Search results

This study delineates the effect of cover thickness on reinforced concrete (RC) columns and beams under an elevated fire scenario. Columns and beams are important load-carrying structural members of buildings. Under all circumstances, the columns and beams were set to be free from damage to avoid structural failure. Under the high-temperature scenario, the RC element may fail because of the material deterioration that occurs owing to the thermal effect. This study attempts to determine the optimum cover thickness for beams and columns under extreme loads and fire conditions.

Cover thicknesses of 30, 40, 45, 50, 60 and 70 mm for the columns and 10, 20, 25, 30, 35, 40, 50, 60 and 70 mm for the beams were adopted in this study. Both steady-state and transient-state conditions under thermomechanical analysis were performed using the finite element method to determine the heat transfer through the RC section and to determine the effect of thermal stresses.

The results show that the RC elements have a greater influence on the additional cover thickness at extreme temperatures and higher load ratios than at the service stages. The safe limits of the structural members were obtained under the combined effects of elevated temperatures and structural loads. The results also indicate that the compression members have a better thermal performance than the flexural members.

Numerical investigations concerning the high-temperature behavior of structural elements are useful. The lack of an experimental setup encourages researchers to perform numerical investigations. In this study, the finite element models were validated with existing finite element models and experimental results.

The obtained safe limit for the structural members could help to understand their resistance to fire in a real-time scenario. From the safe limit, a suitable design can be preferred while designing the structural members. This could probably save the structure from collapse.

There is a lack of both numerical and experimental research works. In numerical modeling, the research works found in the literature had difficulties in developing a numerical model that satisfactorily represents the structural members under fire, not being able to adequately understand their behavior at high temperatures. None of them considered the influence of the cover thickness under extreme fire and loading conditions. In this paper, this influence was evaluated and discussed.

This paper aims to discuss the crises of free market capitalism in terms of its understanding of human nature. It reveals how recent market madness can be attributed to certain elements of human nature.

The paper uses a conceptual and philosophical approach to analyze crises of free market capitalism. It links both success and failure of capitalism to its understanding of human nature. It compares and contrasts economic assumptions of human nature in conventional and Islamic economics. It attempts to explain the 2008 financial crisis through a comprehensive theory of human nature.

It sheds some light on the irrational aspect of human nature as the driving factor behind the 2008 financial crisis. It elaborates on the importance of knowing self for knowing human decisions in free market economy. It concludes with the need for a comprehensive theory of human nature to predict and prevent irrational and irresponsible behaviors of populist politicians, greedy capitalists and conspicuous consumers. The paper also reflects on the 2013 Nobel Prize in economics as a victory for the study of human nature.

The paper offers a new perspective to understand crises of free market capitalism.

From 2002 to 2011, coffee-machine manufacturer Keurig Incorporated had grown from a privately held company with just over $20 million in revenues and a plan to enter the single serve coffee arena for home consumers, to a wholly owned subsidiary of Green Mountain Coffee Roasters, Inc., a publicly traded company with net revenues of $1.36 billion and a market capitalization of between $8 and $9 billion. In 2003 Keurig had introduced its first At Home brewer. Now, approximately 25 percent of all coffee makers sold in the United States were Keurig-branded machines, and Keurig was recognized as among the leaders in the marketplace. The company had just concluded agreements with both Dunkin' Donuts and Starbucks that would make these retailers' coffee available for use with Keurig's specialized brewing system. The company faced far different challenges than when it was a small, unknown marketplace entrant. John Whoriskey, vice president and general manager of Keurig's At Home division, had to consider the impact that impending expiration of key technology patents and the perceived environmental impact of the K-Cup® portion packs would have on the company's growth. Whoriskey also wondered what Keurig's growth potential was, and how the new arrangements with Starbucks and Dunkin' Donuts could be leveraged to achieve it.

The purpose of this paper was to investigate the lubricity of palm biodiesel (PB)–diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB).

Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5%, 10% and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high-frequency reciprocating rig in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported WSD is the average of the major and minor axis of the wear scar.

The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63% and 44.5%, respectively, when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b and B20) exhibited significant reduction in WSD by 49.66%, 42.84% and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b.

Incorporation of PPO and WCB in PB–diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.

Tests a new series of models which attempt to describe the relationship between advertising and sales. Describes an attempt to obtain information of this kind by investigating the effect of advertising on sales and brand shares. States that a number of researchers are now attempting to develop models to explain the workings of the market for a particular product. Emphasises that the prime area of interest of the study is the effect of advertising on sales and brand shares. States the study does not have the objective of constructing a complete marketing model involving all the variables that are thought to influence a brand's share of a product. Concludes that many results herein are disappointing, but it is perhaps too optimistic to expect the models dealt with earlier to be successful.

How a micro-founded discipline such as economics could deal with the increasing global economic reality? This question has been asked frequently since the last economic crisis that appeared in 2008. In this challenging context, some commentators have turned their attention to a new area of knowledge coming from physics: econophysics which mainly focuses on a macro-analysis of economic systems. By showing that concepts used by econophysicists are consistent with an existing economic knowledge (developed by J.S. Mill), the purpose of this paper is to claim that an interdisciplinary perspective is possible between these two communities.

The authors propose a historical and conceptual analysis of the key concept of emergence to emphasize the potential bridge between econophysics and economics.

Six methodological arguments will be developed in order to show the existence of conceptual bridges as a necessary condition for the elaboration of a common language between economists and econophysics which would not be superfluous, in this challenging context, to clarify the growing complexity of economic phenomena.

Although the economics and econophysics study same the complex economic phenomena, very few collaborations exist between them. This paper paves a conceptual/methodological path for more collaboration between the two fields.

The deployment of solar photovoltaic (PV) in higher education institutions is beneficial and critical for attaining sustainable campus goals. However, various barriers hamper the adoption of the technology, and unless these challenges are identified, formulating tailor made solutions to boost deployment will be challenging. Thus, this study aimed to identify the barriers to the deployment of PV in the public university sector in South Africa.

A critical review of the literature was conducted to identify the factors that negatively impact PV deployment. By screening the barriers identified from the literature using a conceptual framework, the barriers that were considered relevant to deployment within a university context were selected. Thereafter, the selected barriers and additional barriers recommended by panellists were verified through a three-round Delphi survey. The factors were either accepted or rejected as barriers in the sector based on the factors' mean score and interquartile range values.

The study observed that 12 barriers hamper PV deployment in the public university sector. The findings indicated that the top five barriers were the lack of incentives, lack of green building targets, lack of financial resources, high initial cost, and lack of clear policy direction. However, the study found that deployment was not hindered because there was resistance to change or uncertainty of recouping investment costs. The deployment was also not hindered because there was a lack of demand from electricity end-users or a lack of suitable installation space.

Given the lack of empirical studies on the subject in the region, the present study contributes to the body of knowledge by identifying the significant barriers that impede PV deployment in the public university sector. Furthermore, insight is provided on measures that relevant stakeholders can take to motivate and support universities to deploy the technology further.