Judul: Kajian Potensi dan Supply-Demand Airbumi di Kecamatan Citeureup, Kabupaten Bogor
Abstrak: Human life creature else cannot life without groundwater. In Citeureup subdistrict, groundwater utilization for industry and housekeepinGunung Groundwater utilization need be increasinGunung Whereas groundwater availability be limited by nature condition in this area. Highly productive aquifer in Citeureup subdistrict is obtained from the alluvium river deposits, mainly a long both sides of Citeureup rivers, Cileungsi rivers, and Cijere riverSungai Well yield ranges between 2 and 5 l/sec in sand and gravel deposits with intergranular groundwater flow. Good quality of groundwater still found both in shallow and depth of aquifer. Based on quantity and quality of groundwater, the management of supply demand balance must be done. This study to give description about availability and demand of groundwater for supporting activity in Citeureup subdistrict.
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Judul: Analisis Ekonomi Pemanfaatan dan Pengembangan Sumberdaya Air (Studi Kasus: Kampung Cibereum Sunting, Kelurahan Mulyaharja, Kecamatan Bogor Selatan, Kota Bogor)
Abstrak: Water is the principal and essential resource for human life. The development of housing increase the competition of groundwater demand and leads to groundwater scarcity. The objectives of this research are to examine the characteristics of water resources user, to estimate the value of Willingness to Pay (WTP), to analyze the factor affect of WTP, and to examine feasibility of development clean water resservoir in Cibereum Sunting, Mulyaharja Village, South Bogor sub-district, Bogor City. This research used several analyses, such as descriptive, WTP, regression, and feasibility study. The results show that the characteristics of water users in Cibereum Sunting have revenue approximately Rp 1,000,001-Rp 2,000,000 per month, the amount of water needed are 3-4 m³/day/household, and number of water users are 5-6 person/household. The average value of WTP of water user is estimated Rp 149.05 per m³. The factors affect of WTP are age, revenue, and the amount of water needs. Based on the financial feasibility analysis for Net Present Value (NPV) is Rp 16,210,358.7; Net Benefit-Cost Ratio (Net B/C) is 1.18; and Internal Rate of Return (IRR) is 19%. Then, based on the economic feasibility analysis for NPV is Rp 38,839,914.09; Net B/C is 1.55; and IRR is 32%. It can be concluded that the development of clean water reservoir is feasible and important for continuous water supply for local people. The water resource optimal allocation policy must be established by government and stakeholders.
Keyword: Internal Rate of Return., Net Benefit-Cost Ratio, Net Present Value, Willingness to Pay, Water resource

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