Universiti Teknikal Malaysia Melaka: UTeM Open Journal System
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Development of a Low-Latency Wireless Telemetry System for Monitoring Patients Heart Rates
No full textTelemetry systems provide a means to monitor the physical state of a machine, human beings, and environmental conditions. The need for a telemetry system arises due to the increasing desire to simultaneously monitor, measure and record critical data of patients located at different locations at optimal cost. Toward this end, a wireless telemetry system was designed and implemented, specially for small-scale medical applications, specifically, for proper monitoring of the heart-rates of mostly elderly patients. In order to enhance the capabilities of the system, an infrared-based pulse Oximeter sensor was designed and integrated into the telemetry system, and this sends the acquired data to an Arduino microcontroller for pre-processing. The controller sends the pre-processed data to a coordinator PC over a ZigBee mesh wireless network, via a graphical user interface (GUI). For seamless transfer of data from source to destination, a source routing algorithm was applied to route the desired data over the proposed ZigBee network. Thus, an optimized source routing algorithm was evolved, and applied to the telemetry system in order to lower the latency of data transmission of the nodes over the wireless network. Finally, the performance of the optimized routing algorithm was compared with the existing source routing algorithm, and the wired telemetry system. Results show that data routing through the wired telemetry has much lower latency among the investigated routing schemes, and the optimized source routing algorithm transmits data with substantial gains in throughput, and achieved average latency about half the latency of the source routing algorithm
Capacitor voltage balancing with Reduction of Arm current and THD control of MMC: A modified triangular injection approach.
No full textFor high power applications, in recent time, multilevel converter has become popular because of the composition of a number of DC sources. In both variable and controllable frequency system, stair voltage output waveform of this type of converter is controllable. Different types of DC sources like as batteries, fuel cells, solar cell, wind and micro turbines are used in Modular Multilevel Converter (MMC) topology has been popular in the distributed energy resources area. Harmonic profile of a converter with a modulation scheme much depends on the carrier frequency used in it. On the other hand, with the control of Total Harmonic Distortion (THD), the arm current control is also the necessity to drive an MMC in smooth operation. Imbalance of the SM capacitor voltage affect the arm current as well as the life time of the capacitor. In this way the overall performance of the converter could be affected. As a result, several efforts of research in this area focuses on to minimize THD, to balance the capacitor voltage of Sub-module (SM) and to control the arm current of the converter. This paper proposed a modified triangular injection modulation structure for MMC converters to maintains minimum harmonic profile as well as to achieve lower arm current and capacitor voltage balancing of SM within a single algorithm structure. Some well-known modulation methods are compared with proposed method so that percentage of THD and arm current can be identified as minimum and quality of the output voltage is better
ARTIFICIAL BEE COLONY OPTIMIZATION ALGORITHM WITH FLEXIBLE MANIPULATOR SYSTEM (FMS)
No full textThis paper presents the Artificial Bee Colony (ABC) optimization algorithm with application to flexible manipulator system (FMS). ABC optimization algorithm that proposed in the previous literature can generate thousands of solutions to find the best parameters in automatically to solve the optimization problems. In this paper, ABC algorithm is used to tune the parameters of the PID controller of FMS to obtain the best performance of hub angle in FMS with the used of different performance criteria. Several conditions are set to determine which performance criteria is most suitable to tune the PID controller to obtain the best FMS performance.
A Study On Gasoline Engine Fuel Octane Numbers Using Accelerometer Analyzing With Multi Statistical Techniques
No full textOctane numbers are considered as one of the most important things element in fuel to ensure the performance of the engine. Octane numbers are also can be the cause of failure to the engine. This study is present about the performance of the engine that relates to the octane numbers and compression ratio. The experimental procedure was performed by using three specimen fuels within the specific range of speed at the engine. Data acquisition involved the vibration signal recorded by the accelerometer sensor. The vibration signal that produced by dynamic response of combustion engine has been analyzed using Fast Fourier Transform (FFT). All the data recorded are filtered using the MATLAB to get the valid data. The data obtained from the experiment were analyzed using statistical analysis method to make the interpretation of the data obtained. Mean absolute percentage error and root mean square error has been showing the suitable fuel for the engine N43B20. Correlation process has been proved that it can be used as a standard for determining the suitable fuel for the engine through statistical analysis which is non-destructive, low cost and efficient method
Marketing in Malaysian Technology Firms
Get PDFToday’s world technology recognizes Internet and World Wide Web as two of the main communication mediums in technology firms. modern technology and social networking turn out to be a part of a large number of people’s lives. technology firms are challenged with this fast-moving social network in organization that encourage viral marketing too. There has been little study about the effect of viral marketing towards technology firms. This paper aims to explore the factors that influence the effectiveness of viral marketing, determine the most influential factor and identify the impacts of onlinecontents that influence the effectiveness of viral marketing. a quantitative method was used and 384 respondents from Southern Region Malaysia participated in the survey. The results showed that all the motivational factors like playfulness, community-driven, perceived ease of use, and perceived usefulness had significant impact on the viral marketing in the Malaysian technology firms. Two other factors like critical mass and peer pressure were found to be insignificant in this study. The findings may contribute to the judgement on Malaysian technology firms about viral marketing that blend firm skills, knowledge and technical leadership roles to manage emerging technologies, develop innovative solutions and complex firm’s problems
A High Frequency Ring-VCO with Wide Tuning Range
No full textIn this paper, a high frequency ring-VCO using an improved differential delay-cell (DD-cell) is presented. The proposed DD-cell benefits from a bandwidth extension technique. Facilitated by the wide band cell, the oscillation frequency of the proposed VCO can be increased up to 15.45 GHz. The DD-cell has tunable loads, which is used to change the operating frequency of the proposed VCO between 6-15.45 GHz. The proposed VCO has been designed and simulated in CMOS 65nm process with 1V supply voltage and consumes about 4.38 mW of power when oscillating at 15.45 GHz and 3.7 mW for 8 GHz output signal. The FoM of the proposed ring-VCO is equal to 153.7 dBc/Hz
Enhancement of Voltage Stability with Unified Power Flow Controller Considering Loadability Analysis
Get PDFVoltage stability is an important issue in planning and operation of electric power system during both normal and under contingency conditions. This paper presents line voltage stability index (LVSI) for transmission lines voltage stability assessment and evaluation. The system stability under maximum loading and contingency conditions are analyzed using optimal power flow analysis. FACTS device is considered for a real-time control and a dynamic reactive power compensation of the system. Voltage source-based power injection model of unified power flow controller (UPFC) is used for the minimization of voltage deviation and losses on the network. Optimal location and sizing of UPFC is carried out using grey wolf optimization (GWO) technique in order to identify an optimal location where the FACTS device will be installed. UPFC device has proven to increase the line transmittable power, controls the voltage magnitude at the buses as well as enhancing the stability and security of the power system. The various conditions and scenarios used to test the efficacy of this model for system stability and security under contingency conditions are demonstrated on standard IEEE 14-bus test system
The Spectral Method for the Synthesis of Integral H-sequences with an Ideal Periodic Autocorrelation Function
Get PDFIn problems of signal discrimination, orthogonal cyclic sequences with good periodic autocorrelation functions (PACF) are most widely used. There are published studies on binary cyclic sequences with low PACF side lobes that do not possess the property of orthogonality for a length of N > 4. Hence, we propose the systems of orthogonal multilevel integer cyclic sequences of N = mn length, for which the cyclic convolution coincides with the m-convolution (H-sequence), which can be very effectively calculated. It is proposed to use amplitude phase shift keying (APSK) to transmit the Hsequence over the communication channel. The purpose of this study is to develop a regular algorithm for the synthesis of Hsequences of arbitrary length N = mn based on an analysis of their spectral properties. Studying the properties of the twiddle factors of the Fourier transform matrix in the basis of the Vilenkin-Chrestenson function allowed for developing a synthesis method in the frequency domain of multilevel integer H-sequences with ideal periodic autocorrelation functions
The Influence of Current on Laser Welding on Mechanical Properties and Micro Structures of Dissimilar Metal Joints
Get PDFThe joints of dissimilar metals have several problems because they have different mechanical properties and microstructures. This problem can be solved by using laser welding because the resulting energy focus and hot zone around the welding joint is minimal. The parameters that are important in welding either using welding laser or other welding process is the current. Thus, this study examined the joint of dissimilar metals i.e low carbon steel (mild steel A36) and stainless steel (stainless steel 304) using laser welding. The result of the laser welding joint with a strong variation of current tested its mechanical properties with tensile test and seen its micro structure with photo Scanning Electron Microscopy (SEM). Tensile test results on the current variable 410 - 440 Ampere obtained fracture is on the side of mild steel A36, while at 450 Ampere current strength obtained a fault on the laser welding joints, where the point of the break is below the point of broken mild steel A36. Based on the tensile test, the suitable current strength for nonlinear steel joint of A36 mild steel with stainless steel 304 is 410 - 440 Ampere. In the result of the SEM photo, it is seen that on all variables of the current strength is obtained a photo of the porosity. Based on the microstructure, it is obtained that the results of laser welding are not perfect. This causes easy corrosion and cracks occur so that the laser weld tensile test results are initially good, after some time the results will go down
Prediction And Optimization Of En8 Mild Steel Material Removal Rate And Surface Roughness Using Response Surface Methodology
Get PDFThe demand for EN8 mild steel in the industry is high due to its integral mechanical properties. However, conventional machining of EN8 mild steel is a challenging task. In this research work, prediction and optimization of EN8 mild steel Material Removal Rate (MRR) and Surface Roughness (Ra) using Response Surface Methodology (RSM) was investigated. The dimension of the EN8 mild steel material was 120 mm diameter and 80 mm in length. The turning operation of the ENS mild steel was carried out using a M42 HSS single point cutting tool. To minimize any form of error, the machining operation was done in a dry environment. A TR 100 Surface Roughness Tester was used to carry out the surface roughness measurement of the EN8 mild steel in a transverse direction. This process was repeated three times and the average value of three measurements recorded. The data generated was analyzed using Response Surface Methodology. The results obtained revealed an R2 value of 0.9985 and 0.9978 for Material Removal Rate (MRR) and Surface Roughness (Ra) respectively. Besides, it was observed that the feed rate, spindle speed, and depth of cut, had significant influence on material removal rate. Nevertheless, unlike the other parameters evaluated, it was only feed rate that had significant influence on surface roughness. The results obtained from the numerical optimization solution revealed that optimum machining setting of spindle speed of 220 rpm, feed rate of 0.14 mm/min and a depth of cut of 1.5 mm will result in a turning process with an optimum material removal rate of 12598.5 mm3/min and surface roughness of 0.87785 µm, and with a composite desirability value of 98.9%