Judul: Estimation of Sugarcane (Saccharum officinarum L.) Productivity in the ENSO Phase using Crop Simulation Model
Abstrak: Indeks kejadian ENSO menurunkan setidaknya 22% jumlah produktivitas tanaman tebu. Produktivitas tebu memiliki potensi yang lebih tinggi pada tahun normal dibandingkan dengan tahun kejadian El Nino dan La Nina. Konsumsi gula nasional tahun 2013 mencapai 3 juta ton/ha. Penelitian ini bertujuan untuk menyusun model simulasi pertumbuhan, perkembangan, dan submodel neraca air tanaman tebu untuk memperkirakan produktivitas dan kebutuhan air tanaman tebu pada tiga tahun kejadian yang berbeda (El Nino, La Nina, dan tahun normal), serta menjelaskan pengaruh variabilitas iklim seperti ENSO (El Nino Southern Oscillation) terhadap produktivitas tanaman tebu. Produktivitas tanaman tebu hasil dugaan model memiliki perbedaan dengan nilai produktivitas hasil observasi dengan nilai R2 sebesar 0,99, sedangkan nilai galatnya sebesar 2,58 % pada tahun kejadian El Nino (2015 dan 2019), 2,67% pada tahun kejadian La Nina (2010 dan 2011), dan sebesar 0,19% pada tahun normal (2013 dan 2014). Kebutuhan air tanaman tebu berkisar antara 46 – 116 mm/bulan dalam sekali masa tanam., The ENSO event index reduces the total productivity of sugarcane plants by at least 22%. Sugarcane productivity has a higher potential in normal years compared to El Nino and La Nina years. National sugar consumption in 2013 reached 3 ton/ha. This study aims to develop a simulation model for sugarcane growth, development, and water balance sub-models to estimate sugarcane productivity and water demand in three different incident years (El Nino, La Nina, and normal years), as well as to explain the effects of climate variability such as ENSO (El Nino Southern Oscillation) on sugarcane productivity. The productivity of sugarcane plants as a result of the alleged model has a difference with the observed productivity value with an R2 value of 0,99, while the error value is 2,58% in El Nino years (2015 and 2019), 2,67% in La Nina years (2010 and 2011), and by 0,19% in normal years (2013 and 2014). Sugarcane water needs range from 46 – 116 mm/month in one planting period.
Keyword: tebu, model simulasi, produktivitas, kebutuhan air, ENSO

Judul: Analisis Produktivitas dan Penentuan Masa Tanam Menggunakan Model Simulasi Pertumbuhan dan Perkembangan Tanaman Tebu
Abstrak: Peningkatan konsumsi gula nasional belum dapat diimbangi oleh produktivitas gula dalam negeri. Salah satu upaya untuk meningkatkan produksi gula nasional yaitu melalui kajian potensi sumberdaya lahan dan kesesuaian iklim dengan menggunakan model simulasi pertumbuhan dan perkembangan tanaman. Produksi tebu varietas Kidang Kencana di Kabupaten Mojokerto lebih unggul karena memiliki waktu panen yang lebih cepat serta produktivitas yang lebih besar jika di bandingkan pada produksi tebu di Kabupten Kediri. Laju perkembangan pada kejadian fenologi tanaman tebu dipengaruhi oleh akumulasi suhu udara untuk mencapai thermal unit pada fase perkembangan tanaman sedangkan bobot biomassa organ memiliki korelasi yang cukup kuat terhadap intensitas radiasi matahari yang diintersepsi pada tajuk tanaman. Pengujian hasil model dan data obesrvasi menunjukkan tingkat akurasi cukup baik dengan nilai RMSE< 30% dan R2 (koefisien determinasi) diatas 75% sehingga model simulasi ini layak dijadikan pertimbangan untuk dapat memprediksi potensi hasil dan produktivitas tanaman tebu. Analisis perubahan iklim dengan peningkatan suhu udara sebesar 0.8 – 0.7ᵒC dapat menurunkan tingkat produksi tebu sebesar 5,8 – 10,7 %.
Keyword: biomassa, model simulasi, produktivitas tebu

Judul: Algorithm Construction of HLI Hash Function
Abstrak: Cryptography is a study of mathematical techniques related to aspects of information security regarding on confidentiality, data integrity, entity authentication, and data origin authentication. Data integrity is a service, which is associated with the conversion of data carried out by unauthorized parties. To maintain data integrity, one can use hash functions. An hash function is a computationally efficient function to map an arbitrary length bitstring to a fixed length bitstring called as hash value. The use of hash function in maintaining the information integrity and authentication is in digital signatures, virus protection, and software distribution. Illustration of the hash function in the integrity and authentication of information that is emailed as follow. The sender sends the information and hash value to the recipient. If the hash value of the information is equal to the hash value that is sent by the sender, then information has not been changed. Otherwise the information has been changed. An hash function has two properties, one way and collision resistance. An hash function is called one way if it is computationally infeasible to find any input such that when given any hash value . Meanwhile an hash function is called collision resistant if it is computationally infeasible to find any two inputs where such that . The purpose of this study is to construct a HLI hash function algorithm, to analyze the speed and security of the hash functions as a results of construction. Furthermore, it is to compare it with SWIFFT. Hash function is constructed based on the result of algebraic operations on modular polynomial ringwith . Modular polynomial ring noted as is a set of all polynomials of degree at most with coefficients in . can be represented as a set of integer vector of modulo in dimension . So, it is simple to implement in a computer. In vector operations, is lattice . Furthermore, alattice that is defined from certain polynomial ring is called ideal lattice. HLI hash function is consists of addition and multiplication algorithm in the ring. Addition algorithm consists of sumation operations of modulo and multiplication consists of multiplication operations of modulo . Generally, algorithm of HLI hash function consists of multiplication operations of modulo and addition operations of modulo . However, if the input is binary number then multiplication algorithm only consists of multiplication operation of modulo , so algorithm of HLI hash function consists of multiplication operations of modulo and addtion operations of modulo . An hash function is secured if it has two properties, i.e., one way and collision resistance. HLI hash function hash is one way, it is following the proof of Micciancio. It is has collision resistant because of polynomial is irreducible over and monic. Moreover, it is proved that for every unit vector , the vector is small vector. If the input of hash function is a binary number then HLI hash function only involves addition operations of modulo . So the time that used almost same with SWIFFT. The excellence of HLI hash function is the key size smaller than SWIFFT. This effect on
Keyword: hash function, modular polynomial ring, lattice