Augmented reality (AR) is a field of technology that has evolved drastically during the last decades, due to its vast range of applications in everyday life. The aim of this paper is to provide researchers with an overview of what has been surveyed since 2010 in terms of AR application areas as well as in terms of its technical aspects, and to discuss the extent to which both application areas and technical aspects have been covered, as well as to examine whether one can extract useful evidence of what aspects have not been covered adequately and whether it is possible to define common taxonomy criteria for performing AR reviews in the future. To this end, a search with inclusion and exclusion criteria has been performed in the Scopus database, producing a representative set of 47 reviews, covering the years from 2010 onwards. A proper taxonomy of the results is introduced, and the findings reveal, among others, the lack of AR application reviews covering all suggested criteria.

The microstructure and mechanical properties of ethanol-denatured, acid-induced whey protein (WPI) cold-set gels have been monitored by confocal laser scanning microscopy and rheology. As the ethanol concentration increased, the porosity of the gels progressively decreased, with gels prepared at ethanol concentrations of 50 and 70 g/100 g lacking microscopically visible pores. Large aggregates were observed at ethanol concentrations of 70 g/100 g immediately after alcohol addition. A sharp increase in storage modulus was noted at ethanol concentrations between 30 and 50 g/100 g, while the gel strength at 50 g/100 g, was up to three times higher compared to that of heat-denatured gels. In general, the ethanol-denatured whey protein cold-set gels were prone to phase separation. Ethanol-denatured cold-set whey protein gels exhibited mechanical and microstructural properties that may offer alternative means of structuring protein-enriched food formulations and designing novel food products.

Top-down cracking (TDC) is a deterioration mechanism where cracks initiate at the pavement surface and propagate downwards with time. It is caused by horizontal tensile strains generated at the tire-pavement contact area. This paper presents a methodology for determining the thickness of the asphalt layer above which TDC will be the predominant deterioration mechanism in comparison to the bottom up cracking. The methodology covers two scenarios: one when all asphalt layers have the same stiffness modulus and the other when the asphalt layers have two different stiffness moduli. i.e. stiffness of surface layer (40 mm thick), S1, and stiffness of the rest of asphalt layers, S2. The findings concluded that in flexible and semi-flexible pavements with uniform asphalt stiffness layers, when the thickness of the asphalt layers is above a value within the range 100–210 mm (for ESAL80 axle loading), the pavement will most probably fail due to top-down cracking and not due to bottom up cracking. The exact thickness above which TDC will occur depends on the magnitude of Foundation Surface Modulus (FSM) and the asphalt stiffness. Similar range of thicknesses was found (100–230 mm) above which TDC will occur in flexible pavements with non-uniform asphalt stiffness values (S1/S2 is up to 1.13). A case study along a motorway section of 16 km long confirms the findings of the methodology developed.

Human embryos evaluation is one of the most important challenges in vitro fertilization (IVF) programs. The morphokinetic and the morphology parameters of the early cleaving embryo are of critical clinical importance. This stage spans the first 48 h post-fertilization, in which the embryo is dividing in smaller blastomeres at specific time-points. The morphology, in combination with the symmetry of the blastomeres, seem to be powerful features with strong prognostic value for embryo evaluation. To date, the identification of these features is based on human inspection in timed intervals, at best using camera systems that simply work as surveillance systems without any precise alerting and decision support mechanisms. This paper aims to develop a computer vision technique to automatically detect and identify the most suitable cleaving embryos (preferably at Day 2 post-fertilization) for embryo transfer (ET) during treatments. To this end, texture and geometrical features were used to localize and analyze the whole cleaving embryo in 2D grayscale images captured during in-vitro embryo formation. Because of the ellipsoidal nature of blastomeres, the contour of each blastomere is modeled with an optimal fitting ellipse and the mean eccentricity of all ellipses is computed. The mean eccentricity in combination with the number of blastomeres form the feature space on which the final criterion for the embryo evaluation is based. Experimental results with low quality 2D grayscale images demonstrated the effectiveness of the proposed technique and provided evidence of a novel automated approach for predicting embryo quality.

The functional properties of whey proteins after exposure to ethanol were studied. The reversibility of the ethanol-induced whey protein denaturation was investigated using different methodologies to remove ethanol, such as 10-fold dilution with water, oven-drying and freeze-drying of whey protein mixed water/ethanol solutions. The effect of ethanol on whey protein denaturation, before and after ethanol removal, was measured by analysis of difference-UV spectra, rheological measurements, confocal microscopy and differential scanning calorimetry. The results showed a retention of the denatured character of whey proteins (27-34%) after removal of ethanol. The study of the combined effect of ethanol and heat on whey protein denaturation at concentrations ranging from 10 to 70%, revealed that at an ethanol concentration of 50%, the initial extent of denaturation was maximum, while heat did not contribute any additional denaturation effect. A whey protein mixture, previously incubated in 50% ethanol and subsequently freeze-dried to completely remove ethanol, produced a gel in a cold-set gelation procedure, where gelation was promoted by addition of glucono-delta-lactone, without an initial heating step. The confocal microscope revealed significant microstructural characteristics suggesting that whey protein solutions retain a significant degree of denaturation even after ethanol removal. Differential scanning calorimetry results further showed that the presence of 50% ethanol decreased the denaturation temperature of whey proteins by more than 15 degrees C, while removal of ethanol by freeze-drying, similarly decreased the denaturation temperature by about 2 degrees C. Overall, whey proteins, exposed in ethanol, retain a significant degree of denaturation after removal of the alcohol, with possible applications as functional ingredients capable of modifying the mechanical properties of food systems.

A newly developed method of analysis of difference-UV spectra was successfully implemented in the study of the effect of heat, pH, ultrasonication and ethanol on the denaturation of whey protein isolate. It was found that whey proteins exhibit their highest stability against heat denaturation at pH 3.75. At very low pH values, i.e. 2.5, they exhibited considerable cold denaturation, while after heating at this pH value, the supplementary heat denaturation rate was lower compared to that at neutral pH. The highest heat denaturation rates were observed at pH values higher than neutral. High power sonication on whey proteins, previously heated at 90 degrees C for 30 min, resulted in a rather small reduction of the fraction of the heat denatured protein aggregates. Finally, when ethanol was used as a cosolvent in the concentration range 20-50%, a sharp increase in the degree of denaturation, compared to the native protein solution, was observed. (C) 2017 Elsevier Ltd. All rights reserved.

A novel approach in the analysis of difference-UV spectrophotometric data for determining the heat denaturation degree of bovine serum albumin (BSA) was assessed. Five different parameters of difference-UV spectra were obtained by subtracting spectra of unheated and denatured protein solutions at different temperature-time combinations. BSA was found to exhibit a maximum degree of heat denaturation of about 17% compared to the complete unfolding caused by 6 M guanidine hydrochloride. This low degree of heat denaturation is probably caused by the aggregation of the initially unfolded protein molecules. The kinetic analysis exhibited discontinuities in the Arrhenius plots, distinguishing the unfolding and aggregation phases of the denaturation process, whereas such a discrimination could not be obtained by differential scanning calorimetry analyses. The proposed method is accurate, fast, simple and sensitive enough to detect changes in the protein heat denaturation even at short temperature-time intervals.

The current paper describes a new technique for embedding secret data in JPEG compressed color digital images. Emphasis is given in improving effective payload percentage over file size increase while retaining low distortion levels. The proposed technique is based on modification of non-zero quantized coefficients. In contrast to previously proposed techniques, the present one does not require the use of non-standard Huffman tables. Apart from that, no side information needs to be included in a JPEG header to assist the decoder in extracting the hidden message. The main idea behind the technique is to create zero population bins in the coefficient histogram in order to accommodate the secret message bits. Specifically, all coefficients whose absolute value is L are modified by 1 in the direction of their sign when a bit 1 is to be embedded or are not modified when a bit 0 is to be embedded. Coefficients with absolute values greater than L are also incremented by one in the direction of their sign, so that they are not confused with coefficients where embedding has occurred. At the side of the decoder, both the message bits can be extracted from coefficients with absolute values L and L+1, and the original image can be restored by shifting all coefficients with absolute value greater than L in the opposite direction of their sign. The results show significant improvement in comparison with representative state-of-the-art techniques, in terms of ratio of payload over file size increase.

A novel technique for data hiding in JPEG images is proposed. The technique relies on modification of zero quantised coefficients in each image block, in contrast to most previously proposed methods which also affect non-zero coefficients and/or the quantisation tables. Both embedding and extraction are performed on a per-block basis, without the need to preprocess the whole image. The proposed technique provides significantly lower distortion for similar embedding capacity, compared with recent state-of-the-art techniques.

List of contributions from the CTA Consortium presented at the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands.

The Cherenkov Telescope Array (CTA) is a new observatory for very high-energy (VHE) gamma rays. CTA has ambitions science goals, for which it is necessary to achieve full-sky coverage, to improve the sensitivity by about an order of magnitude, to span about four decades of energy, from a few tens of GeV to above 100TeV with enhanced angular and energy resolutions over existing VHE gamma-ray observatories. An international collaboration has formed with more than 1000 members from 27 countries in Europe, Asia, Africa and North and South America. In 2010 the CTA Consortium completed a Design Study and started a three-year Preparatory Phase which leads to production readiness of CTA in 2014. In this paper we introduce the science goals and the concept of CTA, and provide an overview of the project.

The clinical success of large class II resin-modified glass-ionomer cement/composite resin (RMGIC/CR) ‘open-sandwich’ restorations in permanent or primary molars may be influenced by certain bonding parameters.

Abstract: The paper statistically analyzes the behaviour of chaotic watermarksignals generated by n-way Bernoulli shift maps.For this purpose, a simple blind copyright protection watermarkingsystem is considered. The analysis involves theoreticalevaluation of the system detection reliability, whena correlator detector is used. The system is modeled in acommunication framework considering the signal as interferenceand converting the addressed problem to the detectionof the underlying watermark...

The current paper introduces a novel method for inserting data in a grayscale image without the need to include any overhead information in order to pinpoint the embedding positions or any other alteration of gray values. The method is semi-reversible in the sense that the hidden data are correctly extracted, whereas the original image is not necessarily restored. This is a realistic scenario for steganography purposes, where the important information is the hidded data and not the cover image. The method involves calculation of image block histograms. Based on the form of its histogram, a block is either selected or not for data hiding. The method is tested with many commonly used images and compared to a state of the art technique. Its performance is superior, in terms of capacity, to this method for quite similar distortion levels.

Compilation of CTA contributions to the proceedings of the 33rd International Cosmic Ray Conference (ICRC2013), which took place in 2-9 July, 2013, in Rio de Janeiro, Brazil

The purpose of this article is to present a novel method for region based image watermarking that can tolerate local image distortions to a substantially greater extent than existing methods. The first stage of the method relies on computing a normalized version of the original image using image moments. The next step is to extract a set of feature points that will act as centers of the watermark embedding areas. Four different existing feature extraction techniques are tested: Radial Symmetry Transform (RST), scale-invariant feature transform (SIFT), speeded up robust features (SURF) and features from accelerated segment test (FAST). Instead of embedding the watermark in the DCT domain of the normalized image, we follow the equivalent procedure of first performing the inverse DCT of the original watermark, inversely normalizing it and finally embedding it in the original image. This is done in order to minimize image distortion imposed by inversely normalizing the normalized image to obtain the original. The detection process consists of normalizing the input image and extracting the feature points of the normalized image, after which a correlation detector is employed to detect the possibly inserted watermark in the normalized image. Experimental results demonstrate the relative performance of the four different feature extraction techniques under both geometrical and signal processing operations, as well as the overall superiority of the method against two state-of-the-art techniques that are quite robust as far as local image distortions are concerned.

A novel technique for image watermarking aiming at robustness against geometrical attacks is proposed in the current paper. The first stage relies on computing a normalized version of the original image using image moments. A radial symmetry transform is then applied to the normalized image, followed by a non-maxima suppression step. The feature points extracted this way act as centers of the area where the watermark is to be embedded. To minimize image distortion, we embed the inversely normalized watermark (initially formed in the DCT domain) in the original image. The detection process consists of normalizing the input image, applying the radial symmetry transform and extracting the feature points, after which a correlation detector is employed to detect the possibly inserted watermark in the normalized image. Experimental results prove the robustness of the method against affine geometrical transform attacks, as well as other image processing operations.

In this paper a benchmarking system for watermarking algorithms is described. The proposed benchmarking system can be used to evaluate the performance of watermarking methods used for copyright protection, authentication, fingerprinting, etc. Although the system described in the paper is used for image watermarking, the general framework can be used, by introducing a different set of attacks, for benchmarking of video and audio data.

A crucial preprocessing stage in applications such as OCR is text extraction from mixed-type documents. The present work, in contrast to most until now, successfully faces the problem of varying text orientation and size. The technique first identifies marks using a contour following technique, followed by a PCA (principal component analyzer) which determines the direction of the main axis of each mark. Next, a nearest-neighbor technique is employed to find the shortest distances between marks, and a feature vector is formed based on calculated mark dimensions and distances, which is then fed into a SOFM (self organizing feature map) which defines homogeneous mark clusters. Resulting cluster weights and variances are used to form a set of fuzzy rules, and a fuzzy classification scheme identifies marks as characters or non-characters. The technique succeeds in correctly and quickly extracting text areas in a variety of mixed-type documents.

Text extraction from documents is an essential preprocessing stage of applications such as OCR (optical character recognition), document image compression, storage and retrieval. Although many different techniques have been proposed to date, they usually assume that text orientation and size is fixed throughout the document image. Our work faces the problem of varying orientation and size, which is often the case in practice, either because of the nature of the original document or due to imposed distortions. Our algorithm first identifies marks using a suitable contour following technique. A PCA (principal component analyzer) is afterwards employed in order to determine the principal axes of each mark, and a nearest-neighbor technique is used to find the shortest distances between marks. A feature vector is formed based on mark dimensions and distances between them, which is then fed into a SOFM (self-organizing feature map) in order to divide the marks into homogeneous clusters. A set of fuzzy rules is formed using all cluster weights and variances. Finally, a fuzzy classification scheme identifies each mark as a character or a non-character. The technique was tested on a variety of mixed-type documents and it proved to be quite fast and accurate.