Judul: Causes of Death and Mitigation on  Lobster Fry Catching (Case Study in Simpenan District, Sukabumi Regency)
Abstrak: Puerulus atau yang biasa dikenal dengan benur lobster merupakan fase transisi antara fase phyllosoma lobster dan fase juvenile lobster lobster pada life cycle lobster. Penangkapan benur lobster biasanya menggunakan jaring pocong. Kurangnya pengetahuan nelayan di Kecamatan Simpenan terkait penanganan benur lobster dibuktikan dengan fakta bahwa benur hasil tangkapan pernah mengalami kematian. Tujuan penelitian ini adalah mendeskripsikan unit penangkapan, operasional penangkapan, dan proses transportasi benur lobster dari DPI hingga pengepul; menghitung komposisi hasil tangkapan benur lobster; mengidentifikasi faktor penyebab kematian benur lobster pada operasi penangkapan serta strategi untuk menanganinya. Metode penelitian ini adalah observasi dan wawancara dengan menggunakan pendekatan teknik accidental sampling. Analisis yang digunakan ialah deskriptif dan fishbone analysis. Hasil penelitian menunjukkan bahwa alat tangkap yang digunakan adalah jaring pocong dan alat bantu berupa lampu. Operasi penangkapan benur lobster biasa dilakukan pada malam hari. Transportasi ketika operasi penangkapan biasa menggunakan styrofoam box. Komposisi hasil tangkapan utama terdiri dari benur pasir dan benur mutiara sedangkan hasil tangkapan sampingan didominasi oleh juvenile ikan dan crustacea. Strategi penanggulangan kematian benur terbagi menjadi 4; nelayan, metode, material, dan alat. Strategi tersebut diantaranya penggunaan air yang cocok sebagai media hidup benur membawa box cadangan, penyimpanan/pengondisian box menghindari perubahan parameter air, pemberian tali sumbu pada jaring., Puerulus or known as lobster fry is a transitional phase between phyllosoma and juvenile phase in the lobster life cycle. Catching lobster fry usually used pocong nets. The lack of knowledge of fishers in Simpenan Regency in handling lobster seeds causes many lobster deaths. The purpose of this study to describe the fishing unit, fishing operations, and process of transporting from fishing ground to collectors, moreover to knowing the lobster catches. Identify the lobster fry death in fishing operations and strategies to deal with it. This research method was observation and interview used accidental sampling technique. The analysis used descriptive and fishbone analysis. The results showed fishing gear used was a pocong net and a lamp. Lobster fry fishing operations are usually carried out at night. Transportation during fishing operations usually used a styrofoam box. The main catch consisted of sand and pearl fry and by-catch were dominated by juvenile fish and crustaceans. The strategy for dealing with fry mortality is divided into four namely fisheries, methods, materials, and tools. Among them are use of suitable air as a living medium for fry, bring a spare box, storage box avoids changing air parameters and presenting the wick to the net.
Keyword: fish bone analysis, lobster seeds, Panulirus Ornatus, Puerulus

Judul: Business Analysis of Catching and Sustainable  Lobster Utilization in Pangandaran Regency, West Java
Abstrak: Lobster atau udang karang merupakan salah satu komoditas perikanan unggulan pada pasar domestik maupun ekspor. Stok komoditas lobster saat ini masih bergantung pada alam. Sebagian besar di wilayah pengelolaan perairan Indonesia telah mencapai batas maksimum jumlah tangkapan yang diperbolehkan. Usaha penangkapan lobster sebagai salah satu satu pengelolaan wilayah perairan Pangandaran perlu dikaji untuk mengetahui bagaimana sumberdaya lobster dapat dimanfaatkan secara optimal dan berkelanjutan. Tujuan penelitian ini adalah: (1) mengidentifikasi kondisi biologi lobster di Perairan Kabupaten Pangandaran Jawa Barat; (2) menganalisis kondisi pemanfaatan optimal lobster di Perairan Kabupaten Pangandaran Jawa Barat; (3) menganalisis kelayakan usaha finansial penangkapan lobster di Perairan Kabupaten Pangandaran Jawa Barat; dan (4) menganalisis strategi kebijakan pengelolaan lobster secara berkelanjutan di Kabupaten Pangandaran Jawa Barat. Metode yang digunakan pada penelitian ini yaitu: (1) analisis kondisi biologi lobster; (2) analisis bioekonomi spasial; (3) cost benefit analysis; dan (4) analisis deskriptif kualitatif. Penelitian ini menunjukkan rata-rata lobster yang tertangkap di Kabupaten tidak sesuai dengan ukuran layak tangkap. Tingkat CPUE lobster memiliki nilai yang berfluktuatif, namun terjadi penurunan secara signifikan pada tahun 2021, sehingga alokasi penangkapan optimal yang direkomendasikan yaitu 396 trip/bulan. Berdasarkan hasil analisis, usaha penangkapan lobster layak untuk dijalankan. Adapun strategi kebijakan pengelolaan lobster yang dapat dilakukan agar tetap lestari yaitu dimulai dari pelarangan penangkapan benih bening lobster kemudian diikuti dengan kebijakan lainnya. Perlu dilakukan penelitian lebih lanjut mengenai laju pertumbuhan dan perkembangan biomassa lobster dan pengembangan budidaya lobster di Perairan Kabupaten Pangandaran, Jawa Barat., Lobster or crayfish is one of the leading fishery commodities in the domestic and export markets. Lobster commodity stocks are currently still dependent on nature. Most of the Indonesian water management areas have reached the maximum allowable catch. Lobster fishing as one of the management of the Pangandaran waters area needs to be studied to find out how lobster resources can be used optimally and sustainably. The aims of this study were: (1) to identify the biological conditions of lobsters in the waters of Pangandaran Regency, West Java; (2) analyzing the condition of optimal utilization of lobsters in the waters of Pangandaran Regency, West Java; (3) analyzing the financial feasibility of catching lobsters in the waters of Pangandaran Regency, West Java; and (4) analyze the policy strategy for sustainable lobster management in Pangandaran Regency, West Java. The methods used in this study were: (1) analysis of the biological conditions of the lobsters; (2) spatial bioeconomic analysis; (3) costbenefit analysis; and (4) qualitative descriptive analysis. This research shows that the average size of lobsters caught in the district is not suitable for catching size. The lobster CPUE level has a fluctuating value, but there will be a significant decrease in 2021, so the recommended optimal catch allocation is 396 trip/month the harvest season. Based on the results of the analysis, the lobster-catching business is feasible to run. The lobster management policy strategy that can be implemented to remain sustainable is to start with a ban on catching clear lobster seeds, followed by other policies. It is necessary to carry out further research regarding the growth rate and development of lobster biomass and the development of lobster cultivation
Keyword: bioeconomy, optimal fishing, sea lobster, sustainable fisheries

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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