• Computers and Concrete
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• v.19 no.6
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• pp.737-744
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• 2017

Geopolymer Concrete is typically proportioned with activator solution leading to moderately high material cost. Such cost can be enduring in high value added applications especially when cost savings can be recognized in terms of reduction in size of the members. Proper material selection and mix proportioning can diminish the material cost. In the present investigation, a total of 27 mixes were arrived considering the mix parameters as liquid-binder ratio, slag content and sodium hydroxide concentration to study the mechanical properties of geopolymer concrete (GPC) mixes such as compressive strength, split tensile strength and flexural strength. The derived statistical Response Surface Methodology is beleaguered to develop cost effective GPC mixes. The estimated responses are not likely to contrast in linear mode with selected variables; a plan was selected to enable the model of any response in a quadratic manner. The results reveals that a fair correlation between the experimental and the predicted strengths.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.351.1-351.1
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• 2016

While conventional electronic devices have been fabricated on the rigid and brittle Si based wafer as a semiconducting substrate, future devices are increasingly finding applications where flexibility and stretchability are further integrated to enable emerging and wearable devices. To achieve high flexibility and stretchability, various approaches are investigated such as polymer based conducting composite, thin metal films on the polymer substrate, and structural modifications for stretchable electronics. In spite of many efforts, it is still a challenge to identify a solution that offers both high stretchability and superior electrical properties. In this paper, we introduce a highly stretchable entangled-mesh graphene showing a potential to address such requirements as stretchability and good electrical performance. Entangle-mesh graphene was synthesized by CVD graphene on the Cu foil. To analyze the mechanical properties of entangled-mesh graphene, endurance and stretching tester have been used.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.9
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• pp.693-698
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• 2016

A decentralized control method is proposed to enable a group of robots to achieve maximum performance in multisensory target tracking while avoiding collision with the target. The decentralized control was designed based on navigation function formalism. The study showed that the multiple agent system converged to the positions providing the maximum performance by the decentralized controller, based on Lyapunov and Hessian theory. An exemplary simulation was given for a multiple agent system tracking a stationary target.

• ETRI Journal
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• v.37 no.1
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• pp.11-20
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• 2015

This paper deals with optimal power allocation for channel estimation of orthogonal frequency-division multiplexing uplinks in time-varying channels. In the existing literature, the estimation of time-varying channel response in an uplink environment can be accomplished by estimating the corresponding channel parameters. Accordingly, the optimal power allocation studied in the literature has been in terms of minimizing the mean square error of the channel estimation. However, the final goal for channel estimation is to enable the application of coherent detection, which usually means high spectral efficiency. Therefore, it is more meaningful to optimize the power allocation in terms of capacity. In this paper, we investigate capacity with imperfect channel estimation. By exploiting the derived capacity expression, an optimal power allocation strategy is developed. With this developed power allocation strategy, improved performance can be observed, as demonstrated by the numerical results.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.104-112
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• 1999

Since the anaerobic rumen fungi were discovered in the rumen of a sheep over two decades ago, they have been reported in a wide range of herbivores fud on high fibre diets. The extensive colonisation and degradation of fibrous plant tissues by the fungi suggest that they have a role in fibre digestion. All rumen fungi studied so far are fibrolytic. They produce a range of hydrolytic enzymes, which include the cellulases, hemicellulases, pectinases and phenolic acid esterases, to enable them to invade and degrade the lignocellulosic plant tissues. Although rumen fungi may not seem to be essential to general rumen function since they may be absent in animals fed on low fibre diets, they, nevertheless, could contribute to the digestion of high-fibre poor-quality forages.

• Journal of Korean Society for Quality Management
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• v.23 no.1
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• pp.1-14
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• 1995

ISO 3951 (1989) Sampling Procedures and Charts for Inspection by Variables for Percent Nonconforming is an acceptable quality level (AQL) type sampling scheme. Sample size code letters and inspection levels in this International Standard correspond to those given in the ISO 2859 (1989), a standard for sampling plans by attributes. Two acceptance sampling procedures can be used ; tabular and graphical methods. The graphs could be used in less critical applications while the tabular method would be available for those familiar with MIL-STD-414 tables and to confirm the results of the graphs when needed. The sampling procedures of the ISO 3951 are matched to the ISO 2859 to enable us to move between them. Composite OC and ASN curves are given for AQL 2.5% and code letter F.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.3
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• pp.133-140
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• 2015

Neural stimulating implantable medical devices (IMDs) have been widely used to treat neurological diseases or interface with sensory feedback for amputees or patients suffering from severe paralysis. More recent IMDs, such as retinal implants or brain-computer interfaces, demand higher performance to enable sophisticated therapies, while consuming power at higher orders of magnitude to handle more functions on a larger scale at higher rates, which limits the ability to supply the IMDs with primary batteries. Inductive power transmission across the skin is a viable solution to power up an IMD, while it demands high power efficiencies at every power delivery stage for safe and effective stimulation without increasing the surrounding tissue's temperature. This paper reviews various wireless neural stimulating systems and their power management techniques to maximize IMD power efficiency. We also explore both wireless electrical and optical stimulation mechanisms and their power requirements in implantable neural interface applications.

• Journal of Korea Multimedia Society
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• v.21 no.2
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• pp.310-322
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• 2018

Documentation is a typical method that helps students to understand a program for implementation and execute error correction and maintenance cost-effectively. Guidelines for components that organize documentation should be provided to enable to express computational thinking and such components also should be linked to coding process. In this paper, we focused on the documentation format to guide elementary school students, who were beginners in computational thinking, to express computational thinking. The improvement in the expression of computational thinking was analyzed based on the documentation format applied to the class, and practical tips on the importance of components organizing the documentation format were proposed.

• Journal of Power Electronics
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• v.15 no.5
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• pp.1295-1304
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• 2015

In this paper, an approach to extend the life of lead-acid batteries through the elimination of sulfation with "rest time" using the pulse current of a conventional DPV (Differential Pulse Voltammetry) method is discussed. A new rest time without "0" current in "saw-tooth" pattern pulses is proposed to overcome the "0" current (blackout period), which is a shortcoming of DPV. This will enable the proposed method to be used in the loaded state. In the proposed approach, ESSs (Energy Storage Systems) were discharged for 5 h twice per day for 6 months on weekdays. To observe the changes in the lifespan of the systems, for the same period, the changes in the impedances of lead-acid batteries which were being charged e without charging and discharging were measure and compared. This study is focused on determining the effectiveness of lead-acid batteries as ESSs.

• Journal of Information Technology Services
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• v.18 no.5
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• pp.193-207
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• 2019

In recent years, Digital Social Innovation has been emerging at home and abroad and new solutions are being proposed by the perspective of User using digital technology in order to solve social and economic problems of the city. In addition, Living Labs which is an innovative tools and space enable to solve problems doing activities with various participants led by users. Therefore, this study aims to systematically manage the activities of Living Lab in Digital Social Innovation and improves the Living Lab sustainability using the performance indicators which are going to be developed. Furthermore, construct the appropriate indicator of each project process and take test at real Living Labs. As a result, performance indicator was derived from each procedure in the Living Lab project, and proved validity and reliability of the indicators through qualitative and quantitative methods by interviews and the questionnaire from the participants of Living Labs.