Judul: Studi Kasus di Dataran Tinggi Dieng Wonosobo
Abstrak: Meningkatnya permintaan produksi kentang di Dieng menjadi daya tarik dan mendorong petani untuk terus memperluas lahannya. Data Kantor Lingkungan Hidup Kab. Wonosobo (2002) menyebutkan dari luas hutan tanaman akasia di Kec. Kejajar seluas 1.158,5 ha sekitar 522,25 ha telah dijarah untuk dijadikan lahan pertanaman kentang. Mengingat pentingnya peranan binatang tanah terutama bagi kesuburan tanah maka dilakukan penelitian dengan tujuan menetapkan peringkat keanekaragaman binatang tanah pada lahan pertanaman kentang dan lahan hutan tanaman akasia serta menetapkan faktor lingkungan yang berpengaruh terhadap populasi binatang tanah (fisik-kimia tanah dan bahan pencemar tanah). Pengambilan contoh tanah dan binatang tanah dilakukan pada bulan Agustus 2003. Analisis tanah dan bahan pencemar tanah pada bulan Agustus 2003-Januari 2004. Penetapan peringkat keanekaragaman binatang tanah dengan skoring indeks kekayaan jenis Marglef, indeks kelimpahan jenis Shanon-Wiener dan indeks kemerataan jenis Evennes sedangkan penetapan fisik-kimia tanah dengan regresi linier berganda dan bahan pencemar tanah secara deskriptif melalui studi literatur, wawancara serta uji laboratorium.
Keyword: 

Judul: Analisa produksi pertanian dan evaluasi keadaan lingkungan biofisik di dataran tinggi Dieng
Abstrak: Dataran tinggi Dieng termasuk daerah aliran sungai Serayu bagian hulu, dan merupakan bagian dari wilayah Kabupa ten Wonosobo, Propinsi Jawa Tengah. Penelitian ini bertujuan untuk mengetahui produk:si beberapa jenis tanaman pertanian, menentukan ratio antara produksi pertanian dengan standar kebutuhan kalori serta faktor-faktor yang mempengaruhinya. Di samping itu dievaluasi juga keadaan lingkungan biologis dan fisik sehubungan dengan aktivitas pertanian di dataran tinggi Dieng. Rata-rata produksi total tanaman pertanian yang diusahakan oleh petani di daerah penelitian sebesar 6 280 027.5 kcal/ha/th. Produksi tersebut dapat mencuk:upi standar kebutuhan kalori (2 200 kcal/jiwa/hari) sejumlah 7.8 jiwa/ha atau untuk tiap jiwa dapat tercukupi oleh lahan pertanian seluas 0.128 ha. Namun rata-rata kepadatan agrarisnya sebesar 10.; jiwa/ha, hal ini berarti untuk setiap jiwa hanya tersedia lahan seluas 0.097 ha. Kenyataan tersebut menunjukkan bahwa dengan produksi yang telah dicapai dan kondisi kepadatan agrarisnya, maka standar kebutuhan kalori dalam menu penduduk tidak dapat tercukupi. ...
Keyword: 

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