Judul: Supply Chain Analysis on Spiny Lobster Panulirus homarus in WPP 712
Abstrak: Peraturan Menteri Kelautan dan Perikanan (PERMEN) Nomor 17 Tahun 2021 melarang distribusi Benih Bening Lobster (BBL) diluar lokasi penangkapan dan menetapkan ukuran minimal lobster ekspor dengan bobot melebihi 150 g. Peraturan ini berdampak pada proses produksi dan distribusi lobster, sehingga perlu diketahui model rantai pasok lobster. Penelitian ini bertujuan menganalisis proses, jejaring, pelaku, efisiensi dan peluang risiko yang terdapat pada rantai pasok lobster. Data primer diperoleh dari wawancara dengan metode snowball. Analisis data menggunakan margin pemasaran, farmer’s share, dan metode failure mode and effect analysis (FMEA). Hasil penelitian didapatkan proses produksi lobster belum sesuai dengan segmentasi PERMEN KP Nomor 17 Tahun 2021. Aliran rantai yang mengalir pada rantai pasok yaitu aliran informasi yang mengalir ke dua arah, aliran barang yang mengalir dari hulu ke hilir, dan aliran harga yang mengalir dari hilir ke hulu. Pelaku rantai pasok lobster yaitu nelayan, pengepul, pembudidaya, pedagang grosir, pengecer, eksportir, restoran, importir, dan konsumen akhir. Rantai pasok lobster yang mengalir dari pembudidaya menuju restoran lebih efisien dari saluran pembudidaya menuju eksportir. Ketersediaan benih yang belum berkelanjutan merupakan peluang risiko yang memberikan dampak tertinggi berdasarkan analisis FMEA., Minister of Marine Affairs and Fisheries Regulation (PERMEN KP) Number 17 of 2021 prohibits the distribution of Lobster Bening Seed (BBL) outside the fishing grounds and stipulates a minimum size of export lobster with a weight exceeding 150 g. This regulation has an impact on the lobster production and distribution process, so it is necessary to know the lobster supply chain model. This study aims to analyze the process, network, actors, efficiency, and risk opportunities contained in the lobster supply chain. Primary data were obtained from interviews with the snowball method. Data analysis used marketing margin, farmer's share, and failure mode and effect analysis (FMEA) method. The results showed that the lobster production process was not following the segmentation of PERMEN KP Number 17 of 2021. The chain flow that flows in the supply chain is the flow of information that flows in two directions, the flow of goods that flow from upstream to downstream, and the flow of prices that flows from downstream to upstream. The actors in the lobster supply chain are fishermen, collectors, cultivators, wholesalers, retailers, exporters, restaurants, importers, and final consumers. The lobster supply chain that flows from farmers to restaurants is more efficient than the channel from farmers to exporters. The availability of unsustainable seeds is a risk opportunity that has the highest impact based on the FMEA analysis.
Keyword: Aquaculture, lobster, marketing margin, supply chain

Judul: Fisher Perceptions of Lobster Seed Exports and Their  Effect on the Sustainability of Lobster Fisheries in Palabuhanratu
Abstrak: Menteri Kelautan dan Perikanan pada tahun 2020, melalui penetapan PERMEN KP No.12/2020 memperbolehkan ekspor benih lobster. Pemerintah pada tahun 2021 kembali mengeluarkan kebijakan pelarangan ekspor benih lobster yang bertujuan untuk menjaga sumberdaya lobster tercantum dalam PERMEN KP No.17/2021. Kemudian tahun 2022 beberapa isi kebijakan kembali direvisi melalui PERMEN KP No.16/2022. Adanya perubahan kebijakan pemerintah dapat memicu terjadinya konflik. Hal ini terbukti dengan masih banyaknya kasus penyelundupan benih lobster yang terjadi. Penelitian ini bertujuan mendeskripsikan kebijakan pemerintah terkait dengan ekspor lobster, mengidentifikasi persepsi nelayan terhadap kebijakan ekspor lobster, mengkaji dampak kebijakan ekspor lobster terhadap keuntungan usaha nelayan dan keberlanjutan perikanan lobster. Penelitian menggunakan metode studi kasus dengan proses pengumpulan data meliputi wawancara, observasi langsung, dan data sekunder. Analisis deskriptif dan keuntungan digunakan dalam menganalisis data yang didapatkan. Hasil penelitian menunjukkan persepsi nelayan Palabuhanratu, terhadap penerapan kebijakan PERMEN KP No.17/2021 sebanyak (38%) menunjukkan persepsi yang negatif, dan sisanya sebanyak 58% bersikap netral, serta 4% setuju. Ketidakpastian mengenai harga jual benih lobster yang dipasok ke pengepul, berdampak pada besar kecilnya nilai pendapatan nelayan. Hal yang dapat dilakukan untuk menjamin keberlanjutan perikanan lobster di Palabuhanratu yaitu dengan mengoptimalkan pembudidayaan benur lobster sampai ukuran dewasa untuk menampung hasil tangkapan benur lobster dari nelayan yang melimpah., The Minister of Maritime Affairs and Fisheries in 2020, through PERMEN KP No. 12/2020 explained the policies and regulation of export lobster juvenile. In 2021, the government made another policies and explained banned regulation of lobster juvenile export. This policies was aims to protect lobster resources as stated in PERMEN KP No. 17/2021. Then in 2022 some of the policy contents were revised again through PERMEN KP No.16/2022. By the changes of government policies and regulations, can cause many conflicts. One of the conflicts that causes by the changes of government policies was lobster seed smuggling. Lobster seed smuggling has increased by the time of government policies changes. This research explains and describe government policies and regulation that related to lobster exports, identify fisher perceptions of lobster export policies and regulation, examine the impact of lobster export policies and regulation on fisher business profits and the sustainability of lobster fisheries. This research used case study method with the data collection process including interviews, direct observation, and secondary data. Descriptive analysis and profit are used to analyzing the data obtained. The results showed the perception of Palabuhanratu fisher on the implementation of the PERMEN KP policy No.17/2021 was (38%). It showed that many fisheries has negative perception of this regulation, and the remaining 58% were neutral, and 4% agreed. The uncertainty selling price of lobster juvenile from supplied to collectors, has an impact on the income value of fisher. To ensure the sustainability of the lobster fishery in Palabuhanratu was by optimizing the cultivation of lobster juvenile to adult size and accommodate the abundant catches of lobster juvenile from fisher.
Keyword: Persepsi Nelayan, Kebijakan Ekspor, Benur Lobster, Keberlanjutan Perikanan, 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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