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Recent years have seen the rapid growth in the applications of wireless sensor network (WSN) which is due to the advances of sensor nodes with low cost and tiny size. Despite the various potential applications of WSN, one of the key tasks in sensor network design is to make sure that the network is functional as long as possible. This paper presents an energy-efficient cluster head selection algorithm for the clustering of heterogeneous WSN, inspired by Imperialist Competitive Algorithm (ICA). In order to reduce the network energy consumption and subsequently increases the sensor network lifetime, the clustering problem is transformed into an optimization problem and the specific cost function is used to select the cluster heads in a way that the energy utilization of the network is optimized. Extensive simulation works are done based on MATLAB to test the algorithm in various network scenarios, with different network sizes and number of nodes. Simulation results have shown that the proposed algorithm is able to extend the network lifetime compared to its comparative by up to 154 percent in terms of first node death. Furthermore, choosing the optimum set of cluster heads at every round has proved that our proposed algorithm not only could reduce the network energy consumption, but also improves the total data delivery at the base station up to 59 percent compared to the well-known algorithm.

Landfills generate leachate that contains elevated concentration of contaminants and is hazardous to human health and the ecosystem. In this study, the mixture of granular feldspar and cockle shells was investigated for remediation of COD and ammonia from landfill leachate. All adsorbent media were sieved to a particle size between 2.00 and 3.35 mm. The results revealed that the optimum mixing ratio of feldspar and cockle shells was 20:20, shaking speed was 150 rpm, pH level was 6, shaking time was 120 min, and dosage was 30 g. The adsorption isotherm analysis reveals that the Langmuir isotherm yielded the best fit to experimental data as compared to the Freundlich isotherm. The media produce encouraging results and can potentially be used as a good and sustainable adsorbent.

In this paper, a conceptual framework for a non destructive testing to check defect on composite material using parallel plate electrical capacitance tomography is being proposed. At the early stage, the possibility of using this method is being simulated using Comsol Multiphysic software. The simulation process has shown promising results to make this concept works. When a dielectric material is placed between the parallel plates, the permittivity distribution can be observed. As the number of electrodes of the sensor are increased from 2 to 8 electrodes, the capacitance value increase from 2.0131e-11-2.3532e-14i F to 5.2474e-11-3.0756e-13i F. Furthermore, there are significant results when the size and the permittivity of the object are varies.

To evaluate an air-conditioning system performance on board is quite cumbersome and tedious process due to the limitation of space in the engine compartment. This paper presents the process of designing and the result from the automotive refrigeration system simulation that have been integrated into the test rig. To perform the test on automotive refrigeration simulator the location for the temperature measurement selected and thermocouples were installed. The locations of the temperature probes are at the inlet and outlet of compressor, condenser outlet and the inlet of the evaporator. The gas pressure was measured at low and high pressure sides located at evaporator outlet and receiver-drier respectively. The test results were analyzed using the properties table of the refrigerant used. The coefficient of performance (COP), cooling load of the system and compressor power consumption were determined. The variable parameters used are the evaporator blower speed and the air velocity passes through the condenser. The experimental results obtained show that increasing the blower speed will reduce the COP of the refrigeration system. The maximum COP of the system is 4.3 at the lowest evaporator blower speed. The power consumption will be reduced when the air flow velocity through the condenser is increased from 0, 40, 50, 60, 70 km/h respectively.

A cooling system employed in an automobile is to maintain the desired coolant temperature thus ensuring for optimum engine operation. Forced convection obtained by means of a water pump will enhance the cooling effect. Thus it is necessary to understand the system’s pump operation and be able to provide for the ultimate cooling of the engine. The objective of this laboratory investigation is to study the water pump characteristics of an engine cooling system. The crucial water pump parameters are the head, power, and its efficiency. In order to investigate the water pump characteristic a dedicated automotive cooling simulator test rig was designed and developed. All of the data obtained are important towards designing for a more efficient water pump such as electric pump that is independent of the power from the engine. In addition to this fact, the simulator test rig can also be used to investigate for any other parameters and products such as radiator performance and electric pump before installation in the actual engine cooling system. From the experiment conducted to simulate for the performance of a cooling system of a Proton Wira (4G15), the maximum power equals to 37 W which indicates the efficiency of the pump is relatively too low as compared to the typical power consume by the pump from the engine which are about 1 to 2 kW. Whereas the maximum power and efficiency obtained from the simulator test rig simulator is equals to 42 W and 15% respectively.

High global energy demand scenario has driven towards transformation from sole dependence on fossil fuels to utilization of inexhaustible renewable energy sources such as hydro, biomass, solar and wind. Renewable energy sources are abundant in Malaysia, especially palm biomass residues that are produced during the oil extraction process of fresh fruit bunch. Therefore, it is inevitable to harness these bioenergy sources, in order to prevent waste accumulation at adjacent to palm mills. Briquetting of palm biomass such as empty fruit bunch (EFB) with polyethylene (PE) plastics waste addition is expected not only could maximize the utilization of energy resources, but also could become as a potential solution for residue and municipal plastics waste disposal. In the present study, the physical and combustion properties of palm biomass briquettes that contain novel mixture of pulverized EFB and PE plastics waste were investigated experimentally. The briquettes were produced with different mixing ratio of EFB and PE plastics (weight ratios of 95:5, 90:10 and 85:15), under various heating temperatures (130-190 ) and at constant compaction pressure of 7 MPa. Based on the results, it can be said that heating temperature plays a significant role in affecting physical properties such as relaxed density and compressive strength. The values of relaxed density and compressive strength are within the range of 1100 to 1300 kg/m3 and 0.8 to 1.2 MPa, respectively. Meanwhile, mixing ratio does affect relaxed density and gross calorific value. All values of gross calorific (17900 to 21000 kJ/kg) and moisture content (7% to 9%) are found to fulfill the requirement for commercialization as stated by DIN51731 (gross calorific value>17500 kJ/kg and moisture content

The climate change has driven towards transformation from the high energy dependence on fossil fuel to inexhaustible renewable energy such as solar, wind, mini hydro and biomass. In Malaysia, abundant of palm biomass residues are produced during the processing of fresh fruit bunch. Therefore it is inevitable to harness these bioenergy sources in order to prevent waste accumulation at adjacent to palm mills. In order to utilize such bioenergy sources and to cope with the fast growing demand of energy, combination technique of densification and torrefaction is one of the potential ways to be practised. In the present study, the physical and combustion properties of torrefied empty fruit bunch (EFB) briquettes were investigated experimentally with constant nitrogen flow rate of 1 l/min , for various torrefaction temperatures (225-300). Before torrefaction process, EFB briquettes were initially produced under controlled condition with compaction pressure of 7 MPa and briquetting temperature of 150. In general, the torrefied EFB briquettes were successfully produced in the present study. The results show that an increase in torrefaction temperature from 225 to 300 causes a significant increase in gross calorific value (from around 17400 kJ/kg to 25000 kJ/kg), fixed carbon content (from 16.2% to 46.2%) and ash content (from 2.4% to 17.2%). On the other hand, relaxed density and volatile matter decrease, from 1017 kg/m3 to 590 kg/m3 and from 73.1% to 29.7%, respectively. As a conclusion, the gross calorific value and fixed carbon content are improved due to torrefaction. In addition, it was found that gross calorific value and moisture content of the torrefied EFB briquettes fulfil the requirement for commercial briquette production as stated by DIN51731 (gross calorific value>17500 kJ/kg and moisture content

Due to the tremendous amount of palm biomass residues produced during the palm oil extraction from fresh fruit bunch (FFB), it is inevitable to harness these biomass energy sources to cope with the depletion of fossil fuels and increase in global energy demand scenarios. Densification is one of the favourable techniques to improve the storage and transportation of biomass fuels in order to prevent dumped areas adjacent to palm mills and to prevent from becoming another waste product. This article reviews comprehensively on how type of palm biomass, compaction pressure and temperature, binder, pre- and post-treatments affect the physical and combustion properties of the palm biomass briquettes produced. Based on the previous researches, generally it can be said that the type of palm biomass, the compaction pressure and temperature, and type of binder affect both the physical and combustion performance of densified palm biomass. However, the effect of particle size could be observed only on the physical characteristics of densified products, whereas the effect on the combustion properties remains unclear. In addition, treatments such as pyrolysis, dry and wet torrefaction (hydrothermal treatment), and steam explosion have potential to be applied during briquette production in order to improve the combustion properties. In this review article, it is also suggested that the combination of densification and followed by wet torrefaction will enhance the combustion properties of palm biomass briquettes.

The appearance of electric field and shear dependent viscosity change in dielectric nanofluids provide potential for prospective applications especially in enhanced oil recovery. When nanofluids are activated by an applied electric field, it behaves as a non-Newtonian fluid under electrorheological effect, where the augment of electric field intensity increases the interaction among nanoparticles. Hence the mobility of the fluid can be efficiently controlled by regulating the applied field. Electrorheological characteristics of ZnO and Al2O3 nanofluids with various nanoparticles concentration (0.1, 0.05, 0.01 wt%) were measured. Results show that all the nanofluids exhibit pseudoplastic (shear thinning) behavior, while the electric field causes a visible increase in viscosity at a high shear rate. From the experimental results, it is also explained how the polarization of induced dipoles affects the electrorheology of nanofluids, by creating chains that align with the applied electric field. This paper also describes the designing and experimental aspects of the electromagnetic system, to investigate the change in viscosity of nanofluids.

Islamic garden is a place for rest and reflection, and a reminder to paradise. The themes of an Islamic garden are shade and water element. The Islamic Gardens are influenced by the historic Islamic Garden that majority fromSpain,Iran, and MughalIndia. Those are among the recognized gardens design during Islamic Civilization and remain as a legacy of the influential era of Islamic rulers. However the gardens have different culture influences that make each of the gardens are different in their design. This paper is to analyzing the features used in the garden design ofMughalGarden: Taj Mahal,Agra,India. The study used a content analysis and observation of features used in the design for the garden. The outcome of this study will enhance the understanding and appreciation towards Islamic garden design as an Islamic cultural heritage for the next generation.

The aim of the research is to explore the potential of fern species as natural ecological indicator agent to forecast microclimate changes in the urban area. Ferns which also known as pteridophyte are not only valuable in term of its ethno-botanical uses such as food and medicine but also useful in ecological values. Other than that it can be used to treat unhealthy environment such as absorbing methane gas, fertilizing land and treating heavy metal such as arsenic as well as can be used as a potential ecological indicator agent for microclimate changes. In this research, observation and measurement were made at two different environments which are natural environments; Gunung Jerai, Kedah and Lata Jarum, Pahang and manmade setting environments; Hospital Serdang, Serdang and Secret Garden, Kuala Lumpur. Interestingly results from two case studies of natural environments indicated that the distribution and abundance of fern species strongly influenced by differences in altitude. Twelve fern species were found at different elevations at Gunung Jerai, Kedah whereas 20 fern species were found at Lata Jarum, Pahang. Among the species found at Gunung Jerai were Selaginella willdenowii, Arcypteris irregularis, Adiantum caudatum, Pityrogramma calomelanos, Histiopteris stipulacea, Athyrium cordifolium, Osmund wachellii, and Cyathea contaminans. Whereas the species found at Lata Jarum are Dicranopteris linearis, Phymatodes scolopendria, Antrophyum callifolium, Arcypteris irregularis, Phymatodes crustachea, Selaginella willdenowi, Angiopteris evecta and Aglaomorpha heraclea. Another factor that influences the occurrences of the fern species is microclimate particularly atmospheric factor. Results observed from both case studies showed that light intensity, relative humidity and temperature also influenced the distribution of fern species. Therefore fern species are excellent ecological indicator which can be used as phytoindicator for unhealthy environment such as harsh environment or to predict microclimate changes at urban area.

A method of computing the optimum element distance position of multi-objectives adaptive linear antenna arrays (MLAA) is developed by taking several objectives (eg. adaptive capability, beamwidth and minimum sidelobe level (SLL)) into consideration. In this paper, the recently invented algorithm, known as Speedy-Particle Swarm Optimization (SpPSO) algorithm is adopted to optimize the distance between the MLAA elements. Different numerical examples of 8- and 12-element MLAA are presented to validate and illustrate the capability of SpPSO for pattern synthesis with a prescribed adaptive angle, controllable beamwidth and minimum SLL. It was found that by employing SpPSO method, the results provide considerable improvement over the conventional array. It is observed that the maximum normalized SLL of -12.27 dB has been achieved by using SpPSO for 8-element MLAA. The proposed SpPSO-based LAA also able to achieve a beampattern with sufficiently low sidelobes for 12-element MLAA by having maximum SLL of -16.46 dB, a desired wider FNBW of 50° and main beam that is pointing to 20°.

The physical and combustion characteristics of binderless palm biomass briquettes were investigated experimentally for various particle sizes and heating temperatures (150-210 ). In this study, empty fruit bunch (EFB) fibres were used as a raw material. They were grounded and sieved into three different sizes; i)

There are many technologies that being developed to increase the efficiency of internal combustion engines as well as reducing their fuel consumption. In this paper, the main area of focus is on cylinder deactivation (CDA) technology. CDA is mostly being applied on multi cylinders engines. CDA has the advantage to improve fuel consumption by reducing pumping losses at part load engine conditions. Here, the application of CDA on 1.6L four cylinders gasoline engine is studied. One-dimensional (1D) engine modeling work is performed to investigate the effect of intake valve strategy on engine performance with CDA. 1D engine model is constructed based on the 1.6L actual engine geometries. The model is simulated at various engine speeds at full load conditions. The simulated results show that the constructed model is well correlated to measured data. This correlated model is then used to investigate the CDA application at part load conditions. Also, the effects on the in-cylinder combustion as well as pumping losses are presented. The study shows that the effect of intake valve strategy is very significant on engine performance. Pumping losses is found to be reduced, thus improve fuel consumption and engine efficiency.

This manuscript presents a PI controller implementation to control the compressor speed of an air conditioning system based on cooling load to fulfill thermal comfort requirements with higher energy efficiency. Hence, an interface was designed to monitor the experiment, including the controller algorithm. The temperature settings of the conditioned space were 20, 22, and 24oC with internal heat loads of 0 and 1000 W. The experiments conducted indicated that the proposed technique had better temperature control and energy efficiency compared to the thermostat controller.

Compressed air from a turbocharger needs to be cooled down to prevent knocking inside the combustion chamber from occurring. In the present study, air to water intercooler is used as a heat exchanger to minimize the temperature rise of the charged air produced from the turbocharger i.e. water is used as the medium for cooling the temperature of the charged air before the intake manifold instead of using direct air, which is the common medium of any intercooling system. The experiments were conducted with engine speeds of 2000, 2500, 3000, 3500, 4000, 4500 and 5000 rpm, with pressure of 0.6, 0.8 and 1.0 bar. The present study found that the air to water intercooler is more efficient and the heat transfer is much better than that of the air to air intercooler. This is due to the air flow to the water inside the intercooler is better compared to the system that uses an air to air intercooler system.

An 1892.4 nm ultrafast passive Q-switched fiber laser is demonstrated by using Thulium-doped fiber (TDF) in conjunction with a multi-walled carbon nanotubes (MWCNTs) as a saturable absorber (SA). The MWCNTs film is sandwiched between two FC/PC fiber connectors and integrated into the laser cavity with 802 nm pump for Q-switching pulse generation. The pulse repetition rate can be tuned from 3.8 to 4.6 kHz while the corresponding pulse width reduces from 22.1 to 18.4 μs as the pump power is increased from 187.3 to 194.2 mW. A higher performance Q-switched Thulium-doped fiber laser (TDFL) is expected to be achieved with the optimization of the MWCNT-SA saturable absorber and laser cavity.

Cognitive radio wireless mesh network (CRWMN) is expected as an upcoming technology with the potential advantages of both cognitive radio (CR) and the wireless mesh networks (WMN). In CRWMN, co-channel interference is one of the key limiting factors that affect the reception capabilities of the client and reduce the achievable transmission rate. Furthermore, it increases the frame loss rate and results in underutilization of resources. To maximize the performance of such networks, interference related issues need to be considered. Channel assignment (CA) is one of the key techniques to overcome the performance degradation of a network caused by the interferences. To counter the interference issues, we propose a novel CA technique which is based on link capacity, primary user activity and secondary user activity. These three parameters are fed to the proposed weightage decision engine to get the weight for each of the stated parameters. Thus, the link capacity based channel assignment (LCCA) algorithm is based on the weightage decision engine. The end-to-end delay, packet delivery ratio and the throughput is used to estimate the performance of the proposed algorithm. The numerical results demonstrate that the proposed algorithm is closer to the optimum resource utilization.

Recently, technological advance in Android application has grown rapidly especially in health care application along with the development of smartphone. The utilization of wireless sensor networks with the mobile wireless health devices has provided us with an alternative solution in health monitoring instead of using the traditional approach with higher cost. Therefore, the objective of this project is to develop and implement a training monitoring system for cyclist based on android application. In this system, wireless sensor nodes are assigned to collect the required data such as cyclist’s heart rate and cadence. All the data are then sent to the mobile device used by cyclist via wireless communication. The data collected are first stored in device’s internal memory before they are transferred to the server. This project involved programming of hardware using specific software such as Eclipse Juno Android SDK and SQLite database. The system also includes the graphical user interface (GUI) design using Java language for application on smartphone. In addition, the simple Dropbox command is used to design the server for data storage. All the stages of implementations are integrated in one whole system and can be run as an application by cyclist. The developed system is proven to be cost effective and reliable as well as easy for customization.

Hierarchical clustering is an unsupervised technique, which is a common approach to study protein and gene expression data. In clustering, the patterns of expression of different genes are grouped into distinct clusters, in which the genes in the same cluster are assumed potential to be functionally related or to be influenced by a common upstream factor. Although the use of clustering methods has rapidly become one of the standard computational approaches in the literature of microarray gene expression data analysis, the uncertainty in the results obtained is still bothersome. Experimental repetitions are generally performed to overcome the drawbacks of biological variability and technical variability. In this study, the author proposes repeated measurement to evaluate the stability of gene clusters. This paper aims to prove that the stability from the gene clusters, incorporated with repeated measurement, can be used for further analysis.

The design of Medium Access Control (MAC) layer in Wireless Sensor Network (WSN) is very important because it gives significant impact in network performance especially in term of energy consuming. Contention Access method which is Carrier Sense Multiple Access (CSMA) will encounter collision problem when more than one node want to access the network simultaneously. Meanwhile, the issue in slotted access which is Time Division Multiple Access (TDMA) is channel utilization when the usage of the slot is neglected and wasted in transmission network. In this paper, we propose a hybrid MAC that combines both strengths of CSMA and TDMA in one protocol while avoiding their weaknesses to improve the network performance. The simple and efficient transmission in CSMA method will be used in neighbor discovery (ND) and slot allocation (SA) process. For data transmission, non collision transmission method which is TDMA will be used and it will be changed to CSMA depending on the contention level of the channel. This proposed protocol is suitable for priority application usage where the important information will arrived at the destination in acceptable delay time.