Expert systems and finite element structural analysis - a review

Finite element analysis of many engineering systems is practised more as an art than as a science . It involves high level expertise (analytical as well as heuristic) regarding problem modelling (e .g. problem specification,13; choosing the appropriate type of elements etc .), optical mesh design for achieving the specified accuracy (e .g . initial mesh selection, adaptive mesh refinement), selection of the appropriate type of analysis and solution13; routines and, finally, diagnosis of the finite element solutions . Very often such expertise is highly dispersed and is not available at a single place with a single expert. The design of an expert system, such that the necessary expertise is available to a novice to perform the same job even in the absence of trained experts, becomes an attractive proposition. 13; In this paper, the areas of finite element structural analysis which require experience and decision-making capabilities are explored . A simple expert system, with a feasible knowledge base for problem modelling, optimal mesh design, type of analysis and solution routines, and diagnosis, is outlined. Several efforts in these directions, reported in the open literature, are also reviewed in this paper

Consistency aspects of out-of-plane bending, torsion and shear in a quadratic curved beam element

Curved beams in civil engineering applications call for out-of-plane bending and torsion under the action of13; out-of-plane transverse shear loads. The design of a quadratic displacement curved beam element capable of13; representing shear deformation as in the Timoshenko beam theory requires special attention to the manner in which the shear strain is represented. Field-inconsistent representations of the out-of-plane transverse shear strain will result in a loss of efficiency and introduce spurious oscillations in the bending moment, torsional moment and shear force. The optimal field-consistent assumed strain interpolation for shear is derived and it is demonstrated to posses very high accuracy which is free from spurious force and moment oscillations

Properties of Al-doped ZnS films grown by chemical bath deposition

Zinc sulphide (ZnS) buffer layers are a cadmium free, wider energy band gap, alternative to the cadmium sulphide(CdS) buffer layers commonly used in copper indium gallium diselenide (CuInGaSe2)-based solar cells. However extrinsic doping of the ZnS is important to lower the resistivity of the layers and to improve flexibility of device design. In this work, Al-doped ZnS nanocrystalline films have been produced on glass substrates using a chemical bath deposition (CBD) method. The Al- concentration was varied from 0 at. % to 10 at. %, keeping other deposition parameters constant. The elemental composition of a typical sample with 6 at. % ‘Al’ in ZnS was Zn=44.9 at. %, S=49.8 at. % and Al=5.3 at.%. The X-ray diffraction data taken on these samples showed a broad peak corresponding to the (111) plane of ZnS while the crystallite size varied in the range, 8 – 15 nm, depending on the concentration of Al in the layers. The films with a Al-doping content of 6 at. % had an optical transmittance of 75 % in the visible range and the energy band gap evaluated from the data was 3.66 eV. The films n-type electrical conductivities and the electrical resistivity varied in the range, 107-103 Ωcm, it decreasing with an increase of the Al-concentration in the solution

Exploring the Psychological Antecedents of Attitude towards Indigenous Wetland Practices

A study was conducted in the North eastern agro-climatic zone of Tamil Nadu, India to analyze the possible impact of the psychological antecedents of attitude towards Indigenous Wetland Practices(IWPs) among the farming community. Two hundred and nine farmers were selected at random from ten blocks in three districts of the state. Their psychological characteristics and attitude towards IWPs were assessed. The mean attitude score and the mean attitude index were analysed. The highest variable index was found in the case of Progressivism and Traditionalism, followed by Self-Reliance. Environmental orientation and Decision making ability had a positive and highly significant relationship while Scientific Orientation had a negative and highly significant relationship with attitude towards Indigenous Wetland Practices.

A Grounded Exploration of Sales and Distribution Channel Structures in Thirteen Industries in India Leading to a Classification Scheme

Innovation is a fundamental virtue of marketing. In this paper, a case is made to promote the use of innovative and novel combinations of research methodologies to derive new insights of business phenomena. This study is an attempt to understand and explain the sales and distribution channel structures in thirteen different industries in India. The investigation adopted a mix of case research and grounded theoretic research methodologies in exploring the subject under scrutiny. The study offers a classification scheme for grouping marketing channels into homogenous clusters based on similarity/dissimilarity using multivariate multidimensional mapping techniques. This scheme offers to explain the variety found in structures and suggests alternative channel possibilities. Such a scheme can be used in formulating marketing strategies and in deciding upon operational issues as well. While the main setting of the reported findings is Indian, the findings may prove to be useful beyond the national setting. Usual disclaimers associated with qualitative research methodology (Gummesson 1988) apply in this case concerning the generalisability and validity of the findings. This paper’s contribution is not as much in offering a schema as it is in suggesting an analytical plan/process that helps in visualising structures and associated strategies de novo.