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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.

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.

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.

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.

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 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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

This paper reports about the design and modeling process of high performance servo-actuated mechanisms for automatic machines. Besides being a delicate and time consuming process, coupled simulations based on virtual prototyping finally offer the chance to integrate engineering methods proper of control system engineering and mechanical design. In particular, the main target of this work is to investigate how different virtual prototyping approaches, each having increasing level of detail, can contribute to the appropriate prediction of the expected machine performance. These results are then compared with experimental data obtained on a real servomechanism prototype. The comparison quantitatively demonstrate the improvement on torque prediction and position error reduction when detailed models of the controller and the electric motor dynamics are coupled with the mechanical system model.

The poor electric conductivity of polycrystalline diamond (PCD) makes it difficult to machine with the conventional EDM process. Inappropriate selection of parameters of the power generator and the servo system leads to unstable working condition and low material removal rate. This paper introduces a method to find optimal parameters in the Electrical Discharge Grinding (EDG) of PCD materials with Taguchi method. The theory and detailed procedures are presented, experimental results are analyzed. The optimized configuration was validated through confirmation tests.

This paper presents a numerical investigation on the effect of thermal anisotropy of the top layer alloy on heat transfer and lubricant depletion on the disk surface in a heat-assisted magnetic recording (HAMR) system. The disk consists of multilayer structures and a thin layer of lubricant on the top surface. Cases under different laser powers and initial lubricant film thicknesses are examined. The top-layer alloy thermal anisotropy does show non-negligible effect on the heat transfer and lubricant depletion. With the top-layer alloy being more anisotropic, higher temperature increase and lager lubricant depletion can be observed on the disk surface. The results also show that the thermal anisotropy effect is more significant under a lower laser power but nearly keeps no much difference under different initial lubricant film thicknesses. Thus it is of importance to include the thermal anisotropy effect of the top-layer Co-alloy when simulating the heat transfer and lubricant depletion in practical multilayer HMAR systems, especially for the cases under the condition of lower laser power, as the effect cannot be neglected under such conditions.

The content of this work is the presentation of the prototype of a new active suspension system with an active air spring. As being part of the Collaborative Research Unit SFB805 “Control of Uncertainties in Load-Carrying Structures in Mechanical Engineering”, founded by the Deutsche Forschungsgemeinschaft DFG, the presented active air suspension strut is the first result of the attempt to implement the following requirements to an active suspension system: Harshness and wear: Reduced coulomb friction, i.e. no dynamic seal. Plug and drive solution: Connected to the electrical power infrastructure of the vehicle. Vehicle and customer application by software and not by hardware adaption. These requirements were defined at the very beginning of the project to address uncertainties in the life cycle of the product and the market needs. The basic concept of the active air spring is the dynamic alteration of the so-called effective area. This effective area is the load carrying area A of a roller bellow and defined by A:=F/(p-pa). F denotes the resulting force of the strut, p the absolute gas pressure and pa the ambient pressure. The alteration of this effective area is realized by a mechanical power transmission, from a rotational movement to four radial translated piston segments. Due to the radial movement of the piston segments, the effective area A increases and so does finally the axial compression force F. The prototype presented in this paper serves as a demonstrator to proof the concept of the shiftable piston segments. This prototype is designed to gather information about the static and dynamic behavior of the roller bellows. Measurements show the feasibility of the concept and the interrelationship between the piston diameter and the resulting spring force.

This paper presents the experimental results obtained of flexurally loaded wind turbine blade cross section material. All material was extracted from a wind turbine blade box girder and testing was conducted in four point configuration. The aim was to gain an understanding of the structural integrity of this lightweight material as it deforms in flexure. To allow for thorough analysis, digital image correlation (DIC) was used to produce full field strain maps of the deforming specimens. Results highlight the capability of the DIC technique to identify regions of failure, as well as the aspects responsible for them. Overall, the results present a foundation for tests on larger substructure, and eventually integration into manufacturing and maintenance aspects of the industry.

Speedy IP Traceback method (SIPT) is deficient in monitoring and position attack sources, this paper puts forward an improvement scheme based on SIPT, it only marks two-three times for the packet on the key locations, and the propose also overload rarely used fields on IP packet header to store the checkpoint information, which can traceback the attack source use these marking information, which would help to attack path-reconstruction with a low false-positive rate as a guid.