• Journal of the Korean Solar Energy Society
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• v.40 no.5
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• pp.13-22
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• 2020

Day ahead forecast is necessary for the electricity market to stabilize the electricity penetration. Numerical weather prediction is usually employed to produce the solar irradiance as well as electric power forecast for longer than 12 hours forecast horizon. Korea Meteorological Administration operates the UM-LDAPS model to produce the 36 hours forecast of hourly total irradiance 4 times a day. This study interpolates the hourly total irradiance into 15 minute instantaneous irradiance and then compare them with observed solar irradiance at four ground stations at 1 minute resolution. Numerical weather prediction model employed here was produced at 00 UTC or 18 UTC from January to December, 2018. To compare the statistical model for the forecast horizon less than 3 hours, smart persistent model is used as a reference model. Relative root mean square error of 15 minute instantaneous irradiance are averaged over all ground stations as being 18.4% and 19.6% initialized at 18 and 00 UTC, respectively. Numerical weather prediction is better than smart persistent model at 1 hour after simulation began.

• Smart Structures and Systems
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• v.30 no.2
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• pp.159-172
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• 2022

To improve the accuracy of the standard penetration test (SPT) results, smart measurement system, which considers the energy transfer ratio into the sampler (ETR_Sampler), is required. The objective of this study is to evaluate the effects of joints and rod length on the transferred energy into the sampler. The energy transfer ratios into the rod head (ETR_Head) and ETR_Sampler, and the energy ratio from the head to the sampler (ER_HS) were obtained using energy modules, which were installed at the rod head and above the SPT sampler. Linear regression analyses are conducted to correlate the ER_HS with the number of joints, rod length, and SPT N-values. In addition, the dynamic resistances are calculated using both transferred energies into the rod head and into the sampler, and are compared with the corrected cone tip resistance measured from the cone penetration test (CPT). While the ETR_Head are generally constant, but the ETR_Sampler and ER_HS gradually decrease along the depth or the number of joints, except at certain depths with high SPT N-values. Thus, the ER_HS can be estimated using the number of joints, rod length, and SPT N-values. The dynamic resistance evaluated by E_Sampler produces a better correlation with the corrected cone tip resistance than that by E_Head. This study suggests that transferred energy into the SPT sampler may be effectively used for more accurate subsurface characterization.

• Journal of IKEEE
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• v.27 no.4
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• pp.657-667
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• 2023

This paper proposes two-stage optimization framework to re-estimate the photovoltaic (PV) hosting capacity (HC) by improving parameters for voltage controls of the smart inverter. In the first stage, PV HC is estimated considering Volt-Var (VV) and Volt-Watt (VW) controls, aligning with IEEE Std 1547-2018 guidelines. In the second stage, adjust parameters of VV and VW to improve HC. To investigate the performance of the proposed algorithm, simulations conducted using OpenDSS on an IEEE 37-bus system. The results demonstrate that effectively increases PV HC.

• The Journal of Economics, Marketing and Management
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• v.8 no.3
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• pp.23-36
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• 2020

Purpose: The purpose of this study is to identify the strategic direction of organizations and their employees to efficiently utilize smart factories and enhance business performance among Korean manufacturing companies. Research design, data, and methodology: We derived a structured research model to check the mediated effect of utilization of smart factory between the characteristics of smart factory and the innovation activities. Results: Quality characteristics of smart factory and Innovation activities were all found to have a statistically significant effect on utilization of smart factory, utilization of smart factory was found to have a statistically significant effect on the business performance. And it has been shown that the utilization of smart factory is partially mediated relative to the quality characteristics of smart factory and business performance and relative to innovation activities and business performance. Conclusions: Smart factory builders can reflect the areas that affect utilization of the smart factory in their strategies by considering the quality characteristics of the smart factory and innovation Activities. Therefore, smart factory builders can identify the quality characteristics of smart factory and reflect them in the process and analyze active utilize measures through the innovative activities of the employees of the organization, thereby influencing business performance.

• International Journal of Computer Science & Network Security
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• v.24 no.4
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• pp.87-106
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• 2024

Vehicle-to-Home (V2H) and Home Centralized Photovoltaic (HCPV) systems can address various energy storage issues and enhance demand response programs. Renewable energy, such as solar energy and wind turbines, address the energy gap. However, no energy management system is currently available to regulate the uncertainty of renewable energy sources, electric vehicles, and appliance consumption within a smart microgrid. Therefore, this study investigated the impact of solar photovoltaic (PV) panels, electric vehicles, and Micro-Grid (MG) storage on maximum solar radiation hours. Several Deep Learning (DL) algorithms were applied to account for the uncertainty. Moreover, a Reinforcement Learning HCPV (RL-HCPV) algorithm was created for efficient real-time energy scheduling decisions. The proposed algorithm managed the energy demand between PV solar energy generation and vehicle energy storage. RL-HCPV was modeled according to several constraints to meet household electricity demands in sunny and cloudy weather. Simulations demonstrated how the proposed RL-HCPV system could efficiently handle the demand response and how V2H can help to smooth the appliance load profile and reduce power consumption costs with sustainable power generation. The results demonstrated the advantages of utilizing RL and V2H as potential storage technology for smart buildings.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.1-7
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• 2017

The collection and analysis of power information in the smart grid is essential. The collected utilize power information can be used to efficiently utilize power such as power generation and distribution. The role of smart meters communication through wire and wireless cable is important for collecting power information. Recently, many countries around the world are establishing international standards or unique standards of smart meter communication for power information collection of many smart meters. Thus, this paper investigates smart meter related papers and materials, and summarizes international and national standards for smart meter communication.

• International Journal of Computer Science & Network Security
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• v.21 no.7
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• pp.1-7
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• 2021

An amazing growth in the field of Internet of Things (IoT) and Blockchain based smart cities from both industry and academia has been witnessed in the recent years. There are many smart applications such as intelligent transportation, smart banking, improving the life style of citizen, energy consumption and managing the waste in the city, handling home needs are supporting the Smart city concept. These applications are profoundly supported by the advanced technologies like Blockchain as well as IoT in the recent past. Smart cities can be supported by the Blockchain core concepts such as secure, transparent, decentralized and immutable nature. Still, Blockchain and IoT technologies implementation in smart cities are in their early stages and significant research efforts are desirable to integrate them. This review article explores the roles and responsibilities of Blockchain and IoT in building smart cities.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.369-370
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• 2004

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.447-447
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• 1999

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.759-760
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• 2005