• 제목/요약/키워드: operational strategy

검색결과 454건 처리시간 0.021초

A High Efficiency LLC Resonant Converter-based Li-ion Battery Charger with Adaptive Turn Ratio Variable Scheme

  • Choi, Yeong-Jun;Han, Hyeong-Gu;Choi, See-Young;Kim, Sang-Il;Kim, Rae-Young
    • Journal of Electrical Engineering and Technology
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    • 제13권1호
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    • pp.124-132
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    • 2018
  • This paper proposes an LLC resonant converter based battery charger which utilizes an adaptive turn ratio scheme to achieve a wide output voltage range and high efficiency. The high frequency transformer of the LLC converter of the proposed strategy has an adaptively changed turn ratio through the auxiliary control circuit. As a result, an optimized converter design with high magnetizing inductance is possible, while minimizing conduction and turn-off losses and providing a regulated voltage gain to properly charge the lithium ion battery. For a step-by-step explanation, operational principle and optimal design considerations of the proposed converter are illustrated in detail. Finally, the effectiveness of the proposed strategy is verified through various experimental results and efficiency analysis based on prototype 300W Li-ion battery charger and battery pack.

Banding the World Together; The Global Growth of Control Banding and Qualitative Occupational Risk Management

  • Zalk, David M.;Heussen, Ga Henri
    • Safety and Health at Work
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    • 제2권4호
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    • pp.375-379
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    • 2011
  • Control Banding (CB) strategies to prevent work-related illness and injury for 2.5 billion workers without access to health and safety professionals has grown exponentially this last decade. CB originates from the pharmaceutical industry to control active pharmaceutical ingredients without a complete toxicological basis and therefore no occupational exposure limits. CB applications have broadened into chemicals in general - including new emerging risks like nanomaterials and recently into ergonomics and injury prevention. CB is an action-oriented qualitative risk assessment strategy offering solutions and control measures to users through "toolkits". Chemical CB toolkits are user-friendly approaches used to achieve workplace controls in the absence of firm toxicological and quantitative exposure information. The model (technical) validation of these toolkits is well described, however firm operational analyses (implementation aspects) are lacking. Consequentially, it is often not known if toolkit use leads to successful interventions at individual workplaces. This might lead to virtual safe workplaces without knowing if workers are truly protected. Upcoming international strategies from the World Health Organization Collaborating Centers request assistance in developing and evaluating action-oriented procedures for workplace risk assessment and control. It is expected that to fulfill this strategy's goals, CB approaches will continue its important growth in protecting workers.

A Brief Scrutiny of Malawi's Policy on Nuclear Power

  • Katengeza, Estiner Walusungu
    • Journal of Radiation Protection and Research
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    • 제45권4호
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    • pp.147-153
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    • 2020
  • Background: Malawi's 2018 National Energy Policy includes nuclear power as an energy option with an operational 100 MW targeted for 2035. Materials and Methods: This paper challenges the scope of the policy on nuclear power by reviewing its implementation strategy and comparing it to: the strategy established for coal in the same policy; some experiences from other countries; and documents by the International Atomic Energy Agency (IAEA) relating to establishing a national position on nuclear power and infrastructural requirements for a nuclear power program. Results and Discussion: It is found that the pro-nuclear position is uninformed, and targets are unrealistic owing to a lack of understanding of nature of nuclear power including the requirements for safety, security and safeguards, and nuclear infrastructure. It is apparent that neither consultation nor a proper analysis were comprehensively conducted for nuclear. Though the national energy policy suggests a national position for nuclear energy, the content does not demonstrate that the position was arrived at knowledgeably. Conclusion: Thus, nuclear power may presently be viewed as a potential energy option that is yet to be seriously considered. It is important to build an appropriate level of literacy on nuclear science and technology for policy makers, key stakeholders, and the public to be better positioned for strategizing on nuclear power.

Research on the Growth Strategy of University Technology Holding Companies Based on Public Technology

  • YUN, Jeong-Keun
    • 동아시아경상학회지
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    • 제8권4호
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    • pp.29-43
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    • 2020
  • Purpose - Although it has been 10 years since the university technology holding company was launched, it is currently facing operational limitations. The purpose of this study is to study the growth strategy of university technology holding companies by investigating the status and problems of university technology holding companies. Research design, data, and methodology - In this study, the status of university technology holding companies was analyzed based on the survey data issued by the University Technology Holding Companies Association. Due to the lack of research on university technology holding companies, policy alternatives were suggested by examining problems based on literature research. Result - In this study, an alternative to strengthening the competitiveness of technology holding companies and supporting policies was suggested. As a result of the research, it was discovered as a policy alternative to enhance the independence of technology-owned subsidiaries, develop outstanding talents, and expand the marketing of support programs to create results based on technology holding companies. Conclusion - In previous studies, alternatives to technology commercialization policies have been suggested, but studies on the role and status of detailed technology holding companies are insufficient, and the operation system of technology holding companies and discovery of future growth models are insufficient compared to overseas cases. Therefore, in this study, various policy innovation measures are presented as examples.

Ionic Passivation and Oxidation Dynamics for Enhanced Viability of Copper-Based On-Skin Bioelectrodes in Biological Environments

  • Jungho Lee;Gaeun Yun;Juhyeong Jeon;Phuong Thao Le;Seung Whan Kim;Geunbae Lim
    • 센서학회지
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    • 제32권6호
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    • pp.352-356
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    • 2023
  • The integration of bioelectronic devices with the skin is a promising strategy for personalized healthcare monitoring and diagnostics. On-skin bioelectrodes hold great potential for the real-time tracking of physiological parameters. However, persistent challenges of stability and reliability have instigated exploration beyond conventional noble metals. This study focuses on the ionic passivation and oxidation dynamics of copper-based on-skin thin-film bioelectrodes. Through parylene chemical vapor deposition, we harness a controlled thin film of parylene insulation to counter the intrinsic susceptibility of copper to oxidation in the ionic environment. The results represent the relationship among the parylene insulation thickness, copper oxidation, and electrode impedance over temporal intervals. Comparative analyses indicate that the short-term stability of the copper electrode is comparable to that of the gold electrode. Therefore, we propose a cost-effective strategy for fabricating copper-based on-skin bioelectrodes by introducing enhanced ionic stability within a discernible operational timeframe. This study enriches our understanding of on-skin bioelectronics and affordable material choices for practical use in wearable healthcare devices.

공연종사자 피난을 위한 안전시설의 운영전략 연구 (A Study of the Safety Facilities Operation Strategies for Performing Arts Workers Evacuation)

  • 정성학;박용규
    • 대한안전경영과학회지
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    • 제26권1호
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    • pp.63-74
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    • 2024
  • The objectives of this study is to classify evacuation types, derive the characteristics of 4 types, develop and discover evacuation routes within the performance hall space, and present the statistical classification results of the evacuation classification model by classification type. To achieve this purpose, the characteristics of each evacuation type's four types are applied through a network reliability analysis method and utilized for institutional improvement and policy. This study applies for the building law, evacuation and relief safety standards when establishing a performance hall safety management plan, and reflects it in safety-related laws, safety standards, and policy systems. Statistical data by evacuation type were analyzed, and measurement characteristics were compared and analyzed by evacuation types. Evaluate the morphological similarity and reliability of evacuation types according to door width and passage length and propose the install position of evacuation guidance sign boards. The results of this study are expected to be used as basic data to provide operation strategies for safety facility evacuation information sign boards according to evacuation route classification types when taking a safety management plan. The operation strategy for the evacuation sign boards installation that integrates employee guidance and safety training is applied to the performance hall safety management plan. It will contribute to establishing an operational strategy for performance space safety when constructing performance facilities in the future.

PBIS: A Pre-Batched Inspection Strategy for spent nuclear fuel inspection robot

  • Bongsub Song;Jongwon Park;Dongwon Yun
    • Nuclear Engineering and Technology
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    • 제55권12호
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    • pp.4695-4702
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    • 2023
  • Nuclear power plants play a pivotal role in the global energy infrastructure, fulfilling a substantial share of the world's energy requirements in a sustainable way. The management of these facilities, especially the handling of spent nuclear fuel (SNF), necessitates meticulous inspections to guarantee operational safety and efficiency. However, the prevailing inspection methodologies lean heavily on human operators, which presents challenges due to the potential hazards of the SNF environment. This study introduces the design of a novel Pre-Batched Inspection Strategy (PBIS) that integrates robotic automation and image processing techniques to bolster the inspection process. This methodology deploys robotics to undertake tasks that could be perilous or time-intensive for humans, while image processing techniques are used for precise identification of SNF targets and regulating the robotic system. The implementation of PBIS holds considerable promise in minimizing inspection time and enhancing worker safety. This paper elaborates on the structure, capabilities, and application of PBIS, underlining its potential implications for the future of nuclear energy inspections.

Qualitative Literature Analysis: The Meaningful Association between ESG Management and Economic Development

  • Anthony NJUGUNA;Phouthakannha NANTHARATH;Eungoo KANG
    • 산경연구논집
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    • 제15권5호
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    • pp.29-37
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    • 2024
  • Purpose: Numerous prior researchers have identified only that sustainable management of ESG factors promotes business value creation and shapes enhanced innovation performance. This study aims to determine the positive relationships between ESG management and economic development, focusing on the mutual benefits and risks and the various stakeholders involved in managing change. Research design, data and methodology: This study selected the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement as a key methodology. Literature search used the following databases: Web of Science, Scopus, and Google Scholar. The quality assessment criteria for selected prior studies ranged from issues like design, sample size and the representativeness of the subjects, validity of measurements, and analytical strength. Results: The findings of this study indicates that there are four critical solutions for economic development triggers using ESG strategy, such as (1) ESG and Innovation-Driven Growth, (2) ESG and Human Capital Development, (3) ESG and Operational Efficiency, (4) ESG and Market Opportunities. This study insists that public-private partnerships are critical for enhancing sustainable economic development and meeting the needs of society. Conclusions: It is, therefore, important for governments and policymakers to play a critical role in setting the proper framework that allows for the uptake of ESG and an enabling environment for sustainable economic development.

16S rRNA 유전자 기반의 Pyrosequencing을 이용한 하수처리시설 생물반응기의 세균군집구조 분석 (Analysis of Bacterial Community Composition in Wastewater Treatment Bioreactors Using 16S rRNA Gene-Based Pyrosequencing)

  • 김택승;김한신;권순동;박희등
    • 미생물학회지
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    • 제46권4호
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    • pp.352-358
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    • 2010
  • 서로 다른 처리공정으로 운영되는 4개의 하수시설을 대상으로 16S rRNA 유전자 기반의 pyrosequencing을 이용해 활성슬러지 하수처리 생물반응기의 세균군집구조를 분석하였다. 활성 슬러지에는 Rhodocyclales, Burkholderiales, Sphingobacteriales, Myxococcales, Xanthomonadales, Acidobacteria group 4, Anaerolineales, Methylococcales, Nitrospirales, Planctomycetales 목에 속하는 염기서열이 전체의 54-68%를 차지해, 소수의 세균 분류군이 활성슬러지 세균군집의 대부분을 차지하고 있었다. 이들 소수 세균 분류군의 조성은 처리장별로 차이가 있었으며, 하수처리장의 운전조건 및 환경조건에 영향을 받는 것으로 추측되었다. 또한, 활성슬러지는 매우 다양한 세균 종을 가지는 것으로 관찰되었는데(Chao1 richness estimate: 1,374-2,902 operational taxonomic units), 대부분의 다양성은 희귀 종에 기인한 것으로 나타났다. 특히, 분리막으로 운영되는 하수처리시설에서 높은 다양성을 나타내었는데, 처리공정이 매우 긴 고형물체류시간으로 운영되어 느리게 성장하는 다양한 세균이 서식하는데 용이하기 때문인 것으로 판단되었다. High-throughput pyrosequencing 기술을 이용하여 활성슬러지 세균군집을 처리장별로 비교 분석한 본 연구는 향후 활성슬러지 미생물의 생태학적 특성을 보다 잘 이해하고 하수처리공정을 개선하는데 도움이 될 것이다.

자율주행을 위한 국내 ODD 분류 체계 연구 (A Study on Operational Design Domain Classification System of National for Autonomous Vehicle of Autonomous Vehicle)

  • 이지연;손승녀;조용성
    • 한국ITS학회 논문지
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    • 제22권2호
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    • pp.195-211
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    • 2023
  • 자율주행자동차(Automated Vehicle, AV)의 상용화를 위해서는 ADS의 운행가능영역(Operational Design Domain, ODD)이 명확하게 정의되어야 하며, AV 관련 이해관계자들이 ODD에 대해 모두가 동일한 기준을 가지고 동일한 수준으로 이해할 수 있도록 공통된 언어와 일관된 양식이 마련되어야 한다. 따라서, 국외에서는 표준화된 ODD 프레임워크를 제시하고, ODD를 기반으로 ADS 특정 기능을 평가할 수 있는 시나리오 개발에 박차를 가하고 있다. 하지만, ODD는 도로환경, 기상환경, 교통환경 등 해당 국가별 특성이 반영된 조건이 포함되기 때문에 국외에서 정의된 항목을 그대로 적용하는 것이 아니라, 그 항목의 의미를 명확히 이해하고 국내의 여건을 반영하여 이를 정합화할 필요가 있다. 따라서, 본 연구에서는 국제표준을 기반으로 국내 주행환경을 분석하여 ODD 분류 체계 국내 최적화를 수행하였으며, 개발된 국내 ODD 항목을 기반으로 현재 운영 중인 자율주행차 시범운행지구(서울 상암, 광주)의 주행환경을 조사하고 그 결과를 바탕으로 시험운행지구별 ODD의 범위를 비교하였다.