40,024 research outputs found
Automatic generation of simplified weakest preconditions for integrity constraint verification
Given a constraint assumed to hold on a database and an update to
be performed on , we address the following question: will still hold
after is performed? When is a relational database, we define a
confluent terminating rewriting system which, starting from and ,
automatically derives a simplified weakest precondition such that,
whenever satisfies , then the updated database will satisfy
, and moreover is simplified in the sense that its computation
depends only upon the instances of that may be modified by the update. We
then extend the definition of a simplified to the case of deductive
databases; we prove it using fixpoint induction
Design of ternary signals for MIMO identification in the presence of noise and nonlinear distortion
A new approach to designing sets of ternary periodic signals with different periods for multi-input multi-output system identification is described. The signals are pseudo-random signals with uniform nonzero harmonics, generated from Galois field GF(q), where q is a prime or a power of a prime. The signals are designed to be uncorrelated, so that effects of different inputs can be easily decoupled. However, correlated harmonics can be included if necessary, for applications in the identification of ill-conditioned processes. A design table is given for q les 31. An example is presented for the design of five uncorrelated signals with a common period N = 168 . Three of these signals are applied to identify the transfer function matrix as well as the singular values of a simulated distillation column. Results obtained are compared with those achieved using two alternative methods
The Cultural Reconstruction of Taboo Under Mama Uluk’s Leadership in Kampong Dukuh, a Sundanese Traditional Hamlet in Garut Regency West Java Indonesia
 Kampung Dukuh yang terletak di Desa Ciroyom, Kecamatan Cikelet Kabupaten Garut merupa- kan salah satu kampung adat yang ada di Jawa Barat yang memiliki banyak keunikan. Pamali sebagai salah satu sistem pengetahuan masyarakat adat Sunda. Pamali masih dipertahankan dalam kebu- dayaan masyarakat adat Kampung Dukuh. Walaupun tidak ada resiko yang tertulis ketika melaku- kan hal yang melanggar pamali, namun masyarakat kampung adat masih merasa takut durhaka atau dosa jika pamali tidak dilaksanakan dalam keseharian hidupnya. Sekaitan dengan hal ini, penelitian ini bertujuan menggambarkan berbagai larangan atau pamali yang telah direkonstruksi di masa kepemimpinan Mama Uluk di kampung Adat Dukuh Kabupaten Garut. Penelitian ini mengguna- kan metode kualitatif dengan teknik pengumpulan data wawancara dan pengamatan langsung. Hasil penelitian ini menjelaskan cara penyampaian larangan pada waktu yang telah ditentukan dan jenis larangan atau pamali atau pamali yang dipelihara dan terus diwariskankan secara turun temurun sampai saat ini dalam kehidupan sehari-hari seperti larangan di Makom Syech Jalil, Hutan Lindung dan bagaimana ketua adat (mama uluk) dalam kepemimpinannya merekonstruksi budaya tersebut dalam kehidupan keseharian mereka di kampung Dukuh kabupaten Garut.
On the variational interpretation of the discrete KP equation
We study the variational structure of the discrete Kadomtsev-Petviashvili
(dKP) equation by means of its pluri-Lagrangian formulation. We consider the
dKP equation and its variational formulation on the cubic lattice as well as on the root lattice . We prove that, on a lattice
of dimension at least four, the corresponding Euler-Lagrange equations are
equivalent to the dKP equation.Comment: 24 page
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