Judul: Dampak Makroplastik Terhadap Ekosistem Mangrove di Teluknaga, Kabupaten Tangerang
Abstrak: Ekosistem mangrove sering kali menjadi tempat berakhirnya segala bahan pencemar dari daratan. Makroplastik adalah sampah terbanyak yang ditemukan di kawasan ekosistem mangrove. Penelitian ini bertujuan mengestimasi pengaruh pencemaran makroplastik terhadap kerapatan mangrove dan kelimpahan biota perairan di kawasan mangrove Tanjungburung dan Tanjungpasir, Teluknaga. Penelitian dilaksanakan di kawasan mangrove Desa Tanjungburung dan Tanjungpasir pada bulan Maret sampai April 2021. Data yang diambil meliputi jumlah individu mangrove, jenis mangrove, diameter batang mangrove, jumlah makroplastik, penutupan serta ketebalan makroplastik pada substrat, jumlah biota perairan, dan jenis biota perairan. Pengambilan contoh dilakukan secara purposive sampling berdasarkan kondisi mangrove yang seragam. Pencemaran makroplastik menyebabkan kondisi mangrove di Tanjungburung sangat buruk, walaupun kurang berpengaruh terhadap biota perairan di dalamnya. Akar mangrove yang tertutup oleh makroplastik dapat menghambat proses penyerapan air, pertukaran gas, dan fotosintesis yang terjadi pada akar mangrove. Kata kunci: Biota, makroplastik, mangrove, Mangrove ecosystems are naturally become the final destination of wastes from land. Macroplastic is the most dominant type of waste found in the mangrove ecosystem. This research aims to estimate the effect of macroplastic pollution on mangrove density and abundance of aquatic biota in the Tanjungburung and Tanjungpasir mangrove areas, Teluknaga District, Tangerang Regency. The research was carried out in the mangrove area of Tanjungburung and Tanjungpasir Village, Teluknaga District from March to April 2021. The data collected include the number of individual mangroves, mangrove species, mangrove trunk diameter, the amount of macroplastic, the cover and thickness of macroplastic on the substrate, the number of aquatic biota, and the type of aquatic biota. Sampling was carried out by purposive sampling based on uniform mangrove conditions. Macroplastic pollution causes the condition of mangroves in Tanjungburung to be very bad, although it has little effect on the aquatic biota in the ecosystems. Mangrove roots covered by macroplastic have been inhibit the process of water absorption, gas exchange, and photosynthesis that occur in mangrove roots. Keywords: Biota, macroplastic, mangrove
Keyword: Biota, macroplastic, mangrove

Judul: Kelimpahan Makroplastik dan Mikroplastik pada Sedimen di Muara Sungai Cisadane, Kabupaten Tangerang
Abstrak: Plastik merupakan jenis sampah yang paling dominan tersebar di perairan. Muara sungai merupakan bagian sungai yang paling besar menerima bahan pencemar. Sampah plastik yang berukuran makro dan mikro tersebar di permukaan dan sedimen dasar perairan, sehingga menyebabkan ketidakstabilan ekologi dan menurunkan kualitas lingkungan perairan. Penelitian bertujuan menganalisis kelimpahan makroplastik, kelimpahan mikroplastik berdasarkan tipe, warna, ukuran, dan jenis polimer pada sedimen di muara Sungai Cisadane. Pengambilan contoh dilaksanakan pada Juli-November 2018 di tiga titik muara Sungai Cisadane, Kabupaten Tangerang. Contoh mikroplastik dihitung dan diamati berdasarkan tipe, warna, ukuran, dan jenis polimer. Analisis jenis polimer dilakukan dengan menggunakan FTIR. Potongan plastik merupakan jenis makroplastik yang paling banyak ditemukan. Nilai kelimpahan mikroplastik berkisar 17448-23086 partikel kg-1 sedimen kering. Kelimpahan mikroplastik didominasi oleh tipe film berwarna hitam dan putih. Adapun ukuran mikroplastik paling banyak ditemukan pada ukuran 1 (20-40 μm) untuk tipe film dan fragmen, sedangkan tipe fiber dominan pada ukuran 14 (1000-2000 μm). Jenis polimer yang ditemukan yaitu polystyrene, acrylonitrile butadiene, polypropylene, low-density polyethylene, high-density polyethylen, latex, dan nylon. Jumlah potongan plastik paling banyak ditemukan di daerah intertidal pada bulan Juli. Kelimpahan tertinggi mikroplastik terdapat pada daerah muara di bulan November. Secara keseluruhan, kelimpahan mikroplastik didominasi oleh tipe film, kelompok warna hitam dan putih, serta kelompok ukuran 1 dan 14.
Keyword: makroplastik, mikroplastik, muara sungai, pengelolaan, polimer

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