Judul: Customer Attitude and Satisfaction by Online Application for Ready-to-Eat Food Delivery Service in Jabodetabek
Abstrak: Pandemi Covid-19 membuat masyarakat harus lebih berusaha untuk bertahan hidup. Khususnya warga sekitar Jabodetabek yang terdampak PSBB mengakibatkan mobilisasi masyarakat menjadi terbatas dan aplikasi daring membantu pelanggan untuk membeli makanan. Tujuan dari penelitian ini adalah menganalisis proses keputusan pembelian, sikap dan kepuasan pelanggan serta menguji perbedaan secara nyata pada sikap dan kepuasan pelanggan. Analisis deskriptif digunakan untuk proses keputusan pembelian pelanggan. Analisis Multiatribut Fishbein digunakan untuk menganalisis sikap pelanggan dan kepuasan pelanggan pada penelitian ini menggunakan analisis CSI. Serta penggunaan uji beda nonparametik Mann-Whitney. Hasil penelitian menunjukkan bahwa terdapat lima proses keputusan pembelian, nilai sikap terhadap pelanggan aplikasi GrabFood lebih besar dibandingkan GoFood dengan poin 193,88 dan 193,86. Diperoleh sikap dan kepuasan pelanggan GoFood dan GrabFood tidak berbeda secara nyata, serta pelanggan dianggap puas dengan nilai CSI GoFood dan GrabFood sebesar 79,24% dan 78,16%., The Covid-19 pandemic has forced people to do more to survive. In particular, residents around Jabodetabek who were affected by the PSBB resulted in limited community mobilization and online applications helping customers to buy food. The purpose of this study are to analyze the purchasing decision process, attitudes and customer satisfaction and to test whether there is a significant difference in attitudes and customer satisfaction. Descriptive analysis tools are used for the customer's purchasing decision process. Fishbein Multiattribute Analysis is used to analyze customer attitudes and customer satisfaction in this study using CSI analysis. And the use of the Mann-Whitney nonparametric difference test. The results show that there are five purchasing decision processes, the attitude value towards GrabFood application customers is greater than GoFood with 193.88 and 193.86 points. The attitudes and satisfaction of GoFood and GrabFood customers were not significantly different, and customers were considered satisfied with the CSI GoFood and GrabFood values of 79.24% and 78.16%, respectively.
Keyword: Customer Satisfaction Index, Mann-Whitney, Online Application, Fishbein Multi-attribute

Judul: Analysis of Student Satisfaction towards Online Food Delivery Services during COVID-19 Pandemic
Abstrak: Pelaku bisnis di Indonesia mulai menjadikan internet sebagai alat penunjang kegiatan bisnis mereka karena dapat mempermudah hubungan bisnis dengan pelanggan secara lebih luas dan efisien. Selama kondisi pandemi COVID- 19, ada peningkatan aktivitas jual beli yang dilakukan secara daring dan menjalankan prinsip pengantaran, terutama untuk sektor restoran. Penelitian ini bertujuan untuk mengetahui tingkat kepuasan dalam dua perusahaan yang menyediakan layanan jasa antar makanan. Penelitian ini menggunakan data primer dari 108 responden mahasiswa IPB yang melakukan pembelian secara daring. Metode analisis yang digunakan adalah analisis deskriptif, importance performance analysis (IPA), dan customer satisfaction index (CSI). Hasil penelitian menunjukkan bahwa tingkat kepuasan pada jasa pesan antar makanan secara daring diantaranya disebabkan oleh pelayanan yang diberikan oleh driver. Berdasarkan hasil analisis metode IPA, perusahaan penyedia layanan jasa pesan antar makanan perlu meningkatkan kinerja pada atribut-atribut yang memiliki tingkat kepentingan tinggi namun tingkat kinerjanya rendah, diantaranya atribut harga yang lebih rendah, lokasi dan harga promo., Businesses in Indonesia are starting to use the internet as a tool to support their business activities because it can facilitate business relations with customers more broadly and efficiently. During the COVID-19 pandemic, there has been an increase in online buying and selling activities and implementing the principle of delivery, especially for the restaurant sector and the food business, where orders can be made boldly. This study aims to determine the level of satisfaction in the two companies that provide food delivery services. This study used primary data from 108 IPB student respondents who made bold purchases. The analysis method used were descriptive analysis, importance performance analysis (IPA), and customer satisfaction index (CSI). The results showed that the level of satisfaction in the two companies was due to the services provided by the driver. Based on the results of the analysis of the important performance analysis method (IPA), food delivery service companies that can improve performance on attributes that have a high level of importance but have low levels of performance, include lower price attributes, location and promo prices.
Keyword: consumer satisfaction, COVID-19, food products, online shopping

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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