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This paper aims to examine the valuation precision of composite models in each of six key industries in South Africa. The objective is to ascertain whether equity-based composite multiples models produce more accurate equity valuations than optimal equity-based, single-factor multiples models.

This study applied principal component regression and various mathematical optimisation methods to test the valuation precision of equity-based composite multiples models vis-à-vis equity-based, single-factor multiples models.

The findings confirmed that equity-based composite multiples models consistently produced valuations that were substantially more accurate than those of single-factor multiples models for the period between 2001 and 2010. The research results indicated that composite models produced up to 67 per cent more accurate valuations than single-factor multiples models for the period between 2001 and 2010, which represents a substantial gain in valuation precision.

The evidence, therefore, suggests that equity-based composite modelling may offer substantial gains in valuation precision over single-factor multiples modelling.

In light of the fact that analysts’ reports typically contain various different multiples, it seems prudent to consider the inclusion of composite models as a more accurate alternative.

This study adds to the existing body of knowledge on the multiples-based approach to equity valuations by presenting composite modelling as a more accurate alternative to the conventional single-factor, multiples-based modelling approach.

With the widespread use of the composites over other metallic materials in different fields of engineering, studies on damages of composite structures have assumed great importance. Among various kinds of damages, delamination is of very serious concern to composite applications. It may arise as a consequence of impact loading, stress concentration near a geometrical or material discontinuity or manufacturing defects. The presence of one or more delaminations in the composite laminate may lead to a premature collapse of the structure due to buckling at a lower level of compressive loading. So the effect of delamination on stability of composite structures needs attention and thus constitutes a problem of current interest. The purpose of this paper is to deal with both numerical and experimental investigations on buckling behaviour of single and multiple, delaminated, industry driven, woven roving glass/epoxy composite plates on clamped free clamped free (CFCF) rectangular plates.

For numerical analysis, a finite element model was developed with an eight noded two dimensional quadratic isoparametric element having five degrees of freedom per node. The elastic stiffness matrices were derived using linear first order shear deformation theory with a shear correction factor. Green's nonlinear strain equations are used to derive the geometric stiffness matrix. The computation of buckling load based on present formulation is compared with the experimental results for the effect of different parameters on critical load of the delaminated composite panels. In the experimental study, the influences of various parameters such as delamination area, fiber orientations, number of layers, aspect ratios on the buckling behaviour of single and multiple delaminated woven roving glass/epoxy composite plates were investigated. Buckling loads were measured by INSTRON 1195 machine for the delaminated composite plates.

Comparison of numerical results with experimental results showed a good agreement. Both the results revealed that the area of delaminations, fiber orientations, number of layers and aspect ratio have paramount influence on the buckling behaviour of delaminated plate.

The present study is part of Jayaram Mohanty's doctoral thesis, an original research work.

The present paper deals with the finite element dynamic analysis of delaminated composite twisted plates based on a simple multiple delaminated model. Eight‐noded isoparametric quadratic elements are used to develop the finite element analysis procedure. Composite plates are assumed to contain both single and multiple delaminations. To investigate the dynamic behaviour of delaminated twisted plates, numerical results for free vibration, forced vibration and impact response are generated by varying the size and location of delaminations as well as the stacking sequence and other geometrical parameters.

The introduction of a three-quarter-view database in the PRO-fit facial-composite system has enabled an investigation into the effects of image view in face construction. The purpose of this paper is to examine the impact of constructing full-face and three-quarter-view composites under different encoding conditions. It also examines the potential value of three-quarter-view composites that can be generated automatically from a front-view composite. The authors also investigate whether there is an identification benefit for presenting full-face and three-quarter composites together.

Three experiments examine the impact of encoding conditions on composite construction and presentation of composites at the evaluation stage.

The work revealed that while standard full-face composites perform well when all views of the face have been encoded, care should be taken when a person has only seen one view. When a witness has seen a side view of a suspect, a three-quarter-view composite should be constructed. Also, it would be beneficial for a witness to construct two composites of a suspect, one in full-face view and one in a three-quarter-view, particularly when the witness has only encoded one view. No benefit emerged for use of three-quarter-view composites generated automatically.

This is the first study to examine viewpoint in facial composite construction. While a great deal of research has examined viewpoint dependency in face recognition tasks, composite construction is a reconstruction task involving both recall and recognition. The results indicate that there is a viewpoint effect that is similar to that described in the recognition literature. However, more research is needed in this area.

The practical implications of this research are that it is extremely important for facial composite operators in the field (police operators) to know who will make a good likeness of the target. Research such as this which examines real-life issues is incredibly important. This research shows that if a witness has seen all views of a perpetrator’s face then standard composite construction using a full-face view will work well. However, if they have only seen a single view then it will not.

There are obvious wider societal implications for any research which deals with eyewitness memory and the potential identification of perpetrators.

No research to date has formally examined the impact of viewpoint in facial-composite construction.

The purpose of this paper is to study the nonlinear forced vibration responses of delaminated composite shells in hygrothermal environments.

Finite element method using an eight-noded C0 continuity, isoparametric quadrilateral element is employed. The theoretical formulations are based on the first order shear deformation theory and von Kármán type nonlinear kinematics. For modeling the delamination, multipoint constraint algorithm is incorporated in the finite element code.

The effect of delaminations on the nonlinear transient response of delaminated composite shells is dependent not only on the size but also on the location of the delaminations and hygrothermal environments.

The present study is limited to cylindrical and spherical shells having rectangular planform containing single delamination. Studies on different shell forms having non rectangular planforms containing multiple delaminations can be taken up for future research.

Nonlinear transient response of delaminated shells in hygrothermal environments is studied for the first time. It will assist researchers of nonlinear dynamic behavior of elastic systems.

The purpose of this paper is to study the nonlinear forced vibration response of delaminated composite shells in hygrothermal environments.

Finite element method using an eight‐noded C⁰ continuity, isoparametric quadrilateral element is employed. The theoretical formulations are based on the first‐order shear deformation theory and von Kármán type nonlinear kinematics. For modeling the delamination, multipoint constraint algorithm is incorporated in the finite element code.

The paper finds that the effect of presence of delaminations on the nonlinear transient response of composite shells is dependent not only on the size, but also on the location of the delaminations and the hygrothermal environments.

The present study is limited to cylindrical and spherical shells having rectangular planform containing single delamination. Studies on different shell forms having non‐rectangular planforms containing multiple delaminations can be taken up for future research.

The value in this paper lies in that nonlinear transient response of delaminated shells in hygrothermal environments is studied for the first time. It will assist researchers of nonlinear dynamic behavior of elastic systems.

We explore the effects of three categories of fit on US‐China joint‐venture performance using four performance measures. Many studies prescribe strong fit across multiple categories as necessary for high performance, but little rigorous analysis supports this. Three important threads of existing “fit” research resonate in the literature: strategic, cultural and organizational fit. We analyze an original survey dataset of over 80 US‐China JVs, and test for effects of fit‐categories using two measures for each thread. Additionally, multiple control factors give a compelling look at a complete model of fit’s effects on JV performance. Objective congruence (strategic fit) among JV partner‐firms, impacts two performance‐measures. Efficacy of managerial communications (cultural fit) also matters, as does harmony regarding hiring decisions (organizational fit). Our findings are a step forward empirically, and partly resolve persistent questions about partner‐fit in JVs and performance.

It is well‐known that clean room textiles are acting as a barrier protecting humans against the surrounding atmosphere or vice versa. These textiles are produced in the limited range of porosity and the air permeability. The porosity calculated from fabric geometry and the air permeability of two typical clean room textiles of Czech production are measured. The variation of air permeability is described by the analysis based on the coefficient of variation and spatial autocorrelation. The air permeability of composite textiles of multiple layers is predicted from a simple model. This model is based on the idea of a combination of air pressure drop in individual layers. The predicted air permeability is compared with experimental measurements.

This paper aims to focus on calculating the number of layers of composite laminates required to take the applied load made up of graphite/epoxy (AS4/3501-6) which can be used in many industrial applications. Optimization for minimization of weight by variation in the mechanical properties is possible by using different combinations of fiber angle, number of plies and their stacking sequence.

Lots of research studies have been put forth by aerospace industry experts to improve the performance of aircraft wings with weight constraints. The orthotropic nature of the laminated composites and their ability to characterize as per various performance requirements of aerospace industry make them the most suitable material. This leads to necessity of implementing most appropriate optimization technique for selecting appropriate parameter sets and material configurations.

In this work, exhaustive enumeration algorithm has been applied for weight minimization of fiber laminated composite beam subjected to two different loading conditions by computing overall possible stacking sequences and material properties using classical laminate theory. This combinatorial type optimization technique enumerates all possible solutions with an assurance of getting global optimum solution. Stacking sequences are filtered through Tsai-Wu failure criteria.

Finally, through the outcome of this optimization framework, eight different combinations of stacking sequences and 24-ply symmetric layup have been obtained. Furthermore, this 24-ply layup weighing 0.468 kg has been validated using finite element solver for given boundary conditions. Interlaminar stresses at top and bottom of the optimized ply layup were validated with Autodesk’s Helius composites solver.

This paper gives a review of the finite element techniques (FE) applied in the analysis and design of machine elements; bolts and screws, belts and chains, springs and dampers, brakes, gears, bearings, gaskets and seals are handled. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of this paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An Appendix included at the end of the paper presents a bibliography on finite element applications in the analysis/design of machine elements for 1977‐1997.