Judul: Water Footprint Analysis of Paddy Cultivation Using Subsurface Irrigation in a Greenhouse
Abstrak: Air menjadi salah satu unsur pokok yang dibutuhkan tanaman padi untuk tumbuh dan berkembang. Banyaknya kebutuhan air dalam menghasilkan produk dapat dikaji dengan pendekatan water footprint. Penelitian ini bertujuan menganalisis nilai water footprint budidaya padi dengan berbagai perlakuan pada kondisi lahan. Penelitian dilakukan di dalam greenhouse Kinjiro Farm, Gunung Batu pada bulan Maret hingga Juli 2022. Terdapat tiga perlakuan pada kondisi lahan berdasarkan ketinggian muka airnya yaitu sistem irigasi tergenang (IT) dengan permukaan air berada di atas permukaan tanah, irigasi basah (IB) dengan permukaan air sejajar dengan permukaan tanah, dan irigasi kering (IK) dengan permukaan air berada di bawah permukaan tanah. Nilai water footprint IT, IB, dan IK berturut-turut sebesar 1,92 m3/kg, 1,66 m3/kg, dan 6,14 m3/kg. Nilai produktivitas air tertinggi dihasilkan oleh IB sebesar 0,60 kg/m3. Rata-rata pertumbuhan tinggi padi, jumlah daun, dan jumlah anakan padi tertinggi terjadi pada perlakuan IB. Perlakuan IB merupakan perlakuan jenis kondisi lahan yang paling optimum dalam budidaya padi di dalam greenhouse., Water is one of the basic elements for rice plants to grow and develop. Total of water requirements in producing products can be assessed using the water footprint approach. This study aimed to analyze the value of the water footprint in paddy cultivation with various scenarios. The study was conducted in the Kinjiro Farm greenhouse, Gunung Batu from March to July 2022. There were three treatments on land conditions based on the water level, namely the flooded irrigation system (IT) with water surface higher than the soil surface, wet irrigation (IB) with water surface as high as the soil surface, and dry irrigation (IK) with water surface lower than the soil surface the soil surface. The water footprint values of IT, IB, and IK were 1,92 m3/kg, 1,66 m3/kg, dan 6,14 m3/kg, respectively. The highest water productivity value was produced by IB at 0,60 kg/m3. The highest average growth of rice height, number of leaves, and number of tillers occurred in the IB field scenario. The IB scenario is the most optimum type of land condition scenario for rice cultivation in a greenhouse.
Keyword: dry irrigation, flooded irrigation, greenhouse, water footprint, wet irrigation

Judul: Analysis of Water Footprint and Carbon Footprint with Automation Systems Under Surface Irrigation Model for Rice Cultivation
Abstrak: Kesulitan dalam memperhatikan kondisi lingkungan pada budidaya padi konvensional dapat menyebabkan penggunaan air menjadi tidak efisien. Sektor pertanian menyumbang 14% emisi gas rumah kaca dunia. Irigasi cerdas merupakan salah satu solusi yang dapat menghemat penggunaan air namun turut menyumbangkan emisi gas rumah kaca. Penelitian ini bertujuan menganalisis kinerja sistem irigasi otomatis, water footprint, dan carbon footprint dari otomatisasi irigasi bawah permukaan berbasis internet of thing pada lahan padi. Penelitian diawali dengan persiapan lahan, pengumpulan data primer dan data sekunder, serta analisis water footprint dan carbon footprint. Analisis dilakukan berdasarkan data harian yang digunakan selama masa tanam. Perhitungan water footprint meliputi perhitungan green, blue, dan grey water footprint. Kinerja sistem irigasi otomatis musim tanam pertama cukup baik dengan 88,43% data berada pada rentang set point atas dan bawah. Besar water footprint dan carbon footprint yang dihasilkan dari proses irigasi bawah permukaan otomatis untuk menghasilkan produk padi berturut-turut sebesar 54.731,92 m3/ton dan 30,4 kgCO2-eq/tahun. Difficulties monitoring to environmental conditions in conventional rice cultivation can cause irrigation to be inefficient. The agricultural sector produces 14% of the world's greenhouse gas emissions. Smart irrigation is one solution that can save water use but also contribute to greenhouse gas emissions. This study aims to analyze the automatic irrigation system, water footprint, and carbon footprint of internet-based subsurface irrigation automation in rice fields. The research started with land preparation, primary and secondary data collecton, and analysis of water footprint and carbon footprint. The analysis was carried out based on the daily data used during the planting period. The calculation of the water footprint includes the calculation of green, blue, and gray water footprints. The performance of the automatic irrigation system for the first planting season was quite good with 88.43% of the data in the upper and lower set point ranges. The water footprint and carbon footprint resulting from the automation under surface irrigation process to produce rice products are 54,731.92 m3/ton and 30.4 kgCO2-eq/year, respectively., Difficulties monitoring to environmental conditions in conventional rice cultivation can cause irrigation to be inefficient. The agricultural sector produces 14% of the world's greenhouse gas emissions. Smart irrigation is one solution that can save water use but also contribute to greenhouse gas emissions. This study aims to analyze the automatic irrigation system, water footprint, and carbon footprint of internet-based subsurface irrigation automation in rice fields. The research started with land preparation, primary and secondary data collecton, and analysis of water footprint and carbon footprint. The analysis was carried out based on the daily data used during the planting period. The calculation of the water footprint includes the calculation of green, blue, and gray water footprints. The performance of the automatic irrigation system for the first planting season was quite good with 88.43% of the data in the upper and lower set point ranges. The water footprint and carbon footprint resulting from the automation under surface irrigation process to produce rice products are 54,731.92 m3 /ton and 30.4 kgCO2-eq/year, respectively.
Keyword: carbon footprint, smart irrigation, rice, water footprint

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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