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The purpose of this paper is to report new original evidence on optimal holding periods and optimal asset allocations (Benartzi and Thaler, 1995).

The authors employ a number of different value functions, a recent dataset, different markets, and varying investment horizons.

The authors report original evidence across markets and over-time, employing different value functions and varying investment horizons. The results results indicate that, during the past decades, the optimal holding period (seven months during the whole period and four/five months during crises) is not affected by the value function employed, is in accordance with the Myopic Loss Aversion hypothesis, is consistent across markets, but is sensitive to economic crises and shorter to that reported in Benartzi and Thaler (12 months). The optimal asset allocation is also different to that of Benartzi and Thaler during crises periods and/or assuming value functions with probability distortion.

The paper employs a number of different value functions, with and without probability distortion; it compares investor behavior in three important international markets (USA, UK, Germany); as a further robustness test the authors use various investment horizons.

Mesh Parameterization is central to reverse engineering, tool path planning, etc. This work synthesizes parameterizations with un-constrained borders, overall minimum angle plus area distortion. This study aims to present an assessment of the sensitivity of the minimized distortion with respect to weighed area and angle distortions.

A Mesh Parameterization which does not constrain borders is implemented by performing: isometry maps for each triangle to the plane Z = 0; an affine transform within the plane Z = 0 to glue the triangles back together; and a Levenberg–Marquardt minimization algorithm of a nonlinear F penalty function that modifies the parameters of the first two transformations to discourage triangle flips, angle or area distortions. F is a convex weighed combination of area distortion (weight: α with 0 ≤ α ≤ 1) and angle distortion (weight: 1 − α).

The present study parameterization algorithm has linear complexity [𝒪(n), n = number of mesh vertices]. The sensitivity analysis permits a fine-tuning of the weight parameter which achieves overall bijective parameterizations in the studied cases. No theoretical guarantee is given in this manuscript for the bijectivity. This algorithm has equal or superior performance compared with the ABF, LSCM and ARAP algorithms for the Ball, Cow and Gargoyle data sets. Additional correct results of this algorithm alone are presented for the Foot, Fandisk and Sliced-Glove data sets.

The devised free boundary nonlinear Mesh Parameterization method does not require a valid initial parameterization and produces locally bijective parameterizations in all of our tests. A formal sensitivity analysis shows that the resulting parameterization is more stable, i.e. the UV mapping changes very little when the algorithm tries to preserve angles than when it tries to preserve areas. The algorithm presented in this study belongs to the class that parameterizes meshes with holes. This study presents the results of a complexity analysis comparing the present study algorithm with 12 competing ones.

It is shown that the widely used risk measures standard deviation and value at risk do not always reflect risk preferences accurately. To overcome these problems in risk measurement a class of coherent risk measures has been proposed. We introduce the idea behind these measures and provide an overview of suggested coherent risk measures. Finally it is shown where the limitations of such measures in practical applications are and how regulatory bodies responded to their introduction in the literature. We find that most contributions on coherent risk measurement come from the actuarial sciences and propagate a widening of the discussion among researchers and practitioners in other industries.

The Rate Distortion Theory is a branch of the Information Theory applicable to the case when the entropy of the source exceeds the capacity of the Channel. A rate distortion function R(D) is defined between the input and output alphabets X, Y of a channel. It can be shown that it is possible to design a communication system which achieves a fidelity D when the capacity of the channel C is greater than R(D). In this paper, the formulation of the Rate Distortion Theory is used for the problem of derived probability models. The variables X, Y and the Channel are given new interpretations, and the result is an ability to pick a derived probability model for Y when X is of a known probability structure. The fidelity criterion assumes the rle of an error function in this terminology. Two specific cases are discussed.

The purpose of this paper is to introduce a new probability density function having both unbounded and bounded support with a wider applicability. While the distribution with bounded support on [0, 1] has applications in insurance and inventory management with ability to fit risk management data on proportions better than existing bounded distributions, the same with unbounded support is used as a lifetime model and is considered as an attractive alternative to some existing models in the reliability literature.

The new density function, called modified exponential-geometric distribution is derived from the exponential-geometric distribution introduced by Adamidis and Loukas (1998). The support of the density function is shown to be both unbounded and bounded depending on the values of one of the shape parameters. Various properties of the density function are studied in detail and the parameters are estimated through maximum likelihood method of estimation. A number of applications related to reliability, insurance and inventory management are exhibited along with some useful data analysis.

A single probability distribution with both unbounded and bounded support, which does not seem to exist in the reliability literature, is introduced in this paper. The proposed density function exhibits varying shapes including U-shape, and the failure rate also shows increasing, decreasing and bathtub shapes. The Monte Carlo simulation shows that the estimates of the parameters are quite stable with low standard errors. The distribution with unbounded support is shown to have competitive features for lifetime modeling through analysis of two data sets. The distribution with bounded support on [0, 1] is shown to have application in insurance and inventory management and is found to t data on proportions related to risk management better than some existing bounded distributions.

The authors introduce an innovative probability distribution which contributes significantly in insurance and inventory management besides its remarkable statistical and reliability properties.

The purpose of this paper is to give a review on the newest developments of high-performance finite element methods (FEMs), and exhibit the recent contributions achieved by the authors’ group, especially showing some breakthroughs against inherent difficulties existing in the traditional FEM for a long time.

Three kinds of new FEMs are emphasized and introduced, including the hybrid stress-function element method, the hybrid displacement-function element method for Mindlin–Reissner plate and the improved unsymmetric FEM. The distinguished feature of these three methods is that they all apply the fundamental analytical solutions of elasticity expressed in different coordinates as their trial functions.

The new FEMs show advantages from both analytical and numerical approaches. All the models exhibit outstanding capacity for resisting various severe mesh distortions, and even perform well when other models cannot work. Some difficulties in the history of FEM are also broken through, such as the limitations defined by MacNeal’s theorem and the edge-effect problems of Mindlin–Reissner plate.

These contributions possess high value for solving the difficulties in engineering computations, and promote the progress of FEM.

The purpose of this paper is to develop a numerical approach inspired by Geometrical Product Specifications (GPS) standards for the assessment of geometrical defects appearing during Additive Manufacturing (AM) by Laser Beam Melting (LBM).

The study is based on finite element (FE) simulations of thermal distortions, then an assessment of flatness defects (warping induced by the high-residual stresses appearing during the manufacturing) from the deformed surfaces provided by simulation, and finally the correction of the calculated flatness defects from preliminary comparison between simulated and experimental data.

For an elementary geometrical feature (a wall), it was possible to identify the variation in the flatness defect as a function of the dimensions. For a complex geometry exhibiting a significant flatness defect, it was possible to improve the geometric quality using the numerical tool.

To the best of the author’s knowledge, this work is the first attempt using a numerical approach inspired by GPS standards to identify variations in thermal distortions caused by LBM, which is an initial step toward optimization. This paper is mainly focused on flatness defect assessment, even though the approach is potentially applicable for all types of geometrical defects (shape, orientation or position defects).

The study opens prospects for the optimization of complex parts elaborated using LBM, based on the minimization of the geometric defects caused by thermal distortions.

The prospects in terms of shape optimization will extend the potential to benefit from the new possibilities offered by LBM additive manufacturing.

Unlike the usual approach, the proposed methodology does not require any artifacts or comparisons with the computer-aided-design (CAD) model for geometrical distortion assessment. The present approach opens up the possibility of performing metrology from FE simulation results, which is particularly promising in the AM field.

Accurate alignment is vital to acquire high‐quality joints with less negative effects on the rest parts of the chip or other components on a board. The purpose of this paper is to develop an integrated laser soldering system, which is accurate, compact, and flexible.

The system combines an X‐Y stage, a computer vision module and a laser module. It would automatically sense the soldering pads with computer vision, fulfill the alignment of laser beam and soldering pads together with the motion system, and finish the soldering work with laser power.

Based on the analysis of experimental data, it is found that lens distortion and assembly angular errors of the X‐Y stage play a distinct role on the alignment errors.

The paper proposes an algorithm based on straight line method to reduce image distortion, and a compensation algorithm on the angular errors of the X‐Y positioning stage. Experimental results show that the overall precision is satisfied for fine pitch applications and the system performs well.

Although it has been proved theoretically that annuities can provide optimal consumption during one’s retirement period, retirees’ reluctance to purchase annuities is a long-standing puzzle. The purpose of this paper is to use behavioral model to analyze the low demand for immediate annuities.

The authors employ cumulative prospect theory (CPT), which contains both loss aversion and probability transformations, to analyze the annuity puzzle.

The authors show that CPT can explain the unattractiveness of immediate annuities. It also shows that retirees would be willing to buy a long-term deferred annuity at retirement. By considering each component from CPT in turn, the loss aversion is found to be the major reason that stops people from buying an annuity while the survival rate transformation is an important factor affecting the decision of when to receive annuity incomes.

This paper identifies CPT as one of the reasons for the low demand of immediate annuities. It further suggests that long-term deferred annuities could overcome behavioral obstacles and become popular among retirees.

The purpose of this paper is to extend a recent unsymmetric 8-node, 24-DOF hexahedral solid element US-ATFH8 with high distortion tolerance, which uses the analytical solutions of linear elasticity governing equations as the trial functions (analytical trial function) to geometrically nonlinear analysis.

Based on the assumption that these analytical trial functions can still properly work in each increment step during the nonlinear analysis, the present work concentrates on the construction of incremental nonlinear formulations of the unsymmetric element US-ATFH8 through two different ways: the general updated Lagrangian (UL) approach and the incremental co-rotational (CR) approach. The key innovation is how to update the stresses containing the linear analytical trial functions.

Several numerical examples for 3D structures show that both resulting nonlinear elements, US-ATFH8-UL and US-ATFH8-CR, perform very well, no matter whether regular or distorted coarse mesh is used, and exhibit much better performances than those conventional symmetric nonlinear solid elements.

The success of the extension of element US-ATFH8 to geometrically nonlinear analysis again shows the merits of the unsymmetric finite element method with analytical trial functions, although these functions are the analytical solutions of linear elasticity governing equations.