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The purpose of this paper is to propose a new inspecting algorithm for defect detection on PCB circuits.

PCB circuit images were processed by a radon transformation. A Radon histogram was formed and utilized to establish a texture directional characteristic similarity function. Then, a region of the image which contained the same texture directionality feature was segmented. Furthermore, a directionality estimation method is presented. As the circuit was damaged, the directionality was weakened correspondingly. According to principle, the concept of directional intensity was proposed and then used to measure directionality through analysis of the Radon histogram fluctuation. Finally, the defect was detected based on directional intensity.

The method has been applied to an inspecting system used in practice and it achieved a higher accuracy and efficiency in comparison with similar methods.

Although work on highly intensive PCB circuitry inspection and flaw detection is presented, defect classification was not involved although this is also a very important requirement of inspection.

The paper provides a new way to detect PCB circuitry defects based on texture directionality and proposes evaluating the similarity between image texture directionalities using a radon transformation to search the inspected area. As the inspected region was located, the concept of directional intensity was defined to measure texture directionality to identify defects. The new algorithm performs stably and efficiently and is fit for practical application.

This paper aims to develop a numerical model to investigate coupled conduction radiation heat transfer in a multilayer semi-transparent polymeric foam.

The model uses a multi-phase approach in which the radiative transfer is determined by solving the radiative transfer equation explicitly in the whole medium incorporating an interface condition valid in the geometric optics rgime. This is executed by using a combination of ray splitting and a discrete curved ray tracing technique. Both partial photon reflection and total internal reflection at the interface are considered in the present investigation.

The directional distribution of intensity within the whole medium can be determined, which is used to obtain the detailed temperature profile inside the domain. The performance of the proposed methodology has been tested by simulating the modelled foam at ambient conditions. The results obtained from the simulations are in good agreement with the published results and shows that there is a global non-linearity in the temperature profile in problems where conduction to radiation parameter is small.

Specular nature of radiative transfer at the interface is accounted for in the present analysis. Instead of working with direction integrated quantities (as in the case of P1 approximation), each bundle of rays is treated separately within the whole medium. This model serves as a starting point for a detailed spatially three dimensional study of heat transfer in foams and the mathematical nature of the formulation is such that it may result in an implementation to three-dimensions.

The current study aims to address the interaction between participating media radiation with thermo-gravitational convection of an electrically conducting fluid enclosed within a tilted enclosure under an externally imposed time-independent uniform magnetic field.

The differentially heated boundaries of the tilted enclosure are considered to be diffuse, gray and the enclosed fluid is assumed to be absorbing, emitting and isotropically scattering. The Navier-Stokes equations, meant for magneto convection are solved using modified MAC method. Gradient dependent consistent hybrid upwind scheme of second order is used for discretization of the convective terms. Discrete ordinate method, with S8 approximation, is used to model radiative transport equation in the presence of radiatively active medium.

Effect of uniform magnetic field with different magnitudes and orientations of cavity has been numerically simulated. The effect of participating media radiation has been investigated for different optical thicknesses, emissivities, scattering albedos and Planks number. The results are provided in both graphical and tabular forms. The flow lines, isotherms bring clarity in the understanding of flow behaviour and heat transfer characteristics.

Despite the idealized nature, the present study is quite essential to understand the cumbersome physics of realistic problem.

The paper aims to test the spectral line-based weighted sum of gray gases (SLW) method in axisymmetric geometries with particles and high temperature gradients.

An SLW model is coupled with Trivic’s mean wavelength approach to estimate the radiative heat fluxes at the wall of an enclosure and to the base wall of the rocket exhaust, thereby subsequently studying the effect of concentration variation of the gases and particles in these cases. Radiative transfer equation is solved using modified discrete ordinates method. Anisotropic scattering is modeled using transport approximation.

Two cases considered show the importance of particle emission and scattering in the rocket plume base heating problems. In cases involving only gases, the concentration of H₂O tends to have more impact on the flux values than any other gas.

A full model of gases with particles in an axially varying temperature field is reported. Such cases are very common in practical applications. The present methodology gives more insight and a firm handle on the problem vis-a-vis other traditional techniques.

A finite element method for the analysis of combined radiative and conductive heat transport in a finite axisymmetric configuration is presented. The appropriate integro‐differential governing equations for a grey and non‐scattering medium with grey and diffuse walls are developed and solved for several model problems. We consider axisymmetric, cylindrical geometries with top and bottom boundaries of arbitrary convex shape. The method is accurate for media of any optical thickness and is capable of handling a wide array of axisymmetric geometries and boundary conditions. Several techniques are presented to reduce computational overhead, such as employing a Swartz‐Wendroff approximation and cut‐off criteria for evaluating radiation integrals. The method is successfully tested against several cases from the literature and is applied to some additional example problems to demonstrate its versatility. Solution of a free‐boundary, combined‐mode heat transfer problem representing the solidification of a semitransparent material, the Bridgman growth of an yttrium aluminium garnet (YAG) crystal, demonstrates the utility of this method for analysis of a complex materials processing system. The method is suitable for application to other research areas, such as the study of glass processing and the design of combustion furnace systems.

The purpose of this paper is to examine to what extent the factors of the operating environment influence the structural dimensions and subsequent performance of a firm's recovery system.

Using contingency theory and a sample of 158 service firms, this research tests for structural differences in service recovery systems based on Schmenner's widely‐cited taxonomy, the service process matrix. To conduct the analysis, both multiple analysis of variance (MANOVA) and analysis of variance (ANOVA) models were tested to assess overall system differences and to detect individual dimensional differences.

The results indicate that differences in the structure of service recovery systems do exist across divergent operating environments. Additionally, differences in performance measures were found only in capability improvements, while customer‐oriented performance did not vary across operating environments.

The paper is believed to be the first to empirically investigate how differences in operating environments increase the likelihood that firms will employ divergent recovery system configurations. This work yields valuable insights into how organizations can design their systems to more appropriately respond to the demands of the environments in which they operate. The results also lend credence to the concept of equifinality, which suggests similar ends are attainable through multiple means.

This research deals with the production of electronic textiles (e‐textiles) demonstrators. Initially, the research dealt with the creation of 4×5 microphone array on a large area conformal textile substrate. Once the interface electronics were connected to the 4×5 microphone array, this system became an effective acoustic array. Here, a new acoustic eight microphone array design has been designed, fabricated and tested. Changes were made to improve microphone array performance, and to optimize the associated software for data capture and analysis. This new design was based on UC‐Berkeley mote microcomputer technology. The mote‐based system addresses the issue of scaling acoustic arrays, to allow for distributing microphones over large‐areas, and to allow performance comparisons to be made with the original 4×5 microphone acoustic array.

The paper presents a new approach to texture analysis. The need for a more formal definition of the term surface texture is first identified, and an appropriate texture taxonomy proposed. A method of analysis is described, synthesising innovative elements of machine vision and computer graphics to achieve an object‐centred inspection technique, which is both robust and flexible in application. A selection of experimental results is presented in the paper.

This study aims to investigate projects as social exchange networks, focussing on identifying knowledge brokers within the project network where they are key holders and disseminators of end-user needs. The purpose is to augment current theory through a practice lens so that building end-user requirements can be better incorporated in evolving project ecosystems.

An interpretive, an inductive case study is used to map knowledge brokers during a complex construction and co-location project. During the wider study, a variety of methods including archival data, interviews and questionnaires along with social network analysis (SNA) were used. The mixed methodology used has been pivotal in the triangulation of data from various sources. However, the output of SNA presented in this paper relies mostly on interviews and questionnaires administered to the project’s core network. Network relationships were mapped with knowledge of user requirements, being the key determinant of the binary relationships between actors.

The research found certain roles to be central knowledge brokers of knowledge related to end-user processes, including real estate and strategic planning, building operations and management, human and environmental factors, planning and project management and facility and service delivery. The knowledge of the above roles, albeit in a contextually situated case study, augments current understanding of which roles to tap on during project execution for better representation of end-user needs.

The research site is representative of a complex network of construction project stakeholders, including several categories of end-users and their representatives. The study demonstrates the use of the project-as-practice approach, whereby project theory is seen to emerge directly from practice. This has impact on practice as emergent theory about knowledge transfer and knowledge brokerage is essentially practice-led and hence more useful and relate-able to practitioners.

Research presented here is novel in terms of its approach towards understanding end-user needs such as need for privacy, control, attachment and interaction during construction projects. This is done through the identification of relevant knowledge brokers. The study uses SNA as an analytical tool to map knowledge transfers through the project’s network. End-user requirements are usually captured in the front-end of projects as specifications and deliverables, as new challenges emerge during execution, changes are required to the project’s direction and outcomes. It is therefore imperative that end-user needs are re-identified through knowledge brokers holding key knowledge. This allows project managers to prepare appropriate responses to changing project ecosystems.

The purpose of this paper is to present a computationally efficient model to solve combined conduction/radiation heat transfer problems in absorbing, emitting, non‐scattering, non‐gray materials.

The model is formulated for steady‐state condition and based on an iterative approach where the medium is discretized into finite strips and the extinction spectrum is divided into finite bands to consider the extinction coefficient variation with the wavelength.

Temperature fields and heat flux distributions are presented to demonstrate the capability of the formulation. It is shown that the model is quite accurate and efficient even for the cases of pure radiation. Differently from other models, the number of iterations required by the model for convergence is very low, even in the cases dominated by radiation.

The model has great potential to contribute with the evaluation and design of materials for thermal insulation, where radiation heat transfer can be the dominant mechanism, such as aerogel materials which are recognized as the solids with the lowest thermal conductivity and are intended to be used in building and construction, aerospace, transportation and other applications.