Judul: Efektivitas Media Sosial Sebagai Media Promosi Taman Hutan Raya IR. H. Djuanda di Masa Pandemi Covid-19
Abstrak: Pandemi Covid-19 mengakibatkan adanya pemberlakuan PSBB dan menimbulkan menurunnya kegiatan berwisata. Penelitian bertujuan menganalisis efektivitas media sosial sebagai media promosi dan melihat hubungannya dengan karakteristik konsumen, karakteristik media sosial, dan kredibilitas media sosial, serta hubungan antara efektivitas media sosial dengan keputusan berkunjung di masa pandemi Covid-19. Metode yang digunakan yaitu metode kuantitatif menggunakan kuesioner untuk 50 responden dengan teknik accidental sampling. Hasil penelitian menunjukkan bahwa efektivitas media sosial selama pandemi Covid-19 sudah cukup bagus dan memiliki hubungan dengan keputusan berkunjung wisatawan. Selain itu, karakteristik konsumen tidak memiliki hubungan dengan efektivitas media sosial sebagai media promosi selama pandemi Covid-19 sementara Karakteristik media sosial dan kredibilitas media sosial memiliki hubungan dengan efektivitas media sosial sebagai media promosi selama pandemi Covid-19., The Covid-19 pandemic has resulted in the implementation of PSBB and has led to a decrease in tourist activities. The study aims to analyze the effectiveness of social media as a promotional media and its relationship with consumer characteristics, social media characteristics, and social media credibility, as well as the relationship between the effectiveness of social media and the decision to visit Djuanda Forest Park during the Covid-19 pandemic. The method used is a quantitative method using a questionnaire for 50 respondents with an accidental sampling technique. The results showed that the effectiveness of social media Djuanda Forest Park during the Covid-19 pandemic was good and had a relationship with the decision of tourists to visit Djuanda Forest Park. In addition, consumer characteristics do not have a relationship with the effectiveness of social media while social media characteristics and social media credibility have a relationship with the effectiveness of social media as a promotional media Djuanda Forest Park during the Covid-19 pandemic.
Keyword: covid-19, consumer characteristics, social media characteristics, social media credibility, visit decision

Judul: The Effectiveness of E-WOM through Instagram as Viral Marketing Media for Agroedutourism during the COVID-19 Pandemic
Abstrak: Pembatasan Kegiatan Masyarakat (PPKM) selama masa pandemi COVID-19 membuat sektor pariwisata terdampak. Destinasi wisata Kota Bogor, yaitu Kampung Agroeduwisata Organik Mulyaharja harus tutup sementara dan melakukan promosi melalui media sosial pasca-PPKM. Salah satu strategi promosi yang efektif dilakukan di media sosial adalah electronic word of mouth dimana calon pengunjung dapat mendapat rekomendasi dan informasi berdasar pengalam pribadi yang membantu memutuskan kunjungan. Tujuan dari penelitian ini adalah untuk menganalisis efektivitas e-WOM dan media sosial Instagram sebagai media pemasaran viral Kampung wisata di masa pandemi COVID-19. Metode yang digunakan adalah metode kuantitatif dengan kuesioner online dan didukung dengan data kualitatif melalui wawancara mendalam. Responden pada penelitian ini adalah followers Instagram @visitmulyaharja berjumlah 44 orang yang didapatkan melalui teknik accidental sampling. Hasil penelitian menunjukkan bahwa penilaian responden terhadap dimensi electronic word of mouth yang paling kuat adalah valensi pendapat, efektivitas strategi promosi di masa pandemi ternyata efektif untuk meningkatkan perhatian dan ketertarikan followers, dan terdapat faktor-faktor yang berhubungan dengan efektivitas strategi promosi, yaitu dimensi intensitas berhubungan kuat dengan share, konten berhubungan kuat dengan search, dan valensi pendapat berhubungan kuat dengan interest, Restrictions on Community Activities (PPKM) during the COVID-19 pandemic impacted the tourism sector. The Bogor City tourist destination, namely the Mulyaharja Organic Agroedutourism Village, must temporarily close and promote through post-PPKM social media. One of the effective promotional strategies carried out on social media is electronic word of mouth where potential visitors can get recommendations and information based on personal experiences that help decide on a visit. The purpose of this study was to analyze the effectiveness of e-WOM and Instagram social media as viral marketing media for Kampung Wisata during the COVID-19 pandemic. The method used is a quantitative method with an online questionnaire and is supported by qualitative data through in-depth interviews. Respondents in this study were Instagram followers @visitmulyaharja totaling 44 people obtained through accidental sampling technique. The results showed that the respondents' assessment of the strongest electronic word of mouth dimension was opinion valence, the effectiveness of promotional strategies during the pandemic was effective in increasing followers' attention and interest, and there were factors related to the effectiveness of promotional strategies, namely the intensity dimension associated Strongly related to share, content was strongly related to search, and opinion valence was strongly related to interest.
Keyword: agroeduwisata, e-WOM, Instagram, pandemi

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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