Judul: Penentuan Nilai Karakteristik Akuifer Sumur Air Tanah Melalui Uji Pemompaan (Pumping Test) Dengan Metode Cooper-Jacob di Leuwikopo, Darmaga
Abstrak: Air merupakan salah satu sumberdaya alam utama yang sangat dibutuhkan oleh seluruh makhluk hidup yang ada di alam semesta ini Tanpa adanya air maka akan terjadi banyak penderitaan dan kesengsaraan. Air permukaan dan air tanah yang umumnya sering dimanfaatkan, walaupun pemanfaatan air tanah (groundwater) belum optimal dibandingkan air permukaan (surface water). Hal ini dikarenakan air permukaan lebih mudah diperoleh dan dimanfaatkan. Akan tetapi, bila dilihat dari distribusi air di bumi tersebut maka air tanah memiliki potensi pemanfaatan yang sangat besar
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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: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model