Articoli di riviste: "Projective code"

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Abdulkareem Al-Zangana, Emad Bakr. "Projective MDS Codes Over GF(27)‎". Baghdad Science Journal 18, n. 2(Suppl.) (20 giugno 2021): 1125. http://dx.doi.org/10.21123/bsj.2021.18.2(suppl.).1125.

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MDS code is a linear code that achieves equality in the Singleton bound, and projective MDS (PG-MDS) is MDS code with independents property of any two columns of its generator matrix. In this paper, elementary methods for modifying a PG-MDS code of dimensions 2, 3, as extending and lengthening, in order to find new incomplete PG-MDS codes have been used over . Also, two complete PG-MDS codes over of length and 28 have been found.

2

Limbupasiriporn, J., L. Storme e P. Vandendriessche. "Large weight code words in projective space codes". Linear Algebra and its Applications 437, n. 3 (agosto 2012): 809–16. http://dx.doi.org/10.1016/j.laa.2012.03.024.

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González Sarabia, Manuel, Carlos Rentería Márquez e Eliseo Sarmiento Rosales. "Projective parameterized linear codes". Analele Universitatii "Ovidius" Constanta - Seria Matematica 23, n. 2 (1 giugno 2015): 223–40. http://dx.doi.org/10.1515/auom-2015-0039.

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Abstract In this paper we estimate the main parameters of some evaluation codes which are known as projective parameterized codes. We find the length of these codes and we give a formula for the dimension in terms of the Hilbert function associated to two ideals, one of them being the vanishing ideal of the projective torus. Also we find an upper bound for the minimum distance and, in some cases, we give some lower bounds for the regularity index and the minimum distance. These lower bounds work in several cases, particularly for any projective parameterized code associated to the incidence matrix of uniform clutters and then they work in the case of graphs.

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Kurz, Sascha. "Non-Projective Two-Weight Codes". Entropy 26, n. 4 (27 marzo 2024): 289. http://dx.doi.org/10.3390/e26040289.

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It has been known since the 1970’s that the difference of the non-zero weights of a projective Fq-linear two-weight code has to be a power of the characteristic of the underlying field. Here, we study non-projective two-weight codes and, e.g., show the same result under mild extra conditions. For small dimensions we give exhaustive enumerations of the feasible parameters in the binary case.

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Xie, Wenjiao, e Huisheng Zhang. "Patterned Reed–Muller Sequences with Outer A-Channel Codes and Projective Decoding for Slot-Controlled Unsourced Random Access". Sensors 23, n. 11 (31 maggio 2023): 5239. http://dx.doi.org/10.3390/s23115239.

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We propose a novel slot-pattern-control based coded compressed sensing for unsourced random access with an outer A-channel code capable of correcting t errors. Specifically, an RM extension code called patterned Reed–Muller (PRM) code is proposed. We demonstrate the high spectral efficiency due to its enormous sequence space and prove the geometry property in the complex domain that enhances the reliability and efficiency of detection. Accordingly, a projective decoder based on its geometry theorem is also proposed. Next, the “patterned” property of the PRM code, which partitions the binary vector space into several subspaces, is further extended as the primary principle for designing a slot control criterion that reduces the number of simultaneous transmissions in each slot. The factors affecting the chance of sequence collisions are identified. Finally, the proposed scheme is implemented in two practical outer A-channel codes: (i) the t-tree code and (ii) the Reed–Solomon code with Guruswami–Sudan list decoding, and the optimal setups are determined to minimize SNR by optimizing the inner and outer codes jointly. In comparison with the existing counterpart, our simulation results confirm that the proposed scheme compares favorably with benchmark schemes regarding the energy-per-bit requirement to meet a target error probability as well as the number of accommodated active users in the system.

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González-Sarabia, Manuel, Delio Jaramillo e Rafael H. Villarreal. "On the generalized Hamming weights of certain Reed–Muller-type codes". Analele Universitatii "Ovidius" Constanta - Seria Matematica 28, n. 1 (1 marzo 2020): 205–17. http://dx.doi.org/10.2478/auom-2020-0014.

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AbstractThere is a nice combinatorial formula of P. Beelen and M. Datta for the r-th generalized Hamming weight of an a ne cartesian code. Using this combinatorial formula we give an easy to evaluate formula to compute the r-th generalized Hamming weight for a family of a ne cartesian codes. If 𝕏 is a set of projective points over a finite field we determine the basic parameters and the generalized Hamming weights of the Veronese type codes on 𝕏 and their dual codes in terms of the basic parameters and the generalized Hamming weights of the corresponding projective Reed–Muller-type codes on 𝕏 and their dual codes.

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Zubov, A. U. "Authentication code with secrecy based on projective geometry". Prikladnaya diskretnaya matematika, n. 20 (1 giugno 2013): 39–49. http://dx.doi.org/10.17223/20710410/20/5.

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XU, Xiaofan. "On Deep Holes of Projective Reed-Solomon Codes over Finite Fields with Even Characteristic". Wuhan University Journal of Natural Sciences 28, n. 1 (febbraio 2023): 15–19. http://dx.doi.org/10.1051/wujns/2023281015.

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Projective Reed-Solomon code is an important class of maximal distance separable codes in reliable communication and deep holes play important roles in its decoding. In this paper, we obtain two classes of deep holes of projective Reed-Solomon codes over finite fields with even characteristic. That is, let [see formula in PDF] be finite field with even characteristic, [see formula in PDF], and let [see formula in PDF] be the Lagrange interpolation polynomial of the first [see formula in PDF] components of the received vector [see formula in PDF]. Suppose that the [see formula in PDF]-th component of [see formula in PDF] is 0, and [see formula in PDF],[see formula in PDF] where [see formula in PDF], and [see formula in PDF] is a polynomial over [see formula in PDF] with degree no more than [see formula in PDF]. Then the received vector [see formula in PDF] is a deep hole of projective Reed-Solomon codes [see formula in PDF]. In fact, our result partially solved an open problem on deep holes of projective Reed-Solomon codes proposed by Wan in 2020.

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Fareeq Fendi, Dunya, e Nada Yassen Kasm Yahya. "Construction of q-ary(n,M,d)-codes in PG(2,16)". Wasit Journal of Pure sciences 2, n. 1 (26 marzo 2023): 111–30. http://dx.doi.org/10.31185/wjps.110.

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The goal of this paper was to study the applications of the projective plane PG (2, q) over a Galois field of order q in the projective q-ary (n, M, d) -code such that the parameters length of code n, the maximum value size code M, and the minimum distance d with the error-correcting e according to an incidence matrix have been calculated. Also, this research provides examples and theorems of links between the combinatorial structures and coding theory. The method of the research depends on the classification of the points and lines in PG (2, q).

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Ibrahim, Dr Mohammed, e Islam. "Large (k,3)-arcs in PG(2,19) and the related linear codes". Journal of Kufa for Mathematics and Computer 11, n. 1 (30 marzo 2024): 43–54. http://dx.doi.org/10.31642/jokmc/2018/110108.

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A (n,r)-arc in a projective plane PG(2,q) is a set of n points such that some r, but no r+1 of them, are collinear. A (n,r)-arc is called complete if it is not contain in a (n+1,r)-arc. A linear -code over a finite field is a k-dimensional subspace of with minimum hamming distance d and length n. A code with parameters with Griesmer bound , is called Griesmer code. The major aim of this research is to find large size for the complete (k,3)-arcs in the projective plane of order nineteen PG(2,19) using the method of secants distributions, and the disjoint union of arcs, as well as, adding and removing points to (from) particular conic respectively. Also, we find the Griesmer codes that correspond to each large complete (k,3)-arcs, k=29,30,31. We introduced 20 inequivalent (29,3)-arcs up to secant distribution, 10 of them are complete. Also, we introduced 8 inequivalent (30,3)-arcs up to secant distribution, 2 of them are complete. Moreover, we construct 3 inequivalent complete (31,3)-arcs up to secant distribution, and then find the corresponding linear codes to some of the (29,3)-arcs, (30,3)-arcs and (31,3)-arcs. In particular, we established 3 types of Griesmer codes, and we find the weight enumerator that correspond to each one of them.

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Bright, Curtis, Kevin K. H. Cheung, Brett Stevens, Ilias Kotsireas e Vijay Ganesh. "A SAT-based Resolution of Lam's Problem". Proceedings of the AAAI Conference on Artificial Intelligence 35, n. 5 (18 maggio 2021): 3669–76. http://dx.doi.org/10.1609/aaai.v35i5.16483.

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In 1989, computer searches by Lam, Thiel, and Swiercz experimentally resolved Lam's problem from projective geometry—the long-standing problem of determining if a projective plane of order ten exists. Both the original search and an independent verification in 2011 discovered no such projective plane. However, these searches were each performed using highly specialized custom-written code and did not produce nonexistence certificates. In this paper, we resolve Lam's problem by translating the problem into Boolean logic and use satisfiability (SAT) solvers to produce nonexistence certificates that can be verified by a third party. Our work uncovered consistency issues in both previous searches—highlighting the difficulty of relying on special-purpose search code for nonexistence results.

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López, Hiram, Eliseo Sarmiento, Maria Pinto e Rafael Villarreal. "Parameterized affine codes". Studia Scientiarum Mathematicarum Hungarica 49, n. 3 (1 settembre 2012): 406–18. http://dx.doi.org/10.1556/sscmath.49.2012.3.1216.

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Let K be a finite field and let X* be an affine algebraic toric set parameterized by monomials. We give an algebraic method, using Gröbner bases, to compute the length and the dimension of CX* (d), the parameterized affine code of degree d on the set X*. If Y is the projective closure of X*, it is shown that CX* (d) has the same basic parameters that CY (d), the parameterized projective code on the set Y. If X* is an affine torus, we compute the basic parameters of CX* (d). We show how to compute the vanishing ideals of X* and Y.

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AL-Seraji, Najm A. M., e Hamza L. M. Ajaj. "Some Applications of Coding Theory in the Projective Plane of Order Four". Al-Mustansiriyah Journal of Science 30, n. 1 (15 agosto 2019): 152. http://dx.doi.org/10.23851/mjs.v30i1.544.

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The main aim of this research is to introduce the relationship between the topic of coding theory and the projective plane of order four. The maximum value of size code M over the finite field of order four and an incidence matrix with the parameters, n (length of code), d (minimum distance of code) and e (error-correcting of code) have been constructed. Some examples and theorems have been given.

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Dunya Fareeq Fendi. "Construction of Qــ Ary(n,Μ,d )ــ Codes in PG (2,9)". Journal of Electrical Systems 20, n. 6s (2 maggio 2024): 2550–60. http://dx.doi.org/10.52783/jes.3242.

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This study's main objective is to offer the connection between the projective plane of order nine & the field of coding theory. An incidence matrix has been developed using the parameters n (code length), d (code min. distance), and e (code error correcting). The greatest value of size code M across a limited field of the ninth order has also been determined. There are a few theorems and examples provided.

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Al-Seraji, Najm Abdul Zahraa, e Nagham Satar Mohammed Al-Badrial. "Partitions by subgeometries of projective plane over a galois field of order 3n, n = 1, 2, 3". Journal of Wasit for Science and Medicine 8, n. 3 (9 dicembre 2022): 150–64. http://dx.doi.org/10.31185/jwsm.282.

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The purpose of this thesis is to split the projective plane of PG (2,9) into seven disjoint projective subplanes PG (2,3) and thirteen disjoint complete arcs of degree two and size seven. The projective line of order twenty-seven PG (1,27) has been partitioned into seven disjoint projective sublines PG (1,3) and the number of inequivalent -sets which are unordered sets of four points is classified. The group action on projective lines PG (1,3n) and projective PG (1,3n), n = 1, 2, 3 planes is explained and we have introduced theorems and examples and the subspaces of PG (1,3n) and PG (2,3n), n = 1, 2, 3 are shown. Each of these partitions gives rise to an error-correcting code that corrects the maximum possible number of errors for its length. GAP-Groups–Algorithms, Programming a system for computational discrete algebra has been applied.

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Yahya, Hanan Maysar Sabih, e Nada Yassen Kasm Yahya. "Lower bound for m_r (2,41) and related code". BIO Web of Conferences 97 (2024): 00159. http://dx.doi.org/10.1051/bioconf/20249700159.

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A (k, n) - arc is a set of k points of a projective plane such that some n, but no n+1 of them, are collinear. The maximum size of a (k, n) - arc in PG(2 q) is denoted by mr(2, q). In this paper we found mr(2,41) for n = (2,3 ,...,40) ,In this work, we construct a complete (k, n)-arcs in the projective space over Galois field GF(41), we construct the complete(k,n+1)-arcs from the complete (k, n)-arcs, where 2 ≤ n ≤ 42 , by using computer program we added some points of index zero, and found all the complete (k, n)-arcs in PG(2,41) and [k,n,d]_code.

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Kurz, Sascha. "No Projective 16-Divisible Binary Linear Code of Length 131 Exists". IEEE Communications Letters 25, n. 1 (gennaio 2021): 38–40. http://dx.doi.org/10.1109/lcomm.2020.3021939.

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Dey, Partha Pratim, e M. Asifuzzaman. "A note on the code of projective plane of order four". Journal of Discrete Mathematical Sciences and Cryptography 11, n. 6 (dicembre 2008): 621–37. http://dx.doi.org/10.1080/09720529.2008.10698395.

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Argon, Cenk, e H. Farooq Ahmad. "Optimal optical orthogonal code design using difference sets and projective geometry". Optics Communications 118, n. 5-6 (agosto 1995): 505–8. http://dx.doi.org/10.1016/0030-4018(95)00246-5.

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Al-Seraji, Najm A., e Riyam A. Al-Ogali. "Classification of Arcs in Finite Projective Plane of Order Sixteen". Al-Mustansiriyah Journal of Science 29, n. 1 (31 ottobre 2018): 138. http://dx.doi.org/10.23851/mjs.v29i1.184.

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The aim of the paper is to classify certain geometric structures, called arcs. The main computing tool is the mathematical programming language GAP. In the plane PG(2,16),the important arcs are called complete and are those that cannot be increased to a larger arc. So far, all arcs up to size eighteen have been classified. Each of these arcs gives rise to an error-correcting code that corrects the maximum possible number of errors for its length.

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FU, Qiang, Ruihu LI, Luobin GUO e Gang CHEN. "Singleton-Type Optimal LRCs with Minimum Distance 3 and 4 from Projective Code". IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E104.A, n. 1 (1 gennaio 2021): 319–23. http://dx.doi.org/10.1587/transfun.2019eal2158.

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Coghetto, Roland. "Duality Notions in Real Projective Plane". Formalized Mathematics 29, n. 4 (1 dicembre 2021): 161–73. http://dx.doi.org/10.2478/forma-2021-0016.

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Summary In this article, we check with the Mizar system [1], [2], the converse of Desargues’ theorem and the converse of Pappus’ theorem of the real projective plane. It is well known that in the projective plane, the notions of points and lines are dual [11], [9], [15], [8]. Some results (analytical, synthetic, combinatorial) of projective geometry are already present in some libraries Lean/Hott [5], Isabelle/Hol [3], Coq [13], [14], [4], Agda [6], . . . . Proofs of dual statements by proof assistants have already been proposed, using an axiomatic method (for example see in [13] - the section on duality: “[...] For every theorem we prove, we can easily derive its dual using our function swap [...]2”). In our formalisation, we use an analytical rather than a synthetic approach using the definitions of Leończuk and Prażmowski of the projective plane [12]. Our motivation is to show that it is possible by developing dual definitions to find proofs of dual theorems in a few lines of code. In the first part, rather technical, we introduce definitions that allow us to construct the duality between the points of the real projective plane and the lines associated to this projective plane. In the second part, we give a natural definition of line concurrency and prove that this definition is dual to the definition of alignment. Finally, we apply these results to find, in a few lines, the dual properties and theorems of those defined in the article [12] (transitive, Vebleian, at_least_3rank, Fanoian, Desarguesian, 2-dimensional). We hope that this methodology will allow us to continued more quickly the proof started in [7] that the Beltrami-Klein plane is a model satisfying the axioms of the hyperbolic plane (in the sense of Tarski geometry [10]).

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Hayder, Hajir Hayder, Nada Yassen Kasm e Noor Hussain Abdullah. "Application of Coding Theory in Field 5". Al-Kitab Journal for Pure Sciences 8, n. 01 (31 maggio 2024): 136–44. http://dx.doi.org/10.32441/kjps.08.01.p12.

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The main aim of this paper introduce the relationship between the topic of coding theory and the projective plane of order five where special points were found in field 5, which is 31 points, in addition to 31 straight lines, and by applying the theorem that gives the number 1 for the point that lies on the straight line and the number 0 for the point that does not lie on the straight line, we get the code n = 31, d = 6, e = 2, from which we get the table m, v, n. ,n,h, and based on these tables, the distance difference between the code elements was found, where the minimum distance was 6 and the largest distance was 31. These values were used to test the optimality of the code. We can generalize this theorem and apply it to larger fields such as 21 or 23 and others, test their ideality, and find the difference between field 5 and the rest of the fields. M is the maximum value of the size of code over the finite field of order five and an incidence matrix with the parameters, n (length of code), d(minimum distance of code ), and e (error-correcting of code)have been constructed some example and theorem have been given.

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Sokolov, B. G. "Код как деменция памяти и решимости быть". Studia Culturae, n. 52 (10 gennaio 2023): 61. http://dx.doi.org/10.31312/2310-1245-2022-52-61-73.

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In modern scientific and political discourse, the concept of code has become quite widespread, as an explanatory matrix and as a possible structure of reality. At the same time, the concept of code itself is not a scientifically based scientific concept. It is worth mentioning that until the twentieth century, the concept of code was not used at all either in the humanities or in natural science discourse, or had a rather narrow application, closing in on the concept of a cipher. It was only in the twentieth century that this concept began to be used. The most famous modern thinkers who have used this concept are R. Barthes and J. Baudrillard. In the works of R. Barthes, the concept of code is used in the analysis of a literary text and acts as a kind of “substitute” for the figure of the author. It is the code structure of the text that allows us to talk about the so-called death of the author. In the works of J. Baudrillard's phenomenon of the code refers to the neo-capitalist reality and is subject to critical reflection. The author of the article follows a critical view of the ZH code. Baudrillard considers the modern scientific “fashion” for the use of the conceptual resource of the code as a definite symptom of the modern post-industrial society, in which, by reducing to code unity, the active projective assembly of a person, his memory, is eliminated.

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Lam, C. W. H., L. Thiel e S. Swiercz. "The nonexistence of code words of weight 16 in a projective plane of order 10". Journal of Combinatorial Theory, Series A 42, n. 2 (luglio 1986): 207–14. http://dx.doi.org/10.1016/0097-3165(86)90091-9.

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Márton, Áron, e János K. Asbóth. "Coherent errors and readout errors in the surface code". Quantum 7 (21 settembre 2023): 1116. http://dx.doi.org/10.22331/q-2023-09-21-1116.

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We consider the combined effect of readout errors and coherent errors, i.e., deterministic phase rotations, on the surface code. We use a recently developed numerical approach, via a mapping of the physical qubits to Majorana fermions. We show how to use this approach in the presence of readout errors, treated on the phenomenological level: perfect projective measurements with potentially incorrectly recorded outcomes, and multiple repeated measurement rounds. We find a threshold for this combination of errors, with an error rate close to the threshold of the corresponding incoherent error channel (random Pauli-Z and readout errors). The value of the threshold error rate, using the worst case fidelity as the measure of logical errors, is 2.6%. Below the threshold, scaling up the code leads to the rapid loss of coherence in the logical-level errors, but error rates that are greater than those of the corresponding incoherent error channel. We also vary the coherent and readout error rates independently, and find that the surface code is more sensitive to coherent errors than to readout errors. Our work extends the recent results on coherent errors with perfect readout to the experimentally more realistic situation where readout errors also occur.

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Ibrahim, Shaymaa Haleem, e Nada Yassen Kasm. "The Possibility of Applying Rumen Research at the Projective Plane PG (2,17)". Modern Applied Science 13, n. 8 (29 luglio 2019): 150. http://dx.doi.org/10.5539/mas.v13n8p150.

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One of the main objectives of this research is to use a new theoretical method to find arcs and Blocking sets. This method includes the deletion of a set of points from some lines under certain conditions explained in a paragraph 2.In this paper we were able to improve the minimum constraint of the (256,16) – arc in the projection plane PG(2,17).Thus , we obtained a new {50,2}-blocking set for size Less than 3q , and according to the theorem (1.3.1),we obtained the linear 257,3,24117    code, theorem( 2.1.1 ) giving some examples on arcs of the Galois field GF(q);q=17."

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KOGA, Hiroki, e Yusuke MINAMI. "A Digital Fingerprinting Code Based on a Projective Plane and Its Identifiability of All Malicious Users". IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E94-A, n. 1 (2011): 223–32. http://dx.doi.org/10.1587/transfun.e94.a.223.

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Fang, Jian Wen, Jin Hui Yu, Shuang Xia Han e Peng Wang. "Real-Time Ocean Water Animation in Cartoon Style". Key Engineering Materials 474-476 (aprile 2011): 2320–24. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.2320.

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This paper presents a model for automatically generating 3D cartoon ocean water animations in real-time. The dynamic ocean water surface model is modeled by a spectral method. The cartoon rendering process is implemented by multipass on GPU: First, we code normal of ocean model and generate normal map. Next, we extract discontinuities from normal map and smooth it into edge map. Finally we combine the edge map with cartoon shading based on a projective texture mapping. Some experimental results demonstrate the prettiness and efficiency of the presented model.

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Gallichan, Deanna J., e Carol George. "Assessing attachment status in adults with intellectual disabilities: the potential of the Adult Attachment Projective Picture System". Advances in Mental Health and Intellectual Disabilities 8, n. 2 (3 marzo 2014): 103–19. http://dx.doi.org/10.1108/amhid-10-2012-0004.

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Purpose – The purpose of this paper is to explore the potential of the Adult Attachment Projective Picture System (AAP) as a measure of attachment state of mind in adults with intellectual disabilities. The AAP is a free response picture system method of assessing patterns of adult attachment with established validity and reliability in community and clinical samples. Design/methodology/approach – The paper reports on five cases of adults with intellectual disabilities who were administered the AAP as part of routine clinical work. The AAP administration procedure was modified to take account of the participants’ intellectual disabilities. Findings – It was possible to code and classify each AAP using the established coding and classification system. The authors coded four cases blind to each other ' s classification; they agreed on classifications for three cases and reached consensus on the fourth. The AAP analysis showed strong correspondence with case history material. Originality/value – The AAP demonstrates the potential to assess attachment state of mind in adults with intellectual disabilities and is the first developmental measure of attachment status that has shown potential in this population. The paper discusses clinical application of the AAP and directions for future research.

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Rodrigues, B. G. "A Projective Two-Weight Code Related to the Simple Group $$\mathrm{Co}_1$$ Co 1 of Conway". Graphs and Combinatorics 34, n. 3 (4 aprile 2018): 509–21. http://dx.doi.org/10.1007/s00373-018-1890-z.

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Strähle, Jochen, e Franziska Girwert. "Impact of a Fashion fTRACE App on the Perception of Sustainability". Journal Of International Business Research And Marketing 1, n. 2 (2015): 7–18. http://dx.doi.org/10.18775/jibrm.1849-8558.2015.12.3001.

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The purpose of this paper is to examine the relationship between the consumers’ perception of sustainability and the application of a QR-code in stores with the focus on the information searching behavior regarding sustainable aspects. An online questionnaire was conducted with fashion students at Reutlingen University: in total, 65 students participated in the survey. Paired samples t-test and other statistical analyses were applied to test research questions. Apart from this, the research paper is based on a literature review. Furthermore, the decision was taken to use a projective method in the form of a dummy fashion fTRACE website. Key findings of the survey are that participants give sustainable aspects a higher importance with a QR-code than without one. Participants who prefer a product with detailed information experience a “positive shopping feeling” when provided with transparency via a QR-code. “Origin”, “production” and “quality” were rated of higher importance by those participants. These findings suggest that, transparency provided through the application of a QR-Code in stores influences the consumers’ perception of sustainability. Due to the small sample size of participants (65) in the study, findings of this research not generalizable to a larger population. This paper focused on the consumers’ information searching behavior regarding sustainable aspects, limiting its findings to impacts on perception of sustainability. Further research is therefore recommended.

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Sang, Xiahan, Adedapo A. Oni e James M. LeBeau. "Atom Column Indexing: Atomic Resolution Image Analysis Through a Matrix Representation". Microscopy and Microanalysis 20, n. 6 (17 novembre 2014): 1764–71. http://dx.doi.org/10.1017/s1431927614013506.

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AbstractHere, we report the development of an approach to map atomic resolution images into a convenient matrix representation. Through the combination of two-dimensional Gaussian fitting and the projective standard deviation, atom column locations are projected onto two noncollinear reference lattice vectors that are used to assign each a unique (i, j) matrix index. By doing so, straightforward atomic resolution image analysis becomes possible. Using practical examples, we demonstrate that the matrix representation greatly simplifies categorizing atom columns to different sublattices. This enables a myriad of direct analyses, such as mapping atom column properties and correlating long-range atom column pairs. MATLAB source code can be downloaded from https://github.com/subangstrom/aci.

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Ashabrawy, M. A., e E. E. Elbehadi. "3-D from 2-D Using Warping Transformations ." INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY 13, n. 4 (30 aprile 2014): 4430–55. http://dx.doi.org/10.24297/ijct.v13i4.2869.

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Shown in this paper are methods on how to find the third dimension of a single image or from the two views of the image taking in a different angle using the method more accurate and faster to get to the third dimension in the following cases: One image of the same scene. Two views of the same scene from two different perspectives. Pictures of parts of the same scene. Set of pictures for different views of the work of the subject Panorama. This method is known Image Warping, which falls below a set of transfers such as (Affine - Bilinear - Projective - Mosaic â€“ Similarity transformation) was compared to the work of transfers between the previous and this will be applied to more pictures. The idea is based on building code software is built on the programming language Visual C + + with the library for drawing an OpenGL program Matlab, which way can build a model of the following conversions, which fall under the so-called image warping of the conversion linear Bilinear Mapping and conversion Affine Mapping and conversion imagery Projective Mapping . shown in this paper are methods on how to correct camera exposure changes and how to blend the stitching line between the images. We will show panorama photos generated from both still image.

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Bartoli, Daniele, Antonio Cossidente, Giuseppe Marino e Francesco Pavese. "On cutting blocking sets and their codes". Forum Mathematicum 34, n. 2 (6 gennaio 2022): 347–68. http://dx.doi.org/10.1515/forum-2020-0338.

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Abstract Let PG ⁡ ( r , q ) {\operatorname{PG}(r,q)} be the r-dimensional projective space over the finite field GF ⁡ ( q ) {\operatorname{GF}(q)} . A set 𝒳 {\mathcal{X}} of points of PG ⁡ ( r , q ) {\operatorname{PG}(r,q)} is a cutting blocking set if for each hyperplane Π of PG ⁡ ( r , q ) {\operatorname{PG}(r,q)} the set Π ∩ 𝒳 {\Pi\cap\mathcal{X}} spans Π. Cutting blocking sets give rise to saturating sets and minimal linear codes, and those having size as small as possible are of particular interest. We observe that from a cutting blocking set obtained in [20], by using a set of pairwise disjoint lines, there arises a minimal linear code whose length grows linearly with respect to its dimension. We also provide two distinct constructions: a cutting blocking set of PG ⁡ ( 3 , q 3 ) {\operatorname{PG}(3,q^{3})} of size 3 ⁢ ( q + 1 ) ⁢ ( q 2 + 1 ) {3(q+1)(q^{2}+1)} as a union of three pairwise disjoint q-order subgeometries, and a cutting blocking set of PG ⁡ ( 5 , q ) {\operatorname{PG}(5,q)} of size 7 ⁢ ( q + 1 ) {7(q+1)} from seven lines of a Desarguesian line spread of PG ⁡ ( 5 , q ) {\operatorname{PG}(5,q)} . In both cases, the cutting blocking sets obtained are smaller than the known ones. As a byproduct, we further improve on the upper bound of the smallest size of certain saturating sets and on the minimum length of a minimal q-ary linear code having dimension 4 and 6.

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T Shathish Kumar. "Rand-Index Target Projective Gradient Deep Belief Network for Software Fault Prediction". Journal of Electrical Systems 20, n. 6s (2 maggio 2024): 2656–70. http://dx.doi.org/10.52783/jes.3276.

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Predicting defective software modules before testing is a valuable operation that reduces time and cost of software testing. Source code fault prediction plays a vital role in improving software quality that effectively assists in optimization testing resource allocation. Several machine learning and ensemble learning techniques has been extensively evolved over the recent few years to predict defect at an early stage. These techniques made predictions based on historical defect data, the software metrics. Nevertheless, the time efficient and accurate fault predictions are the major challenging tasks that yet have to be addressed. In order to ensure accurate software fault prediction, a method called Rand-Index Target Projective Gradient Deep Belief Network (RTPGDBN) is designed. The proposed RTPGDBN method comprises of three processes namely acquiring JAVA packages, software metric selection and classification. First, the number of JAVA packages is used as input from the dataset. Second with the JAVA packages obtained as input, Rand similarity indexive target projection function is applied for selecting the most significant software metrics in order to minimize time complexity of fault prediction. Third, with the selected metrics, classification is performed using Tversky Gradient Deep Belief neural network. Also, gradient descent function is applied to minimize classification error, therefore ensuring accurate software fault classification results obtained at the output layer. Experimental setup of proposed RPGDDBN and existing methods are implemented in Java language and the dataset collected from smell prediction replication package. Performance analysis is carried out with different quantitative metrics such as accuracy, precision, recall, F-measure, and time complexity and space complexity. Through extensive experiments on repository data, experimental results indicate that our RPGDDBN method outperforms two state-of-the-art defect detection methods in terms of different performance metrics.

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Key, Jennifer D., e Fidele F. Ngwane. "A lower bound for the minimum weight of the dual 7-ary code of a projective plane of order 49". Designs, Codes and Cryptography 44, n. 1-3 (24 maggio 2007): 133–42. http://dx.doi.org/10.1007/s10623-007-9072-7.

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Page, Robert, Ruriko Yoshida e Leon Zhang. "Tropical principal component analysis on the space of phylogenetic trees". Bioinformatics 36, n. 17 (9 giugno 2020): 4590–98. http://dx.doi.org/10.1093/bioinformatics/btaa564.

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Abstract Motivation Due to new technology for efficiently generating genome data, machine learning methods are urgently needed to analyze large sets of gene trees over the space of phylogenetic trees. However, the space of phylogenetic trees is not Euclidean, so ordinary machine learning methods cannot be directly applied. In 2019, Yoshida et al. introduced the notion of tropical principal component analysis (PCA), a statistical method for visualization and dimensionality reduction using a tropical polytope with a fixed number of vertices that minimizes the sum of tropical distances between each data point and its tropical projection. However, their work focused on the tropical projective space rather than the space of phylogenetic trees. We focus here on tropical PCA for dimension reduction and visualization over the space of phylogenetic trees. Results Our main results are 2-fold: (i) theoretical interpretations of the tropical principal components over the space of phylogenetic trees, namely, the existence of a tropical cell decomposition into regions of fixed tree topology; and (ii) the development of a stochastic optimization method to estimate tropical PCs over the space of phylogenetic trees using a Markov Chain Monte Carlo approach. This method performs well with simulation studies, and it is applied to three empirical datasets: Apicomplexa and African coelacanth genomes as well as sequences of hemagglutinin for influenza from New York. Availability and implementation Dataset: http://polytopes.net/Data.tar.gz. Code: http://polytopes.net/tropica_MCMC_codes.tar.gz. Supplementary information Supplementary data are available at Bioinformatics online.

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Luo, Qiao, e Xiaobing Zhang. "Numerical simulation of serial launch process of multiple projectiles considering the aftereffect period". International Journal of Numerical Methods for Heat & Fluid Flow 27, n. 8 (7 agosto 2017): 1720–34. http://dx.doi.org/10.1108/hff-04-2016-0151.

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Purpose The numerical simulation of the serial launch process of multiple projectiles is an important engineering problem. However, the projectiles’ motion law is hard to obtain completely only by interior ballistic model. The muzzle flow field affects the projectiles’ velocities when the projectiles pass through it. Also, the propellant gas from previous projectiles may decelerate the later projectiles. Therefore, the aftereffect period should be simulated together with the interior ballistic process of multiple projectiles when researching the serial launch process for accurate motion law of the projectiles. Design/methodology/approach The computational fluid dynamics (CFD) software is used to simulate the muzzle flow field. A one-dimensional two-phase reaction flow model is implemented in a computational code for the numerical simulation of gas-solid two-phase reaction flow, during the serial launch process. The computational code is coupled with CFD software by a user-defined function. Findings Compared with the first projectile, the formation process of the shock bottle of the second projectile is different. After the projectile head flies out of the muzzle, the projectile head pressure decreases rapidly, but then, it is not always equal to 0.1 MPa. After the projectiles leave the muzzle, the velocity increments of each projectile are mainly determined by muzzle pressure. Originality/value This paper presents a prediction tool to understand the projectiles’ motion law during the serial launch process of the multiple projectiles considering aftereffect period, and can be used as a research tool for future ballistic studies of a serial launch system of multiple projectiles.

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Hrytsenko, O. S. "Analysis of the criteria of originality in projective methods in the study of talented and gifted individuals". Fundamental and applied researches in practice of leading scientific schools 41, n. 5 (30 novembre 2020): 63–68. http://dx.doi.org/10.33531/farplss.2020.5.11.

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Analysis of the criteria of originality in projective methods in the study of talented and gifted individuals. The study analyses the criterion of originality in projective diagnostic tests used for the assessment of creative and gifted persons. For the analysis, the tests of Torrance, Gilford, Wartegg, and the methodology of "Pictogram" were utilized. The concept of originality is assessed in all these projective methods. This concept, according to J. Gilford, is strongly related to the creativity of a person. The originality, according to the scientist, is the capability to find the non-standard solutions, which are different from most answers for the particular test task. Thus, this parameter is related to the capability to create the new ideas based on the standard stimuli, which is the basis of creativity. However, the true originality, as the ability to produce a new product, cannot be measured within the testing procedure. Thus, J. Gilford created the criterion of originality of projective tests as a statistical parameter. For different tests, the frequency of the solution, needed for describing it as original, can be different. Precisely, in Torrance’s test, the answer is considered original if it occurs in less than 5% of answers. In Gilford's test, the original solution was shown to be presented in less than then 2.5% cases. For the "Pictogram" methodology, the original answer occurs in less than 2%, and in Wartegg’s test – in less than 1%. When analysing the concept of originality, it is also necessary to ensure the adequacy of the proposed solution is also evaluated. A tested person can propose the answer to the test task that ignores the instruction or the essential characteristics of stimuli. In this case, such a variant of the solution of the problem will be original, as it occurs rarely. However, this solution does not appear to be adequate and it might not be related to the creativity of a person. Hence, original but adequate answers should be applied as indicators of the true creativity. Thus, the criterion of originality is a statistical one. To evaluate the originality of the answer, a researcher assesses the frequency of a particular result in the entire assessed group. This criterion in the significant way depends on the cultural code of the person as well as on the sample of the study. The same solution can be considered as original for one sample and standard, normative for another one. On the other hand, creativity of a person not always can be controlled and applied consciously. The creative process is frequently spontaneous. Therefore, the absence of the original solutions in the results of proactive tests does not necessarily mean the absence of creativity in a particular person. In such a rank, the criterion of originality can serve as an indicator of a non-standard process of thinking of an individual. However, the assessment of creativity and giftedness requires a comprehensive and individual approach.

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Moxley, Rayment E., Mark D. Adley e Bob Rohani. "Impact of Thin-Walled Projectiles with Concrete Targets". Shock and Vibration 2, n. 5 (1995): 355–64. http://dx.doi.org/10.1155/1995/861749.

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An experimental program to determine the response of thin-walled steel projectiles to the impact with concrete targets was recently conducted. The projectiles were fired against 41-MPa concrete targets at an impact velocity of 290 m/s. This article contains an outline of the experimental program, an examination of the results of a typical test, and predictions of projectile deformation by classical shell theory and computational simulation. Classical shell analysis of the projectile indicated that the predicted impact loads would result in circumferential buckling. A computational simulation of a test was conducted with an impact/penetration model created by linking a rigid-body penetration trajectory code with a general-purpose finite element code. Scientific visualization of the resulting data revealed that circumferential buckling was induced by the impact conditions considered.

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Weng, Zhenyu, e Yuesheng Zhu. "Online Hashing with Efficient Updating of Binary Codes". Proceedings of the AAAI Conference on Artificial Intelligence 34, n. 07 (3 aprile 2020): 12354–61. http://dx.doi.org/10.1609/aaai.v34i07.6920.

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Online hashing methods are efficient in learning the hash functions from the streaming data. However, when the hash functions change, the binary codes for the database have to be recomputed to guarantee the retrieval accuracy. Recomputing the binary codes by accumulating the whole database brings a timeliness challenge to the online retrieval process. In this paper, we propose a novel online hashing framework to update the binary codes efficiently without accumulating the whole database. In our framework, the hash functions are fixed and the projection functions are introduced to learn online from the streaming data. Therefore, inefficient updating of the binary codes by accumulating the whole database can be transformed to efficient updating of the binary codes by projecting the binary codes into another binary space. The queries and the binary code database are projected asymmetrically to further improve the retrieval accuracy. The experiments on two multi-label image databases demonstrate the effectiveness and the efficiency of our method for multi-label image retrieval.

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Lysenko, Tatyana Mikhaylovna. "Steppe communities in the vicinity of Togliatti (Samara Region)". Samara Journal of Science 7, n. 4 (30 novembre 2018): 74–80. http://dx.doi.org/10.17816/snv201874113.

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The paper describes the study of steppe vegetation in the Samara Region. It contains results of the steppe communities field study conducted in 2014-2015 in the vicinity of Togliatti (Samara Region). Geobotanical relevs were made on standard sites for steppe vegetation. Projective covering of plant species in field conditions was estimated as a percentage and then converted to scores using B.M. Mirkins scale. The relevs are placed in the geobotanical database Vegetation of the Volga and Ural Basins and processed using the computer program JUICE. Bioindication studies were conducted using the IBIS program. As a result of the syntaxonomic analysis carried out using the floral approach to the classification of vegetation by J. Braun-Blanquet, 2 new associations and 6 new subassociations were identified. Their names are given in accordance with the International Code of Phytosociological Nomenclature. Their position in the system of higher syntaxons of Europe is established, nomenclature types, diagnostic types are given, composition and structure, ecology and distribution of communities are characterized as well as the results of processing according to the scales by L.G. Ramensky. The communities of all established syntaxons are recommended for inclusion in the 2nd edition of the Green Book of the Samara Region.

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Bullinger, S., C. Bodensteiner e M. Arens. "3D SURFACE RECONSTRUCTION FROM MULTI-DATE SATELLITE IMAGES". International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2021 (28 giugno 2021): 313–20. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2021-313-2021.

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Abstract. The reconstruction of accurate three-dimensional environment models is one of the most fundamental goals in the field of photogrammetry. Since satellite images provide suitable properties for obtaining large-scale environment reconstructions, there exist a variety of Stereo Matching based methods to reconstruct point clouds for satellite image pairs. Recently, a Structure from Motion (SfM) based approach has been proposed, which allows to reconstruct point clouds from multiple satellite images. In this work, we propose an extension of this SfM based pipeline that allows us to reconstruct not only point clouds but watertight meshes including texture information. We provide a detailed description of several steps that are mandatory to exploit state-of-the-art mesh reconstruction algorithms in the context of satellite imagery. This includes a decomposition of finite projective camera calibration matrices, a skew correction of corresponding depth maps and input images as well as the recovery of real-world depth maps from reparameterized depth values. The paper presents an extensive quantitative evaluation on multi-date satellite images demonstrating that the proposed pipeline combined with current meshing algorithms outperforms state-of-the-art point cloud reconstruction algorithms in terms of completeness and median error. We make the source code of our pipeline publicly available.

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Panokin, A. M. "Criminal Appellate Proceedings through the Prism of a Social Project: Synergy of the Society’s Request and Legislative Regulation". Lex Russica 77, n. 4 (24 aprile 2024): 65–75. http://dx.doi.org/10.17803/1729-5920.2024.209.4.065-075.

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Public relations, developing in the process of judicial decisions reviewing in criminal cases on appeal, arise on the basis of criminal procedure law rules with great socio-projective potential, which means activities aimed to create specific images of the future and certain details of programs and plans being developed that often result in a new or modernized social object with an original mechanism and unique means of regulation of public relations. The institution of criminal appellate proceedings has been formed in the process of a long evolution, during which many options for reviewing court decisions were tested and rejected. It also acts as an object of social design, which will help ensure the effectiveness of law enforcement and implementation of the objective of criminal proceedings, enshrined in Article 6 of the Code of Criminal Procedure of the Russian Federation. As the result of designing appeal proceedings in criminal cases, a set of scientifically grounded functional proposals can be developed. They can have a positive impact on the review in the court of appeal, since the latter should be able to satisfy the social interest (need) of interested parties, meaning not the satisfaction of the appeal, but the administration of justice in the full sense of the word.

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Cui, Jie, Xin Chen, Ali Tian, Renchuan Ye, Yanxi Qiao e Dongqin Miu. "Investigation of the penetration resistance of monolithic and double-layered steel plates". International Journal of Modern Physics B 33, n. 01n03 (30 gennaio 2019): 1940005. http://dx.doi.org/10.1142/s0217979219400058.

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To analyze the influence of penetration resistance for different steel plate configurations, different steel plates impacted by various projectiles were studied using the LS-DYNA code. The calculation results obtained using the LS-DYNA code and prior experimental results reported in the literature agree well with the damaged image of projectiles penetrating steel plates and the initial residual velocity curve of the projectile. The Q235 steel constitutive model is modified based on the Johnson–Cook model. It can be concluded that the LS-DYNA code analysis is reliable when compared with the experimental results. We then used the LS-DYNA code to conduct an extensive study into the penetration resistance of monolithic, contact-type double-layered and gap-type double-layered targets with the same surface density, impacted by different projectiles. The failure mode of the steel plate, initial residual velocity, ballistic limit velocity, energy absorption and plastic deformation of the monolithic and double-layered plates were studied. The results in this paper can provide guidance for the design and application of structural protection using steel plates.

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Kabin, Ievgen, Zoya Dyka, Dan Klann, Marcin Aftowicz e Peter Langendoerfer. "Resistance of the Montgomery Ladder Against Simple SCA: Theory and Practice". Journal of Electronic Testing 37, n. 3 (giugno 2021): 289–303. http://dx.doi.org/10.1007/s10836-021-05951-3.

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AbstractThe Montgomery kP algorithm i.e. the Montgomery ladder is reported in literature as resistant against simple SCA due to the fact that the processing of each key bit value of the scalar k is done using the same sequence of operations. We implemented the Montgomery kP algorithm using Lopez-Dahab projective coordinates for the NIST elliptic curve B-233. We instantiated the same VHDL code for a wide range of clock frequencies for the same target FPGA and using the same compiler options. We measured electromagnetic traces of the kP executions using the same input data, i.e. scalar k and elliptic curve point P, and measurement setup. Additionally, we synthesized the same VHDL code for two IHP CMOS technologies, for a broad spectrum of frequencies. We simulated the power consumption of each synthesized design during an execution of the kP operation, always using the same scalar k and elliptic curve point P as inputs. Our experiments clearly show that the success of simple electromagnetic analysis attacks against FPGA implementations as well as the one of simple power analysis attacks against synthesized ASIC designs depends on the target frequency for which the design was implemented and at which it is executed significantly. In our experiments the scalar k was successfully revealed via simple visual inspection of the electromagnetic traces of the FPGA for frequencies from 40 to 100 MHz when standard compile options were used as well as from 50 MHz up to 240 MHz when performance optimizing compile options were used. We obtained similar results attacking the power traces simulated for the ASIC. Despite the significant differences of the here investigated technologies the designs’ resistance against the attacks performed is similar: only a few points in the traces represent strong leakage sources allowing to reveal the key at very low and very high frequencies. For the “middle” frequencies the number of points which allow to successfully reveal the key increases when increasing the frequency.

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Liu, Lin, e Marc M. Van Hulle. "Modeling the Surround of MT Cells and Their Selectivity for Surface Orientation in Depth Specified by Motion". Neural Computation 10, n. 2 (1 febbraio 1998): 295–312. http://dx.doi.org/10.1162/089976698300017773.

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The projective transformation onto the retina loses the explicit 3D shape description of a moving object. Theoretical studies show that the reconstruction of 3D shape from 2D motion information (shape from motion, SFM) is feasible provided that the first- and second-order directional derivatives of the 2D velocity field are available. Experimental recordings have revealed that the receptive fields of the majority of the cells in macaque area middle temporal (MT) display an antagonistic (suppressive) surround and that a sizable portion of these surrounds are asymmetrical. This has led to the conjecture that these cells provide a local measure for the directional derivatives of the 2D velocity field. In this article, we adopt a nonparametric and biologically plausible approach to modeling the role played by the MT surrounds in the recovery of the orientation in depth (the slant and tilt) of a moving (translating) plane. A three-layered neural network is trained to represent the slant and tilt from the projected motion vectors. The hidden units of the network have speed-tuning characteristics and represent the MT model neurons with their surrounds. We conjecture that the MT surround results from lateral inhibitory connections with other MT cells and that populations of these cells, with different surround types, code linearly for slant and tilt of translating planes.

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Yang, Chun-Hao, e Baba C. Vemuri. "Nested Grassmannians for Dimensionality Reduction with Applications". Machine Learning for Biomedical Imaging 1, IPMI 2021 (1 marzo 2022): 1–21. http://dx.doi.org/10.59275/j.melba.2022-234f.

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In the recent past, nested structure of Riemannian manifolds has been studied in the context of dimensionality reduction as an alternative to the popular principal geodesic analysis (PGA) technique, for example, the principal nested spheres. In this paper, we propose a novel framework for constructing a nested sequence of homogeneous Riemannian manifolds. Common examples of homogeneous Riemannian manifolds include the spheres, the Stiefel manifolds, and the Grassmann manifolds. In particular, we focus on applying the proposed framework to the Grassmann manifolds, giving rise to the nested Grassmannians (NG). An important application in which Grassmann manifolds are encountered is planar shape analysis. Specifically, each planar (2D) shape can be represented as a point in the complex projective space which is a complex Grassmann manifold. Some salient features of our framework are: (i) it explicitly exploits the geometry of the homogeneous Riemannain manifolds and (ii) the nested lower-dimensional submanifolds need not be geodesic. With the proposed NG structure, we develop algorithms for the supervised and unsupervised dimensionality reduction problems respectively. The proposed algorithms are compared with PGA via simulation studies and real data experiments and are shown to achieve a higher ratio of expressed variance compared to PGA.<br>The code is available at <a href='https://github.com/cvgmi/NestedGrassmann'>https://github.com/cvgmi/NestedGrassmann</a>

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Magier, Mariusz, e Marcin Gutowski. "CONCEPTION OF A “SILENT” MORTAR PROJECTILE. PART II – CALCULATIONS OF INTERNAL BALLISTIC PARAMETERS". PROBLEMY TECHNIKI UZBROJENIA 157, n. 2 (10 novembre 2021): 7–35. http://dx.doi.org/10.5604/01.3001.0015.5042.

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The paper presents a theoretical description of computer codes for solution of the major question of internal ballistics for a “silent” mortar projectile. The computer codes proved their usefulness by providing the characteristics of a shot for each correct configuration of the projectile and eliminat-ing automatically the solutions not complying with the accepted specifications. Additionally, the structure of the code facilitates the modifications of a system of equations and parameters of the model to assisting a designing process of other systems of firearms.

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