• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.78-78
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• 2003

Embryonic stem (ES) cells, derived from preimplantation embryo, are able to differentiate into various types of cells consisting the whole body, or pluripotency. In contrast, terminally differentiated cells do not usually alter their nature but frequently die or transform if they are exposed to inappropriate external stimulations. In addition to the plasticity, ES cells are expected to be different from terminally differentiated cells in very many ways, such as patterns of gene expressions, ability and response of the cells in confronting environmental stimulations, metabolism, and growth rate. As a model system to differentiate these two types of cells, human ES cells (MB03) and terminally differentiated cells (HeLa), we examined the ability of these two types of cells in confronting a severe oxidative insult, that is $H_2O$$_2$. Approximately 1$\times$10$^4$ cells were plated in 96 well plate and serum starved for overnight. The conditioned cells were exposed to a various concentration of $H_2O$$_2$ fur 24 hrs and loaded with neutral red (50$\mu\textrm{g}$/ml) for 4 hrs, washed with PBS for 2 min three times, and entrapped dye was dissolved out using acetic ethanol. Cytotoxicity was determined by reading the amount of dye in the medium using microplate reader. equipped with 575 nm filter. Relative amount of the dye entrapped within MB03 or HeLa were not significantly different when cells were exposed up to 0.4 mM $H_2O$$_2$. However, this sharply decreased down to 0.12% in HeLa cells when the cells were exposed to 0.8 mM $H_2O$$_2$, while it was approximately 54% in MB03 suggesting that this concentration of $H_2O$$_2$ is the defensive threshold for HeLa cells. The resistance to oxidative stimulation reversed, however, when cells were co-treated with BSO (L-buthionine- 〔S, R〕-sulfoximine) which chelates intracellular GSH. This result suggests that cellular GSH is the major defensive mechanism of human ES cells. Induction of enzymes involved in GSH metabolism and type of cell death is currently being studied.

• Journal of Oriental Neuropsychiatry
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• v.19 no.3
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• pp.23-34
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• 2008

Objective: The purpose of this study was to investigate characteristics of the defense mechanism of oriental medicine students by using Ewha Defense Mechanism Test(EDMT) preliminarily. Method: We described the characteristics of the defense mechanism of oriental medicine students and compared the scores of EDMT with standard group. We analysed the differences of defense mechanism by sex (male, female) and age($\leq$29 and $\geq$30 yrs old) within oriental medicine students. The score of EDMT were verified by examination of one sample t-test and unpaired t-test. Results and Conclusions: First, there was no Major Defense Mechanism in oriental medicine students. Second, oriental medicine students had more defensive, passive inclination and used Evasion and Show-off more frequently. Third, the differences within oriental medicine students depended on age rather than sex. The younger students used immature and neurotic defense mechanisms more frequently, and the older students had more defensive and passive inclination.

• ETRI Journal
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• v.41 no.5
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• pp.585-598
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• 2019

A cyber-physical system (CPS) is a new mechanism controlled or monitored by computer algorithms that intertwine physical and software components. Advanced persistent threats (APTs) represent stealthy, powerful, and well-funded attacks against CPSs; they integrate physical processes and have recently become an active research area. Existing offensive and defensive processes for APTs in CPSs are usually modeled by incomplete information game theory. However, honeypots, which are effective security vulnerability defense mechanisms, have not been widely adopted or modeled for defense against APT attacks in CPSs. In this study, a honeypot game-theoretical model considering both low- and high-interaction modes is used to investigate the offensive and defensive interactions, so that defensive strategies against APTs can be optimized. In this model, human analysis and honeypot allocation costs are introduced as limited resources. We prove the existence of Bayesian Nash equilibrium strategies and obtain the optimal defensive strategy under limited resources. Finally, numerical simulations demonstrate that the proposed method is effective in obtaining the optimal defensive effect.

• Journal of Oriental Neuropsychiatry
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• v.20 no.3
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• pp.189-203
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• 2009

Objectives : This study was to analyze characteristics of MMPI profile, personality and defensive mechanism on 32 Hwa-byeng patients. Methods : 32 Hwa-byeng patients and 28 normal control group were administered the MMPI. The characteristics of MMPI profile and the clinical scales of personality and defensive mechanism were analyzed statistically. Results : 1. Half of female Hwa-byeng patients are in their forties, twelve patients are high school graduates, housewives seem to have Hwa-byeng more than workers, and married ones have Hwa-byeng more than singles, divorcees or separated one 2. 60.6% patients are getting stressed from their husbands(the specific reasons are infidelity(55%), incapability(25%) and violence(20%)). And the rest are from in-law(28.8%), children(6.4%) and their own parents(3.2%). 3. MMPI profile of Hwa-byeng patients appeared as a type of 3-1 elevated by the scale of 3(Hy) and 1 (Hs). And Hwa-byeng patients appeared significantly high in the rest of scales except L, K, Mf and Ma scales comparing to control group. 4. Hwa-byeng patients were classified into 3 groups. First group is "V" type which is high in K scale and low in 3 (Hy), 4(Pd), 6(Pa). Second group is "V" type which is high in K scale and high in 3(Hy), 4(Pd), 6(Pa). Third group is high in F scale and high in 1(Hs), Z(D), 3(Hy), 4(Pd), 6(Pa), 7(Pt), 8(Sc) and 0(Si). 5. The analysis on MMPI profiles indicates that the thirties are highier in F scale than the fifties, the fifties are highier in Hy scale than the forties, workers are highier in Pd scale than housewives, singles or divorcees are highier in Pa scale than the married. 6. The characteristics of personality in Hwa-byeng patients are as follows. They are significantly lower in HST, NAR and very higher in CPS, PAG, DEP, STY, AVD, SZD comparing to control group. Especially in AVD and SZD scales are appeared the highest.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.214.2-215
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• 2003

Reactive oxygen species play an important role in aging. carcinogenesis, and certain neurological disorders of human beings in addition to the host-defensive mechanism of inflammatory response. Murine macrophages Raw264.7 released superoxide anions via NADPH oxidase complex and nitric oxide (NO) via iNOS synthase when the cells were stimulated with unopsonized zymosan binding to complement receptor. (omitted)

• Journal of Communications and Networks
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• v.18 no.6
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• pp.948-961
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• 2016

Internet protocol (IP) spoofing is a serious problem on the Internet. It is an attractive technique for adversaries who wish to amplify their network attacks and retain anonymity. Many approaches have been proposed to prevent IP spoofing attacks; however, they do not address a significant deployment issue, i.e., filtering inefficiency caused by a lack of deployment incentives for adopters. To defeat attacks effectively, one mechanism must be widely deployed on the network; however, the majority of the anti-spoofing mechanisms are unsuitable to solve the deployment issue by themselves. Each mechanism can work separately; however, their defensive power is considerably weak when insufficiently deployed. If we coordinate partially deployed mechanisms such that they work together, they demonstrate considerably superior performance by creating a synergy effect that overcomes their limited deployment. Therefore, we propose a universal anti-spoofing (UAS) mechanism that incorporates existing mechanisms to thwart IP spoofing attacks. In the proposed mechanism, intermediate routers utilize any existing anti-spoofing mechanism that can ascertain if a packet is spoofed and records this decision in the packet header. The edge routers of a victim network can estimate the forgery of a packet based on this information sent by the upstream routers. The results of experiments conducted with real Internet topologies indicate that UAS reduces false alarms up to 84.5% compared to the case where each mechanism operates individually.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.97-97
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• 2003

Embryonic stem (ES) cells, derived from preimplantation embryos, are able to differentiate into various types of cells consisting the whole body, or pluripotency. In addition to the plasticity, ES cells are expected to be different from terminally differentiated cells in very many ways, such as patterns of gene expressions, ability and response of the cells in confronting environmental stimulations, metabolism, and growth rate. As a model system to differentiate these two types of cells, human ES (hES, MB03) cells and terminally differentiated cells (HeLa), we examined the ability of these two types of cells in confronting a severe oxidative insult, that is $H_2 O_2$. Ratio of dying cells as determined by the relative amount of dye neutral red entrapped within the cells after the exposures. Cell death rates were not significantly different when either MB03 or HeLa were exposed up to 0.4 mM $H_2 O_2$. However, relative amount of dye entrapped within the cells sharply decreased down to 0.12% in HeLa cells when the cells were exposed to 0.8 mM $H_2 O_2$, while it was approximately 54% in MB03. Pretreatment of cells with BSO (GSH chelator) and measurement of GSH content results suggest that cellular GSH is the major defensive mechanism of hES cells. Induction of apoptosis in hES cell was confirmed by DNA laddering, induction of Bax, and chromatin condensation. In summary, hES cells 1) are extremely resistant to oxidative stress, 2) utilize GSH as a major defensive mechanism. and 3) experience apoptosis upon exposure to oxidative stress.

• Journal of Families and Better Life
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• v.26 no.1
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• pp.31-49
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• 2008

This study has been performed to explore verbal and behavioral expression of sexual desires among male elderly residents who have been living in long tenn care facilities. There are three topics covered in this study; first, in what situations and how seriously do care workers encounter expression of sexual desires of the elderly residents? Second, what kind of negative consequences do they believe those sexual behaviors will lead to? Third, how can we implement defensive measures against the sexual behaviors? In this study, twenty three care workers working full time in five retirement and care facilities were asked about their experience and perception of the above study agendas, and answers of the qualitative interview were drawn as follow; first, the elderly residents apparently show a variety of sexual harassment and provoking behaviors such as sticking to specific women, physically touching and attacking, and induce obscenely activities against female residents, care workers, and volunteer visitors. Second, their sexual behaviors are often influenced by their isolated and abandoned emotionality as well as living situation in rural areas. Third, their sexual behaviors often critically affect care work plan and facility managements by severely discouraging female care givers and community supporters. Therefore in this study, suggestions and defensive measures were made as follows: first, education and counselling programs toward female workers and volunteers need to be developed, and the programs should cover psychological and behavioral mechanism of sexuality in later life. Second, self control plans need to be empowered toward the elderly residents; in the plans, the elderly residents shall be encouraged to evaluate primary cause and proper solutions of sexual behaviors of their peering residents. Third, combination of healthy housing and care facilities for frail elderly need to be integrated in a neighboring location, so that when residents and workers encounter extreme episodes of sexuality of healthy residents in a housing facility, the problematic sexual residents are partially transferred into a neighboring care facility and thereafter other residents and cafe givers are relieved from stressful contacts with the extremely sexual residents.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.8B
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• pp.947-953
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• 2011

These days, a consistent and fatal attack attribute toward a database has proportionally evolved in the similar development form to that of security policy. Because of access control-based defensive techniques regarding information created in closed networks and attacks on a limited access pathway, cases of infringement of many systems and databases based on accumulated and learned attack patterns from the past are increasing. Therefore, the paper aims to separate attack information by its types based on a virtual infringement pattern system loaded with dualistic VM in order to ensure stability to limited certification and authority to access, to propose a system that blocks infringement through the intensive management of infringement pattern concerning attack networks, and to improve the mechanism for implementing a test that defends the final database, the optimal defensive techniques, and the security policies, through research.

• Strategy21
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• s.44
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• pp.142-176
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• 2018

So far, the main threat to South Korea was North Korea. That is why South Korea established a strategy based on the threat of North Korea and most of the budget on defense was used to deter North Korea. Even though the neighboring countries(China, Japan, and Russia) are growing as a real threat with abilities and intentions based on their powerful naval forces, South Korea has not yet been able to establish a strategy that regards neighboring countries as a threat. But the decades-old structural mechanism of the Korean security environment is undergoing a radical change on April 27, 2018, through the South-North summit and the Panmunjom Declaration. Under the changing security environment, South Korea was placed in a complicated dilemma that had to deal with threats of two axes(China), three axes(China, Japan), and four axes(Japan, Russia). If the one axis threat(North Korea) is dominated by land threats, the second, third and fourth axis threats are threats from the sea. This paper analyzed the maritime strategy of Korea within the framework of maritime-geopolitics, in other words recognition and expansion of the sphere of maritime. I have designed that the maritime defense space that we can deny from threats is divided into three lines of defense: 1 line (radius 3,000km), 2 lines (2,000km), and 3 lines (1,000km). The three defense zones of the three lines were defined as an active defense(1 line), defensive offense(2 line), active offense(3 line). The three defense zones of the three lines were defined as the sphere of core maritime, As a power to deny the sphere of core maritime, it was analyzed as a maneuvering unit, a nuclear-powered submarine, the establishment of missile strategy, and the fortification of islands station. The marine strategy of South Korea with these concepts and means was defined as 'Offensive Maritime Denial Strategy'.