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This paper describes simulation of combustion characteristics under high ambient and high injection of biodiesel combustion by using CFD simulation. Diesel engine performance and emissions is strongly couple with fuel atomization and spray processes, which in turn are strongly influenced by injector flow dynamics. The principal objective of this research is to seek the effect of temperature and pressure on the spray characteristics, as well as fuel-air mixing characteristics. Experiments were performed in a constant volume chamber at specified ambient gas temperature and pressure. This research was continued with injecting diesel fuel into the chamber using a Bosch common rail system. Direct photography technique with a digital camera was used to clarify the real images of spray pattern, liquid length and vapor penetration. The method of the simulation of real phenomenon of diesel combustion with optical access rapid compression machine is also reviewed and experimental results are presented. The liquid phase of the spray reaches a maximum penetration distance soon after the start of injection, while the vapor phase of the spray continues to penetrate downstream. The condition to which the fuel is affected was estimated by combining information on the block temperature, ambient temperature and photographs of the spray. The increases in ambient pressure inside the chamber resulting in gain of spray area and wider spray angle. Thus predominantly promotes for a better fuel-air mixing. All of the experiments will be conducted and run by using CFD. The simulation will show in the form of images.

In recent years, there have been a number of interests on the Palm Oil (PO) and Coconut Oil (CO) as a potential alternative dielectric insulating fluid in transformers which stimulate different types of studies on these oils properties. Among the important studies is the lightning impulse properties. This paper presents the investigation on the lightning impulse breakdown voltage of PO and CO under non-uniform electric field. The PO used in this study is Refined, Bleached and Deodorized Palm Oil (RBDPO) Olein type. The influence of the testing methods, rising-voltage and up-and-down are investigated at 2 gap distances for both oils. It was found that the lightning breakdown voltage performance for some of the RBDPO and CO are comparable to MO.

This research studied the electricity production from organic wastes fermentation by microbial fuel cell by using a single chamber microbial fuel cell (SCMFC). Two sizes (1 L and 10 L) of simple SCMFC were fabricated by using a cylindrical plastic tank which anode compartment and cathode compartment separated by plastic plate with hole and covered with cotton fabric. The anode electrode contacted with organic matter and microorganisms where anaerobic reaction occurred to generate electron and proton. The electrons transferred through an external circuit while the protons diffused through the solution to the cathode electrode for reducing oxygen to water. From the study of the effect of different electrode types (carbon graphite rod, zinc metal, and copper metal) to the electricity generation using the SCMFC size 1 L in fermentation with synthetic sweetness solution (22%Brix) and the effective microorganism (EM) for 36 hrs, it found that the fuel cell which used copper metal as electrode produced electricity increasing over the times and has more efficient than the other electrode types. The study of electricity generation from organic waste fermentation by using the SCMFC size 10 L and using copper metal as electrode, the results showed that the fermentation of pineapple waste produced the current density, potential density, and power density higher than the fermentation of bananas and the fermentation of food garbage with EM. An optimal period of time for the production of electricity from this microbial fuel cell is the first five days of fermentation that the cells has voltage »500 mV, the current density 25.52 mA m-2, potential density 104.69 V m-2 and power density 12.59 mW m-2, and then decline over time five days (120 hrs). Moreover the bio-liquid fertilizer and the residues from the fermentation can be further used in agricultural because of the nutrient content (N, P, K), organic carbon and organic material contents available.

The process of combustion in coal fired power plant generates ashes, namely fly ash (FA) and bottom ash (BA). In addition, coal ash generated from coal combustion generally contains heavy metals within their compositions. These metals are toxic to the environment as well as to the human health. Fortunately, treatment methods are available for these ashes and the use of FA and BA in concrete mix is one of the few. As such, this study presents the work in determining the leachability of self-compacting concrete (SCC) incorporated with FA and BA. The ashes were obtained from Kapar Energy Ventures power plant in Kapar, Selangor. SCC mixtures incorporated with 10%, 20% and 30% FA (replacing cement) and BA (replacing sand) respectively was formulated and casted. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure (TCLP) and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry (AAS). From the results, it was found that incorporation up to 30% of the ashes were safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic (As). On the other hand, incorporation of 20% FA and BA each in SCC provided the most economically viable product, with high strength and low leachate concentrations. In conclusion, this study will serve as a reference which suggests that FA and BA are widely applicable in concrete technology and its incorporation in SCC constitutes a potential means of adding value with appropriate mix and design.

Amid the fierce rising competition in the market, accelerating the problem solving and decision making process have become major issues in product design especially in conceptual design stage. For years, Theory of Inventive Problem Solving (TRIZ) has been extensively applied in problem solving. In this paper, Analytical Hierarchy Process (AHP) was proposed to strengthen three major steps in TRIZ methodology namely as problem definition, root cause identification and solution generation. The integration was then structured in the form of computer-based system. The integration, application and software in AHP and TRIZ method have been discussed in this paper. This proposed support system not only provided evidence that TRIZ methodologies improved by the support of AHP and also aided the designers in early design phase such as concept, process and material selection.

Retracted paper: Galvanic coupling method has been observed to be the best method for data transmission in intra-body communication, which is proposed by Zimmerman in 1995. With the increasing transmission requirements and the development of optical fiber communication, a high speed data transmission system is required and it is possible to design an apparatus to realize the electro optic conversion. In this paper, the characteristics of the intra-body communication system are introduced. Principles and structures of the electro-optic modulation methods for intra-body communication are reviewed. Internal and external modulation methods are introduced and discussed. A system of the electro-optic and acousto-optic modulation are recommended for the intra-body communication system and discussed.

Retracted paper: Intra-body communication is proposed by Zimmerman in 1995 and the galvanic coupling has been observed to be the best method for data transmission. With the increasing transmission requirements and the development of optical fiber communication, a high speed system is possible to be designed based on the Electro optic methods. In this paper, the characteristics of the intra-body communication system are introduced. Principles and structures of optic modulation for intra-body communication are reviewed. Internal and external modulation methods are introduced and discussed. A system of the electro optic modulation is recommended and discussed.

In this paper, we address the transmit angle and receive angle estimation problem for a bistatic multiple-input multiple-output (MIMO) radar. This paper links MIMO radar angle estimation problem to the compressed sensing trilinear model. Exploiting this link, it derives a compressed sensing trilinear model-based angle estimation algorithm, which can obtain automatically paired two-dimensional angle estimation. The proposed algorithm requires no spectral peak searching or pair matching, and it has better angle estimation performance than conventional algorithms including estimation of signal parameters via rotational invariance techniques (ESPRIT) algorithm. Simulation results illustrate performance of the algorithm.

Retracted paper: InGaN with high InN molar fraction is a promising material for next generation optoelectronic devices and electronic devices such as solar cells, laser diodes for communications, and high mobility transistors and so on. However, the growth of InGaN with high InN molar fraction is still a tough challenge for metal organic chemical vapor deposition (MOCVD). This paper provides experimental clues for the key factors, including the influences of the growth temperature, the V/III ratio, the group III supply ratio, and the reactor pressure. In addition, the effectiveness of the pressurized MOCVD growth of the InGaN with high InN molar fraction will be testified.

The paper propose a design of the local data transmission between human body physiological parameters acquisition terminal and local intelligent monitoring terminal based on the wireless transmission technique of Zigbee and Bluetooth. In order to realize the remote transmission between Local medical monitoring terminal and remote intelligent monitoring terminal, the paper give network solutions for distal doctors to provide remote treatment. The program of monitoring terminal introduces the data processing mechanism Handler and class AsyncTask to ensure the reliability and accuracy of the data, and this can also reduce the complexity of algorithm.

Selective Laser Sintering (SLS) has recently become one of the fastest growing additive manufacturing processes due to its capability of fabricating metal parts with high dimensional accuracy and surface quality. Physical modeling of this process plays an important role in properly controlling the process parameters of the process. In this paper, we present a 3 dimensional, adaptive discrete element method for simulation of the SLS process on personal computers. The presented method models the laser-powder interaction at particle level, achieving high simulation accuracy while adaptively increasing the discrete element size as local temperatures drop inside the powder bed for improved efficiency. Numerical shape functions are developed for calculating individual particle temperatures at any point during the simulation. Results show that this physical model improves the runtime significantly in virtual simulation of SLS process without loss of simulation accuracy.

Magnetorheological elastomer (MRE) base isolator is a semi-active control device which has currently obtained increasing attention in the field of vibration control of civil structures. However, the inherent nonlinear and hysteretic response of the device is regarded as a challenge aspect for using the smart device to realize the high performance. Therefore, an accurate and robust model is essential to make full use of these unique features for its engineering applications. In this paper, to solve this issue, adaptive neuro-fuzzy inference system (ANFIS) is utilized to characterize the dynamic behavior of the device. In this proposed model, the inputs are historical displacements and applied current of the device while the output is the shear force generated. To validate its forecast performance, the ANFIS model is also compared with some conventional models. Finally, the result verifies that ANFIS has the best perfection ability among existing MRE-based device models.

This paper introduces a methodology for the type synthesis of two degree-of-freedom hybrid translational manipulators with identical legs. The type synthesis method is based upon the screw theory. Three types of two degree-of-freedom hybrid translational manipulators with identical legs are identified based upon their wrench decomposition. Each leg of the manipulators is composed of a proximal module and a distal module mounted in series. The assembly conditions and the validity of the actuation scheme are also defined. Eventually, some novel two degree-of-freedom hybrid translational manipulators are synthesized with the proposed procedure.

A number of studies have been carried out previously to investigate the suitability of palm oil as dielectric insulation fluid in transformers. Among the important studies is the ageing performance of palm oil. In this paper, a study was carried out to investigate the dielectric properties of Refined Bleached and Deodorized (RBDPO) Olein after subjected to thermal ageing. A low temperature ageing was carried out at 85°C for 5 days. The AC breakdown voltage, dielectric dissipation factor, relative permittivity and resistivity of RBDPO were examined throughout the ageing duration. It was found that the RBDPO performs reasonably well under low temperature ageing.

The properties of Palm Oil (PO) and Coconut Oil (CO) offer the potential for transformers with non-toxicity, high fire and flash points and better environmental compatibility while compared with those filled with Mineral Oil (MO). This potential has led to intensive studies of electrical performance of biodegradable oil especially in evaluating the electrical performance under lightning impulse voltage in recent years. This paper presents the investigation on the impulse breakdown voltage of PO and CO in such a uniform field. The PO used in this study is Refined, Bleached and Deodorized Palm Oil (RBDPO) Olein type. Two testing methods, rising-voltage and up-and-down are considered for both oils with different gap distances (2.0 mm and 3.8 mm). Testing methods including rising-voltage method and up-and-down method have no notable influence on the breakdown voltages of RBDPOs and CO compared to MO.

The optimal capacitor placement problem involves determination on the type, number, location and size of capacitors to be placed in a distribution system for the attainment of energy efficiency. The main objectives of the capacitors placement and sizing are to reduce total line loss and energy consumption while satisfying the operational constraints. This paper presents the optimal capacitor placement and sizing problems solved by using the Ant Colony Optimization (ACO) technique with the integrated of circuitry unbalanced electrical distribution modeled in SIMULINK®MATLAB®software. The proposed technique was tested on a modified IEEE 13-bus unbalanced radial distribution system and the results revealed that the proposed technique has the merit in achieving optimal solution for addressing the problems.

This paper reports the influence of light exposure (photodynamic) and magnetic field application on viability activation of anaerobic photosynthetic bacteria (rhodobacter sphaeroides). For photosynthetic process, the rhodobacter sphaeroides have bacteriochlorophyll and carotenoid as major and accessory pigments, respectively. A customized equipment was developed for investigating the effect of light and magnetic field applications on the growth of the bacterial colonies. It was consisted of three main parts, namely a sample holder, an array of light emitting diode (LED) as light source and Helmholtz coils as magnetic field source. The systems of this equipment were controlled by a microntroller of AVR ATMega-8535. Prior to the application in vitro, all LEDs were calibrated, both their intensity and wavelength. After the treatments, all bacteria substances were grown in photosynthetic media (PMS) for 48 hours followed by calculating the number bacterial colonies growth using a total plate count (TPC) method and Quebec colony counter. It was found that the growths of bacterial colonies were influenced by both light intensity and wavelength of LED array. At the same intensities, the wavelength of 430 nm showed highest effect on the growth of bacterial colonies. In addition, upon application of the optimum light combined with magnetic field, the highest growth of bacterial colonies was achieved more than 110% when the optimized light source of energy dose was 204 J/cm2 and magnetic field was 1.8 mT.

Application of axiomatic design (AD) for the purpose of enhancing end-of-life recovery potential of a product has been the main focus of this paper. To demonstrate the usage of AD in this particular area, a case study that involves keypad assemblies of mobile phones is presented. The functional requirements (FR) of the two assemblies were defined differently (only Handset 2 involves refurbishment-related FRs). Using evaluation approach presented by Kwak and Kim (2010), it can be observed that when recovery-related requirements are omitted, application of AD produces a keypad assembly that fulfills the FRs derived from customer needs with more complicated product architecture. In contrast, when recovery-related FRs are included during problem definition using axiomatic approach, the disassemblability of the resulted keypad is improved and thus increasing recovery potential in the event of replacing defective keypad, while satisfying product-related FRs.

This paper presents of Polymer Matrix Composite (PMC) as feedstock used in Fused Deposition Modelling (FDM) machine. This study discussed on the development of a new PMC material by the injection molding machine. The material consist of copper powder filled in an acrylonitrile butadiene styrene (ABS), binder and surfactant material. The effect of metal filled in ABS and binder content was investigated experimentally by the Melt Flow Index (MFI) machine. Based on the result obtained, an increment of copper filled in ABS by volume percentage (vol. %) effected on melt flow index results. With highly filled copper in PMC composites increase the melt flow index results. It was concluded that, the propensity of the melt flow allow an internal force in PMC material through the injection molding and FDM machine.

This study deals with a master-slave system for a tele-operated electro-hydraulic actuator (T-EHA) that focuses on a hydraulic system to remotely control a mini excavator. Tele-operation using such system is useful for tele-operation support of heavy construction and road restoration, typically in post-disaster areas. This paper presents the current development of position control electro-hydraulic actuator for such remote tele-operation application. A 2.4 GHz radio-controlled transmitter and receiver unit, which is also known as the master, has been utilized as the remote controller for an electro-hydraulic actuator. The electro-hydraulic actuator, which serves as the slave has been fabricated by using a tie-rod cylinder, and coupled with a 24 VDC electro-hydraulic valve. Position control mathematical modelling and operational evaluation have been studied with regard to the tele-operated electro-hydraulic actuator.

In this paper, an experimental study evaluating the effect of exhaust gas recirculation (EGR) and liquefied petroleum gas (LPG) onboard systems attached to a single cylinder DI diesel engine running with diesel is presented. Tests were performed at the minimum (1400 rpm) and maximum engine speeds (4100 rpm). The engine were tested under four different operating modes mainly; (a) standard test condition, (b) engine with EGR system, (c) engine with LPG system and (d) the engine with EGR and LPG onboard systems. Parameters that been measured during the tests are percentage of oxygen (O2) content, carbon monoxide (CO) emissions, carbon dioxide (CO2) and unburned hydrocarbon (UHC) emissions. Results show for the exhaust emissions, the engine with LPG onboard system emits higher CO and UHC emissions for both engine speeds. According to the experimental results it can be concluded that the use of EGR system increased the exhaust gas temperature and CO2emissions. While the engine with EGR and LPG onboard systems have influenced much on the increase in CO and UHC emissions for both engine speeds.

Blade fault is one of the most causes of failure in turbo machinery. This paper discussed the time frequency analysis for blade rubbing detection from casing vibration signal. Feasibility of Short Time Fourier Transform (STFT), Wigner-Ville distribution (WVD) and Choi-Williams distribution (CWD) were examined for blade rub detection in a multi stage blade system through an experimental data. Analysis results of the experimental data showed that these time frequency analysis methods have some inevitable deficiencies in segregating the blade passing frequency (BPF) components of the three rotor stage signals. However, CWD demonstrated a better time-frequency resolution in analyzing the multi stage rotor system signal.

This paper discusses a finite element analysis of cylinder on flat contact configuration subjected to constant normal load and reciprocating tangential displacement with linear kinematic hardening models based on bi-modal Ti-6Al-4V cyclic stress-strain curves. The predicted evolution of plastic deformation such as the equivalent plastic strain, tangential plastic strain and shear plastic strain distributions on the contact region has been studied along with its respective predicted stress distributions. The effect of applied forward and backward sliding displacement movements on predicted stress and strain distributions have also been looked at. It is found that the stress distributions predicted for kinematic hardening model is similar for forward and backward movements while the predicted plastic strain distribution is increasing with reciprocating sliding movement. The predicted value keep increasing when it moves forward, backward and finally moves forward again. This is due to large strain effect of the model and its dependant on the displacement movement amount.

A hydroxyapatite is known as one of vital materials and common use in biomedical field and concentrated in clinical area. In relation to the above, the development of hydroxyapatite powder becomes an attractive research lines due to simplify in produce it. Thus in this paper the researcher stress out about Hydroxyapatite powder gained from the natural sources or so called as the waste of Tilapia bone and scales. The raw bones of and scale were undergo to crushing process to form in powder size (0.2 mm) then analysed by X-ray Diffraction (XRD) to identified the mineralogy of raw bone. Moreover the powder of fish bone and scales also go through to Scanning Electron Microscope (SEM) machine to analyse the microstructure of the powder while EDS act as device to determine the chemical composition of the sample powder. Sample powder then forward calcination process at selected temperature range to as a cheaper method in obtained hydroxyapatite raw sources. The range of calcination temperatures are between 800°C to 1000 °C. The sample preparation were analysed in both condition before and after calcination process by using XRD, SEM and EDS. The HAP crystalline composition of tilapia bones for raw powder and at 800 °C are similar with HAP pattern (JDS 00-009-0432) and the chemical reaction is Ca5(PO4)3(OH) then at temperature 900 and 1000 similar to HAP pattern (JDS 00-055-0592) with chemical reaction equal to Ca10(PO4)6(OH)2.

Research and development on hybrid excitation flux switching machines (HEFSM) for various applications have been carried out in the last years. The designed HEFSM consist of permanent magnet (PM) and DC field excitation coil (DC-FEC) which is located on the stator core as their main flux sources, while a single piece rotor gives the advantages of robust rotor structure. Since most of the designed HEFSMs utilize three-phase windings, more complicated design and control system are required to run the motor. Thus, a new design of single-phase E-Core HEFSM with several advantages of much simpler converter size and smaller battery package due to small voltage capacity when compared with conventional three-phase system is proposed. Consequently, the size of overall configuration systems will also be reduced resulting in reducing total weight and cost. In this paper, initial performances of 4S-4P, 4S-6P, 4S-8P and 4S-10P E-Core HEFSM topologies are analysed. Since 4S-10P design gives highest torque and power performances, deterministic design optimization approach is conducted to enhance much higher and optimum performances. As conclusion, the optimized E-core HEFSM with 4S-10P topology has achieved maximum torque and power of 208.857Nm and 47.31 kW, respectively.

The fuel-air mixing during burning process provides significant effects to the fuel atomization and flame development thus predominantly influences to the behavior of particulate matter (PM) and NOx production. The variant in fuel injection characteristics are widely used in the field of burner system nowadays. Spray nozzles having various operating conditions dependedon the design of nozzle and it was precision components designed to perform very specific spray characteristics under specific conditions. This review paper focuses on spray characteristics, effects of geometry of injector, influence of fuel and hole shaped nozzle with cylindrical and conical holes on spray characteristics. The parameters are discussed based on an overview of the research in the field of simulations with nozzle shaped injectors. Massive researchers had reported that conical nozzle hole is better than cylindrical nozzle due to it contributed suppression of cavitation in nozzle hole, slowed down primary breakup process and thus produced larger spray droplets, high spray

This paper presents the melt flow index (MFI) of acrylonitrile butadiene styrene (ABS) and recycle ABS filament wire for Fused Deposition Modeling (FDM) machine. In this study, the effect of MFI on recycle ABS material was investigated experimentally based on the melting temperature, density, screw speed and material properties. The MFI result on ABS recycle in wire filament was investigated using Melt Indexer Machine (MIM). Based on the result obtained, it was found that, ABS recycle was increase the density and MFI results. It can be observed that, the higher temperature was melt the recycle ABS material through the MIM and extruder machine.

This paper investigates the performance of rice husk ash (RHA) in a fine grained mortar. RHA produced from control combustion of rice husk. Fine grained mortar (FGM) is a mortar containing fine sand with a maximum size of 1mm. Chemical composition of RHA and Ordinary Portland Cement (OPC) were investigated using XRF in order to know the silica content in these materials. The particle size of RHA was analyzed to make sure it fineness is same with OPC after grinding. Compressive and flexural strength of FGM were tested on mortar prism for size 40mm x 40mm x 160mm with replacement of RHA 10%, 20% and 30% by weight of cement at 7 days and 28 days ofcuring. All 24 specimens of FGM were caste and tested. The flexural strength, compressive strength of FGM have shown quite encouraging and interesting results. The optimum replacement of RHA in FGM from compressive and flexural strength is 20% by weight of cement.

Flux switching machine (FSMs) with several advantages of robust rotor structure, high reliability, high efficiency and high torque density have been develop in recent years. Among several types of FSM, HEFSM gives extra advantage at variable flux capabilities suitable for higher load conditions. However, the developed C-Type has a problem of separated stator core which lead to difficulty in manufacturing design as well as flux leakage to the outer stator. In order to solve the problem, iron flux bridges have been introduced to the stator core. Because of that, the separated stator core becomes the single piece of core. In this paper, various topologies of iron flux bridges is introduced and overviewed. Performances of torque at various flux bridge is analyzed and compared. This analysis is verified by Finite Element Analysis (2D-FEA).

Understanding the interference of multi-bead parameters on surface smoothness is essential for accuracy of the formed parts made by welding rapid forming. This paper presents an investigation on surface smoothness of multi-bead aluminium alloys. Deposition path planning and overlap ratio is manipulated in order to improve surface smoothness. Observation on bead cross section indicates that deposition path planning has remarkable effect on the surface smoothness. Multi-bead that developed using continuous path planning has surface smoothness of 0.46 mm – 1.34 mm and most bead present wavy type surfaces. The surface smoothness is improved by increasing the overlap ratio. Meanwhile, skip path planning produced good surface smoothness of 0.11 mm – 0.28 mm. An improved surface smoothness featuring flat surface type is obtained with this path planning.

This paper studies the detection of twisted blade in a multi stages rotor system. Experimental study was undertaken to simulate twisted blade conditions in a three stages rotor system. The feasibility of vibration analysis as the technique to detect twisted blade based on the rotor operating frequency and its blade passing frequency was investigated in this study. Experimental results show that twisted blade can be easily detected by looking into the pattern of the vibration spectrum and its individual peaks.

Schlieren optical visualization technique system is the unique technique due to the ability in producing a neutral image easily-interpretable image of refractive-index-gradient areas. The Schlieren system provides a method for viewing the flow through the transparent media and the most using this technique is to photograph the flow. This paper presents the review of the application of the Schlieren optical visualization system external and internal combustion engine in order to observe the fuel-air mixing and flame development during the burning process. The basic technique of Schlieren system, especially for Z-type and two mirror Schlieren system provide a powerful and clearly image to visualize the changes of the density in a transparent medium. This method can capture spray evaporation, spray interference and mixture formation clearly with real images. Analysis of optical image visualization observations reveals that the mixture formation of fuel and air exhibits the influence of the ignition and flame development. Thus, the observation of systematic control of the creation of a mixture of experimental apparatus allows us to achieve significant progress in the combustion process and will present the information to understanding the basic terms of reduced fuel consumption and exhaust emissions.

Flux switching machines (FSMs), new type of electric machines with unique operating principles have been introduced and published recently. FSMs contain armature and excitation sources on the stator with robust rotor structure. According to rotor structure FSMs can be classified into two types namely salient pole rotor and segmental pole rotor. Various topologies have been studied and published using both rotor structures, however salient pole rotor has a demerit of less torque generation due to longer flux path resulting flux leakage surrounding the rotor. In this paper a new structure of hybrid excitation FSM (HEFSM) with segmental rotor is proposed and a comparative analysis with the invented field excitation FSM (FEFSM) and permanent magnet FSM (PMFSM) is presented. Initially, coil arrangement tests are examined to confirm the operating principle of HEFSM with segmental rotor. Moreover, the cogging torque, induced voltage, magnetic flux, torque at various armature current densities and power characteristics are observed based on 2D-finite element analysis (FEA).

Hybrid excitation flux switching machines (HEFSMs) have a several advantages such as robust rotor structure, high torque and power capabilities, and high efficiency suitable for light load and heavy industry applications. However, the general structure of HEFSMs employed with three main flux sources namely permanent magnet (PM), field excitation coil (FEC) and armature coil located on the stator body causes high manufacturing cost. Therefore, a new non-PM field excitation flux switching machine (FEFSM) consists of rugged rotor structure suitable for high-speed operation with capability to keep similar torque and power density of HEFSM is proposed and examined. In this paper, performances of both outer and inner rotor 12S-14P FEFSMs are analyzed and compared. As conclusion, the inner-rotor topology provides much higher torque and power when compared with outer rotor configuration.

On this journal, modeling relation of rotor speed and rotor diameter toward yarn tension on take-off nozzle has been validated by theoretical approach and numeric computation.It shows that value of yarn tension is F=(1,4.10-13)Tt nR2dR2[cN]. Excessively high spinning tension always results in an intolerable increase in yarn breakage. This paper presents a comparative study of theoretical and reference-based experimental result for predicting the actual strength of open-end spinning system.

This paper investigates the parameter optimization of a preheating method on stainless steel SUS304 prior to aluminium-stainless steel dissimilar welding. The welding method used was metal inert gas (MIG) with butt joint type weld. The Taguchi L9 orthogonal array was used to investigate the optimum parameter, while the mechanical strength was investigated using tensile test. Optimum levels of the process parameters were analyzed using the Taguchi parametric design approach. Parameter analysis of the tensile test results indicate that the preheated specimen with 90 °C have the maximum ultimate tensile strength of 111.27 MPa. This value is in close proximity to the calculated value of 109.02 MPa with 2% error. Through analysis of variance (ANOVA), the welding current was the dominant contributing factor with 40%. It can be concluded that the highest tensile value (111.27 MPa) for AA6061-SS304 dissimilar welding was obtained using 90 °C preheating, voltage of 17.5 V and current of 110 A of current.

The main objectives of this paper is to find the way for solving the problems of aluminum extrusion process, and improve the mechanical properties of the products through a smart design, modelling and simulation of this process by using finite element method (FEM). For the purpose to model a (2D) two dimensions warm aluminum extrusion process, ABAQUS software was used to set up the finite element simulation. The main parameters which have major effects on this process like extrusion stresses, temperature, and die geometry, i.e. extrusion radius, were taken into consideration. Aluminum alloy (Al-2014) was used as the billet material, with 40 mm diameter and 75 mm length. It is important to preheat the billet from the beginning to a specific temperature, and then pressurizes it into the die. This process is an isothermal process with an extrusion ratio of 3.3. Subsequently, the optimized algorithm for these extrusion parameters was suggested based on the simulation results. The results suggest that the large die angle needs a less extrusion load than the small die angle. In all die geometry used, the deformation of aluminum billet, which caused by shearing and compression stresses, happened in a small sectional area, i.e., bearing area. The results also showed that the values of these stresses can increase or decrease depends on the die entrance angle and the die bearing length. To avoid the effects of these stresses on die dimensions; the hardness, material selection, and geometry should be well calculated.

This paper investigates the potential of utilizing the undeveloped natural gas fields in Malaysia with high carbon dioxide (CO2) content ranging from 28 to 87%. For this experiment, various CO2 proportions by volume were added to pure natural gas as a way of simulating raw natural gas compositions in these fields. The experimental tests were carried out using a 4-stroke single cylinder spark ignition (SI) direct injection (DI) compressed natural gas (CNG) engine. The tests were carried out at 180°CA BTDC injection timing and 3000 rpm, to establish the effects on the engine performance. The findings revealed that the brake torque decreased by 9% with 20% CO2 proportion in the mixture due to the decrease in the heating value of the mixture. At the same proportion of CO2, the brake specific fuel consumption decreased by about 8.5% and the brake thermal efficiency increased by 9.2%. There was a reduction in the unburnt hydrocarbons (THC) and carbon monoxide (CO) emissions by 15% and 89% respectively, but the NOx emissions increased by 78%. The utilization of natural gas with 20% CO2 content as fuel in DI-CNG engine was found to be viable with insignificant drop in engine performance and with reductions in exhaust emissions.

This paper investigates the quasi static compression analysis behavior of a biocomposite radome using nonlinear static modeling. Bio-based fiber is proposed to be used in aircraft radome due to its low dielectric constant. In this instance, kenaf was being utilized as the natural fiber to form a hybrid combination of fiberglass/kenaf epoxy laminates. The quasi static behavior was modeled using MDNastran SOL106 Nonlinear Static. The radome was modeled as a hemispherical shell based on Beechcraft’s radome geometric configuration. The radome is designed as a four-layered laminates with randomly oriented fiberglass and kenaf. The nonlinear compression was performed in the range of 0.01 mm to 0.49 mm with a maximum reaction force of 189 N. The radome was not displaced equally or symmetrically as the translational load applied since the shape of radome is asymmetry and the surface at the top is uneven. The increment of the forces leads to elastic local flattening deformation at the apex of the radome. Its shape influences in determining the displacement and the stress to the radome.

One of the key challenges of designing low-cost Unmanned Aircraft Systems (UAS) is to ensure acceptable and certifiable reliability factors for the adopted Commercial-off-the-Shelf (COTS) components since their reliability is often not quantified. In this paper, the experimental results obtained for quantifying the reliability of mini Unmanned Aircraft (UA) servomotors (by recording their time-to-failure on a defined set of test runs) are presented. The Weibull prediction model is adopted for quantitative analysis and the associated key mathematical models. The methodology adopted for performing the reliability analysis including the test bench setup used for the experiments is described. The results indicate a level of reliability expected for low-cost servos. Such servos could be used for low-risk UAS operations (e.g. small UA operating over sparsely populated regions) and where the economics of the business case permitted higher loss rates.

In this paper the methods of static and dynamic analysis of the closing rotor balancing device of the multistage centrifugal pump are represented. On an example of the feed pump PE 600-300 static and dynamic characteristics are determined. Defined the resonance frequencies and investigated stability of the system “pump rotor – automatic balancing device – pressure difference regulator”. The dependence for the pressure difference and conditions to ensure reliable operation of the locking rotor balancing device are determined.

Remote controlled cars currently in the market only offer one transmission mode. They are less efficient in acceleration while the torque cannot be increase during the low speed. Although improvement has been made by upgrading to two speed transmissions, but the gearing system is still not sufficient to maximize the speed of nitro engine. With a third gear, the car has the potential to increase its velocity and fully utilize its engine power. This paper focus on the transmission system model for 1/10th scale nitro engine which can produce up to 30,000 rpm. The third gears has shown significant improvement of the car theoretical speed up to 210 km/h.

The paper presents a literature review of the efficacy of side passive safety in the event of lateral collision and the latest development of side airbag. According to the latest Global Status Report on Road Safety 2013, the total number of death every year due to road accident still maintained in a huge number of 1.24 million. Malaysia is one of the countries having highest estimated road traffic death rate of 25 per 100,000 populations. Moreover, 5% growth annually of fatalities rate forecasted. In general, lateral collision or side impact is the second most common vehicle crash type which takes almost 10,000 occupant deaths each year. Side airbags were introduced into vehicle firstly in 1995 in order to improve occupants injury. It is statically proven that combination of head with thorax side airbag is very effective in reducing occupants fatalities rate, however thorax only airbag is less significant. With the aid from Computer Aided Engineer (CAE) software, designer can further improve airbag design and optimize its performance in order to find the best combination of design parameter such as of area of air vent, Time-To-Fire (TTF), operating pressure of the inflator gas and many more, while design cycle time can be reduced significantly up to 40%. Nevertheless, people are afraid that side airbag deployment load may hurt children and small size female seated in Out-Of-Position (OOP). Researcher could resolve it by adopting the latest Computer Fluid Design (CFD) airbag simulation technique which have a better simulation result of OOP load, since CFD method provide more realistic airbag deployment simulations especially in the first few milliseconds which are significant in OOP test.

This paper presents the use of statistical-probabilistic method in determining pile bearing capacities over a number of driven piles. Four dynamic formulas were employed to estimate pile bearing capacity including modified ENR, Hiley, Navy – McKay and Danish. We investigated the final setting data of 47 concrete piles with 600 mm diameter in the construction projects of New Naval Engineering Building Hasanuddin University. Based on the data, pile bearing capacity were computed and then analyzed statistically. Goodness of fit with Kolmogorov-Smirnov and Shapiro-Wilk were used to fit the probability distribution function (PDF) of the pile bearing capacity data to the PDF model. It was found that the pile bearing capacity estimated using ENR is more uniform with 506 tons average pile capacity and 6.4% COV, while that with Hiley and Danish are less various with 252 tons and 346 tons average pile capacity, and 14.7% and 16.6% COV respectively. Navy-McKay was found to have 465.8 tons average pile capacity with higher variability of 44.08%. A 90% Probability of pile bearing capacity estimated by ENR is 535 tons, or 1.17 times the upper bound, and 1.4 times the lower bound of pile capacity measured by pile driving analyzer (PDA). In comparison, 90% probability estimated by Danish is 420 tons or 0.93 times and 0.92 of the upper and lower bound of pile capacity measured by PDA, respectively. The Navy-McKay seeems to be overestimated whereas Hiley is underestimated.

The main objective of this paper is to study the effect of extrusion parameters (extrusion stresses and temperature) and die geometry, i.e. extrusion radius, on the extruded aluminum quality using FEM Simulation Technique. For this purpose, the general FEA Software ABAQUS was used to set up the finite element model of the warm aluminum extrusion in two dimensions (2D). Aluminum alloy Al-2014 was used as billet material, with 40mm diameter and 75mm length. The extrusion process was modeled as isothermal, which means that the billet material was preheated at a specific temperature and then pressured into the circular die, with extrusion ratio 3.3. Optimized algorithms for extrusion parameters were proposed regarding the concluded simulating results. The results showed that small die angles required higher extrusion load than large die angles. In all die geometry used, the deformation of aluminum billet, which is caused by shearing and compression stresses, happened in a small sectional area (bearing area). The results also showed that, the values of these stresses can increase or decrease depending on the die entrance angle and the die bearing length. To avoid the effects of these stresses on die dimensions; the hardness, material selection, and geometry should be well calculated. An axis-symmetrical 2D geometric model of the tooling and billet was constructed for the analysis. Data obtained from the FE model included die-work piece contact pressure, effective stress and strain and material deformation velocity. The correlation between the calculated and FEA data was obtained in this research.

In this paper we present a brief comparison of existing equation of state laws used inSmoothed Particle Hydrodynamics (SPH) and introduce some new expressions for the equation ofstate for pressure, as well as to calculate temperature. In SPH literature practical examples of heatconduction and energy are scarce when compared with fluid flow formulations that determine pressuresimply from density and an artificial speed of sound. Such simplifications may be appropriate forisothermal flow problems; however, a more thermodynamically rigorous formulation is necessary forcomplex and thermally driven problems, particularly in geophysics. This work discusses conventionalequations of state, as well as presenting some new relations. This includes having pressure depend onthe energy of the system, and applying these relations to a number of proof of concept examplesdemonstrating natural convection and examining the parameters of the new equation of state. Thesedevelopments facilitate future work towards modelling more complex physical phenomena such asheat driven convective flow.

This paper presents a Thermomagnetic Motor, whose design of the motor is based on a thermal-magnetic coupled dynamic model, which models its magnetic as well thermal properties (magnetic permeability and thermal conductivity). The thermal processes are supposed to be influenced by the thermal conductivity, the convection and the advection. An analytical expression of the generated torque, which links this quantity to the magnetic, thermal and geometrical parameters of the generated torque is given. A design of a machine, based on this theory is proposed and the related performances are numerically simulated. An experimental verification of the performances is reported.

This paper presents the performance analysis of a linear synchronous motor which employs high-temperature superconducting (HTS) bulk magnets on the mover and normal copper windings on the stator. The linear motor is designed to drive a prototype HTS maglev vehicle in which the mover is suspended by the levitation force between HTS bulks on the mover and permanent magnets on the ground. Finite element magnetic field analysis is conducted to calculate the major parameters of the linear motor and an equation is derived to calculate the electromagnetic thrust force. Theoretical calculations are verified by the measured results on the prototype.

Transmission line flashing will cause large area and long time of blackouts,it happens in the working voltage,and it poses serious threat to the electric power system. With the development of industry,the increase of power grid capacity and rated voltage level,there are more and more flashing accidents occurred in the power system of power transmission and transformation equipment external insulation,also the damage that they bring about to our economy is getting larger.Aiming at a series of problems caused by transmission line flashing,this paper comes up with an assessment method of transmission line flashing,it improves the forecast accuracy and efficiency so as to ensure the safety operation of transmission.

Distributed optical fiber sensor can acquire the information of physical field along time and spatial continuous distribution. It plays an important role in long-distance oil and electricity transmission and security. In this paper, the author introduced the universal steps in triggering pattern recognition, which includes signal characteristics extracting by accurate endpoint detecting, templates establishing by training, and pattern matching. By training the samples acquired in the laboratory, three templates are established. And pattern matching had been done between templates and all the samples. The results show that, 87.5 percent of the samples are matched correctly with the triggering patterns they are belonging to.