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- Jiang, Yuning, 1993-, et al.
(författare)
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Model-Based Cybersecurity Analysis : Extending Enterprise Modeling to Critical Infrastructure Cybersecurity
- 2023
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Ingår i: Business & Information Systems Engineering. - : Springer. - 2363-7005 .- 1867-0202. ; 65:6, s. 643-676
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Tidskriftsartikel (refereegranskat)abstract
- Critical infrastructure (CIs) such as power gridslink a plethora of physical components from many differentvendors to the software systems that control them. Thesesystems are constantly threatened by sophisticated cyberattacks. The need to improve the cybersecurity of such CIs,through holistic system modeling and vulnerability analysis,cannot be overstated. This is challenging since a CIincorporates complex data from multiple interconnectedphysical and computation systems. Meanwhile, exploitingvulnerabilities in different information technology (IT) andoperational technology (OT) systems leads to variouscascading effects due to interconnections between systems.The paper investigates the use of a comprehensive taxonomyto model such interconnections and the implieddependencies within complex CIs, bridging the knowledgegap between IT security and OT security. The complexityof CI dependence analysis is harnessed by partitioningcomplicated dependencies into cyber and cyber-physicalfunctional dependencies. These defined functionaldependencies further support cascade modeling for vulnerabilityseverity assessment and identification of criticalcomponents in a complex system. On top of the proposedtaxonomy, the paper further suggests power-grid referencemodels that enhance the reproducibility and applicability ofthe proposed method. The methodology followed wasdesign science research (DSR) to support the designing andvalidation of the proposed artifacts. More specifically, thestructural, functional adequacy, compatibility, and coveragecharacteristics of the proposed artifacts are evaluatedthrough a three-fold validation (two case studies and expertinterviews). The first study uses two instantiated powergridmodels extracted from existing architectures andframeworks like the IEC 62351 series. The second studyinvolves a real-world municipal power grid. © 2023, The Author(s).
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| 2. |
- Xiong, Shaobing, et al.
(författare)
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Revealing buried heterointerface energetics towards highly efficient perovskite solar cells
- 2023
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Ingår i: Nano Energy. - : ELSEVIER. - 2211-2855 .- 2211-3282. ; 109
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Tidskriftsartikel (refereegranskat)abstract
- The heterointerfaces of charge-selective contacts are crucial in determining efficiency and stability of perovskite optoelectronic devices, where the fundamental knowledge of the buried heterointerface between perovskite and bottom charge transport layer is less well understood compared to the top interface. Herein, we systematically investigate the energetics at the perovskite/SnO2 buried heterointerface for an n-i-p perovskite solar cell (PSC) and the perovskite/PEDOT:PSS buried heterointerface for a p-i-n one, respectively. In contrast to previous cognitions, we discover a perovskite transition phase at the buried interface region that originates from the chemical bonding interaction with the bottom charge transport layer. The transition phase causes an energy level barrier and induces defects, impeding charge transport across the heterointerface. These detrimental effects trigger significant nonradiative recombination and limit the attainable device photovoltage. We then develop the energetic models that describe such buried heterointerfaces. Moreover, we further test the proposed model -derived mechanisms via inserting a thin polyvinyl alcohol layer into the buried heterointerfaces of the de-vices. We demonstrate that chemical interactions and formation of the perovskite transition phase at the buried heterointerface thereby are fully restrained, leading to a diminished electron extraction barrier and improved charge transport. As a result, significant increases in open-circuit voltage and fill factor of the devices are ach-ieved. These results will help guide future efforts on developing suitable buried heterointerfaces for superior performance of perovskite optoelectronics.
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