Judul: Assessment Livelihood Vulnerability of Gadut Village and Kapau Village in Agam Regency
Abstrak: Daerah dataran tinggi merupakan daerah yang rentan terkena dampak perubahan iklim dikarenakan masyarakatnya sebagian besar bermata pencaharian sebagai petani. Penilaian kerentanan penghidupan masyarakat perlu dilakukan untuk memahami tingkat kerentanan suatu wilayah dan mengetahui faktor-faktor yang memengaruhi tingkat kerentanan sehingga dapat menentukan Langkah untuk menurunkan tingkat kerentanan. Kombinasi pembobotan dilakukan untuk melihat variasi hasil tingkat kerentanan berdasarkan metode pembobotan yang berbeda. Metode yang digunakan adalah LVI (termasuk LVI-IPCC) yang dikombinasikan dengan dua metode pembobotan yang berbeda, yaitu mengasumsikan semua bobotnya sama dan menggunakan Principal Component Analysis (PCA). Hasil perhitungan berdasarkan data wawancara dan kuesioner, Nagari Gadut dan Nagari Kapau tergolong kategori rentan dari semua metode. Kombinasi pembobotan yang berbeda menghasilkan tingkat kerentanan yang tidak jauh berbeda. Berdasarkan hasil analisis, langkah yang dapat dilakukan untuk menurunkan nilai kerentanan yaitu melalui program pendidikan dan pelatihan dari pemerintah. Keterlibatan pemangku kepentingan yang berkelanjutan juga sangat penting untuk memastikan keberhasilan dari rencana adaptasi. Bentuk adaptasi yang bisa dilakukan oleh petani kecil yaitu penyesuaian tanggal tanam, penggunaan varietas tanam yang tahan terhadap variabilitas iklim, mempraktikkan teknik konservasi tanah, intensifikasi pupuk, meningkatkan irigasi, dan melakukan kegiatan non-pertanian., Highland areas are vulnerable to the impacts of climate change because most of the people are farmers. A vulnerability assessment of community livelihoods needs to be conducted to understand the level of vulnerability of an area and to know the factors that affect the level of vulnerability to determine measures to reduce the level of vulnerability. A combination of weightings was conducted to see the variation in the results of the vulnerability level based on different weighting methods. The method used was LVI (including LVI-IPCC) combined with two different weighting methods, namely assuming all weights are equal and using Principal Component Analysis (PCA). The calculation results based on interview and questionnaire data, Nagari Gadut and Nagari Kapau are classified as vulnerable categories from all methods. Different weighting combinations produce levels of vulnerability that are not much different. Based on the results of the analysis, steps that can be taken to reduce the vulnerability value are through education and training programs from the government. Continuous stakeholder involvement is also significant in ensuring the success of the adaptation plan. Forms of adaptation that can be carried out by smallholder farmers are adjusting planting dates, using planting varieties that are resistant to climate variability, practicing soil conservation techniques, intensifying fertilizers, increasing irrigation, and conducting non-agricultural activities.
Keyword: Livelihood, Livelihood Vulnerability Index (LVI), LVI-IPCC, Principal Component Analysis (PCA)

Judul: Household Livelihood Vulnerability of Lobuk and Tanah Merah in Sumenep Regency to Climate Change
Abstrak: Penilaian kerentanan masyarakat terhadap perubahan iklim merupakan langkah pertama yang perlu dilakukan agar pengambilan kebijakan mitigasi dan adapatasi perubahan iklim yang diambil tepat sasaran. Penggunaan indeks komposit seperti Livelihood Vulnerability Index (LVI, termasuk di dalamnya LVI-IPCC) dan Sistem Informasi Data Indeks Kerentanan (SIDIK) menjadi alternatif metode penghitungan kerentanan karena didasarkan pada indikator-indikator yang merangkum aspek kehidupan. Penelitian ini menggunakan metode LVI dan SIDIK, dengan pembobotan indikator yang dilakukan berdasarkan rata-rata aritmetika dan Principal Component Analysis (PCA), dengan wilayah kajian Desa Tanah Merah dan Desa Lobuk di Kabupaten Sumenep. Metode indexing yang diterapkan adalah linear scoring dan quadrant indexing. Hasil perhitungan dari data wawancara rumah tangga menunjukkan bahwa berdasarkan metode LVI, LVI-IPCC, dan SIDIK, Desa Lobuk dan Tanah Merah tergolong rentan baik pada tingkat desa maupun tingkat rumah tangga. Hasil ini diperoleh pada semua kombinasi metode pembobotan dan metode indexing yang berbeda. Tiga indikator kunci yang paling memengaruhi kerentanan Desa Tanah Merah adalah rumah tangga tanpa pengelolaan sampah, rumah tangga yang tidak pernah menerima pelatihan dari pemerintah, dan rumah tangga yang tidak menerima peringatan dini bencana. Tiga indikator kunci yang memengaruhi kerentanan Desa Lobuk adalah rumah tangga yang tidak meminta pertolongan kepada pemerintah desa dalam satu tahun terakhir, rumah tangga tanpa pekarangan, dan rumah tangga yang memiliki hutang., Community vulnerability assessment is the first step required in regard to decide the mitigation and adaptation policies of climate change. The development of composite indices such as the Livelihood Vulnerability Index (LVI, including the LVI-IPCC) and the Sistem Informasi Data Indeks Kerentanan (SIDIK) is a widely-known method of calculating vulnerability since it is based on indicators that well summarizes various aspects of life. This study utilized the LVI and SIDIK methods, with indicator weighting based on the arithmetic mean and Principal Component Analysis (PCA). The study areas are Tanah Merah Village and Lobuk Village in Sumenep Regency. The indexing method applied is linear scoring and quadrant indexing. The calculation results from household interview data showed that based on the LVI, LVI-IPCC, and SIDIK methods, Lobuk and Tanah Merah villages were classified as vulnerable at both the village and household levels. These results appeared in all the different combinations of weighting and indexing methods. Three key indicators driving the vulnerability of Tanah Merah Village are households without waste management, households that have never received training from the government, and households that do not receive disaster early warning. Three key indicators driving the vulnerability of Lobuk Village are households that have not asked the village government for help in the past year, households with small land ownership, and households with debt.
Keyword: kerentanan rumah tangga, Livelihood Vulnerability Index (LVI), Sistem Informasi Data Indeks Kerentanan (SIDIK), strategi mata pencaharian, LVI-IPCC

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology