• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.11a
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• pp.281-282
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• 2004

• Journal of Life Science
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• v.22 no.6
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• pp.760-771
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• 2012

Marine triterpene glycosides are physiologically active natural compounds isolated from sea cucumbers(holothurians). It was demonstrated that they have a wide range of biological activities, including antifungal, cytotoxic, and antitumor effects. A previous study showed that stichoposide C (STC) isolated from Thelenota anax induces apoptosis through generation of ceramide by activation of acid sphingomyelinase (SMase) and neutral SMase in human leukemia cells. In this study, we investigated whether STD, a structural analog of STC, can induce apoptosis and examined the molecular mechanisms for its activity. It was found that STC and STD induce apoptosis in a dose- and time-dependent manner and lead to the activation of caspase-8, mitochondrial damage, activation of caspase-9, and activation of caspase-3 in K562 and HL-60 cells. STC activates acid SMase and neutral SMase, which results in the generation of ceramide. Specific inhibition of acid SMase or neutral SMase partially blocked STC-induced apoptosis, but not STD-induced apoptosis. In contrast, STD generates ceramide through the activation of ceramide synthase. Specific inhibition of ceramide synthase partially blocked STD-induced apoptosis, but not STC-induced apoptosis. Moreover, STC and STD markedly reduced tumor growth of HL-60 xenograft tumors and increased ceramide generation in vivo. These results indicate that STC and STD can induce apoptosis and have antitumor activity through the different molecular mechanisms, because they have a different sugar residue attached to aglycones. Thus, these results suggest that their actions are affected by a sugar residue attached to aglycones and they can be used as anticancer agents in the treatment of leukemia.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.8
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• pp.617-628
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• 1989

In systematic tuning of digital STC parameters, systems with time-varying parameters and systems with time-varying delays are studied individually because of many preconditions and difficulties. In order to eliminate all these difficulties effectively, the expert control technique is required to enhance STC control functions. In this paper, an expert controller, a STC utilizing expert control technique, for process control is designed. The expert controller is composed of an unstability indicator for detecting plant unstability, an expert back-up controller and an expert STC which are switched each other by the unstability indication, and expert system with knowledge base and inference engine. This expert controller is able to perform control functions successfuly for the following` 1) a system which has unknown and time-varying delay time, 2) a time-varying system which has unknown parameters, and 3) a system with minimun and non-minimum phase. The robust control function is demonstrated by computer simulations.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.31-34
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• 2005

The article is devoted to the study of some hi-and tricyclic derivatives of aziridine as materials lot newindicators of ionizing radiation. To create high sensitive materials some aspects of photo induced ring opening processes in aziridine derivatives in ethanol solutions and in polymeric matrix were studied and two steps character of the processes investigated was established. Two types of radioindicators were suggested and preliminary tested. The new way of synthesis of radiochromic derivatives of aziridine was developed and series of target compounds synthesized.

• The KIPS Transactions:PartA
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• v.8A no.2
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• pp.147-156
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• 2001

A high performance routing switch is an essential device to either the high performance parallel processing or communication networks that handle multimedia transfer systems such as VOD. The high performance routing chip called STC104 is a typical example in the technical aspect which has 32 bidirectional links of 100Mbps transfer sped. It has exploited new technologies, such as wormhole routing, interval labeling, and adaptive routing method. The high speed router has been applied into some parallel processing system as a single chip. However, its performance over the various interconnection networks with multiple routing chips has not been studied. In this paper, the strucrtures and characteristics of the STC104 have been investigated in order to evaluate the high speed router. Various topology of the STC104, such as meshes, torus, and N-cube are defined and constructed. Algorithms of packet transmission have been proposed based on the interval labeling and the group adaptive routing method implemented in the interconnected network. Multicast algorithms, which are often requited to the processor networks and broadcasting systems, modified from U-mesh and U-torus algorithms have also been proposed overcoming the problems of point-to-point communication.

• Journal of Korea Entertainment Industry Association
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• v.14 no.1
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• pp.75-89
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• 2020

As Marvel Cinematic Universe (MCU) Phase 3 concluded in 2019, it is time to systematically analyze the phenomenal storytelling of the franchise. In order to identify the structure of the continuous stories focusing on 'Iron Man', the central character of MCU Phase 1-3, this study used the "Save the Cat (STC)" paradigm as the tool for narrative analysis. The eight films with 1,066 minute-run time in total was analyzed based on the 15-beat STC paradigm by adjusting the distance ratio between each beat of its prototype originally based on standard films of 110 minute-run time. The results reveal that all 15 beats of the combined texts were fairly properly discovered in the positions suggested by the adjusted STC paradigm. Moreover, through the investigation, the vast text was able to be analyzed in a more comprehensive manner in the process of reconfirming the meaning of the dramatic reversals corresponding to each beat against the entire narrative. As expected, the STC paradigm proved to be a meaningful signpost for plot drives even for such a vast text. Therefore, it is believed that application of this paradigm would help not only analyze but also design other serialized franchises as well. Prior to that, however, it would be necessary to further examine the combined texts for other major characters in MCU or other franchises designed in a similar form to MCU movies through the same paradigm to verify effectiveness of such application.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.5
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• pp.475-480
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• 2014

This study proposes a new synthetic test circuit (STC) for HVDC thyristor valve tests. The conventional STC with a 2-phase chopper requires a 3-phase transformer, a 3-phase diode rectifier, and an IGBT to facilitate the off state of an auxiliary thyristor. In the proposed STC, these three components are replaced with one diode and one resistor, which result in the simplified implementation of the hardware of the STC. Simulation and experimental results demonstrate the validity of the proposed scheme.

• Proceedings of the IEEK Conference
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• summer
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• pp.302-309
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• 2004

The transmission capacity of wireless communication systems may become dramatically high by employ multiple transmit and receive antennas with space-time coding techniques appropriate to multiple transmit antennas. For large number of transmit antennas and at high bandwidth efficiencies, the receiver may become too complex whenever correlation across transmit antennas is introduced. Reducing decoding complexity at receiver by combining array processing and space-time codes (STC) helps a communication system using STC to overcome the big obstacle that prevents it from achieving a desired high transmission rate. Multi-carrier CDMA (MC-CDMA) allows providing good performance in a channel with high inter-symbol interference. Antenna array, STC and MC-CDMA system have a similar characteristic that transmit-receive data streams are divided into sub-streams. Thus, there may be a noticeable reduction of receiver complexity when we combine them together. In this paper, the combination of array processing and STC in MC-CDMA system over slow selective-fading channel is investigated and compared with corresponding existing MC-CDMA system using STC. A refinement of this basic structure leads to a system design principle in which we have to make a trade off between transmission rate, decoding complexity, and length of spreading code to reach a given desired design goal.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.185-189
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• 2003

We examined the inhibitory activities against monoamine oxidase (MAO) of Morus alba in vitro and in vivo methods. Methanolic extract of M. alba showed significantly inhibitory activities on MAO-A and MAO-B that were prepared from rat brain and liver in vitro. The inhibitory activities were measured by serotonin and benzylamine as substrates, respectively. MAO-A and MAO-B activities were potently inhibited by ethylacetate extracts of M. alba in vitro tests. Those activities in vivo tests have different tendency each other. MAO-A activity was increased by the oral administration of methanolic extract of M. Alba, while, MAO-B activity was decreased. Consequently, we can suggest that M. alba may have the effects on the inhibitory activities against MAO both in vitro and in vivo.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.132.1-132.1
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• 2003

Novel trans-ditrifluoroacetato, malonato-1, 4-butanediamine Pt(IV) complex, K104 was synthesized as a chemotherpeutic. The cytotoxicity of K104 against various human cancer cell lines were evaluated by MTS assay in vitro. The IC50 values of K104 ranged 15.83-25.83 $\mu\textrm{M}$, compared to CBCDA ranged 23.24-69.6 $\mu\textrm{M}$. Among several cancer cell lines, K104 showed more potent than CBCDA in colon cancer cell lines. (omitted)