• Biomedical Science Letters
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• v.15 no.2
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• pp.153-160
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• 2009

Photodynamic therapy(PDT) is a treatment utilizing the generation of singlet oxygen and other reactive oxygen species(ROS), which selectively accumulate in target cells. The aim of present work is to investigate the photodynamic therapy mechanism of 9-HpbD-a-mediated PDT in HeLa cell lines. We studied the general reactive oxygen species(G-ROS) activation after 9-HpbD-a PDT using fluorescence stain with $H_2DCF-DA$. G-ROS activation observed after 9-HpbD-a PDT and higher activation condition was 1 hour after PDT at 0.5 ${\mu}g/ml$ 9-HpbD-a concentration. Sodium azide and reduced glutathione(the singlet oxygen quencher) could protect HeLa cells from cell death induced by 9-HpbD-a PDT. But D-mannitol(the hydroxyl radical scavenger) could not protect cell death. Singlet oxygen played a decisive role in 9-HpbD-a PDT induced HeLa cell death. Type II reaction was the main type of ROS formation at 9-HpbD-a PDT.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.992-997
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• 2007

Cisplatin is a chemotherapeutic drug which is widely used for cancer therapy including cervical cancer. The purpose of this study is to elucidate synergistic effect of Cisplatin and Berberine on the apoptosis of HeLa cells and to determine whether oxidants are formed as part of apoptotic process. Apoptotic death of HeLa cells by cisplatin and berberine was confirmed by chromatin condensation of HeLa cells and flow cytometric analysis of intracellular ROS(reactive oxygen species) production. In MTT assay, Cell viability was decreased and enhanced ROS generation in combination of cisplatin and berberine significantly, as compared with cisplatin only. Synergistic effect of Cisplatin and Berberine on the inhibition of cell growth by apoptosis was clearly observed and ROS may play an important role in apoptosis. This effect suggest the possibility lowering the concentration of chemotherapeutic drugs, which alleviate the side effect of drugs.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.442-445
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• 1997

A challenging activity in the manufacturing industry is to perform in real time the continuous monitoring of the process state, the situation assessment and identification of the problem on line and diagnosis of the cause and importance of the problem if he process does not work properly. This paper describes LAT(Ladder Analysis Tool) system for fault tree generation to improving the fault diagnosis of CNC machine tools. The system consists of 4 steps which can automatically ladder analysis from ladder diagram to two diagnosis function models. The two diagnostic models based on he ladder diagram is switching function model and step switching function model. This system tries to overcome diagnosis deficiencies present machine tool.

• Journal of Families and Better Life
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• v.26 no.3
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• pp.149-168
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• 2008

The objective of this study was to expand understanding of children's exposure to domestic violence in Korean society. In-depth personal interview was conducted by a researcher on individual experience of domestic violence in childhood. The findings of this qualitative study are summarized as follows; 1) A person who experienced domestic violence in childhood is likely to feel powerless, and think of himself/herself worthless. 2) He/She needs to have sufficient social support and protective networks. 3) A person who experienced parental violence in childhood is to suffer from people's negative behaviors such as social prejudice, preconception, and discrimination. 4) He/She is worried about the cycle of violence from generation to generation. 5) It is necessary for him/her to overcome his/her negative emotions acquired by the experience of domestic violence in childhood to have a constructive goal for the future.

• Journal of the Korean Society of Combustion
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• v.19 no.4
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• pp.28-34
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• 2014

Numerical study is conducted to grasp flame characteristics in $H_2/CO$ syngas counterflow diffusion flames diluted with He and Ar. An effective fuel Lewis number, applicable to premixed burning regime and even to moderately-stretched diffusion flames, is suggested through the comparison among fuel Lewis number, effective Lewis number, and effective fuel Lewis number. Flame characteristics with and without the suppression of the diffusivities of H, $H_2$, and He are compared in order to clarify the important role of preferential diffusion effects through them. It is found that the scarcity of H and He in reaction zone increases flame temperature whereas that of $H_2$ deteriorates flame temperature. Impact of preferential diffusion of H, $H_2$, and He in flame characteristics is also addressed to reaction pathways for the purpose of displaying chemical effects.

• The Journal of Korean Medical History
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• v.19 no.1
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• pp.99-110
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• 2006

Lee Heon gil (a.k.a. Mongsoo), who was the pioneer of measles treatment in the 18th century, is the 14th generation of the Deokcheongun branch of the Lee family from Jeonju, living from August 25, 1738 (14th year of King Yeongjo) to April 29, 1784 (8th year of King Jeongjo). Under his teacher Lee Cheol hwan, the eldest grandson of Lee Yik, he learned medicine and studied it deeply. His medical service was most remarkable when measles was prevalent in 1775 (51st year of King Yeongjo) at his age of 38. It seems that he wrote books on measles based on his experiences at that time. Lee Heon gil's academic background can be inferred from his relation with Lee Cheol hwan and Jeong Yak yong. Associating with Lee Cheol hwan, he established close relationships with many scholars including the Lee family from Yeoju, who were the descendents of Seongho Lee Yik, and through this fellowship he was influenced directly and indirectly by Seongho Lee Yik. In addition, he maintained close contact with Jeong Yak yong while treating him several times. As Jeong Yak yong was also in close academic association with scholars in the Seongho School and Lee Yik's pupils, he had a philosophical consensus with Lee Heon gil. These academic backgrounds show that the philosophical flow of the Seongho School from Seongho Lee Yik to Jeong Yak yong also reached Lee Heongil.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.622-627
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• 1994

Conducting solid samples are successfully analyzed with the spark ablation combined to the moderate power (500W) Helium Microwave Induced Plasma (He MIP). The relative standard deviations are in the range of 3-10% and the detection limits are around 50 ${\mu}$g $g^-1$. These values are higher than those of Ar MIP or Ar Inductively Coupled Plasma. Spark ablated particles are examined to investigate the analytical characteristics of the system.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.1
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• pp.75-86
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• 2014

Demand for the femtocell is largely credited to the surge in a more always best connected communication conscious public. 3GPP defines new architecture and security requirement for Release 9 to deal with femtocell, Home eNode B referred as HeNB. In this paper, we analyze the HeNB security with respect to mutual authentication, access control, and secure key agreement. Our analysis pointed out that a number of security vulnerabilities have still not been addressed and solved by 3GPP technical specification. These include eavesdropping, man-in-the-middle attack, compromising subscriber access list, and masquerading as valid HeNB. To the best of our knowledge, any related research studying HeNB security was not published before. Towards this end, this paper proposes an improved authentication and key agreement mechanism for HeNB which adopts proxy-signature and proxy-signed proxy-signature. Through our elaborate analysis, we conclude that the proposed not only prevents the various security threats but also accomplishes minimum distance from use-tolerable authentication delay.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.8
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• pp.301-312
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• 2018

This The main objective of the study is to examine success clues of the firm influenced by top manager(Masayoshi Sohn) who belongs to Korean-Japanese third generation diaspora. A company's management style depends greatly on the value of its top manager, who also affects success and failure of the firm. SOFTBANK's management style could be influenced by the identity and values of Masayoshi Sohn. The results of the study are as follows ; firstly, his firm remains born-global firm owing to his global value rooted from his de-ethnification and studying in America. Secondly, the firm has challenge spirit owing to his experience of overcoming discrimination and repression during childhood time. and his role model 'Ryoma". Thirdly, there is a roly poly spirit in his firm because he has overcome complex coming from Korean-Japanese third generation diaspora. Finally, his company has human-oriented management philosophy because he has influenced a lot form his grand mother, Won-Cho Lee who emphasized much on human-beings. His identity and values have infiltrated Softbank's management style, which has led to the success of the company. This study will provide you with different viewpoints on the study for Korean-Japanese third generation diaspora. Especially, this study can be meaningful in which it is a study on the third generation of Korean-Japanese diaspora and the global corporations he is running since there are few such studies up to now.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.6
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• pp.340-346
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• 2003

This paper presents a game theory application for an analysis of uniform price auction in a simplified competitive electricity market and analyzes the properties of Nash equilibrium for various conditions. We have assumed that each generation firm submits his bid to a market in the form of a sealed bid and the market is operated as a uniform price auction. Two firms are supposed to be the players of the market, and we consider the maximum generation quantity constraint of one firm only. The system demand is assumed to have a linear relationship with market clearing prices and the bidding curve of each firm, representing the price at which he has a willingness to sell his generation quantity, is also assumed to have a linear function. In this paper, we analyze the effects of maximum generation quantity constraints on the Nash equilibrium of the uniform price auction. A simple numerical example with two generation firms is demonstrated to show the basic idea of the proposed methodology.