Judul: Analysis of Food Choice Motives and Practices Through Online Food Delivery Apps in Bogor Undergraduate Students
Abstrak: Perkembangan dan kecanggihan teknologi telah menyebabkan perubahan gaya hidup masyarakat, salah satunya pemesanan pangan daring pada kalangan anak muda yang dapat mempengaruhi kebiasaan konsumsi pangan. Penelitian ini bertujuan untuk menggambarkan motivasi pemilihan pangan dan praktik pemilihan pangan melalui aplikasi pemesanan pangan daring pada mahasiswa di Kota Bogor sebagai pengguna. Penelitian dilakukan bulan Oktober sampai November 2019, di wilayah Kota Bogor, Jawa Barat. Desain studi berupa cross sectional study dengan penarikan subjek menggunakan metode purposive didapatkan 105 orang subjek. Hasil penelitian menunjukkan bahwa harga merupakan motivasi yang paling dipertimbangkan oleh subjek (mean = 3,60; median = 4,0). Karakteristik subjek, seperti uang saku, tempat tinggal, dan jenis kelamin berhubungan dengan praktik dan motivasi pemilihan pangan. Motivasi harga dan agama memiliki hubungan yang signifikan dengan praktik pemilihan pangan (p = 0,050 dan p = 0,019)., Modern technology has revolutionized and caused changes in people’s lifestyles, one of them is online food delivery among young adults that can affect food consumption habits. This study aimed to analyze food choice motives and food choice practices through online food delivery (OFD) apps in Bogor undergraduates students as users. The study was conducted from October to November 2019, in Bogor, West Java. The design of this study was a cross-sectional study with the withdrawal of subjects using a purposive method and the total number of subjects are 105. The results showed that price was scored as the most important food choice motive (mean = 3.60; median = 4.0). This study found the association between practices and motives associated with pocket money and sex. Price and religion significantly correlated with food choice practices (p = 0.050 dan p = 0.019).
Keyword: application, motives, online food delivery, practice

Judul: Motivasi dan Praktik Pemilihan Pangan Melalui Aplikasi Pemesanan Pangan Daring pada Pegawai Kota Bogor
Abstrak: Inovasi teknologi menunjang berbagai macam aktifitas kehidupan menjadi lebih praktis, salah satunya penyediaan pangan melalui aplikasi pemesanan pangan daring yang dapat mempengaruhi kebiasaan konsumsi pangan. Penelitian ini bertujuan menggambarkan motivasi dan praktik pemilihan pangan melalui aplikasi pemesanan pangan daring pada pegawai. Penelitian dilakukan bulan November sampai Desember 2019 di Bogor. Desain studi berupa cross sectional study dengan penarikan 105 orang subjek menggunakan metode convenience sampling, yaitu yang ditemui dan dipilih berdasarkan kesediaan menjadi subjek sesuai dengan kriteria inklusi penelitian. Pengumpulan data dilakukan dengan pengisian kuesioner. Hasil penelitian menunjukkan bahwa mayoritas subjek merupakan perempuan berusia 25-35 tahun, status menikah dan bekerja sebagai pegawai swasta. Agama merupakan motivasi yang paling dipertimbangkan oleh subjek (mean= 3,77). Praktik pemilihan pangan yang dilakukan mayoritas pada kelompok pangan fast food lokal (3,04 kali/bulan). Karakteristik subjek, usia (p= 0,012), jenis kelamin (p= 0,008; p= 0,039; p= 0,024; p= 0,033) dan status pernikahan (p= 0,048) berhubungan signifikan dengan motivasi pemilihan pangan. Usia berhubungan signifikan dengan praktik pemilihan minuman (p= 0,001). Motivasi suasana hati berhubungan signifikan dengan praktik pemilihan minuman (p= 0,044)., The innovation of technology has supporting various activities more practical, one of them is provision food through online food delivery apps that affect food consumption habits. This study aimed to analyze food choice motives and practices through online food delivery (OFD) apps on Bogor employees. The study was conducted from November to December 2019 in Bogor. The design of this study was a cross-sectional study with 105 subjects drawn using covenience sampling based on their availability and willingness to. Data was collected by self-administered questionnaire. The result showed most of subject are female aged 25-35 years old, married and worked as private employees. Religion was scored as the most important food choice motive (mean = 3.77). The local fast food is the most food choice practice (3.04 times/month). Subject characteristics, such as age (p=0.012), gender (p=0.008; p=0.039; p=0.024; p=0.033) and marital status (p=0.048), were significantly correlated with food choice motives. Age significantly correlated with beverage choice practice (p=0.001). Mood motives significantly correlated with beverage choice practice (p=0.044).
Keyword: application, motives, online, practice

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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