• Title/Summary/Keyword: system uncertainty

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Optimal Hierarchical Design Methodology for AESA Radar Operating Modes of a Fighter (전투기 AESA 레이더 운용모드의 최적 계층구조 설계 방법론)

  • Heungseob Kim;Sungho Kim;Wooseok Jang;Hyeonju Seol
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.46 no.4
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    • pp.281-293
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    • 2023
  • This study addresses the optimal design methodology for switching between active electronically scanned array (AESA) radar operating modes to easily select the necessary information to reduce pilots' cognitive load and physical workload in situations where diverse and complex information is continuously provided. This study presents a procedure for defining a hidden Markov chain model (HMM) for modeling operating mode changes based on time series data on the operating modes of the AESA radar used by pilots while performing mission scenarios with inherent uncertainty. Furthermore, based on a transition probability matrix (TPM) of the HMM, this study presents a mathematical programming model for proposing the optimal structural design of AESA radar operating modes considering the manipulation method of a hands on throttle-and-stick (HOTAS). Fighter pilots select and activate the menu key for an AESA radar operation mode by manipulating the HOTAS's rotary and toggle controllers. Therefore, this study presents an optimization problem to propose the optimal structural design of the menu keys so that the pilot can easily change the menu keys to suit the operational environment.

Anxiety in hospitalized patients with infectious diseases placed in isolation: a concept analysis (감염병 격리 입원환자의 불안: 개념분석)

  • Chan-Mi Moon;Ye Seul Im
    • Journal of Korean Biological Nursing Science
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    • v.25 no.4
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    • pp.243-253
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    • 2023
  • Purpose: This study conducted a concept analysis to clarify the meaning of anxiety in hospitalized patients with infectious diseases who have been placed in isolation. Methods: This study used Walker and Avant's process of concept analysis. Results: Anxiety in hospitalized patients with infectious diseases who have been placed in isolation can be defined by the following attributes: 1) fear, 2) guilt, 3) isolation, 4) discrimination, 5) frustration, 6) shame, and 7) uncertainty. The antecedents of anxiety were as follows: 1) a lack of information about infectious diseases, 2) restrictions of movement, 3) blockage of the social support system, 4) helplessness, and 5) negative biases. The consequences of anxiety were 1) internalized stigma, 2) loss of confidence, 3) lack of social activities and avoidance, 4) insomnia, 5) poor quality of life. Conclusion: The definition and attributes of anxiety identified in this study can be applied to enhance the understanding of anxiety in hospitalized patients with infectious diseases who have been placed in isolation. Systematic suppose should also be provided to reduce anxiety in these patients.

Study on Emerging Security Threats and National Response

  • Il Soo Bae;Hee Tae Jeong
    • International Journal of Advanced Culture Technology
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    • v.11 no.4
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    • pp.34-41
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    • 2023
  • The purpose of this paper is to consider the expansion of non-traditional security threats and the national-level response to the emergence of emerging security threats in ultra-uncertain VUCA situations. As a major research method for better analysis, the theoretical approach was referred to papers published in books and academic journals, and technical and current affairs data were studied through the Internet and literature research. The instability and uncertainty of the international order and security environment in the 21st century brought about a change in the security paradigm. Human security emerged as the protection target of security was expanded to individual humans, and emerging security was emerging as the security area expanded. Emerging security threatsthat have different characteristicsfrom traditionalsecurity threats are expressed in various ways, such as cyber threats, new infectious disease threats, terrorist threats, and abnormal climate threats. First, the policy and strategic response to respond to emerging security threats is integrated national crisis management based on artificial intelligence applying the concept of Foresight. Second, it is to establish network-based national crisis management smart governance. Third, it is to maintain the agile resilience of the concept of Agilience. Fourth, an integrated response system that integrates national power elements and national defense elements should be established.

Development and evaluation of a model-based HSE risk assessment module for HSE management in offshore wind power (해상풍력발전의 HSE 관리를 위한 모델기반 HSE 위험성 평가 모듈 개발 및 평가)

  • Seong Rae Kim;Keon Woo Nam;Tae Kyong Lee;Dae Young Kang;Joon Young Kim
    • Journal of the Korean Society of Systems Engineering
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    • v.19 no.2
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    • pp.74-91
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    • 2023
  • This study provides an in-depth comparison and analysis of various risk assessment models widely used in modern industries, and proposes the most suitable model for risk assessment of offshore wind power in Korea. The assessment models were selected by considering various factors such as the purpose of risk assessment, stakeholder requirements, and characteristics of offshore wind power. We also emphasized the importance of using different risk assessment models in combination in situations of high uncertainty. To systematize the combination of risk assessment models, we used systems engineering which is effective to develop a new system. Systems engineering was used to define the complete, traceable functions from site requirements, and model-based systems engineering was used to manage the design information from requirements to detailed functions in a single model. The developed risk assessment module provide automatic conversion between risk assessment models to enable risk assessment suitable for offshore wind power. The functionality and usability of the offshore wind risk assessment module were verified by the evaluation of three wind power experts.

A long-term tunnel settlement prediction model based on BO-GPBE with SHM data

  • Yang Ding;Yu-Jun Wei;Pei-Sen Xi;Peng-Peng Ang;Zhen Han
    • Smart Structures and Systems
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    • v.33 no.1
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    • pp.17-26
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    • 2024
  • The new metro crossing the existing metro will cause the settlement or floating of the existing structures, which will have safety problems for the operation of the existing metro and the construction of the new metro. Therefore, it is necessary to monitor and predict the settlement of the existing metro caused by the construction of the new metro in real time. Considering the complexity and uncertainty of metro settlement, a Gaussian Prior Bayesian Emulator (GPBE) probability prediction model based on Bayesian optimization (BO) is proposed, that is, BO-GPBE. Firstly, the settlement monitoring data are analyzed to get the influence of the new metro on the settlement of the existing metro. Then, five different acquisition functions, that is, expected improvement (EI), expected improvement per second (EIPS), expected improvement per second plus (EIPSP), lower confidence bound (LCB), probability of improvement (PI) are selected to construct BO model, and then BO-GPBE model is established. Finally, three years settlement monitoring data were collected by structural health monitoring (SHM) system installed on Nanjing Metro Line 10 are employed to demonstrate the effectiveness of BO-GPBE for forecasting the settlement.

Evaluations of a Commercial CLEANBOLUS-WHITE for Clinical Application

  • Geum Bong Yu;Jung-in Kim;Jaeman Son
    • Progress in Medical Physics
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    • v.35 no.1
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    • pp.10-15
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    • 2024
  • Purpose: This study aimed to comprehensively investigate the diverse characteristics of a novel commercial bolus, CLEANBOLUS-WHITE (CBW), to ascertain its suitability for clinical application. Methods: The evaluation of CBW encompassed both physical and biological assessments. Physical parameters such as mass density and shore hardness were measured alongside analyses of element composition. Biological evaluations included assessments for skin irritation and cytotoxicity. Dosimetric properties were examined by calculating surface dose and beam quality using a treatment planning system (TPS). Additionally, doses were measured at maximum and reference depths, and the results were compared with those obtained using a solid water phantom. The effect of air gap on dose measurement was also investigated by comparing measured doses on the RANDO phantom, under the bolus, with doses calculated from the TPS. Results: Biological evaluation confirmed that CBW is non-cytotoxic, nonirritant, and non-sensitizing. The bolus exhibited a mass density of 1.02 g/cm3 and 14 shore 00. Dosimetric evaluations revealed that using the 0.5 cm CBW resulted in less than a 1% difference compared to using the solid water phantom. Furthermore, beam quality calculations in the TPS indicated increased surface dose with the bolus. The air gap effect on dose measurement was deemed negligible, with a difference of approximately 1% between calculated and measured doses, aligning with measurement uncertainty. Conclusions: CBW demonstrates outstanding properties for clinical utilization. The dosimetric evaluation underscores a strong agreement between calculated and measured doses, validating its reliability in both planning and clinical settings.

Smart composite repetitive-control design for nonlinear perturbation

  • ZY Chen;Ruei-Yuan Wang;Yahui Meng;Timothy Chen
    • Steel and Composite Structures
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    • v.51 no.5
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    • pp.473-485
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    • 2024
  • This paper proposes a composite form of fuzzy adaptive control plan based on a robust observer. The fuzzy 2D control gains are regulated by the parameters in the LMIs. Then, control and learning performance indices with weight matrices are constructed as the cost functions, which allows the regulation of the trade-off between the two performance by setting appropriate weight matrices. The design of 2D control gains is equivalent to the LMIs-constrained multi-objective optimization problem under dual performance indices. By using this proposed smart tracking design via fuzzy nonlinear criterion, the data link can be further extended. To evaluate the performance of the controller, the proposed controller was compared with other control technologies. This ensures the execution of the control program used to track position and trajectory in the presence of great model uncertainty and external disturbances. The performance of monitoring and control is verified by quantitative analysis. The goals of this paper are towards access to adequate, safe and affordable housing and basic services, promotion of inclusive and sustainable urbanization and participation, implementation of sustainable and disaster-resilient buildings, sustainable human settlement planning and manage. Therefore, the goal is believed to achieved in the near future by the ongoing development of AI and control theory.

System Construction and Data Development of National Standard Reference for Renewable Energy - Model-Based Standard Meteorological Year (신재생에너지 국가참조표준 시스템 구축 및 개발 - 모델 기반 표준기상년)

  • Boyoung Kim;Chang Ki Kim;Chang-yeol Yun;Hyun-goo Kim;Yong-heack Kang
    • New & Renewable Energy
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    • v.20 no.1
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    • pp.95-101
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    • 2024
  • Since 1990, the Renewable Big Data Research Lab at the Korea Institute of Energy Technology has been observing solar radiation at 16 sites across South Korea. Serving as the National Reference Standard Data Center for Renewable Energy since 2012, it produces essential data for the sector. By 2020, it standardized meteorological year data from 22 sites. Despite user demand for data from approximately 260 sites, equivalent to South Korea's municipalities, this need exceeds the capability of measurement-based data. In response, our team developed a method to derive solar radiation data from satellite images, covering South Korea in 400,000 grids of 500 m × 500 m each. Utilizing satellite-derived data and ERA5-Land reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF), we produced standard meteorological year data for 1,000 sites. Our research also focused on data measurement traceability and uncertainty estimation, ensuring the reliability of our model data and the traceability of existing measurement-based data.

Forest Biomass Utilization for Energy Based on Scientifically Grounded and Orthodox (산림바이오매스에너지에 관한 과학적 근거에 따른 통설적 접근)

  • Seung-Rok Lee;Gyu-Seong Han
    • New & Renewable Energy
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    • v.20 no.1
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    • pp.145-174
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    • 2024
  • Addressing climate change necessitates evidence-based policies grounded in science. The use of forest biomass for energy production is based on a broad scientific consensus at the international level. However, some environmental groups in South Korea are opposing this system of energy production. Through this study, the authors aim to reduce unnecessary confusion and foster an atmosphere conducive to meaningful evidence-based policies. We have classified the issue into eight categories: biological carbon cycle, carbon debt, nature-based solutions, air emissions, cascading principles and sustainability certification, forest environmental impacts, climate change litigation, and the behavior of environmental groups and public perception. Consequently, the following key points were derived: (1) the actions of some environmental groups seem to follow a similar pattern to denialist behavior that denies climate change and climate science; (2) the quality of evidence for campaigns that oppose the use of forest biomass for energy production is low, with a tendency to overgeneralize information, high uncertainty, and difficulty in finding new claims.; (3) most of the public believes that forest biomass energy is necessary, and the governments of major countries are aware of its importance. Significantly, Forest biomass for energy is based on an overwhelming level of scientific consensus recognized internationally.

Strategic Conflict Management for Safe Urban Air Mobility Operations (안전한 도심항공교통 운영을 위한 전략적 충돌 관리 방안)

  • Tae gyeong Yun;Soohwan Oh
    • Journal of Advanced Navigation Technology
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    • v.28 no.4
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    • pp.450-458
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    • 2024
  • Urban air mobility (UAM) shows great promise for commercialization, yet the technical foundations for ensuring safety in large-scale operations remain a challenge. The purpose of this paper was to analyze current air traffic conflict management techniques in order to develop strategies for implementing strategic conflict management within UAM traffic management systems. We found that UAM conflict management can benefit from demand and capacity balancing techniques, and a system-wide approach is essential. Specifically, the use of data sharing and probabilistic methods is essential for addressing flight time uncertainty and large-scale UAM operations effectively.