Judul: Analysis of Unreported Fisheries Data in Labuan Landing Port, Banten
Abstrak: Pengelolaan kegiatan perikanan di perairan Selat Sunda didukung oleh PPP Labuan, Banten. Pengelolaan yang baik akan mencegah ketidakpastian data perikanan yang digunakan sebagai acuan dalam pengkajian status ikan. Penelitian bertujuan menganalisis data perikanan yang tidak dilaporkan di PPP Labuan, Banten. Penelitian dilaksanakan pada bulan September 2022 sampai Maret 2023 di PPP Labuan. Pengumpulan data dilakukan melalui pengisian kuesioner, observasi langsung, dan data produksi TPI. Pencatatan di PPP Labuan dilaksanakan saat kegiatan pelelangan di TPI. Persentase kehilangan data terbesar diurutkan dari kelompok Apollo (92,09%), Rawai/Rampus/Apollo Campuran (RRAC) (16,09%), dan Payang/Purse seine (PPS) (14,15%), sedangkan berat produksi terbesar yang tidak dilaporkan diurutkan dari PPS (32-415 kg/trip), RRAC (10-172 kg/trip), dan Apollo (17-86 kg/trip). Kehilangan data kelompok Apollo didominansi dari penjualan ke pasar, sedangkan kelompok RRAC dan PPS dari jatah ABK. Faktor penyebab terbanyak terjadi karena nelayan belum bersedia mengisi log book (84 kapal) dan kekurangan pengawasan (73 kapal). Secara keseluruhan, data yang tidak dilaporkan diestimasi mencapai 18,24% dari ketiga kelompok alat tangkap., The management of fisheries activities in the waters of the Sunda Strait is supported by PPP Labuan, Banten. Good management will prevent uncertainty in fisheries data, which is used as a reference in assessing the fish stocks’ status. The research aims to analyze the unreported fishery data in PPP Labuan, Banten. The research was conducted from September 2022 to March 2023 in PPP Labuan. Data collection was carried out through questionnaires, direct observation, and production data. The data collection system at PPP Labuan is implemented during auction at port. The highest percentage of data loss is ranked among the Apollo (92.09%), Rawai/Rampus/mixed Apollo (RRAC) (16.09%), and Payang/Purse seine (PPS) (14.15%). In terms of production weight, the largest losses are found in the PPS (32-415 kg/trip), RRAC (10-172 kg/trip), and Apollo (17-86 kg/trip). Data loss in the Apollo group is predominantly due to sales to the market, while the RRAC and PPS are affected by crew allocation as payment. The main contributing factors are fishermen's unwillingness to fill log book (84 vessels) and lack of supervision (73 vessels). Unreported data is estimated to 18.24% across all groups.
Keyword: Data loss, data uncertainty, Labuan

Judul: Accuracy of Catch Data at Tegalsari Fishing Port, Central Java
Abstrak: Pelabuhan Perikanan Pantai (PPP) Tegalsari memiliki aktivitas bongkar muat ikan yang aktif di Jawa Tengah. Salah satu permasalahan yang muncul adalah perbedaan data produksi hasil tangkapan. Perbedaan ini mengakibatkan ketidakakuratan data hasil tangkapan. Penelitian ini bertujuan menghitung tingkat keakuratan, menganalisis faktor krusial penyebab ketidakakuratan, dan merumuskan strategi peningkatan keakuratan data produksi hasil tangkapan Jaring tarik berkantong (JTB) di PPP Tegalsari. Metode yang digunakan yaitu observasi lapangan dan kuesioner. Metode analisis yang digunakan yaitu keakuratan data, fishbone, dan SWOT. Hasil penelitian menunjukkan bahwa dari tiga puluh kali proses pendataan, sebanyak 24 pendataan (80%) memiliki tingkat keakuratan data (TKD) > 95%. Sedangkan, sebanyak 6 pendataan (20%) memiliki TKD < 95%. Hasil analisis fishbone menunjukkan faktor krusial penyebab ketidakakuratan diantaranya pembulatan angka pada timbangan yang tidak sesuai, timbangan yang tidak dikalibrasi, pemilihan material pendataan yang tidak tepat, beban kerja enumerator yang berlebih, dan cuaca yang berubah-ubah. Hasil analisis matriks SWOT menunjukkan adanya delapan alternatif strategi peningkatan keakuratan data, dengan strategi utama yaitu penyesuaian pembulatan angka pada proses pendataan hasil tangkapan sesuai dengan aturan yang berlaku., Tegalsari Coastal Fishing Port (PPP) has active loading and unloading fish activities in Central Java. One of the problems that arise is the difference in catch production data. This difference can result in inaccurate catch data. This study aims to calculate the level of accuracy, analyze the crucial factors causing inaccuracies, and formulate strategies to improve the accuracy of catch production data of seine net (JTB) at PPP Tegalsari. The methods used were field observation and questionnaires. The analysis methods used are data accuracy, fishbone, and SWOT. The results showed that out of thirty data collection processes, 24 data collections (80%) had a data accuracy rate (TKD) > 95%. Meanwhile, 6 data collections (20%) had TKD < 95%. The results of the fishbone analysis indicate several crucial factors contributing to inaccuracy, including improper abbreviation of numbers on scales, uncalibrated scales, incorrect choice of data collection materials, excessive workload of enumerators, and changing weather conditions. The results of the SWOT matrix analysis showed eight alternative strategies for improving data accuracy, with the main strategy being to adjust the rounds the numbers in the catch data collection process in accordance with applicable regulations.
Keyword: data hasil tangkapan, keakuratan data, pelabuhan perikanan pantai tegalsari, penyimpangan data

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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