A computational intelligence approach to solve the inverse problem of electrical DC resistivity sounding

Electrical methods have been widely used in geophysical surveying to obtain high-resolution information about subsurface conditions, since the last few decades. Resistivity is an important parameter in judging the ground properties, especially detecting buried objects of anomalous conductivity. Electrical DC (i.e. Direct Current) resistivity sounding is the commonly used technique to obtain the apparent 2-D resistivity of the region under investigation. Acquiring the true resistivity from collected data remains a complex task due to nonlinearity particularly due to contrasts distributed in the region. In this work, a radial basis function neural network (RBFNN) metamodelling approach is proposed to solve the 2-D resistivity inverse problem. The model was trained with synthetic data samples obtained for a homogeneous medium of 100O.m. The neural network was then tested on another set of synthetic data. The results show the ability of the proposed approach to estimate the true resistivity from the 2-D apparent resistivity sounding data with high correlation. The proposed technique, when executed, appears to be computationally-efficient, as it requires less processing time and produces less error than conventional metho

DEBIT AIR DAN SEDIMEN MELAYANG SUNGAI KODINA DI DESA WAYURA KECAMATAN PAMONA TENGGARA KABUPATEN POSO

The Kodina watershed with its river which empties into Lake Poso is one of the critical watersheds in the Poso watershed area. In addition to generating benefits that can be enjoyed by the community, changes in land use in the upstream watershed cannot be separated from the risk of land damage due to erosion, environmental pollution and flooding. The impact that is often seen is the increase in critical land, increased soil erosion and siltation (sedimentation) in the watershed area, and the occurrence of flooding in the rainy season and drought in the dry season. The purpose of this study was to determine the water discharge and the amount of floating sediment that was transported along the Kodina river. The purpose of this research is to provide information about water discharge and the amount of floating sediment production produced by the Kodina river which as a whole can help watershed managers in overcoming problems related to the hydrological aspects of the watershed area. This research was conducted for two months, from December 2015 to February 2016 at the Kodina Watershed, Poso Regency, Pamona Tenggara District. The method used in this research is a survey method, namely by taking direct measurements in the field, which includes: measuring water flow and taking water samples for analysis of floating sediment content. The results of the calculation of the data collected during the research period after being processed show that the water discharge flowing in the Kodina river cross section is 17.10 m3 / s and the amount of floating sediment transported with river water runoff is 36.53 gr / ltr. The relationship between water discharge and floating sediment discharge has a positive relationship with a correlation value of 0.895. This shows that the increase in the Kodina River Water Flow will be followed by an increase in floating sediment loads.Keywords: Water Discharge, Floating Sediment, Watershed

HUBUNGAN DEBIT AIR DAN TINGGI MUKA AIR DI SUNGAI LAMBAGU KECAMATAN TAWAELI KOTA PALU

The measurement of waterflow debit is very needed to know the potency of water resource at a  river flow area. Debit is the  water volumethat flows in one time. The consentration time is a needed time for rainfall running off for the farest spot to the control observed spot. The measurement of waterflow speed can be used as a tool to monitor and evaluate water balance at one area by approaching the potency of existing surface water resource. The aimed of the research is to find out the correlation of water debit and water surface height at Lambagu River Tawaeli District Palu City. The research was conducted on February to April 2015 at River Lambagu Tawaeli District Palu City. Furthermore, the data gathered involved primary data; data gathered in the location directly, they were the data of the width of river wet profile, the length of river wet profile, the depth of river wet profile, the speed of riverflow, the height of  surface water, abd rainfall while  the secondary data was the data that gathered from library, literature, available reports of office and involved institution, as a supporting data that involved: topography condition, geomorphologi, land covering, rainfall around Lambagu Riverflow Area for last 4 years that gathered from Palu-Poso BPDAS and climate condition at Lambagu River of Tawaeli District Palu City. After research procedures were done, the data gathered analyzed by  using  logaritme method.The result of the research showed that the water debit at Lambagu river Pantoloan subdistrict during the reserach period had the average rate of  0.757 m³/second and the height of water surface at Lambagu river was about0.26 m. The correlation between water debit and water surface height showed a strong (positive) correlation in formula of Q = 0.157h0.654x  with the rate of correlation (R2)=0.905.Keywords :Water Debit, Height of water Surface, Riverflow Area

EROSI PADA BEBERAPA PENGGUNAAN LAHAN DI SUB DAS OLONJONGE KABUPATEN PARIGI MOUTONG SULAWESI TENGAH

The land has great potential in supporting human life activities. Human dependence on land resources which continues to increase as the number of population that causing the increase of population pressure to land resources so that land use is very difficult to avoid, as well as happening of land use in Das Olonjonge of Parigi Moutong District of Central Sulawesi. This study aims to find out a scale of erosion and surface runoff of some land using in the regions of DAS Olonjonge. This study was conducted in June 2015 until November 2015. This study was conducted in DAS Olonjonge sub-district in the area of the research 3.391,43 Ha. Administratively, the research area is located in South Parigi Sub-District, Parigi Moutong District, Central Sulawesi. This research used methods of measuring and collecting data, by placing the plot of 20 m x 4 m size that was put in some lands use. The result of this study was analyzed in Laboratory at Forestry Faculty of Tadulako University. Of the three land cover conditions, the largest soil erosion can be found on mountainous terrain types (plot 1) with the weight of the soil mass eroded is 2.388,79 gram or 796,26 kg/ha and the smallest on  the use of peanut lands type (plot 2) is 818,48 gram or 272,83 kg/ha. The largest surface of volume runoff is found on terrain land with an average value 33,64 liter or 11,21 m3/ha and the smallest on the peanut land which has the average value of runoff volume is 19,23 liter or 5,41 m3/ha.Keywords: Erosion, Surface Runoff, DAS

Two-dimensional DC resistivity mapping for subsurface investigation using soft computing approaches

In geophysical subsurface surveys, difficulty to interpret measurement of data obtain from the equipment are risen. Data provided by the equipment did not indicate subsurface condition specifically and deviates from the expected standard due to numerous features. Generally, the data that obtained from the laws of physics computation is known as forward problem. And the process of obtaining the data from sets of measurements and reconstruct the model is known as inverse problem. Researchers have proposed multiple estimation techniques to cater the inverse problem and provide estimation that close to actual model. In this work, we investigate the feasibility of using artificial neural network (ANN) in solving two- dimensional (2-D) direct current (DC) resistivity mapping for subsurface investigation, in which the algorithms are based on the radial basis function (RBF) model and the multi-layer perceptron (MLP) model. Conventional approach of least square (LS) method is used as a benchmark and comparative study with the proposed algorithms. In order to train the proposed algorithms, several synthetic data are generated using RES2DMOD software based on hybrid Wenner-Schlumberger configurations. Results are compared between the proposed algorithms and least square method in term of its effectiveness and error variations to the actual values. It is discovered that the proposed algorithms have offered better performance in term minimum error difference to the actual model, as compared to least square method. Simulation results demonstrate that proposed algorithms can solve the inverse problem and it can be illustrated by means of the 2-D graphical mapping

STUDY OF USE FERMENTED BANANA Musa paradisiaca (Linnaeus, 1761) HUMPS AS ORGANIC FERTILIZER TO IMPROVE NATURAL FEED AVAILABILITY IN NURSERY OF HOVEN’S CARP Leptobarbus hoevenii (Bleeker, 1851) FRY

Plankton as a natural feed is thought to be a factor that affects the growth of hoven’s carp fry. Plankton abundance can be increased by the addition of organic fertilizers containing nutrients (nitrate and phosphate). Nutrients abundance can be increased by addition of fermented banana hump’s This research aimed to determine the use of fermented banana’s hump to increase the availability of natural feed nursery and the growth of hoven’s carp fry. The method of this research used a completely randomized design with four treatments and three replications, i.e: P1 (control), P2 (5,0 ppm), P3 (7,5 ppm), and P4 (10,0 ppm) addition of fermented banana’s hump. The measured parameters were nitrate, phosphate, plankton abundance, growth and water quality. The results showed the dose of addition of banana weed fertilizer had an effect (P< 0.05) on the abundance of natural feed and the growth of hoven’s carp fry. Results of water quality measurement showed the parameters of temperature ranged from 25 to 27 °C, pH ranged from 6,23 to 7,53, DO ranged from 3,40 to 11,36 and ammonia from 0 to 0,001 mg/l. The recomended dosage of fermented banana’s hump was 10 ppm for 1 l of water media

A review of thermoelectric energy harvester and its power management approach in electronic applications

Thermoelectric energy (or power) harvester is a kind of renewable energy approach that extracts waste heat from targeted device or object to generate electrical power. It is an advance technology widespread among researchers for decades. By having plenty of promising advantages, the thermo-electric power harvester is being developed in types of feasible interfaces. This review paper focused on research had been done relating to thermo-electric power harvester, in the macro scale and mainly in the micro scale of power harvester. Several designs of thermo-electric technologies will be further discussed in this paper. This paper reveals the viability of thermo-electric power harvester in sustaining electric supply for micro-electronics applications. Eventually, some add-on is being proposed at the last part of the paper

The applications of ultrasonic sensor

Ultrasonic sensor usually used for distance measurement and obstacles detection. This sensor is low cost and suitable for range up to few metres for distance measurement applications. However, this sensor has limitations which are wide beam width and sensitivity to the mirror – like surfaces. Despite the disadvantages, there are several applications of these sensors such as wireless obstacle detection, collision control and avoidance, distance measurement and smart parking system. Each of the applications has difference approaches suggested by the researchers. Baharuddin M et al. proposed that in order to give a reliable distance measurement, both infrared and ultrasonic sensors are used together [1]. This paper discussed about four applications of ultrasonic sensors in details which are wireless obstacle detection, collision control and avoidance, distance measurement and smart parking system

Detection of low metal landmines using EMI

Electromagnetic induction (EMI) sensors have been used extensively to locate buried landmines by detecting the metal present in such mines. Near field, EMI sensing from 10’s Hz up to 100’s of kHz has been successful in detecting metallic target. However, landmines vary in their construction from metal-cased varieties with a large mass of metal to plastic-cased varieties with minute amounts of metal. Unfortunately, there is often a significant amount of metallic debris (clutter) present in the environment. Consequently, EMI sensors that utilize traditional detection algorithms based solely on the metal content suffer from high false alarm rates. EMI sensors usually consist of a pair of coils, one of which is used to transmit either a broadband pulse or a continuous wideband electromagnetic waveform. The transmitted field induces a secondary current in the earth as well as in any buried conducting objects. In the case of pulsed excitation, the transmit waveform is quenched quickly and the receiving coil measures the decaying secondary field that has been induced in the earth and subsurface objects. In the case of wideband excitation, the receiving coil is placed within the magnetic cavity so that it senses only the weak secondary field radiated by the earth and buried objects. The phenomenology associated with EMI has been studied extensively. A simple phenomenological model that describes the measured time-domain waveform as a weighted sum of decaying exponentials has been shown to provide an accurate model for such sensors. In general, the decay rates associated with metallic objects are slower than that of the earth, so there is more energy in the received signal when a metallic object is present under the surface of the earth. This simple phenomenology allows very basic signal processing to be employed, for example either an energy detector or the overall amplitude of the signal in a given time gate, may be used when the goal is to detect any metallic subsurface object. However, in highly cluttered sites, such processing can be the source of many alarms