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ESTIMATION OF DATA MEMORY CAPACITY FOR CIRCULARLY POLARIZED SYNTHETIC APERTURE RADAR ONBOARD UNMANNED AERIAL VEHICLE PLATFORM (CP-SAR UAV)
No full textPreviously only linear polarization is widely used in the Synthetic Aperture Radar(SAR) system onboard spaceborne and airborne platforms. In such linearly polarized SAR(LP-SAR) systems, Faraday rotation in the ionosphere and platform posture will contribute tothe system noise. Therefore to improve this situation, currently a novel Circularly PolarizedSynthetic Aperture Radar (CP-SAR) sensor is developed in Microwave Remote SensingLaboratory, Chiba University. Moreover, from this research, a new backscattering data basedon circularly polarized wave in the remote sensing field can be obtained. As an early stage ofthe development of this CP-SAR sensor, we built an Unmanned Aerial Vehicle (UAV)platform for testing CP-SAR sensor capabilities. In this paper, we describe the novel CP-SARsensor and the method to design CP-SAR UAV especially in estimating the requirement ofdata memory capacity. Also a smaller antenna is possible to be implemented since the 3-dBaxial ratio on antenna characteristic becomes the main parameter in this new CP-SARtechnique. Hence, a compact CP-SAR sensor onboard a small and low cost spaceborneplatform yielding a high accuracy SAR image data can be realized in the near future
MONITORING OF LAND USE CHANGES USING AERIAL PHOTOGRAPH AND IKONOS IMAGE IN BEDUGUL, BALI
No full textThere was change of expending land use in Bedugul. It is necessary to monito the change of highland of Bali, catchments area of Beratan, Buyan and Tamblingan lakes. In order to control land use change and to anticipate degradation of hydrology function of this area. This study is to monitor the land use change by remote sensing and GIS technique. To evaluate land use and land cover, aerial photograph imagery and Ikonos imagery were used. Over 22 years of observation (1981-2003), there was land use changes in the catchments area of Beratan, Buyan and Tamblingan lakes at Bedugul area. The area of settlement increased by 62.6 ha, dry land vegetable crops and forest decreased by 116.5 ha and 32.5 ha, respectively. The surface area of Buyan Lake was also decreased, due to sedimentation caused by erosion in the vegetables dry land crops. Planning the land use study on erosion and soil-water conservation in this area necessary, in order to control land use change, erosion, and sedimentation in the lakes
ENVIRONMENTAL QUALITY CHANGES OF SINGKARAK WATER CATCHMENT AREA USING REMOTE SENSING DATA
No full textLake Singkarak in west Sumatera is currently in very poor condition and become one of the priorities in the government lake rescue program. High sedimentation rate from soil erosion has caused siltation, decreasing of quality and quantity of lake water. Monitoring of the environment quality changes of the lake and its surrounding are required. This study used Landsat and SPOT satellite data in periods of 2000-2011 to evaluate environmental quality parameters of the lake such as land cover, lake water quality (total suspended solid), water run-off, and water discharge in Singkarak lake catchment area. Maximum likelihood classifier was used to obtain land cover. Total suspended solid was extracted using Doxaran algorithm. The look up table and rational method were used to estimate run-off and water discharge. The results showed that the decreasing of forest area and the increasing of settlement were consistent with the increasing of average run-off and water discharge in Paninggahan and Sumpur sub-catchment area. The results were also consistent with the increasing of TSS in Singkarak lake, where TSS increased from around 2-3 mg/l up to 5-6 mg/l in the periods of 2000-2011
IDENTIFICATION OF FISHERY RESOURCES IN MADURA STRAIT BASED ON THE IMPLEMENTATION OF POTENTIAL FISHING ZONE INFORMATION FROM REMOTE SENSING
No full textSpatial information of Potential Fishing Zone (PFZ) was used to identify the prospective location in the Madura Strait, where the fishermen from Fish Landing Port (FLP) around the Madura Strait conducted fishing activities. PFZ was aimed to determine fishing location, to identify the type of pelagic fish resources which were dominantly caught in the MAdura Strait. Fish resources data were obtained by observing the FLP in the east of Madura Strait especially in Pondok Mimbo, Jangkar, Besuki, Probolinggo, Pamekasan, and Sumenep. Based on the application of PFZ spatial information and observation, the types of pelagic fish caught on west monsoon were dominated by Euthynnus spp, Decapterus spp, Ratsrellinger spp, and Trichiurus spp. In the first transition season, types of fish resources were a mix between Euthynnus spp, Decapterus spp, Rastrellinger spp, Sardinella longiceps, and Trichiurus spp, however Sardinella longiceps were still dominated the catches. During the east monsoon fish resources at the Madura Strait was also dominated by Sardinella longiceps. This condition occurred until the second month of the second transition season followed by the mixing among Sardinella longiceps, Euthynnus spp, Decapterus spp, Rastrellinger spp and Trichiurus spp. Keywords: Fish Landing Port, NOAA-AVHRR, Potential fishing zon
PROGRESS FOR STABLE ARTIFICIAL LIGHTS DISTRIBUTION EXTRVCTION ACCURACY AND ESTIMATION OF ELECTRIC] POWER CONSUMPTION BY MEANS OF DMSP/OLS NIGHTTIME IMAGERY
No full textThe Noise Reduction Filter (NRF) that is developed by the authors is applied to extract artificial nightlight components of a time series DMSP/OLS-VIS dataset. High frequency components from the time series DMSP/OLS-VIS dataset are exhausted and a direct current component is extracted by the NRF that is one of the Fourier analysis techniques. The inference of cloud and other disturbance noise are also removed, and a stable artificial nightlight is extracted by the NRF filtration. The intensity value in high power light areas observed by DMSP/OLS-VIS is saturated because of narrow dynamic range of the sensor gain. A simple model called "Deltaic Model" developed by authors corrected those saturated value. Verification of the accuracy of correction methods above described is carried out by comparison with electric power consumption of the calculated values from the model and statistical ones of each prefecture in Japan. Correlation of the values is satisfactory as shown R2 = 0.725. The results of this work shows the remote sensing method by using the DMSP/OLS-VIS nighttime imagery with the correction methods above described is useful to estimate the electric power consumption through a year of fixed areas
DERIVATION OF POPULATION DISTRIBUTION BY COMBINING CENSUS AND LANDUSE DATA: AS AN INPUT FOR TSUNAMI RISK AND VULNERABILITY ASSESSMENT
No full textInformation on population distribution is crucial in distater risk management. Every disaster such as flood, drought, volcanic eruption, storm, earthquake and tsunamis implies theats to people with respect to loss of live, injury, and misery. Therefore, the information on detailed population distribution in the disaster or hazard zone is important in order to mitigate the impact of natural disasters. Moreover, accurate information on people exposure will help the goverment to improve the evacuation planning and to decrease the amount of people at risk. The available information on population distribution is mostly based on statistical data related to administrative boundaries, e.g. village, municipal, district, province, or national level. Within the border of adsministrative boundaries, the population is assumed to be distributed homogeneously within each unit area, even in the part of uninhabited areas e.g. lakes, forest, swamps, and areas with high slopes. Hence, this research focuses on the improvement of the available data on population distribution for the area along the west coast of Sumatera, south coast of Java and Bali. The results were used as an input for the tsunami risk assessment in the framework of the German-Indonesia Tsunami Early Warning System (GITEWS) project. Keyword: People distribution, spatial improvement, tsunami, remote sensing and GIS
SPATIAL MODELING FOR MARICULTURE SITE SELECTION BASED ON ECOSYSTEM PARAMETERS AT KUPANG BAY, EAST NUSA TENGGARA INDONESIA
No full textThe aims of the study were : a. to identify the physical, chemical and biological parameters at the utilization zone-coastal water of Kupang Bay, East Nusa Tenggara, b. to analyze the value of coastal water suitability from the physical, chemical and biological parameters for the development for maniculture at the utilization zone of Kupang Bay, East Nusa Tenggara, c. to select the sub zone for the sea weed culture, grouper fish culture site using the system of floating net cage and the culture of pearl oyster. The method used in the study is a spatial approach by conducting the direct measurement of the physical, chemical, and biological parameters. Mapping and spatial model was processed and analyzed through a geo-statistic method. The site selection for mariculture sub-zones were constructed through a spatial scoring and spatial interaction-RGB model and based on matrix of ecosystem parameters suitability score and weighting. With consideration that any numerical, mathematical or spatial model related to the surface of the earth or an ecosystem should take into account the concept of 4D function of its spatian distribution (x,y,z)and temporal consideration (time) such as seasonal data. The result showed that the range values of the physical, chemical, and biological parameters at utilization zone of the Kupang Bay are as follow: 1. Variable of physical parameters were: a). depth 5-25 m, b). transparancy 3.00-11.00 m, c). temperature 26-28.45 degree of celcius, d). salinity 31.50-38.20 ppt, e). substrate consist of: sand, sandy clay, clay sand, silt clay, silt, sand, and coral, f). current velocity 0.059-0.238m per s, and g). total suspended solid 180-305mg per l. 2. Variable of chemical parameters were: a). dissolved oxygen 6.85-8.74 ppm, b). pH 7.97-8.59, c). phosphate is 0.081-0.435mg per l, and d). nitrate 0.145-4.134 mg per l, 3. Variable of biological parameter were: a). abundance of phytoplankton 106,760-210,380 cell per l, and b). chlorophyll-a 0.033-0.037 mg per m. Sub zone for seaweed culture identified mainly almost at all area of the middle of the Kupang Bay width about 7,544 hectares. The most-suitable sub-zone for grouper fish culture was 2,803 hectares wide and width of 1,336 hectare of moderately-suitable. Sub zone for pearl culture exist especially at the north part of Kupang Bay and at some area nearby at the mouth of the Kupang Bay wide about 4.383.8 hectares. The approach with the above concept had proved that with a significance difference of scoring-weight on each specific and important ecosystem parameters for each spatial analysis purposes (i.e.50 percent scoring-weight of nitrate and phosphate for sea weed culture sub zone; 40 percent scoring-weight of dissolved oxygen for fish culture sub zone and 40 percent scoring weight of plankton abudance for oyster pearl culture sub zone), had resulted in a distinctive and specific delineation for each culture sub zones, thus avoiding and less on sub zonal overlapping
Observations of Ionospheric Conditions Over Pontianak During The Partial Solar Eclipse
No full textSolar energy plays a significant role in creating ionospheric layers through photoionization. However, when a solar eclipse occurs, the ionizing radiation from the sun will be obstructed by the moon, resulting in a decrease in ionization processes and a depletion of ionospheric plasma density. Our research examines the effects of two partial solar eclipse events that occurred on December 26, 2019 (Eclipse 1) and April 20, 2023 (Eclipse 2) over Pontianak. We observed changes in foF2 and TEC during these events. Our observations show that foF2 and TEC decreased at the start of a partial eclipse but returned to normal once the eclipse ended. The maximum decrease in foF2 observed was 1.88 MHz for Eclipse 1 and 1.26 MHz for Eclipse 2, while the decreases in TEC were 5.68 and 12.81 TECU for Eclipse 1 and 2 respectively. We noted that geomagnetic activity was quiet during both eclipses, indicating that the reduction in ionospheric parameters (TEC and foF2) is affected by the solar eclipse. During a solar eclipse, the decrease in ionization intensity results in a reduction in electron numbers in the ionospheric layers, leading to a reduction in TEC and foF2
A Review: Flight Envelope Monitoring and Protection as One of the Flight Safety System
No full textThe development of civil aircraft technology, especially commercial aircraft, is now very advanced and complex. This development is intended to assist the pilots to control aircraft in various flight conditions with the main goal to achieved is flight safety. This literature review will discuss research on the flight warning system, which will support the flight envelope protection system development study, which has been conducted over the past few years. The review includes an analysis of existing literature, case studies of aviation accidents, and the evaluation of flight envelope protection systems in current aircraft models. This review shows that the development of technologies and systems can make a significant contribution to flight safety and pilot situational awareness of flight envelope boundaries, so the possibility of aircraft accidents due to loss of control can be reduce
