Judul: Pengaruh E-Service Quality Terhadap Purchase Intention dan Purchase Decision di Shopee Pada Masa Pandemi COVID-19
Abstrak: Perkembangan teknologi informasi sangat pesat dengan adanya internet membuat gaya hidup belanja seseorang berubah. Kondisi pandemi COVID-19 membuat seseorang mengutamakan belanja online karena adanya dampak pembatasan sosial dan fisik. Ditengah persaingan yang ketat diantara e-commerce membuat Shopee harus meningkatkan keunggulan dalam bersaing untuk menarik konsumen. Penelitian ini bertujuan untuk menganalisis pengaruh e-service quality dalam purchase intention dan purchase decision. Metode penarikan sampel yang digunakan adalah non-probability sampling dengan teknik purposive sampling dengan jumlah sampel sebanyak 400 responden. Analisis yang digunakan adalah analisis deskriptif dan stuctural equation model-partial least square. Hasil dari penelitian ini menunjukkan bahwa variabel security/privacy dan variabel website design berpengaruh secara signifikan dan positif terhadap variabel purchase intention dan purchase decision. Sedangkan variabel compensation, fulfillment, dan responsiveness tidak berpengaruh terhadap keduanya. Purchase intention berpengaruh secara signifikan dan positif terhadap purchase decision.
Keyword: e-commerce, e-service quality, purchase decision, purchase intention

Judul: The Effect of Online Consumer Review and Rating  on Purchase Intention of Health Products on Shopee E-Marketplace During the  Covid-19 Pandemic in Jabodetabek
Abstrak: Pandemi COVID-19 menyebabkan peningkatan pembelian produk-produk kesehatan seperti masker, handsanitizer, obat-obatan dan lain-lain. Shopee merupakan salah satu e-marketplace yang sedang berkembang di Indonesia dan menyediakan fitur online consumer review dan rating pada platformnya. Penelitian ini bertujuan untuk menganalisis pengaruh online consumer review dan rating terhadap minat beli produk kesehatan pada e-marketplace Shopee selama masa pandemi COVID-19 di Jabodetabek. Penarikan sampel dilakukan dengan teknik purposive sampling. Metode yang digunakan dalam penelitian ini adalah analisis deskriptif dan SEM-PLS. Hasil analisis menunjukkan variabel online consumer review dan rating berpengaruh positif dan signifikan terhadap minat beli produk kesehatan dengan variabel rating memiliki pengaruh lebih dominan., COVID-19 pandemic led to an increase in purchases of health products such as masks, handsanitizers, medicines and others. Shopee is one of the growing online marketplaces in Indonesia that provides online consumer review and rating features on its. This study aimed to analyze the effect of online consumer review and rating on purchase intention of health products on shopee online marketplace during the COVID-19 pandemic. The sampling method used in this study was purposive sampling technique. The method used in this research was descriptive analysis and SEM-PLS. The results of the analysis show that online consumer review and rating variables have a positive and significant effect on purchase intention in health products with the rating variable as the dominant influence.
Keyword: Health Products, Online Consumer Review, Purchase Intention, Rating, Shopee

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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