Judul: Kelayakan Usaha Perikanan Cast net di Pelabuhan Perikanan Nizam Zachman Jakarta.
Abstrak: Armada kapal cast net terus bertambah di PPS Nizam Zachman Jakarta (PPSNZJ) karena banyak pengusaha cumi-cumi pemula yang baru terjun bisnis perikanan cumi-cumi dan menjadi salah satu faktor bertambahnya armada disana. Sehingga menyebabkan tingginya kompetisi saing antar pengusaha. Penelitian ini bertujuan mengevaluasi produktivitas dan kelayakan usaha cast net di PPSNZJ guna meberikan informasi untuk perencaan bisnis yang dapat digunakan oleh seseorang yang akan mencoba bisnis sektor perikanan cumi-cumi. Dilakukan melalui metode accidental sampling dengan teknik wawancara. Data dianalisis secara deskriptif kualitatif untuk hasil kelayakan usaha non-finansial dan dianalisis secara kuantitatif untuk produktivitas dan kelayakan usaha finansial. Sampel meliputi kapal cast net berukuran 20-30 GT, 31-50 GT, dan 51-100 GT. Hasilnya kelayakan usaha perikanan cast net menunjukkan bahwa kapal dengan ukuran 31-50 GT dan 51-100 GT termasuk kategori finansial layak usaha, sedangkan untuk ukuran 20-30 GT termasuk kategori finansial tidak layak usaha., The fleet of cast net vessels continues to grow at PPS Nizam Zachman Jakarta (PPSNZJ) because there are many new squid entrepreneurs who have just entered the squid fisheries business and are one of the factors for the increase in the fleet there. This has led to high competition among entrepreneurs. This study aims to evaluate the productivity and feasibility of the cast net business at PPSNZJ in order to provide information for business planning that can be used by someone who will try the squid fishery sector business. Conducted through accidental sampling method with interview technique. Data were analyzed descriptively qualitatively for non-financial business feasibility results and quantitatively analyzed for productivity and financial business feasibility. Samples included cast net vessels of 20-30 GT, 31-50 GT, and 51-100 GT. The results of cast net fishery business feasibility showed that vessels of 31-50 GT and 51-100 GT were categorized as financially viable, while those of 20-30 GT were categorized as financially unviable.
Keyword: business feasibility, cast net, Nizam Zachman Ocean Fishing Port Jakarta, productivity, squid

Judul: Fishermen's Income Level on Cast net Fishing Gear at the Kejawanan Fishing Port
Abstrak: Sumberdaya perikanan yang tinggi dapat dimanfaatkan untuk meningkatkan perekonomian nelayan, namun kenyataanya penghasilan nelayan masih tergolong rendah. Faktor penyebab rendahnya penghasilan yaitu kurangnya modal dan sistem penghasilan yang diterapkan oleh nelayan dengan pemilik kapal. Tujuan penelitian ini mengetahui sistem penghasilan dan menganalisis tingkat penghasilan nelayan cast net di Pelabuhan Perikanan Nusantara Kejawanan. Metode yang digunakan yaitu survei dan melakukan wawancara. Kapal cast net di PPN Kejawanan menerapkan sistem penghasilan bagi hasil dan sistem gaji nelayan. Mekanisme sistem bagi hasil terdapat potongan atas sebesar 27% dari hasil penjualan dan dikurangi biaya operasional, hasil sisa potongan atas yaitu potongan bawah yang akan dibagi 50% untuk pemilik dan 50% untuk awak kapal, sedangkan sistem gaji dengan rata-rata upah harian nelayan cast net untuk KKM sebesar Rp72.273,00, ABK sebesar Rp33.128,00, dan nahkoda sebesar 13% dengan nilai Rp103.231.818,00 dari hasil penjualan kotor dalam satu trip. Tingkat penghasilan perbulan nelayan cast net pada sistem bagi hasil dan sistem gaji untuk nahkoda dan KKM berada diatas UMK, sedangkan untuk ABK masih berada dibawah UMK Kota Cirebon., High fishery resources can be utilized to improve the economy of fishermen, but in reality, the income of fishermen is still relatively low. Factors causing low income are lack of capital and income system applied by fishermen with ship owners. The purpose of this study was to determine the income system and analyze the income level of cast net fishermen in Kejawanan Nusantara Fishing Port. The method used was survey and interview. Cast net vessels in Kejawanan fishing port apply a profit-sharing income system and a fisherman salary system. The mechanism of the profit sharing system has an upper cut of 27% of the sales proceeds and deducts operational costs, the remaining results of the upper cut are the lower cut which will be divided 50% for the owner and 50% for the crew, while the salary system with an average daily wage for cast net fishermen for KKM is IDR 72.273,00, crew is IDR 33.128,00, and the captain is 13% with a value of IDR 103.231.818.00 from the gross sales in one trip. The level of monthly income of cast net fishermen in the profit sharing system and salary system for the captain and KKM is above the minimum wage, meanwhile for the crew is still below the minimum wage of Cirebon City.
Keyword: jala jatuh berkapal, nelayan, penghasilan, PPN Kejawanan

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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