Judul: Kajian Perubahan Tutupan Lahan Sub DAS Citanduy Hulu terhadap Kualitas Air Sungai Citanduy Hulu
Abstrak: Along with the growth of population, the need of areas for residential is also increasing which interfere the existence of forest along the river upstream areas. Land use changes which occured on the watershed indicates the decrease of water quality for example in Citanduy Hulu subwatershed. The aim of this research is to assess the changing of land cover, water quality and the relation between both aspects. Analysis which was used in this research are changes of land cover, and Index of Water Quality-National Sanitation Foundation (IKA-NSF) calculation. Land cover type in Citanduy Hulu subwatershed which decreased are forest (33.27%), bushes (45.25%), and waterbody (47.59%). Land cover type which increased are residential (107.88%), paddyfield (98.52%), dryland farming (26.97%), and open space (74.02%). The water quality of Citanduy Hulu river is categorized as good. The value of IKA on Citanduy Hulu river showed the tendency to decline from 73.16 in 2003 to 70.42 in 2011. The decrease of forest, bushes, and waterbody also the increase of residential, paddyfield, dryland farming and open space at Citanduy Hulu subwatershed caused the decrease of water quality at Citanduy Hulu river.
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Judul: Pengaruh Perubahan Tutupan Lahan dan Pemanfaatan Sumberdaya Air terhadap Kualitas Air Sungai di Daerah Aliran Sungai Cisadane Segmen Hulu
Abstrak: Increasing the number of residents in the Cisadane watershed area upstream segment cause high river water use and land cover changes. This negative impact on the incidence of pollution load and the source of pollutants/waste that may affect the water quality of rivers and indirectly affect the level of river water pollution. The water quality is very depend on the effort to meet the needs of water for each utility. Therefore, research on the effects of land cover change and water resources utilization of river water quality in the Cisadane watershed upstream segment needs to be done. This research was conducted in the Cisadane watershed area upstream from June to August 2009. Equipments used, such as water quality data, land cover, population, utilization of river water, debit, and livestock. The instrument used is a Arcview 3.2 program and MINITAB release 14. Data processing is done by analysis of land cover change, analysis of changes in water quality, pollution load, pollution load carrying capacity, the analysis of public understanding, and study the influence of land cover changes on water quality. During the period 2005-2008 land cover changes in the Cisadane watershed area upstream shown by the decrease of forest area (72.88%), shrubs (88.18%), open land (91.14%), and the fields ( 97.52%), and increasing plantation area (102.46%), and residential (34.21%).Utilization of river water in the Cisadane watershed area upstream was quite high. For 93% of the 190 families interviewed using Cisadane River for MCK. Pollutant sources that can be seen is garbage (16%) and wastewater (30%). The dominant pollution load comes from domestic waste (4067.86 tons/month 4129.80 BOD and TSS) and livestock waste (3.24 tons/month of BOD and 17.05 tons/month TSS). This pollution load exceeds the capacity for BOD pollution load of each month and it ranged from 2484 tons/month to 3801 tons/month, while for TSS pollution load capacity not exceeding pollution load for each month. Changes in land cover and use of river water affects river water quality. This can be demonstrated by increasing in TDS (18 mg/l), BOD (20.8 mg/l), phosphate (0.303 mg/l), and COD (38 mg/l) which tends to exceed water quality standards. If viewed based on key parameters of water quality (BOD, COD, TSS), the correlation of test results on the α level 0.1 also could be concluded that there is a relationship between changes of land cover with water quality, although the significance level is relatively small. The icreasing of water quality parameters caused the decrease of Water Quality Index from 85,58 to 73,66, but the condition of the waters is still relatively moderate to good.
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Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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