Judul: Nature-based tourism demand at semarang city for young age group
Abstrak: Semarang city is recently known as industry and business city. It also has potentials for tourism destination areas to young age group which known as having more leisure time compare to the other age group. The objectives of this research were to identity the potential demand and actual demand of nature-based tourism of young age group (15-24 years old) at Semarang City and the influencing factors. This research was in July to September 2010 at Semarang City. The respondents were highschool students, College students and nature-based tourists. Data were collected through literature review, interviews, questionnaires. Analysis of binary logistics regression was used to determine the factors which influence potential demand. Data of Statistic Center Agency (Badan Pusat Statistik-BPS, 2008) showed that the number of young age group individuals at Semarang City was 241.474 individuals. The study showed that the potential demand of nature – based tourism for young age group at Semarang City was 198.492 individuals (82,20% of the total number of individuals of young age group). The actual demand based on tourism objects was: 14.458 individuals (beach), 9.322 individuals (cave), 7.458 individuals (waterfall), and 20.144 individuals (mountain). Farther analysis used the binary logistics regression showed that reasons of visit (beautiful scenery, enjoy the scenery and fresh air) and length of visit were the factors which influence potential demand. Meanwhile, descriptive analysis showed that the factors which influence the actual demand were parents occupation, interest foward tourism objects, reason of visit, and time of visit.
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Judul: Studi rekreasi alam yang diminati wisatawan mancanegara di kawasan konservasi di Pulau Jawa
Abstrak: Rekreasi alam sebagai salah satu produk jasa sumberdaya hutan mempunyai potensi ekonomis dan ekologis yang menguntungkan. Dari segi ekonomi merupakan potensi devisa negara, khususnya dengan sasaran wisatawan mancanegara. Sementara dari segi ekologi rekreasi alam memiliki resiko lingkungan yang kecil. Hal ini mengingat bahwa kualitas lingkungan adalah dasar untuk menarik pengunjung yang harus dijaga kelestariannya. Tujuan studi adalah untuk mendapatkan karakteristik wisatawan mancanegara dan bentuk rekreasi alam yang banyak diminati. Selanjutnya dengan hasil studi ini disarankan bentuk pengembangan rekreasi alam yang memberi kepuasan pengunjung, namun tanpa melupakan prinsip kelestarian dan secara ekonomi menguntungkan. Studi ini dilakukan dengan metode survei. Pengumpulan data dilakukan dengan menggunakan kuesioner, yang meliputi identitas wisatawan, lama dan cara kunjungan, objek dan kegiatan rekreasi yang dipilih, dan penilaian terhadap objek, fasilitas, dan layanan yang ada di lokasi. Lokasi yang dipilih adalah kawasan konservasi yang memiliki wilayah khusus sebagai zona rekreasi dan merupakan kawasan yang cukup berkembang, yaitu Taman Nasional Bromo Tengger Semeru, TN Baluran, TN Meru Betiri, CA/TW Pangandaran, dan TN Ujung Kulon. Rekreasi alam sebagai kegiatan yang memiliki tantangan ternyata lebih diminati wisatawan muda yang berusia 20- 39 tahun, sesuai semangat dan jiwa muda mereka yang menyukai tantangan. Mereka kebanyakan adalah para profesional dan pelajar/mahasiswa yang selain berekreasi juga ingin menambah pengalaman dan wawasan. Sebagian besar dari mereka berasal dari Eropa Barat dan Amerika Utara, dan pada umumnya adalah wisatawan laki-laki.
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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