Judul: Eksternalitas Negatif Pencemaran Sungai Kampar Akibat Kegiatan Penambangan Emas Tanpa Izin (PETI)
Abstrak: One of the natural resources utilization can be conducted from mining sector, both in a legal and illegal. One of the mining common conducted by the society is Gold Mining without Authorization (PETI). Generally, people conduct the PETI activity in a river, that will bring negative impacts such as water and soil contamination, also have negative damage both healthy and the ecosystem of resources. PETI has been threaten for people life which utilize river as the place to fulfill their daily needs. This research has been conducted to determine the negative externality perceived by the people through Kampar River contamination as the impact of illegal golden mining activities. The specific objective of this research was to describe the PETI activity in Kampar River, to identify the negative externality perceived by the people through river contamination as the impact of PETI activity, and to estimate PETI eligibility to pay for the eradication of Kampar River contamination. The method used in this research was the descriptive analysis and estimate the value of Willingness to Pay (WTP) by the miner with the CVM approaching method. The sampling conducted by purposive sampling method from people lived around Kampar River, PETI miner and stakeholder. The result of this research showed that PETI activity had been conducted since 2008 with the total miner of 150 people. PETI effect the negative externality perceived by the people live around Kampar River. The miners were eligible to pay the cost for the eradication of river contamination. The average estimated value of WTP in small scale miner was Rp 34 999 per mining per person and big scale miner was Rp 50 000 per mining per person. There were 4 factors affect the amount of WTP value there were age, revenue level, family responsibility number and time for the miner stayed
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Judul: Kerugian Ekonomi akibat Konversi Lahan Perkebunan Kelapa Sawit menjadi Pertambangan Emas (Studi Kasus: Desa Daya Murni, Kecamatan Pelepat Ilir, Kabupaten Bungo, Provinsi Jambi)
Abstrak: The increasing of people amount will effect on the demand, to fulfill those needs it increase the extraction towards resources in some more amount. one of the economic activities to fulfill those needs is a mining business are carried out by converting oil palm plantation. The mining activities are mining without authorization (PETI). This research objective were to identify the perception of multistakeholder about PETI activity, to estimate the economic loss because land convertion, and to analyze the willingness to pay (WTP) for of miner society. This research used descriptive analysis, loss of earning method, contingent valuation method (CVM), and multiple linear regression. The result showed that the multi stakeholder perception related to PETI from the aspect of social, economic, and environmental. The impact socio-ekonomic aspect are opening job, increase income, mining accidents, and the constriction plantation. While the impact of environmental aspect is the destruction of soil structure, reduce soil fertility, land became irreguler, and the destruction of village and plantation roads caused by sund truck. Economic loss from production of palm oil is Rp 2066 333.3/people/month. The total value of WTP miner is Rp 315 000 with an average of Rp 10 150. The factors affect on the WTP were the amount of amenability, income, soil quality, the dummy mine work and other work.
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Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix