Lattice Construction Research Articles

Corrosion-Hydrogen Degradation of the Shukhov Lattice Construction Steels

The technical state of the 100-year-old Shukhov lattice towers (in cities Mykolayiv and Cherkasy in Ukraine) and the Adziogol Lighthouse, located at the mouth of the Dnipro river, under the project of genius Russian engineer V. G. Shukhov with a use of widespread at that time rivet connection, is analysed. The peculiarity of such lattice hyperboloid designs consists in a minimisation of metal capacity. These unique constructions should be saved as the monuments of industrial architecture.The towers were partially broken-down in 1944 and later restored with a use of the weld technologies, therefore the problem of the workability evaluation of the weld joints is added. The results of the expertise of the structures from the point of materials science and corrosion-mechanical aspects of this problem are presented. The chemical content, corrosion and mechanical properties of authentic and repair metal are studied and the reasons of fracture of welds are analysed. It was established that the in-bulk angle metal of Adziogol Lighthouse is characterised by the lowest corrosion resistance what can be connected with the steel hydrogenation in the conditions of the near Black Sea environment. This factor intensifies in-bulk material degradation and therefore causes a sensitivity of the weld metal to stress corrosion cracking.

Research on Data Integration of the Semantic Web Based on Ontology Learning Technology

Goal of ontology learning is to use machine learning and statistical techniques, by means of automatic or semi-automatic, and obtain the expected from the existing data resources. Web data integration based on ontology is web data mapping information in the source to the process of ontology concepts. The goal of semantic Web is to provide a computer for semantic Internet information can be understood, thus the computer to identify the information, and the automatic interpretation, exchange and processing. The paper presents the research on data integration of the semantic web based on ontology learning technology. Theory and experiments show that compared with the method of concept lattice construction algorithm has certain superiority. DOI : http://dx.doi.org/10.11591/telkomnika.v12i1.3889

Supersymmetric quiver gauge theories on the lattice

Abstract In this paper we detail the lattice constructions of several classes of supersymmetric quiver gauge theories in two and three Euclidean spacetime dimensions possessing exact supersymmetry at finite lattice spacing. Such constructions are obtained through the methods of topological twisting and geometric discretization of Euclidean Yang-Mills theories with eight and sixteen supercharges in two and three dimensions. We detail the lattice constructions of two-dimensional quiver gauge theories possessing four and eight supercharges and three-dimensional quiver gauge theories possessing eight supercharges.

A Formal Concept Analysis Approach to Data Mining: The QuICL Algorithm for Fast Iceberg Lattice Construction

Association rule mining (ARM) is the task of identifying meaningful implication rules exhibited in a data set. Most research has focused on extracting frequent item (FI) sets and thus fallen short of the overall ARM objective. The FI miners fail to identify the upper covers that are needed to generate a set of association rules whose size can be readily exploited by an end user. An alternative to FI mining can be found in formal concept analysis (FCA). FCA derives a lattice whose concepts identify closed FI sets and connections identify the upper covers. However, most FCA algorithms construct a complete lattice and therefore include item sets that are not frequent. An iceberg lattice, on the other hand, is a lattice whose concepts contain only FI sets. This paper presents the development of the Quick Iceberg Concept Lattice (QuICL) algorithm. QuICL uses recursion instead of iteration to navigate the lattice and establish connections, thereby eliminating costly processing incurred by past algorithms. The QuICL algorithm was evaluated against a leading FI miner and lattice construction algorithms using cited benchmarks. Results demonstrate that QuICL provides performance on the order of FI miners yet additionally derive the upper covers. Beyond this, QuICL has proved to be very efficient, providing an order of magnitude gains over other lattice construction algorithms.

A Graph Lattice Approach to Maintaining and Learning Dense Collections of Subgraphs as Image Features

Effective object and scene classification and indexing depend on extraction of informative image features. This paper shows how large families of complex image features in the form of subgraphs can be built out of simpler ones through construction of a graph lattice—a hierarchy of related subgraphs linked in a lattice. Robustness is achieved by matching many overlapping and redundant subgraphs, which allows the use of inexpensive exact graph matching, instead of relying on expensive error-tolerant graph matching to a minimal set of ideal model graphs. Efficiency in exact matching is gained by exploitation of the graph lattice data structure. Additionally, the graph lattice enables methods for adaptively growing a feature space of subgraphs tailored to observed data. We develop the approach in the domain of rectilinear line art, specifically for the practical problem of document forms recognition. We are especially interested in methods that require only one or very few labeled training examples per category. We demonstrate two approaches to using the subgraph features for this purpose. Using a bag-of-words feature vector we achieve essentially single-instance learning on a benchmark forms database, following an unsupervised clustering stage. Further performance gains are achieved on a more difficult dataset using a feature voting method and feature selection procedure.

Cyclic codes over [formula omitted

The ring in the title is perhaps the first noncommutative ring to have been used as alphabet for block codes. The original motivation was the construction of some quaternionic modular lattices from codes. The new application is the construction of space time codes obtained by concatenation from the Golden code. In this paper, we derive structure theorems for cyclic codes over that ring, and use them to characterize the lengths where self dual cyclic codes exist. These codes in turn give rise to formally self dual F4-codes.

A geometric construction of panel-regular lattices for buildings of types Ã2and C̃2

Using Singer polygons, we construct locally finite affine buildings of types ~A_2 and ~C_2 which admit uniform lattices acting regularly on panels. This construction produces very explicit descriptions of these buildings as well as very short presentations of the lattices. All but one of the ~C_2-buildings are necessarily exotic. To the knowledge of the author, these are the first presentations of lattices in buildings of type ~C_2. Integral and rational group homology for the lattices is also calculated.

Identificación de asociaciones y complicidades, vía-email, de un grupo de analistas de redes sociales: ¿Qué intercambian los rederos?

Research communities in the world are among the few social conglomerates that are permanently open with their surroundings, therefore they offer valuable information about its origins, development and future, and probably evidence about possible scientific paradigms that are in embryonic form in such groups. Although NSA is an approach that has been developed over the last 50 years, actually is possible see, around this topic, a budding research community which is looking its own maturation process in the social sciences. One way to search for this group is with the lattice construction through exchange of

High-dimensional integration: The quasi-Monte Carlo way

This paper is a contemporary review of QMC (‘quasi-Monte Carlo’) methods, that is, equal-weight rules for the approximate evaluation of high-dimensional integrals over the unit cube [0,1]s, wheresmay be large, or even infinite. After a general introduction, the paper surveys recent developments in lattice methods, digital nets, and related themes. Among those recent developments are methods of construction of both lattices and digital nets, to yield QMC rules that have a prescribed rate of convergence for sufficiently smooth functions, and ideally also guaranteed slow growth (or no growth) of the worst-case error as s increases. A crucial role is played by parameters called ‘weights’, since a careful use of the weight parameters is needed to ensure that the worst-case errors in an appropriately weighted function space are bounded, or grow only slowly, as the dimension s increases. Important tools for the analysis are weighted function spaces, reproducing kernel Hilbert spaces, and discrepancy, all of which are discussed with an appropriate level of detail.

Laser mode hyper-combs

Laser mode and frequency combs, as lasers, are commonly one-dimensional systems. Here we present a construction of multi-dimensional laser-mode lattices (mode hyper-combs) with unique properties. They are obtained from regular 1-dimensional combs by multi-frequency modulation in active mode-locking (AML). The hyper-comb, with near neighbor mode coupling and noise functioning as temperature, is mapped to interacting magnetic-spins lattices in the spherical-model which is one of the few statistical-mechanics systems soluble in all dimensions. The important result is that such systems have, in d>2 dimensions, a phase-transition to a global phase-ordered mode hyper-comb. It can therefore change the nature of AML lasers by capturing very broad coherent frequency bandwidths and obtaining ultimately short and robust pulses. Additionally, the hyper-combs can serve as a rare physical realization of the spherical-model in any dimension.

Two matrix-based lattice construction techniques

Let m and n be integers greater than 1. Given lattices A and B of dimensions m and n, respectively, a technique for constructing a lattice from them of dimension m+n-1 is introduced. Furthermore, if A and B possess bases satisfying certain conditions, then a second technique yields a lattice of dimension m+n-2. The relevant parameters of the new lattices are given in terms of the respective parameters of A,B, and a lattice C isometric to a sublattice of A and B. Denser sphere packings than previously known ones in dimensions 52, 68, 84, 248, 520, and 4098 are obtained.

On Lattice-Theoretical Construction of Matroids

Abstract This paper builds up a lattice-theoretical construction for all of matroids under isomorphism with the help of Galois isomorphisms among contexts. It discusses the lattice operations defined on this lattice construction with the direct sum between matroids.

Parallel Construction of Variable Precision Concept Lattice in Fuzzy Formal Context

Based on the fuzzy cut method, the fuzzy concept lattice was analyzed and researched and a new kind of concept lattice which called variable precision concept lattice was proposed. This kind of concept lattice can be constructed with every different confidence through selecting different level. Two corresponding construction methods, context cut method and concept cut method, were discussed in the two different angles, and some results were given. Furthermore, a case study was carried on.

Construction and Applicaton of Grey Concept Lattices

Grey numbers facilitate the representation of uncertainty not only for elements of a set, but also the set itself as a whole. This paper utilizes the notion of possibility degree from grey system theory coupled with the idea of dominance relation and partial order set (poset) from rough theory to represent uncertain information in a manner that maintains the degree of uncertainty of information for each tuple of the original data. Concept lattices of grey information system are constructed and a decision-making algorithm that combines with grey relational grade is described. A case study is used to demonstrate the supplier selection problem applying the proposed method. The research has concluded that the method is appropriate to use.

Chitin-binding proteins of Artemia diapause cysts participate in formation of the embryonic cuticle layer of cyst shells

The brine shrimp Artemia reproduces either ovoviviparously, producing free-swimming nauplii, or oviparously, producing encysted embryos (diapause cysts) able to cope with harsh and complex habitats. When the cysts enter diapause they are encased in a complex external shell that protects them from certain extreme environments. The genomic comparison of oviparous and ovoviviparous ovisacs has been described previously. We isolated three significantly up-regulated genes in oviparous oocytes and identified them as Arp-CBP (Artemia parthenogenetica chitin-binding protein) genes. Quantitative real-time PCR indicated that the expression of Arp-CBP genes gradually increases during diapause cyst formation and significant mRNA accumulation occurs during the ovisac stage of oviparous development. Moreover, in situ hybridization results demonstrated that Arp-CBP mRNAs are expressed in the embryo. Interestingly, the results of immune electron microscopy showed that all three Arp-CBPs are distributed throughout the cellular ECL (embryonic cuticle layer) of the cyst shell. Furthermore, knockdown of Arp-CBP by RNA interference resulted in marked changes in the composition of the embryonic cuticular layer. The fibrous layer of the cyst shell adopted a loose conformation and the inner and outer cuticular membranes exhibited marked irregularities when Arp-CBP expression was suppressed. Finally, an invitro recombinant protein-binding assay showed that all three Arp-CBPs have carbohydrate-binding activities. These findings provide significant insight into the mechanisms by which the ECL of Artemia cyst shell is formed, and demonstrate that Arp-CBPs are involved in construction of the fibrous lattice and are required for formation of the ECL of the cyst shell.

Ab initioinvestigation of graphene-based one-dimensional superlattices and their interfaces

We investigate structural and electronic properties of graphene-based one-dimensional (1D) superlattices by means of first-principles calculations. The 1D superlattices are modeled by three different chemical and structural modifications of the carbon lattice. We study partial hydrogenation of graphene, substitution of carbon-atom pairs by boron and nitrogen atoms, and incorporation of ribbons of the recently discovered silicene. Our investigations based on density functional theory provide accurate predictions of structural and electronic properties of all systems under consideration. In detail, the formation of 1D interfaces between two-dimensional honeycomb crystals is studied, including the construction of a coincidence lattice. The importance of the interface for the energy alignment and the Fermi-level position is proven. Finally, we discuss the results in light of the possible realization of a quasi-1D metal.

On the UMD constants for a class of iterated [formula omitted] spaces

Let 1<p≠q<∞ and (D,μ)=({±1},12δ−1+12δ1). Define by recursion: X0=C and Xn+1=Lp(μ;Lq(μ;Xn)). In this paper, we show that there exist c1=c1(p,q)>1 depending only on p, q and c2=c2(p,q,s) depending on p, q, s, such that the UMDs constants of Xnʼs satisfy c1n⩽Cs(Xn)⩽c2n for all 1<s<∞. Similar results will be showed for the analytic UMD constants. We mention that the first super-reflexive non-UMD Banach lattices were constructed by Bourgain. Our results yield another elementary construction of super-reflexive non-UMD Banach lattices, i.e. the inductive limit of Xn, which can be viewed as iterating infinitely many times Lp(Lq).

An explicit realization of logarithmic modules for the vertex operator algebra $\mathcal {W}_{p,p^{\prime }}$Wp,p′

By extending the methods used in our earlier work, in this paper, we present an explicit realization of logarithmic \documentclass[12pt]{minimal}\begin{document}$\mathcal {W}_{p,p^{\prime }}$\end{document}Wp,p′-modules that have L(0) nilpotent rank three. This was achieved by combining the techniques developed in [D. Adamović and A. Milas, “Lattice construction of logarithmic modules for certain vertex algebras,” Selecta Math., New Ser. 15, 535–561 (2009)10.1007/s00029-009-0009-z; e-print arXiv:0902.3417] with the theory of local systems of vertex operators.[J. Lepowsky and H. Li, Introduction to Vertex Operator Algebras and Their Representations, Progress in Mathematics Vol. 227 (Birkhäuser, Boston, 2003)] In addition, we also construct a new type of extension of \documentclass[12pt]{minimal}\begin{document}$\mathcal {W}_{p,p^{\prime }}$\end{document}Wp,p′, denoted by \documentclass[12pt]{minimal}\begin{document}$\mathcal {V}$\end{document}V. Our results confirm several claims in the physics literature regarding the structure of projective covers of certain irreducible representations in the principal block. This approach can be applied to other models defined via a pair screenings.

Directed Assembly of DNA-Functionalized Gold Nanoparticles Using Pyrrole–Imidazole Polyamides

Traditional methods for the construction of nanoparticle arrays and lattices exploit Watson-Crick base pairing of single-stranded DNA sequences as a proxy for self-assembly. Although this approach has been utilized in a variety of applications in nanoassembly, diagnostics, and biomedicine, the diversity of this recognition lexicon could be considerably increased by developing strategies that recognize the base-pairing landscape of double-stranded DNA (dsDNA) sequences. Herein we describe the first report of programmed gold nanoparticle (GNP) aggregation directed by the recognition of dsDNA sequences using pyrrole-imidazole polyamide-GNP (PA-GNP) conjugates. We demonstrate the reversibility and selectivity of this strategy for forming GNP aggregates in the presence of fully matched dsDNA sequences relative to dsDNA sequences containing one- and two-base-pair mismatches.

Construction of a Hermitian lattice without a basis of minimal vectors

It is known that infinitely many imaginary quadratic fields allow Hermitian lattices which are generated by minimal vectors but have no basis of minimal vectors. In this article we construct systematically such Hermitian lattices over other imaginary quadratic fields. These lattices are binary and unimodular. This construction requires specific non-principal ideals.