Judul: Penentuan Karakteristik Akifer dan Potensi Airbumi di Jakarta
Abstrak: Groundwater is one of the water resources used for domestic and industrial water uses, particularly in Jakarta region. Excessive extraction of groundwater has caused groundwater depletion and land subsidance. This study aimed to determine the characteristics of aquifer and groundwater potential of the Jakarta region based on available geologic logs and well data, including pumping test data. Analysis of geological log indicated that Jakarta region had several layers of confined aquifer namely aquifer 20 – 30 m below ground and another aquifer 50 – 170 m below the ground surface. Analysis result of the pumping test data from 14 production wells in Jakarta region indicated transmisivity value ranged from 5 to 522.8 m2/days, while the values of hydraulic conductivity of the aquifer system in Jakarta region ranged from 0.62 to 58.09 m/day. Hydraulic conductivity values indicated that the rock types of aquifer in Jakarta region were dominated by fine sands and clay. From the aquifer characteristic, potential groundwater in Jakarta region ranged from 5 to 522.8 m3/day/ meter aquifer. Groundwater potential of each well in Jakarta region was still not fully utilized due to improper pumping construction in positioning the well –screen-, where was not installed properly on aquifer layers but on clay layers, so the well efficiency become low with the consequences of high operation costs.
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Judul: Kajian Potensi dan Supply-Demand Airbumi di Kecamatan Citeureup, Kabupaten Bogor
Abstrak: Human life creature else cannot life without groundwater. In Citeureup subdistrict, groundwater utilization for industry and housekeepinGunung Groundwater utilization need be increasinGunung Whereas groundwater availability be limited by nature condition in this area. Highly productive aquifer in Citeureup subdistrict is obtained from the alluvium river deposits, mainly a long both sides of Citeureup rivers, Cileungsi rivers, and Cijere riverSungai Well yield ranges between 2 and 5 l/sec in sand and gravel deposits with intergranular groundwater flow. Good quality of groundwater still found both in shallow and depth of aquifer. Based on quantity and quality of groundwater, the management of supply demand balance must be done. This study to give description about availability and demand of groundwater for supporting activity in Citeureup subdistrict.
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Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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