Judul: Studi Keberadaan Seroja (Nelumbo nucifera Gnertner) dan Faktor Fisika-Kimi di Perairan Situ Burung, Dramaga, Kabupaten Bogor
Abstrak: Situ Burung terletak di Desa Cikarawang, Kecamatan Dramaga, Kabupalen Bogor. Pada tahun 2002 dan 2003 telah dilakukan pengerukan dasar situ dan pembersihan situ ciari gulma air seperti kayu apu. Namun kemudian vegetasi yang tumbuh adalah Ne/umbo nuciJera 0 Gaertner yang dikenal sebagai lotus atau seroja. Pada saat ini seroja lumbuh dominan dan membentuk vegetasi litoral situ. Hal tersebut menunjukkan bahwa situ Burung merupakan habitat yang cocok untuk seroja dan mal11pu mendukung kehidupan serta pertumbuhannya. Penelitian ini bertujuan untuk l11elihat faktor-faktor fisika-kil11ia yang berpengaruh terhadap keberadaan dan pertumbuhan seroja di perairan Situ Burung. Tujuan selanjutnya adalah melihat pertumbuhan populasi seroja dan persentase pcnutupannya terhadap luasan penllukaan Situ Burung. Hasil dari penelitian ini diharapkan dapat mcmberikan informasi sebagai bahan acuan dan masukan dalal11 merumuskan kebijakan-kebijakan unluk kelestarian dan keberianjutan pemanfaatan perairan Situ Burung lersebut. Penelitian ini dilakukan selal11a bulan februari-Maret 2004 dan mencakup dua aspek, yaitu pertumbuhan seroja dan kualitas perairan Situ Burung. Penentuan stasiun pengamatan menggunakan metode pengambilan eontoh berdasarkan pertimbangan (jugdement sampling). Pengukuran kualitas air dilakukan pada lima stasiun, terdiri atas tiga stasi un (I,ll,III,) pada zona seroja dan dua stasiun pad a zona tanpa seroja (lV, V). Parameter tisika-kimia yang diukur meliputi temperatur. kedalaman, kecerahan, kekeruhan, TSS, pH, DO, CO2 bebas, NH.j-N, N02-N, NO)-N, PO.j-P. dan substrat.
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Judul: Kajian Morfometri, Kualitas Air dan Nilai Simpanan/Stok Karbon Tanaman Seroja (Nelumbo nucifera) di Situ Burung, Kabupaten Bogor
Abstrak: Penelitian ini yang berlangsung di Situ Burung bertujuan untuk : (a) mengkaji kondisi morfometri dan kualitas perairan (b) mengkaji persentase penutupan tanaman Seroja (Nelumbo nucifera) (c) dan membuat persamaan allometrik untuk tanaman Seroja terkait dengan simpanan/stok karbon. Penelitian ini dilaksanakan di Situ Burung pada akhir Bulan November 2009 – awal Bulan Januari 2010. Metode pengambilan contoh dalam penelitian ini mengacu pada 3 aspek yaitu (1) morfometri : dimensi permukaan (Surface dimensions) dan dimensi bawah permukaan (Sub surface dimensions) (2) kualitas perairan : enam parameter fiska dan empat parameter kimia dan (3) biomassa tanaman Seroja (Nelumbo nucifera) : pengukuran berat basah, berat kering, kandungan % C-organik dan pendugaan stok karbon melalui pendekatan persamaan allometrik. Pada hasil penelitian ini didapatkan bahwa Situ Burung telah mengalami proses sedimentasi (sekitar0,34 ha) pada bagian yang tertutup oleh tanaman Seroja,. Pada musim hujan luas permukaan air Situ Burung mencapai ± 4,05 ha dan keberadaan Seroja seluas 0,46 ha cukup berpengaruh terhadap beberapa paremeter morfometri yakni panjang maksimum, Shore line, kedalaman rata-rata, volume total air dan perkembangan volume situ dll.
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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