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: Permintaan ekowisata wisatawan mancanegara di taman nasional Bromo Tengger Semeru Jawa Timur
Abstrak: Indonesian government through Ministry of Culture and Tourism has set year of 2008 as Indonesian visit year which target of international tourists visit amount of 7 million tourists. However, eventhough the target has set up, Indonesia still lack of data regarding tourism demand especially for ecotourism. Nowadays, ecotourism has become a trend and interesting for many tourists so can attract more international tourists to come. Bromo Tengger Semeru National Park (BTSNP) is one the most familiar Indonesian ecotourism destination. This research aims to get the illustration about international tourists demand at BTSNP. Research was conducted by interviewing internationals visitor. The election of respondents used purposive sampling technique. Collected data was descriptively analyzed. Some finding of this research are: international tourists visited BTSNP dominated by Dutch tourists (32%), man (61%), university graduated (69%), unmarried (63%), 25-31 years old (36%), employment (71%), using rent transportation (loo%), the activity was to see the crater of Bromo (100 tourists), duration of stayed was 1 day (60%), period of visitation was during vacation day (99%), group tour @I%), stayed on the hotel (91%), first visitation (95%), motivation was sightseeinglvacation (47%) and media as a source of information (54%).
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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