Simple Graphical Method Research Articles

Determination of Donor Densities and Donor Levels in 3C-SiC Grown from Si2(CH3)6 Using Hall-Effect Measurements

Without any assumption of the number of types of impurities, the densities and energy levels of donors in undoped 3C-SiC grown from Si2(CH3)6 are precisely determined by the simple graphical method proposed here, using the temperature dependence of the majority-carrier concentration obtained by Hall-effect measurements. We detect at least three types of donors whose energy levels (ΔED) are 7–14 meV, 46–54 meV and 97–120 meV as measured from the conduction band, although it was reported that ΔED for nitrogen atoms decreased with an increase in the donor density from ∼50 meV to ∼15 meV. In addition to the ∼15 meV donor that was reported in undoped 3C-SiC grown from a mixture of SiH4 and C3H8, at least two donor levels are detected in undoped epilayers grown from Si2(CH3)6. From the viewpoints of donor density and compensation ratio, the quality of undoped 3C-SiC grown from Si2(CH3)6 is better than that of undoped 3C-SiC grown from a mixture of SiH4 and C3H8.

Theory and Applications of Hazard Plotting for Censored Failure Data

This paper presents theory and applications of a simple graphical method, called hazard plotting, for the analysis of multiply censored life data consisting of failure times of failed units intermixed with running times on unfailed units. Applications of the method are given for multiply censored data on service life of equipment, for strength data on an item with different failure modes, and for biological data multiply censored on both sides from paired comparisons. Theory for the hazard plotting method, which is based on the hazard function of a distribution, is developed from the properties of order statistics from Type II multiply censored samples.

Theory and Applications of Hazard Plotting for Censored Failure Data

This paper presents theory and applications of a simple graphical method, called hazard plotting, for the analysis of multiply censored life data consisting of failure times of failed units intermixed with running times on unfailed units. Applications of the method are given for multiply censored data on service life of equipment, for strength data on an item with different failure modes, and for biological data multiply censored on both sides from paired comparisons. Theory for the hazard plotting method, which is based on the hazard function of a distribution, is developed from the properties of order statistics from Type II multiply censored samples.

The Thickogram: a method for easy film thickness measurement in XPS

We describe a simple graphical method for measuring film thickness by XPS, which we call Thickogram. This method incorporates the effects of elastic scattering and can be used even when the film and substrate peaks have very different kinetic energies (though it is still recommended that one use peaks as close as possible in genetic energy when there is an organic contamination layer over the film).

Stress Analyses in the Epicentral Area of Nový Kostel (Western Bohemia)

The focal mechanisms of events from three micro-earthquake swarms (swarm in the years 1985/86, swarm of December 1994, and swarm of January 1997) in the epicentral area of Nový Kostel (West Bohemia region) were used as input data for stress analyses. The simple graphical method of Angelier and Mechler (1977) and inversion by the program BRUTE3 (Hardcastle and Hills, 1993) were applied to the data collections. The results of the stress analyses for the 1985/86 swarm and for the swarm of December 1994 are similar. For the January 1997 swarm, the results of the analyses differ from those for older swarms. The axis of maximum extension is oriented in the NE-SW direction and is subhorizontal, the axis of maximum compression is oriented in the NW-SE direction and perspicuously dips towards SE. These results are similar to older results of stress analyses carried out for the 1985/86 swarm (Antonini, 1988; Sonnleitner,1993). They are also consistent with most of other published results of stress analyses conducted at different sites in the western part of the Bohemian Massif. The orientation of the principal stresses confirms the sinistral strike-slip movement along the Nový Kostel-Pocatky-Zwota line (the trend is about 355°) defined by the epicentres of the micro-earthquakes. The eastern tectonic limit of the Cheb Basin (and other respective parallel faults ) could be characterised by normal rather than strike-slip faulting.

Geochemistry of large river suspended sediments: silicate weathering or recycling tracer?

This study focuses on the major and trace element composition of suspended sediments transported by the world’s largest rivers. Its main purpose is to answer the following question: is the degree of weathering of modern river-borne particles consistent with the estimated river dissolved loads derived from silicate weathering? In agreement with the well known mobility of elements during weathering of continental rocks, we confirm that river sediments are systematically depleted in Na, K, Ba with respect to the Upper Continental Crust. For each of these mobile elements, a systematics of weathering indexes of river-borne solids is attempted. A global consistency is found between all these indexes. Important variations in weathering intensities exist. A clear dependence of weathering intensities with climate is observed for the rivers draining mostly lowlands. However, no global correlation exists between weathering intensities and climatic or relief parameters because the trend observed for lowlands is obscured by rivers draining orogenic zones. An inverse correlation between weathering intensities and suspended sediment concentrations is observed showing that the regions having the highest rates of physical denudation produce the least weathered sediments. Finally, chemical and physical weathering are compared through the use of a simple steady state model. We show that the weathering intensities of large river suspended sediments can only be reconciled with the (silicate-derived) dissolved load of rivers, by admitting that most of the continental rocks submitted to weathering in large river basins have already suffered previous weathering cycles. A simple graphical method is proposed for calculating the proportion of sedimentary recycling in large river basins. Finally, even if orogenic zones produce weakly weathered sediments, we emphasize the fact that silicate chemical weathering rates (and hence CO 2 consumption rates by silicate weathering) are greatly enhanced in mountains simply because the sediment yields in orogenic drainage basins are higher. Hence, the parameters that control chemical weathering rates would be those that control physical denudation rates.

Dimensionality of Scandinavian river flow regimes

A river flow regime describes an average seasonal behaviour of river flow, usually representing a set of long-term monthly mean values. Seasonal patterns of flow can be regular, repeating in principle the same pattern from year to year, or irregular, i.e. alternating between a couple of different regime types during individual years. By tradition, a river flow regime has been considered as a static characteristic that does not change in large temporal scale, yet this may be an oversimplification with regard to constantly changing environmental conditions. Such a “static” description of a flow regime, based on long-term mean values is in discrepancy with the dynamic character of the system described. The dimension of this system in terms of fractal and intrinsic dimensions has been investigated on an example of Scandinavian runoff series by different methods: from a simple graphic method to determine the fractal dimension to empirical orthogonal function (EOF) and entropy-based aggregation to outline the number of patterns necessary for representing the regimes of different intrinsic dimension of a set of point data. The series studied demonstrated a variety of fractal and intrinsic dimensions that were well in agreement with the stability character of the investigated regime types. The less stable the regime, the higher were its fractal and intrinsic dimensions and the number of variables required for its description.

Simplified graphical determination of disk-cam curvature

The equivalent four-bar linkage of a disk-cam mechanism can be constructed through the application of Freudenstein’s third theorem if the kinematic characteristics of the follower instead of the profile of the disk cam are specified. From such a process of reversing the usual construction order, the instantaneous radius of curvature of a disk-cam profile can be determined by means of the joint locations of the equivalent linkage. Based on this process, this paper presents a simple graphical method for determining the radius of curvature of a disk-cam profile. For most cases, the results obtained from this method are reasonably accurate.

A simple graphical method for the comparison of two mortality experiences

The potential of using differences in log crude mortality rates, matched age for age, as a simple means of comparing two mortality studies is investigated. Graphical displays of such differences, plotted against age, are advocated and a method of curve fitting described. A number of applications are presented, and the results of this approach compared with known results, where available. Copyright © 1999 John Wiley & Sons, Ltd.

Computing Displacements in Transversely Isotropic Rocks Using Influence Charts

This paper presents a simple graphical method for computing the displacement beneath/at the surface of a transversely isotropic half-space subjected to surface loads. The surface load can be distributed on an irregularly-shaped area. The planes of transverse isotropy are assumed to be parallel to the horizontal surface of the half-space. Based on the point load solutions presented by the authors, four influence charts are constructed for calculating the three displacements at any point in the interior of the half-space. Then, by setting z=0 of the derived solutions, another four influence charts for computing the surface displacements can also be proposed. These charts are composed of unit blocks. Each unit block is bounded by two adjacent radii and arcs, and contributes the same level of influence to the displacement. Following, a theoretical study was performed and the results showed that the charts for interior displacements are only suitable for transversely isotropic rocks with real roots of the characteristic equation; however, the charts for surface displacements are suitable for all transversely isotropic rocks. Finally, to demonstrate the use of the new graphical method, an illustrative example of a layered rock subjected to a uniform, normal circular-shaped load is given. The results from the new graphical method agree with those of analytical solutions as well. The new influence charts can be a practical alternative to the existing analytical or numerical solutions, and provide results with reasonable accuracy.

Determination of order parameters and correlation times in proteins: a comparison between Bayesian, Monte Carlo and simple graphical methods.

We describe a novel approach to deducing order parameters and correlation times in proteins using a Bayesian statistical method, and show how likelihood contours, P(tau,S), and confidence levels can be obtained. These results are then compared with those obtained from a simple graphical method, as well as those from Monte Carlo simulations. The Bayes approach has the advantage that it is simple and accurate. Unlike Monte Carlo methods, it gives useful contour plots of probability (also not provided by the simple graphical method), and provides likelihood/confidence information. In addition, the Bayesian approach gives results in very good agreement with those obtained from Monte Carlo simulations, and as such use of Bayesian statistical methods appears to have a promising future for studies of order and dynamics in macromolecules.

Hot-Mix Asphalt Volumetrics Revisited: A New Paradigm

As early as 1905, Richardson recognized the importance to performance of the relative proportions, by volume, of the material components of bituminous mixtures. In the 1940s, Marshall explicitly addressed the volumetric percentages of air voids and of the degree of void saturation by asphalt. In the late 1950s, McLeod clearly demonstrated and justified the appropriate aggregate specific gravities to be used in volumetric computations and emphasized the importance of the combined volumes of the air voids and effective asphalt binder. These various volumetric parameters have since formed a principal part of the Marshall design method and have more recently been enshrined into the Superpave system. The definitions of the various volumetric parameters and their interrelationships are revisited here. An instructive and useful chart has been developed with which mixtures of different volumetric characteristics may be compared and, through trajectory analysis, reduced to a common basis. A further simple graphical method has been developed that may be used to analyze, volumetrically, both Marshall and Superpave mix designs. The latter method can be used as a point-estimate method to identify the binder content that will yield any given air void content. Although no new technology is presented here, old information is presented in a new way—a new paradigm.

All the Bell inequalities

Bell inequalities are derived for any number of observers, any number of alternative setups for each one of them and any number of distinct outcomes for each experiment. It is shown that if a physical system consists of several distant subsystems, and if the results of tests performed on the latter are determined by local variables with objective values, then the joint probabilities for triggering any given set of distant detectors are convex combinations of a finite number of Boolean arrays, whose components are either 0 or 1 according to a simple rule. This convexity property is both necessary and sufficient for the existence of local objective variables. It leads to a simple graphical method which produces a large number of generalized Clauser-Horne inequalities corresponding to the faces of a convex polytope. It is plausible that quantum systems whose density matrix has a positive partial transposition satisfy all these inequalities, and therefore are compatible with local objective variables, even if their quantum properties are essentially non-local.

A graphical method for calculating the speech intelligibility index and measuring hearing disability from audiograms.

The speech intelligibility index (SII) is interpreted as the proportion of total speech information available to the listener's ear for a given speech material. Consequently, SII varies in the range 0-1. A simple graphical method for determining SII for monaural listening at 1 m distance from a talker producing "average speech" (or PB-words) at normal speech effort is described. The speech area is visualized by 10 x 10 = 100 points in the audiogram form, each point contributing 0.01 to the SII. The SII thus equals 0.01 times the number of points in the audible range. A sensorineural hearing loss gives rise to an additional loss in speech recognition due to reduced frequency discrimination and time resolving ability. This suprathreshold deficit is corrected for, if the SII contribution in each frequency band is multiplied with a hearing threshold level dependent "desensitization factor". The SII is related to the intelligibility of speech, and may be used to evaluate a hearing disability.

News analytical reagents for europium(III)

The complexant reactions of 2′-hydroxychalcones with europium(III) are studied by the spectrophotometric method. The apparent formation constants are evaluated using a simple graphical linear method. The sequence of these constant values is explained and compared with aluminium(III) complexant reactions.

A simple graphical method for displaying multiple dimensions by group over time: An example using the SF-36

A simple graphical method for displaying multiple dimensions by group over time: An example using the SF-36

Overdispersion: Models and estimation

Overdispersion models for discrete data are considered and placed in a general framework. A distinction is made between completely specified models and those with only a mean-variance specification. Different formulations for the overdispersion mechanism can lead to different variance functions which can be placed within a general family. In addition, many different estimation methods have been proposed, including maximum likelihood, moment methods, extended quasi-likelihood, pseudo-likelihood and non-parametric maximum likelihood. We explore the relationships between these methods and examine their application to a number of standard examples for count and proportion data. A simple graphical method using half-normal plots is used to examine different overdispersion models.

094009 (M21) A simple graphical method for the comparison of two mortality experiences : Renshaw A.E., Haberman S.,Actuarial Research Paper N o96, Department of Actuarial Science and Statistics, City University, UK, 1997

094009 (M21) A simple graphical method for the comparison of two mortality experiences : Renshaw A.E., Haberman S.,Actuarial Research Paper N o96, Department of Actuarial Science and Statistics, City University, UK, 1997

Considerations for calculating heat inactivation processes when semilogarithmic thermal inactivation models are non-linear

Bigelow's method is the basis of all modern thermal process calculations. These calculations are based on the assumption that the heat inactivation model follows first order kinetics. However, as demonstrated in this paper, Bigelow's method is applicable in all cases when the heat inactivation process can be characterized by a relation of three variables: t{T,N} = g{T} · f{N} where t = heat treatment time at constant temperature T; T = temperature; and N = number of surviving micro-organisms at time t. The function g{T} depends only on T and f{N} is another function depending only on N. As shown in this paper, the (classic) empirical kinetic equation satisfies this requirement, however, several non-linear semilogarithmic microbial heat inactivation models do not conform to the above relationship. In dubious cases, when proper equations for experimentally determined heat inactivation curves are uncertain or unknown, a simple graphical method is proposed to assess whether these curves correspond to a g{T} · f{N} type function.

A graphical method for determining the dry-depositional component of aerosol samples and their field blanks

During the Atmosphere/Ocean Chemistry Experiment (AEROCE), field blanks of certain elements in aerosol samples occasionally increased abruptly, always during periods of unusually high atmospheric concentrations. We hypothesized that the anomalous blanks were created by coarse aerosol entering the sampling shelters and depositing onto the blank filters. If so, samples taken nearby should have been similarly affected. To test this hypothesis, we developed a simple graphical method in which elemental masses in field blanks are plotted against elemental masses in pumped samples, and zones of proportionality between the two are sought. Data from Bermuda and Mace Head (coastal western Ireland) confirmed that depositional zones did indeed appear, but only for coarse-particle elements and only under certain conditions. Actual increases of crustal and pollution-derived elements agreed well with values predicted from settling velocities and sampling rates: blanks increased up to an order of magnitude or more but samples by less than 1%. Marine elements behaved like crustal elements in most samples but occasionally were much more enriched: blanks increased up to 30-fold and samples up to about 3%. It thus appears that when coarse-particle elements are present in high concentrations, their field blanks and samples may be measurably affected by dry deposition. Depending on the elements of interest, this dry deposition may have to be measured and the concentrations corrected.