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Importance Assessment of Multiple Microgrids Network Based on Modified PageRank Algorithm
Yeonwoo LEE(Yeonwoo LEE) 한국인공지능학회 2023 인공지능연구 (KJAI) Vol.11 No.2
This paper presents a comprehensive scheme for assessing the importance of multiple microgrids (MGs) network that includes distributed energy resources (DERs), renewable energy systems (RESs), and energy storage system (ESS) facilities. Due to the uncertainty of severe weather, large-scale cascading failures are inevitable in energy networks. making the assessment of the structural vulnerability of the energy network an attractive research theme. This attention has led to the identification of the importance of measuring energy nodes. In multiple MG networks, the energy nodes are regarded as one MG. This paper presents a modified PageRank algorithm to assess the importance of MGs that include multiple DERs and ESS. With the importance rank order list of the multiple MG networks, the core MG (or node) of power production and consumption can be identified. Identifying such an MG is useful in preventing cascading failures by distributing the concentration on the core node, while increasing the effective link connection of the energy flow and energy trade. This scheme can be applied to identify the most profitable MG in the energy trade market so that the deployment operation of the MG connection can be decided to increase the effectiveness of energy usages. By identifying the important MG nodes in the network, it can help improve the resilience and robustness of the power grid system against large-scale cascading failures and other unexpected events. The proposed algorithm can point out which MG node is important in the MGs power grid network and thus, it could prevent the cascading failure by distributing the important MG node’s role to other MG nodes.
Time-Series Estimation based AI Algorithm for Energy Management in a Virtual Power Plant System
Yeonwoo LEE(Yeonwoo LEE) 한국인공지능학회 2024 인공지능연구 (KJAI) Vol.12 No.1
This paper introduces a novel approach to time-series estimation for energy load forecasting within Virtual Power Plant (VPP) systems, leveraging advanced artificial intelligence (AI) algorithms, namely Long Short-Term Memory (LSTM) and Seasonal Autoregressive Integrated Moving Average (SARIMA). Virtual power plants, which integrate diverse microgrids managed by Energy Management Systems (EMS), require precise forecasting techniques to balance energy supply and demand efficiently. The paper introduces a hybrid-method forecasting model combining a parametric-based statistical technique and an AI algorithm. The LSTM algorithm is particularly employed to discern pattern correlations over fixed intervals, crucial for predicting accurate future energy loads. SARIMA is applied to generate time-series forecasts, accounting for non-stationary and seasonal variations. The forecasting model incorporates a broad spectrum of distributed energy resources, including renewable energy sources and conventional power plants. Data spanning a decade, sourced from the Korea Power Exchange (KPX) Electrical Power Statistical Information System (EPSIS), were utilized to validate the model. The proposed hybrid LSTM-SARIMA model with parameter sets (1, 1, 1, 12) and (2, 1, 1, 12) demonstrated a high fidelity to the actual observed data. Thus, it is concluded that the optimized system notably surpasses traditional forecasting methods, indicating that this model offers a viable solution for EMS to enhance short-term load forecasting.
Development of a Suction Set for Rapid Emergency Nursing Care and Verification of its Effectiveness
Yeonwoo Lee,Mihyeon Kim,Sihyeon Park,Huiju Lee,Soyeon Jin,Hyewon Jeong,Sun-Hee1 Moon 한국간호과학회 2021 한국간호과학회 학술대회 Vol.2021 No.10
Aims: Suction is one of the nursing procedures applied to oxygenate patients and maintain airway patency in hospitals. To prepare for occasional emergencies in the ward, a strategy is needed to implement prompt suction care. This study aimed to develop a suction set to provide rapid suction care in emergencies and assess its efficiency. Methods: Five ward nurses were recruited to interview users regarding their requests for suction sets. A supply list for suction set development was selected based on the participants’ opinions. A tool was developed to measure satisfaction with the suction set, and content validity was verified by five experts. The content validity index of the developed tool, was .91. The developed tool consisted of 15 items in four areas: six items of convenience, two items of credibility, four items of suitability, and three items of specificity. Satisfaction with the suction set were measured for 76 nurses from Jun to July 2021. The suction preparation duration before and after using the suction set were measured for 31 nurses in the ward during June 2021. Results: The suction set consisted of a latex suction catheter 6 Fr., a polyvinyl chloride suction catheter 14 Fr., poly-gloves, a straight connector, a polyvinyl chloride line, and saline. The average suction set satisfaction score was 61.05 ± 11.81, and the satisfaction of participants who performed suction care over 10 times per month was significant low than others (F=5.78, p = .005). The average suction preparation durations in a general condition and while using the developed kit were 58.50 ± 22.92 and 13.82 ± 6.46 s, respectively. Thus, using the developed suction set significantly reduced the suction preparation duration (t = 11.35, p < .001). Conclusions: The effectiveness of the suction set was verified through satisfaction surveys and measurement of suction preparation time. In an emergency, shortening the suction preparation duration using a suction set is necessary for providing rapid and efficient nursing care.
Lee, YeonWoo,Kim, MinCheol,Kim, Cheeyong Korea Multimedia Society 2017 The journal of multimedia information system Vol.4 No.4
This study is intended to analyze colors felt in TV commercials among video contents, to provide basic resources of color plan that can be applied to production of contents and to help acceptors to change their mood and to lower depression levels. Many studies have revealed the obvious correlation between depression and suicide, so the World Health Organization(WHO) recommends the importance of media by recognizing public that depression is a serious risk factor that leads to suicides and by asserting the necessity of establishing social environment for active treatment. Contents production companies have social and cultural responsibility to convey correct information and to make acceptors have positive emotions. If the result of colors that emotionally healthy people feel through this study is used for production of video contents, it will be helpful to lower the depression scale and to prevent and treat depression by providing visual comfort. In addition, it is expected to be used as an important basic resource for not only production of video contents but also color plan of industrial fields.
Lee, Yeonwoo The Institute of Internet 2016 International Journal of Internet, Broadcasting an Vol.8 No.4
This paper considers WiMedia UWB network based wireless ship area network (WSAN) so as to support high-quality multimedia video data services and important shipboard control data. In this paper, prioritized contention access (PCA) and distributed reservation protocol (DRP) based on WiMedia UWB (ECMA-368) MAC protocols are combined and proposed to support mixed high-quality video traffic and shipboard control data traffic applying varying DRP and PCA data periods according to channel condition and link parameter ptimization. It is shown that the proposed dynmaic channel allocation of WiMedia UWB MAC protocol can provide reliable mixed video and shipboard control data traffic as well.
Yeonwoo Lee 한국인터넷방송통신학회 2016 International Journal of Internet, Broadcasting an Vol.8 No.4
This paper considers WiMedia UWB network based wireless ship area network (WSAN) so as to support high-quality multimedia video data services and important shipboard control data. In this paper, prioritized contention access (PCA) and distributed reservation protocol (DRP) based on WiMedia UWB (ECMA- 368) MAC protocols are combined and proposed to support mixed high-quality video traffic and shipboard control data traffic applying varying DRP and PCA data periods according to channel condition and link parameter ptimization. It is shown that the proposed dynmaic channel allocation of WiMedia UWB MAC protocol can provide reliable mixed video and shipboard control data traffic as well.