네트웍상에서 안전한 정보 공유에 관한 연구

이정기,노정희,홍성표,조애리,이준 조선대학교 전자정보통신연구소 2002 電子情報通信硏究所論文誌 Vol.5 No.2

인터넷이 인류사에 등장한 것은 지금으로부터 30년에 불과 하다. 인터넷은 개방성과 공개성 그리고 수평성을 지향한다. 이러한 특성을 기반으로 해서 인터넷은 디지털 경제를 구체화시키고 실현시키는 중요한 수단이 되고 있다. 현재 주목받고 있는 P2P(Peer-to-Peer)는 인터넷의 이러한 이상을 실현해 가는데 중요한 위치를 차지하고 있다. 개인과 개인간의 정보공유 모델인 P2P는 인터넷을 통해서 다른 사용자들과 정보를 주고받을 수 있는 기술을 말한다. 또한 컴퓨터 네트워크를 통해서 교환되는 정보의 양의 증가와 함께 네트워크의 보안성이 새로운 문제점으로 부각되고 있다. 네트웍에 있는 어떤 사용자가 제한하기 위해서공개된 환경에 있다고 가정하면, 각 사용자간에 허가받은 사용자에게만 접속을 는 서비스에 대한 요구를 인증 해야한다. 본 논문에서는 이를 해결하기 위해 P2P 환경에서 보안을 유지하는 방법을 제안하고, P2P 환경에서 안전하게 정보를 공유할 수 있는 메커니즘으로 Kerberos 인증 메커니즘을 인용하여 인증 메커니즘을 설계하였다. It is not more in 30 years from now that internet appears to history of man.Internet intends patency and patency and horizontal. According as progress by information society, computer network use and enlargement of scale are accelerated more. Also, with good physician increase of information that is exchanged through computer network, security of network is embossed to controversial point that is new. Because P2P as that remove or weakens center server function is open network that can participate between each user, problem about authentication between each users is risen. If certain user in network is in open environment, this user must authenticate request about service to user who is admitted between each user to limit connection. This treatise proposed method to keep security in P2P environment to solve this and designed certification mechanism that quote Kerberos certification mechanism to mechanism that can share information safety in P2P environment.

Bridge Health Evaluation System based on the Optimal BP Neural Network

Hong Ai,Shuai Guo 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.1

Identification of a novel circularized transcript of the AML1 gene

Ai Ning Xu,Xiu Hua Chen,Yan Hong Tan,Xi Ling Qi,Zhi Fang Xu,Lin Lin Zhang,Fang Gang Ren,Si Cheng Bian,Yi Chen,Hong Wei Wang 생화학분자생물학회(구 한국생화학분자생물학회) 2013 BMB Reports Vol.46 No.3

The Contact Lens Related Case Reports In Pediatric Population 1

Ai Hong Chen,Douk Hoon Kim(김덕훈) 한국안광학회 2004 한국안광학회지 Vol.9 No.1

Correlation between Non-Alcoholic Fatty Liver Disease and Visceral Adipose Tissue in Non-Obese Chinese Adults: A CT Evaluation

Ai-Hong Yu,Yang-Yang Duan-Mu,Yong Zhang,Ling Wang,Zhe Guo,Yong-Qiang Yu,Yu-Sheng Wang,Xiao-Guang Cheng 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.5

Objective: To investigate the correlation between non-alcoholic fatty liver disease and visceral adipose tissue in non-obese Chinese adults using computed tomography (CT). Materials and Methods: The study included 454 subjects undergoing abdominal CT scan. Degree of CT attenuation in liver and spleen, and the degree of fat infiltration in liver were evaluated according to three indices: the attenuation value of liver parenchyma (CTLP), the attenuation ratio of liver and spleen (LSratio) and the attenuation difference between liver and spleen (LSdif). Visceral fat area (VFA) and total fat area (TFA) at L2/3 and L4/5 levels were measured, and the abdominal subcutaneous fat area (SFA) was calculated. Bivariate correlation analysis was carried out to determine the correlation among these factors. Results: In men, VFA, SFA and TFA at L2/3 and L4/5 levels showed significant differences in terms of the three indices to distinguish fatty liver from non-fatty liver (all, p < 0.001). In men, all the three indices showed negative correlation with TFA, SFA and VFA (all, p < 0.001). The negative correlation between the three indices and VFA at the L2/3 level was higher than at L4/5 level (r = -0.476 vs. r = -0.340 for CTLP, r = -0.502 vs. r = -0.413 for LSratio, r = -0.543 vs. r = -0.422 for LSdif, p < 0.001, respectively). The negative correlation between LSratio, LSdif and VFA at L2/3 and L4/5 levels was higher than SFA at the corresponding level. In women, all the three indices showed negative correlation with VFA and TFA at L2/3 and L4/5 levels, and the negative correlation between CTLP and VFA was higher at L2/3 level than at L4/5 level (r = -0.294 vs. r = -0.254, p < 0.001). Conclusion: In non-obese Chinese adults, the degree of hepatic fatty infiltration showed a strong correlation with abdominal fat on CT. VFA at L2/3 level was more closely related to fatty liver compared with VFA at L4/5 level.

The Contact Lens Related Case Reports In Pediatric Population 2

Ai Hong Chen,Douk Hoon Kim,A Young Sung 한국안광학회 2005 한국안광학회지 Vol.10 No.3

Eye Dominance and Reading Speed

Ai-Hong Chen 한국안광학회 2011 한국안광학회지 Vol.16 No.3

Purpose: The aim of this study was to investigate eye dominance and reading performance based on eye movements and reading speed. Methods: The eye dominance of 30 subjects was determined using the sighting test (hole formed by hands). The subjects were asked to read the numerical reading material aloud in English from left to right and from right to left at random. The number of saccades, regressions, and inter-fixations per minute was calculated using Visual-Oculography (VOG) and the reading speed was recorded as number of characters per minute using stopwatch. Results: No significant differences in reading speed among right and left eye dominant subjects as they read from left to right and right to left directions (p>0.05). However, left eye dominant subjects were found to read significantly faster compared to right eye dominant subjects in both directions of reading (p<0.05). In term of eye movement patterns, no significant differences in saccades, regressions, and inter-fixations per minute were found between subjects with right eye dominance and left eye dominance for both reading directions (p>0.05). Conclusions: Reading performance in term of eye movement and speed was not affected by eye dominance, but subjects with left eye dominance read faster than subjects with right eye dominance.

On the Nature of the Gamma-ray Bursts

Hong, Kyung-Ai,Kim, Sug-Whan,Kim, Tu-Hwan 한국우주과학회 1987 Journal of Astronomy and Space Sciences Vol.4 No.2

Effect of Under and Over Refractive Correction on Visual Acuity Performance using Two Different Charts

Ai-Hong Chen,Siti Salwa Mohamad Shah,Saiful Azlan Rosli 한국안광학회 2013 한국안광학회지 Vol.18 No.3

Purpose: The purpose of this study was to investigate the effect of under and over refractive correction on visual acuity performance and the variation of the visual performance measurement using two different visual acuity charts. Methods: Ten young adults, aged between 19 and 25 years old, were recruited. Inclusion criteria: no history of ocular injury or pathology with a best-corrected visual acuity of 6/6 on dominant eye. The over and under refractive corrections were induced using minus and plus spherical ophthalmic lenses in 0.50 D steps up to 3.00 D; as well as using three axis orientations of cylindrical ophthalmic lenses (45°, 90° and 180°) in 0.50 D steps. The variation of visual acuity performance measurements was investigated using Bailey-Lovie LogMAR chart and Landolt C chart. Results: The visual acuity changes with lenses were significantly different between two charts [F = 49.15, p < 0.05 with plus spherical ophthalmic lenses and F = 174.38, p < 0.05 with minus spherical ophthalmic lenses]. The visual acuity changes with three different cylindrical axis showed no significant difference between Bailey-Lovie LogMAR chart [F = 2.35, p > 0.05] and Landolt C chart [F = 3.12, p = 0.05]. Conclusions: The over and under refractive correction affected the visual acuity performance differently. The Landolt C chart and Bailey-Lovie LogMAR chart demonstrated variation in measurements.

Comparison of Subjective Refraction Findings in Two Different Levels of Room Illumination Using Three Different Typesof Letter Charts

Ai-Hong Chen,Fatin Nur Najwa Norazman,Noor Halilah Buari,Azmir Ahmad,Wan Elhami Wan Omar 한국안광학회 2010 한국안광학회지 Vol.15 No.1

Purpose: The effect of two different levels of illumination and the effect of three letter chart types on subjective refraction findings were investigated. Methods: This study involved thirty Malay university students aged between 19 to 23 years old (7 males, 23 females), with their spherical refractive error ranged between plano to -7.75D, astigmatism ranged from plano to -1.75D, anisometropia less than 1D and with no history of ocular injury and pathology. Monocular subjective refraction was measured under two levels of illumination (with and without room light) and with three different letter charts (Snellen letter chart, wall mounted letter chart and proletter chart). Subjective refraction finding was calculated in spherical equivalent in unit diopter (D). Results: There was no significant effect in the subjective refraction findings with Snellen letter chart (t-test=p-value= 0.88), projected letter chart (t-test=-0.19, p-value=as well as wall mounted letter chart (t-test=p-value=One Way ANOVA also revealed when the subjective refractive measures were compared under two different level of room illumination (with and without room light), no significant effect of letter chart types on subjective refraction readings with room light (F2,185=p-value=and without room light (F2.185=p-value=Conclusions: Subjective refraction findings were not affected whether the room light was on or off. They were also not affected by the types of letter chart used.