Judul: Pengaruh Rating dan Online Customer Review Terhadap Keputusan Pembelian di E-commerce Shopee
Abstrak: Kemajuan teknologi informasi menimbulkan adanya E-commerce yang membuat aktivitas belanja menjadi semakin mudah. Berdasarkan jumlah pengunjung bulanan situs E-commerce pada kuartal IV 2020, Shopee merupakan E-commerce yang paling banyak dikunjungi oleh pengguna internet. Penelitian ini bertujuan menganalisis pengaruh rating dan online customer review terhadap keputusan pembelian di E-commerce Shopee. Sumber data menggunakan data primer yang diperoleh berdasarkan hasil pengisian kuesioner oleh responden dan data sekunder yang diperoleh melalui literasi jurnal ilmiah, buku, dan sumber bacaan lainnya. Penelitian ini dilaksanakan pada bulan juni 2022. Responden pada penelitian ini adalah mahasiswa Institut Pertanian Bogor. Teknik data yang digunakan yaitu uji validitas dan uji reliabilitas dengan metode pengolahan data yang digunakan yaitu analisis deskriptif dan SEM-PLS. Hasil penelitian menjelaskan bahwa Variabel rating berpengaruh secara positif dan signifikan terhadap variabel keputusan pembelian dan variabel customer online review berpengaruh secara positif dan signifikan terhadap keputusan pembelian., Advances in information technology have given rise to E-commerce which makes shopping activities easier. Based on the number of monthly visitors to E-commerce sites in the fourth quarter of 2020, Shopee is the most visited E-commerce by internet users. This study aims to analyze the effect of ratings and online customer reviews on purchasing decisions at E-commerce Shopee. Data sources use primary data obtained based on the results of filling out questionnaires by respondents and secondary data obtained through literacy in scientific journals, books and other reading sources. This research was conducted in June 2022. Respondents in this study were students of the Bogor Agricultural University. The data technique used is the validity test and reliability test with the data processing method used is descriptive analysis and SEM-PLS. The results of the study explain that the rating variable has a positive and significant effect on the purchasing decision variable and the online customer review variable has a positive and significant effect on the purchasing decision. Keywords: E-commerce, Online Customer Review, Rating, Purchase Decision, SEM-PLS
Keyword: E-commerce, Online Customer Review, Rating, Purchase Decision, SEM-Pls

Judul: Pengaruh Online Consumer Review dan Rating  terhadap Purchase Intention Produk Serum Somethinc pada Marketplace Shopee di Jabodetabek
Abstrak: Peningkatan jumlah pengguna internet menciptakan banyak peluang bagi para pengusaha, sehingga mengakibatkan peningkatan jumlah e-commerce dan marketplace di Indonesia. Shopee adalah salah satu marketplace Indonesia yang menawarkan fitur online consumer review dan rating di platform. Tujuan penelitian ini menganalisis pengaruh online consumer review dan rating terhadap purchase intention produk serum Somethinc pada marketplace Shopee. Jenis penelitian ini adalah penelitian kuantitatif dengan teknik pengambilan sampel purposive sampling. Data penelitian dikumpulkan pada bulan April – Mei 2023 melalui kuesioner dari 150 responden di Jabodetabek sebagai data primer dan melalui studi literatur dari buku, jurnal, dan artikel terkait sebagai data sekunder. Penelitian ini menggunakan metode analisis deskriptif dan Structural Equation Modeling-Partial Least Square (SEM-PLS). Hasil penelitian menunjukkan variabel online consumer review dan rating berpengaruh signifikan dan positif terhadap purchase intention produk serum Somethinc dengan variabel rating memiliki pengaruh lebih dominan., The increase in the number of internet users creates many opportunities for entrepreneurs, resulting in an increase in the number of e-commerce sites and marketplaces in Indonesia. Shopee is one of the Indonesian marketplaces that offers online consumer review and rating features on its platform. The purpose of this study was to analyze the effect of online consumer review and rating on purchase intention of Somethinc serum products on Shopee marketplace. This type of research is quantitative research with purposive sampling technique. The research data was collected in April - May 2023 through questionnaires from 150 respondents in Jabodetabek as primary data and through literature studies from books, journals, and related articles as secondary data. This research uses the descriptive analysis method and Structural Equation Modeling-Partial Least Square (SEM-PLS). The results showed that the online consumer review and rating variables had a significant and positive effect on the purchase intention of Somethinc serum products with the rating variable having a more dominant influence.
Keyword: online consumer review, purchase intention, rating, Shopee, Somethinc  serum

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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