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Abstract Arsenic poisoning of water resources has been of universal concern because of its serious health impact and on the ecosystem. As such, several efforts have been made on promising optical detection of arsenic utilizing various transduction platforms. However, the substantial role of sensor material cannot be ignored in the design of cost-effective, environment-friendly, and user acceptable sensor systems for on-site/in-field application. The goal is to employ sensor materials that enable detection of arsenic with high sensitivity, selectivity, reproducibility, and stability. In the present review, we have covered and critically deliberated upon the progress made over 2013–2018 in sensor materials, including colorimetric dyes, organic fluorophores, nanostructures (metal, carbon, semiconductor, metal oxides, etc.), and bioreceptors (aptamers, peptides, whole cells, etc.), for optical detection of arsenic in water. The possible integration of microfluidics/paper fluidics and imaging with existing optical sensor materials to realize a user friendly system for varied settings is also discussed. Graphical abstract Image 1 Highlights • Aquatic arsenic pollution: A global problem. • Optical chemo sensors for arsenic detection in water. • Nano materials in arsenic optical detection. • Environment friendly carbon nanostructures as emerging sensor probes. • Role of paper analytical devices and Imaging techniques in arsenic quantification. [ABSTRACT FROM AUTHOR]

Although obesity is typically defined by body mass index criteria, this does not differentiate true body fatness, as this includes both body fat and muscle. Therefore, other fat depots may better define cardiometabolic and cardiovascular disease (CVD) risk imposed by obesity. Data from translational, epidemiological, and clinical studies over the past 3 decades have clearly demonstrated that accumulation of adiposity in the abdominal viscera and within tissue depots lacking physiological adipose tissue storage capacity (termed "ectopic fat") is strongly associated with the development of a clinical syndrome characterized by atherogenic dyslipidemia, hyperinsulinemia/glucose intolerance/type 2 diabetes mellitus, hypertension, atherosclerosis, and abnormal cardiac remodeling and heart failure. This state-of-the-art paper discusses the impact of various body fat depots on cardiometabolic parameters and CVD risk. Specifically, it reviews novel and emerging imaging techniques to evaluate adiposity and the risk of cardiometabolic diseases and CVD. • Anthropometric and laboratory markers of obesity have limited utility for personalized treatment. Direct imaging measures of obesity may improve diagnosis, guide decision-making for appropriate interventions, and monitor responses to treatment. • Multimodality imaging is used to assess visceral and ectopic fat depots (such as within the heart, liver, skeletal muscle, pancreas, and kidney) to improve evaluation of metabolic disease and CVD risk. • Future studies will combine body fat assessment with physical activity/cardiorespiratory fitness to further improve efforts to prevent and treat obesity and its progression to CVD. [ABSTRACT FROM AUTHOR]

Cheese is produced around the world in a wide range of flavours, varieties, textures, and shapes, which can be used as a final product in human diet, and as an important ingredient in various foods. With consumer's continuing demand for quality cheese as well as increasing challenge from production facing the industry, nondestructive techniques are increasingly used to evaluate cheese quality. Considering the rapid development of novel nondestructive techniques, relevant literatures in the past 15 years (2004–2018) are reviewed in this paper. The main quality attributes of cheese and the importance of evaluating these attributes are discussed. The principles, developments and applications of computer vision (CV), computed tomography (CT), X-ray system, magnetic resonance imaging (MRI), fluorescence spectroscopy, near-infrared (NIR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, hyperspectral imaging (HSI), Raman imaging, ultrasonic and acoustic sensing and other nondestructive techniques are discussed in this review. Among all nondestructive techniques used for cheese quality evaluation, fluorescence spectroscopy is the most used method for classification, NIR spectroscopy is mainly used for predicting chemical components, FTIR spectroscopy shows the greatest scope of applications, while CV, X-ray and MRI are only used for monitoring eye growth. HSI and Raman imaging begins to attract research interest, and synchronous fluorescence spectroscopy gradually replaces front-face fluorescence spectroscopy, whereas CV is no longer applied to cheese evaluation and literatures about NIR spectroscopy also becomes less in recent years. It is hoped that this review should provide information on current research gaps and set some directions for future studies. • Nondestructive techniques for cheese quality evaluation are reviewed. • Cheese attributes and their importance are presented. • Applicability and the pros and cons of nondestructive techniques are discussed. • Future research directions are suggested. [ABSTRACT FROM AUTHOR]

High definition (HD) video cameras have been used to record daily activities at construction jobsites into videos. These videos contain rich workforce and equipment information for site engineers and project managers to analyze construction productivity, monitor construction progress, inspect jobsite safety, etc. However, it is difficult to automatically retrieve such information from the videos, since existing methods for the detection of construction workforce and equipment could not reach high precision and recall at the same time. This paper presents a novel framework that integrates the visual tracking into the detection of construction workforce and equipment. The integration significantly improves the recall and meanwhile maintains high precision. The proposed framework has been tested in real construction jobsites. Although it does not process the jobsite videos in real time yet, the test results showed that the recall for the detection of construction workforce and equipment was improved by more than 30–50%, while maintain the precision at the same level. [ABSTRACT FROM AUTHOR]

This paper demonstrates that an educated methodology based on both non-invasive and micro invasive techniques in a two-step approach is a powerful tool to characterize the materials and stratigraphies of an Egyptian coffin, which was restored several times. This coffin, belonging to a certain Mesiset, is now located at the Museo Civico Archeologico of Bologna (inventory number MCABo EG 1963). Scholars attributed it to the late 22nd/early 25th dynasty by stylistic comparison. The first step of the diagnostic approach applied imaging techniques on the whole surface in order to select measurements spots and to unveil both original and restored areas. Images and close microscopic examination of the polychrome surface allowed selecting representative areas to be investigated in situ by portable spectroscopic techniques: X-ray Fluorescence (XRF), Fiber Optic Reflectance Spectroscopy (FORS) and Fourier Transform Infrared spectroscopy (FTIR). After the analysis of the results coming from the first step, very few selected samples were taken to clarify the stratigraphy of the polychrome layers. The first step, based on the combination of imaging and spectroscopic techniques in a totally non-invasive modality, is quite unique in the literature on Egyptian coffins and enabled us to reveal many differences in the ground layer’s composition and to identify a remarkable number of pigments in the original and restored areas. This work offered also a chance to check the limitations of the non-invasive approach applied on a complex case, namely the right localization of different materials in the stratigraphy and the identification of binding media. Indeed, to dissolve any remaining doubts on superimposed layers belonging to different interventions, it was necessary to sample few micro-fragments in some selected areas and analyze them prepared as cross-sections. The original ground layer is made of calcite, while the restored areas show the presence of either a mixture of calcite and silicates or a gypsum ground, overlapped by lead white. The original pigments were identified as orpiment, cinnabar and red clay, Egyptian blue and green copper based pigments. Some other pigments, such as white lead, Naples yellow, cerulean blue and azurite were only found in the restored areas. [ABSTRACT FROM AUTHOR]

Abstract: From numerical point of view, analysis and optimization in computational material engineering require efficient approaches for microstructure representation. This paper develops an approach to establish an image-based interpolation model in order to efficiently parameterize microstructures of a representative volume element (RVE), based on proper orthogonal decomposition (POD) reduction of density maps (snapshots). When the parameters of the RVE snapshot are known a priori, the geometry and topology of individual phases of a parameterized snapshot is given by a series of response surfaces of the projection coefficients in terms of these parameters. Otherwise, a set of pseudo parameters corresponding to the detected dimensionality of the data set are taken from learning the manifolds of the projection coefficients. We showcase the approach and its potential applications by considering a set of two-phase composite snapshots. The choice of the number of retained modes is made after considering both the image reconstruction errors as well as the convergence of the effective material constitutive behavior obtained by numerical homogenization. [Copyright &y& Elsevier]

Abstract: Hydrodynamics play an important role in the structure of many marine ecosystems of bivalves. After severe storm periods, large amounts of the Cerastoderma edule stocks were transported from the Lombos do Ulla shellfish bed (Spain). This paper presents the results of laboratory experiments carried out to analyze the bedload transport of this bivalve emulating the stormy shellfish bed conditions. Flow velocities were measured using particle image velocimetry and the double averaged methodology was applied to determine the main flow characteristics over different cockle patches. The flow structure exhibits properties of skimming and isolated flows depending on the density of bivalves. Bed shear stress was determined from the log-law and the cockles were geometrically characterized in order to derive specific bedload transport equations in a conventional deterministic sediment transport framework. The obtained formulas can be implemented in common numerical codes to further analyze mollusk stability, bedload transport and dispersal in their aquatic systems. [Copyright &y& Elsevier]

Abstract: The measurement of strain has always been central to developments in structural engineering. As structures around the world reach the end of their intended service life, there is a need for more robust field monitoring techniques to determine, in conjunction with numerical models, if these structures are still fit for purpose. Current strain gage technologies are only able to offer a limited number of discrete measurements, which often is not enough data to assess complex structures. This paper presents an alternative technique for measuring strain using digital images called Digital Image Correlation (DIC) that allows for the measurement of 2-D strain fields. The accuracy that can be achieved in physical experiments where sources of error such as lighting and camera quality are present is investigated. A series of tension tests on steel plates are conducted allowing measurements from the DIC technique to be compared to measurements from conventional foil strain gages. Out-of-plane motion is identified as one of the most significant potential sources of strain measurement error when using DIC. Five solutions for significantly reducing the effects of out-of-plane motion are presented and three of these solutions are applied to the steel plate experiment. Using these solutions it is possible to achieve mean strain errors of less than 5με when comparing DIC to foil strain gage measurements, which suggests that the DIC technique has the potential to replace conventional strain gages. Areas of future research are also introduced. [Copyright &y& Elsevier]

Abstract: With the capability of capturing detailed geometry of bridges in minutes, laser scanning technology has attracted the interests of bridge inspectors and researchers in the domain of bridge management. A challenge of effectively utilizing laser scanned point clouds for bridge inspection is that inspectors need to manually extract and measure large numbers of geometric features (e.g., points) for deriving geometric information items (e.g., the minimum underclearance) of bridges, named as bridge surveying goals in this research. Tedious manual data processing impedes inspectors from quantitatively understanding how various data processing options (e.g., algorithms, parameter values) influence the data processing time and the reliabilities of the surveying goal results. This paper shows the needs of automatic workflow executions for extracting surveying goals from laser scanned point clouds, and presents a computational framework for addressing these needs. This computational framework is composed of formal representations of workflows and mechanisms for constructing and executing workflows. Using a prototype system implemented based on this framework, we constructed and quantitatively characterized three workflows for extracting three representative bridge surveying goals, using three metrics of workflow performance defined in this research: exhaustiveness of measurement sampling, reliability of surveying goal results, and time efficiency. [Copyright &y& Elsevier]

Abstract: Tracking of project related entities such as construction equipment, materials, and personnel is used to calculate productivity, detect travel path conflicts, enhance the safety on the site, and monitor the project. Radio frequency tracking technologies (Wi-Fi, RFID, UWB) and GPS are commonly used for this purpose. However, on large-scale sites, deploying, maintaining and removing such systems can be costly and time-consuming. In addition, privacy issues with personnel tracking often limits the usability of these technologies on construction sites. This paper presents a vision based tracking framework that holds promise to address these limitations. The framework uses videos from a set of two or more static cameras placed on construction sites. In each camera view, the framework identifies and tracks construction entities providing 2D image coordinates across frames. Combining the 2D coordinates based on the installed camera system (the distance between the cameras and the view angles of them), 3D coordinates are calculated at each frame. The results of each step are presented to illustrate the feasibility of the framework. [Copyright &y& Elsevier]

Abstract: The understanding of deposition of particles in the respiratory tract is of great value to risk assessment of inhalation toxicology and to improve efficiency in drug delivery of inhalation therapies. There are three main basic mechanisms of particle deposition based primarily on particle size: inertial impaction, sedimentation and diffusion. The regional deposition in the lungs can be evaluated in regards to the aerodynamic particle size, in which particle density plays a significant role. In this review paper, we first introduce the available imaging techniques to confirm regional deposition of particles in the human respiratory tract, such as planar scintigraphy, single photon emission computed tomography (SPECT) and positron emission tomography (PET). These technologies have widely advanced and consequently benefited the understanding of deposition pattern, although there is a lack of lung dosimetry techniques to evaluate the deposition of nanoparticles. Subsequently, we present a comprehensive review summarizing the evidence available in the literature that confirms the deposition of smaller particles in the smaller airways as opposed to the larger airways. [Copyright &y& Elsevier]

Abstract: Diseases in plants cause major production and economic losses in agricultural industry worldwide. Monitoring of health and detection of diseases in plants and trees is critical for sustainable agriculture. To the best of our knowledge, there is no sensor commercially available for real-time assessment of health conditions in trees. Currently, scouting is most widely used mechanism for monitoring stress in trees, which is an expensive, labor-intensive, and time-consuming process. Molecular techniques such as polymerase chain reaction are used for the identification of plant diseases that require detailed sampling and processing procedure. Early information on crop health and disease detection can facilitate the control of diseases through proper management strategies such as vector control through pesticide applications, fungicide applications, and disease-specific chemical applications; and can improve productivity. The present review recognizes the need for developing a rapid, cost-effective, and reliable health-monitoring sensor that would facilitate advancements in agriculture. It describes the currently used technologies that can be used for developing a ground-based sensor system to assist in monitoring health and diseases in plants under field conditions. These technologies include spectroscopic and imaging-based, and volatile profiling-based plant disease detection methods. The paper compares the benefits and limitations of these potential methods. [Copyright &y& Elsevier]

Abstract: In estuaries dominated by cohesive sediments, tidal variation in the size distribution of suspended particulates has important implications for automated suspended sediment monitoring, since instrument calibration must typically take account of both sediment concentration and particle size. Particle size variation at tidal time-scales also directly affects the parameterisation of numerical sediment transport models through its effect on the settling velocity. In situ measurements of particle size are preferred, since the behaviour of complex particle aggregates (flocs) is strongly influenced by turbulence intensity. A variety of in situ particle size measurements systems have been developed, mostly based upon either direct photographic or video imaging, or the analysis of optical or acoustic scattering. However, existing systems are expensive and/or unsuited to small-boat deployment. This paper describes a new low-cost particle sizing system that can easily be deployed within shallow estuarine and coastal waters. The In situ Particle Imaging Device (InSiPID) combines twin CCD video cameras with fully automated digital image acquisition and processing algorithms for the extraction of size and shape statistics. The system has a useful imaging range of approximately 4 to 3000 μm. It has been tested in concentrations in the range 5 to 400 mg l−1, and provides near real-time analysis of image ensembles using a compact portable computer. The image processing algorithms are specifically designed for the analysis of flocculated particles, and perform well against manual analysis of laboratory standards. A trial deployment within a small UK estuary reveals a clear bimodality in particle size, with the proportion of suspended material contained within these distinct micro- and macro-floc modes varying both within and between spring and neap tides. InSiPID is considerably cheaper than alternative systems. It is also more flexible in that additional functionality can be implemented in software without any major alteration to the underlying hardware. [Copyright &y& Elsevier]

This paper provides an overview of three different image acquisition approaches for automatic visual inspection of metallic surfaces. The first method is concerned with gray-level intensity imaging, whereby the most commonly employed lighting techniques are surveyed. Subsequently, two range imaging techniques are introduced which may succeed in contrast to intensity imaging if the reflection property across the intact surface changes. However, range imaging for surface inspection is restricted to surface defects with three-dimensional characteristics, e.g. cavities. One range imaging approach is based on light sectioning in conjunction with fast imaging sensors. The second introduced range imaging technique is photometric stereo. [Copyright &y& Elsevier]

• An automated visual system for recognizing tunnel cracks is proposed. • Prior noise judgment achieves differentiated noise filtering. • The system combines adaptive partitioning, double threshold and edge detection. Structural health monitoring (SHM) combined with digital image technology has been widely applied to infrastructure operation management. However, the linear illumination of the tunnel and the various lining diseases limit the quality of lining-crack recognition. In this article, a novel tunnel-lining crack recognition system is established. The system involves three main procedures: image preprocessing and enhancement, feature extraction, and crack characterization. To meet tunnel environmental conditions, mature image enhancement and morphological algorithms are packaged into the system; meanwhile, this paper proposes differentiated noise filtering and an improved segmenting method combining adaptive partitioning, edge detection and threshold method to improve the recognition accuracy. A self-regulating calibration method that uses parallel projection is also applied to crack characterization, achieving real-time size calibration. The results of experiments to compare the effects of the proposed system and field application tests confirm the stability and reliability of the system. A further deviation factor analysis provides reasonable suggestions for system improvement. [ABSTRACT FROM AUTHOR]