A computerised data handling procedure for defect detection and analysis for large area substrates manufactured by roll-to-roll process

The development of optical on-line/in-process surface inspection and characterisation systems for flexible roll to roll (R2R) thin film barriers used for photo-voltaic (PV) modules is a core research goal for the EU funded NanoMend project. Micro and nano scale defects in the ALD (atomic layer deposition) Al2O3 barrier coating produced by R2R techniques can affect the PV module efficiency and lifespan. The presence of defects has been shown to have a clear correlation with the water-vapour-transmission-rate (WVTR). Hence, in order to improve the PV cell performance and lifespan the barrier film layer must prevent water vapour ingress. One of the main challenges for the application of in process metrology is how to assess large and multiple measurement data sets obtained from an in process optical instrument. Measuring the surface topography over large area substrates (approximately 500 mm substrate width) with a limited field-of-view (FOV) of the optical instrument will produce hundreds/thousands of measurement files. Assessing each file individually to find and analyse defects manually is time consuming and impractical. This paper reports the basis of a computerised solution to assess these files by monitoring and extracting areal surface topography parameters. Comparing parameter values to an experimentally determined threshold value, obtained from extensive lab-based measurement of Al2O3 ALD coated films, can indicate the existence of the defects within a given FOV. This process can be repeated automatically for chosen parameters and the existence of defects can be indicated for the entire set of measurement files spontaneously without interaction from the inspector. A running defect log and defect statistics associated with the captured set of data files can be generated. This paper outlines the implementation of the auto-defect logging using advanced areal parameters, and its application in a proof of concept system at the Center for Process Innovation (UK) is discussed

Characterisation Platform For Surface Metrology

The measurement and characterisation of surface texture are the most critical factors and important functionality indicators.The real surfaces is continuous, but a discrete data set is acquired by any metrology instrumentation. After a series of processes of the finite digital sample, the parameters, which are the link betweenthe surface texture, the functionality excepted and the manufacturing process, will be calculated for the surface characterisation. This platform is designed to realize the analysis and processes for the surface characterisation

Building a Flexible Surface Characterisation System Architecture

Surface characterisation system needs to be updated constantly with the emergence of new algorithms and methods in the field of surface metrology. As function modules in current surface characterisation system are tightly coupled together, it is not conducive to the reuse of function modules and innovation of overall system. A lot of redundant and duplicate works have been done in present characterisation systems, and they will be done again when building a new characterisation system. In order to improve the reusability of function modules and facilitate system extension, this paper presents a flexible architecture for such surface characterisation systems by employing component based development technologies. Function components will be separated from system framework and implemented independently, so that the overall system is constructed by gluing these function components together

Construct Surface Characterization System by Assembling Functional Components Dynamically

Surface characterization of manufactured components is regarded as an important process to figure out surface features, which are closely related to the manufacture process and will affect their functionality. Due to the complicated computation, the actual operations are mostly completed by the aid of surface characterization software. Nowadays, these systems are mainly exploited by instrument companies and embedded in surface measurement instruments. Although it is convenient for users to evaluate surfaces straightforwardly after measurement, the results are usually incomparable with those from other surface instruments because of the different characterization systems. Moreover, the system evolution will cost too much due to the lack of flexibility and extendibility. This paper presents a component based architecture which facilitates the system construction by assembling functional components dynamically

The Development of a Flexible Characterisation System for Surface Metrology

Surface texture and its measurement are becoming more and more increasingly important in the field of high precision engineering and nano-technology. It is a significant and efficient way to predict the functional performance of an engineering product by characterising its surface. As the extraction and evaluation of surfaces features not only relies on analysis algorithms but also measurement techniques, most of surface characterisation software systems are embedded in the measurement instruments. At present, even though a series of Geometrical Product Specification (GPS) standards are released to guide the procedure of surface characterisation, there are no software systems give a fully support of them. As a consequence, evaluation results from different systems are incomparable, even worse, conflict with each other. Surface characterisation system needs to be updated constantly with the emergence of new algorithms and methods. However, the lack of good extensibility, reusability and maintainability is a serious obstacle to the innovation of existing surface characterisation systems. As functional modules in current surface characterisation systems are tightly coupled together, it is not conducive to the reuse of function modules and innovation of overall system. A lot of redundant and duplicate works have been raised in either enhancing present characterisation systems or building a new characterisation system. To improve the reusability of function modules and facilitate system extension, this research aims to establish a flexible surface characterisation system with an open architecture. By employing component based development technologies, the overall characterisation system is constructed by gluing various functional components together instead of being created from scratch. Each analysis algorithm or method is implemented as an independent functional component, which is separated from the system framework. And also it can be easily reused by other characterisation systems as an executable chunk. Any system functional components can be developed or maintained independently by different organisation as long as they comply with predefined protocols (interfaces). This thesis proposed a novel surface characterisation system, which can be reconfigured as end users‘ expectation at any time even when it has been installed and deployed already. Functional components can be added, removed or replaced dynamically without affecting other parts of the system. Furthermore, the system is flexible such that researchers and developers can concentrate on characterisation algorithms and methods themselves, and then develop their own functional components which can be easily added to this system

An adaptive system framework for surface characterisation.

Surface features have been recognised to be significant in many fields and the characterisation techniques are being constantly improved. The surface characterisation systems are developed by various instrument companies and institutions. However, the lack of good extensibility, reusability and maintainability is a serious obstacle to the system innovation. Component based software development offers a promising solution to the surface characterisation system with better extendibility and maintainability. This paper presents an overview of surface characterisation techniques, analyzes current surface characterisation systems, and then proposes a component based architecture for the surface characterisation system

A Host System for Form Tolerance Specification in the Next-generation GPS based on AutoCAD

Geometrical specification is the bridge to link function, design, manufacture and verification together for a product. The next-generation GPS utilizes duality principle to tightly combine specification and verification of a geometrical product, and to ensure its desired intention (functional requirements). This makes the geometrical specification of a product complete and unambiguous. The geometrical specification system prevailing currently is designed on the basis of traditional rules so that it is not consistent with the next-generation GPS. This paper presents a host system for form tolerance specification in framework of the next-generation GPS, which is built based on AutoCAD200

The role of short-chain fatty acids in central nervous system diseases: A bibliometric and visualized analysis with future directions

Background: Short-chain fatty acids (SCFAs) are thought to play a key role in the microbe-gut-brain axis and involve in the pathogenesis of a variety of neurological diseases. This study aimed to identify research hotspots and evolution trends in SCFAs in central nervous diseases (CNS) and examine current research trends. Methods: The bibliometric analysis was performed using CiteSpace, and the results were visualized via network maps. Results: From 2002 to 2022, 480 publications in the database met the criteria. On the country level, China produced the highest number of publications, while the United States had the highest centrality. On the institutional level, University College Cork contributed to the most publications, and John F. Cryan from this university was the key researcher with considerable academic influence. The article, the role of short-chain fatty acids in microbiota-gut-brain, written by Boushra Dalile et al., in 2019 was the most cited article. Furthermore, the journal Nutrients had the maximum number of publications, while Plos One was the most cited journal. “Gut microbiome”, “SCFAs”, and “central nervous system” were the three most frequent keywords. Among them, SCFAs had the highest centrality. “Animal model” was the keyword with the highest burst strength, with the latest burst keywords being “social behavior”, “pathogenesis”, and “insulin sensitive”. In addition, the research topics on SCFAs in CNS diseases from 2002 to 2022 mainly focused on following aspects: SCFAs plays a key role in microbe-gut-brain crosstalk; The classification and definition of SCFAs in the field of CNS; Several CNS diseases that are closely related to SCFAs research; Mechanism and translational studies of SCFAs in the CNS diseases. And the hotspots over the past 5 years have gradually increased the attention to the therapeutic potential of SCFAs in the CNS diseases. Conclusion: The research of SCFAs in CNS diseases is attracting growing attention. However, there is a lack of cooperation between countries and institutions, and additional measures are required to promote cooperation. The current evidence for an association between SCFAs and CNS diseases is preliminary and more work is needed to pinpoint the precise mechanism. Moreover, large-scale clinical trials are needed in the future to define the therapeutic potential of SCFAs in CNS diseases

A Ratiometric Fluorescent Bioprobe Based on Carbon Dots and Acridone Derivate for Signal Amplification Detection Exosomal microRNA

Recently, sensitive and selective detection of exosomal microRNAs (miRNAs) has been garnering significant attention, because it is related to many complex diseases, including cancer. Herein, we report a ratiometric fluorescent bioprobe based on DNA-labeled carbon dots (DNA-CDs) and 5,7-dinitro-2-sulfo-acridone (DSA) coupling with the target-catalyzing signal amplification for the detection of exosomal miRNA-21. There was high fluorescence resonance energy transfer (FRET) efficiency between carbon dots (CDs) and DSA when the bioprobe was assembled. However, in the presence of the target, with disassembling of the fluorescent bioprobe, the fluorescence intensities of CDs and DSA were changed simultaneously. Because of the ratio of dual fluorescence intensities, this ratiometric fluorescent bioprobe was able to cancel out environmental fluctuations by calculating emission intensity ratio at two different wavelengths, being robust and stable enough for detection of exosomal miRNA-21. In addition, we displayed that a single miRNA-21 can catalyze the disassembly of multiple CDs with DSA theoretically, yielding significant change in the fluorescence ratio for the detection of miRNA-21. With this signal amplification strategy, the limit of detection was as low as 3.0 fM. Furthermore, because of the introduction of lock nucleic acid to mediate the strand displacement reaction, the selectivity of this strategy was improved remarkably, even against single base mismatch sequence. More importantly, our strategy could monitor the dynamic change of exosomal miRNA-21, which maybe becomes a potential tool to distinguish cancer exosomes and nontumorigenic exosomes. In a short, this ratiometric fluorescence bioprobe possessed high stability, sensitivity and selectivity coupling with ease of operation and cost efficiency, leading to great potential for wide application