• Journal of the Korean Magnetic Resonance Society
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• v.2 no.1
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• pp.50-58
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• 1998

The systematic chirality investigations were made on the basic of the fact that zinc-binding tallysomycin (ZnTLMA) could have chiral centers (Zn, NC3, C6) at possible 4-, 5-, and 6-coordination models. Although our NMR data exhibit that the ligation sites are ${\beta}$-aminoalanine, ${\beta}$-hydroxyhistidine, and pyrimidine moiety, all possible coordination modes were tested out to see what kind of chiralities on NC3-C6 are favorable to each coordination mode. Tests were also made that take into account the specific configuration of functional groups, including ${\beta}$-aminoalanine, sugar ring, and ${\beta}$-hydroxyhistidine. Tests were finally extended to zinc-water binding and specific conformational studies by introducing various hydrogen bonding networks associated with the propionamide side chain and the carbamide group of mannose. Results of systematic chirality investigations exhibit that the S-S configuration of NC3-C6 is favorable to all of coordination models, but the R-S configuration, if exists at all, should have internal strain on C6 chiral center.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.536-539
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• 2004

IEEE 802.11 Point Coordination Function (PCF) mode is defined to support time bounded traffic, such as voice in wireless LANs. The poll scheduling plays an important role in IEEE 802.11 PCF mode operation. This paper proposed a Multicast Polling Scheme (MPC) to increase the performance of wireless LANs. Moreover, we proposed a polling schedule scheme for our proposed multi-poll to serve real-time traffic. The results show that the proposed mechanism is more efficient than the original IEEE 802.11 PCF.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.629-633
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• 2002

• Journal of Digital Contents Society
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• v.18 no.2
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• pp.365-371
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• 2017

IEEE 802.11 Wireless Local Area Network (WLAN) adopts Power Saving Mode(PSM) to save the power. Unlike existing PSM, this paper proposes a new scheme for the power saving of the Mobile Host(MH) when a MH performs the data transmission after the competition-based DCF(Distributed Coordination Function) and competition free-based PCF(Point Coordination Function). In this paper, The proposed scheme estimates the distance between the MH with the authority of data transmission and the Access Point(AP) and then adaptively controls the power of the MH considering the distance. Through the simulation result, we find that the proposed scheme consumes the smaller transmission power and has the similar success rate of packet transmission when it is compared to the existing scheme which uses the same power without the consideration of the distance.

• The Research Journal of the Costume Culture
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• v.3 no.2
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• pp.277-291
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• 1995

The purpose of this study is to consider the internal meaning and the external from of Dualism in Unisex Mode : to investigate the dualistic expression appeared on the Unisex Mode by analyzing the general fashion magazine. The results of the study were as follows : First, the phenomenon of Dualism in Unisex Mode may be clues indication that some roles, once assigned exclusively to either males or females, are becoming mutually shared, or what may be called human roles. Second, the expression of Dualism in Unisex Mode whether direct away of symbolic way is represented by metaphoric manner such as unisex look(mono sex look, or trans sex look) with spirit of the time’s. Third, the formality and contents that related dualistic mode shows a various method in style, coordination of texture or item.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1784-1786
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• 2008

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.155-161
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• 2008

An automated healthcare monitoring is demand of time, lot of problems occurring just because of less monitoring of patients health condition on time. In this paper an embedded healthcare service is proposed by an iSCSI protocol on an automated multi-agent coordination by resource-constrained devices controlled system for healthcare service. The coordination between the resource constrained devices (e.g. PDA, SmartPhone, Tablet PC), and automated agents are maintained by a two-way handshaking mode iSCSI protocol. The automated health care control could be useable, and beneficial in the repetitive way. A fully centralized control is not applicable for this kind of approach.

• Bulletin of the Korean Chemical Society
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• v.19 no.5
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• pp.565-568
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• 1998

Novel mononuclear metal complexes with the formula $[M(Ph_2PC_6H_4NC_3H_6NC_6H_4PPh_2)]$ (M=Pd (1); M=Pt (2)) were obtained when N,N'-bis[2'-(diphenylphosphino)phenyl]propane-1,3-diamine, I was mixed with cisdichlorobis(diethylsulfide)palladium and platinum in the presence of NEt3. Two mononuclear metal compounds with the fomula [M(Ph2PC6H4NH)(SEt2)Cl] (M=Pd (3); M=Pt (4)) were synthesized from $M(SEt_2)2Cl_2$ and N-(2'-diphenylphosphinophenyl)-4-amino-1,1,1,5,5, 5-hexafluoro-3-penten-2-one, II by the elimination reaction of hexafluoro pentenone. The X-ray single crystal structures of 1 and 4 are described. X-ray single crystal diffraction analyses reveal that compound 1 is a mononuclear palladium compound with P,N,N,P-coordination mode and 4 is a mononuclear platinum compound with P,N-coordination mode.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.3
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• pp.100-106
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• 2013

In this paper, in order to analyze lightning impulse response characteristics in combined installations of SPDs and RCDs, surge protection coordination between SPDs and RCDs are experimentally investigated by using the combination wave generator. Six different types of single-phase residual current operated circuit-breakers with integral overcurrent protection for household and similar uses(RCBOs) being present on the domestic market are tested according to KS C IEC 61009-1 standard. As a result, when a class I SPD is located on the source side of an RCBO, all kinds of specimens are able to provide the proper coordination between the SPD and RCBOs without nuisance tripping, unintended operation or damage due to test impulse currents. However, in the case that the class II SPD is located on the load side of RCBOs, a lot of L-N mode injected currents is split into the RCBO, and a few RCBOs are damaged. Coordination between SPDs and RCDs is not valid and a role of SPDs is of no use. When combining SPDs with RCDs, it is necessary to select SPDs and RCDs in consideration of the protection voltage level of metal oxide varistor embedded in RCDs.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.2
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• pp.237-245
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• 2007

In this paper, a modified PCF (Point Coordination Function) MAC (Medium Access Control) Protocol is proposed to support the multiple direct link communication between STAs (STAtions) in infrastructure mode IEEE 802.11 wireless LANs. By the proposed MAC protocol, the direct link communication between STAs, which are located within the communication range of each other, is allowed without the use of AP (Access Point) as a relay. Moreover, when multiple direct data communication between STAs can be simultaneously performed with a sufficiently small interference, multiple simultaneous direct link communication is allowed for the efficient use of radio bandwidth. AP polls STAs to grant the transmission opportunities using the direct link communication by transmitting the polling frames to STAs. An efficient polling method for granting the transmission opportunities to STAs is proposed to reduce the number of the polling frame transmissions and enhance the PCF MAC performance.