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This paper develops a general and complete solution for the undrained cylindrical cavity expansion problem in nonassociated Mohr‐Coulomb soil under nonhydrostatic initial stress field (i.e., arbitrary K0${{K}_0}$ values of the earth pressure coefficient), by expanding a unique and efficient graphical solution procedure recently proposed by Chen and Wang in 2022 for the special in situ stress case with K0=1${K}_{0}=1$. It is interesting to find that the cavity expansion deviatoric stress path is always composed of a series of piecewise straight lines, for all different case scenarios of K0 being involved. When the cavity is sufficiently expanded, the stress path will eventually end, exclusively, in a major sextant with Lode angle θ in between 5π3$\frac{{5\pi }}{3}$ and 11π6$\frac{{11\pi }}{6}$ or on the specific line of θ=11π6$\theta = \frac{{11\pi }}{6}$. The salient advantage/feature of the present general graphical approach lies in that it can deduce the cavity expansion responses in full closed form, nevertheless being free of the limitation of the intermediacy assumption for the vertical stress and of the difficulty existing in the traditional zoning method that involves cumbersome, sequential determination of distinct Mohr–Coulomb plastic regions. Some typical results for the desired cavity expansion curves and the limit cavity pressure are presented, to investigate the impacts of soil plasticity parameters and the earth pressure coefficient on the cavity responses. The proposed graphical method/solution will be of great value for the interpretation of pressuremeter tests in cohesive‐frictional soils. [ABSTRACT FROM AUTHOR]

This study investigated the role of mobile applications as aids in solving systems of linear equations with two variables through the graphical method. The use of mobile applications was examined in a group of primary and lower school students to evaluate their effectiveness in learning mathematics and improving their skills in solving systems of linear equations. The main goal of this scientific paper is to investigate and evaluate the role of mobile applications as aids in solving systems of linear equations, involving students in the research process. The research method included a mixed-methods design including quantitative analysis of mobile application results and qualitative analysis of students' experiences and opinions. Data collection was conducted through individual interviews and classroom observations. The results show that the use of these technological tools has a positive impact on the involvement of students, increasing the interest and efficiency of learning. The findings also highlight challenges and suggestions for improving the use of mobile applications in the mathematics teaching context. This study contributes to the understanding of the use of mobile technology for the development of mathematical skills at the lower secondary school level. [ABSTRACT FROM AUTHOR]

Unit distributions, exhibiting inherent symmetrical properties, have been extensively studied across various fields. A significant challenge in these studies, particularly evident in parameter estimations, is the existence and uniqueness of estimators. Often, it is challenging to demonstrate the existence of a unique estimator. The major issue with maximum likelihood and other estimator-finding methods that use iterative methods is that they need an initial value to reach the solution. This dependency on initial values can lead to local extremes that fail to represent the global extremities, highlighting a lack of symmetry in solution robustness. This study applies a very simple, and unique, estimation method for unit Weibull and unit Burr XII distributions that both attain the global maximum value. Therefore, we can conclude that the findings from the obtained propositions demonstrate that both the maximum likelihood and graphical methods are symmetrically similar. In addition, three real-world data applications are made to show that the method works efficiently. [ABSTRACT FROM AUTHOR]

Stress and deformation analysis of a cavity in an infinite/finite medium is a fundamental applied mechanics problem of interest in multiple physics and engineering disciplines. This paper develops a complete semianalytical solution for the cylindrical cavity expansion in nonassociated Mohr–Coulomb materials, by using the graphical approach and Lagrangian formulation of the cavity boundary value problem (through tracing the responses of a single material point at the cavity wall). The novelty of the new solution framework lies not only in the relaxation of the stringent intermediacy assumption for the vertical stress as usually adopted in the previous analyses, but also in the comprehensive consideration of nonhydrostatic initial stress conditions via arbitrary values of K0 (the coefficient of earth pressure at rest defined as the ratio between the horizontal and vertical initial stresses). The essence of the so-called graphical method, i.e., the unique geometrical analysis and tracking of the deviatoric stress trajectory, is fulfilled by leveraging the deformation requirement that during cavity expansion the progressive development of the radial and tangential strains must maintain to be compressive and tensile, respectively. With the incorporation of the radial equilibrium condition, the problem is formulated to solve a single first-order differential equation for the internal cavity pressure with respect to a pivotal auxiliary variable, for all the distinct scenarios of K0 being covered. Some selected results are presented for the calculated cavity pressure-expansion curve and limit cavity pressure through an example analysis. The definitive semianalytical solution proposed will be not only substantially advancing the current state of knowledge on the fundamental cavity expansion theory, but also able to serve as a unique benchmark for truly verifying the correctness and capability of the classical cornered Mohr–Coulomb constitutive model built in commercial finite element programs. [ABSTRACT FROM AUTHOR]

The powerful image analysis and statistical capabilities of computers can effectively solve problems such as insufficient precision in clastic rock particle size measurements and the heavy workload during the process. The MATLAB programming language was employed to process the samples of the Zhoutian Formation in the Upper Cretaceous of the Huichang Basin through techniques such as grayscale transformation, binarization, adaptive median filtering, and color annotation, accurately measuring their grain size parameters. The results indicate the following. The average grain size obtained using MATLAB,s direct calculation method and the graphical method are 4. 008φ and 3. 103φ, respectively. The standard deviations are 0. 8φ and 0. 803φ, the skewness values are - 0. 195φ and - 0. 041φ, and the kurtosis values are 0. 911φ and 0. 916φ. The standard deviation and kurtosis errors are small, allowing for mutual substitution between the two calculation methods, while the standard deviation and skewness errors are relatively large, making them unsuitable for mutual substitution. Both MATLAB,s direct calculation method and microscopic rock mineral identification indicate a relatively poor roundness of the Zhoutian Formation as a whole, with angular to sub-angular clastic particles. The sedimentary environment discrimination formula reflects the formation of the Zhoutian Formation in a fluvial depositional environment, consistent with the geological background and microscopic observation results. Through the MATLAB programming language, it is possible to accurately identify particle outlines and calculate various parameters in clastic rocks, providing great convenience for sediment grain size research, eliminating subjective interference, and improving work efficiency [ABSTRACT FROM AUTHOR]

Single-point incremental forming (SPIF) has emerged as a cost-effective and rapid manufacturing method, especially suitable for small-batch production due to its minimal reliance on molds, swift production, and affordability. Nonetheless, SPIF's effectiveness is closely tied to the specific characteristics of the employed sheet materials and the intricacies of the desired shapes. Immediate experimentation with SPIF often leads to numerous product defects. Therefore, the pre-emptive use of numerical simulations to predict these defects is of paramount importance. In this study, we focus on the critical role of the forming limit curve (FLC) in SPIF simulations, specifically in anticipating product fractures. To facilitate this, we first construct the forming limit curve for Al1050 sheet material, leveraging the modified maximum force criterion (MMFC). This criterion, well-established in the field, derives FLCs based on the theory of hardening laws in sheet metal yield curves. In conjunction with the MMFC, we introduce a graphical approach that simplifies the prediction of forming limit curves at fracture (FLCF). Within the context of the SPIF method, FLCF is established through both uniaxial tensile deformation (U.T) and simultaneous uniform tensile deformation in bi-axial tensile (B.T). Subsequently, the FLCF predictions are applied in simulations and experiments focused on forming truncated cone parts. Notably, a substantial deviation in fracture height, amounting to 15.97%, is observed between simulated and experimental samples. To enhance FLCF prediction accuracy in SPIF, we propose a novel method based on simulations of truncated cone parts with variable tool radii. A FLCF is then constructed by determining major/minor strains in simulated samples. To ascertain the validity of this enhanced FLCF model, our study includes simulations and tests of truncated cone samples with varying wall angles, revealing a substantial alignment in fracture height between corresponding samples. This research contributes to the advancement of SPIF by enhancing our ability to predict and mitigate product defects, ultimately expanding the applicability of SPIF in diverse industrial contexts. [ABSTRACT FROM AUTHOR]

This paper attempts to expand the graphical analysis concept proposed by Chen and Abousleiman (Géotechnique, 2022. https://doi.org/10.1680/jgeot.21.00172) to deduce the undrained expansion solution of a cylindrical cavity in shear strain-hardening Drucker–Prager frictional soil. Based on the geometrical representation of the stress state/path and strain increments in the deviatoric planes, it is shown that the deviatoric stress-Lode angle stress path can be desirably determined by solving a first-order differential equation for the stress ratio (deviatoric stress over mean effective stress) in term of the Lode angle. The essential cavity expansion curve may also be readily constructed by calculating the internal cavity pressure and the corresponding expanded cavity radius, respectively, through simple numerical integrations with respect to the same variable of stress ratio. In particular, the ultimate cavity pressure can be easily evaluated by directly integrating the expression for cavity pressure with the stress ratio up to its limiting value. Some numerical results obtained from the proposed graphical method are presented to illustrate the impacts on the cavity responses of the earth pressure coefficient at rest, K 0 , and the key plasticity hardening parameters, which have also been compared with alternative solutions that require dealing with a system of coupled differential equations involving three principal effective stress components. [ABSTRACT FROM AUTHOR]

In this study, we propose two estimators called the 3-step modified maximum likelihood (MML) and the combined estimators of the parameters of the modified Weibull distribution which is used in reliability models with bathtub-shaped failure rate function. The simulations show the superiority of both estimators over the graphical estimators. Particularly, the combined estimators are the better of the two. Two real-life data applications also show the superiority of the proposed estimators compared to the graphical estimators. [ABSTRACT FROM AUTHOR]

The fanning compression stress pattern in RC deep beams under uniform load presents a challenge to formulating the configuration of strut‐and‐tie model (STM). To this end, this paper proposes an alternative method for creating a graphical discontinuous stress field model (DSFM) to fill up the whole beam continuum. It comprises a certain number of trapezoidal stress‐bands with varying bandwidths, and their stress values can be calculated based on force equilibrium conditions. Several stress subfields are defined through a certain stress combination from several directions. The DSFM is implementable for both service limit state (SLS) and ultimate limit state (ULS) in that its configuration is primarily oriented by elastic stress field and only a limited plastic redistribution is allowed for plastic failure. The graphical procedure of DSFM is demonstrated and examined by a test deep beam example, which shows that the predictions are fairly in good agreement with the test results. [ABSTRACT FROM AUTHOR]

Ellipsometrically obtained spectral dependences of ordinary αxy and extra-ordinary αz extinction/attenuation coefficients within the spectral range λ = 300…980 nm of uniaxially anisotropic polytetrafluoroethylene (PTFE) films were analyzed. We considered the capabilities and specific features of the graphical representation technique for determining the contribution of Rayleigh scattering and Urbach absorption to light attenuation in the spectral range beyond fundamental absorption. It has been shown that the graphical approach enables to estimate these contributions qualitatively, semi-quantitatively or quantitatively, depending on the situation. The conclusions made using the analysis of graphical representation are confirmed by numerical solution of the inverse problem via simulation of the αxy (λ), αz (λ) experimental dependences within the framework of a best-fit procedure. Being based on both of these approaches, we have ascertained that, in the as-prepared PTFE films, the so-called anomalous light scattering (ALS) with the spectral dependence of scattering coefficient αs ≈ as λ–p (p > 4) takes place. Transformation of scattering from ALS to the Rayleigh one with p ≅ 4 due to annealing is accompanied by an increase of Urbach (subband) absorption. Both of these factors cause narrowing the dynamic range of extinction coefficient values. Both scattering and absorption coefficients are higher for the component of light polarized along the normal to the substrate as compared to the component polarized in parallel to it. The relationship between observed behavior of the scattering and absorption coefficients and the film structure has been discussed. [ABSTRACT FROM AUTHOR]

The Bayesian approach is applied to estimation of the Weibull-power law process (WPLP) parameters as an alternative to the maximum likelihood (ML) method in the case when the number of events is small. For the process model considered we propose to apply the independent Jeffreys prior distribution and we argue that this is a useful choice. Comparisons were also made between the accuracy of the estimators obtained and those obtained by using other priors—informative and weakly informative. The investigations show that the Bayesian approach in many cases of a fairly broad collection of WPLP models can lead to the Bayes estimators that are more accurate than the corresponding ML ones, when the number of events is small. The problem of fitting the WPLP models, based on ML and Bayes estimators, to some real data is also considered. It is shown that the TTT-concept, used in the reliability theory, is not fully useful for the WPLP models, and it may be so for some other trend-renewal processes. In order to assess the accuracy of the fitting to the real data considered, two other graphical methods are introduced. [ABSTRACT FROM AUTHOR]

The pinch analysis technique circumvents the drawbacks of local optima in the design of production processes and determines energy targets from a systemic design perspective. It has now evolved into a comprehensive methodology for process industry integration. As research deepens in traditional industrial domains, the exploration of applications in emerging fields is gradually expanding. However, solely relying on the analysis and summarization within a singular domain is insufficient for driving broader applications across diverse fields. Therefore, this paper discusses the pinch analysis techniques across various fields, from energy exchange networks to mass transfer networks. By examining their technical principles and categorizing method types, different technologies are horizontally compared, and their key characteristics are revealed. Subsequently, this paper explores future development directions and imminent challenges of the pinch analysis technique in power systems, aiming to offer new perspectives for expansion and to address existing issues such as load balance analysis, planning rationality, and reliability assessment in power systems. • Pinch analysis methods in various fields are analyzed comprehensively. • Analogous graphic methods and numerical methods of pinch analysis are compared across different fields respectively. • The underlying mathematical structure of pinch analysis techniques and principle of graphical methodology are revealed. • The prospects and a novel approach to applying pinch analysis in power systems are proposed. [ABSTRACT FROM AUTHOR]

This paper presents a design for five conventional superconducting magnet structures to meet the high magnetic load demand of superconducting motors while reducing the superconducting tapes consumption. A 45° highest efficiency line is proposed based on the graphical method, and the magnet structure is optimized by combining finite element and PSO algorithms. Additionally, a correlation function is established using the vertical magnetic field to estimate the critical current, describing the nonlinear relationship between the two. The optimization method can maintain the airgap flux density waveform before and after optimization, reduce tapes consumption and perpendicular field on the tapes, refine the field distribution, and improve the safety margin of superconducting coils. The magnet design scheme can be selected with low tape consumption or high safety margin according to actual demand. This research can be used to optimize the electromagnetic design of superconducting electric motors, as well as other superconducting magnet applications, such as superconducting magnetic bearings, nuclear magnetic resonance, and large-scale scientific installations for high-energy physics. The aim is to achieve the exhaustive use of superconducting tapes. [ABSTRACT FROM AUTHOR]

This paper presents analytical solutions for the finite expansion problems of a spherical or cylindrical cavity, using a simple yet novel graphical approach recently proposed by Chen & Abousleiman in 2022, in both original Cam Clay (OCC) and modified Cam Clay (MCC) soils under undrained conditions. It is shown that, for a soil mass subjected to isotropic in situ stress conditions, the stress paths in the deviatoric plane for the spherical and cylindrical cavity expansions turn out to be two straight lines, which correspond to Lode angles equal to 11π6$\frac{{11\pi }}{6}$ and 5π3$\frac{{5\pi }}{3}$, respectively. The desired limiting cavity pressure therefore can be directly and accurately evaluated through simple numerical integration with respect to the mean effective stress, while the relationship between the internal cavity pressure and the cavity radius, the cavity expansion curve, may be equally conveniently determined. Numerical results obtained from the current graphical method, for a range of the values of over consolidation ratio considered, compare extremely well with those from the conventional semianalytical formulations of the undrained cavity problem that involve solving a system of coupled governing differential equations. It is interesting to note that the representative and approximate solution developed by Collins & Yu in 1996 indeed is a correct one for the spherical cavity expansion problem, and, with minor modifications, will be applicable for the accurate calculation of the responses of the cylindrical cavity as well. [ABSTRACT FROM AUTHOR]

The study of phase transitions and critical parameters has a history of nearly one century. The interest shown in this field of science has provided an accumulation of knowledge about phase transitions and critical states of matter through significant researches. On the other hand, theoretical and experimental studies still show that the pressure and temperature diagram of the material is not completed. In particular, the absence of plasma in the (p-T) phase diagram, the uncertainty of the pressure-dependent boundary range of the liquid phase and the state of the equilibrium curves are the focus of the studies. In the phase diagram of pure substance (p-T), the representation of only three phases and the boundary curves separating these phases with two basic points limits the phase diagram. However, as long as the plasma, which constitutes 98% of the universe and is accepted as the fourth phase of matter, does not take place in the phase diagram (p-T) and the liquid phase remains uncertain, phase transitions and critical parameters cannot be fully resolved. [ABSTRACT FROM AUTHOR]

In the present work, a new method for the determination of the outrigger loads in mobile cranes is proposed. The approach adopted assumes the mobile crane as a rigid body and the ground having a linear elastic behavior. The outrigger reactions are determined, using the concept of complete support pattern, through the calculation of the area of triangles constructed within it. The main feature of the method is that the determination of the outrigger reactions can be done by means of graphical considerations with the advantage to perform the task quickly and without the use of complicated calculations. The knowledge of the outrigger pattern, the resultant of all the forces applied and the center of mass of the system crane-payload are only needed as input data. Although the method is suitable for cranes with an outrigger system of any number and shape, the simplification deriving from the use of the graphical approach is fully available only for an outrigger system with four outriggers having a specific shape. These configurations, however, represent the most common configuration found in real applications. The validity of the method proposed has been proven comparing the results with data available in the cranes' manuals and with actual reactions of the outriggers of a mobile cranes operating on site. [ABSTRACT FROM AUTHOR]

Reinforced concrete beams lose resistance at high temperatures and so as to guarantee their good performance, it is mandatory to consider this accidental action in design. As an alternative to the methods proposed by the European and Brazilian standards, above all the tabular method that, despite its simple application, limits calculations to a few pre-defined values, a new tool for fire design of these beams is proposed herein. A graphical method was developed with the Temperature Calculation and Design (TCD) software, which performs transient bi-dimensional thermo-structural analysis using the finite element method. The main variable of this method consists of the resistance to the bending moment of a heated cross-section. For its validation, the moment of four rectangular sections was determined according to four simplified methods. These results were compared among themselves and to those obtained by a more advanced method. They were all verified to lead to similar results. With regard to the TCD, whose results were used for the preparation of the graphical method, the maximum difference compared to a more advanced method was approximately 2.5%. After validation, graphs that associate the ratio between the applied moment in fire and the resistance to bending moment at ambient temperature to the fire resistance for different beams were created. These graphs present design solutions for more than 2300 beam models with T-shaped cross-sections in assorted lengths, heights, covers and reinforcement arrangements, both positive and negative. In the application examples, the results from the graphical method were generally more economic when compared to the tabular method of the fire design standards. [ABSTRACT FROM AUTHOR]

Permutation methods are commonly used to test the significance of regressors of interest in general linear models (GLMs) for functional (image) data sets, in particular for neuroimaging applications as they rely on mild assumptions. Permutation inference for GLMs typically consists of three parts: choosing a relevant test statistic, computing pointwise permutation tests, and applying a multiple testing correction. We propose new multiple testing methods as an alternative to the commonly used maximum value of test statistics across the image. The new methods improve power and robustness against inhomogeneity of the test statistic across its domain. The methods rely on sorting the permuted functional test statistics based on pointwise rank measures; still, they can be implemented even for large data. The performance of the methods is demonstrated through a designed simulation experiment and an example of brain imaging data. We developed the R package GET, which can be used for the computation of the proposed procedures. [ABSTRACT FROM AUTHOR]

In this study, the coefficients of Weibull Distribution Function (WDF) were calculated at two different heights using by six different methods. One-year wind data were used to determine the coefficients of WDF at different heights, and the wind data were obtained from a metrology station with a height of 10 m and a real wind turbine with a height of 80 m in Turkey's Hatay region. The used methods in this study were Graphical Method (GM), Empirical Method, Energy Pattern Method (EPM), Energy Trend Method, Maximum Likelihood Method and Moment Method.\ Three different statistical error analysis tests were used to compare the performance of the used methods at two different heights. Estimated mean wind speed and power values are the most important indicators to evaluate the performance of the used methods. In this study, mean wind speeds and powers were estimated in all methods for both heights using the WDF. These obtained values were compared with the actual real data and the best performing method was determined at both different heights for selected region. When the results were evaluated in general at both different heights, it was seen that the best performance method was the EPM and the worst performance method was the GM. [ABSTRACT FROM AUTHOR]

• A comprehensive decision support system to characterize tails of probability distributions is proposed. • The robustness of proposed DSS is evaluated through a simulation experiment. • The utility of the DSS is demonstrated through its application to Indian precipitation data. • Precipitation analysis (4801 stations) shows around 98% of records have heavy tails over India. A conventional Decision Support System (DSS) can be used to characterize tails of probability distributions into distribution families using various graphical methods. Existing DSSs lack efficient segregation of the Lognormal distribution from the Regularly varying and Subexponential distribution families. Also, they lack the ability to identify the distributions from the hyper-exponential distributions. Recently developed graphical diagnostic tools, such as concentration profile, concentration adjusted expected shortfall, discriminant moment ratio plot, maximum-to-sum plot, and Zenga plot can classify the tails of distributions into various classes if used in an appropriate order in combination with tools of conventional DSS. The present study proposes a comprehensive DSS that alleviates the shortcomings associated with the conventional DSS and characterizes the tails of distributions into classes B\A (Pareto type), C\B (regularly varying), D\C (subexponential), E (Exponential type), hyper-exponential class (outside class E) and LN (Lognormal) distribution (the limiting case between class C and D). The robustness of the proposed DSS over the conventional DSS is established through a simulation experiment. Further, this study also evaluates the influence of the sample size on the effective implementation of the proposed DSS. Finally, the proposed DSS is applied to characterize the tails of daily gridded precipitation data over India. Results indicate that precipitation data from about 98% of grids over India exhibit distributions from heavy-tailed families. The study recommends the use of heavy-tailed distributions to model daily precipitation data over India. The study also suggests that one should rely on more than one graphical method for deducing rational conclusions regarding tail characterization. [ABSTRACT FROM AUTHOR]

This paper proposes a simple and fast method to obtain the aeroelastic response of a square cylinder following different modelling approaches underpinned by a novel graphical technique that establishes abstract relationships between different key physical parameters involved in the mathematical models. The method is applied to the analysis of three important aeroelastic problems in the crosswind response of a square cylinder, including the transverse galloping defined with a quasi-steady model, the vortex-induced vibration (VIV) using a nonlinear oscillator model, and the VIV-galloping interaction following a combined effects model. The results demonstrate that the proposed analytical method simplifies the analysis and it is able to capture most of the complex aeroelastic crosswind behaviors of a square bluff body. • A graphical method to obtain the aeroelastic response of a square cylinder following different modelling approaches is proposed. • Compared with conventional analytical methods, the new analytical method has advantages of simplicity and effectiveness. • The graphical analytical method is successfully applied to the study of transverse galloping, VIV and their potential interaction. [ABSTRACT FROM AUTHOR]

Techniques of pile installation such as jacking, dropping weight, vibration, and explosion were applied but these methods were discovered to have weaknesses, such as high friction resistance and high settlements. To overcome these problems, this study introduces new method of pile installation which is Jacking and Rotary method (J&R). The objective of this study is to determine pile behaviour for static load test using common method namely jacking (J), and a new method, J&R through the ultimate pile capacity achieved by both methods. A stainless steel 25 mm circular pile, a 50 mm circular pile and a screw pile were used as test piles for this investigation. To achieve the objectives, this study employed graphical methods such as Brinch Hansen 80% and Tangent method to determine the ultimate pile capacity for both piling installation methods. Results revealed that for jacking method, the highest ultimate pile capacity value for the 50 mm circular pile was 1.186 kN, whereas the 25 mm circular pile had the lowest pile capacity reading of 0.539 kN. Screw pile shows the reading of 1.068 kN for its pile capacity. While for J&R, the highest average for both graphical methods are screw pile with 0.683 kN, while the 50 mm circular pile produced the lowest pile capacity which was 0.491 kN. For 25 mm, pile capacity using J&R is 0.543 kN. Result shows the acceptable for J&R methods to be introduced with further investigation such as the response of pile under axial loading and others. • Command methods for piling installation which could lead the structure to fail. • Jacking and Rotary pile installation simultaneously turned and jacked into the ground. • Brinch Hansen 80% and Tangent method used to determine the ultimate pile capacity. • Results indicated the acceptable of J&R methods and suggest for further investigation. [ABSTRACT FROM AUTHOR]

In the essence of climate change, a better understanding of the variation in precipitation patterns provides in-depth knowledge of water resource management and mitigation of floods and droughts, particularly in Morocco where rainfed agriculture is predominant. This paper investigates the precipitation variability over the whole country of Morocco. To that end, a monthly precipitation dataset of 78 rain gauges with more than 40 years of observation was used to investigate the spatial-temporal variability of precipitation. Moreover, the spatio-temporal trends variation was also assessed through a comparative analysis of the various trend detection methods (both old and new tests). The new methods were used also to identify non-monotonic sub-trends. The results highlighted that (1) Morocco has experienced considerably larger variations regarding the temporal variability of precipitations and their spatial distribution during the last few decades; (2) the greatest variability of precipitation was observed moving latitudinally from humid to arid regions; (3) the annual precipitation exhibited positive and negative trends where there was no clear evidence of upward or downward trends. The significant trends are identified for 5(6,41%), 6 (7,69%), 3 (3,84%), and 65 (83%) stations from the results of the MK test, SR test, Onyutha's method, and ITA method, respectively. (4) the MK, SR, and Onyutha methods exhibited similar trends which indicate that are in perfect concordance. The ITA method showed also some resemblance with the results of other methods even though it proved to be over-sensitive in determining trend significance; and (5) the highlands with a Mediterranean climate are prone to flooding whereas the regions with desertic and semi-arid climates are prone to drought. Overall, our findings allow policy-makers to properly design adaptation strategies for changing precipitation patterns as well as increasing extreme events (floods and droughts). • Data from 78 rain gauges were used to investigate precipitation variability over Morocco. • Precipitations are becoming increasingly variable and uneven moving latitudinally from humid to arid regions. • Potential exacerbation of floods in Mediterranean zones, while arid and semi-arid zones will face drought conditions. • The statistical-graphical methodology is the most appropriate approach for detecting precipitation trends and sub-trends. • Our results allow to develop proper adaptation strategies for changing precipitation pattern and increasing extreme events. [ABSTRACT FROM AUTHOR]

• This article reports for the first time. • The reactivity of both synthetic slag and commercial slag covering the common composition range. • The role of sulfur species in slag on the calorimetric measurement. • A novel graphical method to estimate the reactivity of slag. In this paper, both synthetic slag and commercial slag covering the common composition range were employed to estimate the correlation between slag chemistry and reactivity through hydraulicity and dissolution tests. It was found that slag reactivity was favorably affected by increasing Al 2 O 3 and MgO contents, while the adverse effect of decreasing CaO/SiO 2 ratio could be compensated by higher amounts of Al 2 O 3 and/or MgO. When calorimetric measurement was used to assess the reactivity of slag, the effect of sulfur species incorporated in commercial slag should be taken into consideration as a small quantity of it could lead to a major difference of cumulative heat release due to the formation of ettringite. Moreover, a novel graphical method was proposed to estimate the reactivity of slag considering its chemical composition from a new perspective, i.e. a cartesian coordinate system based on (CaO/SiO 2)−(MgO + Al 2 O 3). [ABSTRACT FROM AUTHOR]

Chemical absorption method plays an important role in the process of CO 2 separation. One major problem for chemical absorption is huge energy consumption, which is affected by the performance of absorbents. Developing a type of absorbent with high absorption capacity and low regenerative energy consumption is a research topic that attracts attention. The combination of two or more amines is one way to develop new solvents. However, the change of amine liquid ratio can cause a series of complex nonlinear changes in absorption capacity, absorption heat, the heat of vaporisation and sensible heat. It is of interest to visualise the amine solution mixing ratio optimisation to help reduce the energy consumption and increase the absorption capacity. Derivative analysis of standardised vs variables diagram (DSVD), a kind of graphical method based on maximum benefit and minimum consumption, is proposed to determine the optimal mixing ratio of binary amine solution. This novel approach helps to visualise what kind of amines are not suitable for compounding, what kind of amines have the best compounding ratio, and how to determine the optimal compounding ratio. The optimal mixing ratio of the Methyldiethanolamine (MDEA) - Piperazine (PZ) system and MDEA - Monoethanolamine (MEA) were optimised by this method. The optimal ratio of MDEA - PZ and MDEA - MEA are 0.6 (PZ: MDEA = 0.6:0.4, wt.%) and 0.8 (MEA: MDEA = 0.8:0.2, wt.%). • Derivative analysis of standardised vs variables diagram (DSVD) is proposed. • A new method to determine the optimal mixing ratio of binary amine solution. • Multi-objective graphic solution based on benefit and consumption. • The mixing ratio of MDEA + MEA system and MDEA + PZ system was optimised. [ABSTRACT FROM AUTHOR]

Several international institutions have defined background or baseline levels to assess heavy metal concentrations on marine sediments in order to use these values as a reference for sediment quality indices. This criterion for marine sediment quality is applied to evaluate the potential risk of pollutants in aquatic ecosystems. However, those values were established using samples collected in large areas which present specific geochemical conditions. Then there may be a lack of accuracy in the results when using these parameters in other areas. In this context, 15 sediment cores (8 cm diameter; 2 m length) were recovered along the 400 km Asturian coastline, which is an area with representative lithological conditions for the Bay of Biscay, to determine more precise baseline levels for marine sediments from the Bay of Biscay. An evaluation of statistical and empirical methods was done to determine which method delivers the best results. Statistical methods such as mean±2SD and median±2* Median Absolut Deviation (MAD) are strongly influenced by outliers and data distributions which make these approaches less robust. Graphic techniques such as Cumulative Distribution Function (CDF) avoid the problems that asymmetrical data distributions may cause but introduce a certain level of subjectivity in the results due to the baseline values obtained depending on the researcher's experience. Finally, the Probability Curve (CP) method solves issues which may occur when using other techniques and allows one to establish baseline levels based on different percentiles. Regarding the features of the data analysed in this study, the baselines obtained via the CP method with the 95th percentile appear to be the most accurate for the Bay of Biscay. A wide variation has been found between the new baseline values and other international and national levels. Disparity between those levels and the baselines obtained in this study can be generated by granulometric and geological factors. The notable increase in Hg baseline values with respect to OSPAR Background Concentration values (BCs) (0.05 μg g−1 and 0.6 μg g−1 respectively) and the huge different with CEDEX levels and new threshold levels (0.35 μg g−1 and 1.2 μg g−1 respectively) emphasised the relevance of defining specific baselines and threshold levels, as the ones obtained in this study, not only to obtain more precise criteria for marine sediment quality to be used in environmental assessments, but also to propose new threshold levels for the evaluation of dredged material before dumping into ocean sites. • 95th percentile on Probability Curve method determine the most accurate baselines. • Regional geological diversity causes baselines very different from OSPAR. • Natural Hg concentrations were twelve times higher than the OSPAR level. • Recalculated Hg Spanish sediment management level was 3 times the actual value. • Specific baselines and threshold levels are needed to get accurate assessments. [ABSTRACT FROM AUTHOR]

The purpose of this study is to introduce and demonstrate a novel graphical method to determine effective bremsstrahlung focal spot size and shape of the therapeutic beam from a linear accelerator. The energy distribution within the beam spot allows in determining effective bremsstrahlung size and shape of beam spot. The transverse and radial dose profiles were measured for a range of field sizes in an isocentric setup. The Length of direct focal region (LDFR) on either side of profiles were determined through the de-convolution of dose profile. The graph plotted for LDFR versus field size helps in determining properties of beam spot. The dimensions of FWHM of effective bremsstrahlung focal spot were found elliptical in nature close to the order of 1 mm. This method allows determination of FWHM of the effective bremsstrahlung focal spot that fairly falls within the range of dimension of FWHM of beamspot published in literature. [ABSTRACT FROM AUTHOR]