14 research outputs found

    Development of methods for identifying an appropriate benchmarking peer to establish information security policy

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    Benchmarking methodology provides organizations with appropriate information security policy. However, selecting an appropriate organization as a benchmarking peer can be a challenge due to firms’ heterogeneous implementation and usage of information systems. Our goal is to develop and propose methods to appropriately identify a benchmarking peer organization by incorporating machine learning methods and mathematics set theory. We incorporate vague soft set, entropy, dynamic time warping, and Gaussian process. We use log data from information security management systems in multiple companies to validate our methods. Our experimental results indicate that the combined use of Gaussian process, vague soft set, and dynamic time warping can be more effective in identifying an appropriate benchmarking peer than conventional machine learning methods

    Benchmarking Methodology Development for Establishing Information System Security Policy: A Design Science Approach

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    Benchmarking methodology can provide organizations with a way of choosing an appropriate ISSP by referring to others in the industry. However, selecting a proper benchmarking target in establishing of information system security policy is a challenge. This paper proposes an artifact to select a target organization by quantitatively measuring the similarity of organizations’ systems. Our proposed artifact includes required formulas and an algorithm which compute the similarities. The artifact is based on moment generating function with probabilistic distribution through moment method and generalized method of moment. We expect the artifact may resolve the challenge of selecting a target organization by increasing the accuracy of similarity identification

    Critical review of bioelectrochemical systems integrated with membrane-based technologies for desalination, energy self-sufficiency, and high-efficiency water and wastewater treatment

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    Bioelectrochemical systems (BESs) are versatile electrochemical technologies that use microbial catalysts for simultaneously harvesting energy and treating wastewater. However, there is a consensus that practical energy applications and clean water production remain technically challenging for stand-alone BESs. To address these technological challenges, membrane-based technologies for water/wastewater treatment and energy production, such as electrodialysis, forward osmosis, reverse electrodialysis, and pressurized filtration (e.g., ultrafiltration), have been integrated into BESs. This integration has created new systems including microbial desalination cells, osmotic microbial fuel cells, pressurized filtration-microbial fuel cells, and microbial reverse-electrodialysis cells. This article aims to provide a comprehensive review on the recent progress in BESs integrated with membrane-based technologies, discuss advantages and limitations, and present outlooks toward further development of these technologies

    Enhancing the Dye-Rejection Efficiencies and Stability of Graphene Oxide-Based Nanofiltration Membranes via Divalent Cation Intercalation and Mild Reduction

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    Laminar graphene oxide (GO) membranes have demonstrated great potential as next-generation water-treatment membranes because of their outstanding performance and physicochemical properties. However, solute rejection and stability deterioration in aqueous solutions, which are caused by enlarged nanochannels due to hydration and swelling, are regarded as serious issues in the use of GO membranes. In this study, we attempt to use the crosslinking of divalent cations to improve resistance against swelling in partially reduced GO membranes. The partially reduced GO membranes intercalated by divalent cations (i.e., Mg2+) exhibited improved dye-rejection efficiencies of up to 98.40%, 98.88%, and 86.41% for methyl orange, methylene blue, and rhodamine B, respectively. In addition, it was confirmed that divalent cation crosslinking and partial reduction could strengthen mechanical stability during testing under harsh aqueous conditions (i.e., strong sonication)

    Antiviral Nanomaterials for Designing Mixed Matrix Membranes

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    Membranes are helpful tools to prevent airborne and waterborne pathogenic microorganisms, including viruses and bacteria. A membrane filter can physically separate pathogens from air or water. Moreover, incorporating antiviral and antibacterial nanoparticles into the matrix of membrane filters can render composite structures capable of killing pathogenic viruses and bacteria. Such membranes incorporated with antiviral and antibacterial nanoparticles have a great potential for being applied in various application scenarios. Therefore, in this perspective article, we attempt to explore the fundamental mechanisms and recent progress of designing antiviral membrane filters, challenges to be addressed, and outlook

    Analysis of circulating-microRNA expression in lactating Holstein cows under summer heat stress.

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    Korean peninsula weather is rapidly becoming subtropical due to global warming. In summer 2018, South Korea experienced the highest temperatures since the meteorological observations recorded in 1907. Heat stress has a negative effect on Holstein cows, the most popular breed of dairy cattle in South Korea, which is susceptible to heat. To examine physiological changes in dairy cows under heat stress conditions, we analyzed the profiles circulating microRNAs isolated from whole blood samples collected under heat stress and non-heat stress conditions using small RNA sequencing. We compared the expression profiles in lactating cows under heat stress and non-heat stress conditions to understand the regulation of biological processes in heat-stressed cows. Moreover, we measured several heat stress indicators, such as rectal temperature, milk yield, and average daily gain. All these assessments showed that pregnant cows were more susceptible to heat stress than non-pregnant cows. In addition, we found the differential expression of 11 miRNAs (bta-miR-19a, bta-miR-19b, bta-miR-30a-5p, and several from the bta-miR-2284 family) in both pregnant and non-pregnant cows under heat stress conditions. In target gene prediction and gene set enrichment analysis, these miRNAs were found to be associated with the cytoskeleton, cell junction, vasculogenesis, cell proliferation, ATP synthesis, oxidative stress, and immune responses involved in heat response. These miRNAs can be used as potential biomarkers for heat stress

    Transition metal/carbon nanoparticle composite catalysts as platinum substitutes for bioelectrochemical hydrogen production using microbial electrolysis cells

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    Various metal nanoparticle catalysts supported on Vulcan XC-72 and carbon-nanomaterial-based catalysts were fabricated and compared and assessed as substitutes of platinum in microbial electrolysis cells (MECs). The metal-nanoparticle-loaded cathodes exhibited relatively better hydrogen production and electrochemical properties than cathodes coated with carbon nanoparticles (CNPs) and carbon nanotubes (CNTs) did. Catalysts containing Pt (alone or mixed with other metals) most effectively produced hydrogen in terms of overall conversion efficiency, followed by Ni alone or combined with other metals in the order: Pt/C (80.6%) > PtNi/C (76.8%) > PtCu/C (72.6%) > Ni/C (73.0%) > Cu/C (65.8%) > CNPs (47.0%) > CNTs (38.9%) > plain carbon felt (38.7%). Further, in terms of long-term catalytic stability, Ni-based catalysts degraded to a lesser extent over time than did the Cu/C catalyst (which showed the maximum degradation). Overall, the hydrogen generation efficiency, catalyst stability, and current density of the Ni-based catalysts were almost comparable to those of Pt catalysts. Thus, Ni is an effective and inexpensive alternative to Pt catalysts for hydrogen production by MECs

    Recent Progress in One- and Two-Dimensional Nanomaterial-Based Electro-Responsive Membranes: Versatile and Smart Applications from Fouling Mitigation to Tuning Mass Transport

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    Membrane technologies are playing an ever-important role in the field of water treatment since water reuse and desalination were put in place as alternative water resources to alleviate the global water crisis. Recently, membranes are becoming more versatile and powerful with upgraded electroconductive capabilities, owing to the development of novel materials (e.g., carbon nanotubes and graphene) with dual properties for assembling into membranes and exerting electrochemical activities. Novel nanomaterial-based electrically responsive membranes have been employed with promising results for mitigating membrane fouling, enhancing membrane separation performance and self-cleaning ability, controlling membrane wettability, etc. In this article, recent progress in novel-nanomaterial-based electrically responsive membranes for application in the field of water purification are provided. Thereafter, several critical drawbacks and future outlooks are discussed
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