• Annual Conference of KIPS
• /
• 2010.04a
• /
• pp.835-838
• /
• 2010

본 논문에서는 공공기관의 효율적인 보안 진단을 위하여 금융 위험평가 시스템에 사용되는 통계적 CAEL 모델을 적용하여 보안평가 모델(SAM)을 설계하였다. SAM은 통계적 CAEL 모델을 기반으로 조직과 관련된 보안변수와 보안지표를 평가요소로 하여 요소별 평가등급 선정 방식과 최종 종합평점 산출 방법으로 보안평가 결과값을 도출한다. SAM은 조직의 보안수준 결과에 중요하게 영향을 미칠 수 있는 모든 요소들을 평가대상으로 하고 정량적인 방법인 보안평가 모델을 활용하여 결과를 산출한다. SAM은 조직의 규모, 특성 등에 따라 보안변수를 변경할 수 있으며, 각 보안 지표별 통계적 자료 값을 수집하여 요구되는 변수만 입력하면 되기 때문에 사용 용이성도 우수하다.

• Annual Conference of KIPS
• /
• 2010.04a
• /
• pp.816-819
• /
• 2010

IT 기술의 발달로 문서의 제작, 관리, 유통, 복사 등이 점차 간단하며 쉬워지고 있다. 또한 네트워크의 발달, 저장매체의 발달로 인해 문서의 불법 복제, 무단 유출, 불법 유통 등도 함께 쉬워지고 있다. 따라서 각종 문서에 대한 보안의 중요성이 부각되기 시작하였다. 이 중 DRM(Digital Right Management)이란 기술이 가장 널리 알려졌으며, 가장 많이 사용되게 되었다. 따라서 많은 DRM 제품이 출시 되었지만 각각 다른 문서 DRM의 경우 어떤 기준없이 개발되어 하나의 PC에서 동작할 수 없는 문제점이 발생하게 되었다. 본 논문에서는 디지털 문서의 대표적인 형태인 Compound Document File Format의 Header를 수정하고, 각 문서 DRM에 고유 식별번호를 부여하여 이와 같은 문제점을 해결하는 방안에 대해 제안하고자 한다.

• Annual Conference of KIPS
• /
• 2010.04a
• /
• pp.146-149
• /
• 2010

IT를 비롯한 여러 분야의 기술과 산업이 발전하면서 단일화된 플랫폼의 기술은 융합화된 다양한 서비스들을 지원할 수 있는 융합 서비스 플랫폼으로 발전하였다. 융합 서비스 플랫폼에서는 수 많은 사업자들이 다양한 콘텐츠 및 네트워크 자원을 제공하면서 수익을 얻게 되는데, 이 때 과금을 처리하기 위한 시스템이 이슈가 되었다. 융합 서비스 플랫폼에서의 서비스는 다양한 서비스들이 융합된 형태를 가지고 있으며, 시간 및 콘텐츠, 사용자에 따른 요금 감면 등 다양한 과금 요소들로 인하여 상당히 복잡하고 다양한 형태를 띄고 있다. 본 논문에서는 융합 서비스 플랫폼에서 과금을 하기 위해서 고려되어야 할 사항에 대해서 정의하고, 융합 서비스와 여러 과금 요소들을 포함하여 과금을 측정할 수 있는 과금 관리 모델을 제안한다. 제안된 과금 모델은 실제 융합 서비스 플랫폼에서 지원하기 위한 아키텍처를 구성하는데, 기본 자료로써 활용될 것이다.

• Annual Conference of KIPS
• /
• 2009.11a
• /
• pp.705-706
• /
• 2009

본 논문은 향후 임베디드 단말 기기에 탑재되어 실행되는 응용 애플리케이션들이 제 3 자에 의해 개발되어 앱스토어를 통해 배포될 경우, 신뢰성 및 보안 문제 해결을 위해 제 3 자 개발자에 의해 개발된 애드온 애플리케이션들의 접근통제 메커니즘에 대해 연구하였다. 본 논문에서는 태스크-플로우 기반 메쏘드 접근제어 모델을 제시하고, X.509 기반의 권한 관리 구조를 통해 임베디드 단말에서 애드온 프로세스의 접근 통제를 위한 구조를 디자인하였다

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.11 no.3
• /
• pp.81-91
• /
• 2012

The world has been replacing fast fossil fuels vehicles with electric vehicles(EVs) to cope with climate change. The government set a goal which EVs will be substitute at least 10% of the domestic small vehicles with EVs until 2020, and will try to build electric charging infrastructures in apartments with the revision the law of 'the housing construction standards'. In apartments the EVs charging infrastructure and parking space is, essential to accomplish the goal. But the studies on EVs demand are few. In this study, we predicted that the demand for EVs using time-series analysis of statistical data, survey results for apartments residents in the metropolitan area. As a result, the ratio of the EVs appeared to be 6~21% for the total vehicles in a rental apartments for the years 2020, 21~39% in apartments for sales. For the EVs, the maximum power required for 1,000 households in rental apartment is predicted to be about 4200 kwh on a daily basis, while the maximum power in the apartment for sales is predicted to be 7800kwh.

• Environmental and Resource Economics Review
• /
• v.21 no.3
• /
• pp.595-625
• /
• 2012

Recently environment-friendly pellet boilers have interests as emissions of greenhouse gases are regulated internationally and energy security becomes more important to oil addicted countries including Republic of Korea. But the Korean market for pellet boilers is on the initial stage due to the high production costs relative to other conventional boilers. Hence the Korean government has supported financially and promoted the pellet boiler business. In this sense, it would contribute market stratergy and effective promotion policy for both of the government and private companies if we can forecast market shares of pellet boilers appropriately. For this purpose, this study surveyed potential consumers' preferences on pellet boilers among various alternatives using a choice experiment reflecting intangible costs. As the market share of new technology increases, intangible costs decline. According to different intangible cost scenarios, we experimented people's preferences on oil, gas, electric, and pellet boilers. A multinomial logit model was employed to estimate coefficient parameters of common attributes for various alternative boilers. Based on the estimates, we forecasted market shares of individual boilers. We found that as intangible costs decline, the market share of pellet boiler increase substantically while market shares of electric and gas boilers decrease dramatically. The market share of oil boiler did not change significantly. Meanwhile, as people are more rich, more educated, and exposed to advertisement on pellet boilers, the likelihood of choosing the pellet boiler increases.

• Korean Journal of Ecology and Environment
• /
• v.38 no.4 s.114
• /
• pp.482-493
• /
• 2005

The objective of this research was to evaluate an sampling effect of fish species and individual number on sampling techniques of electrofishing and conventional capture methods of cast net and kick net in 38 stream sites sampled during June - September, 2005. For the study, sampling gears were categorized as three types of electrofishing method (EM), conventional sampling technique (CM), and the combined technique (CT) of the electrofishing and the conventional method to compare statistical differences. Major differences of species composition between the CM and EM method were found in some benthic species of Misgurnus mizolepis and Iksookimia koreensis along with lithophilic species of Pungtungia herzi. These species were predominated in the EM rather than the CM, indicating that conventional sampling can underestimate the abundance of benthic or lithophilic species. In contrast ,individual number of typical water column species such as Zacco platypus and Zacco temmincki were more sampled by the CM, so that these fish populations were community overestimated. Also, t-tests on the types of sampling gear from various watersheds of Chogang Stream, Yugu Stream, Daejeon Stream, and Gap Stream showed that total individual numbers and species number in each stream were significantly (t values = 2.806-6.896, p values<0.05, n = 5-14) greater in the CT than the CM. Similar statistical significance (p<1.001, n = (10-24) on sampling seasons were observed during the monsoon and postmonsoon. These results indicate that if the electrofishing is not added to the conventional gears, the abundance of fish population and community can be underestimated and some benthic or lithophilic species may be excluded from the analysis, resulting in overall errors including sampling, fish fauna, and final judgement of community abundance. Overall our results strongly suggest that new application of electrofishing method along with the conventional sampling gears reduce sampling bias on underestimation of the real fish populations and communities.

• Journal of Biomedical Engineering Research
• /
• v.20 no.2
• /
• pp.205-212
• /
• 1999

When we want to observe and record a patient's EEG in an operating room, the operation of electrosurgical unit(ESU) causes undesirable artifacts with high frequency and high voltage. These artifacts make the amplifiers of the conventional EEG system saturated and prevent the system from measuring the EEG signal. This paper describes a high-performance bipolar EEG amplifier for a CSA (compressed spectral array ) system with reduced ESU artifacts. The designed EEG amplifier uses a balanced filter to reduce the ESU artifacts, and isolates the power supply and the signal source of the preamplifier from the ground to cut off the current from the ESU to the amplifier ground. To cancel the common mode noise in high frequency, a high CMRR(common mode rejection ratio) diffferential amplifier is used. Since the developed bipolar EEG amplifier shows high gain, low noise, high CMRR, high input impedance, and low thermal drift, it is possible to observe and record more clean EEG signals in spite of ESU operation. Therefore the amplifier may be applicable to a high-fidelity CSA system.

• The Journal of the Acoustical Society of Korea
• /
• v.31 no.7
• /
• pp.480-486
• /
• 2012

In the design of electro acoustic transducer, power factor improvement circuit is more required rather than impedance matching if the driving power amplifier has little inner resistance. Many research results have been focused on the power matching circuit designing for transferring maximum power in the wideband. There are few results in the designing study on the power factor improvement for the wide band electro acoustic transducer. In this paper, we propose a new design method on the power factor improvement for the wide band electro acoustic transducer. The proposed method consists of two steps, the chebyschev matching method and the constrained optimization, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.23 no.12
• /
• pp.966-972
• /
• 2010

Single-phase $Sr_2FeMoO_6$ thin films were produced by RF magnetron sputtering for use as electrodes in integrated sensors and found to be good conductors at room temperature. The films were deposited from a powder-type sputtering target under various conditions, and were crystallized by annealing. Elimination of $O_2$ gas during deposition, by the use of a solely Ar sputtering gas under a working pressure as low as possible, and vacuum annealing were important to promote the $Sr_2FeMoO_6$ phase. However, oxygen exclusion from sputtering and annealing was not enough to yield single-phase $Sr_2FeMoO_6$: hydrogen annealing was also required. Film production was optimized by varying the deposition parameters and hydrogen annealing conditions. The film had good electrical conduction, with a low resistivity of $1.6{\times}10^{-2}\Omega{\cdot}cm$ at room temperature.