Journal of Engineering and Technological Sciences
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A Collaborative System to Manage Information Sources Improving Transport Infrastructure Data Knowledge
Get PDFThe present paper describes the WIKI RoadSMap project implemented within a start-up research program. The main objective of the project is to create a system that applies innovative technologies to information gathered to enable the acquisition of greater local knowledge and analysis of issues related to road infrastructure and directly and indirectly connected elements. By applying semantic analysis technology for the extraction, collection, integration and publication of data, WIKI RoadSMap allows users to acquire greater knowledge in order to optimize choices related to road infrastructure. The system allows more detailed and targeted dissemination of data related to the design, management and maintenance of an infrastructure. The source and type of data needed are different and heterogeneous, including information 'posted' by people with private and/or commercial purposes, or available at road agencies and/or public administrations or related to specific surveys carried out. The system platform should be available on the Web and on smartphones, both providing different levels of access and subscriptions. The spread and use of WIKI RoadSMap could have a positive impact on the market with regard to the supply of materials and specialized technical skills and companies operating in the areas of interest
Performance Analysis of Energy Storage in Smart Microgrid Based on Historical Data of Individual Battery Temperature and Voltage Changes
Get PDFIn this work, a historical data based battery management system (BMS) was successfully developed and implemented using an embedded system for condition monitoring of a battery energy storage system in a smart microgrid. The performance was assessed for 28 days of operating time with a one-minute sampling time. The historical data showed that the maximum temperature increment and the maximum temperature difference between the batteries were 4.5 °C and 2.8 °C. One of the batteries had a high voltage rate of change, i.e. above 3.0 V/min, and its temperature rate of change was very sensitive, even at low voltage rate of changes. This phenomenon tends to indicate problems that may deplete the battery energy storage system's total capacity. The primary findings of this study are that the voltage and temperature rates of change of individual batteries in real operating conditions can be used to diagnose and foresee imminent failure, and in the event of a failure occurring the root cause of the problem can be found by using the historical data based BMS. To ensure further safety and reliability of acceptable practical operating conditions, rate of change limits are proposed based on battery characteristics for temperatures below 0.5 °C/min and voltages below 3.0 V/min
Borehole Microseismic Imaging of Hydraulic Fracturing: A Pilot Study on a Coal Bed Methane Reservoir in Indonesia
Get PDFOver the last decade, microseismic monitoring has emerged as a considerable and capable technology for imaging stimulated hydraulic fractures in the development of unconventional hydrocarbon resources. In this study, pilot hydraulic-fracturing treatments were operated at a coal-bed methane (CBM) field in Indonesia to stimulate the flow and increase the reservoir's permeability while the monitoring system was set in a single near-vertical borehole. Locating event sources accurately is fundamental to investigating the induced fractures, but the geometry of a single downhole array is a challenging data processing task, especially to remove ambiguity of the source locations. The locating procedure was reviewed in 3 main steps: (i) accurate picking of P- and S-wave phases; (ii) inclusion of P-wave particle motion to estimate the back azimuth; (iii) guided inversion for hypocenter determination. Furthermore, the seismic-source moment magnitudes were calculated by employing Brune's model. Reliable solutions of locations were obtained as shown statistically by uncertainty ellipsoids and a small misfit. Based on our results, both induced and triggered seismicity could be observed during the treatments and therefore conducting intensive monitoring is important. The triggered seismicity is an undesired activity so disaster precautions need to be taken, in particular for preventing reactivation of pre-existing faults
Comparative Study of Bacterial Cellulose Film Dried Using Microwave and Air Convection Heating
Get PDFAn investigation was conducted to analyze and compare the properties of bacterial cellulose (BC) films dried using microwave and air convection heating. Prior to the drying process, 90% of the water content inside the BC pellicles was removed through vacuum filtration. After that, the required drying time was only 3-5 min using microwave heating, 95% shorter than that observed for air convection heating. The properties of the BC sheets were characterized by Fourier transform infrared (FTIR), X-ray diffractometer (XRD), color difference meter, and tensile tester machine. The results showed that the structure of the BC films was the same for the BC films dried by microwave and air convection heating, i.e. cellulose I, as observed from FTIR spectra and XRD diagrams. Moreover, their color (L*, a*, and b* values) and mechanical properties were also almost identical. However, a slightly lower crystallinity and a higher swelling degree were observed for the BC film dried using microwave heating. These results suggest that microwave heating could be an alternative method of drying BC pellicles in order to shorten the processing time and reduce energy consumption when compared to air convection heating
Impurity Removal of Waste Cooking Oil Using Hydrophobic Polypropylene Hollow Fiber Membrane
Get PDFRemoval of impurities from cooking oil is an important step in providing the possibility of WCO reuse to extend the life cycle of cooking oil, leading to a reduction of WCO disposal. This study was conducted to investigate the performance of a polypropylene (PP) hollow fiber ultrafiltration (UF) membrane for removal of impurities from WCO. The results showed that the membrane could remove water content up to 95% (at 0.1 MPa and 30 °C), but the color improvement was only 9.5% as indicated by the absorbance reduction. Within the range of the operation conditions (i.e. a trans-membrane pressure of 0.1-0.2 MPa and a temperature of 30-50 °C), the oil flux varied from 0.3 L.m"‘2.h"‘1 to 1.3 L.m-2.h-1. In long-term operation, the membrane wettability was improved as shown by the oil contact angle decreasing from 28.2 ± 1.5° to 14.4 ± 0.5°. This resulted in a higher oil flux. At the same time, the hydrophobicity was also increased, as indicated by an increase in the water contact angle from 95.4 ± 0.7° to 97.3 ± 1.1°
Scaling Up of the Pyrolysis Process to Produce Silica from Rice Husk
Get PDFRice husk is a potential alternative source of silica and silicon. The mechanism of heating (pyrolysis) for the decomposition of rice husk is an important factor in obtaining silica of high purity. Medium-scale pyrolysis to produce silica from rice husk serves as a bridge to connect laboratory-scale production to industrial-scale production. The purpose of this study was to model and scale up the pyrolysis process as a guidance for industrial-scale production. The research method used was experimentally based. An experimental investigation was undertaken in five stages. 1) Analyzing rice husk mass conversion using thermogravimetry analysis (TGA); 2) pyrolysis modeling based on a laboratory investigation using COMSOL Multiphysics version 5.3; 3) medium-scale experiments according to the modeling results; 4) validation of the modeling results by carrying out a medium-scale experiment; 5) silica purity analysis using SEM-EDX. The medium-scale pyrolysis simulation of silica manufacture from rice husk obtained a heating rate of 1.5 °C/min. There was an increase in the heating rate of 1 °C/min when compared to the laboratory-scale process. The pyrolysis of rice husk for the production of silica affects the mass conversion and selectivity of the resulting silica product. The mass conversion produced was 13.33% to 17.87% and the purity of silica produced was 63.99% to 82.74%
Structural Topology Optimization of Brake Disc Using the Equivalent Moving Load Method
Get PDFDuring the braking process, the brake disc is subjected to the moving load. The process-point of the moving load moves along a certain trajectory, which makes it difficult to design the brake disc structure by using a traditional topology optimization method. The novel Equivalent Moving Load (EML) method proposed in this paper aims to solve this problem. According to the principle of continuous photographing technology, a mathematical model was established by using the round inward polygonal approximation algorithm. The EML method equalizes the continuous dynamic load action to many finite working conditions by geometric approximation. These working conditions are placed along the trajectory. The structure of the brake disc is then optimized by the EML method. Additionally, the influence of the layout style of the brake pads and the total number of working conditions on the optimization result are discussed in this paper. The optimization results showed that the new structure is a three-annulus structure. The weight of the new structure is reduced by 57.95% compared to the initial structure by structural topology optimization using the EML method. It was proved that structural topology optimization using the EML method is efficient in optimizing a structure subjected to dynamic load
Shelf-life Evaluation of Packaged Fermented Cassava Flour
Get PDFCassava is a carbohydrate source with high productivity per hectare of plantation. Cassava is made into flour to extend its shelf life. However, traditional flour still has low quality due to its yellowish color and distinct odor. Fermented cassava flour (FERCAF) is produced by fermentation of cassava chips in a circulated retting fermenter by using a combination of Lactobacillus plantarum, Bacillus subtilis, and Aspergillus oryzae, followed by drying and milling. This process has been used successfully to produce flour with a white color and a neutral aroma. To enable industrial scale production and market introduction, the quality deterioration and shelf life of packaged FERCAF should be determined. The objective of this research was to investigate the effect of storage time and packaging type on the physicochemical properties and to determine shelf life of packaged FERCAF. FERCAF was stored in a controlled-incubator over 94 days using two packaging types: LDPE plastic and kraft paper. Based on the result, the number of microorganisms over 94 days of storage was within safe limits. The average estimated shelf life of packaged FERCAF was in the range of 3-4 months at ambient temperature. The shelf life of FERCAF packaged in LDPE plastic was approximately 15 days longer than that packaged in kraft paper
Alternative Designs for Semarang-Demak Coastal Dike and Toll Road
Get PDFSemarang city has been experiencing coastal flooding as a major problem. The flooding is inevitable due to the declining groundwater level as an impact of population growth and groundwater exploitation. The Indonesian Ministry of Public Works and Housing is currently planning to build the Semarang-Demak section of the Northern Java Coastal Tollway not only to fulfill traffic demand but also to fight coastal flooding. The purpose of this paper is to present alternative designs to support the plan and to provide recommendations based on design analyses as well as concerns from past design experiences. To the degree that is allowed by the available secondary data, reasonably detailed engineering calculations were performed to be able to present the dimensions of each alternative structure. The results of the structural and geotechnical analyses were obtained using suitable software for each type of analysis and the concerns based on past design experiences were investigated to find the most effective and efficient alternative
Brake Strategy Analysis for Industrial Normal-closed Brake Based on Rotational Inertia Test and Simulation
Get PDFIndustrial brakes pose the dilemma of weighing brake capability against brake impact since the brake torque cannot be adjusted. On the one hand, the brake torque may be insufficient to stop the movement within a limited distance or parking position. On the other hand, the brake torque may be so high it can damage the transmission chain. In this study, the traditional brake strategy and the field oriented control (FOC) brake strategy were compared through simulation and a rotational inertia test. The influence of the rated brake torque and the open-closed ratio were obtained. Based on the test and simulation results, a semi-empirical formula that defines the relationship between relative brake capability and open-closed ratio was developed. Additional simulations were performed to analyze the performance of the brake in a flexible transmission chain. As an industrial application example, the benefits and the cost of a 'smart brake' based on the FOC brake strategy were analyzed. The results indicate that the equivalent brake torque with the FOC brake strategy is a function of the real-time controllable input and open-closed ratio, which can be conducted during the braking procedure. This can be an efficient way to solve the above problems