• Korean Journal of Construction Engineering and Management
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• v.18 no.3
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• pp.84-94
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• 2017

Recently, domestic construction companies have increasingly engaged in international PPP projects a result of both uncertainties in the domestic construction market and low competitiveness in international EPC project business. These international PPP projects usually require long-term preparations and substantial sales costs, which make it important for decision-makers to select winning-award potential project in early stage of the projects. However, most previous research has analyzed success factors in terms of project development across all stages. Thus, this study investigated 28 success factors of 4 categories in the early stage of 31 international PPP projects. First, results indicate that unsolicited PPP projects require better implementation capabilities and financial conditions compared to solicited PPP projects. Second, implementation capability is important because it is not easy to improve as the project proceeds. Third, commercial conditions are identified as important even if conditions are not fixed in the early stage of PPP projects. Fourth, non-commercial conditions, strategy, and public interest are not found to be meaningful in the early stage of PPP projects because they can vary as the project proceeds. This study helps to improve selection criteria aimed towards more winning-award potential project in the early stage of international PPP projects.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1867-1876
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• 2017

Most of the biosynthetic pathways for secondary metabolites are influenced by carbon metabolism and supply of cytosolic NADPH. We engineered carbon distribution to the pentose phosphate pathway (PPP) and redesigned the host to produce high levels of NADPH and primary intermediates from the PPP. The main enzymes producing NADPH in the PPP, glucose 6-phosphate dehydrogenase (encoded by zwf1 and zwf2) and 6-phosphogluconate dehydrogenase (encoded by zwf3), were overexpressed with opc encoding a positive allosteric effector essential for Zwf activity in various combinations in Streptomyces lividans TK24. Most S. lividans transformants showed better cell growth and higher concentration of cytosolic NADPH than those of the control, and S. lividans TK24/pWHM3-Z23O2 containing zwf2+zwf3+opc2 showed the highest NADPH concentration but poor sporulation in R2YE medium. S. lividans TK24/pWHM3-Z23O2 in minimal medium showed the maximum growth (6.2 mg/ml) at day 4. Thereafter, a gradual decrease of biomass and a sharp increase of cytosolic NADPH and sedoheptulose 7-phosphate between days 2 and 4 and between days 1 and 3, respectively, were observed. Moreover, S. lividans TK24/pWHM3-Z23O2 produced 0.9 times less actinorhodin but 1.8 times more undecylprodigiosin than the control. These results suggested that the increased NADPH concentration and various intermediates from the PPP specifically triggered undecylprodigiosin biosynthesis that required many precursors and NADPH-dependent reduction reaction. This study is the first report on bespoke metabolic engineering of PPP routes especially suitable for producing secondary metabolites that need diverse primary precursors and NADPH, which is useful information for metabolic engineering in Streptomyces.

• Tribology and Lubricants
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• v.17 no.5
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• pp.386-390
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• 2001

Monolayers such as self-assembled monolayer (SAM) have received considerable attention to reduce stiction and friction in micro-devices and microelectromechanical systems (MEMS). Various organic molecular films were investigated to obtain better understanding of their tribological behaviors and adhesion property. The organic molecular films studied in this work are: epoxysilane SAMs, octadecyltricholosilane (OST), multi-layers composed of epoxysilane SAMs, poly[styrene-b-(ethylene-co-butylene)-b-styrene](SEBS) and compound of epoxy resin and poly (paraphenylene)(EP/PPP). The pull-off forces of these films were also obtained from force-distance curves measured in static mode of operation of atomic force microscope(AFM). Tribological tests were conducted with a ball-on-flat reciprocating friction tester. The OST showed the lowest pull-off force, indicating its low adhesion property. It was revealed that, the OST, EP/PPP and the multi-layer of epoxysilane SAMs, SEBS and EP/PPP exhibited good tribological properties at the lower load (0.3 N) whereas the OST showed best performance at the higher load (1.8 N).

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.49-54
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• 2001

Monolayers such as self-assembled monolayer (SAM) have received considerable attention to reduce stiction and friction in micro-devices and microelectromechanical systems (MEMS). Various organic molecular films were investigated to obtain better understanding of their tribological behaviors and adhesion property. The organic molecular films studied in this work are: epoxysilane SAMs, octadecyltricholosilane (OST), multi-layers composed of epoxysilane SAMs, poly〔styrene-b-(ethylene-co-butylene)-b-styrene〕(SEBS) and compound of epoxy resin and poly (paraphenylene) (EP/PPP). The pull-off forces of these films were also obtained from force-distance curves measured in static mode of operation of atomic force microscope (AFM). Tribological tests were conducted with a ball-on-flat reciprocating friction tester. The OST showed the lowest pull-off force, indicating its low adhesion property. It was revealed that, the OST, EP/PPP and the multi-layer of epoxysilane SAMs, SEBS and EP/PPP exhibited good tribological properties at the lower load (0.3 N) whereas the OST showed best performance at the higher load (1.8 N).

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.893-896
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• 2003

Plasma polymerized para-xylene (PPpX) thin films deposited by plasma enhanced chemical vapor deposition (PECVD) were used to passivate the organic light emitting diodes (OLEDs). For OLEDs, indium tin oxide (ITO), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD), tris(8-hydroxyquinoline) aluminum $(Alq_{3})$ and aluminum (Al) were used as the anode, the hole transport layer (HTL), the emitting layer (EML) and the cathode, respectively. The OLED device with the PPpX passivation film (passivated device) showed similar electrical and optical characteristics to those of the OLED device without the PPpX passivation film (control device), indicating that the PECVD process did not degrade the performance of the OLEDs notably. The lifetime of the passivated device was two times longer than that of the control device. Passivation of OLEDs with PPpX films also suppressed the growth of dark spots. The density and size of dark spots of the passivated device were much smaller than those of the control device.

• Journal of Positioning, Navigation, and Timing
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• v.3 no.4
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• pp.155-161
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• 2014

The purpose of this study is to develop precise point positioning (PPP) algorithms based on GLONASS code-pseudorange, verify their performance and present their utility. As the basic correction models of PPP, we applied Inter Frequency Bias (IFB), relativistic effect, satellite antenna phase center offset, and satellite orbit and satellite clock errors, ionospheric errors, and tropospheric errors that must be provided on a real-time basis. The satellite orbit and satellite clock errors provided by Information-Analytical Centre (IAC) are interpolated at each observation epoch by applying the Lagrange polynomial method and linear interpolation method. We applied Global Ionosphere Maps (GIM) provided by International GNSS Service (IGS) for ionospheric errors, and increased the positioning accuracy by applying the true value calculated with GIPSY for tropospheric errors. As a result of testing the developed GLONASS PPP algorithms for four days, the horizontal error was approximately 1.4 ~ 1.5 m and the vertical error was approximately 2.5 ~ 2.8 m, showing that the accuracy is similar to that of GPS PPP.

• Asia-Pacific Journal of Business
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• v.11 no.3
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• pp.21-46
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• 2020

Purpose - This study aims to find if the introduction of project finance perspective leads to any modification to the view of PM industry on CSFs of PPP and their relative importance rank. Design/methodology/approach - Through literature reviews, this study came up with a set of CSFs reflective of both perspectives. AHP method was applied for analysis by developing an Analytic Hierarchical Model from this set and survey questionnaires of pairwise comparison to solicit 46 qualified expert responses. Findings - This study concurs with PM industry to acknowledge 'risk allocation', 'legal framework' and 'quality of feasibility' as ones of most important CSFs. However, relative importance rank of individual CSFs goes through significant modification under this study in favor of 'sponsor commitment and quality' but against 'political environment', in particular. Research implications or Originality - Discussions on the CSFs led by PM industry have not been properly reflective of project finance perspective, which is injected into this study to cure the partiality. For researchers, findings of this study may call attention to financing perspective when they discuss CSFs of PPP. Practitioners may benefit from this study by allocating resources in view of this new finding when pursuing PPP projects.

• Structural Monitoring and Maintenance
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• v.3 no.2
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• pp.145-155
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• 2016

The Pulse-Pre Pump Brillouin Optical Time Domain Analysis (PPP-BOTDA) technique is introduced to implement the multi-direction strain measurement. The monitoring principle is stated. The layout scheme of optical fibers is proposed. The temperature compensation formula and its realizing method are given. The experiments, under tensile load, combined bending and tensile load, are implemented to validate the feasibility of the proposed method. It is shown that the PPP-BOTDA technique can be used to discriminate the multi-direction strains with high spatial resolution and precision.

• KDI Journal of Economic Policy
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• v.41 no.3
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• pp.39-75
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• 2019

An emphasis on public-private partnership (PPP) in the regulatory policy process can overcome the challenges hindering regulatory effectiveness with the emergence of fast developing technologies and new industries. This study attempts to evaluate quantitatively different aspects of institutional settings of South Korean regulatory policy in terms of stakeholder engagement as PPP, using evidence-based data released by the OECD. From the results of the principal component analysis, South Korea can be evaluated as being at a very good level overall in its institutional establishment. Nevertheless, the fact that the outcome of regulatory reforms in South Korea is still insufficient compared with this well-established system suggests that the country should concentrate on improving system operation. Consequently, this study makes policy suggestions to improve regulatory effectiveness through PPP by supplementing the facets that are well-equipped but not feasible with respect to regulatory policy cycle, regulatory governance, regulatory method, and conflict resolution.

• Smart Structures and Systems
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• v.18 no.3
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• pp.405-423
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• 2016

In this study, the feasibility of using telecommunication single-mode optical fiber (SMF) as a distributed fiber optic strain and crack sensor was evaluated in concrete pavement monitoring. Tensile tests on various sensors indicated that the $SMF-28e^+$ fiber revealed linear elastic behavior to rupture at approximately 26 N load and 2.6% strain. Six full-scale concrete panels were prepared and tested under truck and three-point loads to quantify the performance of sensors with pulse pre-pump Brillouin optical time domain analysis (PPP-BOTDA). The sensors were protected by precast mortar from brutal action during concrete casting. Once air-cured for 2 hours after initial setting, half a mortar cylinder of 12 mm in diameter ensured that the protected sensors remained functional during and after concrete casting. The strains measured from PPP-BOTDA with a sensitivity coefficient of $5.43{\times}10^{-5}GHz/{\mu}{\varepsilon}$ were validated locally by commercial fiber Bragg grating (FBG) sensors. Unlike the point FBG sensors, the distributed PPP-BOTDA sensors can be utilized to effectively locate multiple cracks. Depending on their layout, the distributed sensors can provide one- or two-dimensional strain fields in pavement panels. The width of both micro and major cracks can be linearly related to the peak strain directly measured with the distributed fiber optic sensor.