• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.561-563
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• 2014

애드혹 네트워크(Ad Hoc Network)는 최근 이슈가 되고 있는 사물 간 인터넷(Internet of Things), 스마트그리드(Smart Grid), 사람 중심 도시 센싱(People-Centric Urban Sensing), 해상 통신(Maritime Communications) 환경에서 다양하게 활용되는 네트워크 구조다. 이러한 환경에서의 애플리케이션들은 사용자들에게 다양한 편의성을 제공하기 위하여 사용자의 민감한 프라이버시 정보를 요구하기도 한다. 하지만, 만약 수집되어지는 프라이버시 정보가 인가되지 않은 공격자에게 노출된다면, 사용자는 불안함을 호소할 수 있을 것이고, 동시에 해당 데이터를 수집하고자 했던 서비스제공자는 경제적으로 커다란 손실을 입을 수 있다. 이러한 프라이버시 정보 노출을 방지하기 위하여 안전한 데이터 수집 기법들이 연구되어 왔다. 하지만, 대부분의 기법들은 기밀성만 제공할 뿐, 부인방지 및 익명성은 제공하지 않는다. 그리고 더 나아가 기존 기법들은 통계정보 수집과 개별적인 정보 수집을 동시에 제공하지 않는다. 본 논문은 개별정보수집 및 통계정보 수집을 모두 지원하며 동시에, 사용자에게 강화된 익명성 개념인 비연결성을 제공하는 새로운 데이터 수집 기법을 소개한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.603-610
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• 1997

냉전 종식 후에도 동북아시아지역의 불안정 상황은 여전히 지속되고 있다 특히 핵군비와 관련하여 역내 각 국의 동향은 매우 민감한 상태이다. 이런 면에서 이 지역의 비핵지대화는 이 지역의 불안요인에 대한 안전보장 장치가 될 수 있다. 이해 당사국들이 대체로 소극적인 태도를 보이고 있기는 하나, 객관적 상황은 비핵지대화 논의에 유리하다. 논의를 본격화하기 위해서는 첫째, 핵보유국들의 비보유국들에 대한 소극적 안보 약속, 둘째, 핵보유국 상호간의 핵 선제 불사용 합의, 셋째, 핵보유국의 핵감축 의지 표명, 넷째, 일본의 핵투명성 제고 등의 충족이 요구된다. 현재까지 논의되고 있는 구상들로는 북한 핵문제에 대한 우려가 한창 고조되던 당시에 거론되었던 한반도 비핵지대화안, 동북아 비핵지대화안, 제한적 비핵지대화안 등이 있다. 5개 핵보유국들의 협조가 없는 한 비핵지대의 실현은 어렵다. 또한 역내에 3개 핵보유국을 가지고 있는 동북아 지역의 특성에 비춰 비핵지대화의 효과를 높이기 위해서는 첫째, 집단안보라는 보다 큰 틀을 전제로 하는 접근이 필요하며, 둘째, 핵보유국들의 거부반응을 괴려한 점진적 방식의 채택이 요구된다. 그러나 무엇보다도 역내 국가들 간의 신뢰 조성 및 평화와 안정의 증진이 우선해야 하며, 그 후 지역국가들 스스로의 주도로 논의를 이끌어 나가야 할 것이다.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.945-947
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• 2011

클라우드 컴퓨팅 인프라를 사용할 때 사용자의 민감한 정보가 포함된 데이터를 사용하게 될 수 있다. 데이터를 아웃소싱하여 처리하는 경우 클라우드 제공자가 데이터 처리자로서 사용자의 데이터에 접근해야 한다. 사용자는 데이터를 처리하는 과정에서 행하는 클라우드 제공자의 동작을 알 수 없으므로 클라우드 컴퓨팅을 사용하는 것을 불안해하게 되고 공개를 해도 되는 일부의 데이터만을 사용하게 된다. 본 연구에서는 클라우드 컴퓨팅을 통해 연산을 수행하는 환경에서 사용자의 데이터를 보호하기 위한 연구의 일환으로써, 시스템 및 환경을 정의하고 주로 발생할 수 있는 정보보호 위협을 정리하였다. 또한 현재 연구가 진행되고 있는 SMPC(Secure Multi-Party Computation)을 소개하고 이를 클라우드 컴퓨팅을 통해 연산을 수행하는 환경에 적용하기 위해 고려해야 할 사항들을 제시하며, 향후 연구 방향을 모색한다.

• Sleep Medicine and Psychophysiology
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• v.30 no.1
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• pp.22-27
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• 2023

Objectives: The purpose of this study was to develop a screening tool that is simple and easy to use for assessing sleep problems, including hypersomnolence, restless legs syndrome, and insomnia. We also examined the reliability and validity of this tool. Methods: We developed the Sleep Problem Screening Questionnaire (SPSQ), which consists of three sub-sections: insomnia (SPSQi), hypersomnolence (SPSQh), and restless legs syndrome (SPSQr). Subsequently, the participants, consisting of 222 patients with insomnia disorder and 78 healthy individuals, completed both the SPSQ and the comparative scale (Korean version of the Insomnia Severity Index). The analysis was then conducted using this data. Results: The SPSQ demonstrated good convergent and discriminant validity, as well as satisfactory internal consistency. A cutoff score of 6 on the SPSQi was found to be optimal for distinguishing individuals with insomnia. Conclusion: The results of this study suggest that the SPSQ is a reliable and valid tool for screening sleep problems among general adult population. However, there is a limitation as a comparison and validation with scales related to restless legs syndrome and hypersomnolence were not conducted.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.4
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• pp.263-270
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• 2012

Ascorbic acid (Vitamin C) becomes unstable in the aqueous phase by oxygen, light and alkali, etc. The properties are limited in application to cosmetics. The most important factor that determines the destabilization of ascorbic acid in the aqueous phase was tried to understand considering its molecular deformation and degradation. In this study, we changed the polyols and emulsification technique for the stability of ascorbic acid. Then we observed the color and concentration change of ascorbic acid at room temperature and high temperature ($42^{\circ}C$) for 6 weeks and identified the stability using HPLC regularly. As a result, we found that glycerin was the most appropriate polyol for stability of the ascorbic acid. Also the technique of nonaqueous emulsification stabilized ascorbic acid than P/S emulsification. Also, P/S emulsification, glycerin was more stable than propylene glycol. By the results we suggest that ascorbic acid could be stabilized by nonaqueous emulsification method and this data could be applied to stabilization methods for cosmetic products.

• Korean Journal of Cognitive Science
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• v.20 no.3
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• pp.357-381
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• 2009

Although it is known that there are personality characteristic variances in the sensitivity to environmental feedback, the trait individual difference has scarcely been explored in the context of recognition memory decision. The present study investigated this issue by examining the relationship between the feedback-based adaptive flexibility of recognition criterion positioning and personality differences in general sensitivity to non-laboratory outcomes. Experiment 1 demonstrated that veridical feedback itself had little effect on the recognition decision criterion whereas Experiment 2 demonstrated that biased feedback manipulations selectively restricted to high confidence errors, induced shifts even in the overall Old/New category criterion. Critically, individual differences in stable personality characteristic linked to reward seeking(Behavioral Activation System-BAS) and anxiety avoidance (Behavioral Inhibition System-BIS) has been shown to predict the sensitivity of subjects to this form of feedback-induced criterion learning. This data further support the idea that incremental reinforcement-based learning mechanism not often considered important during explicit recognition decisions may play a key role in criterion setting.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.345-352
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• 2017

In this study, squeal noise with respect to pressure variation is measured by a lab-scaled brake dynamometer and estimated by a complex finite element (FE) eigenvalue analysis. From the FE eigenvalue sensitivity analysis, unstable frequencies occur due to a mode-coupling mechanism and are found to change with variation in contact stiffness. In the experiment, squeal frequencies near 1 kHz, 2.5 kHz, 3.5 kHz, and 4 kHz are increased with pressure variation. The sensitivity of squeal modes to contact stiffness variation obtained from the FE analysis is shown to approximate the variation of squeal frequencies under pressure variation in the experiment.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.79-87
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• 2002

Acoustic responses to pressure oscillations in axisymmetric combustion chamber are numerically investigated to examine the qualitative trend of acoustic instability in liquid rocket engine. Chamber operating condition and excitation frequency of oscillating pressure are selected as exciting parameters of acoustic instability. Artificial perturbation is simulated by total-pressure oscillation with sine wave at chamber inlet. Many approximations and simplifications are introduced without losing the essence of acoustic pressure response. First, steady-state solution for each operating condition is obtained and next, transient analysis is conducted. Depending on operating condition and excitation frequency, the distinct response characteristics are brought. Weak-strength flames and high-frequency excitation tend to cause sensitive acoustic pressure response leading to unstable pressure field. These results are analyzed based on the correlation with acoustic pressure responses from the previous works adopting laminar flamelet model.

• The Korean Journal of Franchise Management
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• v.2 no.2
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• pp.95-110
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• 2011

As global economic conditions are getting uneasy and polarization of our economy is intensified, the economic sentiment of small businesses is still low and unstable. The collapse of worldwide banking systems due to sub prime crisis in 2007 became the catalyst that shakes financial industries in each country in the world; the most sentiment people, small businesspersons, also have hard time facing survival way out, facing a great crisis. All organizing powers including manufactures, wholesales and retails are being gradually greater in mutual relations and dependence, and unstable factors about risks are also increasing. For exterior environmental and physical risk factors which cannot make small businesses survive themselves by developing ways out are eventually increasing, those who cannot cope with these factors face a great crisis. Although the government tries hard to overcome this situation conducting many ways, the effect does not continue. It is the real state that independent business markets including overall employment and establishing business have vicious cycle that they cannot be improved, due to increase of employment centered on short-term labors which lack durability in creation of employment and decline of household income. Recently, growth shows indication of slowdown because of multinational risk factors including financial crisis in each country in Europe, the death of Kim Jung-il, relationship with North Korea, and unstability of war situation in the Middle East Asia. Experts expect that growth rate will be about 4%, and independent business that ordinary people feel is still gloomy. It's reality that there is no adequate alternative for lack of jobs, unstable employment and a means of living after retirement. Also, the fact that large companies enter the market which is narrow and in the excessive competition should be an environmental factor that makes the situation worse. The business concept, a franchise, is the part we should think about whether it is the institutional solution that can guarantee independent businessmen stable life. Major companies are frightfully entering the market today, breaking the barrier to entry and shouting of a win-win with independent businesses. It's the small businesspersons who go through painful domestic recession, cannot predict the future and manage confusing and unstable independent business. It's very important to restore the domestic economy through wisely boosting consumption as soon as possible. It's also important to lead the situation by gathering powers of the government and related organizations, agonizing, suggesting solutions, and establishing accurate directions. The purpose of this study, therefore, is to suggest ways to strengthen competitiveness of small businesspersons by examining small business support policies which are currently implemented.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.1
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• pp.51-59
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• 2000

This study aims to reveal whether attachment relationship with parents can differ from children being accepted and rejected in peer relations, and whether children's rejection sensitivity can differ from children having secure and insecure attachment relationship with parents. Subjects were 218 students in fifth and sixth grade of primary school. Inventory of Parent and Peer Attachment(IPPA), Children's Rejection Sensitivity Questionnaire(CRSQ), and peer relation sociometrics were used as measurements. The results showed that children in secure attachment with parents had lower scores on the subscales of CRSQ, such as anxiety, anger, belief, and psychological reaction, than children in insure attachment relationship with parents. And IPPA scores were higher in children being accepted in peer relation than children being rejected. These results can be considered that early attachment relationship with parents may influence children's rejection sensitivity and peer relation.