• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.321-329
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• 2005

Ornithine decarboxylase (ODC) antizyme is a key regulatory protein in the control of cellular polyamines. We have isolated two distinct ODC antizyme cDNA clones (AZS and AZL) from a flounder (Paralichthys olivaceus) brain cDNA library. Their sequences revealed that both clones required translational frameshifting for expression. Taking + 1 frameshifting into account, AZS and AZL products were 221 and 218 amino acid residues long, respectively, and shared $83.3\%$ amino acid sequence identity. Comparison of the structure and nucleotide sequence of the antizyme genes showed that the genes were highly conserved in flounder, zebrafish, mouse, and human. A phylogenetic tree was constructed, based on the antizyme amino acid sequences from various species. The presence of the two types of antizyme mRNA species in brain, kidney, liver, and embryo was confirmed by using the reverse transcription­polymerase chain reaction (RT-PCR) and Northern blot analysis. Recombinant proteins of flounder ODC antizymes, containing His-Nus-S tag at the amino-terminus, were overexpressed as His-AZL and His-AZS fusion proteins in Escherichia coli BL21 (DE3) pLys by using the pET­44a(+) expression vector.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.6
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• pp.48-53
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• 1988

In a previous report, the properties of vegetable oils as diesel fuel substitutes were investigated and the basic load performance of a diesel engine was examined using vegetable oil. The results show that despite of the long term chain hydrocarbon structure and large droplet size due to high viscosity, vegetable oils have good basic performance and exhaust emissions, however they cause serious problems as carbon deposit buildup, they have poor durability, and also poor thermal efficiency. In this paper, the startability and engine durability with long term operation was tested by physical methods for reducing viscosity when vegetable oil was used as compared against diesel fuel. The results obtained in this investigation may be stated as follows; (1) There is no problem in startability when vegetable oil was used as diesel fuel substitutes as far as fuel temperature is higher than 30.deg. C (2) The carbon deposits were most extensive at lower loads and lower engine speeds, and deposit buildup more heavily on the cooler parts of the combustion chamber wall. (3) Blends with 25% diesel fuel and 20v-% ethanol are effective in reducing the carbon deposit buildups. (4) Significant improvement in carbon deposit and piston ring stick can be obtained by heating fuel(200.deg.).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.1869-1880
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• 2014

Wireless communication is one of most active areas in modern communication researches, QoS (Quality of Service) assurance is very important for wireless communication systems design, especially for applications such as streaming video etc., which requires strict QoS assurance. The modern wireless networks multi-layer protocol stack structure results in QoS metrics layered and acting in cascade and QoS metrics vertical mapping between protocol layers. Based on virtual buffer between protocol layers and queuing technology, a unified layered QoS mapping framework is proposed in this paper, in which we first propose virtual queue concept, give a novelty united neighboring protocol layers QoS metric mapping framework, and analysis method based on dicerete-time Markov chain, and numerical results show that our proposed framework represents a significant improvement over previous model.

• The Journal of the Korea Contents Association
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• v.7 no.11
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• pp.120-129
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• 2007

As the Internet is more embedded in people's lives, users draw on new Internet applications to express themselves through user-created contents(UCC). UCC is defined as content that is made publicly available over the Internet, reflects a certain amount of creative effort and is created outside of professional practices. This study describes the rapid growth of UCC as well as its increasing role in network-based communication. Based on the definition of UCC and the structure of emerging value chain, a taxonomy of UCC businesses is presented : UCC e-marketing business, UCC publishing business, UCC e-retailing business, and UCC development software business. This paper concludes with implications for platform and internet access providers.

• Journal of Korea Port Economic Association
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• v.18 no.1
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• pp.107-134
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• 2002

Globalization of the industry induces the internationalization of any given manufacturing company's supply chain. Development of e-Commerce and Information Technology (IT) changes the logistics structure, making logistics information systems essential. Web-based connectivity and supply chains based on new technologies are becoming essential in the logistics industry. Customers are driving the implementation of systems to ensure timely, thorough, and accurate information, often with immediate access; in response, the Internet has propagated tracking and tracing systems. Value-added services are the key to successful intermediary activities. The nationwide Integrated Logistics Information System (ILIS) aimed to utilize existing and future information infrastructure and knowledge bases to build an integrated logistics information network that would provide comprehensive logistics information services for shippers and carriers in order to improve the efficiency of both inventory and information flows in their supply chains. The ILIS, as one of the seven national information networks, has provided various services, particularly services related to import/export and clearance. Though a survey concerning logistics information services shows rather positive results, shippers and carriers still require better services and reductions in EDI prices. Therefore, the role of the ILIS needs to be re-defined. Short-term plans for the ILIS contain ICD services and XML/EDI services, which are described in detail.

• Macromolecular Research
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• v.14 no.1
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• pp.73-80
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• 2006

Sulfonated poly(ethylene glycol) (PEG-$SO_{3}$) grafted polyrotaxanes (PRx-PEG-$SO_{3}$) were prepared in order to utilize the unique properties of PEG-$SO_{3}$ and the supramolecular structure of PRx, in which PEG-$SO_{3}$ grafted $\alpha$-cyclodextrins ($\alpha$-CDs) were threaded onto PEG segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) chain capped with bulky end groups. Some of the PRx-PEG-$SO_{3}$ demonstrated a higher anticoagulant activity in case of PRx-PEG-$SO_{3}$ (P 105), and compared with the control they showed a lower fibrinogen adsorption in PRx-PEG-$SO_{3}$ (F68) and a higher binding affinity with fibroblast growth factor. The obtained results suggested that polyrotaxane incorporated with PEG-$SO_{3}$ may be applicable to the surface modification of clinically used polymers, especially for blood/cell compatible medical devices.

• Polymer(Korea)
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• v.26 no.1
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• pp.80-87
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• 2002

A comparative study using electron-beam(EB) and thermal curing techniques was carried out to determine the effect of cure behavior and thermal stability of epoxy resins. In this work, benzylquinoxalinium hexafluoroantimonate(BQH) was used as a latent cationic catalyst for an epoxy resin. According to the thermogravimetric analysis(TGA), the decomposed activation energy based on Coats-Redfern method was higher in the case of thermal curing technique. This could be interpreted in terms of slow thermal diffusion rate resulted from high crosslink density of the thermally cured epoxy resin. However, the increase of hydroxyl group in the epoxy resin cured by EB technique was observed in near-infrared spectroscopy(NIRS) measurements, resulting in improving the stable short aromatic chain structure, integral procedural decomposition temperature, and finally ductile properties for high impact strengths.

• Polymer(Korea)
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• v.25 no.4
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• pp.528-535
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• 2001

Polyurethane specimens were mainly composed of polyol, MDI, silicone surfactant, and water. The effects of ethylene glycol on the cell size, forming magnification, cream time, gel time, take free time, final free rising height, and reactive temperature were investigated. The cyclopentane was used for PU foam as a physical blowing agent. The components were hand-mixed at about 5000 rpm within 4 seconds at room temperature. The mixtures with various ethylene glycol contents were foamed in the wood mold. When the index of isocyanate was fixed, as the amount of ethylene glycol increased, cell size and thermal conductivity were decreased by about 5.1% and 14%, respectively.

• Macromolecular Research
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• v.15 no.7
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• pp.633-639
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• 2007

A variety of NMR techniques were applied to the micro-chemical structural characterization of polyanilines prepared via an efficient synthetic method in a self-stabilized dispersion medium in which the polymerization was conducted in a heterogeneous organic/aqueous biphasic system without any stabilizers. Here, the monomer and growing polymer chain were shown to function simultaneously as a stabilizer, imparting compatibility for the dispersion of the organic phase, and as a form of flexible template in an aqueous reaction medium. Polymerizations predicated on this concept generated polyanilines with a low defect content: solution state $^{13}C-NMR$ and solid $^{13}CDD/CP/MAS$ spectroscopy indicated that the synthesized HCPANi and its soluble derivative, HCPANi-t-BOC, evidenced distinctly different NMR spectra with fewer side peaks, as compared to conventionally prepared PANis, and the complete structural assignments of the observed NMR peaks could be determined via the combination of both 1D and 2D techniques. Ortho-linked defects in HCPANi were estimated to be as low as 7%, as shown by a comparison of the integration of the carbonyl carbon resonance peaks.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.112-121
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• 2008

Nowaday the supply chain competitiveness is emphasized more and more than a company's own competitiveness. One of the most important processes in import and export is a publication over the Bill of Loading. In the publication of those bills S/R(shipping request) and check B/L for reviewing are circulated among consignors, forwarders, shipping companies and airlines by fax and e-mail. Or there should be expensive a One to One system, like an EDI. Each party has to re-input S/R data to their own systems and check it several times. The S/R data are converted digital to analog type and analog to digital repeatedly to check in the process. As the process goes by there can be not only input data errors but also waste of time and cost. ECR(electronic character recognition) is a technology can solve the Problem. Considering the data structure of documents in many systems used ECR samples SIR data from documents written in the digital type. But it is not enough with it only. To make N to N composition in reality more efficient we make a documents hub on the web reengineering the existing process to One to One relation. The ECR documents hub system has given us beneficial effects over a year throughout a field test.