Judul: Pengelolaan Gulma pada Pertanaman Teh (Camellia sinensis (L.) O. Kuntze) di Unit Perkebunan Bedakah, PT Tambi Wonosobo, Jawa Tengah.
Abstrak: Kegiatan magang telah dilaksanakan di Unit Perkebunan Bedakah pada bulan Februari sampai Juni 2018. Pengamatan meliputi kondisi umum, pengelolaan kerja, metode pengendalian, alat pengendalian, jenis herbisida, dosis herbisida, waktu aplikasi herbisida, efisiensi metode pengendalian, dan kapasitas penyemprot. Hasil pengamatan menunjukkan bahwa kondisi umum gulma antar blok cenderung heterogen dengan gulma paling dominan berupa Selaginella plana. Pengelolaan kerja telah menerapkan perencanaan, pengorganisasian, pelaksanaan, dan pengawasan. Metode pengendalian gulma dilakukan dengan tiga metode. Syarat minimal alat pelindung diri (APD) belum dipatuhi sepenuhnya. Jenis herbisida sistemik berbahan aktif isopropilamina glifosat 486 g l-1. Waktu aplikasi herbisida kurang sesuai rekomendasi, kecuali pada Blok Bismo dan Blok Argopuro. Metode pengendalian kimiawi lebih efisien dibandingkan pengendalian manual berdasarkan biaya operasi. Kapasitas penyemprot berumur 17 – 29 tahun tidak menunjukkan perbedaan dengan penyempot berumur 30 – 41 tahun, hasil yang sama ditunjukkan pada kapasitas penyemprot berpengalaman kerja di bawah 2 tahun dan lebih dari 2 tahun.
Keyword: dosis, herbisida, kapasitas penyemprot, metode kuadrat

Judul: Dominansi Gulma dan Pengendaliannya pada Berbagai Tahun Pangkas Tanaman Teh (Camellia sinensis (L.) O. Kuntze) di Kebun Gambung, Pusat Penelitian Teh dan Kina, Bandung
Abstrak: Proses pemeliharaan teh tidak lepas dari pengendalian gulma. Pengendalian gulma perlu dilakukan untuk membatasi investasi gulma sehingga tanaman dapat dibudidayakan secara produktif dan efisien. Dominansi gulma dapat membantu mengidentifikasi gulma di suatu areal sehingga pengendalian gulma dapat dilakukan secara efektif dan efisien. Hasil pengamatan menunjukkan bahwa gulma dominan yang tumbuh pada TP 1 didominansi Commelina benghalensis, TP 2 didominansi Mitracarpus hirtus, TP 3 dan TP 4 didominansi Ageratum conyzoides. Nilai koefisien komunitas antar tahun pangkas <70% artinya heterogen. Pengendalian gulma manual menggunakan parang dan kimiawi menggunakan knapsack sprayer. Herbisida yang digunakan berbahan aktif Isopropilamina glifosat dengan dosis berkisar 2–3 l ha-1. Pekerja pengendalian gulma kimiawi belum mematuhi kelengkapan Alat Pelindung Diri (APD) yang telah ditetapkan perusahaan. Pengendalian gulma kimiawi lebih efisien dibandingkan manual baik dari segi biaya maupun tenaga kerja
Keyword: Commelina benghalensis, community coefficient, efficient, glyphosate, PPE

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