273 research outputs found

    The Meeting of Acquaintances: A Cost-efficient Authentication Scheme for Light-weight Objects with Transient Trust Level and Plurality Approach

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    Wireless sensor networks consist of a large number of distributed sensor nodes so that potential risks are becoming more and more unpredictable. The new entrants pose the potential risks when they move into the secure zone. To build a door wall that provides safe and secured for the system, many recent research works applied the initial authentication process. However, the majority of the previous articles only focused on the Central Authority (CA) since this leads to an increase in the computation cost and energy consumption for the specific cases on the Internet of Things (IoT). Hence, in this article, we will lessen the importance of these third parties through proposing an enhanced authentication mechanism that includes key management and evaluation based on the past interactions to assist the objects joining a secured area without any nearby CA. We refer to a mobility dataset from CRAWDAD collected at the University Politehnica of Bucharest and rebuild into a new random dataset larger than the old one. The new one is an input for a simulated authenticating algorithm to observe the communication cost and resource usage of devices. Our proposal helps the authenticating flexible, being strict with unknown devices into the secured zone. The threshold of maximum friends can modify based on the optimization of the symmetric-key algorithm to diminish communication costs (our experimental results compare to previous schemes less than 2000 bits) and raise flexibility in resource-constrained environments.Comment: 27 page

    Effects of Fertilizers on Biomass, Sugar Content and Ethanol Production of Sweet Sorghum

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    Sweet sorghum (Sorghum bicolor) is a promising alternative crop for bioethanol production in developing countries. However, to extend the cultivative area of this crop, it needs to develop an appropriate growing protocol for farmers. This chapter describes the examination of different doses of fertilizers combined with manure and micronutrients, in various applied times, on biomass, sugar content and ethanol production of sweet sorghum. It was observed that the application of 90 N + 90 P2O5 + 60 K2O provided maximum stem yield and optimum contents of sugar and ethanol yield, however nontreatment of any among P, P2O5 and K2O caused significant reduction of biomass and ethanol production. Higher fertilization >90 N may provide greater productivity of this crop but it may cause lodging and economic deficit for farmers in developing countries. It was also found that the applied times of fertilization should be at 3–4 to 7–8 leaf stage. In contrast, when the fertilization was as close to the flowering stage caused remarkable reduction of stem yield and ethanol production. The supplementation of (NH4)2MO7O2.4H2O at 5 kg/ha provided an increase of 10–12 tons/ha of stem yield and a remarkable enrichment of ethanol production. Findings of this study are useful for farmers and agricultural extensionists to promote biomass and ethanol productivity of this crop for bioethanol production. This research also highlights a greater possibility of exploiting sweet sorghum cultivation in infertile and hilly, abandoned areas for ethanol production

    Biological roles of momilactones: achievements, challenges, and promising approaches to exploit their beneficial properties

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    Momilactones are defined as every lactone derived from rice husk. To date, these compounds can only be naturally found in rice (Oryza lineage) and moss (Pseudoleskeella papillosa and Hypnum plumaeforme). Their basic structure refers to the (9β-H)-pimarane skeleton bearing a γ-butyrolactone. In this review, the beneficial properties of momilactones, especially momilactones A (MA) and B (MB), including allelopathy, antimicrobials, antioxidants, anti-chronic diseases, anti-inflammation, and anticancer, are highlighted. Additionally, the signaling roles of momilactones in the response of host plants against environmental stresses are discussed, raising the question of whether momilactones act as novel phytohormones that require further comprehensive clarification. In another aspect, we come up with promising approaches to the future exploitation of these valuable compounds based on the current knowledge of their bioactivity mechanisms, biosynthetic pathways, and isolation protocols. However, momilactone biosynthetic processes remain elusive. Moreover, challenges in researching these compounds are mainly due to difficulties in isolation procedures and the lack of commercial sources, which have been least improved over the last half-century. Accordingly, we propose promising strategies to address these present problems and promote the effectiveness of further research, including: i) to improve the efficiency of momilactone extraction and isolation from plant sources; ii) to increase momilactone production applying synthetic models; iii) to generate crops that accumulate greater momilactone contents through genetic engineering approaches; iv) to discover new applications that combine momilactones with other prospective substances for enhancing targeted biological properties and preventing undesirable impacts; and v) to employ smart farming for optimizing the application of momilactones, monitoring their levels, and promoting sustainable agriculture. This paper may provide valuable insights for future strategies, focusing on the exploitation of momilactones for human health-beneficial purposes and the development of green agriculture aligned with sustainable development targets
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