• Journal of Information Technology Services
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• v.15 no.4
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• pp.63-72
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• 2016

Critical infrastructure has been operating in a closed environment with a completely separate information system and in the private area. However, with the current ICT environment changes due to convergence and open platforms it has increased the threats and risks to critical infrastructure. The importance of cyber security is increasing in the infrastructure control system, such as the outbreak of Ukraine blackout in 2015 by a malicious code called 'black energy'. This thesis aims to recognize the importance and necessity of protecting the critical infrastructure service, designing a security framework reflecting environmental and characteristic changes, and analyzing the management system suitable for a security framework. We also propose a theoretical basis for constructing a new security framework by comparing and analyzing seven international security management system standards, such as NIST 800-82 and IEC 62443-2-1, which are used in the control system. As a result, the environment surrounding critical infrastructure changes with the characteristics of connectivity, openness, and finality was studied, and as a response to this, many scholars and institutions present critical infrastructure security frameworks as cycle enhancement type structures, risk management structures, and management domain expansion structures. In response, the security framework encompassing these structures, CISF (Critical Infrastructure Security Framework), was designed. Additionally, through the security related international standard and criterion analysis, as a newly designed security standard suitable for CISF, IEC 62443-2-1 is reviewed and suggestions are made.

• Journal of the Korea Convergence Society
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• v.8 no.1
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• pp.19-23
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• 2017

Energy is a vital resource for the economic growth and the social development for any country. As the industry becomes more sophisticated and the economy more grows, the electricity demand is increasing. So forecasting electricity demand is an important for electricity suppliers. Forecasting electricity demand makes it possible to distribute electricity demand. As the market for Negawatt market began to grow in Korea from 2014, the prediction of electricity consumption demand becomes more important. Moreover, power consumption forecasting provides a way for demand management to be directly or indirectly participated by consumers in the electricity market. We use Genetic Algorithms to predict the energy demand of the fishing industry in Jeju Island by using GDP, per capita gross national income, value add, and domestic electricity consumption from 1999 to 2011. Genetic Algorithm is useful for finding optimal solutions in various fields. In this paper, genetic algorithm finds optimal parameters. The objective is to find the optimal value of the coefficients used to predict the electricity demand and to minimize the error rate between the predicted value and the actual power consumption values.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.404-410
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• 2016

BACKGROUND/OBJECTIVE: Malnutrition and inflammation are reported as the most powerful predictors of mortality and morbidity in hemodialysis (HD) patients. Diet has a key role in modulating inflammation and dietary inflammatory index (DII) is a new tool for assessment of inflammatory potential of diet. The aim of this study was to evaluate the application of DII on dietary intake of HD patients and examine the associations between DII and malnutrition-inflammation markers. SUBJECTS/METHODS: A total of 105 subjects were recruited for this cross-sectional study. Anthropometric measurements, 3-day dietary recall, and pre-dialysis biochemical parameters were recorded for each subject. Subjective global assessment (SGA), which was previously validated for HD patients, and malnutrition inflammation score (MIS) were used for the diagnosis of protein energy wasting. DII was calculated according to average of 3-day dietary recall data. RESULTS: DII showed significant correlation with reliable malnutrition and inflammation indicators including SGA (r = 0.28, P < 0.01), MIS (r = 0.28, P < 0.01), and serum C-reactive protein (CRP) (r = 0.35, P < 0.001) in HD patients. When the study population was divided into three subgroups according to their DII score, significant increasing trends across the tertiles of DII were observed for SGA score (P = 0.035), serum CRP (P = 0.001), dietary energy (P < 0.001), total fat (P < 0.001), saturated fatty acids (P < 0.001), polyunsaturated fatty acids (P = 0.006), and omega-6 fatty acids (P = 0.01) intakes. CONCLUSION: This study shows that DII is a good tool for assessing the overall inflammatory potential of diet in HD patients.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.354-359
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• 2012

With the long-term use of fossil fuel, the whole world is suffering from serious abnormal changes in weather caused by global warming. For this reason, many countries are reducing greenhouse gas emissions out of obligation and the allowable emissions are assigned to each country. Korea is also putting much effort into reducing greenhouse gas emissions by 30 percent against BAU(Business As Usual) by 2020, and is pushing ahead with several projects such as 'Million Green Home' and 'Hatsal Gaduk Home' to expand the use of new renewable energy in house as part of its policy. This study was designed to come up with improvements and help to expand photovoltaic facilities, by investigating and analyzing the current state of photovoltaic facilities in the country and problems in installing them through an in-site reconnaissance and a survey in Jecheon area. As the result, it was found that residents in the area were inadequate to operate and install photovoltaic facilities, lacked awareness of them and felt burdened economically by managing and installing them, although they had a high awareness of solar energy and photovoltaic facilities are constantly increasing with governmental support. In conclusion, it is considered that as improvements, operational effects should be increased through development of techniques, factors to reduce the effects in operating them due to insufficient management and installation should be removed and awareness of residents need to be improved through long-term plans, political support and education of the government.

• Steel and Composite Structures
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• v.19 no.5
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• pp.1167-1184
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• 2015

Despite considerable life casualty and financial loss resulting from past earthquakes, many existing steel buildings are still seismically vulnerable as they have no lateral resistance or at least need some sort of retrofitting. Passive control methods with decreasing seismic demand and increasing ductility reduce rate of vulnerability of structures against earthquakes. One of the most effective and practical passive control methods is to use a shear panel system working as a ductile fuse in the structure. The shear Panel System, SPS, is located vertically between apex of two chevron braces and the flange of the floor beam. Seismic energy is highly dissipated through shear yielding of shear panel web while other elements of the structure remain almost elastic. In this paper, lateral behavior and related benefits of this system with narrow-flange link beams is experimentally investigated in chevron braced simple steel frames. For this purpose, five specimens with IPE (narrow-flange I section) shear panels were examined. All of the specimens showed high ductility and dissipated almost all input energy imposed to the structure. For example, maximum SPS shear distortion of 0.128-0.156 rad, overall ductility of 5.3-7.2, response modification factor of 7.1-11.2, and finally maximum equivalent viscous damping ratio of 35.5-40.2% in the last loading cycle corresponding to an average damping ratio of 26.7-30.6% were obtained. It was also shown that the beam, columns and braces remained elastic as expected. Considering this fact, by just changing the probably damaged shear panel pieces after earthquake, the structure can still be continuously used as another benefit of this proposed retrofitting system without the need to change the floor beam.

• STI Policy Review
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• v.4 no.1
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• pp.94-118
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• 2013

Innovation plays a large role in green growth. While it is a widely accepted view that, without innovation, it would be very difficult and costly to address major environmental issues, innovation itself tends to be constrained by limited access to eco-financing and is inherently risky, often requiring a long-term horizon. Although global consensus is more or less established as to the urgency and necessity of accelerating green innovation, the quality and quantity of financing in this area is largely insufficient, with increasing funding gaps in many countries. A new financial mechanism is urgently needed in order to re-orient financial flow and enable innovators to overcome the valleys of death that occur throughout the innovation cycle. A number of different modalities exist in financing the commercialisation of eco-innovation. Existing mechanisms have not been as successful as expected, revealing critical limits to furthering certain types of projects that are essential for economic and environmental progress. Experts' estimations have shown that the funding gap will widen in the coming years as demand for clean energy and green infrastructure rises, and as green technologies and innovation develop faster than the market for it can develop. Against this backdrop, the main purpose of this research is threefold: to identify issues and problems regarding current means of funding for eco-innovation and green projects; to provide insight into securing longterm green financing by looking at European cases; and ultimately to suggest policy implications for designing and implementing eco-specific financial instruments, focusing on governments' roles in sustainable financing for eco-innovation. This study analyses different models of financing mechanisms, a mix of public and private funds, in view of suggesting conditions for the sustainable financing of green projects, especially for large-scale high-risk projects. Based on the findings from the analyses of mechanisms and the shortcomings of the existing funding modalities, this study ultimately suggests policy implications for effectively supporting the commercialisation of eco-innovation.

• Journal of Information Processing Systems
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• v.15 no.3
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• pp.593-603
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• 2019

In wearable healthcare systems, sensor devices can be deployed in places around the human body such as the stomach, back, arms, and legs. The sensors use tiny batteries, which have limited resources, and old sensor batteries must be replaced with new batteries. It is difficult to deploy sensor devices directly into the human body. Therefore, instead of replacing sensor batteries, increasing the lifetime of sensor devices is more efficient. A transmission power control (TPC) algorithm is a representative technique to increase the lifetime of sensor devices. Sensor devices using a TPC algorithm control their transmission power level (TPL) to reduce battery energy consumption. The TPC algorithm operates on a closed-loop mechanism that consists of two parts, such as sensor and sink devices. Most previous research considered only the sink part of devices in the closed-loop. If we consider both the sensor and sink parts of a closed-loop mechanism, sensor devices reduce energy consumption more than previous systems that only consider the sensor part. In this paper, we propose a new approach to consider both the sensor and sink as part of a closed-loop mechanism for efficient energy management of sensor devices. Our proposed approach judges the current channel condition based on the values of various body sensors. If the current channel is not optimal, sensor devices maintain their current TPL without communication to save the sensor's batteries. Otherwise, they find an optimal TPL. To compare performance with other TPC algorithms, we implemented a TPC algorithm and embedded it into sensor devices. Our experimental results show that our new algorithm is better than other TPC algorithms, such as linear, binary, hybrid, and ATPC.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.625-633
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• 2011

A long-term water quality monitoring in the Han River Basin reveals a consistent increasing trend for the concentration of refractory organic matter (R-OM) in major monitoring sites of the watershed. Because the determination of R-OM concentrations typically requires a long time of microbial incubation, it is essential to present the estimation indices for R-OM for an efficient watershed management. In this study, a number of surface water samples were classified into three groups, each of which were collected from Lake Paldang, rivers at rain and non-rain events, respectively. The corresponding R-OM concentrations were correlated with biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC) concentrations as well as ultraviolet and fluorescence intensities of the filtered samples. Among the traditional organic matter parameters, TOC exhibited the highest correlation coefficient with the R-OM concentrations regardless of the types of the sample groups. The equations for conversing TOC into R-OM concentrations were finally suggested as $0.43{\times}TOC+1.12$, $0.44{\times}TOC+0.61$, $0.24{\times}TOC+1.28$ for river samples at rain and non-rain events, and lake samples, respectively. TOC-BOD(C), the values of the TOC concentrations subtracted by carbon-converted BOD concentrations, was a good index for estimating the absolute concentrations of R-OM. UV absorbance at 254 nm was well correlated with R-OM concentrations of river samples while fluorescence intensities at 350 nm showed an excellent relationship with R-OM concentration of the lake samples. Our results suggests that simple spectroscopic parameters could be applied for in-situ monitoring tool techniques in watersheds.

• New & Renewable Energy
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• v.18 no.4
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• pp.70-78
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• 2022

To respond to global warming, there is an increasing interest in eco-friendly alternative energy sources. Therefore, unused forest biomass that has been neglected due to a lack of marketability is attracting attention. With the introduction of the "unused forest biomass certification system" in 2019, ways of determining quantity of unused forest biomass have steadily increased. However, there have been reported cases whereby unused forest biomass weighed more than the amount of harvested trees. It was found that it was possible that forest resources that can be used as round wood were mixed with unused forest biomass. In this context, this study aimed to estimate the amount of mixed round wood in the unused forest biomass supply. The relative expression of growing stock/ha versus the amount of final clearing/ha collected was modeled (y=1.490x-94.341, R²=0.861). As a result, it was found that round wood was mixed into the unused forest biomass, contributing to the disparity observed between the weighted forest biomass and the amount of trees harvested. In conclusion, proper declaration and certification procedures should be carried out for the use of forest resources and promoting unused forest biomass usage.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.7
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• pp.1873-1893
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• 2023

The development of lightweight, low energy and small-sized sensors incorporated with the wireless networks has brought about a phenomenal growth of Wireless Sensor Networks (WSNs) in its different fields of applications. Moreover, the routing of data is crucial in a wide number of critical applications that includes ecosystem monitoring, military and disaster management. However, the time-delay, energy imbalance and minimized network lifetime are considered as the key problems faced during the process of data transmission. Furthermore, only when the functionality of cluster head selection is available in WSNs, it is possible to improve energy and network lifetime. Besides that, the task of cluster head selection is regarded as an NP-hard optimization problem that can be effectively modelled using hybrid metaheuristic approaches. Due to this reason, an Improved Coyote Optimization Algorithm-based Clustering Technique (ICOACT) is proposed for extending the lifetime for making efficient choices for cluster heads while maintaining a consistent balance between exploitation and exploration. The issue of premature convergence and its tendency of being trapped into the local optima in the Improved Coyote Optimization Algorithm (ICOA) through the selection of center solution is used for replacing the best solution in the search space during the clustering functionality. The simulation results of the proposed ICOACT confirmed its efficiency by increasing the number of alive nodes, the total number of clusters formed with the least amount of end-to-end delay and mean packet loss rate.