• The KIPS Transactions:PartC
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• v.18C no.1
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• pp.51-60
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• 2011

In this paper, we propose a P4P based P2P system for live multimedia streaming services. In order to satisfy the strict requirement of delay in live multimedia streaming, in the proposed scheme, the P4P server of network provider provides the network status information related to delay and congestion links to P2P system in addition to the information to optimize the network resource utilization. The P2P system server, then, makes the peering suggestion based on the information from the network server. Also, we propose a playback synchronization mechanism that enable each peer to start the playback within the limited variation from the playback positions of source peer. Through the simulation results, it is shown that the proposed scheme not only deals with the original objective of the P4P framework, i.e., effective network utilization, but also the live multimedia streaming requirements. It enhances the playback continuity, and reduces the playback start-up latency and the control overhead. In addition, the proposed scheme reduces the variation in playback positions of the peers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.5
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• pp.199-204
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• 2022

A new three-dimensional Gd-MOF, [Gd(p-XBP4)₄(H₂O)]·W(CN)₈; (1; p-XBP4 = N,N'-p-phenylenedimethylenbis (pyridin-4-one)) has been synthesized by slow-evaporation and its crystal structure was characterized by single-crystal X-ray diffraction (SCXRD) analysis. For each Gd^III ion, there are seven coordination sites, which are occupied by six oxygen atoms of six p-XBP4 ligands and one oxygen atom from the water molecule. The [W(CN)₈]^3- anion exists for charge balance with cationic framework. The Gd^II ions are interconnected by the p-XBP4 ligand to form the three-dimensional structure. Considering the magnetic property of lanthanide ions, magnetic studies of Gd-MOF were investigated by direct-current (DC) magnetic susceptibilities measurements.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.6
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• pp.225-230
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• 2022

A new two-fold interpenetrating two-dimensional (2D) Tb(III) metal-organic framework (MOF), [Tb(p-XBP4)_2.5(H₂O)₂]·W(CN)₈ (1), was prepared using a p-XBP4 (N,N'-p-phenylenedimethylenbis(pyridin-4-one)), Cs₃[W(CN)₈], and Tb(NO₃)₃·6H₂O. The single crystal X-ray diffraction indicated that Tb-MOF exhibits a unique two-fold interpenetrating 2-D framework. It was also characterized through Fourier transform infrared spectroscopy (FTIR), and single and powder X-ray diffraction. To probe the molecular magnetic behavior, the magnetic properties of Tb-MOF were investigated by direct-current (DC) and alternating-current (AC) magnetic susceptibilities measurements and discussed.

• Korean Journal of Crystallography
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• v.10 no.1
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• pp.51-55
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• 1999

Cesium titanium(III) pyrophosphate 화합물인 CsTiP2O7을 합성하고 X절 회절법을 이용하여 그 결정구조를 해석하였다. 이물질은 단사정계의 P21/a 공간군으로 결정화되었고 a=8.369(2) , b=10.208(2) , c=7.752(1) , β=104.77(2)o, V=640.4(2) 3, and Z=4이다. 이 물질의 구조는 모서리를 공유하고 있는 TiO6 팔면체와 P2O7 pyrophosphate group들로 구성된 framework로 구성되어 있으며 그 결과로 형성된 tunnel 안에는 Cs+이온이 존재한다. CsTiP2O7은 ATiP2O7(A=K, Rb)와 KAIP2O7 그리고 AMoP2O7(A=K, Rb, Cs)등 다른 +3금속 pyrophosphate들로 유사한 구조를 가지고 있다. 이 물질은 [Cs+][Ti3+][P2O74-]의 식으로 표현할 수 있다.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.21-31
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• 2007

This Paper presents an SOA framework that enables smooth provision of service to ordinary users while also replacing the current B2B environment-oriented SOA framework. To that end, the proposed SOA will be reviewed for its concept, characteristics, and components. Key to its design is that it will be implemented using the prospective next-generation P2P platform known as JXTA. The proposed framework includes all the basic functions of other SOA frameworks, and will make Provision and use of services more easy compared with other frameworks. Under this service, data and applications controlling these data are provided in an enabling format, thereby addressing security problems. Another advantage of this proposed framework is that each peer is able to play all roles of a service provider, service client, and service registry.

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.57-63
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• 1996

The compound titanium (III) pyrophosphate, KTiP2O7 has been prepared and the crystal structure of the compound has been determined by the X-ray diffraction techniques. It crytallizes in the space group P21/a of the monoclinic system with four formula units in a cell of dimensions a=8.210(3), b=10.292(2), c=7.434(1)Å and β=106.71(2)°. The structure consists of the framework possessing corner-sharing octahedral TiO6 and pyrophosphate groups. As a result, a tunnel structure has been constructed and the K+ cations reside inside the tunnel. KTiP2O7 is isostructural with other trivalent metal pyrophosphates such as KAlP2O7 and RbTiP2O7 but the size difference of the alkali metals causes the variation in the structure. The classical charge balance of the compound can be described as [K+][Ti3+][P24O74-].

• Journal of Service Research and Studies
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• v.13 no.4
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• pp.70-96
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• 2023

Recently, the high turnover rate of nursing staff and the problems caused by increased job stress have been highlighted as social issues, and the problem of 'Taeoom' in nursing organizations has received increasing attention. Therefore, the purpose of this study is to propose a solution to the Taeoom problem, including bullying in the nursing work environment, as there is an urgent need to find a solution to prevent and overcome this problem. For this purpose, based on the S-O-R framework and previous studies, job stress and turnover intention were derived as outcome variables of Taeoom and communication competence as an antecedent factor, and a research model was constructed with the expectation that mindfulness and social support would serve as moderating variables to help overcome this problem. Data were collected through a survey of 300 nurses who had experienced Taeoom within the past year, and the hypotheses were tested using a structural equation model. The results revealed that the higher the communication competence of nurses, the less they perceived the damage of Taeoom, and that the damage caused by Taeoom leads to turnover intention through high job stress. In addition, mindfulness and social support significantly attenuated the positive effects of burnout on job stress and job stress on turnover intention, respectively. The significance of this study is that it proposed an extended P-S-O-R framework by adding a prevention stage to the existing S-O-R framework, and further tested the moderating effects of mindfulness and social support variables. It is expected that the findings of this study will provide concrete guidelines to prevent and overcome the Taeoom problem that can be applied in practice.

• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.55-58
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• 1993

In order to determine the cobalt substituting site in $AlPO_4-5$ framework, ASED-MO theory has been used. The substitution of cobalt for aluminum is energetically more favorable than that for phasphorous. The stabilized energy of the former is 51 eV lower than that of the latter. The calculated net charge was +1.27 for Al, +0.85 for P, and +1.56 for Co, respectively. The valence electron population (VEP), reduced overlap population (ROP) and net charge for the charged cluster models were compared for $AlPO_4-5$ and $CoAlPO_4-5$ systems. Then, twe find that the covalency of P-O bond was greater than that of Al-O bond.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.791-793
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• 1997

• The Journal of Advanced Prosthodontics
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• v.6 no.1
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• pp.22-29
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• 2014

PURPOSE. This study aimed to investigate the potential clinical application of digitized silicone rubber impressions by comparing the accuracy of zirconia 3-unit fixed partial dentures (FPDs) fabricated from 2 types of data (working model and impression) obtained from a laser scanner. MATERIALS AND METHODS. Ten working models and impressions were prepared with epoxy resin and vinyl polysiloxane, respectively. Based on the data obtained from the laser scanner (D-700; 3Shape A/S, Copenhagen, Denmark), a total of 20 zirconia frameworks were prepared using a dental CAD/CAM system (DentalDesigner; 3shape A/S, Copenhagen, Denmark / Ener-mill, Dentaim, Seoul, Korea). The silicone replicas were sectioned into four pieces to evaluate the framework fit. The replicas were imaged using a digital microscope, and the fit of the reference points (P1, P2, P3, P4, P5, P6, and P7) were measured using the program in the device. Measured discrepancies were divided into 5 categories of gaps (MG, CG, AWG, AOTG, OG). Data were analyzed with Student's t-test ($\alpha$=0.05), repeated measures ANOVA and two-way ANOVA (${\alpha}=0.05$). RESULTS. The mean gap of the zirconia framework prepared from the working models presented a narrower discrepancy than the frameworks fabricated from the impression bodies. The mean of the total gap in premolars (P=.003) and molars (P=.002) exhibited a statistical difference between two groups. CONCLUSION. The mean gap dimensions of each category showed statistically significant difference. Nonetheless, the digitized impression bodies obtained with a laser scanner were applicable to clinical settings, considering the clinically acceptable marginal fit ($120{\mu}m$).