• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.2
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• pp.184-190
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• 2002

This study was undertaken to judge the quality of air-tightened exhibition cases. Exhibition cases for artifacts display provide a layer of protection between the interior conditions in the exhibition case and the exterior fluctuating conditions of temperature and relative humidity in the museum environment. An infiltration model of the exhibition case was developed through the experimental measurements to calculate the number of air change rate in the exhibition case undergoing in a day, which represents the airtightness of the exhibition case. The results indicate that tighter exhibition cases provide greater protection against the fluctuating conditions of temperature and humidity outside. When the temperature and humi- dity difference between the exhibition case in-and-out is larger, some absorption materials should be applied to control the environmental conditions in the exhibition case.

• Journal of the Korean Solar Energy Society
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• v.25 no.4
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• pp.61-67
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• 2005

The purpose of this study is to evaluate the air tightness of Zero Energy Solar House(ZeSH) and to propose the construction improvement of junctions and penetrations where air infiltration was identified. Air leakage rate were measured by means of blower door test in accordance with ASTM E779-87. The results showed that ZeSH has an excellent airtightness with ACH50/20 (air change per hour at a pressure difference of 50 Pa between inside outside) of 0.34hr-1 and leakage class E by normalized leakage area of ASHRAE.

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.65-71
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• 2008

The purpose of this study is to investigate an airtightness of typical Korean detached houses with field measurements. Air leakage testings by means of blower door test in accordance with ASTM E79-8 were measured in 22 detached dwellings in Daejeon and Geumsan. The results showed that detached dwellings have an average airtightness with ACH50/20 (air chang per hour at a pressure difference of 50 Pa between inside outside) of 0.82 $hr^{-1}$ which is a higher range than for typical apartments and leakage class G by normalized leakage area of ASHRAE.

• Convergence Security Journal
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• v.11 no.4
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• pp.31-36
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• 2011

Enterprise which has a core technology or organization which manages a core information will be walking into a critical situation like a ruins when organization's confidential information is outflowed. In the past confidential information that was leaked to the off-line, recently the outflow made possible through a variety of equipment at any time via the network based on the ubiquitous communication environment. In this paper, we propose to authenticate and block all packets transmitted via the network at real-time in order to prevent confidentials outflow. Especially in or der to differentiate between users who attempt to disclose confidentials, we propose to insert user's biometric informaion transparently at per-packet basis, and also verify a performance by simulation.

• Journal of Korea Multimedia Society
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• v.16 no.12
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• pp.1427-1438
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• 2013

We have developed a 128-bit stream cipher algorithm composed of the 5-stage pipeline, capable of real-time processing, confidentiality and integrity. The developed stream cipher is a stream cipher algorithm that makes the final 128-bit ciphers through a whitening process after making the ASR 277 bit and SHACAL-2 and applying them to the CFB mode. We have verified the hardware performance of the proposed stream cipher algorithm with Modelsim 6.5d and Quartus II 12.0, and the result shows that the hardware runs at 33.34Mhz(4.27Gbps) at worst case. According to the result, the new cipher algorithm has fully satisfied the speed requirement of wireless Internet and sensor networks, and DRM environment. Therefore, the proposed algorithm with satisfaction of both confidentiality and integrity provides a very useful ideas.

• KIEAE Journal
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• v.15 no.2
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• pp.109-115
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• 2015

Purpose: The importance of building airtightness is increased as the demand and expectation of building energy efficiency is growing. Previous research only focused on airtightness of building openings only to improve building airtightness. However, the analysis of difference of airtightness performance according to the characteristic of building structure has not been performed. Therefore, this study analyzed the difference of airtightness performance according to building structural characteristics in a number of ways. Method: Airtightness that are classified as rigid-frame type or wall type are measured and analyzed the difference of airtightness performance between rigid frame type apartments and wall type apartments. This study calculated the heating energy demand and quantitatively analysis using ISO 13790. Futhermore, this study compared research trend of domestic airtightness performance with airtightness standards of the developed countries based on the field measurement. Result: Airtight performance of wall type is better than rigid frame type in terms of energy saving. The difference of heating energy demand between wall type and rigid frame type was $8.14kWh/m^2yr$.

• KIEAE Journal
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• v.14 no.5
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• pp.117-121
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• 2014

Even though a study of airtightness performance of apartment and detached house have been done constantly, there are few of studies of multi-family housing which increasing every year. Therefore, this study analyzed airtightness performance of 20 households of one room in Daejeon to investigate airtightness performance standard. All experiments were performed under the same conditions except sealing windows to investigate airtightness performance without sealing windows (natural condition) and airtightness performance with sealing windows of studio apartment. As results, (1) average ACH50 without sealing windows was 19.2/h for pressurization, and 12.8/h for depressurization and (2) average ACH50 with sealing windows was 16.0/h for pressurization, and 10.7/h for depressurization and ACH50 in both condition, ACH50 under pressurization was about 50% higher than that under depressurization. Throughout this experiment, we can figure out that about 16% of air infiltration rate is occurred in windows, and the other 84% is occurred in rest of places such as Junction structure, socket and ventilating opening.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.72-75
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• 2001

전력케이블 선로에 가해지는 전압은 상시교류전압이외에 지락 등에 의한 사용주파과전압과 뇌써지와 같은 써지성 과전압이 있다. 써지성 과전압이 케이블 심선에 침입할 경우 종단접속부나 절연접속함의 접속점은 절연통 양단 및 시스와 대지간에 고전압이 발생하여 케이블심선-시스간 시스-대지간의 써지임피던스 비에 따라 과전압이 발생하며, 이와 같이 써지성 과전압이 방식층의 충격내전압치를 초과할 경우 방식층을 보호하기 위한 대책이 필요하며 그 보호장치로 절연통 보호장치를 사용하는 것이 일반적이다. 절연통에 대한 보호대책과, 설계 제작된 절연통 보호장치에 대한 주요시험항목을 실시하여 항목별 그 특성을 검토하고 절연통 보호장치의 지중송전선로에서 사용되는 조건인 열적내량을 검증하는 충격전류시험과 침수에 의한 기밀성능을 검증하는 내수성능시험을 실시함으로써 그 중요성을 인식할 수 있었다.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.376-385
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• 2003

본 논문에서는 인터넷을 이용한 DLC 시스템의 보안 방안에 대한 연구와 제안된 시스템의 성능평가 내용을 기술한다. 이 논문에서는 DLC 시스템만이 아닌 다양한 제어 시스템에서의 보안 시스템 구성이 가능한 방법을 제안하였다. DLC 시스템의 보안 요소는 데이터 기밀성과 무결성, 부인 방지, 제어장치와 서버간의 상호인증이다. 데이터 기밀성과 무결성은 SSL을 통해서 해결하고 제어장치와 서버간의 상호인증은 PKI 서명을 통해서 해결하였다. 또한, DLC 시스템과 같은 close system에서 사설 PKI의 사용을 통한 시스템 성능향상에 대해 살펴본다.

• KIEAE Journal
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• v.14 no.3
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• pp.87-95
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• 2014

The purpose of this study is to evaluate the correlation coefficients between the airtightness and sound insulation performance of Han-style windows in New Han-ok. To achieve these goals, field measurements were accomplished in 18 bedrooms of 16 Han-oks in which actual residents were living, and then lab measurements were proceeded in the reverberation lab for evaluating the sound insulation performance. Followings are results. The results of the correlation analysis between the airtightness(Air change per hour at 50 Pa, ACH50) and sound insulation performance(Sound reduction index, Rw) in bedrooms of actual Han-oks, it was found that there were no significant correlation between two evaluating values. On the other hand, it was analyzed that the correlation coefficients of total 24 structures(double casement windows, single casement window, casement and sliding windows, single sliding window, 6 types per each structure) were located on 0.6757 exponentially and 0.4154 lineary in the lab evaluating conditions. But, The results of evaluating 4 structure classificatorily, it was found that there were high correlation coefficients(0.8665~0.9273 at ACH50, 0.8414~0.9346 at Rw). These results were signified that the correlation coefficients were changed according to the each structure and case by case analysis were necessary at the same time.