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Cold-formed steel portal frames are a popular form of construction for low-rise commercial, light industrial and agricultural buildings with spans of up to 20 m. In this article, a real-coded genetic algorithm is described that is used to minimize the cost of the main frame of such buildings. The key decision variables considered in this proposed algorithm consist of both the spacing and pitch of the frame as continuous variables, as well as the discrete section sizes. A routine taking the structural analysis and frame design for cold-formed steel sections is embedded into a genetic algorithm. The results show that the real-coded genetic algorithm handles effectively the mixture of design variables, with high robustness and consistency in achieving the optimum solution. All wind load combinations according to Australian code are considered in this research. Results for frames with knee braces are also included, for which the optimization achieved even larger savings in cost

This study investigates optimum design in terms of minimum cost of reinforced concrete cantilever retaining walls. For the optimization process, the evolutionary method which is a combination of genetic algorithm and local search techniques was implemented. Evolutionary method was adopted in this study because it can effectively solve highly nonlinear problems and problems that feature discontinuous functions as demonstrated by several works available in the literature. The popularity of the evolutionary method may also be attributed to its availability as one of the solving methods in Solver add-in tool of Microsoft Excel. This implies that it is freely available and no need to pay for extra license to run any optimization problem. The design variables of the problem are thickness of stem wall, thickness of base slab, width of the heel, width of the toe, area of steel reinforcement for the stem wall and base slab. The objective function was to minimise the total cost of the wall, which includes costs of concrete, steel, forming, and excavation. The constrained functions were set to satisfy provisions and requirements of Eurocode 2 (EC2). Material strength and soil characteristics are treated as design parameters where they are kept constants during solution of the problem. Various material cost ratios were considered. Consequently, optimum design charts were developed for a wide range of wall height, coefficient of friction and surcharge load. Following a comprehensive investigation of the minimum cost problems carried out for different cases, one can conclude that the total cost of the retaining wall is directly proportional to the wall height and surcharge load values, whereas, the cost is almost independent of coefficient of friction.

This report discusses the merits and limitations of the two main choices of learning and teaching method which are the traditional learning (t-learning) and electronic learning (e-learning) methods. On the basis of this comparison and evaluation, the report suggests the blended learning (b-learning) method as an effective alternative approach for teaching and learning process. The term b-learning is used to describe a solution that combines the traditional faceto-face classrooms, i.e. t-learning along with the elearning. The goal of blended learning is to join the best features of in-class teaching with the best features of online learning to promote active independent learning and reduce class seat time. The basic concept of blended learning, and the key steps and rules to develop a successful blended module is reviewed. The second part of the paper highlights the actual practical aspects of blended learning model currently adopted by Nottingham Trent University and its experience in this field for achieving maximum teaching objectives and learning outcomes. BackgroundWith recent advances in the science and technology of learning, there will be two main choices of learning and teaching method. Will it be electronic learning (e-learning) method? Or one of the older but tried and true classical face-to-face approach, i.e. traditional learning (t-learning) method? Professionals reveal that certain content is more effective if delivered through e-learning, while other content is more suitable for classroom instruction. Findings show that both delivery methods can successfully coexist to compose an effective and efficient training system. This report is divided into two parts. The first part reviews the advantages and disadvantages of the two teaching and learning methods: e-learning and tlearning. On the bases of the comparison of these two methods, blended learning (b-learning) method is suggested as an alternative approach for teaching and learning process.The basic concept of blended learning, advantages and the key steps and rules to develop a successful blended module is reviewed. The second part of this report highlights the actual practical aspects of blended learning model currently adopted by Nottingham Trent University and its experience in this filed for achieving maximum teaching objectives and learning outcomes. Electronic LearningElectronic Learning (e-learning) is the term used to describe teaching and learning resources or experiences that are, in some way, delivered electronically. E-learning is meant to be more than just educational websites or computer software. It includes all aspects of available electronic delivery (internet, intranets, extranets, satellite broadcast, audio/video tape, interactive TV and CD-ROM) to make teaching and learning more flexible for the students and instructors [1].For learners, e-learning knows no time zones, and location and distance are not an issue. In asynchronous e-learning, students can access the online materials at any time, while synchronous elearning allows...

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