Applied Mechanics and Materials Vol. 785

Abstract: Batteries are essential components of most electrical devices and one of the most important parameters in batteries is storage capacity. It represents the maximum amount of energy that can be extracted from the battery under certain specified condition. This paper presents the analysis of charging and discharging battery signal using periodogram. The periodogram converts waveform data from the time domain into the frequency domain and represents the distribution of the signal power over frequency. This analysis focuses on four types of batteries which are lead-acid (LA), lithium-ion (Li-ion), nickel-cadmium (Ni-Cd) and nickel-metal-hydride (Ni-MH). This paper used battery model from MATLAB/SIMULINK software and the nominal voltage of each battery is 6 and 12V while the capacity is 10 and 20Ah, respectively. The analysis is done and the result shows that varying capacity produce different power at a frequency and voltage at DC component.

Abstract: Renewable energy is an alternative option that can be substituted for future energy demand. Many type of battery are used in commerce to propel portable power and this makes the task of selecting the right battery type is crucial. This paper presents the analysis of voltage charging and discharging for lead acid battery using time-frequency distribution (TFD) which is spectrogram. Spectogram technique is used to represent the signals in the time-frequency representation (TFR). The parameter of a signal such as instantaneous root mean square (RMS) voltage, direct current voltage (V_DC) and alternating current voltage (V_AC) are estimated from the TFR to identify the signal characteristics. This analysis, focus on lead-acid battery with nominal battery voltage of 6 and 12V and storage capacity from 5 until 50Ah. The battery is a model using MATLAB/SIMULINK and the results show that spectrogram technique is capable to identify and determine the signal characteristic of Lead Acid battery.

Abstract: Environmental concerns, dependency on imported petroleum and lower cost alternative to gasoline always motivated policymakers worldwide to introduce electric vehicles in road transport system as a solution of those problems. The key issue in this system is recharging the electric vehicle batteries before they are exhausted. Thus, the charging station should be carefully located to make sure the vehicle users can access the charging station within its driving range. This paper therefore proposes a multi-objective optimization method for optimal placement of quick charging station. It intends to minimize the integrated cost of grid energy loss and travelling of vehicle to quick charging station. Due to contrary objectives, weighted sum method is assigned to generate reference Pareto optimal front and optimized the overture by genetic algorithm. The results show that the proposed method can find the optimal solution of quick charging station placement that can benefit electric vehicle users and power grid.

Abstract: In general practice, soil investigation (SI) incorporating bore hole sampling produced the most reliable value of the relevant soil parameters for the purpose of actual calculation on factor of safety (FOS) in slopes even tough time consuming and very expensive. Assessments of slope stability using electrical parameters have least been research by many scholars due to non-destructive and very sensitive and it is attractive tool for describing the subsurface properties of the slope without disturbing the physical characteristic of the soil. The method has been applied in various contexts like groundwater exploration, agronomical management by identifying areas of excessive or soil horizon thickness and bedrock depth. This paper investigates the relationship between electrical resistivity and SPT-N values of sandy soils. The research work consists of field resistivity surveys, soil boring and soil characterization tests. Field survey included 1D vertical electrical sounding (VES) and SPT method in obtaining SPT-N value. The test being conducted on 3 different areas and 11 sandy soil sample with electrical, physical soil characterization data which being used for least-squares regression method. In this part of the study, correlations of electrical resistivity with SPT values of soil were assessed. The findings showed good correlation between the resistivity and soil properties. The obtained results demonstrate the possibility usage of electrical resistivity survey as an alternative to standard penetration test SPT is possible.

Abstract: The article is concerned with the advanced automatic control system of electrode positioning at electric arc steel making furnaces and ladle furnaces. Analysis of structure of modern electrode positioning control systems’ nonlinear controllers for electric arc furnaces and ladle furnaces is considered. Disadvantages of these systems were analyzed. A control system with a conventional structure from well-established foreign suppliers was compared with the advanced automatic control system of electrode positioning.

Abstract: Magnetometer is an instrument to measure Earth’s magnetic field magnitude. Microelectromechanical system (MEMS) magnetic sensor is implemented in the device system since it consists of multi-axis magnetic field sensing driven in a single microchip physical scale at low power consumption. The magnetometer is equipped with built-in data logger system as an automatic data storage system to overcome data loss. The Anisotropic Magnetoresistive (AMR) sensor is the best MEMS magnetometer sensors, since it consumes low power (3.3Vdc), small physical size (less than 8.1mm³) and considerable 200nT resolution for Earth’s magnetic field sensing. The magnetometer consumes 5.0Vdc for complete system operation. The instrument device is useful for scientific and geophysical field to observe and measure geomagnetic field magnitude, where the measurement could be taken anywhere around the globe. The mobile wireless magnetometer was tested and experimental measurement was performed at Faculty of Electrical Engineering, Universiti Teknologi MARA, Selangor, Malaysia (coordinate: 3.07°N, 101.50°E).

Abstract: This paper presented a reliability model for Remote Terminal Unit (RTU) based on redundancy concept. The redundancy concept discusses the serial and parallel reliability model for Remote Terminal Unit (RTU). RTU works on the success of reliability model. The reliability performance is measured by tracking the diverse sorts of failures alongside the quantity of failures that is accumulated by a RTU. The reliability model was evaluated based on reliability distributions namely Exponential, Binomial, and Poisson reliability distributions.

Abstract: The aim of this research is to develop a low power, low cost and energy efficient transceiver model which is integrated with programmable microcontroller and ZigBee transponder. A combination of programmable microcontroller with ZigBee transponder is used to control the transceiver module with computer commands. It has b een simulated for transmitting and receiving the communication signals from any movable device with more efficiently and use low power consumption. ZigBee Transponder is preferable as compared to radio frequency identification (RFID) due to IEEE 802.15.4 standard that promises stable data transmission with low power consumption device and having higher network flexibility. PIC 16F877A programmable microcontroller with coding in Mikro C software is simulated and used with computer control instructions. Series of experiments has been conducted to ensure the stability and low power consumption of this model.

Abstract: Recently, position control of URVs has been a challenge due to the buoyancy forces, and high current load of ocean. In this paper, variable ballast tank (VBT) of a spherical URV is developed as vertical motion actuator, and the problem of internal dynamic forces which caused by empty space inside the VBT has been discussed. In order to test the stability of the proposed system, the experimental model of URV has been tested in 1-5 meter underwater depth.

Abstract: To provide fast digital communications systems, energy efficient, high-performance, low power is critical for decoding mobile receiver device. This paper proposes a low power optimization techniques in the Add Compare Select (ACS) unit for Space Time trellis codes (STTC) Viterbi decoder. STTC Viterbi decoder is used as a reference case. This paper discusses about how to lower the power in the ACS architecture, to optimize the Viterbi decoder STTC in reducing the total power consumption. Based on the results of design and analysis, power consumption Viterbi decoder modeling, low power system for STTC Viterbi decoder is proposed. Design and optimization of ACS unit in STTC Viterbi decoding is done using Verilog HDL language. Power analysis tools in the software Altera Quartus 2 is used for the synthesis of total system power consumption. Optimization strategy showed an increase of 83% power reduction compared to previous studies.