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This paper reports on pulsed DC sputtering of AlN film on top of Si (111) substrate. First, we tabulate major articles on reactive sputtering of AlN film on top of Si (111) substrate that were published in past 30 years. Then, we propose sputtering recipe to produce consistent and high crystal quality (as measured by FWHM of rocking curve) of AlN film across varying substrate temperature (250 to 450 ˚C) and sputtering powers (1200 to 2400 W). In addition, we demonstrate influence of both parameters to in‐plane stress, in agreement with similar trends that are reported in literature for AlN films on other substrates. The best sample is produced at substrate temperature of 350 ˚C and sputtering power of 1800 W, resulting in FWHM of rocking curve of 1.84o, surface roughness of 1 nm, and in‐plane stress of +300 MPa. The recipe from this work will be beneficial for integration of AlN thin film in CMOS and MEMS processes.

Aluminum Nitride (AlN) thin films are successfully deposited on epitaxial 3C-SiC-on-Si (100) substrates using DC magnetron sputterer. The sputtered films are characterized on the following parameters: crystal orientations (Siemens D500 X-Ray diffraction tool), deposition rate (Nanospec AFT 180), surface roughness (Park NX20 Atomic Force Microscopy), refractive index (Rudolph AutoEL IV Ellipsometer), in-plane stress (Tencor Flexus 2320 System) and Raman Spectra (Rennishaw InVia Spectrometer). XRD results demonstrate that the orientation of the AlN thin films can be changed from (002) to (101) by increasing the Nitrogen to Argon ratio from 40% to 80% at the total gas flow of 50 sccm. We are also able to tune the in-plane stress via RF biasing on the substrate. Both controlling abilities enable the applications of these thin films for low cost longitudinal piezoelectric devices and a quasi-shear mode devices using (002) and (101) orientations, respectively.

In this paper, we deposited c-axis oriented ZnO thin films on top of epitaxial 3C-SiC/Si (100) substrates using RF magnetron sputtering. We investigated the effect of O2/Ar ratio and the post-annealing temperature. The grazing angle incident x-ray diffraction results show that ZnO thin-films are highly oriented along the (002) crystalline direction between the O2/Ar ratio of 30% to 50%, at the post-annealing temperature of 600 ˚C in nitrogen environment. The recipe from this work can be used to develop low cost piezoelectric devices such as an energy harvester.

Controlled actuation of a floating liquid marble, a liquid droplet coated with hydrophobic particles floating on another liquid surface, is a potential digital microfluidics platform for the transport of aqueous solution with minimal volume loss. This paper reports our recent investigation on the magnetic actuation of floating liquid marbles filled with magnetic particles. The magnetic force and frictional force acting on the floating liquid marble determine the horizontal movement of the marble. We varied the magnetic flux density, flux density gradient, concentration of magnetic particles and speed of the marble to elucidate the relationship between the acting forces. We subsequently determined the suitable operating conditions for the actuation and derived the scaling laws for the actuation parameters.

Modelling and simulation of the dynamic indoor relative humidity behaviour of a building is essential to test any proposed thermal comfort controller and strategy in the building. Like other plants, the dynamic indoor relative humidity behaviour of a building can be developed based on the white box model, black box model, and grey box model. This research focuses on the usage of autoregressive–moving-average (ARMA) model, a type of black box model to represent the dynamic indoor relative humidity behaviour of Industrial Instrumentation Laboratory at Malaysia-Japan International Institute of Technology (MJIIT), UniversitiTeknologi Malaysia (UTM) Kuala Lumpur and uses the real recorded data from the laboratory and minimal knowledge regarding the physical characteristics of the humidity behaviour in the laboratory. The performance of the ARMA model developed in this research is compared with the real recorded data from the laboratory. Result obtained shows that the ARMA model is enough for modelling and simulating the dynamic indoor relative humidity behaviour of the laboratory

Bioconvective flows have attracted attention in recent years due to actual and potential applications. In this paper, we consider a steady and laminar convective MHD flow of a nanofluid with heat, mass and microorganism transfer with a heat source/sink present. In addition, we assume there exists a first order chemical reaction. The governing partial differential equations (PDEs) are reduced to ordinary differential equations (ODEs) using the scaling group transformation and the associated boundary value problem is then solved. The influences of selected governing parameters on the dimensionless velocity, temperature, nanoparticle concentration, density of motile microorganisms, skin friction, heat transfer, mass transfer, and motile microorganism density rates are computed and discussed

This paper investigates the effect of squeeze film damping on a micromechanical structure that oscillates due to the pressure distribution on moveable top plate that pair with perforated backplate. The damping characteristics are analytically evaluated to establish the optimum design that increase dynamics performance. The squeezed film damping governing equation, the Reynolds equation, is the fundamental equation of this work. The damping coefficient, air gap damping and viscous damping are calculated by using Skvor's formula. The size of perforation holes and air gap thickness that influencing the squeeze film damping were studied. Analytical solution with various holes structure are summarized. Overall, the 3µm of hole radius, 50µm of holes center-to-center distance and 4µm of air gap thickness were found to be the best in order to reduce squeeze film damping in capacitive microphone.

We present the mixing and merging of two reactive droplets on top of an open surface. A mobile droplet (1.0 M HCl solution + iron oxide particles) is magnetically-actuated to merge with a sessile droplet (1.0 M NaOH + phenolphthalein). The heat from the exothermic reaction is detected by a thermocouple. We vary the droplet volume (1, 5 and 10 &mu, L), the magnet speed (1.86, 2.79, 3.72 and 4.65 mm/s) and the iron oxide concentration (0.010, 0.020 and 0.040 g/mL) to study their influences on the mixing time, peak temperature and cooling time. The sampled recording of these processes are provided as supplementary files. We observe the following trends. First, the lower volume of droplet and higher speed of magnet lead to shorter mixing time. Second, the peak temperature increases and cooling time decreases at the increasing speed of magnet. Third, the peak temperature is similar for bigger droplets, and they take longer to cool down. Finally, we also discuss the limitations of this preliminary study and propose improvements. These observations could be used to improve the sensitivity of the open chamber system in measuring the exothermic reaction of biological samples.

This paper reports the mechanical analysis of bending test for Si and 3C-SiC materials. The analytical experimental were determined by using a standard three-point micro-bend test method (ASTM E290) to be applied on MEMS capacitive pressure sensor diaphragm. The MEMS device was fabricated into 5.0 mm x 5.0 mm square shape with the thicknesses of 680 μm and 1.0 μm thin film on 3C-SiC-on-Si wafer. The bending test is performed to determine the maximum stress during heat treatment up to 1000 °C and the load is applied until the 3C-SiC-on-Si wafer fracture. The test results indicated that 3C-SiC has good fatigue properties when heated up to 1000 °C with the maximum load of 52.72 N directly bring out the maximum stress and maximum strain of 104.95 MPa and 3.2%, respectively. This approach can be compared to Si, the material no longer withstand with the maximum load is 1.30 N only with the maximum stress is 10.13 MPa and maximum stain is 1.0%.

Introduction: The Cervical Vestibular Evoked Myogenic Potential (cVEMP) is used to evaluate the integrity of saccule and inferior vestibular nerve. There are a lot of factors affecting cVEMP results including stimulus types. This study was carried out to determine the effects of different stimuli on cVEMP results and its test-retest reliability. Materials and method: 25 normal hearing subjects were recruited. The cVEMP testing were performed in 2 sessions with 1 week gap between each sessions. The cVEMP waveforms were recorded in sitting upright position with electrodes placed at; i) upper one-third of sternocleidomastoid muscle for active electrode, ii) suprasternal notch for inactive electrode and, iii) middle of forehead for the ground electrode. The stimuli (500Hz tone burst, click, narrowband chirp and broadband chirp) were presented via insert phone at 95dBnHL. The cVEMP results (P13-N23 peak-to-peak amplitude, P13 latency and N23 latency) were recorded. Results: Result showed; i) 500Hz tone burst produced significantly largest amplitude; ii) narrowband chirp produced significantly shortest P13 latency; iii) broadband chirp produced significantly shortest N23 latency; iv) no significant difference of P13 and N23 latency were observed between two sessions; and v) significant difference of P13-N23 amplitude were observed between two sessions for all stimuli except for narrowband chirp. Conclusion: The 500Hz tone burst was observed to be the most ideal stimulus (produce highest amplitude). All stimuli produced good test-retest reliability in terms of latency. However, most of the stimuli produced poor test-retest reliability in terms of amplitude except for narrowband chirps.

In this project, SiC based MEMS capacitive microphone was developed for detecting leaked gas in extremely harsh environment such as coal mines and petroleum processing plants via ultrasonic detection. The MEMS capacitive microphone consists of two parallel plates; top plate (movable diaphragm) and bottom (fixed) plate, which separated by an air gap. While, the vent holes were fabricated on the back plate to release trapped air and reduce damping. In order to withstand high temperature and pressure, a 1.0 μm thick SiC diaphragm was utilized as the top membrane. The developed SiC could withstand a temperature up to 1400°C. Moreover, the 3 μm air gap is invented between the top membrane and the bottom plate via wafer bonding. COMSOL Multiphysics simulation software was used for design optimization. Various diaphragms with sizes of 600 μm2, 700 μm2, 800 μm2, 900 μm2 and 1000 μm2 are loaded with external pressure. From this analysis, it was observed that SiC microphone with diaphragm width of 1000 μm2 produced optimal surface vibrations, with first-mode resonant frequency of approximately 36 kHz. The maximum deflection value at resonant frequency is less than the air gap thickness of 8 mu;m, thus eliminating the possibility of shortage between plates during operation. As summary, the designed SiC capacitive microphone has high potential and it is suitable to be applied in ultrasonic gas leaking detection in harsh environment.

This paper reports the dynamic behaviour of a magnetically actuated floating liquid marble by analysing the oscillation of the marble. A liquid marble is a liquid droplet coated with hydrophobic powder. Magnetite particles inside the marble make it magnetic. The marble floats on a carrier liquid that contains aqueous glycerol of various concentrations. A permanent magnet located under the carrier liquid drives the floating marble with the initial velocity. Stopping the magnet abruptly causes the marble to oscillate around its final position for a few seconds. The oscillation was recorded and analysed using customised image processing and evaluation software. The damped harmonic motion model was then applied to the data and tested. Subsequently, critical parameters of the system such as the initial displacement, friction correction factor, the apparent frequency and the spring constant were determined and discussed. The simple experimental set-up and convenient theoretical approach allow us to characterise the marble motion under the influence of a magnet with good accuracy.

We report on the radio frequency (RF) sputtering of c-axis oriented ZnO thin films on top of epitaxial 3C-SiC-on-Si (111) substrates, which were then subjected to post-annealing treatment at 400, 600 and 800 °C. Grazing incident X-ray Diffraction (XRD) data show that the Full Width Half Maximum (FWHM) values for O2/Ar ratios between 30% and 60% are consistent, with a mean of 0.325° and a standard deviation of 0.03°. This is largely attributed to the smaller lattice mismatch of 5% between the ZnO (002) and SiC (111) films. The quality of the ZnO films deteriorated at the post-annealing treatment of 800 °C, as demonstrated by the increasing value of FWHM diffraction peaks, the reducing value of the peak intensity, the reducing percentage of (002) oriented area under the curve, and the increasing value of biaxial stress. We propose a simple growth model to explain the result.

The effect of multiple slip on a chemically reactive magnetohydrodynamic (MHD) non-Newtonian power law fluid flow over a stretching sheet with microorganism was numerically investigated. The governing partial differential equations were transformed into nonlinear ordinary differential equations using the similarity transformations developed by Lie group analysis. The reduced governing nonlinear ordinary differential equations were then numerically solved using the Runge-Kutta-Fehlberg fourth-fifth order method. Good agreement was found between the present numerical solutions with the existing published results to support the validity and the accuracy of the numerical computations. The influences of the velocity, thermal, mass and microorganism slips, the magnetic field parameter and the chemical reaction parameter on the dimensionless velocity, temperature, nanoparticle volume fraction, microorganism concentration, the distribution of the density of motile microorganisms have been illustrated graphically....

Natural disasters are common nowadays and a major adverse event resulting from natural process of Earth. Most of the natural disaster are beyond control of human beings and cannot be predicted accurately when it occurs. For instance, prediction of a river water level is essential for flood mitigation in order to save people’s lives and property. However, it is very difficult to predict river water level accurately since it is influenced by many factors and the fluctuations are highly non-linear. To address this problem, a river water level predictor utilizing the Radial Basis Function Network (RBFN) is proposed in this study. The goal of this project is to design a neural prediction algorithm that can forecast river water level prediction 7 h ahead with lower error. Result shows Best Fit value of 82.43% and Root Mean Square Error (RMSE) of 1.571.

This works reports a packaged MEMS capacitive pressure sensor (CPS) employing single crystal 3C-SiC thin film as a diaphragm. The details of the design and fabrication steps involved bulk micromachining process. The 3C-SiC-on-Si wafer is back-etched the bulk Si to leave 3C-SC thin film by applied ProTEK PSB coating as a newly photosensitive layer. The ProTEK PSB is exposed into desired pattern of MEMS capacitive pressure sensor and the exposed pattern is developed by developer (ethylene lactate). The photosensitive can be stripped off with strong combination acid such as 2-(1-methoxy)propyl acetate, ethyl acetoacetate and photoacid generator which is attack the exposed ProTEK PSB while unexposed ProTEK PSB areas remain contact the alignment on the wafer surfaces. The prototypes of a MEMS capacitive pressure is packaged for high temperature up to 500 °C and characterized under static pressure of 5.0 MPa in a stainless steel chamber with direct capacitance measurement using LCR meter. The diaphragm of 3C-SiC thin film has the thicknesses of 1.0 µm and the size of 2.0 × 2.0 mm. At room temperature (27 °C), the sensitivity of the sensor is 0.00962 pF/MPa in the range of (1.0---5.0 MPa), with nonlinearity of 0.49 %. At 300 °C, the sensitivity is 0.0127 pF/MPa, and nonlinearity of 0.46 %. The sensitivity increased by 0.0031 pF/MPa, corresponding temperature coefficient of sensitivity is 0.058 %/ °C. At 500 °C, the maximum temperature coefficient of output change is 0.073 %/ °C being red at 5.0 MPa. The main impact of this work is the ability of the sensor to operate up to 500 °C, compare to the previous work using similar 3C-SiC diaphragm that can operates only 400 °C. The main impact of this work is the ability our CPS to operate up to 500 °C and pressure of 5 MPa to surpass the performance of previous work at lower temperature and pressure. In addition, this CPS has reliable stainless steel (SS) o-ring packaging with a direct assembly approach to reduce manufacturing cost and easy installation and maintenance environment.

This study develops the prototype of a micro-electro-mechanical systems (MEMS) packaged capacitive pressure sensor employing 3C-SiC thin film as a diaphragm. The details of the design and fabrication steps involved bulk micromachining process. The 3C-SiC-on-Si wafer is back-etched the bulk Si to leave 3C-SC thin film by applied ProTEK PSB coating as a newly photosensitive layer. The ProTEK PSB is exposed into desired pattern of MEMS capacitive pressure sensor and the exposed pattern is developed by developer (ethylene lactate). The photosensitive can be stripped off with strong combination acid such as 2-(1-methoxy)propyl acetate, ethyl acetoacetate and photoacid generator which is attack the exposed ProTEK PSB while unexposed ProTEK PSB areas remain contact the alignment on the wafer surfaces. The prototypes of a MEMS capacitive pressure is packaged for high temperature up to 500 °C and characterized under static pressure of 5.0 MPa in a stainless steel chamber with direct capacitance measurement using LCR meter. The diaphragm of 3C-SiC thin film has the thicknesses of 1.0 µm and the size of 2.0 mm × 2.0 mm. At room temperature (27 °C), the sensitivity of the sensor is 0.00962 pF/MPa in the range of (1.0---5.0 MPa), with nonlinearity of 0.49 %. At 300 °C, the sensitivity is 0.0127 pF/MPa, and nonlinearity of 0.46 %. The sensitivity increased by 0.0031 pF/MPa, corresponding temperature coefficient of sensitivity is 0.058 %/°C. At 500 °C, the maximum temperature coefficient of output change is 0.073 %/°C being red at 5.0 MPa. The main impact of this work is the ability of the sensor to operate up to 500 °C, compare to the previous work using similar 3C-SiC diaphragm that can operates only 400 °C. In addition, a reliable stainless steel o-ring packaging concept is proposed as a simple assembly approach to reduce the manufacturing cost. There is an o-ring seal a this sensor is designed for high reliability, small size, lightweight, smart interface featured and easy cleaning service in the field which is relatively easy to replace without the need for special skill or tools in short period of time.

The 680 µm thick wafer is back-etched, leaving the thin film 3C-SiC as the flexible diaphragm to detect pressure. The etching processes are performed with three different KOH concentrations (35, 45 and 55 %), without and with 10 % IPA surfactant and the etching temperatures of 50 and 80 °C. Graphs are plotted on the effect of the etch rate and etch depth against these three parameters. In addition, the surface roughnesses of the diaphragms at these conditions are measured, photographed and analyzed. The results show that the back-etching of a 3C-SiC-on-Si wafer is fastest at higher temperature and KOH concentration and without IPA surfactant, but at the price of higher surface roughness. The addition of 10 % IPA reduces the surface roughness significantly. We also notice the increasing presence of micro-pipes at higher KOH concentration and etching temperature. The experiments are performed using bulge test method that induces the effects of dimensional layout diaphragm of 2,000 and 2,500 µm, the curve shows a good resemblance each other at pressure of 5.0 MPa. The maximum difference linearity of 2,000 and 2,500 µm is 98.7 and 97.1 %, respectively. It is revealed that the small layout dimensional can sustain the diaphragm at high pressure compare with large dimensional layout of 3,000 and 3,500 µm with the linearity is about 73.2 and 62.6 %, respectively.

The (100) and (111) crystalline cubic silicon nitride (3C-SiC) thin films have been epitaxially deposited on (100) silicon substrate with the thickness of 0.5 µm and 1.0 µm. The effects of the different growth of 3C-SiC are considered as the most critical factor in determining the mechanical properties by comparing with bulk value such as Young’s modulus (~455 GPa) and hardness (~42 GPa). This paper evaluates the mechanical characteristic of the 3C-SiC-on-Si wafers to improve the 3C-SiC thin film quality. The aim is to employ the thin film as the flexible diaphragm in the MEMS capacitive pressure sensor for extreme environment. The surface morphology of thin layer of grown 3C-SiC wafers are characterized by X-ray diffraction (XRD), Infinite Focus Microscopy (IFM), scanning electron microscopy (SEM) and nano-indentation test. The results show the superior mechanical strengths of both (100) and (111) 3C-SiC thin films over (100) Si. To conclude, these results show that (100) and (111) 3C-SiC are indeed high quality thin film mechanically compare to (100) Si thin film, and is suitable to employed as the flexible diaphragm of the MEMS capacitive pressure sensor for extreme environments.

This paper presents the optimized design and Finite Element Analysis (FEA) of a bio sensor based on cubic silicon carbide (3C-SiC) for pathogen detection. Silicon Carbide is chosen due to its excellent material properties and chemical stability compared to silicon in varying environmental conditions. The desired resonance frequency is optimized using matlab and the finite element analysis is carried out using COMSOL and Intellisuite software’s. The effect of the residual stress on the desired mode of resonant frequency and the fabrication feasibility of the proposed resonator fabrication are studied using FEA analysis. The mathematical modeling of thermally actuation and piezoresistive sensing for the design resonator bio sensors are illuminated. The close agreement between the analytical model and finite element analysis verify the design of proposed bio sensors.

The logistics industry is an ever growing industry not only in Malaysia but also in other parts of this world. Rather than being viewed as a supportive industry to other functional areas previously, now, logistics has been regarded as a strategic industry on its own. In the Asia Pacific region, the potential for growth is very promising. Logistics has emerged from merely a supporting activity that facilitates trade to a crucial sector by which the nation's competitiveness is measured. In other countries especially highly advanced countries such as United States of America and United Kingdom, logistics had already become prominent and acknowledged as a critical factor of competitive advantage and the increasing importance is due on the expansion of the international trade as well as the globalization strategy of companies in their respective business and Malaysia has no exception on this particular issue. To make sure logistics industry together with supply chain management comply with the needs of current trend in the industry, they need complete support system and one of the system is the communication system. Effective communication system is one of the crucial elements in making a smooth operations in logistics industry. This study was conducted to explore key issues related to communication systems in logistics industry. Three objectives were set, firstly to find out communication method that practiced among parties involved in logistics industry. Next is to identify patterns of communication network practiced by the main parties in the logistics industry and last but not least to identify the current problem of communication channel used in terms of disseminating information to all parties in logistics industry. The research found that good communication flow and devices is crucial in logistics industry. There are certain devices are identified as “must have” in logistics industry such as mobile phones and the research also found that most of parties involved in logistics process can be considered as technology-savvy as far as communication is concerned. This research concludes that, communication and information technology is crucial for logistics industry, therefore those who suppose to provide right from infrastructure to human capital must cope with latest needs and rapid development in both aspects.

This paper discusses the mechanical and electrical effects on 3C-SiC and Si thin film as a diaphragm for MEMS capacitive pressure sensor operating for extreme temperature which is 1000 K. This work compares the design of a diaphragm based MEMS capacitive pressure sensor employing 3C-SiC and Si thin films. A 3C-SiC diaphragm was bonded with a thickness of 380 μm Si substrate, and a cavity gap of 2.2 μm is formed between the wafers. The MEMS capacitive pressure sensor designs were simulated using COMSOL ver 4.3 software to compare the diaphragm deflection, capacitive performance analysis, von Mises stress, and total electrical energy performance. Both materials are designed with the same layout dimensional with different thicknesses of the diaphragm which are 1.0 μm, 1.6 μm, and 2.2 μm. It is observed that the 3C-SiC thin film is far superior materials to Si thin film mechanically in withstanding higher applied pressures and temperatures. For 3C-SiC and Si, the maximum von Mises stress achieved is 148.32 MPa and 125.48 MPa corresponding to capacitance value which is 1.93 pF and 1.22 pF, respectively. In terms of electrical performance, the maximum output capacitance of 1.93 pF is obtained with less total energy of 5.87 × 10−13 J, thus having a 50% saving as compared to Si.

In this work, mechanical properties of an epitaxial silicon carbide-on-silicon (3C-SiC-on-Si) sample were extracted using a Micro Materials Nanotest® indentation system. Maximum load, penetration depth and loading rate were set at 25 mN, 550 nm and 5 mN s−1, respectively. We first plot the load-depth curve of 3C-SiC film and Si substrate. Then, we find the maximum values of hardness, tensile modulus, shear strength, shear modulus and tensile stress of 3C-SiC film. The obtained data provide evidence of the suitability of this film to be applied as an electroacoustic transducer.

The ProTEX® PSB thin film as a photosensitive layer has been released in the market as an alternative replacement for silicon nitride or silicon oxide wet etch masks. In this work, this film has been deposited on SiC-on-Si wafer for the back-etching of the bulk Si to leave SiC thin film to be used as a pressure sensor diaphragm. This paper will discuss the process flow to estimate the optimized ProTEX® PSB thin film thickness for the sufficient back-etching of the 300um bulk Si. This thickness is defined by the following parameters: spin-coating rotational speed, final cure temperature and hard bake time of coating. Several samples of ProTEX® PSB thin films have been preliminary characterized by infinite focus microscopy (IFM) and scanning electron microscopy (SEM) to examine the substrate surface conditions and the effects of undercut edges structure. Based on these data, it was determined that the optimum thickness of ProTEX® PSB for this project is 2.133 μm with the spin speed of 3000 rpm, the first bake temperature of 110 °C in 120 seconds and the second bake temperature of 240 °C in 60 seconds. We conclude that ProTEX® PSB can withstand the etch mask with etch rate of 1.28 μm/min for 8 hours and gives good quality effect of undercut edge on the SiC-on-Si wafer.

A new design of microelectromechanical systems (MEMS) condenser microphone employing silicon carbide (SiC) diaphragm is proposed for the sonic detection. The sensing structure consists of SiC thin film as the top plate and perforated Si as the back plate. The numerical analysis and simulation studies compare the mechanical performances of the square-shape SiC diaphragm. Four parameters are considered i.e. resonance frequency, cutoff frequency, maximum deflection and maximum stress. The theoretical and simulated results match closely. Overall, the 680 µm × 680 µm SiC diaphragm with the thickness of 1.00 µm gives the optimized mechanical performances for the sonic detection.

Modelling and simulation of the dynamic thermal behaviour of a building is important to test any proposed thermal comfort control system and strategy in the building. A simulation model can be obtained by using either the white box, grey box or black box modelling method. This research focuses on the usage of auto regressive and moving average (ARMA) model, a type of black box model that represents the dynamic thermal behaviour of iHouse testbed and uses real recorded data from the testbed and limited knowledge regarding the physical characteristics of the testbed. The performance of the ARMA model developed in this research is compared with the performance of House Thermal Simulator, a previously developed model, based on grey box modelling. Results obtained shows that ARMA model works better than House Thermal Simulator in some aspects.