Judul: Analysis of Mangrove Damage and Rehabilitation Steps in the Angke Kapuk Protected Forest, North Jakarta
Abstrak: Ekosistem mangrove merupakan salah satu habitat alami pada kawasan pesisir yang sangat rentan terhadap ancaman alam baik dari darat maupun laut. Selain disebabkan oleh alam, ancaman terhadap ekosistem mangrove juga dapat disebabkan oleh kegiatan manusia. Penelitian ini bertujuan untuk menganalisis tingkat kerusakan mangrove dan potensi rehabilitasi mangrove di Hutan Lindung Angke Kapuk, Jakarta Utara. Penelitian ini dilaksanakan pada bulan Desember 2021 hingga Januari 2022 dengan lokasi penelitian terdiri dari tiga stasiun yang meliputi tiga tipe yaitu teluk, muara sungai, dan pantai reklamasi. Kerapatan dan penutupan mangrove di Angke Kapuk tergolong dalam kriteria rendah, kecuali stasiun 1 yang memiliki kerapatan sangat tinggi dan penutupan mangrove dalam kriteria rendah. Kondisi ini mengakibatkan nilai indeks kesehatan mangrove menjadi sedang pada stasiun 1, sedangkan stasiun 2 dan 3 tergolong kategori rendah. Indeks kualitas lingkungan pada ketiga stasiun tergolong kedalam kategori tinggi. Berdasarkan nilai kedua indeks tersebut, tingkat kerusakan pertumbuhan mangrove tergolong tinggi dan kerusakan lingkungan mangrove tergolong rendah dan diketahui matriks rehabilitasi mangrove dengan strategi replantasi. Strategi replantasi tersebut mempertimbangkan zonasi dalam penentuan jenis mangrove yang ditanam., Mangrove , one of the natural ecosystems in coastal areas is very vulnerable to n threats both from land and sea. Besides being caused by nature, threats to mangrove ecosystems can also be caused by human activities. This study aims to analyze the level of damage to mangroves and the potential for mangrove rehabilitation in the Angke Kapuk Protection Forest, North Jakarta. This research was carried out from December 2021 to January 2022 with research locations consisted of three stations covering three types, namely bays, river mouths, and reclamation beaches. The density and cover of mangroves in Angke Kapuk are classified as low criteria, except for station 1 which has a very high density and mangrove cover is in the low criteria. This condition causes the mangrove health index value to be moderate at station 1, while stations 2 and 3 are in the low category. The environmental quality index at the three stations belongs to the high category. Based on the values of these two indices, the level of damage to mangrove growth is classified as high and environmental damage to mangroves is classified as low and it is known that the mangrove rehabilitation matrix with a replantation strategy. The replantation strategy considers zoning in determining the type of mangrove to be planted
Keyword: kesehatan mangrove, kualitas lingkungan, mangrove, rehabilitasi, environmental quality, mangrove health, rehabilitation, mangroves

Judul: Strategi Rehabilitasi Ekosistem Mangrove Melalui Analisis Tingkat Kerusakan di Suaka Margasatwa Muara Angke Provinsi DKI Jakarta.
Abstrak: The phenomenon of mangrove degradation that occurred in the last decade at Muara Angke Sanctuary is caused by various factors, such as land conversion to ponds for aquaculture, pollution, sedimentation, and variety of human activities around. Most of rehabilitation conducted in this area to recover mangrove ecosystem. Unfortunately, it had not yet significantly give positive impacts as wishes. The aim of this study are to analyze mangrove damaged level dan damaged rate, evaluate previous rehabilitation, and formulate strategy for mangrove rehabilitation. This study uses a mangrove vegetation analysis method, aquatic environment analysis, quesionaire analysis and interviews, and Landsat Image analysis. The results of this study classifiy mangrove vegetation in this area to very high density (2,82 ha or 37% of mangrove area), rare or damaged (1,23 ha or 16% of mangrove area) and damaged heavily (3,62 ha or 47% of mangrove area). Damaged rate of mangrove vegetation is 0,569 ha/year. Rehabilitation in this area have not yet significantly influence to mangrove ecosystem. Recommended strategy of rehabilitation according to this research are strategy for ecology, policy, sosial and economy.
Keyword: mangrove, degradation, damaged analysis, rehabilitation, strategy

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
Keyword: