Judul: The Influence of BTS as a Brand Ambassador on Brand Image and Purchase Intention of Comsumers Tokopedia in Indonesia
Abstrak: Mewabahnya virus corona menyebabkan terjadinya perubahan yang cukup signifikan, salah satunya kegiatan belanja. Mengawali tahun 2021, Tokopedia menggandeng boysgroup Korea, Bangtan Sonyeondan (BTS) sebagai brand ambassadornya. Tokopedia merupakan perusahaan e-commerce yang terus melakukan pengembangan strategi marketing untuk mendongkrak loyalitas dan minat beli konsumennya. Tujuan dilakukan penelitian ini ialah untuk mengidentifikasi karakteristik konsumen pengguna platform Tokopedia, menganalisis pengaruh brand ambassador terhadap brand image, menganalisis pengaruh brand ambassador terhadap minat beli konsumen, serta menganalisis pengaruh brand image terhadap minat beli konsumen. Metode analisis data yang digunakan adalah analisis deskriptif dan analisis SEM-PLS. Hasil penelitian menunjukkan bahwa terdapat pengaruh antara variabel brand ambassador terhadap brand image serta variabel brand image terhadap minat beli konsumen, sedangkan antara variabel brand ambassador terhadap minat beli konsumen tidak memiliki pengaruh., The outbreak of the corona virus has caused significant changes, one of which is shopping activities. Starting 2021, Tokopedia collaborates with the Korean boy group, BTS as its brand ambassador. Tokopedia is an e-commerce company that continues to develop marketing strategies to boost consumer loyalty and buying interest. The purpose of this research is to identify consumer characteristics of users of the Tokopedia platform, analyze the influence of brand ambassadors on brand image, analyze the influence of brand ambassadors on consumer purchase intention, and analyze the influence of brand image on consumer purchase intention. The data analysis method used is descriptive analysis and SEM-PLS analysis. The results showed that there was an influence between brand ambassador variables on brand image and brand image variables on consumer purchase intention, while between brand ambassador variables on consumer purchase intention had no effect.
Keyword: Brand ambassador, Brand image, BTS, Purchase intention, Tokopedia

Judul: Analisis Persepsi Konsumen terhadap Keputusan Pembelian Online di Tokopedia.
Abstrak: Pengguna internet di Indonesia semakin meningkat. Hal itu berpengaruh positif terhadap transaksi jual beli online. Pada saat ini persaingan e-commerce semakin ketat di Indonesia. Tokopedia harus meningkatkan keunggulan dalam bersaing dengan e-commerce lainnya untuk menarik banyak konsumen dengan memahami persepsi konsumen dalam pengambilan keputusan pembelian. Tujuan dari penelitian ini adalah mengidentifikasi karakteristik konsumen Tokopedia dan menganalisis pengaruh harga, kualitas layanan, dan merek terhadap keputusan pembelian online Tokopedia. Metode pemilihan sampel menggunakan metode non-probability sampling dengan teknik purposive sampling. Metode analisis yang digunakan adalah analisis regresi linier berganda. Hasil uji F menunjukkan bahwa pengaruh harga, kualitas layanan dan citra merek berpengaruh signifikan terhadap keputusan pembelian online tokopedia (sig. 0.000). Hasil uji t bahwa harga (sig. 0.044), kualitas layanan (sig. 0.040), dan citra merek (sig. 0.000) memiliki pengaruh signifikan terhadap keputusan pembelian online Tokopedia.
Keyword: keputusan pembelian, regresi linier berganda, Tokopedia

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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