서 CNG의 채용이 활발하게 논의되어오고 있다.

• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.56-61
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• 2011

For the prevention of air pollution, the CNG vehicles have been supplied since 2006. The spread of CNG vehicles has decreased the level of air pollution. Declared goals of Korean Ministry of Environment (ME) are to supply CNG city bus by 90% by 2012. CNG bus explosion has exacerbated commuters' safety concerns, it has caused the barrier to the installation of CNG station. In this study, the sensor was installed for the safety improvement of CNG station. When new sensors were installed, a problem was encountered by a line of communication. To solve the installation problem, we carried out the monitoring of data communication network by USN technology.

• Journal of the Korean Institute of Gas
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• v.4 no.3 s.11
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• pp.53-58
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• 2000

It was carried out consequence analysis(CA) of CNG (compressed natural gas) service station and we compared the results of CA of CNG service station with LPG service station which was installed by high Pressure gas law. The results of CA were that distance of CNG LFL was 1.5 times than the length of LPG LFL. Thermal radiation effect about CNG may not be showed damage of process facilities, but in the case of LPG, it was enough to have an large damage effect on a downtown. The thermal radiation of 37.5 $kw/m^2$ extended 12.6 m. Also, in the case of 12.5 $kw/m^2$ which was able to burn wood, the radiation effect of LPG is 3 times than CNG.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.2
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• pp.142-147
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• 2011

Compressed natural gas (CNG) is well known as one of the cleanest burning alternative fuels. Bi-fuel CNG vehicle can also run on gasoline or another fuel while dedicated natural gas vehicle is designed to run on natural gas only. Recently, increased attention has been focused on bi-fuel CNG/LPG taxi because of good fuel economy of CNG. A number of LPG taxis modified to CNG Bi-fuel vehicles are running in many cities. In this paper, the emissions characteristics of in-use passenger cars running on CNG and LPG were investigated. Chassis dynamometer test was used to measure exhaust emissions from an in-use fleet of 5 cars. Exhaust emissions were collected for CVS-75 driving mode. The test results showed that for CNG fuel mode, CO, $CO_2$ and NMHC emissions decreased to 9%, 12% and 14% respectively, and $CH_4$ and $NO_x$ emissions increased to 317% and 47% respectively.

• Journal of ILASS-Korea
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• v.19 no.1
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• pp.33-39
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• 2014

Due to persist of high oil prices, LPG price stabilization and CNG modification project will be conducted. Present study describes the fuel efficiency and $CO_2$ emission characteristics on driving cycle mode and ignition advance condition change of CNG/LPG Bi-Fuel vehicle. In case of LPG Base and CNG Base condition, considerable $CO_2$ emissions are generated within range of high acceleration on FTP-75 and HWFET driving mode. However previous phenomena does not appear in CNG fuel $10^{\circ}CA$ and $15^{\circ}CA$ spark advance condition. As a result of analyzing the experimental data CNG $S/A10^{\circ}CA$, CNG $S/A15^{\circ}CA$, CNG Base, and LPG Base sequentially measured high fuel economy and low $CO_2$ emission characteristics.

• Molecules and Cells
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• v.19 no.1
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• pp.149-154
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• 2005

Cyclic nucleotide-gated (CNG) channels encoded by the tax-4 and tax-2 genes are required for chemosensing and thermosensing in the nematode C. elegans. We identified a gene in the C. elegans genome, which we designated cng-1, that is highly homologous to tax-4. Partial CNG-1 protein tagged with green fluorescent protein was expressed in several sensory neurons of the amphid. We created a deletion mutant of cng-1, cng-1 (jh111), to investigate its in vivo function. The mutant worms had no detectable abnormalities in terms of their basic behavior or morphology. Whereas tax-4 and tax-2 mutants failed to respond to water-soluble or volatile chemical attractants, the cng-1 null mutant exhibited normal chemotaxis to such chemicals and a tax-4;cng-1 double mutant had a similar phenotype to tax-4 single mutants. Interestingly, cng-1 and tax-4 had a synergistic effect on brood size.