• Elastomers and Composites
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• v.54 no.3
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• pp.201-208
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• 2019

Superabsorbent hydrogel (SAH) is a lightly crosslinked hydrophilic functional polymer material comprising a flexible chain structure, which can absorb and retain high amounts of water or aqueous fluids even under high pressure. Therefore, it is important to improve their characteristics such as absorption performance, residual monomer content, and water permeability. SAH nanocomposites were prepared using clay mineral as an inorganic filler and the influence of post-treatment processes such as quenching and aging process on their properties was studied. In addition, surface-crosslinking process was applied to improve the absorption performance associated with mechanical properties and water permeability. The structure of the SAH was characterized using attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.459-465
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• 1994

Performance of a continuous cocurrent supercritical fluid extraction column for processing of anhydrous milk fat (AMF) was determined. The extract loading increased and the extraction yield decreased as the superficial velocity of AMF increased. The maximum solubility of AMF in $CO_2$ at 4$0^{\circ}C$/3,500 psig was 0.0195g/g. The increase of the carbon dioxide density enhanced the solubility of milk fat and decreased the cholesterol concentration in the extract. Three operation conditions, such as recycle , reflux, and temperature gradient of extraction column, were tested. More short-chain fatty acvids were extracted by the reflux operation . Longchain fatty acids and thehighest ratio fo long-chain unsaturated to saturated fatty acids were also obtained in the raffinate phase with refluex.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.297-302
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• 2016

Water-based systems are dominating the coating market because of worldwide VOCs regulations. Research is focusing especially on waterborne polyurethane (WPU) because of its unique mechanical and chemical properties. However, commercial WPU consists of linear thermoplastic polymers with polar groups on the main chain, which do not perform as well as solvent-borne PU in a two-pack system. In this study, APTES were used as a chain crosslink agent to overcome commercial WPU's limited performance. WPUs synthesized by using a sol-gel process were evaluated with FT-IR, particle analysis, TGA, tensile tests, pull-off tests, SEM, and EIS. The results showed that WPUs with added APTES had better thermal stability, mechanical properties, and water resistance than did WPUs without added APTES. Consequently, the sol-gel process increased the crosslink density of WPUs and modified the WPU's own properties.

• Journal of Korea Technology Innovation Society
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• v.12 no.4
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• pp.840-864
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• 2009

At the time of so-called localization, the start-up and successful management of NTVs (New technology ventures) might be a key factor of regional economic development. The research investigated the factors influencing the performance of NTVs South-western Area. According to the research result, the capability of CEO and R&D cooperation, supply chain integratim, information searching activities, market orientation are the factors which have positive correlation with the performance of NTVs in a statistically significant way in this region.

• Telecommunications review
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• v.25 no.4
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• pp.605-621
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• 2015

The diffusion of smart devices has greatly influenced the market dynamics of the telecommunications industry. The competition paradigm has shifted from individual firm-based competition to ecosystem-based competition. To satisfy the diverse needs of market customers, it has become more important for telecommunications companies to form alliances with complementary partners in the ecosystem. This study empirically investigates the influence of ecosystem-based alliance formations on the financial performance of firms in the Korean telecommunications market. Specifically, the impact of a CPND (Content, Platforms, Networks, and Devices) alliance in the ICT (Information and Communications Technology) sector on firms' profitability is examined using a structural equation model. The results indicate that before the diffusion of smart devices, ecosystem-based alliance formations with other firms in the ICT ecosystem were not effective for enhancing profitability. However, after this diffusion, alliance formation between members of the value chain in the ICT ecosystem contributed significantly to firms' financial performance. This implies that recent alliances with firms that are constituents of the ICT ecosystem are an important element of profit generation in the ICT market in Korea.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.630-639
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• 2004

The Stewart platform manipulator is a closed-kinematics chain robot manipulator that is capable of providing high structural rigidity and positional accuracy. However, this is a complex and nonlinear system, so the control performance of the system is not so good. In this paper, a new robust motion control algorithm is proposed. The algorithm uses partial state feedback for a class of nonlinear systems with modeling uncertainties and external disturbances. The major contribution is the design of a robust observer for the state and the perturbation of the Stewart platform, which is combined with a variable structure controller (VSC). The combination of controller and observer provides the robust routine called sliding mode control with sliding perturbation observe. (SMCSPO). The optimal gains of SMCSPO, which is determined by nominal eigenvalues, are easily obtained by genetic algorithm. The proposed fitness function that evaluates the gain optimization is to put sliding function. The control performance of the proposed algorithm is evaluated by the simulation and experiment to apply to the Stewart platform. The results showed high accuracy and good performance.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.1 s.160
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• pp.95-106
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• 2007

The purpose of this study is to investigate the relationship between the implementation and the performance of the eSCM in internet shopping malls, and to suggest collaborated strategy for internet shopping malls. We performed the surveys of suppliers for 3 fashion-specialized internet shopping malls and 3 general internet shopping mall. Additional surveys was performed by surveying the shopping mall merchandisers to research the differences of understandings on the performance of the eSCM between shopping malls and their suppliers. Total 143 questionnaries were distributed and collected from January 23 to February 28, 2006 and analyzed by SPSS 10.0. The results are as follows; 1) the efficiency of eSCM is related the factors of partnership and information, and among the subordinated factors the understanding and support of the top management, good communications, product and operating information sharing were find out to be significant. 2) The effectiveness of eSCM is influenced by the organizational and partnership factor. As the subordinated factors, the understanding and supports of the top management, the participations of members, good communications, good relationship and supports, and the technology level of eSCM were identified as significant. 3) Examining the differences of understandings on the performance of eSCM between the suppliers and the shopping mall merchandisers, the suppliers and the merchandisers show different opinions on the operating efficiency, and the customer service.

• The Journal of Society for e-Business Studies
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• v.24 no.3
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• pp.1-18
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• 2019

Due to the great advances in e-Marketplace and changes in type of items purchased from the online market, it has been dramatically increased the demand of the storage and transportation under the special conditions such as restricted temperature. Especially, the cold chain needs the way to transparently measure and monitor the entire network in realtime because it has a very complicated structure and requires totally different criteria at the every different steps and items. In this research, it has been presented the performance evaluation metrics to make contract using service level agreement (SLA), the way to apply the smart contract based on blockchain, the structure of blocks, service platform and application in order to build cold chain which can prevent the risk factors by measuring and sharing information in realtime using block chain technology. In addition, we have proposed the way to store the measured performance and reputation of each player in the block using smart contract based on SLA. With the presented framework, all players including service providers as well as users can secure the information for making the rational decisions. When the service platform is actually built and operated, it seems possible to secure the information in transparently and realtime. Also, it is possible to prevent the risk factors or prepare the preemptive plans to react on them.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.1
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• pp.117-124
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• 2020

3D printing is a technology that has significantly grown in recent years, particularly in the aerospace, defense, and medical sectors where it offers significant potential cost savings and reduction of the supply chain by allowing parts to be manufactured on-site rather than at a distance supplier. In nuclear industry, 3D printing technology should be applied according to the manufacturing trend change. For the application of 3D printing technology to the nuclear power plant, several problems, including the absence of code & standards of materials, processes and testing & inspection methods etc, should be solved. Preemptively, the improvement of reliability of 3D printing technology, including mechanical properties, structural performance, service performance and aging degradation of 3D printed parts should be supported. These results can be achieved by collaboration of many organizations such as institute, 3D printer manufacturer, metal powder supplier, nuclear part manufacturer, standard developing organization, and nuclear utility.

• Journal of Distribution Science
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• v.22 no.4
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• pp.23-35
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• 2024

This study investigates the organizational factors including firm size, adaptive capability, absorptive capability, innovative capability, and executive support to determine internet of things, production and services, and organizational performance. Research design, data, and methodology: A quantitative methodology was employed, involving the distribution of surveys to 460 employees occupying managerial and strategic roles. These individuals have accrued a minimum of one year of experience within 20 leading manufacturing and distribution companies in Thailand, each boasting a workforce exceeding 250 employees. Sampling techniques utilized encompass judgmental, quota, and snowball sampling. Furthermore, analysis of the data was conducted through Confirmatory Factor Analysis (CFA) and Structural Equation Model (SEM). Results: The findings indicate that factors such as firm size, adaptive capability, absorptive capability, and innovative capability exert significant influence on the Internet of Things (IoT). In addition, IoT significantly impacts both production and services. Furthermore, the study highlights the significant influence of production and services on organizational performance. However, the anticipated relationship between executive support and IoT lacks support according to the results. Conclusions: This study highlights the transformative potential of IoT for the manufacturing and distribution sector, paving the way for enhanced efficiency, competitiveness, and sustainability in a rapidly evolving business landscape.