• 한국산림과학회지
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• 제101권3호
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• pp.344-355
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• 2012

임목수확작업시스템 구축과 효율적인 임목수확작업 기술을 보급하기 위해 타워야더 및 스윙야더 등에 의한 전목집재작업시스템과 굴삭기 그래플 등에 의한 단목집재작업시스템의 작업시간 및 공정을 분석하였다. 전체 조사작업시간을 기준으로 분석한 1 cycle당 작업시간은 전목집재작업시스템에서 체인톱에 의한 벌목 46.6초/cycle, 타워야더에 의한 집재 480.6초/cycle, 스윙야더에 의한 집재 287.4초/cycle, 체인톱에 의한 조재 155.14초/cycle로 나타났다. 또 한 단목집재작업시스템에서는 체인톱에 의한 벌목 및 조재 225.65초/cycle, 굴삭기 그래플에 의한 단목집재 4,972초/cycle, 지엽집재 3,143초/cycle로 나타났으며, 바퀴식 미니포워더에 의한 소운재 4,688초/cycle, 굴삭기 그래플 및 소형운재차에 의한 소운재 2,118초/cycle로 나타났다. 전목집재작업시스템의 작업공정에서 체인톱에 의한 평균 벌목공정이 $57.89m^3$/일, 타워야더에 의한 평균 집재공정이 $20.3m^3$/일, 스윙야더에 의한 평균 집재공정이 $31.55m^3$/일, 체인톱에 의한 평균 조재공정이 $20.3m^3$/일로 나타났다. 또한, 단목집재작업시스템의 작업공정에서 체인톱에 의한 평균 벌목 및 조재공정이 $11.96m^3$/일, 굴삭기 그래플에 의한 평균 단목집재공정이 $34.75m^3$/일, 굴삭기 그래플에 의한 평균지엽수집공정이 $37.66m^3$/일, 굴삭기 그래플에 의한 평균 작업로의 개설공정이 73.8 m/일로 나타났으며, 바퀴식 미니포워더와 굴삭기 그래플 및 소형 운재차에 의한 평균 소운재 작업공정이 각각 $15.73m^3$/일과 $65.03m^3$/일로 나타났다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.45-46
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• 2002

Based on the fact that the lubricant molecular is with a chain structure, the physical and mathematical models for the thin film lubrication are set up after the analysis of relationship of the chain length and the film thickness is carried out. The basic equations of fluid mechanics with the rotation terms are used to derive the equivalent Reynolds equation. The results show that the load carrying capacity has a significant increase while the length effect is considered. Finally, the calculated results are compared with the experimental results and they have the same tendency.

• 한국경영과학회지
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• 제29권3호
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• pp.63-78
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• 2004

This paper deals with a supplier-managed inventory(SMI) control for a two-echelon supply chain model with a service facility and a single supplier. The service facility is allocated to customers and provides a service using items of inventory that are purchased from the supplier, Assuming that the supplier knows the information of customer queue length as well as inventory position in the service facility at the time when it makes a replenishment decision, we identify an optimal replenishment policy which minimizes the total supply chain costs by reflecting these information into the replenishment decision. Numerical analysis demonstrates that the SMI strategy can be more cost-effective when the information of both customer queue length and inventory position is shared than when the information of inventory position only is shared.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1935-1939
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• 2006

The gene encoding the extracellular medium-chain-length poly(3-hydroxyalkanoate) (MCL-PHA) depolymerase of Pseudomonas luteola Ml3-4, $phaZ_{plu}$, was cloned and analyzed. It was found to be 849 bp, with a deduced protein of 282 amino acids, and was revealed to have a typical leader peptide at its N terminus. The amino acid sequence of $PhaZ_{plu}$ revealed relatively low identity (69 to 72%) with those of other Pseudomonas MCL-PHA depolymerases. In comparison with the amino acid sequences of all available MCL-PHA depolymerases, the depolymerase was found to consist of three domains in sequential order; signal peptide, an N-terminal substrate binding domain, and a catalytic domain, indicating that $PhaZ_{plu}$ belongs to the type IV depolymerases family. The enzyme also contained Asn as an oxyanion hole amino acid.

• 한국경영과학회지
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• 제30권4호
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• pp.1-14
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• 2005

We propose a VSSI-CRL(Variable Sampling Size and Samplina Interval-Conforming Run length) synthetic control chart in order to improve the statistical characteristics of both the VSSI chart and the CRL synthetic chart. The VSSI-CRL chart utilizes VSSI sampling scheme, but it produces a signal only when the CRI is less than a given limit. An algorithm for calculating the ARL(Average Run length) and ATS(Average Time to Signal) of the VSSI-CRL chart is developed by employing Markov chain method. We present some lemmas for describing the statistical characteristics of the VSSI-CRL chart under in-control state. A procedure for designing the VSSI-CRL chart is proposed based on the lemmas. Extensive comparative studios show that the VSSI-CRL chart is superior to the CRL synthetic chart or the VSSI chart in general, and is comparable to the EWMA chart in ATS performance.

• Korea-Australia Rheology Journal
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• 제21권4호
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• pp.235-244
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• 2009

Miscible polymer blends still have heterogeneity in their component chain concentration in the segmental length scale because of the chain connectivity (that results in the self-concentration of the segments of respective chains) as well as the dynamic fluctuation over various length scales. As a result, the blend components feel different dynamic environments to exhibit different temperature dependence in their segmental relaxation rates. This type of dynamic heterogeneity often results in a broad glass transition (sometimes seen as two separate transitions), a broad distribution of the local (segmental) relaxation modes, and the thermo-rheological complexity of this distribution. Furthermore, the dynamic heterogeneity also affects the global dynamics in the miscible blends if the component chains therein have a large dynamic asymmetry. Thus, the superficially simple miscible blends exhibit interesting dynamic behavior. This article gives a brief summary of the features of the segmental and global dynamics in those blends.

• 한국식품영양과학회지
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• 제22권6호
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• pp.792-796
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• 1993

The synthesis alcohol-oxidase[EC 1.1.3.13] was investigated in the yeasts, Candida boidinii CBS 8106 and C. boidinii CBS 2428, during growth on different carbon sources. Alcohol-oxidase was undetectable in all strains submitted to the test in the mineral salts medium containing 1.0% glucose, but its production was rapidly increased when the carbon source was changed glucose to 1.0% methanol after 24hrs of incubation. When cells were grown on the various carbon sources (glucose, xylose, lactose, glycerol, galactose, saccharose, sorbose, lactic acid or acetic acid), the alcohol-oxidase activity was undetected. These carbon sources together with methanol yielded far better synthesis of alcohol-oxidase than in the case of carbon sources alone. Alcohol-oxidase was active towards alcohol of shorter alkyl-chain length than C5 and unsaturated alcohols. Its affinity for these alcohols decreased with the increasing length of the alkyl-chain. The apparent Km values for the methanol of Candida boidinii CBS 8106 and C. boidinii CBS 2428 were 1.96 and 1.21, respestively.

• Bulletin of the Korean Chemical Society
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• 제13권3호
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• pp.259-265
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• 1992

Cyclic voltammetric behavior of symmetric (dimethyl, diheptyl, dioctyl, dibenzyl) and asymmetric (methyloctyl, methyldodecyl, methylbenzyl) viologens was investigated in homogeneous aqueous solution and sodium dodecyl sulfate (SDS) micellar media. In SDS-free 0.1 M NaCl solutions, the reduction potential is less negative as the chain length of alkyl substituent is longer. This is due to the stabilization of the reduced cationic radical and neutral form of viologen by adsorption on electrode surface. The adsorbed species show the "aging-effect". With the exceptions of methyldodecyl viologen and methylbenzyl viologen, the viologens show strong tendency of conproportionation reaction between viologen dications and neutral forms. In cases of methyldodecyl viologen and methylbenzyl viologen, the conproportionation reaction is kinetically disfavored, though it is thermodynamically favorable. SDS micelles dissolve the adsorbed species and the viologens exhibit two reversible redox processes in SDS micellar solutions. The reduction potentials of viologens in SDS micellar solutions depend little on the length of alkyl chain. Benzyl-substituted viologens are more easily reduced than the alkyl substituted viologens, presumably due to electron-withdrawing character of benzyl group.

• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1806-1810
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• 2002

We have described the synthesis and biological activity of novel retinamide . The retinamide derivatives were synthesized by introducing functional side chains into the 4-hydroxy group of 4-HPR. The activities could be dependent on the side chain length, functional group, and hetero atom. The antiprolife-rative potential of the derivatives was assessed by MTT assay in HCT116 cancer cell lines.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1989년도 제2차 학술발표초록집
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• pp.47-48
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• 1989