• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.5-18
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• 2016

Electron microscopy is an important investigation and analytical method for the morphological characterization of various cellulosic materials, such as micro-crystalline cellulose (MCC), microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC), and cellulose nanocrystals (CNC). However, more accurate morphological analysis requires high-quality micrographs acquired from the proper use of an electron microscope and associated sample preparation methods. Understanding the interaction of electron and matter as well as the importance of sample preparation methods, including drying and staining methods, enables the production of high quality images with adequate information on the nanocellulosic materials. This paper provides a brief overview of the micro and nano structural analysis of cellulose, as investigated using transmission and scanning electron microscopy.

• Journal of the Korean Society for information Management
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• v.30 no.1
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• pp.111-129
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• 2013

This study analyzed the process of multimedia services and indexed the core quality characteristics through the tools employed in 'Define' and 'Measure' steps of the 6 Sigma DMAIC methodology. To achieve the goal, as a case study of 'S' University Central Library, first, brainstorming technique was used to tap the librarians, second, interview with the half-time student workers, third, user's opinion on homepage was analyzed and lastly, the interview with the users. This study also drew some potential causal factors which would likely to affect the multimedia service using Process Map and C&E Diagram. Those factors were prioritized using X-Y matrix and Pareto Chart. This study revealed 14 factors affecting multimedia services: 'presence/absence of the persons who are in charge of selection', 'cycle of selection materials', 'presence/absence of seperated multimedia room', 'materials arrangement method', 'notification of popular materials', 'notification of documents arrivals', 'methods of noticing new arrivals', 'methods of ordering materials', 'cycle of checking order status', 'types of persons requesting materials', 'methods of requesting materials', 'checking of the status of the returned materials', 'methods of noticing materials in housed', and 'methods of ways to return overdue materials'.

• Carbon letters
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• v.13 no.1
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• pp.23-28
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• 2012

Graphene is an attractive material for device applications, but device characteristics are very unstable because the graphene is very sensitive to environmental factors such as charges nearby the graphene, metal contacts, defects, contaminants and other adsorbates. Since the interactions between graphene and environmental factors affect the electrical characteristics of graphene devices, the interpretation of electrical characteristics as simple as current-voltage curves is non-trivial, despite the common practice of using well known electrical characterization methods that have been used in silicon MOSFET. This paper addresses major obstacles in the electrical characterization of graphene devices and offers countermeasures to improve the accuracy of electrical characterization methods.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.141-148
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• 2009

The purpose of this paper is to propose a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. Green roof system is considered to be an important subject in construction industry for green growth project. At the same time, we have to consider the counterplan for protection the damage of waterproofing layer and concrete substrate from the penetration of plant root. But many kinds of materials for protection from root penetration are using in construction field. But the performance of those materials is not clear, and there is not test methods for the evaluation of performance. So in this paper, based on the research results of 4 institutes during four years and foreign cases, we made a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. This test method deals with about environmental condition of laboratory, experimental facilities, kinds of plant, specimen of test, management methods, evaluation duration and documents, etc.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.569-575
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• 2017

One of the important requirements for the application of reduced-activation ferritic/martensitic (RAFM) steel is to retain proper mechanical properties under irradiation and high-temperature conditions. To simulate the yield strength and stress-strain curve of steels during high-temperature and irradiation conditions, a multiscale simulation method consisting of both microstructure and strengthening simulations was established. The simulation results of microstructure parameters were added to a superposition strengthening model, which consisted of constitutive models of different strengthening methods. Based on the simulation results, the strength contribution for different strengthening methods at both room temperature and high-temperature conditions was analyzed. The simulation results of the yield strength in irradiation and high-temperature conditions were mainly consistent with the experimental results. The optimal application field of this multiscale model was 9Cr series (7-9 wt.%Cr) RAFM steels in a condition characterized by 0.1-5 dpa (or 0 dpa) and a temperature range of $25-500^{\circ}C$.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.125-128
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• 2005

Recently new materials, such as fiber reinforced polymer(FRP) and other composite materials are being applied in reinforcing plate or plate or prestressing cables of concrete structures. Although these new materials themselves show the excellent durability and high strength, the bond behaviour between concrete surface and FRP is not well recognized. Therefore, this paper propose a evaluation method for effective bond length between fiber reinforced polymer(FRP) and concrete. To develop the evaluation method, this paper presents a review of current evaluation methods for effective bond length. These methods are compared by single face test, expose merits and demerits. And based on them, new evaluation method was developed. Finally, the new method was compared with existing methods to verify a adequateness for evaluation of effective bond length.

• Applied Science and Convergence Technology
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• v.26 no.5
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• pp.95-109
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• 2017

There are several contributions to the gas load of a system of which often the most important is outgassing. Adsorption occurs via two main processes, physisorption and chemisorption, and can be described using five (or six) classifying isotherms. Outgassing is the result of desorption of previously adsorbed molecules, bulk diffusion, permeation and vapourisation. Looking at the desorption rate, pumping speed and readsorption on surfaces, the net outgassing of the system can be calculated. There is significant variation in measured outgassing rates between different materials but also between published rates for the same materials, in part due to the number of different methods used to measure outgassing. This article aims to review the outgassing process, outgassing rates, measurement methods and techniques that can be used to reduce the outgassing of a system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.107-111
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• 2003

The need for this study must be considerable, as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover. it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction. which have enormously large impact on the durability.

• Korean Journal of Construction Engineering and Management
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• v.14 no.3
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• pp.107-114
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• 2013

The interest in traditional Korean housing has greatly increasing in Korean housing market. However, it is difficult to wildly disseminate for a high construction cost reason. In order to effectively facilitate the Hanok construction, Korean government has initiated a project that develops a new style Korean housing, which meets the requirements of low cost and modernized life style. Cost of building is mainly affected by materials and construction methods. Hanok has some special commodities those significantly impact the cost. In order to effectively cut down the costs, well-organized planning for costs is very important. Also, improving the productivity by utilizing new materials and methods can result in cost down. In this context, this paper compared and analyzed two different types of Korean housing; one is a modernized Korean house which used new materials and methods, the other is a traditional Korean house which was build up by purely traditional methods. Productivity has also been compared and analyzed for 5 major commodities between two types of models. Based on these comparative data, effect of cost down by new model has been analyzed. As a result it is confirmed that by using the new materials and methods could highly effect to increasing productivity and cost down. Especially, the cost of Roofing have been more influenced by using new material while the Wood and Finishes have been influenced by new construction method. Construction cost of Foundation (Earthwork, Concrete, Masonry) and Openings were influenced both factors, changing of materials and methods.

• Journal of the Korean Ceramic Society
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• v.55 no.3
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• pp.185-202
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• 2018

Photoelectrochemical (PEC) cells can convert solar energy, the largest potential source of renewable energy, into hydrogen fuel which can be stored, transported, and used on demand. In terms of cost competitiveness compared with fossil fuels, however, both photocatalytic efficiency and cost-effectiveness must be achieved simultaneously. Improvement of cost-effective, scalable, versatile, and eco-friendly fabrication methods has emerged as an urgent mission for PEC cells, and solution-based fabrication methods could be capable of meeting these demands. Herein, we review recent challenges for various nanostructured oxide photoelectrodes fabricated by solution-based processes. Hematite, tungsten oxide, bismuth vanadate, titanium oxide, and copper oxides are the main oxides focused on, and various strategies have been attempted with respect to these photocatalyst materials. The effects of nanostructuring, heterojunctions, and co-catalyst loading on the surface are discussed. Our review introduces notable solution-based processes for water splitting photoelectrodes and gives an outlook on eco-friendly and cost-effective approaches to solar fuel generation and innovative artificial photosynthesis technologies.