• Macromolecular Research
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• v.14 no.3
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• pp.338-342
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• 2006

The kinetic features of polymerization with an active site comprising cobalt dihalides ($CoX_2$, where X=Cl, Br, I) activated by methylaluminoxane (MAO) were investigated in 1,3-butadiene polymerization. The catalytic system exhibited the characteristic features of living polymerization. The initiation ($k_i$) and propagation ($k_p$) rate coefficients were estimated using the kinetic model for slow initiation previously reported by Shiono et al. The energy of activation fur the propagation reaction was calculated to be 27-30 $kJmol^{-1}$. The marked changes in reaction rate observed with different halides could be adequately described in terms of variations in the initiation process, with the same Arrhenius curve fitting propagation rate coeffcients estimated from all three halides, suggesting that the halide does not participate in the growing chain end.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.3
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• pp.121-132
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• 2005

Nowadays, Information Technology(IT) has become one of the most critical managerial decision areas, because its role in the business practice tends to be more important and hence the amount of the investment in growing. Since there is no dominant and promising measure to evaluate the IT performance, the managements have difficulties on the decision process for IT investment. In this paper, we propose an IT performance evaluation model. The proposed model starts with finding the business performance evaluation areas and the corresponding KPIs, and then concentrates on the IT performance evaluation areas corresponding to the business performance evaluation areas. To extract the specific and reliable KPIs for the IT performance measure, we map the business performance evaluation areas into the corresponding IT performance evaluation areas and then combine and adjust these KPIs with the KPIs obtained from the experiential field interview. Finally, We present the complete model which has 11 business performance indices and 48 IT performance indices are completed.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.4.2-4
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• 1981

The auther experienced a case of difficult decannulation in a 52-day-old male infant, in which decannulation was performed at one and half years after tracheostomy. Tracheostomy was performed for the maintenance of airway due to severe dyspnea, cyanosis, retraction of suprasternal notch and epigastrium during the inspiration with acute laryngotracheobronchitis. The patient became gradually adjusted to the continual cannula corking training along with growing process over the period of 18 months.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.709-715
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• 1999

Polyphenol oxidase (PPO) activity in 200×g (cell wall), 4,000×g (plastid), 100,000×g (mitochondrial) and soluble fractions of the perilla leaves was monitored in the upper, middle and lower sections of the plant. In the course of plant growth, PPO activities in plastid and mitochondrial fractions were decreased, while those in cell wall fraction were maintained. During growing process, specific activities and PPO activities of each fraction were decreased, while total phenol content were decreased in middle (middle) and then increased in later stage (lower). Cell wall, plastid, mitochondrial (pellet) and soluble fraction had slightly different pH optima and substrate specificities. Isoenzyme patterns were identical in two bands for PPO activity in different subcellular fractions. Their molecular weights were 37KD and 48KD respectively.

• KSBB Journal
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• v.13 no.4
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• pp.461-467
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• 1998

A fermentation system was supplemented with a device for the measurement of the durations of alkali pump feeding for automatic pH control and an A/D convertor for precise monitoring of pH value by computer. A software program was developed to measure buffer capacities from the pH signal and the pH control signal during fermentation. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed correlation to those of estimated by the software sensor. Lacitic acid production was also successfully estimated by the values of buffer capacities measured on-line.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.2
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• pp.108-112
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• 2012

A sustainable production of electricity is essential for low carbon green growth in South Korea. The generation of wind power as renewable energy has been rapidly growing around the world. Undoubtedly wind energy is unlimited in potential. However, due to its own intermittency and volatility, there are difficulties in the effective harvesting of wind energy and the integration of wind power into the current electric power grid. To cope with this, many works have been done for wind speed and power forecasting. It is reported that, compared with physical persistent models, statistical techniques and computational methods are more useful for short-term forecasting of wind power. Among them, support vector regression (SVR) has much attention in the literature. This paper proposes an SVR based wind speed forecasting. To improve the forecasting accuracy, a fuzzy clustering is adopted in the process of SVR modeling. An illustrative example is also given by using real-world wind farm dataset. According to the experimental results, it is shown that the proposed method provides better forecasts of wind power.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.225-226
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• 2017

Recently, there has been a growing interest in the development of non-sintered binder to reduce CO2 emissions from the cement clinker manufacturing process and a number of studies have been conducted on fly ashes as an industrial by-product. However, in order to utilize fly ashes as a non-sintered binder, it is necessary to solve problems such as safety issues and economical efficiency due to use of an alkali activator. This study evaluates the material properties and compressive strength characteristics of three types of circulating fluidized bed boiler ashes. As a result, it was confirmed that the characteristics of each binder vary depending on the location of the power plant and the types of raw materials. In addition, it has been confirmed that the fluidized bed boiler ash shows a high compressive strength and can be used sufficiently as an non-sintered binder.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2588-2590
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• 2001

Distribution ayatems at the final stage of the power supply process are directly and extensively connected to customers. There are growing demands for more efficient operation and higher reliability. This paper describes the embodiment of distribution automation using internet networks. We suggest the large region distribution server system for distribution automation functions in local area network, automated meter reading system and directed load control system with by-directional communication.

• Industrial Engineering and Management Systems
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• v.9 no.4
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• pp.303-311
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• 2010

In the last few years growing interest has been dedicated to supply chain management. Modeling complexity is added to supply chain coordination problem by accounting for reverse logistics activities. The objective of this paper is to extend inventory model of manufacturing factory with respect to the production of raw material of forward logistics and recycling material of reverse logistics. The proposed model is applied to a plastic recycling process plant located in Taiwan. The case study improvement scheme shows when the recycling rate of recycling material increases from 15% to 50%, the total inventory cost of manufacturing factory decreases by 12.82%, safety stock volume decreases by 41.19% and the reorder quantity is down by 50.96%. This paper finds whether the results of the model can reach the economic profit through quantitative analysis and encourages companies integrate reverse logistics into the supply chain system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.210-212
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• 2011

Human Computer Interaction is rapidly growing in different aspects and areas. One of the areas that grab many scholars and researchers interest is usability. Usability is a main factor and critical pillar of products success and acceptance. In this paper, we deeply analyze the current usability models that measure the user performance during the interaction with products. Then, we fairly compare between each model to discover and present the strength and weakness of each model for supporting developer and business organization with guidelines during the development process of the products before launching the actual and final one. Decomposing comparison between each model is performed based on specific criteria. Comparison is tabulated, graphically depicted, and analytically decomposed.