Judul: Climate Suitability On The Spread Of Brown Planthopper (Nilaparvata lugens Stal.) in Cilacap, Central Java Using Climex Model
Abstrak: Padi merupakan komoditas pangan utama di bidang pertanian yang menjadi salah satu makanan pokok bagi penduduk Indonesia. Salah satu kendala dalam meningkatkan produksi padi adalah serangan hama. Wereng batang cokelat (WBC) merupakan hama utama tanaman padi yang mudah beradaptasi di lingkungan baru. Penelitian ini bertujuan menganalisis kesesuaian iklim terhadap potensi hama WBC di Kabupaten Cilacap. Metode yang digunakan dalam penelitian ini adalah analisis regresi parameter iklim terhadap tingkat serangan hama WBC dan indeks ekoklimatik (EI) dengan menggunakan model Climex 4.0. Analisis regresi digunakan untuk melihat faktor iklim mana yang paling berpengaruh terhadap penyebaran WBC. Faktor iklim yang paling berpengaruh terhadap daerah serangan dan populasi WBC adalah kelembaban udara. Hasil analisis dari tahun 2009 hingga 2018 menunjukkan nilai EI sebesar 81 yang menunjukkan kondisi lingkungan di Kabupaten Cilacap cocok untuk perkembangan hama WBC. Hasil analisis menggunakan skenario perubahan iklim RCP 4.5 dan 8.5 pada tahun 2030 dengan model CSIRO menunjukkan nilai EI sebesar 81 dan 87. Sedangkan berdasarkan model MIROC5 menunjukkan nilai EI sebesar 82 dan 84. Hal ini menunjukkan iklim dimasa mendatang cocok untuk perkembangan hama wereng cokelat., Rice is the main food commodity in agriculture which is one of the staple foods for the Indonesian population. One of the obstacles in increasing rice production is pest attack. Brown stem planthopper (WBC) is a major pest of rice plants that is easy to adapt to new environments. This study aims to analyze the suitability of climate to potential WBC pests in Cilacap Regency. The method used in this study is a regression analysis of climate parameters on the level of WBC pest attack and the ecoclimatic index (EI) using the Climex 4.0 model. Regression analysis was used to see which climatic factors had the most influence on the spread of WBC. The most influential climatic factor on the area of attack and the population of WBC is air humidity. The results of the analysis from 2009 to 2018 show an EI value of 81 which indicates the environmental conditions in Cilacap Regency are suitable for the development of WBC pests. The results of the analysis using scenarios of climate changes in RCP 4.5 and 8.5 in 2030 with the CSIRO model show EI values of 81 and 87. Meanwhile, based on the MIROC5 model, EI values of 82 and 84 show that the future climate is suitable for the development of brown planthoppers.
Keyword: climex, perubahan skenario iklim, serangan hama, wereng batang cokelat

Judul: Analysis of Climatic Factors on Brown  Planthopper Attack in Northern Subang
Abstrak: Subang merupakan salah satu sentra produksi padi di Jawa Barat setelah Indramayu dan Karawang. Fluktuasi produksi padi tidak terlepas dari faktor iklim serta serangan hama dan penyakit. Wereng batang coklat (Nilaparvata lugens Stal.) merupakan salah satu hama berbahaya pada tanaman padi karena dapat menularkan virus lain. Pemodelan Climex digunakan untuk mengetahui respon suatu spesies terhadap komponen iklim. Penelitian ini bertujuan menganalisis dampak variabilitas dan perubahan iklim terhadap potensi serangan hama wereng batang coklat di wilayah Subang Utara. Fungsi yang digunakan dalam model Climex adalah compare years dan compare locations. Skenario iklim yang digunakan adalah RCP 4.5 dan RCP 8.5 dengan model CCSM4 dan MIROC5. Hasil penelitian menunjukkan bahwa pada tahun 2011-2020 (baseline) wilayah Subang Utara secara umum memiliki iklim yang sesuai untuk perkembangan wereng batang coklat dengan nilai EI sebesar 62. Adanya variabilitas iklim dapat berdampak pada perkembangan wereng batang coklat. Fenomena El-Nino dapat menurunkan nilai EI menjadi 46 (tahun 2015) dan 43 (tahun 2019). Terjadinya peningkatan suhu, perubahan pola curah hujan, dan naiknya permukaan laut pada tahun 2050-an dapat menurunkan nilai EI menjadi 45 dan 39 (CCSM4) serta 55 dan 50 (MIROC5)., Subang is one of the centers of rice production in West Java after Indramayu and Karawang. Fluctuations in rice production are inseparable from climatic factors and attacks by pests and diseases. Brown planthopper (Nilaparvata lugens Stal.) is a dangerous pest on rice plants because it can transmit other viruses. The Climex model is used to determine the response of a species to climate components. This study aimed to analyze the impact of climate variability and climate change on the potential attack of brown planthoppers in Northern Subang. The functions used in the Climex model are compare years and compare locations. The climate scenarios used are RCP 4.5 and RCP 8.5 with CCSM4 and MIROC5 models. The results showed that in 2011-2020 (baseline) Northern Subang had a climate suitable for the development of brown planthoppers with an EI value of 62. The existence of climate variability can have an impact on the development of brown planthoppers. Phenomenon El-Nino can decrease the EI value to 46 (in 2015) and 43 (in 2019). An increase in temperature, changes in rainfall patterns, and rising sea levels in the 2050s can decrease EI values to 45 and 39 (CCSM4) and 55 and 50 (MIROC5).
Keyword: climate change scenario, climex, compare locations, ecoclimatic index, pest suitability

Judul: Sudoku Tereduksi dan Grup Simetri Sudoku
Abstrak: Sudoku is a logic game in form of square games consisting rows, columns and mini grids. In this game, the square is filled by numbers from 1 to . At this game, the player plays the game precisely because each cell in a row or column should have a unique number. The mini grid should have no repeated numbers. This research proves that to determine the number of the isomorphic Sudoku solutions from given Sudoku solutions can be calculated using reduced Sudoku. Sudoku symmetry group is a collection of Sudoku solutions that is experienced symmetry group operations. Symmetry group operation is an operation permutation consisting permutation values, stack permutations, permutations band, column permutations on the stack, or row permutations of the band. The isomorphic Sudoku solutions from reduced Sudoku can be obtained from symmetry group operation imposed on Sudoku reduced. The total possible Sudoku solutions calculated from the number of given reduced Sudoku.
Keyword: sudoku symmetry group, reduced sudoku, isomorphic