• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.188-191
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• 2002

A glucan and a fructan producing enzymes from Leuconostoc mesenteroides NRRL B-1149 were prepared and concentrated from the cu1ture of 1.5% sucrose using polysulfone ultrafiltration hollow fiber in the presence of 0.1% (w/v) Tween 80, 1 mM $CaCl_2$, and 0.02% $NaN_3$. The molecular masses of the enzymes were estimated to be about 213.6 kDa and 180 kDa, respectively, based on the PAS staining for the glucosyltransferase and Mukasa method for fructosyltransferase. Polymers produced by the enzymes showed different solubility; an insoluble glucan and a soluble fructan. The linkages of polymers were determined by methylation using Hakomori reagent and following acid hydrolysis. The glucan was composed of ${\alpha}$-1,6 and 1,3 linkages and the fructan showed similar linkage data of levan.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.4
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• pp.59-67
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• 2003

This paper presents a new approach for the use of smart materials, piezoelectric materials of PVDF and PZT, for vibration attenuation of a planar parallel manipulator. Since lightweight linkages of parallel manipulators deform under high acceleration/deceleration, an active damper is needed to attenuate vibration due to structural flexibility of linkages. Based on the dynamic model of a planar parallel manipulator, an active damping controller is developed, which consists of a PD feedback control scheme, applied to linear electrical motors, and a linear velocity feedback (L-type) scheme applied to either PVDF layer or PZT actuator(5). Simulation results show that piezoelectric materials yield good damping performance, resulting in precise manipulations of a planar parallel manipulator.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.303-313
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• 2005

Agricultural environmental indicators (AEIs) are useful tool for evaluating environmental performance induced by agri-environmental policy measures. General and specific criteria have been set to assess the linkages between policy measures and environmental states. In addition, a number of specific AEIs such as nutrient balance indicators and farm management indicators have been posit to review environmental performance associated with agri-environmental policy measures. The proposed environmental subjects encompass soil quality, qualities of underground and surface water, water resource preservation, species and genetic diversity, diversity for wildlife habitats, and agricultural landscapes. The developed AEIs may contribute to establishment or adjustment of environmental targets and ex-ante or ex-post evaluation for environmental performance associated with policy measures. In addition, the AEIs may be useful to consider introduction of new agri-environmental measures and enhance policy efficiency by assessing environmental performance, considering specific locality, and harmonizing support measures.

• Journal of the Korea Society of Computer and Information
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• v.20 no.6
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• pp.151-159
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• 2015

In traditional programing education, computers were used as the main tool. Consequently, it was problematic to provide education in an environment without computers or for learners without computer skills. To address this problem, this study developed and validated an unplugged robot education system capable of computerless programming education. The key feature of the proposed system is that programing can be done only by connecting programming blocks in symbols of a flow chart with built-in commands. Validation of the system was performed by a specialist group. Validity was very high with values of content validity ratio (CVR) over 0.7 in all evaluation criteria except "Ease of error debugging" and "Linkages to educational curriculum," whose CVR values were each 0.6. Future directions include improvement in the two areas that scored lower than the others did by, respectively, system improvement to support debugging in error conditions that may occur during the programming process, and development of user guide to support linkages to educational curriculum.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.248-254
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• 2012

During the monolayer assembly of zeolite microcrystals using sonication with stacking (SS) method, the factors that govern the degree of close packing (DCP) between the microcrystals, the rate of attachment (rA) of microcrystals onto the substrate, the degree of coverage (DOC), and the binding strength (BS) between each crystal and the substrate were investigated for each mode of binding linkage (MBL). The tested MBLs were covalent linkage (CL), ionic linkage (IL), and polyelectrolyte-mediated ionic linkage (p-IL). Unlike the monolayers of zeolite crystals assembled on glass with a covalent linkage, the strong BS, very high DOC, and very high DCP do not decrease during monolayer assembly on glass through ionic linkages. This results indicate that the surface migration of crystals undergo linkage-nondestructively when crystals were attached to the substrates through ionic linkages.

• Journal of Korea Technology Innovation Society
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• v.6 no.2
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• pp.228-252
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• 2003

This research has been focused upon and analyzing Medison, once a leading New Technology-Based Finn (N1BF) in Korea with exceptionally advanced technology in 3D ultrasound diagnostic imaging devices (UDIDs) (armored with 23 subsidiaries at its peak expansion), from the perspective of Dynamic Finn Capability(DFC). The underlying hypothesis is that the various problems from its pointless pursuit of the business styles or precedents of the existing large firms might be traced to its specific characteristics as an NTBF, which should have more preferably been based upon the distinctive competences such as differentiated technologies, institutional linkages, organizational routines, and complementary assets, etc. In conclusion, for the NTBFs with different DFC domains from those of the large firms, the optimal external linkages and comprehensive integration efforts (Process) under their specific organizational characteristics and constraints (path) are highly recommended for the continuous accumulation of their core capabilities based upon the technological assets (Position).

• East Asian Economic Review
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• v.24 no.2
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• pp.185-203
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• 2020

This paper investigates the connectedness among housing markets using the methodology developed in Diebold and Yilmaz (2014, 2016). In particular, we examine the international linkages among housing markets in Northeast Asian countries: namely, China, Japan, and Korea. The basic finding is that connectedness measures vary over the business cycle, with a surge during the global financial crisis. However, the international linkages among the three Asian housing markets seem rather weak. By including GDP in the model, we also find that housing market in one country is more affected by its own economic conditions than that of neighboring countries. Given earlier evidence that cross-regional spillover among domestic housing markets is high, this result suggests that housing market connectedness is more of domestic cross-regional phenomena, rather than international ones.

• Proceedings of the Technology Innovation Conference
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• 1993.11a
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• pp.119-147
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• 1993

This paper explores the relationships between technological acquisition strategies of small firms and innovation in the Korean Electronics industry. Its thesis is that small firms' technology strategies and their effects on the rate of innovation differ according to the new and traditional technology settings. A primary finding of this study is that in-house R & D and technical linkages with buyers and suppliers have stronger effects on the radical innovation in the new technology setting rather than in the traditional technology setting. The findings of the study provides insight for interpreting inconsistent results of recent research for the importance of external linkages to innovation. They also suggest some implications of small firms' strategies and public policies for accelerating technological innovation.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.912-916
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• 2018

Crawling robots are advantageous in overcoming obstacles. These robots have characteristics such as light weight and outstanding mobility. In case of large robots, they have difficulties passing narrow gaps or entering the cave. In this paper, we propose a milli-scale hexapedal robot using 4-bar linkages. Two conditions are necessary to enable efficient walking. In short, the trajectory of the foot must be elliptical, and the lowest point of the foot should be the same. These conditions are satisfied with a novel leg design. The robot has a pair of three legs and the legs are coupled to operate simultaneously. Each set of the legs are installed to robot's both sides and the legs satisfy the equal lowest foot point and elliptical trajectory. As a result, this hexapedal robot can crawl with 0.56m/s speed.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.3
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• pp.437-456
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• 2016

The purpose of this study is to understand the locational characteristics of performing art industries and to investigate the linkages with local economy. For the purpose, we examine the spatial concentration of cultural and artistic resources in Korea first, and than focus on Seoul where the resources of performing art industries are concentrated to the utmost. To distinguish the distribution aspect and locational characteristics of performing art industries, we apply the Kernel density analysis and LISA (Local Indicator of Spatial Association) on the address data of performing art theater, gallery, and movie theater. In contrast to galleries and movie theaters. the spatial distribution pattern of performing art theaters reveals a unique local cluster centered on the Daehakro area. We confirm that the Daehakro area constitutes a performing art industry cluster in their dense distribution of various related activities making up the value chain of the performing art industry. Multiple regression analysis probes the related economic activities to explain the distribution of performing art theaters as well as the linkages with the local economic landscape.