Judul: Analysis of the Economic Benefits of Community-Based Waste Management (Case Study: Sindara Berkah Waste Bank, Gunung Batu Village, Bogor City)
Abstrak: Bank sampah merupakan contoh strategi pengelolaan sampah yang berfokus pada konsep 3R (reduce, reuse, recycle). Salah satu bank sampah yang ada di Kelurahan Gunung Batu, Kota Bogor adalah Bank Sampah Sindara Berkah. Jumlah nasabah yang berpartisipasi di Bank Sampah Sindara Berkah dinilai masih rendah karena kurangnya kesadaran akan pentingnya mengelola sampah. Penelitian ini bertujuan (1) Mengidentifikasi sistem pengelolaan sampah di Bank Sampah Sindara Berkah, (2) Menganalisis persepsi nasabah terkait pengelolaan sampah di Bank Sampah Sindara Berkah, dan (3) Menganalisis manfaat ekonomi dari pengelolaan sampah di Bank Sampah Sindara Berkah. Metode yang digunakan pada penelitian ini adalah analisis deskriptif kualitatif dan kuantitatif, serta analisis pendapatan. Hasil penelitian ini menunjukkan sistem pengelolaan yang dijalankan oleh bank sampah masih dikategorikan sederhana. Persepsi nasabah terhadap Bank Sampah Sindara Berkah sangat baik. Hasil perhitungan dari analisis pendapatan sebesar Rp 668.800,00. Hasil akhir analisis menunjukkan bahwa keberadaan bank sampah memberikan manfaat kepada nasabah terutama nasabah Bank Sampah Sindara Berkah., The waste bank is an example of a waste management strategy with the 3R concept (Reduce, reuse, recycle). One of the waste banks in Gunung Batu Village, Bogor City is the Sindara Berkah Waste Bank. The number of customers participating in the Sindara Berkah Waste Bank is considered low due to a lack of awareness of the importance of managing waste. This study aims (1) to identify the waste management system at the Sindara Berkah Waste Bank, (2) to analyze public perceptions regarding waste management at the Sindara Berkah Waste Bank, and (3) to analyze the economic benefits of waste management at the Sindara Berkah Waste Bank. The method used in this research is descriptive qualitative and quantitative analysis, as well as income analysis. The results of this study indicate that the management system run by the bank is still categorized as simple. The public perception of the Sindara Berkah Waste Bank is very good. The result of the calculation from the income analysis is IDR 668.800.00. The final result of the analysis shows that the existence of the waste bank provides benefits to the community, especially the customers of the Sindara Berkah Waste Bank.
Keyword: likert, partistipasi,, partistipasi, pendapatan, persepsi, sampah anorganik, income, inorganic waste, likert, participation, perception

Judul: Economic Benefits and Sustainable Waste Management Strategies (Case Study: RW 08 Merbabu Waste Bank, Larangan Village, Harjamukti District, Cirebon City).
Abstrak: Pengelolaan sampah membutuhkan paradigma baru yang lebih banyak melibatkan partisipasi masyarakat dan lebih menekankan pengurangan sampah dari sumbernya. Bank sampah menjadi salah satu kegiatan yang bisa membantu pengurangan sampah. Pelaksanaan operasional bank sampah memiliki kendala internal maupun eksternal, salah satunya adalah wabah pandemi COVID-19. Penelitian ini bertujuan menghitung manfaat ekonomi bank sampah sebelum dan saat awal pandemi COVID-19 yaitu tahun 2019 dan 2020 menggunakan pendekatan analisis pendapatan, menganalisis pola perilaku nasabah menggunakan analisis deskriptif dan mengukur persepsi nasabah terhadap kinerja bank sampah dari aspek ekonomi, sosial dan lingkungan menggunakan skala likert, serta penyusunan strategi keberlanjutan bank sampah menggunakan Analytical Hierarchy Process (AHP). Hasil penelitian menunjukkan manfaat ekonomi yang diperoleh Bank Sampah RW 08 Merbabu dari tahun 2019 hingga 2020 mengalami penurunan yaitu Rp. Rp 547.200 per tahun menjadi Rp. Rp153.500 per tahun atau menurun sebesar 71,9%. Meskipun ada pandemi COVID-19, hanya sedikit nasabah yang mengalami perubahan motivasi dalam pemilahan sampah. Secara keseluruhan Bank sampah RW 08 Merbabu sudah memberikan dampak dari aspek ekonomi, sosial dan lingkungan kepada nasabah. Strategi pengelolaan bank sampah yang berkelanjutan dapat dicapai melalui peningkatan sosialisasi dan promosi keberadaan bank sampah lebih sering kepada masyarakat di RW sekitar., Waste management requires new paradigm that involves more communities participation and emphasizes reducing waste at source. Waste bank is one of the activities that can help waste reduction. The implementation of waste bank operations has internal and external constraints, one of them is COVID-19 pandemi. This study aims to calculate the economic benefits of waste banks before and at the beginning of the COVID-19 pandemi in 2019 and 2020 using an income analysis approach, to analyze behavior patterns and perceptions of waste banks customer using descriptive analysis, to measure the performance of waste banks from the economic, social and environmental aspect through Likert scale, to formulate strategies for waste bank sustainability using the Analytical Hierarchy Process (AHP). Based on the result, the economic benefits obtained in RW 08 Merbabu Waste Bank from 2019 to 2020 was decreased from Rp. IDR 547,200 per year to IDR. Rp153,500 per year (71.9%). Despite the COVID-19 pandemi, only a few customers experienced a motivation change in sorting waste. Overall, the Waste Bank RW 08 Merbabu has given impact on customers from economic, social and environmental aspects. Sustainable waste bank management strategy can be achieved through increasing socialization and promotion of the existence of waste banks more often to the surrounding area.
Keyword: Analytical Hierarchy Process, income analysis, perception, behavior pattern

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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