• Journal of Power Electronics
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• v.18 no.4
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• pp.1245-1254
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• 2018

The stability of a grid-connected system (GCS) has become a critical issue with the increasing utilization of renewable energy sources. Under grid faults, however, a grid-connected inverter cannot work efficiently by using only the traditional droop control. In addition, the unbalance factor of voltage/current at the common coupling point (PCC) may increase significantly. To ensure the stable operation of a GCS under grid faults, the capability to compensate for grid imbalance should be integrated. To solve the aforementioned problem, an improved voltage-type grid-connected control strategy is proposed in this study. A negative sequence conductance compensation loop based on a positive sequence power droop control is added to maintain PCC voltage balance and reduce grid current imbalance, thereby meeting PCC power quality requirements. Moreover, a stable analysis is presented based on the small signal model. Simulation and experimental results verify the aforementioned expectations, and consequently, the effectiveness of the proposed control scheme.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.05a
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• pp.65-69
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• 2004

The need for developing sustainable solutions for managing the animal waste is vital for the future of the animal industry in North Carolina. As part of that process, the North Carolina Attorney General has concluded that the public interest will be served by the development and implementation of environmentally superior swine waste management technologies appropriate to each category of hog farms. To facilitate in the development, testing, and evaluation of potential technologies it is necessary that all aspects of environmental issues (air, water, soil, odor and odorants, and disease-transmitting vectors and airborne pathogens) be addressed as Part of a comprehensive strategy, Program OPEN (Odor, Pathogens, and Emissions of Nitrogen) Is comprehensively addressing these issues.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.393-398
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• 2007

Balance shaft has a key role in reducing a engine vibration in a vehicle and widely applied for current models. Since balance shaft module consists many sub-component and each part had its own operational characteristics, some different analysis background should be integrated into one sub-part in balance shaft module and this is the main obstacles in making a design process. Moreover, the balancing shaft rotating in high speed and such condition requires large safety factors in a design process owing to a lot of unexpected problems with the overwhelming rotation. Balance shaft is the core-component generating the intended unbalance as well as canceling the unbalance force or moment by the engine module. So, the balance shaft should meet the high fatigue resistance not to mention of NVH performance. In this paper, a design strategy focused on balance shaft is developed to build a optimal model considering a engine vibration. Putting the unbalance mass distribution as main design parameter, some candidate model is verified with structural and fatigue analysis most appropriate model is proposed here.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.2
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• pp.145-157
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• 2015

Objective : This study aimed to analyze a comprehensive feature of experimental research on Insamyangyoungtang and develop a strategy that can be used for experimental studies on Insamyangyoung-tang in the future. Method : The journal search was performed using six databases : PubMed, Chinese database (China Network Knowledge Infrastructure, [CNKI]), Japan database (Japan Science and Technology Information Aggregator, Electronic, [J-STAGE]) and three Korean databases (Oriental Medicine Advanced Searching Integrated System [OASIS], Research Information Service System [RISS], and Korean Studies Information Service System [KISS]). We used limited keywords and analyzed studies by publication year, experimental models, and the subjects of biological activities. The mechanism of pharmacological activity in accordance with the therapeutic effects of Insamyangyoung-tang was noted. Results and Conclusion : A total of 43 studies (6 domestic studies and 37 foreign ones) were examined according to the inclusion criteria of the experimental study. Research on the pharmacological activities of Insamyangyoung-tang showed its therapeutic effects on the nervous and immune systems, as well as its anti-aging, anti-fatigue, and hematopoietic effects. Additional efficacy and safety assessments and experimental and clinical studies should be performed to evaluate the mechanism of Insamyangyoung-tang. The present review has provided preliminary information for further studies on Insamyangyoung-tang.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.72-81
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• 2001

This study is aimed to review the previous research accomplishments with analysis of problems and to suggest the counter plan for the watershed management and the ongoing research strategy. Phytoremediation provides a cost-effective techniques having a merit of low investment and maintenance cost. It could be one of the best techniques, which is an alternative plan to overcome economical situation and lack of experts in our country. In forest watershed affected by waste water and heavy metal pollutants should be controlled by vegetative remediation system, but the disposal techniques of harvested plant materials should be developed. Also, high degree areas of natural vegetation as a key model to recover the vegetation should be well conserved. It is important to restore forest continuity between upper stream and lower stream basin with the restoration of damaged in forest watershed. It is established to integrated protection system for land use and management plan and to natural environment evaluation methods affected by projects such as erosion control and developments in stream and forest. In addition, I suggest the continuous environmental monitoring system to treat the pollutions concerned.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.43-48
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• 2017

In a previous study, we analyzed the transcriptome of Scolopendra subspinipes mutilans using next-generation sequencing technology and identified several antimicrobial peptide candidates. One of the peptides, scolopendrasin V, was selected based on the physicochemical properties of antimicrobial peptides using a bioinformatics strategy. In this study, we assessed the antimicrobial activities of scolopendrasin V using the radial diffusion assay and colony count assay. We also investigated the mode of action of scolopendrasin V using flow cytometry. We found that scolopendrasin V's mechanism of action involved binding to the surface of microorganisms via a specific interaction with lipopolysaccharides, lipoteichoic acid, and peptidoglycans, which are components of the bacterial membrane. These results provide a basis for developing peptide antibiotics.

• Environmental Engineering Research
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• v.22 no.4
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• pp.432-438
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• 2017

Slum settlement, a direct result of the rapid worldwide urbanization is a common site in most developing countries. Uganda is among the top African countries with high number of slums. The status of Katanga slum located in the low-lands between Mulago national hospital and Makerere University is a typical of many other slums within Uganda. This project proposal seeks to tackle urbanization challenges by specializing in slum upgrading as a sustainable way of curbing the menace. An integrated toilet, biogas, poultry and backyard gardening project is proposed as a channel of boosting the Katanga slum dwellers' economic, sanitation and domestic energy status. Designed to serve up to 30 households, the project will utilize residual wastes from poultry houses and toilets to produce biogas and slurry. The biogas yield will provide clean cooking fuel and energy for lighting, while the slurry used as organic fertilizers to improve vegetable yields. The social, economic and environmental impacts of the project will empower the vulnerable women and children within the slums and reduce water pollution and land degradation. This affordable project can be applied in developing countries experiencing slum settlement challenges as a strategy for reducing urbanization pressure.

• The Journal of Industrial Distribution & Business
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• v.10 no.9
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• pp.7-17
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• 2019

Purpose - In recent years, the bilateral political relationship between Vietnam and India was upgraded to strategic and comprehensive partnership. Thus, the purpose of this paper is to analyze current relations and prospects of the Vietnam-India trade. Research design, data and methodology - The data was mainly based on World Integrated Trade Solution (WITS) and Foreign Investment Agency of Vietnam Ministry of Planning and Investment (FIA) from 2010-2018. The relationship of the two countries has showed growth in all sectors, including trade cooperation. This paper focused on assessing the current relations of trade cooperation of the two countries and then andlyzed the prospects of trade cooperation in the next period. Result - The Indian Government's strategy shifted from "Look East" policy to "Look East" action by the end of 2015. Vietnam is a partner and a pillar of India's Look East policy (Muni, 2011). The governments of both countries should further strengthen exchanges and trade connections in order to provide cooperation opportunities for investors and businesses of the two countries. Conclusion - The paper discusses and gives an overview of the current status of the trade relations of Vietnam and India as well as lucidating the opportunities and challenges for two countries in the future.

• Structural Engineering and Mechanics
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• v.35 no.1
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• pp.19-35
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• 2010

This paper proposes a hybrid heuristic and criteria-based method of optimum design which combines the advantages of both the iterated simulated annealing (SA) algorithm and the rigorously derived optimality criteria (OC) for structural optimum design of reinforced concrete (RC) buildings under multi-load cases based on the current Chinese design codes. The entire optimum design procedure is divided into two parts: strength optimum design and stiffness optimum design. A modified SA with the strategy of adaptive feasible region is proposed to perform the discrete optimization of RC frame structures under the strength constraints. The optimum stiffness design is conducted using OC method with the optimum results of strength optimum design as the lower bounds of member size. The proposed method is integrated into the commercial software packages for building structural design, SATWE, and for finite element analysis, ANSYS, for practical applications. Finally, two practical frame-shear-wall structures (15-story and 30-story) are optimized to illustrate the effectiveness and practicality of the proposed optimum design method.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1244-1252
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• 2013

Sugar beet pulp is an abundant industrial waste material that holds a great potential for bioethanol production owing to its high content of cellulose, hemicelluloses, and pectin. Its structural and chemical robustness limits the yield of fermentable sugars obtained by hydrolyzation and represents the main bottleneck for bioethanol production. Physical (ultrasound and thermal) pretreatment methods were tested and combined with enzymatic hydrolysis by cellulase and pectinase to evaluate the most efficient strategy. The optimized hydrolysis process was combined with a fermentation step using a Saccharomyces cerevisiae strain for ethanol production in a single-tank bioreactor. Optimal sugar beet pulp conversion was achieved at a concentration of 60 g/l (39% of dry weight) and a bioreactor stirrer speed of 960 rpm. The maximum ethanol yield was 0.1 g ethanol/g of dry weight (0.25 g ethanol/g total sugar content), the efficiency of ethanol production was 49%, and the productivity of the bioprocess was 0.29 $g/l{\cdot}h$, respectively.