Judul: Sustainable of Fisheries Resources Skipjack (Katsuwonus pelamis) in the Banda Sea and Surrounding Province of Maluku
Abstrak: Laut Banda sebagai daerah penangkapan utama ikan cakalang di Provinsi Maluku diduga telah mengalami tekanan penangkapan. Indikasi ini terlihat dari data terbaru dari instansi terkait dan beberapa hasil penelitian terakhir. Penutupan beberapa perusahan penangkapan ikan cakalang di Laut Banda Provinsi Maluku juga menjadi indikasi merosotnya sumberdaya ini. Kondisi ini bukan hanya menjadi ancaman kelestarian sumberdaya ikan cakalang, tetapi juga ancaman bagi pertumbuhan ekonomi daerah dan pendapatan nelayan. Untuk mengatasi hal tersebut maka penentuan jumlah upaya optimum secara biologi dan ekonomi penting dilakukan. Sebagai tambahan, Provinsi Maluku yang terkenal karena kaya sumberdaya perikanan, tetapi masih banyak nelayan yang hidup dalam kemiskinanan. Apakah karena rendahnya kemampuan mereka untuk mengeksploitasi sumberdaya perikanan atau ada kebijakan pemerintah yang tidak berpihak., Banda Sea as a principal skipjack fishing areas in Maluku province is allegedly experienced fishing pressure. This indication can be seen from the latest data from relevant agencies and some results of recent researches. The closure of some skipjack companies in the Banda Sea of Maluku province is also an indication of the decline of this resource. This condition is not only a threat to the sustainability of skipjack resources, but also to economic growth in the area as well as fishermen's income. To resolve the matter, the determination of the optimum amount of both biologically and economically effort is important. In addition, the Maluku province is famous for its rich in fishery resources but many fishermen are still lived in poverty. Probably, it is because they lack of the ability to exploit fishery resources or the government policies that did not favor to them.
Keyword: Decent fishing, Fishing technology, Skipjack, Sustainable

Judul: Resource Management of Skipjack (Katsuwonus pelamis) in Pelabuhanratu, Sukabumi District, West Java
Abstrak: Katsuwonus pelamis (skipjack or Skipjack Tuna) is one of the major pelagic fish commodities in Palabuhanratu Archipelagic Fishing Port (PPN Palabuhanratu) and become important aspect in the development of fisheries industrialization especialy for non-tuna species. Geographically, Palabuhanratu bay is situated in Fisheries Management Area (WPP) 573 on Indian Ocean. As the vast waters, fisheries management can be initiated from a small area, for example in the bay area. To understand the biological characteristics of fish such as skipjack (Katsuwonus pelamis Linnaeus, 1758) is crucial information to realizing fisheries resources management in some region. This research aims to determine the weight and length relationship, size composition, growth pattern and decent size of skipjack fishing in Palabuhanratu. Data obtained from the result of landing catches in PPN Palabuanratu from December 2012 to May 2013. Through a series of data catches of skipjack during the period 2002 to 2011 estimation made for catch effort at the level of Maximum Sustainable Yields (MSY), Maximum Economic Yield (MEY) and Open Access (OA). MSY, MEY and OA are the bio-economic indicator to formulate appropriate policies for Skipjack resources management in Palabuhanratu. The research was conducted on fish landed in Palabuhanratu by using payang gear, gillnet, and trolling. From the results of the calculation of the weight and length noted that males skipjack have a negative allometric growth pattern which means that its length growing faster than its weight. While skipjack females have an isometric growth which means its length growth pattern equal to its weight. The maximum length of tuna were obtained during the study was 710 mm. Length of fish for the first gonads mature was estimated of 523 mm, with the result that so the tuna catch is a the minimum worthines of cakalang fishing was 523 mm. Recognizing these data, if compared with the size of tuna caught during the study, only 11.2 % were larger than the size of a decent catch, this is an indication of the outset of the recruitment overfishing in Palabuhanratu. Total males mortality rate (Z) was 2.0988 fish per year and for females amounted to 0.8415 per year. While the rate of exploitation of both males and females are equal to 0.9 per year. The catch and effort at the level of Maximum Sustainable Yield (MSY) are 305.283 kgs /year and 3.898 trips /year. While estimating the value of the Maximum Economic Yield (MEY) and Open Access (OA) at the level 240.380 kgs/year; 2.101 trips/ year and 303.434 kgs/year ; 4.201 trips/year. Fox models analysis shows that overfishing has occurred since 2006 with the utilization rate of 129 % as calculated in the last year (2011) has undergone economic over fishing. Some forms of fisheries management proposed in this research include: restrictions on fishing quotas at MSY level of 78,32 Kgs/Trip and to MEY 114,43 Kgs/Trip; the policy of mesh size; conservation efforts; season control / fishing areas (spawning ground and fishing ground); rotation in fishing (fishing with alternate day) ; restrictions on the issuance of fishing licenses for new fishing vessels; Co-management among stakeholders; law enforcement (enforcement) and
Keyword: Pelabuhanratu Bay, Bioecological parameters, Bioeconomics, optimization, management.

Judul: Solusi Geometri Schwarzschild untuk Dimensi 4+1 dengan Invarian Rotasi Isotropik.
Abstrak: Metrik Schwarzschild merupakan solusi eksak pertama dari persamaan medan Einstein dengan mangasumsikan metrik statik dan simetris. Metrik Schwarzschild yang ditemukan oleh Karl Schwarzschild masih dalam dimensi 3+1, namun seiring dengan teori-teori terbaru yang menunjukkan bahwa alam semesta tidak hanya di dimensi 3+1. Maka melalui penambahan dimensi, tujuan penelitian ini memperoleh solusi pada geometri Schwarzschild untuk dimensi 4+1 dengan memodifikasi koordinat bola yang invarian rotasi isotropik dan melalui penurunan rumus seperti koordinat bola, simbol Christoffel, dan tensor Ricci. Selain mendapatkan solusi ini, metrik Schwarzschild dimensi 4+1 dapat digunakan sebagai metrik dasar untuk memperoleh solusi blackhole dan wormhole pada dimensi 4+1. Hasil akhirnya, dengan memanfaatkan modifikasi koordinat bola, metrik Schwarzschild dapat dibentuk sehingga diperoleh solusi geometri Schwarzschild untuk dimensi 4+1.
Keyword: metrik Schwarzschild, persamaan medan Einstein, modifikasi koordinat bola, penambahan dimensi, invarian rotasi isotropik