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Advancing sustainability and efficiency in supply chains: insights from the special issue on sustainable supply chain and lean manufacturing [Editorial]
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High Speed Camera Tests - ERICE
No full textThis item contains the data from the High speed camera tests for ERICE project based on conditions 1 and 2 of the test matrix. Data includes: 1) High Speed camera videos for two test conditions (x2) - '.avi' format 2) Labview files (x2) - '.lvm' format (read with MS Excel) 3) README txt file (x1) - explaining the headers for the labview data and the instrumentation involved. Test 1 refers to the 50k RPM condition from the test matrix and Test 2 refers to the 60k RPM condition from the test matrix
HAZ effects in hot-rolled dual-phase steel during flash butt welding of wheel rims
Get PDFThe embrittlement and softening behavior in simulated heat-affected zones (HAZ) of a newly designed dual-phase DP680 steel for wheel rim applications with different flash allowances were investigated to determine weldability, and offer valuable information for the steel design and its subsequent flash butt welding (FBW). The characterization of microstructure and mechanical performance for the simulated HAZ was conducted by means of optical microscopy, scanning electron microscopy, electron backscatter diffraction, hardness distribution, and Charpy V-notch (CVN) values at selected temperatures. The investigation demonstrates that the toughness of coarse-grained HAZ was kept at an average level of 25.3 J when the prior austenite grain size was controlled to 60.54 μm at a flash allowance of 14 mm (equivalent to heat input of 15.14 kJ/cm based on real welding process), which exhibits the worst toughness when the flash allowance was changed from 4 to 14 mm. Further, with a higher martensite fraction (> 30 pct) in base material (BM), the softening occurs in inter-critical HAZ (ICHAZ) instead of sub-critical HAZ since most of martensite in ICHAZ has decomposed, and the rest ferrite and newly formed bainite with remaining martensite reduce the hardness to a larger extent compared to SCHAZ, whose martensite has only partly decomposed. Even if the softening degree is up to 21.6 pct compared to the BM (average 233 HV0.5), the work hardening during a series of forming processes after FBW has alleviated the softening evidently (work hardening degree > 10 pct). However, the failure location is still in ICHAZ after forming extension which has been confirmed in practical applications of DP680 FBW and subsequent forming processes.Metallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Scienc
Metal 3D-printing for repair of steel structures
Get PDFThis work employs an innovative technique, wire arc additive manufacturing (WAAM) which is a type of directed energy deposition, for fatigue strengthening of cracked steel components. Different steel plates with a central crack were tested under high-cycle fatigue loading regime, including a reference plate, a plate repaired by WAAM with as-deposited profile, and a plate repaired by WAAM and subsequently machined to reduce stress concentration factors. Corresponding finite element simulation was conducted to provide a better understanding on the mechanism of WAAM-repair. The existing central crack in the reference plate propagated and led to a rupture after 0.94 million cycles, while those in the two WAAM-repaired plates did not propagate, due to the increased net cross-section and the compressive stresses induced by the depositing process. However, in the second plate, a new crack initiated at the root of WAAM profile as a result of local stress concentration, and the fatigue life reached 2.2 million cycles (2.3 times as the reference plate). The third plate, on the other hand, survived more than 9 million fatigue cycles with no visible degradation, thanks to its smooth machined profile. The findings of this work indicate that WAAM repair shows great potential as a technique to address fatigue-related damages in steel structures.10th Eurosteel Conference 202
Prognostic and health management of critical aircraft systems and components: an overview
Get PDFThis article belongs to the Special Issue Feature Papers in Fault Diagnosis & Sensors 2023Prognostic and health management (PHM) plays a vital role in ensuring the safety and reliability of aircraft systems. The process entails the proactive surveillance and evaluation of the state and functional effectiveness of crucial subsystems. The principal aim of PHM is to predict the remaining useful life (RUL) of subsystems and proactively mitigate future breakdowns in order to minimize consequences. The achievement of this objective is helped by employing predictive modeling techniques and doing real-time data analysis. The incorporation of prognostic methodologies is of utmost importance in the execution of condition-based maintenance (CBM), a strategic approach that emphasizes the prioritization of repairing components that have experienced quantifiable damage. Multiple methodologies are employed to support the advancement of prognostics for aviation systems, encompassing physics-based modeling, data-driven techniques, and hybrid prognosis. These methodologies enable the prediction and mitigation of failures by identifying relevant health indicators. Despite the promising outcomes in the aviation sector pertaining to the implementation of PHM, there exists a deficiency in the research concerning the efficient integration of hybrid PHM applications. The primary aim of this paper is to provide a thorough analysis of the current state of research advancements in prognostics for aircraft systems, with a specific focus on prominent algorithms and their practical applications and challenges. The paper concludes by providing a detailed analysis of prospective directions for future research within the field.European Union funding: 955681Sensor
Field phenotyping for African crops: overview and perspectives
Get PDFImprovements in crop productivity are required to meet the dietary demands of the rapidly-increasing African population. The development of key staple crop cultivars that are high-yielding and resilient to biotic and abiotic stresses is essential. To contribute to this objective, high-throughput plant phenotyping approaches are important enablers for the African plant science community to measure complex quantitative phenotypes and to establish the genetic basis of agriculturally relevant traits. These advances will facilitate the screening of germplasm for optimum performance and adaptation to low-input agriculture and resource-constrained environments. Increasing the capacity to investigate plant function and structure through non-invasive technologies is an effective strategy to aid plant breeding and additionally may contribute to precision agriculture. However, despite the significant global advances in basic knowledge and sensor technology for plant phenotyping, Africa still lags behind in the development and implementation of these systems due to several practical, financial, geographical and political barriers. Currently, field phenotyping is mostly carried out by manual methods that are prone to error, costly, labor-intensive and may come with adverse economic implications. Therefore, improvements in advanced field phenotyping capabilities and appropriate implementation are key factors for success in modern breeding and agricultural monitoring. In this review, we provide an overview of the current state of field phenotyping and the challenges limiting its implementation in some African countries. We suggest that the lack of appropriate field phenotyping infrastructures is impeding the development of improved crop cultivars and will have a detrimental impact on the agricultural sector and on food security. We highlight the prospects for integrating emerging and advanced low-cost phenotyping technologies into breeding protocols and characterizing crop responses to environmental challenges in field experimentation. Finally, we explore strategies for overcoming the barriers and maximizing the full potential of emerging field phenotyping technologies in African agriculture. This review paper will open new windows and provide new perspectives for breeders and the entire plant science community in Africa.BBSRC: BB/P016855/1Frontiers in Plant Scienc
Metal(loid)s concentration with humic acid in <1 and >10 year old landfills
No full textMetal(loid)s mobilised from landfill samples at differing pH and humic acid concentrations. The datasets provide metal(loid) concentrations for samples 10 years old
Real-time motion planning for quadcopter using adaptive spherical expansion and sequential convex optimization
Get PDFThis paper introduces the Adaptive Spherical Expansion and Sequential Convex Programming (ASE-SCP) as a real-time motion planning algorithm. ASE-SCP algorithm is an improved version of the Spherical Expansion and Sequential Convex Programming (SE-SCP) algorithm in terms of computational speed. ASE-SCP is a hybrid real-time motion planning algorithm which combines the advantages of the Adaptive Spherical Expansion, such as approaching the neighborhood of the global optimal path, and the quick convergence ability of the Sequential Convex Programming. The ASE-SCP algorithm first finds a collision-free path using the adaptive spherical expansion approach. After finding a feasible path from the start point to the target point, the feasible path is re-optimized (tuned) using sequential convex optimization to find the suboptimal path. ASE-SCP Algorithm is applied to a quadcopter model to demonstrate its applicability.AIAA SciTech Forum 202
Ergosterol extraction: a comparison of methodologies
Get PDFErgosterol is a component of the cell membrane of mycorrhizal fungi and is frequently used to quantify their biomass. Arbuscular mycorrhizal (AM) fungi and ectomycorrhizal (ECM) fungi establish a symbiotic relationship with a respective host plant. Several methods are currently employed for quantification of ergosterol; however, these utilise a series of potentially hazardous chemicals with varying exposure times to the user. The present comparative study aims to ascertain the most reliable method to extract ergosterol whilst limiting hazard exposure to the user. Chloroform, cyclohexane, methanol and methanol hydroxide extraction protocols were applied to a total of 300 samples of root samples and a further 300 growth substrate samples across all protocols. Extracts were analysed via HPLC methodologies. Chromagraphic analysis showed chloroform-based extraction procedures produced a consistently higher concentration of ergosterol in both root and growth substrate samples. Methanol hydroxide, without the addition of cyclohexane, produced a very low concentration of ergosterol, with a reduction of quantified ergosterol of between 80 and 92 % compared to chloroform extractions. Hazard exposure was greatly reduced following the chloroform extraction protocol when compared with other extraction procedures.Access Microbiolog
Milestones in autonomous driving and intelligent vehicles - Part 1: control, computing system design, communication, HD map, testing, and human behaviors
Get PDFInterest in autonomous driving (AD) and intelligent vehicles (IVs) is growing at a rapid pace due to the convenience, safety, and economic benefits. Although a number of surveys have reviewed research achievements in this field, they are still limited in specific tasks and lack systematic summaries and research directions in the future. Our work is divided into three independent articles and the first part is a survey of surveys (SoS) for total technologies of AD and IVs that involves the history, summarizes the milestones, and provides the perspectives, ethics, and future research directions. This is the second part (Part 1 for this technical survey) to review the development of control, computing system design, communication, high-definition map (HD map), testing, and human behaviors in IVs. In addition, the third part (Part 2 for this technical survey) is to review the perception and planning sections. The objective of this article is to involve all the sections of AD, summarize the latest technical milestones, and guide abecedarians to quickly understand the development of AD and IVs. Combining the SoS and Part 2, we anticipate that this work will bring novel and diverse insights to researchers and abecedarians, and serve as a bridge between past and future.IEEE Transactions on Systems, Man, and Cybernetics: System