Judul: Management of Hawksbill Turtle Egg Hatching, Rearing, and Welfare in Karimunjawa National Park
Abstrak: Taman Nasional Karimunjawa (TNKJ) merupakan kawasan konservasi yang menjadi tempat penyebaran dan peneluran penyu. Penelitian bertujuan menganalisis manajemen penetasan telur dan tingkat keberhasilan penetasan telur, pemeliharaan penyu sisik dan menilai tingkat kesejahteraan tukik penyu sisik, serta menilai tingkat keberhasilan manajemen pelestarian penyu sisik dilihat dari aspek teknis pengelolaannya di Penetasan Semi Alami TNKJ. Penelitian ini dilakukan dengan metode observasi lapang, wawancara, dan studi literatur. Persentase keberhasilan penetasan telur memiliki rata-rata 47,4 % dan dilakukan uji SPSS dengan taraf kepercayaan 95 % menunjukkan hasil persentase keberhasilan telur di musim hujan dan kemarau tidak terdapat perbedaan yang signifikan. Kesejahteraan satwa di Penetasan Semi Alami TNKJ memiliki nilai sebesar 56,5% dengan kategori butuh pembinaan. Tingkat keberhasilan manajemen pemeliharaan penyu sisik di Penetasan Semi Alami TNKJ memiliki nilai 73,75 % dengan kategori B. Tingkat kegagalan penetasan telur yang berada di Penetasan Semi Alami TNKJ memiliki skor empat dikarenakan tingkat kematian sebesar >40 %. Dibutuhkan perbaikan dalam pengelolaan agar meningkatkan proses pemeliharaan., Karimunjawa National Park (TNKJ) is a conservation area where turtles spread and nest. The research aims to analyze egg hatching management and the success rate of hatching eggs, rearing hawksbill turtles and assessing the welfare level of hawksbill turtle hatchlings, as well as assessing the success level of hawksbill turtle conservation management seen from the technical aspects of management at the TNKJ Semi-Natural Hatchery. This research was conducted using field observation, interviews and literature study methods. The percentage of egg hatching success averaged 47.4% and the SPSS test was carried out with a confidence level of 95% showing that there was no significant difference in the percentage of egg success in the rainy and dry seasons. Animal welfare at the TNKJ Semi-Natural Hatchery has a score of 56.5% in the need for guidance category. The success rate of hawksbill rearing management at the TNKJ Semi-Natural Hatchery has a score of 73.75% with category B. The failure rate for egg hatching at the TNKJ Semi-Natural Hatchery has a score of four due to the mortality rate of >40%. Improvements are needed in management to improve the maintenance process.
Keyword: tingkat keberhasilan manajemen, tingkat kesejahteraan, penetasan telur, penyu sisik

Judul: Utilisation Management and Perception of  Community and Visitors in Turtle Conservation in Karimunjawa National Park
Abstrak: Karimunjawa merupakan habitat penyu sisik dan penyu hijau sebagai satwa yang dinyatakan hampir punah. Penelitian bertujuan mengidentifikasi dan mendeskripsikan manajemen pemanfaatan, persepsi, serta menganalisis kesediaan membayar masyarakat dan pengunjung dalam mendukung konservasi penyu hijau dan penyu sisik. Data dikumpulkan dengan metode observasi lapang, wawancara, dan pengisian kuesioner. Hasil penelitian menunjukkan bahwa bentuk manajemen pemanfaatan penyu di TNKJ adalah melalui program Penetasan Semi Alami (PSA) Penyu, yakni penetasan telur dan pemeliharaan untuk dilepasliarkan guna menjaga kelestarian penyu di alam, serta penunjang ilmu pengetahuan dan teknologi konservasi, pendidikan, penelitian dan wisata. Terdapat empat kategori responden yang diwawancarai, yakni 1) masyarakat nelayan, 2) masyarakat non-nelayan, 3) pengunjung PSA, dan 4) pengunjung non-PSA yang secara keseluruhan memiliki persepsi positif dengan kategori sangat baik terkait konservasi, pemanfaatan, dan upaya pelestarian penyu melalui program PSA di TNKJ serta memiliki nilai rata rata Willingness to Pay (WTP) dalam mendukung konservasi penyu sebesar Rp 14.924., Karimunjawa is the habitat of hawksbill and green turtles, which are endangered species. The study aims to identify and describe the use management, perception, and analyse the willingness to pay of the community and visitors in supporting the conservation of green and hawksbill turtles. Data were collected using field observation, interviews, and questionnaires. The results showed that the management of sea turtle utilisation in TNKJ is through the Turtle Semi-Natural Hatchery (PSA) programme, which is the hatching of eggs and rearing for release to preserve sea turtles in nature, as well as supporting science and technology conservation, education, research and tourism. There are four categories of respondents interviewed, namely 1) fishing communities, 2) non-fishing communities, 3) PSA visitors, and 4) non-PSA visitors who overall have positive perceptions with very good categories related to sea turtle conservation, utilisation, and conservation efforts through the PSA programme in TNKJ and have an average Willingness to Pay (WTP) value in supporting sea turtle conservation of Rp 14.924.
Keyword: Karimunjawa, Kesediaan membayar, Pemanfaatan, Penyu, Persepsi

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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