Judul: All You Can Eat Restaurant: Food Waste and Reduction Efforts
Abstrak: Food waste mendominasi jumlah timbulan sampah di Indonesia. All You Can Eat (AYCE) Grill & Shabu merupakan restoran buffet yang memiliki banyak peminat di Jakarta, sekaligus potensial menjadi penyumbang food waste secara masif. Penelitian ini bertujuan untuk mengidentifikasi karakteristik responden pada Tent Suki & BBQ Rawamangun dan strateginya dalam mengurangi food waste, melalui analisis deskriptif kualitatif. Selanjutnya, faktor yang memengaruhi food waste konsumen juga dianalisis melalui regresi linear berganda dan tabulasi silang. Berdasarkan hasil penelitian, responden Tent Suki & BBQ Rawamangun dodiminasi oleh Gen Z berjenis kelamin perempuan dan sarjana dengan pendapatan di bawah atau setara UMR Jakarta 2023. Selain itu, mayoritas responden pernah berkunjung ke restoran AYCE dengan frekuensi 2 kali dalam 3 bulan terakhir. Dalam mengatasi food waste, Tent Suki & BBQ Rawamangun memiliki strategi pencegahan food waste pada tahap pemrosesan, kebijakan denda dan durasi makan bagi konsumen, serta pemanfaatan minyak jelantah bersama mitra restoran. Faktor-faktor yang memengaruhi jumlah food waste konsumen Tent Suki & BBQ Rawamangun adalah jenis kelamin, tingkat pendidikan terakhir, dan pendapatan total per bulan., Food waste dominates the amount of waste generated in Indonesia. All You Can Eat (AYCE) Grill & Shabu is a buffet restaurant that has many enthusiasts in Jakarta, along with the potential of large food waste contribution. This study aims to identify the characteristics of respondents at Tent Suki & BBQ Rawamangun and their strategies in reducing food waste, through qualitative descriptive analysis. This study utilizes multiple linear regression and cross-tabulation to analyze the factors that influence consumer food waste. The results show that bachelor female Gen Z with income below or equivalent to Jakarta 2023 minimum wage dominate the respondents of Tent Suki & BBQ Rawamangun. In addition, the majority of respondents had visited the AYCE restaurant with a frequency of 2 times in the last 3 months. In dealing with food waste, Tent Suki & BBQ Rawamangun has a food waste prevention strategy at the processing stage, policies for consumers, and utilization of used cooking oil with restaurant partners. The amount of food waste generated by consumers of Tent Suki & BBQ Rawamangun is influenced by gender, education level, and monthly income.
Keyword: buffet, denda, food waste, konsumen, rumah makan

Judul: Estimasi Nilai Kehilangan Food waste dan Potensi Implementasi Denda Sisa Makanan di Rumah Makan (Studi Kasus : Grand Garden Café & Resto, Kebun Raya Bogor).
Abstrak: Bogor Botanical Garden has the most tourist visits amongst the other nature tourism sites in Bogor City. Most tourists spend almost 40% of their budget on food while traveling, and 50% of restaurant’s income earned from tourists. An eating out habit as a lifestyle has been increasing the volume of food waste while 93% of organic waste in Indonesia comes from food wasted. In this case, it’s hard to avoid food wasting because it’s related with habits but food waste causes environmental and economic loss because of the pollution and waste of resources along the production. Therefore, it needs a food waste prevention to support Zero Waste 2030 program in achieving SDGs number 12. The purposes of this research are (1) to k9ow the perceptions and behaviours of restaurant’s consumers about food waste; (2) to estimate the amount and loss value of food waste generated in resto; (3) to analyse the potential implementation of fines system for consumer’s food waste. The methods used in this research are descriptive analysis using Guttman, Likert, SNI 10-3964-1994, and Contingent Valuation Method. The results of this research show that knowledge about food waste issues and the confession of having food waste prevention in daily life, cannot ensure someone from wasting food. The high amount of loss value of food waste in restaurant (Rp872.338.472/year) shows the waste of resources that cannot be avoided. Thus, a fines system for consumer’s food waste leftovers can be one of the alternative solutions. The fine scheme based on mean WTP of restaurant’s visitors is Rp15.676 to Rp21.360 per 100 grams of food wasted (applies multiples), while for buffet menu is Rp50.000.
Keyword: food waste, loss value, waste of resource, fine of food wasted, willingness to pay

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.
Keyword: