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Single Phase Inverter Circuit Based on Frequency Variation For Controlling The Speed of a Capacitor Motor
Full text linkThis research is aimed to build a single phase inverter circuit as a speed controller for a single phase induction motor which operates based on the variation of frequency. In this circuit, the variation of frequency is developed by an oscilator which work by the variation of the value ratio between a capacitor and a resistance. The capacity of the capacitor is choosen constant while the value of the resistence is varied by a potentiometer. The performance of this circuit is then examined to drive a single phase induction motor capacitor start and run tipe in no load and loaded conditions. The result showed that this inverter circuit can control the speeds of the capacitor motor proportionally to the stator voltage frequencies. The others motor quantities such as motor voltage, current, power, and slip also observed in this study. The result showed that the other motor quantities namely motor voltage, current, power also increased as the motor frequency is increased. Keywords: single-phase, inverter-circuit, frequency, oscilator, capacitor-motor
Analysis of shear wave velocity to a depth of 30 m (Vs30) inTalise Village using Refraction Mikrotremor method
Full text linkTalise is an area with a fairly high construction activities at the present time. The condition of the buildings in this area is susceptible to damage. This problem is mainly caused by constructing many buildings without considering the structure of subsurface. The purpose of this study is to determine the classification and types of rock below the surface through the analysis of shear wave velocity to a depth of 30 m (Vs30) instudy area. The method used in this research wasRefraction Mikrotremor (Remi) that records a shear wave propagationhappening below the surface. Data processing was performed using Surface Wave Analysis Wizard and WaveEq (Surface Wave Analysis) programs.The interpretation of 6 tracks shows that the greater depth obtained, the greater value range of shear wave velocity happened. The results of this study werethe form of classification and subsurface rock types with 4 different study sites, namelyAbadi field, Jabal Nur field, Mapolda Sulteng, and School of Model Terpadu Madani. The former study site is classified astype E (soft soil), while the others are classified as type D (stiff soil). Â Keywords:Refraction mikrotremor (ReMi), shear wave velocity, Vs30, classification of rock
Image based fire alarm system
Full text linkIn general, any house or other building has the potential to experience fire. It requires fire detection devices as tools for early and effective fire prevention. The purpose of this research is to design and create an image based fire alarm system by using computer (PC) and a webcam as the main equipment to detect the presence of fire based on RGB colour values of fire from the recorded image. The recorded image by webcam will be processed on a computer (PC) via java program has been created in which the algorithm to detect the presence of fire by fire RGB colour value. From the test results obtained the RGB colour value of fire that can be detected by image-based fire alarm system for red (R), green (G), and blue (B) were 229-246, 188-212, and 100 -110, respectively. The program also set to emit a sound when a fire is detected. Â Keyword :Fire Detection system, fire image, fire detection progra
Mapping of Tsunami Disaster Risk Based Spatial in Palu
Full text linkMapping tsunami risk level has been carried out in the city of Palu in order to determine the areas at a tsunami risk with a certain level. Tsunami risk is mapped by incorporating components of the tsunami threat, the physical, social vulnerability, economic vulnerability, environmental vulnerability then weighted using the Analytical Hierarchy Process (AHP) and subsequently processed using GIS software (Geographic Information System) in order to obtain spatial-based data. The percentage of tsunami risk areas is 1.4% (5 km2) of 366.89 km2 the total area of ​​Palu which distributed into six districts: District of Tawaeli of 25.47% (1.28 km2), District of Mantikulore 22.32% (1.12 km2), District of West Palu 18.95% (0.95 km2), District of North Palu 14.51% (0.73 km2), District of East Palu 12.22% (0.61 km2), and the District of Ulujadi 6.53% (0.33 km2). All those districts which potentially at risk tsunami are the districts directly adjacent to the Gulf of Palu. While the other two sub-districts: the District of Tatanga and District of South Palu located far from the beach so do not have exposure to the tsunami.
Keywords:Tsunami, risk, vulnerability,spatial, AH
Mapping Projections Of Water Hardness Of The Groundwater In Palu Using The Web-Based Google MapsAPI
Full text linkThe groundwater research has conducted for mapping the distribution of water hardness using the web-based Google Maps API application and for determining the level of the average hardness of the ground water in the City of Palu, which has higher water hardness. All sampling points which were labelled green, yellow and red, where green and yellow colour which indicated that the hardness value was still low, but red indicatedan high hardness values. The obtained hardness results in 4 districts in Palu by using the titration method of complexometry or EDTA titration were different, namely the District of South Palu, West Palu, East Palu, and District of North Paluwere12,54 mg/l – 15,68 mg/l, 11,87 mg/l – 98,58 mg/l, 10,53 mg/l – 15,68 mg/l, and t 10,3 mg/l – 89,59 mg/l, respectively. However, these resultswere still under the maximum threshold. It was influenced by the content of water-soluble salts of hardness ions such as Ca2+, Mg2+, and Fe2+, and it was also affected by CO2free and a large amount ofNaCl, which can increase the water hardness. Keyword:Water hardness, groundwater, Google Maps API, ComplexometryTitratio
Study of the zones of gold mineralization in Siliwanga village, Lore Peore district, Poso regency, using geomagnetic method
Full text linkoai:ojs.pkp.sfu.ca:article/4429Talise is an area with a fairly high construction activities at the present time. The condition of the buildings in this area is susceptible to damage. This problem is mainly caused by constructing many buildings without considering the structure of subsurface. The purpose of this study is to determine the classification and types of rock below the surface through the analysis of shear wave velocity to a depth of 30 m (Vs30) instudy area. The method used in this research wasRefraction Mikrotremor (Remi) that records a shear wave propagationhappening below the surface. Data processing was performed using Surface Wave Analysis Wizard and WaveEq (Surface Wave Analysis) programs.The interpretation of 6 tracks shows that the greater depth obtained, the greater value range of shear wave velocity happened. The results of this study werethe form of classification and subsurface rock types with 4 different study sites, namelyAbadi field, Jabal Nur field, Mapolda Sulteng, and School of Model Terpadu Madani. The former study site is classified astype E (soft soil), while the others are classified as type D (stiff soil). Â Keywords:Refraction mikrotremor (ReMi), shear wave velocity, Vs30, classification of rock
Identification the distribution of iron ore used resistivity geoelectric method in the Ogowele Village, Tolitoli Regency.
No full textIt has been used resistivity geoelectric method with Wenner-Schlumberger configuration. The aim is to identify the distribution of iron ore located in the Ogowelevillage, Tolitoli regency. Research has been done using geoelectric method Wenner-Schlumberger configuration as well as data processing and data modeling using software EarthImager 2D in the 2D cross-sectional shape. Based on 2D modeling results resistivity value of the iron ore ranging from 55.8 to 156.2 Ωm. The existence of iron ore largelyspreadin South, West and East sites.Keyword: geoelectric, resistivity, EarthImager 2D, iron or
Estimation of the elasticity characteristics of the subsurface rocks using shear wave
Full text linkThe research using the method of refraction microtremor (REMI) has been carried out in the village of Salua, District of Kulawi. Seismic method of refraction microtremor (REMI) is an effective and efficient method for determining the shear wave velocity (shear wave) each bedding soil. The purpose of this study was to determine the subsurface structure based on the propagation speed of shear waves and to estimate the elasticity characteristics of the subsurface rocks. Data processing is divided into two phases. The first stage is done by using two programs that use the Surface Wave Analysis Wizard program and WaveEq (Surface Wave Analysis) program. The second stage determines the shear modulus of rock. From the data processing of the 6 lines can be seen that the subsurface structure is dominated by dry sand with shear wave velocity range of 80 m/s with a shear modulus range of 10,24-70,56 N/m2 and by soil with shear wave velocity in the range of 120 m/s with a shear modulus from 38,16-108 N/m2, and also by clay with shear wave velocity in the range of 405 m/s with a shear modulus 377,25 N/m2. Keywords: Microtremor refraction (ReMi), shear wave velocity, shear modulu
spatial analysis on the location of potential danger of flooding in Regency of Donggala using Analytical Hierarchy Process (AHP)
Full text linkThe research on the location of potential danger of flooding using spatial analysis was conducted in Regency of Donggala, Central Sulawesi Province. The purposes of this study are to determine the causes of flooding by using Analytical Hierarchy Process (AHP) and to map the flood potential of hazard areas using spatial analysis. This study used six factors causing flooding, namely watershed characteristics, slope, soil type, land cover and use, flow accumulation, and the level of precipitation. In this study, the Regency of Donggala divided into two main area: the north and south based on differences in physical conditions of each region. Based on the weighing results using the AHP for northern part of Donggala, the percetage of factors causing flooding were characteristic of the watershed by weight of 45.28%, land use 23.91%, flow accumulation 14.88%, slope 8.44%, rate of rainfall 4.75% and soil type 2.74%. On the other hand, the factors causing flooding in southern part of Donggala were land use reached 46.09%, watershed characteristics 23.59%, flow accumulation 12.65%, slope 8.91%, precipitation levels 5.21%, and types of soil 3.54%. These factors then overlaid and used to calculate the value of danger. Based on the spatial analysis, the potential locations of flooding in Donggala were classified into potentially vulnerable in the area of 44321.39 hectares, potentially mid-vulnerable being 144099.75 hectares and areas that are not potentially flood being 281709.49 hectares. The flood in Donggala is mostly influenced by a broad watershed characteristics and the use of public land which cause the increase of accumulation flow in the rainy season. Â Keywords:spatial analysis, AHP, flood hazards
Study of Metal Mineralization Zone Using Induced Polarization (IP) Method in Bale Village Tanantovea District Donggala
Full text linkABSTRACT
Research to determine the distribution of metal mineralization zones have been conducted in the Balevillage, TanantoveaDistrict, Donggala regency using induced polarization time domain method with the dipole-dipole configuration. Measurements were made using geoelectrial supersting R8IP where measurements were conducted on 4 lines with electrode space of 4 meters. The data of induced polarization were processed using the software of Earthimager 2D. The interpretation is based chargeability and resistivity parameters supported by the regional geological information of the research area. Based on the result, can be concluded that the rocks structure beneath the surface of research area consists of fourprimary lithology units, namely sandstone, limestone, conglomerate rocks, and metamorphics rocks. Mineralization zone, which is quite rich in metals, lies in the sandstone layers with high chargeability of 50 ms - 150 ms, which is supported by the low resistivity in the range of 23 Ωm - 88 Ωm and anomalies appear West-East direction at the depth of ± 10 m - 44 m.
Keywords: Metal mineralization zone, Induced polarization, Chargeability, Resistivit