Judul: Coastal Landscape Management in Adapting to Shoreline Changes in Samosir Island
Abstrak: Kemenparekraf menetapkan lima destinasi super prioritas di Indonesia, salah satunya adalah Danau Toba. Danau Toba dan Pulau Samosir saling berkaitan dalam menghadapi ancaman, salah satunya yaitu perubahan garis pantai. Hal ini mengakibatkan aksesibilitas, prasarana dan sarana tidak berfungsi dengan baik. Sedangkan sebagai daerah yang sedang melakukan pengembangan kawasan pariwisata, aspek aksesibilitas dan ketersediaan prasarana dan sarana sangat berpengaruh. Tujuan dari penelitian adalah; 1) menganalisis perubahan garis pantai, 2) menganalisis dampak perubahan garis pantai terhadap objek pariwisata, dan 3) menyusun rekomendasi pengelolaan lanskap pesisir. Analisis perubahan garis pantai dilakukan dengan metode spasial dan data kuantitatif, analisis dampak perubahan garis pantai diperoleh dan disajikan menggunakan metode deskriptif kualitatif, dan rekomendasi pengelolaan diperoleh menggunakan metode Strengths, Weakness, Opportunities and Threats (SWOT). Hasil penelitian menunjukkan tahun 2010 dan 2020 Danau Toba mengalami penurunan permukaan air sedalam 0.74 m. Perubahan garis pantai membuat dermaga tidak dapat berfungsi maksimal. Selain itu, prasarana dan sarana belum adaptif mengakibatkan fenomena semakin padatnya area objek pariwisata. Kondisi ini berada di kuadran III, sehingga diperlukan upaya defensif berupa peningkatan fungsi dermaga, mengevaluasi prasarana dan sarana, dan memberdayakan para pengelola dan masyarakat lokal., The Ministry of Tourism and Creative Economy has set five super priority destinations in Indonesia, one of which is Lake Toba. Lake Toba and Samosir Island are interconnected in facing threats, one of which is shoreline changes. This results in accessibility, infrastructure and facilities not functioning properly. Meanwhile, as an area that is developing a tourism area, the aspect of accessibility and availability of infrastructure and facilities is very influential. The aims of the research are; 1) analyzing shoreline changes, 2) analyzing the impact of shoreline changes on tourism objects and 3) compiling recommendations for coastal landscape management. Analysis of shoreline change was carried out using spatial methods and quantitative data, analysis of the impact of shoreline changes was obtained and presented using descriptive qualitative methods, and management recommendations were obtained using the Strengths, Weaknesses, Opportunities and Threats (SWOT) methods. The results showed that in 2010 and 2020 Lake Toba experienced a decrease in water level of 0.74 m. Changes in shoreline make the pier unable to function optimally. In addition, the infrastructure and facilities have not been adaptive resulting in the phenomenon of the increasingly dense tourism object area. This condition is in quadrant III, so defensive efforts are needed in the form of improving the function of the wharf, evaluating infrastructure and facilities, and empowering managers and local communities.
Keyword: accessibility, tourism object, infrastructure and facilities

Judul: Tata Kelola Ekowisata di Pulau Samosir, Kabupaten Samosir, Sumatera Utara
Abstrak: Danau Toba telah ditetapkan menjadi salah satu destinasi wisata super prioritas di Indonesia. Pulau Samosir yang berada ditengah kawasan Danau Toba sebagai objek unggulan wisata. Penelitian bertujuan untuk merumuskan tata kelola ekowisata di Pulau Samosir. Data dikumpulkan melalui observasi lapang, wawancara, dan penelusuran dokumen. Didapatkan 25 stakeholder yang teridentifikasi dan terdiri atas instansi pemerintah, Badan Usaha Milik Negara (BUMN), komunitas lokal, swasta, lembaga masyarakat serta masyarakat. Setiap stakeholder memiliki Tupoksi untuk instansi pemerintah daerah, serta aturan kelembagaan bagi yang lain. Dinas Pariwisata Kabupaten Samosir memiliki hubungan terbanyak dalam bentuk komunikasi, koordinasi dan bekerjasama dalam menjalankan program pengembangan wisata. Tata kelola ekowisata di Pulau Samosir dirumuskan berdasarkan prinsip good governance yaitu partisipasi, transparansi, akuntabilitas, efektifitas dan efisiensi, kepastian hokum serta responsif., Lake Toba has been designated as one of the super priority tourist destinations in Indonesia that requires accelerated tourism development. There is Samosir Island in the middle of the Lake Toba area which is one of the leading objects. The research aims to identify and classify stakeholders who have an interest and influence in tourism development, mapping relationships between stakeholders, and formulating ecotourism governance on Samosir Island. Data were collected through field observations, interviews, and document searches. There are 25 identified stakeholders consisting of government agencies, State-Owned Enterprises (BUMN), local communities, the private sector, community institutions and the community. The development of ecotourism on Samosir Island is supported by duties and functions, institutional rules. The Samosir Regency Tourism Office has the most relations in the form of communication, coordination and cooperation in carrying out tourism development programs. Ecotourism governance in Samosir Island is formulated based on the principles of good governance, participation, transparency, accountability, effectiveness and efficiency, legal certainty and responsiveness.
Keyword: development, governance, Samosir Island, stakeholders

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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