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The research paper delves into the importance of point cloud data obtained from 3D scanning technology ensuring quality control in industrial settings. It presents a new heuristic approach that utilizes the wavelet algorithm and other techniques to detect and characterize induced forming defects accurately. The proposed approach offers more flexibility, ease of use, and better results based on descriptive and prescriptive analyses from DRM. The results demonstrate that the wavelet algorithm was successful in identifying and characterizing forming defects in point cloud data. [ABSTRACT FROM AUTHOR]

Mass gathering has been identified as one of the causes of fast-spreading of COVID-19. Physical distancing practices and large gathering control in Malaysia and all over the world are likely to be continued until the end of the year, even after Movement Control Order (MCO) has been lifted. This has imposed event organizers to redesign their events into virtual events where attendees are to stay at their houses and meet with the host and other attendees virtually. However, certain types of educational events or activities such as practical and hands-on classes are not to be virtually conducted as it by nature carries a competency for the students. This paper evaluates the standard classroom layout by comparing with optimal layout based on circle packing problem (CPP) solution. CPP solution is used to optimize the physical distancing-constrained for the student seat layout as in it happens in real life. The findings can provide an effective exit strategy for Malaysia to deal with this COVID-19 pandemic or other pandemics in the future. [ABSTRACT FROM AUTHOR]

Neutron production with laser-driven neutron sources was demonstrated. We outline the basics of laser-driven neutron sources, highlight some fundamental advantages, and quantitatively compare the neutron production at the TRIDENT laser sources with the well-established LANSCE pulsed neutron spallation source. Ongoing efforts by our team to continue development of these sources, in particular the LANSCE-ina-box instrument, are described. The promise of ultra-intense lasers as drivers for brilliant, compact, and highly efficient particle accelerators portends driving next-generation neutron sources, potentially replacing in some cases much larger conventional accelerators. [ABSTRACT FROM AUTHOR]

This paper proposes advanced manufacturing method of adhesive assembly of multilayer devices with variable cross-section that allows expanding possibilities for the use of modern polymer composite materials (PCM) in the manufacture of products of aerospace and aviation industry. We investigated the interrelation between pressure of directional hot air flow and pore volume fraction in solidified material of multilayer device of adhesive assembly with variable cross-section during layer-by-layer application. The methodology of efficient control of pore content during adhesive assembly of devices is developed on the basis of the results of laboratory studies. [ABSTRACT FROM AUTHOR]

The complex oxides are very fascinating materials because of the interesting structures and wide variety of properties associated with them such as superconductors, ideal semiconductors, magnetic materials, catalysts, ferroelectrics, dielectrics, electrode materials for batteries, fuel cells and so on. The Structural and electronic properties of Lnn+1NinO2n+2 (Ln=La, Ce, Pr, Pm; n=3) are investigated by performing the full-potential linearized augmented plane wave method. The results related to La4Ni3O8 are in excellent agreement with the reported data. While, the results for Ce4Ni3O8, Pr4Ni3O8 and Pm4Ni3O8; are reported for the first time. We expect that the obtained results will be very useful for future experimental research. [ABSTRACT FROM AUTHOR]

Science instruments with large collecting areas that maintain dimensional stability, such as National Aeronautics and Space Administrations' (NASA) James Webb Space Telescope (JWST) and Wide Field Infra-red Space Telescope (WFIRST), and help achieve next generation science advancements. Composite materials often used for science applications include high modulus fibers in cyanate ester matrices to result in dimensionally stable structures with low contamination. Hand lay-up fabrication is the most common approach for science instrument structures. Automated Fiber Placement (AFP) using intermediate modulus fibers is commonplace in aircraft production reducing manufacturing time and increasing quality and consistency. AFP manufacturing for future large science instruments can similarly reduce costs and increase reliability. However, high modulus fibers are more prone to damage than intermediate modulus fibers. This study investigates the manufacturing viability of Tencate provided M55J/RS3C (Tencate) slit tape material using AFP processing. NASA Langley Research Center (LaRC) manufactured hand layup and AFP lay-up laminates under room temperature for initial trials, Marshall Space Flight Center (MSFC) manufactured AFP laminates under room temperature and elevated temperature conditions to evaluate processing affects. Goddard Space Flight Center (GSFC) tested and evaluated tension and Coefficient of Thermal Expansion (CTE) properties by hand lay-up and AFP slit tape automated manufacturing for large science applications. These results show processing material warm reduces process induced fiber damage; leading to stiffness and CTE properties consistent with hand lay-up, while observing a slight degradation in tensile strength. [ABSTRACT FROM AUTHOR]

The ubiquitous usage of polymer matrix composites in aerospace, automobile, and other industries necessitates a comprehensive understanding of manufacturing defects such as delamination, debonding and wrinkling. Investigating the movement of ply interfaces during manufacturing will help understand the fundamental phenomenon that leads to the formation of processing-induced defects. In this paper, the interfacial movement in carbon fiber laminate is characterized in-situ during different stages of curing in a specially designed autoclave with viewports. Plies are laidup on a cylindrical rod placed on a flat plate to simulate the maximum movement of plies, resulting in the formation of wrinkles. Ply-movement is measured in-situ using Digital Image Correlation (DIC) during the cure cycle. In addition, the resulting defects are characterized post cure using XRay Computed Tomography (CT). Preliminary results demonstrate the effectiveness of this approach in examining defects like wrinkles. Results show the formation of a wrinkle due to the out of plane ply movement (0.65 mm) and the evolution of the wrinkle through the curing cycle. [ABSTRACT FROM AUTHOR]

The advent of Automated Fiber Placement (AFP) systems have aided the rapid manufacturing of composite aerospace structures. One of the challenges that AFP systems pose is the uniformity of the deposited prepreg tape layers, which complicates detection of laps, gaps, overlaps and twists. The current detection method used in industry involves halting fabrication and performing a time consuming, visual inspection of each tape layer. Typical AFP systems use a quartz lamp to heat the base layer to make the surface tacky as it deposits another tape layer. The innovation proposed in this paper is to use the preheated base layer as a through-transmission heat source for inspecting the newly added tape layer in situ using a thermographic camera mounted on to the AFP hardware. Such a system would not only increase manufacturing throughput by reducing inspection times, but it would also aid in process development for new structural designs or material systems by providing data on as-built parts. To this end, a small thermal camera was mounted onto an AFP robotic research platform at NASA, and thermal data was collected during typical and experimental layup operations. The data was post processed to reveal defects such as tow overlap/gap, wrinkling, and peel-up. Defects that would have been impossible to detect visually were also discovered in the data, such as poor/loss of adhesion between plies and the effects of vacuum debulking. This paper will cover the results of our experiments, and the plans for future versions of this inspection system. [ABSTRACT FROM AUTHOR]

Automated Fiber Placement (AFP), a major composite manufacturing process, can result in many defects during the layup process that often require manual corrective action to produce a part with acceptable quality. These defects are the main limitation of the technology and can be hard to categorize or define in many situations. This paper provides a thorough definition and classification of all AFP defects. This effort constitutes a comprehensive and extensive library relevant to AFP defects. The defects selected and defined in this work are based on understanding and experience from the manufacture and research of advanced composite structure. Proper classification of these defects required an in-depth literature review and consideration of various viewpoints ranging from designers, manufacturers, analysts, and inspection professionals. Collectively, these sources were utilized to develop the most accurate view of each of the individual defect types. The results are presented as identity cards for each defect type, intended to provide researchers and the manufacturing industry a clear understanding of the (1) cause, (2) anticipation, (3) existence, (4) significance, and (5) progression of the defined AFP defects. The link between AFP defects and process planning, layup strategies, and machining was also investigated. Categorization of all important automated fiber placement defects is presented. [ABSTRACT FROM AUTHOR]

This work formulates an automated fiber placement (AFP) defects assessment framework. Such framework assumes AFP manufacturing processes are able to identify manufacturing defects via automated inspection systems and intends to provide rapid analysis tools to create a defect assessment loop. The defect assessment loop defines an automated analysis process during AFP manufacturing to minimize the number of manual repairs on the part, thus accelerating AFP manufacturing of composite structures. This defects assessment loop employs automated inspection data to evaluate the influence of encountered AFP defects on a ply-by-ply basis. Structural evaluation is based on strength criteria using local-global finite element models. Local models affect the global part model via material property reductions. Schemes to reduce material properties using the local models are the main enablers of this framework's automated assessment capability. Finally, we discuss the main technical challenges to realize the feasibility of this framework. [ABSTRACT FROM AUTHOR]

There has been a huge uptake by industry groups to adapt automated fibre placement (AFP) based manufacturing due to it's high level of productivity, accuracy and reliability. The AFP technology merges through several manufacturing stages like cutting, curing and consolidation. The high level of productivity, accuracy and reliability in automated fibre placement (AFP) have opened new markets and applications for high value laminated composite structures. However, from a system engineering perspective, manufacturing of composites using AFP is a complex, high-dimensional nonlinear multivariable process that involves large number of variables and parameters. The quality and integrity of the structure is critically dependent on the choice of these parameters, which are typically extracted by conducting several lab-based experiments with varied processing parameters. Appropriate selection of these parameters would provide optimal result. Artificial neural network (ANN), a Machine Learning technique has been gaining popularity in various engineering applications including prediction, control, fault diagnosis etc. In this study, a multi-layer perceptron based ANN has been trained to accurately represent the complex relationship between various processing parameters in AFP that would give optimised outcome. The ANN model will subsequently be used to obtain the optimised parameters that can be integrated in AFP based manufacturing of laminated composite structures. [ABSTRACT FROM AUTHOR]

Soil surface roughness (SSR) is a critical variable for retrieving soil moisture using microwave remote sensing model. To quantify SSR, the data of soil surface microtopography (SSM) is needed. SSM is the micro elevation of soil surface. The methods of microtopography measurement mainly include the pin meter and profile meter, photography, laser scanning. A method of laser scanning is considered the accurate measurement of microtopography in these methods, but need a very bulky device for field survey. It is necessary to introduce a new device which is precise and portable for microtopographic measurement. In this study, two devices, an Instantaneous-Profile Laser Scanner (IPLS) and a Structured Light 3D Scanner (SLS), would be investigated in the measuring of SSM. The portability of device, the capability of data acquiring, and the precision of two methods were compared with an experiment. With a practical measuring process, it was found that the portability of structured light 3D sensor is excellent. For the capability of acquiring data, the Instantaneous-Profile Laser Scanner is weak than structured light 3D sensor because of view angle of the camera, it cannot deal with the shadow effect very well. For the precision, the result showed that the precision of structured light 3D sensor is a little less than laser scanning because of the limitation of its spatial resolution. All of above, it is believed that structured light range image technology would be very useful on measurement of SSM, and structured light 3D sensor would be very popular in soil roughness measurement. [ABSTRACT FROM PUBLISHER]

A computational model for the interrelated phenomena in the process of vacuum arc remelting is analyzed and adjusted of optimal accuracy and computation time. The decision steps in this case study are offered as an example how the coupling in models of similar processes can be addressed. Results show dominance of the electromagnetic forces over buoyancy and inertia for the investigated process conditions. [ABSTRACT FROM AUTHOR]