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Kuala Selangor, Malaysia

Chen S.-D.,University of Tenaga Nasional
Digital Signal Processing: A Review Journal | Year: 2012

Absolute Mean Brightness Error (AMBE) and Entropy are among the two most popular IQMs used to assess Histogram Equalization (HE) based techniques. To the best of author's knowledge, there is no evaluation report on how well the two IQMs correlate to human opinion. This paper reviews and discusses the potential flaws in using AMBE and Entropy to assess HE-based techniques. This paper presents results of a subjective quality assessment in which image quality data obtained from 1935 human observer opinion scores were used to evaluate the IQMs. The statistical evaluation results show that the two IQMs have poor correlation with human mean opinion score (MOS); Pearson Correlation Coefficient (PCC)<0.4, Root Mean Square Error (RMSE)>0.75, Outlier Ratio (OR)>20%. A new IQM which takes into account important properties of human visual perception (HVP) is proposed. It is tested and found to have significantly better correlation (PCC>0.86, RMSE<0.39 and OR=0%). The proposed IQM also outperforms Multi-Scale Structural Similarity (MSSIM) and Information Fidelity Criterion-based (IFC) measure, which are two prominent fidelity-based IQMs. © 2012 Elsevier Inc. All rights reserved. Source

Tarlochan F.,University of Tenaga Nasional | Ramesh S.,University of Malaya
Composite Structures | Year: 2012

Polymer composite sandwich structures are promising candidate structures for reducing vehicle mass, thereby improving the fuel economics. Nonetheless, to fully explore this material as the primary structure and energy absorber in vehicles, it is important to understand the energy absorption capability of this material. Hence, in the present work, comprehensive experimental investigation on the response of composite sandwich structures to quasi-static compression has been carried out. The crashworthiness parameters, namely the peak force, absorbed crash energy, specific absorbed energy, average crushing force and crush force efficiency of various types of composite sandwich structures were investigated in a series of edgewise axial compression tests. The tested composite sandwich specimens were fabricated from glass and carbon fiber with epoxy resin. Four distinct modes of failure were observed and recorded. The primary mode of failure observed was progressive crushing with high energy absorption capability. The optimized design in this study had a specific energy absorption capability of 47.1. kJ/kg with a good crush force efficiency of 0.77, higher than conventional metals. © 2011 Elsevier Ltd. Source

Shamsuddin A.H.,University of Tenaga Nasional
Procedia Engineering | Year: 2012

Malaysia introduced renewable energy as the 5th fuel strategy in the energy-mix under the National Energy Policy in 2001. A target was set at 500 MW grid-connected power generations by 2005 from renewable energy sources. The small renewable energy power program (SREP) was launched at the same time with fiscal incentives to support this initiative. Malaysia has huge potential renewable energy resources in the form of biomass, solar and hydro. However, the implementation of SREP was not up to expectation due to several barriers and challenges faced by the authorities and developers, and the target was revised in 2006 to 350 MW by 2010. At the COP15 in Copenhagen, Malaysia pledged a voluntary reduction of up to 40% in terms of emissions intensity of GDP by the year 2020 compared to 2005 levels. With this commitment the Renewable Energy Act (RE Act 2010) was enacted in 2011 with provision of Feed-in Tariff, providing more attractive incentives to spur the implementation of grid-connected power generation from renewable energy resources. With the new RE Act2010, the target is revised to 985 MW by 2015, 2,080 MW (2020) and to 21,000 MW in 2050. This paper describes the development of renewable energy policy framework, strategies and initiatives for renewable energy implementation in Malaysia, in an effort to reduce carbon emissions as pledged at the COP15. This paper also provides examples of renewable power generation currently implemented and the on-going research and development activities to enhance the exploitation of renewable energy resources in Malaysia. © 2012 The Authors. Source

Abstract The world is facing sustainability crisis as the survivability of natural environments and biota life continues to be threatened due to extensive usage of non biodegradable and polluting substances for producing cement-based materials. One alarming situation is the acceleration of global warming and climate change as a result of carbon dioxide release from cement manufacturing to the atmosphere. In another negative scenario, the widespread application of conventional water repellents such as silane and siloxane on cement-based materials poses a serious environmental threat due to their non biodegradability in nature. A viable solution that can be strategized to tackle the environmental issues is to utilize calcite from Bacillus genus bacteria for microbial cementation with the aim to optimize the mechanical behavior of cement-based materials. Bacillus genus bacteria are largely found in natural environments. Their capability to cultivate easily, absorb heavy metals and biocrystallize to form calcite has made the bacteria the promising microbes for biomineralization purpose in construction industry. This article reviews the positive influence of the bacteria at inducing calcite precipitation on cement-based materials. The rates of urea hydrolysis, calcite saturation and calcite precipitation of the bacteria which largely depend on the conditions of growth such as pH, temperature, bacterial cell concentration, calcium concentration and urea concentration are elucidated. Subsequent discussion concentrates on the current trend of crack reparation and surface treatment of cement-based materials, the prospect of developing biomineralized materials using the bacteria, and heavy metal biosorption of the bacteria. © 2015 Elsevier Ltd. All rights reserved. Source

Mohammed B.S.,University of Tenaga Nasional
Construction and Building Materials | Year: 2010

Many research works have been conducted to study the fresh and hardened properties of concrete containing crumb rubber as replacement to fine aggregate. The outcome of these researches indicated that though the compressive and flexural strength of crumb rubber concrete (CRC) decreased as percentage of fine aggregate replacement increased; the CRC has lower unit weight, better slump values, better toughness and absorb more energy before failure. In view of the fact that the main strength of composite floor slab lies within the bond between the concrete and the profiled steel sheeting, therefore the using of more ductile concrete such as CRC to toping the profiled steel sheeting could produce a new composite slab system. Two sets of slabs; each set comprising three CRC composite slabs and one conventional concrete slab has been tested with two shear span (450 and 900 mm). The results showed that the CRC slabs behavior could be characterized as ductile, while the m-k value has been found to be 80.7 and 0.037, respectively. © 2009 Elsevier Ltd. All rights reserved. Source

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