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In this study composite and sandwich beams with homogeneous core and homogeneous or Functional Graded Materials (FGM) faces under three point bending have been confronted. The purpose of this paper is to study numerically sandwich beams with homogeneous core and homogeneous or FGM faces under three point bending and to compare the results for the stress and displacement fields with those resulted of coating – substrate and homogeneous beams. Considering a crack in the lower face sheet to study the influence of the material gradation on the stress intensity factors.

At first a static finite element analysis is performed throughout the composite and sandwich beams, which is taking into account the graded character or not of the faces. For this reason five plane models are considered in order to have a comparable study for the stress and displacement fields of composite beams, which are subjected to three point bending. Second a crack in the lower face is considered parallel to the axis of gradation. When subjected to three point bending, this crack will propagate slowly perpendicular to the lower face.

Computed distributions of the stress fields across the core material and near the interfaces are given for different materials gradation of the faces; and possible crack-initiation positions have been identified. Stress intensity factors are calculated using finite element method, and assuming linear fracture mechanics and plane strain conditions.

The originality of the proposed analysis is to investigate for the first time numerically the influence of the FGMs or homogeneous faces in the core material of sandwich beams under three point bending relative to the coating – substrate and to the homogeneous beams. Second to study the influence of a crack in the lower graded face sheet on the overall behavior of the composite beam and to investigate the influence of the material gradation on the values of stress intensity factors.

While some modern organisations have established “virtual work teams”, which are said to be comprised of people who are geographically separated and who work across boundaries of space and time using computer driven communication technologies, it is also true that many organisations remain structured around conventional face‐to‐face teams. Increasingly, the conventional face‐to‐face team is endeavouring to increase its productivity by utilising some of the technology and characteristics of the virtual team. In fact, it may not be practical any longer to draw a distinction between conventional face‐to‐face teams and virtual teams, due to the invasive nature of technology throughout most modern organisations.

Examines the effectiveness of teaching business cases using collaborative groups of students. A quasi‐experiment was conducted in which a class of students was randomly placed in face‐to‐face groups and given a case with questions to answer collectively. Then for a different case, these same students were randomly assigned to electronic case groups. The electronic groups conducted all their group interactions with their fellow group members in universities in the USA, Canada and Mexico via e‐mail over the Internet. The groups rated both their group experiences, face‐to‐face and electronic. Also each student completed the Myers Briggs personality typing instrument. The four dimensions of personality type were then correlated with the case ratings; and significance tests across the two subgroups, electronic and face‐to‐face, were assessed. While there were few significant differences across the electronic and face‐to‐face groups, the extroverts found the electronic groups to be a novel experience. This may be explained by the technical frustrations encountered by the students and the lack of richness of the electronic group exchange.

Many individuals who have no or limited experience of using electronic communication technologies (ECTs), e.g. telephone, fax, voice, and e‐mail are concerned that media like e‐mail are a limited, if not poor, way of communicating, and that they cannot replace face‐to‐face communication. Reports on research examining how relatively sophisticated ECT users use ECTs to communicate, and how electronic communication may affect face‐to‐face communication. Finds that ECTs are most effective in the administrative stages of a project rather than in the initial conceptualizing stages or final project wrap up and is the primary form of communication between co‐workers. Discusses the implications for workplace strategies that involve remote work.

Aims to develop an efficient and robust system for real‐time personal identification by automatic face recognition.

A wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme are introduced to improve the computation efficiency in the face detection task. In addition, a Gabor‐based low feature dimensional pattern is proposed to deal with the face recognition problem.

The proposal of a wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme is effective to improve the computation efficiency in the face detection task. The introduction of a low feature dimensional pattern is powerful to cope with the transformed appearance‐based face recognition problem. In addition, the use of aggregated Gabor filter responses to represent face images provides a better solution to face feature extraction.

Provides guidance in the design of automatic face recognition system for real‐time personal identification.

Biometrics recognition has been emerging as a new and effective identification technology that attains certain level of maturity. Among many body characteristics that have been used, face is one of the most commonly used characteristics and has drawn considerably large attentions. An automated system to confirm an individual's identity employing features of face is very attractive in many specialized fields.

Introduces a wavelet‐based image hierarchy and a guided coarse‐to‐fine search scheme to improve the computation efficiency in the face detection task. Introduces a Gabor‐based low feature dimensional pattern to deal with the face recognition problem.

Handling feature interaction is an unsolved issue in feature recognition approach. This paper presents a method for recognizing the presence of feature interactions. First, based on the convex hull concept, a so‐called reference face is defined. Second, by adding the reference face into the attributes adjacency graph (AAG), a modified AAG is obtained. Two general feature types, namely depression and protrusion features, are identified by the reference face. The basic features such as slots, pockets and bosses are represented by the modified AAG. Any features that remain unrecognized by the modified AAG are regarded as interacting features. The types of reference faces and feature face are also classified. Based on the kind of face classification, the interacting features are finally recognized via a process of virtual face extension and volume addition.

Most adaptive slicing implementations assume a maximum allowable cusp height which applies to the entire part. Practically speaking, however, most parts do not have uniform cusp height requirements. Some faces are required to be smooth while other faces are relatively unimportant. With a uniform cusp height implementation, users must specify the most stringent cusp height which applies to the entire part. However, with non‐uniform cusp height specifications, it is possible that further gains in adaptive slicing efficiency can be achieved. This paper presents an approach to specifying non‐uniform cusp height requirements. First, a procedure is developed which uses an edge finding algorithm to identify faces on the part. The faces are then rendered using the OpenGL graphics libraries, and the user is prompted to enter the maximum allowable cusp height for each highlighted face. Implementation details and test results are presented.

An extensive bibliography exists on sandwich construction; it is felt, however, that few of the available papers are readily adaptable for use in aircraft design offices. This paper, whilst based on an existing theory, extends it to include panels with faces of unequal thicknesses and aeolotropic cores such as honeycomb. The various modes of failure are described, and comparisons are drawn between the equilibrium equations and those derived in the theory of solid plates. A very simple equation for the overall instability of a sandwich panel is obtained, based on the concept of ‘width reduction factors’ which make allowance for core flexibility and unequal face thicknesses. Methods are described for presenting these reduction factors' and other important parameters in the form of data sheets, of which examples are given. The panels which are discussed are assumed to be flat, and compressed by a load uniformly distributed across their ends. The edges, which are simply‐supported, are taken to be long in relation to the panel width.

November 23, 1972 Master and Servant — Breach of statutory duty — Mine — Management's duty to ensure suitable appliances “readily available” — Supplies available between shifts at colliery stores — Need for tool at coal face during shift — Whether system complying with regulation — Coal and Other Mines (Managers and Officials) Regulations, 1956 (S.I. 1956 No. 1758), reg. 2.