Judul: Hujan asam dan perubahan kualitas air sumur di wilayah industri (studi kasus di Wilayah Industri Cibinong-Citeureup Kabupaten Bogor)
Abstrak: The industrial area of Cibinong-Citeureup Bogor is crowded with transportation, has dusty atmosphere, has many industries, and has been experienced acid rain in 2008. Total of industries are 2944 units and the population density is 4131 people km-2. About 75.63 % of people in this area consume well water for drinking. Acid rain intensity and distribution was studied to map and to calculate the rate of well water quality degradation. Well water quality was monitored from the year of 1995, 1999, 2001, 2006, 2008, and 2009. The quality of rain water was monitored from the year of 1999, 2001, 2006, 2008, and 2009. The parameters studied were: pH, NO3-, SO4=, Fe, and Ca. The rain water was collected from 16 locations for the first 30 minutes of rain fall onset. The well water was sampled from 16 locations. The result showed that the pattern of acid rain was distributed into two categories: The first, is the area that has experience continuous high intensity acid rain (pH<5.0) covering ±1800 ha, whilst the second is the area that has rarely experienced high intensity acid rain. In the first area category the acid rain has influenced the well water quality degradation. The pH of acid rain has influenced the well water acidity. The NO3- concentration in well water was increased significantly (Fcal 1.61<Ftable; P 0.193<α 0.05). On the contrary, the concentration of SO4= in well water decreases although was not significantly different (Fcal 0.73<Ttable , and P 0.540 > α0.05). Furthermore, the Fe and Ca of well water was increased significantly (P 0.049 for Fe and P 0.001 for Ca) from 1999 to 2009. In the second category area the acid rain has not influenced the well water quality.
Keyword: West Java, Water quality, Dry deposition, Wet deposition

Judul: Kualitas air sungai Citeureup-Cileungsi dan kaitannya dengan buangan limbah cair industri
Abstrak: Penelitian ini bertujuan untuk mengidentifikasi kualitas air Sungai Citeureup-Cileungsi dan kaitannya dengan buangan limbah cair industri. Hasil penelitian ini diharapkan dapat bermanfaat sebagai bahan pertimbangan dan masukan dalam menentukan kebijakan pengelolaan lingkungan Sungai Citeureup-Cileungsi. Penelitian ini dilakukan dengan mengumpulkan dan mengkaji data sekunder mengenai cualitas air Sungai Citeureup-Cileungsi selama periode tahun 2001-2002, debit air Sungai Citeureup-Cileungsi selama periode tahun 2000-2002, dan effluent industri selama periode ahun 2001-2002. Data kualitas air sungai dan effluent industri diperoleh dari Dinas Tata Ruang dan Lingkungan Hidup (DTRLH) Kab. Bogor; sedangkan data debit air diperoleh dari Dinas Binamarga dan Pengairan Kab. Bogor dan Perum Jasa Tirta II. Selain pengumpulan data sekunder dilakukan peninjauan langsung ke lapangan dan pengecekan titik lokasi sampling kualitas air sungai serta titik lokasi masing-masing industri dengan menggunakan GPS (Global Positioning System) Analisis data kualitas air Sungai Citeureup-Cileungsi dilakukan dengan dua pendekatan, yaitu analisis kualitas air berdasarkan perbandingan baku mutu dan analisis dengan menggunakan metode IKA-STORET. Baku mutu yang dijadilan acuan dalam penelitian ini adalah baku mutu Gol. B:C;D (berdasarkan SK Gub Jabar No. 38/1991) serta aku mutu Kls. I, Kis. II, Kls. III, dan Kls. IV (berdasarkan PP RI No. 82/2001). Sedangkan analisis data untuk mengetahui kontribusi buangan limbah cair industri dilakukan dengan perhitungan beban (load) pada ruas-ruas sungai tertentu. Parameter kualitas air sungai yang dianalisis pada penelitian ini meliputi 24 parameter, yaitu subu, TDS, kekeruhan, DHL, pH, DO, NH, N, NO-N, NO3-N, Cl₂, Cr, Hg, Fe, Mn, Zn, Cu, Pb, Cd, CN, fenol, minyak dan lemak, senyawa aktif biru metilen/MBAS (deterjen), fecal coliform, serta total coli. Sedangkan parameter beban limbah cair industri yang dihitung Ja penelitian ini adalah BOD,, COD, dan TSS. Sebanyak 50% dari seluruh parameter yang diukur diatas ternyata telah melampaui bak butu Gol. B;C;D; parameter-parameter tersebut meliputi: TDS, NH-N, NO₂-N, NO,-N, Hg, Zn, Cu, Cd, fenol, minyak dan lemak, serta MBAS. Jumlah parameter yang telah mutampaui baku mutu Kls. I adalah sebanyak 50% dari seluruh parameter yang diukur,
Keyword: buangan limbah cair industri, Global Positioning System, Spatial Planning Environment

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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