Judul: Fertilization Management of Palm Oil (Elaeis guineensis Jacq.) in Negeri Lama Selatan Estate, PT Hari Sawit Jaya, Labuhanbatu, North Sumatera
Abstrak: Kelapa sawit merupakan tanaman perkebunan penting yang potensial untuk dibudidayakan. Pemeliharaan pada tanaman kelapa sawit khususnya pemupukan memerlukan biaya yang tinggi sehingga perlu diperhatikan peningkatan efisiensi dan efektivitas pada penerapannya. Kegiatan magang dilaksanakan di Kebun Negeri Lama Selatan, PT Hari Sawit Jaya, Labuhanbatu, Sumatera Utara yang berlangsung dari Januari-Mei 2022. Kegiatan magang bertujuan untuk mempelajari dan menganilisis sistem manajemen pemupukan kelapa sawit yang efektif dan efisien. Pengamatan pada manajemen pemupukan dilakukan pada penerapan kaidah 5T (tepat jenis, tepat dosis, tepat cara, tepat waktu dan tepat tempat). Berdasarkan hasil pengamatan, manajemen pemupukan di Kebun Negeri Lama Selatan sudah dijalankan dengan baik sesuai dengan standar yang ditetapkan oleh perusahaan. Penerapan sistem tempat pengeceran pupuk meningkatkan kualitas pemupukan dan mempermudah proses pelangsiran pupuk. Ketepatan dosis aplikasi pupuk pada pemupukan HGFB (High Fertilizer Borate) mencapai persentase 95.50% dan pada pemupukan MOP (Muriate of Potash) mencapai persentase dan 92.80%. Realisasi aplikasi pupuk sudah sesuai dengan rekomendasi waktu pemupukan. Cara pengaplikasian pupuk juga sudah baik, ratarata persentase tepat cara pemupukan HGFB dan MOP yaitu 95,50% dan 92,10%. Tempat pemupukan juga sudah diaplikasikan sesuai standar perusahaan, rata-rata jarak aplikasi pupuk dari pokok pada pemupukan HGFB dan MOP yaitu 54,88 cm dan 52,90 cm., Palm oil is an important plantation crop that has the potential to be cultivated. Maintenance of palm oil, especially fertilization, requires high costs, so its necessary to pay attention to increasing efficiency and effectiveness in its application. The internship was conducted on January to June 2022 at Negeri Lama Selatan Estate, North Sumatera. The internship activity aims to study and analyze an effective and efficient oil palm fertilization management system. Observations on fertilization management were carried out on the application of the 5T rule (right type, right dose, right method, right time and right place). Based on observations, fertilization management in Negeri Lama Selatan Estate has been carried out well according to the standards set by the company. The application of a fertilizer retailing system improves the quality of fertilization and simplifies the process of fertilizer distribution. The accuracy of fertilizer application dose on HGFB (High Grade Fertilizer Borate) fertilization reached the percentage of 95.5% and the MOP (Muriate of Potash) fertilization reached the percentage and 92.80%. The realization of fertilizer application is in accordance with the recommended time of fertilization. The method of applying fertilizer is also good, the average persentation of HGFB and MOP fertilization methods is 95.50% and 92.10%, respectively. The place of fertilization has also been applied according to company standards.
Keyword: cara pemupukan, efisiensi pemupukan, ketepatan pemupukan, fertilizer accurancy, fertilizer application, fertilizer efficiency

Judul: Fertilization Management of Palm Oil (Elaeis guineensis Jacq.) in Tandun Estate, PT Perkebunan Nusantara V, Kampar, Riau
Abstrak: Kegiatan magang dilaksanakan di Kebun Tandun, PTPN V pada tanggal 24 Januari hingga 24 Mei 2022. Kegiatan pemupukan sebagai salah satu kegiatan pemeliharaan dapat menjadi upaya dalam peningkatan produktivitas kelapa sawit. Efisiensi dan efektivitas pemupukan dapat tercapai dengan penerapan konsep lima tepat (5T) yaitu tepat jenis, tepat dosis, tepat waktu, tepat cara, dan tepat sasaran. Tujuan kegiatan magang untuk mempelajari manajemen pemupukan pada tanaman kelapa sawit yang berlokasi di Kebun Tandun, PT Perkebunan Nusantara V, Kabupaten Kampar, Riau. Hasil pengamatan menunjukkan bahwa pelaksanaan pemupukan sudah didasarkan pada kaidah 5T (tepat jenis, tepat dosis, tepat waktu, tepat cara, dan tepat tempat) dan sesuai dengan standar yang terdapat dalam Instruksi Kerja (IK) perusahaan, terlihat dari seluruh ketepatan mencapai nilai >90%. Ketidaksesuaian waktu pemupukan dengan rencana diakibatkan oleh tidak tersedianya pupuk di gudang. Perusahaan juga telah melaksanakan pemupukan sesuai dengan kriteria ISPO dan RSPO., The internship activity was carried out at Tandun Estate, PTPN V from January 24 to May 24, 2022. Fertilization activities as one of the maintenance activities can be an effort to increase palm oil productivity. The fertilization efficiency and effectiveness can be achieved by applying the rules of 5 Tepat (5T), namely the right type, the right dose, the right time, the right method, and the right place. The internship aimed to study the fertilization management on palm oil plantations in Tandun Estate, PT Perkebunan Nusantara V. Observations showed that the application of fertilization was based on the 5T rules (right type, right dose, right time, right method, and right place) and in accordance with the company’s standards operation procedures, seen from all accuracy reaching a value of >90% . The mismatch of fertilization time with the plan was caused by the unavailability of fertilizer in the warehouse. The company has also maintained the application of fertilization in accordance with ISPO and RSPO criteria.
Keyword: ISPO, kaidah 5T, RSPO

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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