Judul: Willingness to Pay Analysis and Strategy for Fulfilling Community Needs for Clean Water in Setrorejo Village, Baturetno District, Wonogiri Regency
Abstrak: Desa Setrorejo merupakan salah satu desa di Kecamatan Baturetno yang masyarakatnya masih mengandalkan air tanah sebagai sumber air dalam kehidupan sehari-harinya. Desa Setrorejo yang wilayahnya merupakan kawasan karst dan perbukitan menyebabkan terdapat beberapa permasalahan dalam sumberdaya air. Permasalahan sumberdaya air yang terjadi yaitu kualitas air yang kurang baik dan penurunan kuantitas air saat musim kemarau. Tujuan dari penelitian ini adalah mengestimasi besarnya nilai Willingness to pay (WTP) masyarakat terhadap air bersih dan mengidentifikasi faktor-faktornya serta menganalisi strategi pemenuhan kebutuhan air bersih untuk masyarakat. Metode pada penelitian ini adalah analisis willingness to pay menggunakan CVM, analisis regrsi logistik, dan Analitycal Hierarchy Process (AHP). Hasil penelitian menunjukkan nilai WTP yang didapatkan sebesar Rp 4.478. Faktor-faktor yang berpengaruh signifikan terhadap keputusan membayar ialah nilai penawaran, pendapatan, dan kualitas air tanah. Alternatif strategi yang dapat dilakukan dalam pemenuhan kebutuhan air bersih yaitu pengembangan infrastruktur air yang dapat dilakukan melalui pengembangan ditribusi jaringan PDAM. Nilai WTP yang didapatkan lebih besar dari nilai penawaran terendah yang berupa tarif PDAM dengan pemakaian air sampai 10m3 menggambarkan masyarakat bersedia melakukan perbaikan kualitas lingkungan dengan pendekatan pemasangan jaringan PDAM., Setrorejo village is one of the villages in Baturetno District where the people relies on groundwater as a source of water in their daily lives. Setrorejo village whose territory is a karst and hilly area causes several problems in water resources. Water resource problems that occur are deficient water quality and decrease water quantity during the dry season. The aims are to estimate the value of Willingness to Pay towards a clean water and indentify the factors and analyze the strategy for fulfillment the needs of clean water for the people. Methods that used in this research are willingness to pay using CVM, logistic regression analysis, and Analytical Hierarchy Process (AHP). The results in this research show that the obtained WTP value was IDR 4.475. The factors that have an significant influence are bid value, income, and groundwater quality. An alternatif strategy that can be done to fulfillment the need for clean water is the development of water infrastructure which can be done by developing the distribution of PDAM. The obtained WTP value is bigger that the lower bid value in the form of a PDAM tariff with water usage up to 10m3 illustrates that the people is willing to improve environmental quality by PDAM installation approach.
Keyword: CVM, AHP, PDAM, Logistic regression

Judul: Analisis Willingness to Pay Masyarakat terhadap Air Bersih di Perumahan XYZ Kotamadya Bogor
Abstrak: Perumahan XYZ merupakan perumahan yang masih mengandalkan air tanah sebagai sumber kebutuhan air sehari-harinya. Permasalahan sumberdaya air yang terjadi adalah kekeringan akibat debit air yang menurun dan resiko air tanah tercemar. Tujuan utama dari penelitian adalah mengestimasi besarnya nilai Willingness to Pay (WTP) masyarakat terhadap air bersih dan mengidentifikasi faktor-faktor yang mempengaruhinya. Penelitian ini menggunakan analisis deskriptif, analisis Willingness to Pay dengan menggunakan dichotomous choice CVM, dan analisis regresi logistik. Hasil WTP diperoleh sebesar Rp 5.400.84 dan Rp 5 167.81 dengan menggunakan perhitungan metode logit dan Rp 6 000 dengan metode Turnbull. Faktor-faktor yang berpengaruh signifikan terhadap keputusan untuk membayar adalah nilai bid/lelang dan pendapatan. Nilai WTP yang didapatkan menggambarkan WTP masyarakat untuk menerima perubahan sumber air dari non PDAM ke PDAM. Mekanisme pembayaran WTP merupakan tarif air per meter kubik. Nilai air ini adalah untuk kebutuhan air rumah tangga, tidak hanya use value seperti untuk konsumsi dan pemakaian kebutuhan rumah tangga lainnya, tetapi juga merupakan non use value dari air dimana terdapat nilai kenyamanan, nilai kesehatan, nilai keberadaan, dan nilai konservasi.
Keyword: Dichotomous Choice CVM, Sumberdaya Air, Willingness to Pay.

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