• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.2
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• pp.18-26
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• 2012

Though electricity consumption amount in industry has been increased gradually, corresponding power supply show symptoms of marginal point. Importance of demand-side management from large-industries has also been raised. This paper deals with induction motor, which is one of representative examples of heavy electricity consumption utilities, to analyze potential technical capability, economic feasibility from consumers' viewpoint and demand-side management feasibility from nation-wide perspective. Nation-wide economic feasibility analysis was done through California test, which has been used as demand-side management evaluation model. This paper also describes limitation of existing high efficiency induction motor in terms of contribution to demand-side management and utilizes premium motor to calculate demand-side management contribution level and economic feasibility evaluation. Likewise, this paper emphasizes the efficiency improvement of induction motor and analyzes how much premium motor related technologies can contribute to demand-side management.

• Membrane and Water Treatment
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• v.9 no.1
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• pp.33-42
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• 2018

Microscopic examination of the activated sludge and morphological characterization of the flocs provides detailed information about the treatment process. The aim of this study is to investigate the morphological parameters of flocs obtained from a thermophilic jet loop membrane bioreactor (JLMBR) in different sludge retention times (SRTs), considering EPS and SMP concentration, hydrophobicity, zeta potential. The results showed that irregularity decreased with the increasing SRT. The compactness value was calculated to be less than 1 for all SRTs. However, the sludge had a more compact structure when the SRT increased. Zeta potential increased whereas hydrophobicity and floc size reduced, with increasing SRT. Furthermore, 2-D porosity calculated using the hole ratio was higher at greater SRTs. Hence, there was a significant correlation between the results obtained using the imaging technique and operation conditions of thermophilic JLMBR.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.4
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• pp.67-75
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• 2011

Sulfuric acid hydrolysis is a typical approach for producing cellulose nanocrystals. The method has been widely used, but it has a disadvantage of low yield of cellulose nanocrystals compared to mechanical method. To expand the application of cellulose nanocrystals in practical, we should be able to produce them with higher yield and the controlled properties. In this study, therefore, we intended to investigate the effect of sulfuric acid hydrolysis condition on the characteristics of the prepared cellulose nanocrystals. The concentration of sulfuric acid, temperature and hydrolysis time were varied, and the yield as well as diverse properties including the morphology, size and zeta potential were examined. We could obtain cellulose nanocrystals up to 70% of yield and found that the properties were dependent on the reaction condition. It would be helpful to select an appropriate condition for producing cellulose nanocrystals.

• Journal of Forest and Environmental Science
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• v.32 no.4
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• pp.392-399
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• 2016

This review paper presents guidelines which stakeholders use in addressing on-farm tree planting configuration, establishment, tending, silvi- cultural management, management of pests and diseases, challenges and opportunities as practiced in the medium to high potential areas of Kenya. The tree planting configurations discussed includes blocks planting (woodlot), boundary, compound planting, home/fruit gardens, trees intercropped or mixed with pasture, trees on riverbanks and roadside. Participatory monitoring and evaluation techniques have been highlighted. The main challenges facing tree planting activities include culture and attitude of local people, land and tree tenure, inadequate technical support, lack of recognition and integration of technical information and indigenous knowledge, capital and labour shortages, lack of appropriate incentives measures, damage by domestic and wild animals, conflict over trees on the boundary and policy and legal issues. This guideline targets forest managers, extension agents, students and other practitioners in policy and day to day decision making processes in Kenya.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.1
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• pp.1-7
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• 2014

The current downturn of BIPV sector has an enormous potential to rebound and expand into the PV sector for construction market in the foreseeable future. Solar technology has already gained a significant market due to lack of natural resources in the Korean domestic market. Given the technical infrastructure of state-of-the-art fusion technology, the competitiveness of software-driven BIPV market in the world can be ver attractive and have the potential to develop as a key national technology. To do this, from the viewpoint of complexity, technical R&D, national political aspect, social aspect, economic aspect and institutional support systems need to be parallelly formulated. A dedicated BIPV sector has not yet been established, especially policy and institutional framework have very crucial impact on the establishment of BIPV sector.

• Journal of the Korea Safety Management & Science
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• v.18 no.2
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• pp.29-36
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• 2016

This study of small & Medium-Sized construction sites construction disaster prevention technology conduction-site visits from the map results report by the inspector on-site advice and technical guidance for the analysis of deficiencies and potential construction of disaster revealed the potential factors causing an accident as follows. As a results, Should not be a once a month visits. Therefore should be changed at least twice a month to help prevent accidents of this system is to be judged.

• Wind and Structures
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• v.28 no.6
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• pp.369-380
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• 2019

Statistical distributions are very useful in describing wind speed characteristics and in predicting wind power potential of a specified region. Although the Weibull distribution is the most popular one in wind energy literature, it does not seem to be able to perfectly fit all the investigated wind speed data in nature. Thus, many studies are still being conducted to find flexible distribution for modelling wind speed data. In this study, we propose a new Odd-Burr Rayleigh distribution for wind speed characterization. The Odd-Burr Rayleigh distribution with two shape parameters is flexible enough to model different shapes of wind speed data and thus it can be an alternative wind speed distribution for the assessment of wind energy potential. Therefore, suitability of the Odd-Burr Rayleigh distribution is investigated on real wind speed data taken from different regions in the South Africa. Numerical results of the conducted analysis confirm that the new Odd-Burr Rayleigh distribution is suitable for modelling most of the considered real wind speed cases and it also can be used for predicting wind power.

• Ocean Systems Engineering
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• v.13 no.3
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• pp.225-245
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• 2023

In the present paper, a numerical and experimental analysis for a wave energy converter under extreme environmental conditions is carried out. After the definition of design waves, including a 100-year return period stochastic sea state and a deterministic rogue wave condition, a numerical analysis using potential theory and a RANS equations solver are compared with experiments carried out at the Seakeeping Basin at the Technical University of Berlin. Results are discussed with special emphasis on the limits of potential theory methods for the evaluation of extreme wave conditions and the use of the presented methodology for early design stages.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.4
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• pp.105-115
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• 2007

This study identifies technical barriers and trends on Radio Frequency Identification(RFID) applications for military force, and investigates technical requirements for the RFID implementation on military information systems, based on the preliminary research results from the introductory RFID applications on Ammunition Information System(AIS). We first obtain technical requirements using the Quality Function Deployment(QFD) methods, and identify the areas for research and developments. Furthermore, based on the survey results from military experts and users, we provide the potential application areas for military RFID implementation. Conversely, a technology and research roadmap for RFID in the military system is developed.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.213-223
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• 1992

Although landfill has been heavily relied upon as a final hazardous waste disposal method in Korea, the legal and technical problems associated with the landfill severely hinder proper disposal of hazardous wastes. The single largest legal problem is simply that, in spite of the recent amendments, the law regulating the hazardous waste landfill is yet in its primitive stage that even the lawful landfill sites cannot be regarded safe. The technical problems include improper selection of landfill sites, poor design and construction of landfill facilities, and lack of QA/AC and post-closure cares. These technical problems stem from inexperience and lack of resources. For the reduction of the potential danger from the improper landfills of hazardous wastes, it is an immediate need to further refine the law and to resolve the technical problems.