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This paper outlines a general procedure for obtaining, on the basis of continut~m-type optimality criteria (COC), economic designs for reinforced concrete beams under various design constraints. The costs to be minimized include those of concrete, reinforcing steel and formwork. The constraints consist of limits on the maximum deflection, and on the bending and shear strengths. However, the formulation can easily cater for other types of constraints such as those on axial strength. Conditions of cost minimality are derived using calculus of variation on an augmented Lagrangian. An iterative procedure based on optimality criteria is applied to a test example involving a reinforced concrete propped cantilever beam whose cross-section varies continuously. Numerical examples are presented in which the design variables are both the width and the depth or the depth alone, and the optimal costs are compared. The solution of the test example with depth alone as the design variable is confirmed by an alternative approach using discretized continuum-type optimality criteria (DCOC).

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This study focused on examining the intergroup relations among ethnically diverse university students. The study was conducted in Bahir Dar University, one of the public universities in Ethiopia– a country of “indigenous ethnic diversity”. The participants were students, teachersand support staff selected usingpurposive and snowball sampling.The necessary data were collected throughinterview andfocus group discussion. The studyrevealed different factors that are internal and external to the university facilitateand impede intergroup relations among students. The study also showed that students generally have positive attitude toward outgroups and developing positive intergroup relations. This finding has very strong implications in managing intergroup relations not only in universities but also in the society. The university management, however, was found unable to provide much support to such positive attitudesand promoting diversity mainly because of lack of institutional priority as well as managers’ confidence and diversity management skills.DOI: http://dx.doi.org/10.3126/jer.v3i2.8399Journal of Education and Research August 2013, Vol. 3, No. 2, pp. 77-95

A procedure for the economic design of reinforced concrete beams under several design constrMnts is outlined on the basis of discretized continuum-type optimality criteria (DCOC). The costs to be minimized involve those of concrete, reinforcing steel and formwork. The design constraints include limits on the maximum deflection in a given span, on bending and shear strengths, in addition to upper and lower bounds on design variables. An explicit mathematical derivation of optimality criteria is given based on the well known Kuhn-Tucker necessary conditions, followed by an iterative procedure for designs when the design variables are the depth and the steel ratio, or the depth alone. The computer code developed in Part I can handle freely-varying design variables along the members of any multispan beam. In Part II the DCOC and computer code are developed for designs when the member cross-section is assumed to be uniform along its entire length. Several test examples have been solved to prove the accuracy and efficiency of the DCOC-based techniques.