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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]

Critical values of boron (B) for wheat nutrition in soil and plant were determined through a pot experiment with twenty-one surface soils of Alluvial flood plain and Red-latertic belt comprising three major soil orders (Entisols, Alfisols, Inceptisols) with four levels of boron. Application of boron significantly increased the dry matter yield as well as uptake of B by plants. Critical concentration of hot calcium chloride (CaCl2) extractable B in soil for wheat was found to be 0.53 mg kg−1. The critical plant B concentration varied with growth stages and values were 7.4 mg kg−1 at panicle initiation and 4.18 mg kg−1 at maturity, respectively. The findings of this investigation also recommend the application of 2 kg B−1 ha−1 for ensuring B sufficiency to wheat in Indo-gangetic alluvial and Red-Lateritic soils. [ABSTRACT FROM AUTHOR]

This paper investigates the implementation of an analytical model to determine the porosity of a granular material during reactive and nonreactive sintering. A graphical interpretation of this model is proposed to calculate the porosity by comparing the experimental shrinkage curve with the ideal one. For the nonreactive sintering, some examples have been taken from the literature to illustrate the application of this method for two granular materials (alumina and zircon). In the case of reactive sintering, we have used our experiments to study the sintering behavior of magnesium hydroxide. The shrinkage curve was determined by dilatometer and the porosity was measured by helium pycnometer. The comparison revealed that the porosity calculated from the model is fully consistent with the porosity measurements in the both cases. [ABSTRACT FROM AUTHOR]

The 19th century graphic method of Eddy-Lévy is analyzed and proposed in an analytical form as an assessment tool for masonry domes. The method determines the neutral hoop that separates the upper part of the dome that behaves as a compressed membrane from and the bottom that behaves as independent arches, due to the presence of vertical cracks. This method allows determining a no-tension equilibrated solution, accounting for the natural behavior of masonry domes of fracturing along meridian planes. Six case studies were investigated, considering spherical and pointed dome, complete, with hole and with hole and lantern. A modified version has been studied to model the biaxial stress of upper part properly through the membrane theory, and compared to the solution obtained by a numeric discrete block model. Limit thickness-to-radius ratio was identified, and a parametric analysis was carried out to investigate the extension of meridian fracture varying dome shape and thickness. [ABSTRACT FROM PUBLISHER]

An empirical relation between the heat of formation of molecular ions and cation size is used to study the effects of methyl and ethyl substitution of hydrogen atoms on the cations of the CnHmhydrocarbons methyl, methylene, acetylene and ethene. The results provide tests of the graphical method, revealing regularities and irregularities in the empirical size relation used, as well as its value as a predictive tool for determining cation and neutral heats of formation. Of the 36 CnHmcations studied, only 5 have heats of formation listed in the renowned ATcT tables. Some CnHmcation heats of formation are questioned or eliminated, mainly in cases where multiple choices are available in the literature. Proposals are made for investigating or re-investigating the ionisation energies and the heats of formation of several of the molecules studied where no data previously exist or where our analysis suggests that more reliable values are needed. The relative effects of methyl and ethyl substitution on the thermodynamic stability of the series of alkyl-substituted CnHmcations are discussed. [ABSTRACT FROM AUTHOR]

This article presents individual conditional expectation (ICE) plots, a tool for visualizing the model estimated by any supervised learning algorithm. Classical partial dependence plots (PDPs) help visualize the average partial relationship between the predicted response and one or more features. In the presence of substantial interaction effects, the partial response relationship can be heterogeneous. Thus, an average curve, such as the PDP, can obfuscate the complexity of the modeled relationship. Accordingly, ICE plots refine the PDP by graphing the functional relationship between the predicted response and the feature forindividualobservations. Specifically, ICE plots highlight the variation in the fitted values across the range of a covariate, suggesting where and to what extent heterogeneities might exist. In addition to providing a plotting suite for exploratory analysis, we include a visual test for additive structure in the data-generating model. Through simulated examples and real datasets, we demonstrate how ICE plots can shed light on estimated models in ways PDPs cannot. Procedures outlined are available in the R packageICEbox. [ABSTRACT FROM AUTHOR]

In product development processes and in the engineering world in general, many situations arise in which a decision must be taken to choose the best alternative or concept from among several already existing ones. Among the most used methods in situations like these are those that use two-dimensional decision matrices, where the concepts or alternatives are compared by evaluating them according to the degree of compliance for preestablished quality criteria. The finally adopted decision is not only conditioned by the decision maker's assessment of each alternative but also by the weightings initially assigned to the criteria. This means that variation in the assessment of any alternative or in the weighting of a criterion can lead to a distinct alternative being selected. In this article, we propose a graphical method that makes it simpler to view the margin for variation, for both the assessments of the alternatives and the weightings for the quality criteria, that does not affect the finally adopted decision. In this way, the decision-making team can analyze in greater depth the more critical assessments and weightings that, although consisting of small changes, could affect the decision. Finally, the applicability of the proposed method is demonstrated in a case study involving an electrical switch design. [ABSTRACT FROM PUBLISHER]

In this paper, a new life test plan called a progressively first-failure-censoring scheme introduced by Wu and Kuş [On estimation based on progressive first-failure-censored sampling, Comput. Statist. Data Anal. 53(10) (2009), pp. 3659–3670] is considered. Based on this type of censoring, the maximum likelihood (ML) and Bayes estimates for some survival time parameters namely reliability and hazard functions, as well as the parameters of the Burr-XII distribution are obtained. The Bayes estimators relative to both the symmetric and asymmetric loss functions are discussed. We use the conjugate prior for the one-shape parameter and discrete prior for the other parameter. Exact and approximate confidence intervals with the exact confidence region for the two-shape parameters are derived. A numerical example using the real data set is provided to illustrate the proposed estimation methods developed here. The ML and the different Bayes estimates are compared via a Monte Carlo simulation study. [ABSTRACT FROM PUBLISHER]

The process capability index Cpk is widely used when measuring the capability of a manufacturing process. A process is defined to be capable if the capability index exceeds a stated threshold value, e.g. Cpk>4/3. This inequality can be expressed graphically using a process capability plot, which is a plot in the plane defined by the process mean and the process standard deviation, showing the region for a capable process. In the process capability plot, a safety region can be plotted to obtain a simple graphical decision rule to assess process capability at a given significance level. We consider safety regions to be used for the index Cpk. Under the assumption of normality, we derive elliptical safety regions so that, using a random sample, conclusions about the process capability can be drawn at a given significance level. This simple graphical tool is helpful when trying to understand whether it is the variability, the deviation from target, or both that need to be reduced to improve the capability. Furthermore, using safety regions, several characteristics with different specification limits and different sample sizes can be monitored in the same plot. The proposed graphical decision rule is also investigated with respect to power. [ABSTRACT FROM AUTHOR]

It is shown in this study the graphical analysis using velocity polygons may be used to locate direct singular positions of a limited degree-of-freedom (DOF) parallel manipulator. The three DOF parallel manipulator MIPS is treated for illustration. The conditions for the moving platform to become movable under zero driving speeds can be obtained using the graphical velocity analysis. Manipulator configurations satisfying these conditions are direct singular positions. Several direct singular positions are determined using this technique. In order to verify these singular positions, Jacobian matrix for this manipulator is also derived in this study, and singular positions determined from graphical analysis can make the Jacobian matrix singular. [ABSTRACT FROM AUTHOR]

In this article we consider the problem of testing for parameter changes in ARIMA models based on the cusum test. The proposed test procedure is applicable to testing for the change from stationary models to non stationary models, and vice versa. The idea is to transform the time series via differencing to make the whole time series as a combination of stationary subseries. For this task, we propose a graphical method to identify the right order of differencing. Then the cusum test statistic proposed by Lee et al. (2003) is constructed based the differenced time series. Simulation study and real data analysis are provided for illustration. [ABSTRACT FROM AUTHOR]

In clinical endpoint trials, the association between a baseline covariate and the risk of an endpoint is often measured by the hazard ratio as calculated by a Cox regression model, and illustrated by Kaplan-Meier curves comparing cohorts defined by levels of the covariate. The Cox regression model is easily extended to the case of time-varying covariates; however, there is no clear approach for similarly extending the standard Kaplan- Meier estimator. Various ad hoc procedures that have been used in the medical literature are seriously flawed. This article discusses an extended Kaplan-Meier estimator that can be used with time-varying covariates and illustrates this method using data from a long-term clinical trial. [ABSTRACT FROM AUTHOR]

Azeotropic distillation as an early and important special distillation process is commonly used in laboratory and industry. It can be used for separating the mixture with close boiling point or forming azeotrope. This paper tries to provide a review on azeotropic distillation for general readers, focusing on entrainer selection and mathematical models. Since the 1950s, along with extractive distillation, azeotropic distillation has gained a wide attention. Like extractive distillation, the entrainer, i.e., the third component added to the system, is also the core of azeotropic distillation. In the process design and synthesis, the graphical method (in most cases refer to as triangular diagram) is often employed. But it is better to take on the results from graphical method as the initial values of rigorous equilibrium (EQ) stage/non-equilibrium (NEQ) stage models. One outstanding characteristic of the EQ/NEQ stage models different from extractive distillation and catalytic distillation is to describe phase split for heterogeneous azeotropic distillation. In general, the operation process is very sensitive to some parameters in the case of more than one azeotrope formed, and thus the phenomenon of multiple steady states (MSS) tends to appear. [ABSTRACT FROM AUTHOR]

The spline smoothing approach to nonparametric regression is extended to cover the estimation of curves that branch at certain specified points in time. This extension is motivated and illustrated by data from an experiment on sunflowers. Apart from providing insight into this particular data-analytic problem, the work described demonstrates the power of the roughness penalty approach in coping with curve estimation of a nonstandard kind. Particularly in the context of certain experiments in horticulture and arboriculture, the experimental material may be treated identically to the control up to a certain known time part of the way through the experiment. To display and investigate the effect of treatments applied during growth it is of interest to estimate a branching curve. In the simplest case we want to study two growth curves that are common up to a certain known time and then diverge (or branch) after the application of a treatment to part of the experimental material. The spline-smoothing approach to nonparametric regression as discussed, for example, by Silverman (1985) can be extended to deal with branching curves by defining a roughness penalty that measures the local variation in all branches of the curve system. The usual residual sum of squares is penalized by the addition of a multiple of this roughness penalty, and the resulting penalized sum of squares can be minimized. The solution branching curve is made up of a number of cubic spline branches that fit together according to rules that are derived in the present article and that allow the curve system to be found by solving a set of sparse linear equations. A nonparametric approach to this curve estimation problem is virtually essential, because it is hard to contemplate extensions of the usual parametric growth curve models that allow for branching curves in any way that is not rather artificial.... [ABSTRACT FROM AUTHOR]