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One of the crucial issues in the contemporary finance is the prediction of the volatility of financial assets. In this paper, the authors are interested in modelling the stochastic volatility of the MAD/EURO and MAD/USD exchange rates.

For this purpose, the authors have adopted Bayesian approach based on the MCMC (Monte Carlo Markov Chain) algorithm which permits to reproduce the main stylized empirical facts of the assets studied. The data used in this study are the daily historical series of MAD/EURO and MAD/USD exchange rates covering the period from February 2, 2000, to March 3, 2017, which represent 4,456 observations.

By the aid of this approach, the authors were able to estimate all the random parameters of the stochastic volatility model which permit the prediction of the future exchange rates. The authors also have simulated the histograms, the posterior densities as well as the cumulative averages of the model parameters. The predictive efficiency of the stochastic volatility model for Morocco is capable to facilitate the management of the exchange rate in more flexible exchange regime to ensure better targeting of monetary and exchange policies.

To the best of the authors’ knowledge, the novelty of the paper lies in the production of a tool for predicting the evolution of the Moroccan exchange rate and also the design of a tool for the monetary authorities who are today in a proactive conception of management of the rate of exchange. Cyclical policies such as monetary policy and exchange rate policy will introduce this type of modelling into the decision-making process to achieve a better stabilization of the macroeconomic and financial framework.

This paper aims to reconstruct the spatially varying orthotropic conductivity based on a two-dimensional inverse heat conduction problem described by a partial differential equation (PDE) model with mixed boundary conditions. The proposed discretization uses a highly accurate technique and allows simple implementations. Also, the authors solve the related inverse problem in such a way that smoothness is enforced on the iterations, showing promising results in synthetic examples and real problems with moving heat source.

The discretization procedure applied to the model for the direct problem uses a pseudospectral collocation strategy in the spatial variables and Crank–Nicolson method for the time-dependent variable. Then, the related inverse problem of recovering the conductivity from temperature measurements is solved by a modified version of Levenberg–Marquardt method (LMM) which uses singular scaling matrices. Problems where data availability is limited are also considered, motivated by a face milling operation problem. Numerical examples are presented to indicate the accuracy and efficiency of the proposed method.

The paper presents a discretization for the PDEs model aiming on simple implementations and numerical performance. The modified version of LMM introduced using singular scaling matrices shows the capabilities on recovering quantities with precision at a low number of iterations. Numerical results showed good fit between exact and approximate solutions for synthetic noisy data and quite acceptable inverse solutions when experimental data are inverted.

The paper is significant because of the pseudospectral approach, known for its high precision and easy implementation, and usage of singular regularization matrices on LMM iterations, unlike classic implementations of the method, impacting positively on the reconstruction process.

The purpose of this paper is to identify if peer firms’ capital structure decision plays a role in determining focal firms’ capital structure decision, despite the fact that correlated effects can also lead to co-movement of financing behavior among firms from the same industry (i.e. industry-specific capital structure).

Instead of using relative measurement (of individual outcome variable over industry variable) as in previous work, this paper borrows the linear-in-means model and, after controlling for potential endogeneity problems, directly identifies the existence of peer effects with coefficient estimation. To deal with correlated effects, additional empirical investigations such as test of heterogeneity in direction and scale, social multiplier identification test and instrumental regression test based on another instrumental variable (that is less influenced by correlated effects) are performed.

Using data from Chinese listed firms, this paper, for the first time, identifies the presence of peer effects in capital structure and debt maturity decision. Further investigations show that first, focal firms react asymmetrically to peer firms’ debt adjustment of different direction and scale. Second, social multiplier, a unique attribute of peer effects, is identified in the leverage choices. Third, the significant correlation of capital structure decision remains even if we use another “correlated effects-immune” instrument. All these results point to the fact that peer effects, rather than correlated effects, play a significant role in determining capital structure.

The empirical results of this paper provide strong evidence that firms, driven by motivations such as either learning or competition, will actively react to peers’ financial decisions. As the bridge between individual firms and the industry, social multiplier can be fully taken advantage of to induce positive spillover of good management practices and prohibit inefficient decisions from spreading.

This paper theoretically and empirically introduces peer effects – a well-acknowledged social concept – into capital structure decision of Chinese listed firms, thus both complementing the traditional capital structure theory and providing an empirical paradigm for peer effects research.

The purpose of this paper is to further the scholarly discussion of information experience as an object of study, including how this research area fits into library and information studies more broadly.

A conceptual discussion of certain issues raised in Yu and Liu's recent paper in this journal.

While Yu and Liu seem to suggest that only a priori information experience research belong in library and information science (LIS), this paper suggests that a priori and a posteriori research have a synergistic relationship and both have a home in LIS.

This paper clarifies how the two conceptualizations of information experience as an object of study relate to each other, as well as how these relate to information experience as a research approach, and how all this fits within the metadisciplinary field of LIS.

The segmentation of printed circuit board (PCB) images is an important process in PCB inspection. The circuit traces, pads and vias in a PCB are dense and curved, and the PCB image obtained using different cameras or in different conditions may exhibit a large image gradient, which leads to inaccuracy and inefficiency in the PCB image segmentation. This paper aims to propose an improved local binary fitting level set method with prior graph cut, aiming to improve the accuracy and efficiency of the segmentation of PCB images obtained using different cameras or in different environments.

First, the paper constructs a 4-connected undirected graph using a given PCB image and classifies it based on the graph cut. Second, an adaptive initialization level set is implemented using the priori information obtained from the graph cut. Finally, the paper constructs a priori energy term using the prior information and introduces it into the energy function of the level set.

The approach results in an improved accuracy of segmentation in the context of a large gradient within the image. Experimental results demonstrate that the method can solve the deviation of artificially initialized level set from targets and improve the efficiency and accuracy of segmentation.

This study only considers level set method as the research object. Iteration of the level set method takes a long time for a given huge PCB picture, which makes it impossible to apply to scenes with high real-time requirements.

PCB image segmentation is an important process in the PCB inspection. Since template matching and morphology techniques are well-established, image segmentation quality has a significant impact on the accuracy of detection.

This paper studies the segmentation of PCB images, improves the efficiency and accuracy of segmentation and facilitates the subsequent applications, such as in the nondestructive testing of PCB.

This study aims to contribute to the clarification of core concepts in information experience research and to the consolidation of information experience as a distinctive research object.

This study adopts a series of techniques from Wilson's toolkit of concept analysis.

This study finds that there exist tensions between different uses of the term information experience, giving rise to two fundamentally different conceptions of this particular human experience which this study names, respectively, the posterior conception and the a priori conception. It also finds that it is linguistically more useful, practically more consonant with LIS's concerns and unitarily more consistent to define information experience following the a priori conception. It postulates that information experience can be defined as a person's subjective, pre-reflective living through of his/her life as an information user in the information sphere of the lifeworld.

If adopted by future research, the concept proposed in this study is likely to push information experience research toward a more prominent phenomenological turn on the one hand, and a return to conventional LIS concerns on the other.

The clarified concept may help user experience librarians and system designers to see the relevance of information experience research for their work more clearly.

By identifying, comparing and discussing different existing uses of information experience, and by suggesting a redefinition of the concept, this study has brought the core concepts of information experience research to a new level of clarity, and has verified information experience as a distinctive object for LIS research.

The purpose of this paper is to propose a new computational approach for parameter estimation in the Bayesian framework. A posteriori probability density functions are obtained using the polynomial chaos theory for propagating uncertainties through system dynamics. The new method has the advantage of being able to deal with large parametric uncertainties, non‐Gaussian probability densities and nonlinear dynamics.

The maximum likelihood estimates are obtained by minimizing a cost function derived from the Bayesian theorem. Direct stochastic collocation is used as a less computationally expensive alternative to the traditional Galerkin approach to propagate the uncertainties through the system in the polynomial chaos framework.

The new approach is explained and is applied to very simple mechanical systems in order to illustrate how the Bayesian cost function can be affected by the noise level in the measurements, by undersampling, non‐identifiablily of the system, non‐observability and by excitation signals that are not rich enough. When the system is non‐identifiable and an a priori knowledge of the parameter uncertainties is available, regularization techniques can still yield most likely values among the possible combinations of uncertain parameters resulting in the same time responses than the ones observed.

The polynomial chaos method has been shown to be considerably more efficient than Monte Carlo in the simulation of systems with a small number of uncertain parameters. This is believed to be the first time the polynomial chaos theory has been applied to Bayesian estimation.

This paper aims to propose a series of approaches to solve the problem of the mobile robot motion control and autonomous navigation in large-scale outdoor GPS-denied environments.

Based on the model of mobile robot with two driving wheels, a controller is designed and tested in obstacle-cluttered scenes in this paper. By using the priori “topology-geometry” map constructed based on the odometer data and the online matching algorithm of 3D-laser scanning points, a novel approach of outdoor localization with 3D-laser scanner is proposed to solve the problem of poor localization accuracy in GPS-denied environments. A path planning strategy based on geometric feature analysis and priority evaluation algorithm is also adopted to ensure the safety and reliability of mobile robot’s autonomous navigation and control.

A series of experiments are conducted with a self-designed mobile robot platform in large-scale outdoor environments, and the experimental results show the validity and effectiveness of the proposed approach.

The problem of motion control for a differential drive mobile robot is investigated in this paper first. At the same time, a novel approach of outdoor localization with 3D-laser scanner is proposed to solve the problem of poor localization accuracy in GPS-denied environments. A path planning strategy based on geometric feature analysis and priority evaluation algorithm is also adopted to ensure the safety and reliability of mobile robot’s autonomous navigation and control.

Information seeking does not occur in a vacuum but invariably is motivated by some wider task. It is well accepted that to understand information seeking we must understand the task context within which it takes place. Writing is amongst the most common tasks within which information seeking is embedded. This paper considers how writing can be understood in order to account for embedded information seeking. Following Sharples, the paper treats writing as a design activity and explore parallels between the psychology of design and information seeking. Significant parallels can be found and ideas from the psychology of design offer explanations for a number of information seeking phenomena. Next, a design‐oriented representation of writing tasks as a means of providing an account of phenomena such as information seeking uncertainty and focus refinement is developed. The paper illustrates the representation with scenarios describing the work of newspaper journalists.