• Review of KIISC
• /
• v.30 no.1
• /
• pp.55-60
• /
• 2020

2018년 1월, Meltdown, Spectre와 같은 마이크로아키텍처의 취약점을 이용하는 부채널 공격이 등장하면서 전 세계적으로 부채널 공격에 관한 관심이 증가하였다. 또한, 소모 전력 분석, 전파 분석 등 전통적 부채널 공격과는 달리 캐시의 상태변화를 이용하는 공격인 캐시 부채널 공격이 Meltdown, Spectre에 이용되면서 이에 관한 다양한 연구가 진행되고 있다. 이러한 유형의 공격은 완벽하게 방어할 수 있는 대응 패치가 존재하지 않고 일부 공격에 대응할 수 있는 대응 패치도 모든 시스템에 적용할 수 없은 경우가 많으므로 완벽한 대응이 매우 힘든 실정이다. 특히 캐시 부채널 공격을 이용하여 SGX와 같은 TEE(Trusted Execution Environment)를 공격할 수 있다는 것이 드러나면서 TEE를 공격하기 위한 다양한 공격 도구로 이용되고 있다. 본 논문에서는 Meltdown과 Spectre 및 다양한 캐시 부채널 공격에 대한 동향을 살펴보고자 한다.

• Science of Emotion and Sensibility
• /
• v.18 no.1
• /
• pp.39-48
• /
• 2015

It is known that P300-based concealed information test (P300 CIT) was not greatly affected by the traditional countermeasures. This study was to test whether P300 CIT is affected by the new countermeasures. We used three types of countermeasures. First type was a sequential countermeasure in which participants had to respond in alternating ways to irrelevants by pressing the left index finger covertly when the encountered irrelevant firstly, by wiggling the right big toe inside the shoe when encountered irrelevant secondly, by imaging his or her mother's name when encountered irrelevant thirdly, and by imaging his or her father's name when encountered irrelevant fourthly until all stimuli were presented. Second type was a partial matching and physical countermeasure. Participants in this type were asked to press the left index finger imperceptibly after one of the irrelevants and wiggle the right big toe after another of the irrelevants. Third type was a partial matching and mental countermeasure. Participants were required to imagine mother's name for one irrelevant and father's name for another irrelevant. The results showed that contrary to our expectation, the use of sequential countermeasure increased the detection rate from 77% to 92%. The partial matching countermeasure had a negative effect on P300 CIT. The physical countermeasure decreased the detection rate from 77% to 46%, and the mental countermeasure decreased the detection rate from 100% to 69%. The necessity for the development of methods to prevent or detect countermeasure is discussed.

• Journal of Korean Society of Disaster and Security
• /
• v.12 no.1
• /
• pp.35-44
• /
• 2019

In the event of a disaster (or accident), first of all, the ability to respond to an immediate disaster is important. This study investigated the disaster response capacity and the effects of disaster response exercise personnel. A questionnaire consisting of 28 items was used to assess disaster response capabilities. The questionnaire consists of contrast, preparedness initial response, warning, and response steps. Survey participants are self-service fire-fighters of small and medium-sized manufacturing companies participating in exercise. The effectiveness of the exercise. was measured by dividing the subjects before and after the exercise. Analyzing the difference between before and after exercise, it was confirmed that disaster response exercise. had significant effects on improving disaster response capacity. This study suggests that the disaster response exercise. has the effect on the disaster response capacity of the members and the necessity of disaster response exercise. As in the case study, if a company or organization regularly conducts disaster response exercise., its disaster response capabilities will improve. In addition, it is anticipated that in the event of a disaster (or accident), it will be possible to prevent or reduce property damage as well as property damage.

• The Korean Journal of Applied Statistics
• /
• v.7 no.1
• /
• pp.69-74
• /
• 1994

Kim (1992) derived influence functions of rows and columns on the eigenvalues obtained in correspondence analysis (CA) of two-way contingency tables. As in principal component analysis, the eigenvalues are of great importance in CA. The goodness of a two dimensional correspondence plot is determined by the ratio of the sum of the two largest eigenvalues to the sum of all the eigenvalues. By investigating those rows and columns with high influence, a correspondence plot may be improved. In this paper, we extend the influence functions of CA to multiple correspondence analysis (MCA), which is a CA of multi-way contigency tables. An explicit formula of the influence function is given.

• Broadcasting and Media Magazine
• /
• v.4 no.1
• /
• pp.54-61
• /
• 1999

본 논문은 ATSC표준에 대응하는 DTV수상기용 칩세트에 대해서 논한다. 1세대 칩세트는 모두 5개로, VSB복조를 위한 두 개의 칩, 트랜스포트 역다중화칩, MPEG2 MP@HL 비디오 복호화칩, 디스플레이 프로세서등으로 구성되어있다. 1세대 칩세트는 0.35/0.6$\mu\textrm{m}$ 공정으로 모든 개발이 완료되었다. 개발한 칩들의 특징, 채택한 알고리즘 및 구현시 각종 파라미터들의 최적화방법들에 대해서 설명한다. 현재 2세대 칩세트가 개발 진행 중이며 대략적인 특징 및 주요 기능을 기술한다.

• Journal of Powder Materials
• /
• v.13 no.1 s.54
• /
• pp.1-9
• /
• 2006

분말야금제품의 $90\%$를 점하는 소결기계부품의 기술동향에 대해서 주요한 재료기술과 제조기술에 초점을 두고, 고강도 혹은 고정도라고 하는 시장의 요구에 대응한 신소결재료의 개발 및 고밀도 혹은 복잡형상에 대응하는 온간성형이나 확산접합등에 관한 제조기술에 대해서 개설했다.

• Journal of Korean Ophthalmic Optics Society
• /
• v.15 no.4
• /
• pp.367-372
• /
• 2010

Purpose: The purpose of this study was to provide useful information for evaluating the sensory function of patients with strabismus by identifying the distribution of anomalous retinal correspondence (ARC) and normal retinal correspondence (NRC) by the degree of refractive errors and deviation angles. Methods: Objective refraction (AR/K, Cannon RK-F1, Japan) and subjective refraction tests were performed on 56 subjects (male: 26, female: 30) by an examiner; objective deviation angle was measured using synoptophore (OCULUS Synoptophore, Germany) with subject' eyes fully corrected for distance, and then subjective deviation angle was measured. Results: In all groups with refractive errors, the number of ARC was larger than that of NRC(67%). Particularly, it was largest in groups with myopia (71%), and in all groups, the number of UARC was larger than that of HARC. In groups with anisometropia, although the numbers of NRC and ARC were same, the number of UARC was larger than that of HARC as in other groups. In the distribution of NRC and ARC by deviation angle, the number of NRC was larger than that of ARC (46%) only at microstrabismus (0 ~ ${\pm}10{\triangle}$). Conclusions: Normal retinal correspondence were the most emmetropia in the retinal response were much higher than in the more hyperopia than the retinal correspondence were more myopia. In addition, the smaller the angle of retinal correspondence Normal over many, but overall, respectively.

• Proceedings of the Korea Contents Association Conference
• /
• 2014.11a
• /
• pp.471-472
• /
• 2014

무기-표적할당(Weapon-Target Allocation: WTA)은 방어 무기체계의 신속하고 정확한 교전결심을 지원하기 위한 핵심적인 기술로서, 다수의 표적이 아군을 위협하는 상황에서 다수의 표적을 효과적으로 요격할 수 있도록 제한적인 무기자산을 효율적으로 할당하는 최적의 해를 찾는 문제이다. 최적의 해에 대한 평가 기준은 무기-표적 쌍들에 대한 요격확률의 합으로 계산된다. 요격확률은 무기가 표적을 요격하는 시점에 따라서 달라지므로, 정밀한 교전결심을 위해서는 요격 시점을 고려하여 무기를 할당하는 것이 중요하다. 특히나 초고속표적을 대응할 때는 표적의 속도가 매우 빨라 요격할 수 있는 시간이 매우 짧기 때문에 더욱 중요하다. 이러한 요구사항에도 불구하고 기존 연구에서는 요격 시점을 고려한 무기할당에 대한 연구가 미진하였다. 본 논문에서는 요격 시점을 고려한 무기할당 알고리즘을 제안하고자 하며 알고리즘에 대한 성능으로 표적에 대한 요격률뿐만 아니라, 표적 출현부터 요격까지의 소요시간인 교전반응시간을 분석하여 신속대응에 대한 성능도 함께 제시한다.

• The Journal of the Korea Contents Association
• /
• v.16 no.6
• /
• pp.529-536
• /
• 2016

The purpose of this research is to evaluate the quality of Differential Police Response strategy. Although it has been approximately three years since these new police response systems were introduced, there is no research to evaluate them empirically. Using two types of statistical quality control techniques, Xbar-R control charts for variables data and P charts for attributes data, this study analyzes approximately 3,000 calls reported throughout the year 2012 to the 112 Integrated Dispatch Center in Ik-san police station. The Xbar-R control charts revealed that the police did not consistently respond to an emergency call for service (i.e., code one case) within 3 minutes. The P control chart also identified that there was a significant variation in the portion/number of defective calls where police failed to respond to non-emergency calls for service within 5 minutes. The results from this study suggest the police may need to review the target response time for code 1 and code 2 respectively.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.23 no.1
• /
• pp.69-79
• /
• 2013

Recently, many enterprises are suffering from advanced types of malware and their variants including intelligent malware that can evade the current security systems. This addresses the fact that current security systems have limits on protecting advanced and intelligent security threats. To enhance the overall level of security, first of all, it needs to increase detection ratio of each security solution within a security system. In addition, it is also necessary to implement internetworking between multiple security solutions to increase detection ratio and response speed. In this paper, we suggest a collaborative security response method to overcome the limitations of the previous Internet service security solutions. The proposed method can show an enhanced result to respond to intelligent security threats.