Judul: Socio-Economic and Environmental Benefits and Participation of Waste Bank Customers during the COVID-19 Pandemic. (Case Study: Rangga Mekar Garbage Bank, South Bogor District, Bogor City)
Abstrak: Penetapan kebijakan PSBB di Kota Bogor telah menyebabkan aktivitas masyarakat lebih banyak dilakukan dari rumah. Dampaknya, timbulan sampah yang berasal dari aktivitas rumah tangga mengalami peningkatan. Oleh karena itu diperlukan peran pengelolaan sampah rumah tangga seperti bank sampah. Salah satu bank sampah yang tetap aktif saat Pandemi COVID-19 adalah Bank Sampah Rangga Mekar. Penelitan ini bertujuan untuk (1) menganalisis tingkat partisipasi nasabah bank sampah terhadap pengelolaan sampah rumah tangga, (2) menganalisis manfaat sosial, ekonomi, dan lingkungan atas keberadaan bank sampah, dan (3) menganalisis faktor yang memengaruhi partisipasi nasabah dalam menabung sampah. Penelitian ini menggunakan metode analisis deskriptif kuantitatif dan analisis regresi Poisson. Hasil penelitian menunjukkan bahwa secara umum tingkat partisipasi nasabah lama dalam pengelolaan sampah rumah tangga tergolong sedang sedangkan nasabah baru masih rendah. Manfaat sosial yaitu penyerapan tenaga kerja, meningkatnya interaksi antar warga, peningkatan soft skill pengurus bank sampah dan pemberdayaan masyarakat melalui kegiatan urban farming. Manfaat ekonomi berupa peningkatan jumlah saldo tabungan dan share pendapatan. Manfaat lingkungan yaitu perbaikan kebersihan dan keindahan lingkungan. Faktor usia, jarak rumah ke bank sampah, jumlah anggota keluarga dan ketersediaan waktu luang mempunyai pengaruh terhadap partisipasi nasabah dalam menabung sampah selama Pandemi COVID-19., The establishment of the PSBB policy in the city of Bogor has caused more community activities to be carried out from home. As a result, the generation of waste originating from household activities has increased. Therefore, the role of household waste management is needed, such as a waste bank. One of the waste banks that remained active during the COVID-19 pandemic was the Rangga Mekar Garbage Bank. This study aims to (1) analyze the level of participation of waste bank customers in household waste management, (2) analyze the social, economic, and environmental benefits of the existence of a waste bank, and (3) analyze the factors that influence customer participation in saving waste. This research uses descriptive quantitative analysis method and Poisson regression analysis. The results showed that in general the level of participation of old customers in household waste management was moderate, while new customers were still low. Social benefits include employment, increased interaction between residents, increased soft skills of waste bank management and community empowerment through urban farming activities. Economic benefits in the form of an increase in the number of savings balances and share of income. Environmental benefits, namely improving the cleanliness and beauty of the environment. Age factors, distance from house to waste bank, number of family members and availability of free time have an influence on customer participation in saving waste during the COVID-19 pandemic.
Keyword: pengelolaan sampah, regresi Poisson, share pendapatan, urban farming

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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