Judul: The Impact Of Water Quality In Healthy Risk Donan River, Cilacap-Central Java
Abstrak: Industrial waste waters will reduce the quality of water since some industry use the river as a waste disposal site and transport the waste into sea waters. Donan estuary has evolved into a new growth center because this area has been used as an industrial hub, the port area, transport and fisheries. Waste waters from natural or anthropogenic activities around Donan river is suggested as the pollution trigger. Large industrial waste producers located in the Donan waters are the oil and gas industry, fertilizer bagging unit, cement mills, workshops shipping, oil mills, industrial refined sugar. Waste generated from these activities has been discharged into the river before transporting into the sea in the form of solid waste, wastewater, and gas. This raises a strong presumption that Donan has been polluted. The purpose of this study are (1) Determine the water quality and heavy metal concentrations of Pb and Cd in water, sediment and P. Erosa in Donan waters (2) Know the status of pollution, pollution load, and the assimilation capacity of Donan waters, (3) Perform a risk analysis of the effects of Pb and Cd pollution on health and risk management of Donan waters pollution control. Research is done by field surveys, direct examination of samples in the field and laboratory, and interviews with parties related to the Donan waters. Observations were made at six stations before industrial activity which head to the estuary area of Segara Anakan. Research was conducted eksitu and insitu by comparing the quality standard based on Government Regulation No. 82 of 2001. The amount of pollutant loads, pollutant index, health risks were determined using the established approaches. The result indicates that the quality of Donan river based on pollution index method medium polluted on station 2,4,6 and mild polluted at the station 1,3,5. The average of tested parameters exceeded the quality standards stipulated by Government Regulation No. 82 of 2001 on water quality class II. Pollution load is calculated based on the parameters of TSS, BOD, COD, Pb, and Cd both in the high tide and low tide conditions, the average COD value of the highest pollutant load per day is 225 tons/day and TSS is 92 tons / day.the pollutant load which entering into the Donan river exceeded its assimilation capacity for the tested parameter. Pb and Cd in the contained intake in water, sediment and selfish in study area were in the level of risk > 1 that means very high risk for human health. It is shown that the level of risk in water, sediment, and selfish is great therefore it is needed to reduce the contact time by reducing the daily or annual exposure time.
Keyword: pollutant load, assimilation capacity, P.erosa, risk health, sediment

Judul: Status Pencemaran Berdasarkan Logam Berat Pb, Hg, Cd, Dan Ag Dalam Air Dan Sedimen Di Estuari Sungai Donan, Segara Anakan Timur
Abstrak: Segara Anakan merupakan suatu laguna yang terletak di Kabupaten Cilacap, Jawa Tengah yang diapit oleh dua daratan yaitu Pulau Jawa dan Pulau Nusakambangan serta dilalui oleh dua kanal, yaitu kanal barat dan kanal timur. Penelitian ini dilakukan untuk menganalisis kandungan logam berat Pb, Hg, Ag, dan Cd serta mengetahui status pencemaran berdasarkan logam berat pada badan air dan sedimen. Penelitian dilakukan melalui survei dan sampling dari Agustus 2015-Januari 2016 di 5 stasiun yang terdapat di estuari Sungai Donan. Berdasarkan hasil penelitian kadar logam yang terdapat di dalam sedimen dan air mengalami fluktuasi tiap bulannya. Indeks pencemaran di wilayah tersebut tergolong ke dalam cemar ringan dan sedang. Berdasarkan nilai risiko potensi ekologi logam berat di sedimen dapat dilihat bahwa Hg>Cd>Pb. Nilai rata-rata ERI berdasarkan hasil perhitungan termasuk ke dalam kategori Low Risk dengan nilai sebesar 50,6724.
Keyword: Air, logam berat, sedimen, Segara Anakan, status pencemaran

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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