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Aim To compare the degree of fibre shedding by six brands of endodontic paper point when used for the paper point technique ( PPT) of working length confirmation. Methodology An in vitro model simulating the clinical use of paper points in PPT was used to assess the degree of fibre shedding of six brands of size 20, .02 taper paper point. Whilst observing the artificial terminal foramen with polarized light microscopy, the number of fibres shed directly (point inserted 1 mm beyond the terminal foramen) and indirectly (point inserted to length then a gutta-percha point inserted) was assessed. The degree of direct fibre shedding as a function of brand was analysed with Fisher's exact test and multiple pairwise comparisons. Indirect fibre shedding was analysed with Kruskal-Wallis and Wilcoxon rank-sum tests. Results All brands shed fibres both directly and indirectly, with a significant influence of brand on the proportion of fibres shed directly ( P < 0.0306) and on the mean number of fibres shed indirectly ( P < 0.0001). Post hoc analysis demonstrated a similar hierarchy of point integrity for both tests with Classic (UnoDent, Witham, UK) shedding significantly more than other brands and SS White (Gloucester, UK) and Antæos® ( VDW, Munich, Germany) shedding the least. Conclusion All brands of paper point may shed cellulose fibres both directly and indirectly with a significant influence of brand on the degree of fibre shedding. Further work should be undertaken to develop biocompatible absorbent dental points. [ABSTRACT FROM AUTHOR]

Slug flow processes draw much attention in chemical and pharmaceutical manufacturing thanks to their ability to eliminate downtime costs and batch‐to‐batch variation. Using in‐line video can monitor the current process status and improve the stability of the slug flow. However, there are no effective image processing methods aiming at such videos from chemical experiments due to limited training sample size and the variety of experimental settings. The paper proposes a training‐free method to automatically detect and measure the slugs from in‐line videos. Multiple image features are fused to identify the slug shapes under various lighting conditions, a six‐point model is fitted to achieve better volume estimation, and a consistency score is estimated to quantify the detection uncertainty. The proposed algorithm achieves similar results to manual labeling for various types of slug flow processes, improving the accuracy of slug column estimation by a large margin compared to the existing automatic methods. Finally, using it to monitor the slug flow process's stability and the change of the slug volume in an injection point are demonstrated. The method not only shows that handcrafted image features have the capability for detection and segmentation from chemical experiment images but also paves the road for a training‐based algorithm for the task. [ABSTRACT FROM AUTHOR]

This paper presents a novel technique to evaluate OSNR using asynchronous histograms. The technique is based on a comparison between a numerically estimated asynchronous histogram of the signal to be measured and the monitored signal. Experimental validation of proposed technique is presented. Measurement errors below 1 dB are achieved for OSNR values below 32 dB. The proposed technique is also validated for cases where the monitored signal presents significant dispersion-induced distortion, without presenting significant loss of accuracy. The principal limitations of the proposed technique are also investigated. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1369–1372, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21648 [ABSTRACT FROM AUTHOR]

In this investigation, three subjects are considered. First, the effect of the human factor is examined. In carrying out analyses of fatigue delamination propagation tests on laminate composites, the delamination length must be measured. The human effect on measurement of the delamination length a by different investigators is discussed. A limited influence of the human factor on the measurement of the delamination length a, as well as on delamination propagation rate da/dN, is observed in this study. Secondly, the paper proceeds to discuss the influence of the R‐ratio on the fatigue delamination growth rate. It is found that a higher rate of crack/delamination propagation is associated with lower R‐ratios which appears to contradict conventional wisdom. This behavior is confirmed in tests. Thirdly, a comparison between the fatigue propagation rates of two material systems is considered. It is concluded that the energy release rate used to assess these materials should not be normalized. Highlights: Impact of human factor on fatigue delamination tests in laminate composites.Limited influence of the human factor on delamination length and propagation rate.The lower the R‐ratio, the higher the delamination propagation rate.The crack driving force for laminates should be taken as GImax. [ABSTRACT FROM AUTHOR]

Accurate fish size measurement in breeding areas is crucial for the fishing industry. Unlike acoustic methods with high equipment cost and low measurement accuracy, current image‐based methods offer a promising alternative. However, these image‐based methods still face challenges in selecting measurement points. To address this issue and achieve precise measurements of individual fish, this paper introduces an automatic fish size measurement method based on key point detection. We established a Fish‐Keypoints dataset and utilized deep learning techniques for the detection of fish and their key points. Using a binocular camera system, we reconstruct a three‐dimensional coordinate system to measure key points at the fish's head and tail, facilitating fish length calculation. The detection model achieves an accuracy of 85.1% in key point detection. The proposed method is tested in both land and underwater environments, demonstrating a relative measurement error of approximately 7% for fish in pools. This confirms the proposed method's ability to accurately detect measurement points, offering superior accuracy compared to other methods. [ABSTRACT FROM AUTHOR]

Phase retrieval gives the problem of recovering some signal from phaseless measurements. This paper mainly studies the stability estimation of phase recovery from the measurement of discrete linear canonical Gabor transformation (DLCGT). We first show that we can recover the signal x$$ x $$ on the connected components of G$$ G $$ in global phase sense. Then, we give the stability estimates results from the DLCGT measurements and the autocorrelation relation. [ABSTRACT FROM AUTHOR]

Reactive flash sintering is a process where off‐the‐shelf powders of elemental oxides can be simultaneously sintered and reacted to form a multicomponent oxide in a matter of seconds at low furnace temperatures. The fact that several cation species, each residing within their own particles, can migrate over distances of several micrometers, and mix on the atomic scale to form multicomponent oxides, so quickly, is quite remarkable. The question arises as to the rate of this solid‐state diffusion phenomenon. In this paper, we present measurements of this diffusion coefficient from live flash experiments. The results are obtained from millimeter scale bilayers of yttria‐stabilized zirconia and lanthana where the flash initiates in the zirconia layer and then migrates into the lanthana layer, forming lanthanum zirconates. The velocities of migration of the flash‐front, coupled with measurements of the length scale of the profile of zirconium and lanthanum interdiffusion, across the bilayer interface, provide an estimate of the effective diffusion coefficient. These measurements give a value for the cation diffusion to lie in the range of 2.5 × 10−10 m2 s−1 at 1380°C, with an activation energy of 200–250 kJ mol−1. In comparison, the cation diffusion coefficient in yttria‐stabilized zirconia, at 1350°C, is stated to be 1.1 × 10−20 m2 s−1 with an activation energy of ∼550 kJ mol−1. A pause for reflection. [ABSTRACT FROM AUTHOR]

This paper presents the development of a metamaterial‐based microwave sensor for dielectric constant measurements. The sensor is constructed with a circular split‐ring resonator on one side and a coplanar waveguide transmission line on the other side. The proposed sensor has a size of 35 mm × 35 mm × 1.27 mm and resonates at 3.31 GHz. The sensor is fabricated on a RO3210 substrate with a dielectric constant of 10.2 and a loss tangent of 0.003. Both the simulation and experimental measurements show a linear relationship between the shift of the resonance frequency and the dielectric constants of the test samples, with a coefficient of determination R2 above 0.99. The dielectric constant of an unknown material can therefore be easily estimated using the inverse linear regression model. To validate the performance of the sensor, three known substrate materials, namely, Rogers RT6002, FR4, and Rogers TMM10, were used as test samples. The measured dielectric constants for these three materials were 2.8045, 4.3775, and 8.8719, respectively. The results agree closely with those indicated in the data sheets, with discrepancies of less than 5%. [ABSTRACT FROM AUTHOR]

Determining which bilateral bones belong to the same person based on shape and size similarity is called pair‐matching and it is instrumental for sorting commingled skeletons. To date, pair‐matching has popularly been accomplished by visual inspection and/or linear caliper measurements; however, attention is turning increasingly to computational analysis. In this paper, we investigate a fast three‐dimensional (3D) computerized shape‐analysis method for whole‐bone pair‐matching using a test sample of 14 individuals (23 femora, 26 humeri, and 26 tibiae). Specifically, the method aims to find bilateral pairs using, as the shape signature criterion, a single 3D outline that snakes around each bone's perimeter as described by a 3D elliptical Fourier analysis function. This permits substantial 3D‐point‐cloud data reduction, that is, to 0.02% of the starting c.500,000 point cloud or just 100 points, while preserving key 3D shape information. The mean Hausdorff distance (Hd) was applied to measure the distance between each mirrored right‐side outline to every left‐side outline in pairwise fashion (132, 168 and 169 comparisons, respectively). Both thresholds and lowest Hd were investigated as pair‐match criteria, with the lowest Hd producing the best performance results for searches jointly utilizing right‐left and left‐right directions for comparison: true positive rates of 1.00 (10/10), 1.00 (12/12), and 0.92 (11/12) for the femora, humeri, and tibiae, respectively. The computational time to calculate 469 pairwise 3D comparisons on a single stock‐standard Intel® Core™ i7‐4650U CPU @ 1.70 GHz was 5 s. This short data processing time makes the method viable for real‐world application. [ABSTRACT FROM AUTHOR]

The in‐motion alignment for the underwater strapdown inertial navigation system is still a challenging problem due to various disturbances in the underwater environment. In this paper, a novel in‐motion alignment method, based on the Lie group representation, is developed. In this method, the process model is rewritten using the Lie group of the constant attitude matrix between two inertial frames as the state. An exact linear measurement model is constructed by analyzing the effect of the sensor errors in calculating the velocity vector. Next, the state‐dependent Lie group filter is designed basing on accurate derivation expressions for the covariance matrices of state‐dependent noises. The simulation and experiment results demonstrate that the proposed method can achieve better alignment accuracy and time than the existing method. The accuracy improves by 70% with the quaternion Kalman filter. [ABSTRACT FROM AUTHOR]

Summary: This paper studies the problem of recursive state estimation of stochastic linear systems with nonlinear measurements. The main idea is to rewrite the measurement map in a linear form by considering, as system output, a vector of "virtual" measurements. The result is a linear system with a non‐Gaussian and nonstationary output noise. State estimation is therefore obtained using a Kalman filter or, alternatively, a quadratic filter, suitably designed for non‐Gaussian systems. This work provides two sufficient conditions for the application of the virtual measurement approach and shows its effectiveness in the case of the maneuvering target tracking problem. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new variable control chart under type II or failure‐censored reliability tests by assuming that the lifetime of a part follows the Weibull distribution with fixed and stable shape parameter. The purpose is to monitor the mean and the variance of a Weibull process. In fact, the mean and the variance are related to the scale parameter. The necessary measures are given to calculate the average run length (ARL) for in‐control and shifted processes. The tables of ARLs are presented for various shift constants and specified parameters. A simulation study is given to show the performance of the proposed control chart. The efficiency of the proposed control chart is compared with a control chart based on the conditional expected value under type II censoring. An example is also given for the illustration purpose. [ABSTRACT FROM AUTHOR]

In this paper, we use the notion of strict Mittag–Leffler modules, in order to study the flat length of injective modules over a ring R. We show that the supremum of these flat lengths is closely related to the invariants silp R and spli R, which were defined by Gedrich and Gruenberg, as well as to the finitistic dimension of R and the injective length of the regular module. We also examine the special case where R=ℤG is the integral group ring of a group G. [ABSTRACT FROM PUBLISHER]

Maximum length measurement of the tibia has been found to be variable both in description and implementation. Historically, the literature often excludes the intercondylar eminences from the tibia in metric analysis. This paper explores the quantitative effects of inclusion or exclusion of the eminences on the maximum length measure across ancestral population, age and sex in five human adult populations of American Whites and Blacks, two Native American samples, and East Asians. A Tukey’s post hoc comparison was employed to determine the overall effect of inclusion the intercondylar eminences has on metric assessment of the tibia. Results show no significant effect on comparative analysis of the tibia by age or sex. However, the difference between sample means by ancestry is significant ( p < 0.0001). These results pose interesting questions concerning the morphological differences between ancestral groups. This investigation prompts further study of population variation of the human knee. [ABSTRACT FROM AUTHOR]

In this paper, I argue that context sensitivity is crucial for a proper exegesis of Wittgenstein's remark that one can say of the standard metre rod neither that it is one metre long nor that it is not one metre long. I discuss cases in which we can meaningfully assert that the rod in question is one metre long and explain why these cases do not conflict with Wittgenstein's insight. I analyse Pollock's recent defence of Wittgenstein's remark, as well as Kripke's objections to it, and show that, while their commentaries are helpful, blindness to context renders them unsatisfactory. [ABSTRACT FROM AUTHOR]

The method of generalized displacements (GDC) is a path-following algorithm for non-linear mechanics, capable to overcome both limit and snap-back points. It was proposed as a consistent alternative to most existing techniques, such as the arc-length family of algorithms. Although it is a reliable algorithm, it has not been as widely used as the arc-length methods, possibly because it has been seen as belonging to a different category. This paper shows that the GDC method can be seen as an orthogonal arc-length method, with an interesting constraint equation which leads to its appealing features. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary Very efficient and unbiased principles exist for estimating the total three-dimensional (3D), two-dimensional and zero-dimensional amounts of arbitrary structure in 3D space. The total one-dimensional length of real structure, in the ordinary sense, is an abstraction from the point of view of integral geometry. All stereological estimators of ‘tubular length’ are thus approximations. In addition, they are riddled by biases due to several types of artificial edges and other practical problems. This paper discusses several of these and proposes practical solutions of minimal biases. [ABSTRACT FROM AUTHOR]

The article provides gudelines for authors who want to contribute in social and cultural phenomena through their articles for the publication in the journal "Journal of Social History (JHS)." A JHS article will say something substantial and new about its empirical subject matter and will be of interest to readers beyond a specialist geographical or disciplinary audience. These guidelines brief up on the format of paper submission, the length of articles, refereeing, the possibility of acceptance of the paper. The contributions should be accompanied by an abstract of no more than 100 words, and a brief biographical note including institutional affiliation. Articles should normally be no longer than 10,000 words or 35 double-spaced standard north American letter-size pages. The contributions that are wished to be considered further after being edited, will only be sent to the external referees, and once the papers have been finally accepted, the full final text has to be sent by the authors. There are few guidelines on production and the copyright also to be taken care of by contributors.

The article provides guidelines for authors who want to contribute to social and cultural phenomena through their articles for the publication in the journal "Journal of Social History (JHS)." Articles that contribute to the historically-grounded understanding of human societies, whatever their disciplinary provenance or theoretical standpoint, will be welcomed for this journal. These guidelines brief up on the format of paper submission, presentation on the terms of the length and style of the article, references, the possibility of acceptance of the paper. The contributions should be accompanied by an abstract of no more than 100 words, and a brief biographical note including institutional affiliation. Articles should normally be no longer than 10,000 words or 35 double-spaced standard north American letter-size pages. The contributions that are wished to be considered further after being edited, will only be sent to the external referees, and once the papers have been finally accepted, the full final text has to be sent by the authors. There are few guidelines on production and the copyright also to be taken care of by contributors.

This short contribution comments on parts of a series of two papers [2] and [3] on spinodal decomposition for the Cahn-Hilliard equation In a small neighborhood of a homogeneous equilibrium u = μ of (1), with μ ϵ ℛ. in the spinodal region, we find that a strongly unstable manifold of u has dominating effects. Although this is demonstrated here for the linearized equation only, it will be essential for the nonlinear situation as well (cf. [3]). Furthermore we comment on the notion of a characteristic wavelength for the strongly unstable directions. These patterns indeed correspond to typically observed spinodally decomposed states which arise for instance in materials sciences where u corresponds to the concentration of one of the components of a binary alloy (cf. [1] or the references in [2]).where Ω C ℛ, n ∈ {1,2,3}, is a bounded domain with sufficiently smooth boundary, 0 < ϵ <<1 is a small parameter, and f is cubic-like, for example f (u) = u - u. [ABSTRACT FROM AUTHOR]

An abstract of the research paper "Assessment of crown-rump length measurement variability," by A. McLennan and colleagues is presented.