Applied Mechanics and Materials Vol. 735

Abstract: In this study, PCR amplification of biodegradation related genes from NAR-2 bacterial consortium was accomplished. NAR-2 bacterial consortium consists of Citrobacter freundii A1, Enterococcus casseliflavus C1 and Enterobacter cloacae L17. The amplified genes were sequenced, bioinformatically analyzed and compared with the sequences from GenBank database of National Centre of Biotechnology Information (NCBI) using BLASTn and BLASTp search tools. The assembled sequences represented almost >70% of similarity to biodegradation related genes. These genes may act as a key intermediate enzyme in biodegradation pathway.

Abstract: s. Renewable sources like vegetable oil have been used to prepare many polymeric resins due to the awareness on environmental issue and depletion on petrochemical sources. In polyurethane (PU) production, petroleum based polyol such as polypropylene glycol (PPG) has been replaced with plant based polyol from canola oil, soybean oil and palm oil. However, prior to be used, these vegetable oil needs to be modify chemically or physically in order to increase their functionality. In this study, palm oil (PO) has been modify via glyceroylsis and transamidation before reacted with diphenylmethane diisocyanate (MDI) at 1:1 NCO:OH ratio in the presence of distilled water as blowing agent and silicone surfactant as foam stabilizer to produce palm oil based PU foam. FTIR study of polyol from both routes shows that main hydroxyl group (-OH) have been successfully introduced into palm oil molecular structure. It was also found that the hardness of two routes have nearly similar values which were shore D 33.6 and 35.4 respectively. Both foams have potential to be used in many non-load bearing applications such as insulator in building or electrical appliances.

Abstract: A variability of energy consumption is the total variance divided by total mean consumption. Real data shows convergence of aggregated variability with the number of customers. We investigate the mathematical reasons of this phenomenon, as well as the subtleties of convergence rate. We show that the results for convergence on real data are consistent with the prediction of a simple sum of random correlated variables.

Abstract: The Johor Bahru metropolitan area is an industrial and commercial hotspot in the region and almost any significant industrial brand has a branch here. However, the effectiveness of good and effective industrial policy has never been quantified to integrate economy and environment. Taking into account the idea ‘think globally, act locally’, with an emphasis on economy, environment integration, and introducing a Low Carbon City, by building a computable general equilibrium (CGE) model, this study successfully examined the economic impacts of new production and the usefulness of economic measure based on the simulated macroeconomic and sectoral factors. An input-output (I-O) table and social accounting matrix (SAM) is the cornerstone in designing a CGE model. Lack of input-output table has badly hampered any effects in the arena of CGE modelling in Johor Bahru City. This study, therefore, attempted to utilize the most updated 2005 input-output table of Malaysia to prepare an input-output table of Johor Bahru City along with using several statistics, including the national population census, manufacturing census and commerce census for developing an input-output table for economic analysis. Modelling results showed that the total industrial output including city GDP has increased 0.07% and 0.08% respectively in 2005. Additionally, the decreasing trends of the prices of major commodity products such as solar power( -1.53 %), electric vehicle ( -0.77%) and in cogeneration (-0.32 % ) were observed significant. Thus, new industrial formation and subsidy plan have proven as the most significant contributors. Therefore, the present research suggests to apply this model into Johor Bahru City’s economy to integrate economy and environment in a city named ‘Low Carbon City-JB’.

Abstract: Energy is an important element in human daily life. In Malaysia, about 80% of electrical energy produced from burning fuels that will cause of carbon dioxide emission to atmosphere. The effect could be reduced with less energy consumption. This project focuses on energy management strategies for energy saving that can be done on the HVAC system, air-cond, lighting and office equipment in Emergency Department, Block C Hospital Sungai Buloh. The annual profit, total cost and payment period for each research method are also studied. To implement for all major system must be link to chapter by Buiding Automation System. Major studies for this topic is to implement energy saving, calculate energy comsumption, power, area specific room, return of investment, analysis for daily cost for used, total for kWh for monthly usage.

Abstract: The negative impacts of construction activities can be controlled and reduced through identification of environmental aspects and impacts of construction activities, implementation of the mitigation measures and site monitoring on a regular basis e.g through surveillance in the framework of the Environmental Management System (EMS). Continuous improvement efforts towards traditional methods and increased needs for factual information and productivity in the environmental monitoring field have been met with latest innovations in mobile information and sensory technology options. This paper through literature aims to review the characteristic of both traditional and technology based surveillance while highlighting the on how those methods complement each other.

Abstract: The design and mathematical model of a reflective type optical gas sensor is presented. Light source is radiated at an incident angle for 10 cm gas cell with an internal diameter of 0.4 cm. At an incident angle of 1^o, optical path length obtained is 342.7886 cm, at 27^o incident angle, optical path length is 10.4926 cm and at an incident angle of 28^o, optical path length is 9.9631 cm. The model is most efficient at lower incident angles, precisely between (1^o and 27^o). Effects of variation in diameter and length of gas cell are also demonstrated.

Abstract: Accurate value of absorption cross section is required for correct measurement of ozone concentration. Measurement of ozone has been done at different altitude and pressure. However, previous work has failed to establish significant relation between pressure and ozone absorption cross section. Therefore, this work aims to establish relation between pressure and maximum ozone absorption cross section via spectralcalc.com gas cell simulator. Simulation results show maximum absorption cross section 1.148×10^-21 m² molecule^-1 and maximum absorption wavelength 255.442 nm are independent of pressure changes from 0.1 atm to 3.0 atm. Thus, measurement of ozone concentration at maximum absorption wavelength is strongly recommended due to negligible pressure dependence.

Abstract: Precise control is necessary in controlling electro-hydraulic actuator system (EHAS). However due to its nonlinearities and uncertainties, controlling hydraulic actuator system had become a challenging task that need to be solved. A proper controller can be designed when an accurate model of a system is defined. In this paper, the process to obtain an EHAS system’s model by using system identification approached is presented. System identification is chosen because this technique only requires input and output data from system in order to obtain system model. An ARX model is chosen as a model structure for EHAS. A pole assignment controller and minimum variance controller (MVC) is later been designed based on the obtained model. The simulation result shows that both controllers manage to regulate at the desired input signal. However MVC controller prove to provide a better output performance compared to pole assignment controller by minimizing the phase lagging and having a better rise time.

Abstract: A Coplanar Waveguide (CPW) wideband antenna operates from 2.69 GH to 6.27 GHz which act as reference antenna (RA) has been designed. A Dual Band AMC (DBAMC) unit cells have been proposed to operate at 2.45 GHz and 5.8 GHz. AMC is a metamaterial which mimics the behavior of zero reflection phase of Perfect Magnetic Conductor (PMC) at resonance frequency which not naturally existed in nature. Subsequently the antenna is incorporated with AMC unit cell, herein referred as Antenna with Dual Band AMC (ADBAMC). The DBAMC succesfully excites additional resonance at 2.45 GHz outside the initial operating range of standalone CPW wideband antenna. Incorporation of DBAMC to antenna achieves back lobe suppression at 2.45 GHz and 5.8 GHz. The overall average gain of AMC incorporated antenna is improved from 2.69 to 6.29 GHz as opposed to the standalone reference CPW wideband antenna. Study of surface current is also presented and discussed.