Judul: The Impact of Covid-19 Pandemic on Fish Marketing Activities at Palabuhanratu Fish Auction
Abstrak: Pandemi covid-19 menyebabkan terbatasnya kegiatan di tengah masyarakat dan hal tersebut diduga akan berdampak pada kegiatan pemasaran di Tempat Pelelangan Ikan (TPI) Palabuhanratu. Tujuan penelitian ini adalah mengidentifikasi dampak covid-19 terhadap aktivitas pemasaran ikan di TPI Palabuhanratu, membandingkan keuntungan pedagang ikan pada saat sebelum covid-19 dengan saat pandemi covid-19 dan merekomendasikan strategi untuk mengatasi dampak covid-19 terhadap aktivitas pemasaran ikan di TPI Palabuhanratu. Penelitian ini menggunakan metode studi kasus. Teknik pengambilan data untuk tujuan pertama dan kedua menggunakan metode accidental sampling serta tujuan ketiga menggunakan metode purposive sampling. Analisis data terdiri dari analisis deskriptif metode skoring, analisis keuntungan usaha, dan matriks SWOT. Hasil penelitian menunjukkan bahwa berdasarkan persepsi responden, terjadi beberapa perubahan aktivitas pemasaran ikan pada saat pandemi seperti menurunnya jumlah konsumen, harga jual ikan menurun, pendapatan pedagang menurun, serta menurunnya jumlah ikan yang dijual. Keuntungan pedagang mengalami penurunan hingga 50% yang berpengaruh terhadap biaya usaha dan total penerimaan para pedagang. Strategi dalam mengatasi dampak pandemi covid-19 terhadap aktivitas pemasaran ikan di TPI Palabuhanratu ialah penguatan sistem lelang, peningkatan fasilitas pendistribusian hasil tangkapan ke industri maupun pasar diluar daerah TPI, menyediakan layanan internet dan sosisalisasi digital marketing kepada para pedagang, menambah cold storage, dan melakukan sistem resi gudang ikan., Covid-19 pandemic caused limited activities in public and it is expected to have an impact on marketing activities at the Palabuhanratu Fish Auction (TPI). The purpose of this research are to identify the impact of covid-19 on fish marketing activities at TPI Palabuhanratu, compare the profits of fish traders in the time before covid-19 with during the covid-19 pandemic and recommend strategies to overcome the impact of covid-19 on fish marketing activities in TPI Palabuhanratu. This research use case study methods. Data collection techniques for the first and second purpose use accidental sampling methods as well as for the third-purpose using purposive sampling methods. Data analysis consists of descriptive analysis of scoring methods, profit analysis, and SWOT matrix. Result showed that based on respondents perception there were several changes in fish marketing activities during the pandemic such as declining consumer numbers, declining fish selling prices, declining merchant income, and decreasing the number of fish sold. Traders profits decreased by up to 50% which affects business costs and total acceptance of traders. Strategies in overcoming the impact of the covid-19 pandemic on fish marketing activities in TPI Palabuhanratu are strengthening the auction system, improving the distribution of catch facilities to industries and markets outside the TPI area, providing internet services and digital marketing socialization to traders, adding cold storage, and conducting fish warehouse receipt systems.
Keyword: Covid-19, Ikan, Palabuhanratu, Pedagang, Pemasaran

Judul: Dynamics of Fish Landings at the Archipelago Fishing Port of Palabuhanratu
Abstrak: Pelabuhan perikanan memiliki fungsi penting sebagai pengembangan dalam bidang ekonomi. Namun pada tahun 2020 terjadi fenomena pandemi Covid–19 yang mengakibatkan penurunan pada beberapa faktor yang menentukan kepadatan aktivitas pendaratan ikan di PPN Palabuhanratu. Tujuan penelitian adalah mengetahui kondisi pendaratan ikan, menganalisis konsentrasi aktivitas pendaratan ikan, dan mengetahui distribusi pendapatan nelayan pada kondisi terkini di PPN Palabuhanratu. Subjek dalam penelitian ini adalah pemilik kapal atau nelayan kapal dan pengelola Pelabuhan. Teknik pengambilan data menggunakan metode stratified random sampling. Hasil penelitian menunjukkan bahwa terdapat 6 faktor yang menentukan aktivitas pendaratan ikan di PPN Palabuhanratu, nilai konsentrasi aktivitas pendaratan ikan di PPN Palabuhanratu menunjukkan bahwa nilai frekuensi kapal masuk yang mendaratkan ikan hasil tangkapan dikategorikan sebagai konsentrasi pasar moderat, dan distribusi pendapatan nelayan di PPN Palabuhanratu kedalam kategori dengan nilai ukuran ketimpangan tinggi yaitu sebesar 4% dengan nilai gini rasio sebesar 0,69., The fishing port serves a crucial role in economic development. However, in 2020, the covid-19 pandemic resulted in a decline in several factors determining the density of fish landing activities at PPN Palabuhanratu. The research aims to understand the condition of fish landing, analyze the concentration of fish landing activities, and understand the distribution of fishermen’s income in the current conditions at PPN Palabuhanratu. The subjects of this research are ship owners or fishermen and port management. Data collection was carried out using stratified random sampling, the concentration value of fish landing activities at PPN Palabuhanratu shows that the frequency of incoming vessels landing caught fish is categorized as moderate market concentration, and the distribution of fishermen’s income is categorized as having a high level of inequality, which is 4% with the gini ratio of 0,69.
Keyword: income distribution, density, concentration, landing, PPN Palabuhanratu

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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