Judul: Analisis Faktor-Faktor yang Memengaruhi Risiko Produksi Jambu Air di Kecamatan demak Kabupaten Demak
Abstrak: Kecamatan Demak adalah salah satu penghasil jambu air terbesar di Kabupaten Demak, namun produksi jambu air di Kecamatan Demak berfluktuasi, menandakan terjadinya risiko produksi. Tujuan dari penelitian ini adalah untuk menganalisis pengaruh faktor-faktor produksi terhadap risiko produksi jambu air yang dihadapi petani di Kecamatan Demak. Jumlah sampel yang digunakan dalam penelitian ini ada 40 responden. Metode yang digunakan dalam penentuan sampel adalah proportional random sampling. Penelitian ini menggunakan model Just dan Pope sebagai metode analisis data. Hasil penelitian ini menunjukkan bahwa peningkatan jumlah penggunaan pupuk dapat meningkatkan produksi jambu air secara nyata, peningkatan jumlah penggunaan pestisida dan tenaga kerja dapat meningkatkan risiko produksi secara nyata (risk inducing factor) dan peningkatan penggunaan pupuk dapat mengurangi risiko produksi jambu air secara nyata (risk reducing factor).
Keyword: jambu air, model Just and Pope, risiko produksi

Judul: The Correlation between Entrepreneur Characteristics and Water Apple Farming Performance in Demak District, Demak Regency
Abstrak: Kecamatan Demak merupakan salah satu sentra penghasil jambu air di Kabupaten Demak. Produktivitas jambu air di Kecamatan Demak mengalami fluktuasi selama beberapa tahun terakhir. Karakteristik wirausaha pada petani jambu air diduga menjadi salah satu faktor terjadinya flutuasi pada produktivitas jambu air di Kecamatan Demak. Tujuan penelitian ini adalah menganalisis hubungan karakteristik wirausaha dan kinerja usahatani jambu air di Kecamatan Demak. Penentuan sampel pada penelitian ini menggunakan teknik purposive sampling dan snowball sampling dengan jumlah 40 petani jambu air. Alat analisis yang digunakan dalam penelitian ini adalah Rank Spearman. Karakteristik wirausaha yang diteliti pada penelitian ini adalah percaya diri, inovatif, tanggung jawab, berani mengambil risiko, dan kerja keras. Pengukuran kinerja usahatani pada penelitian ini menggunakan indikator hasil produksi dan pendapatan. Hasil analisis menunjukkan bahwa kelima karakteristik wirausaha berkorelasi secara signifikan dengan kinerja usaha. Hal ini berati ketika karakteristik wirausaha petani jambu air meningkat maka kinerja usahatani akan meningkat.
Keyword: entrepreneur characteristics, farming performance, water apple, water apple farmer 

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