Above-mentioned Property Research Articles

Stealthy Messaging: Leveraging Message Queuing Telemetry Transport for Covert Communication Channels

Covert channel methods are techniques for improving privacy and security in network communications. These methods consist of embedding secret data within normal network channels, making it more difficult for unauthorized parties to detect such data. This paper presents a new approach for creating covert channels using the Message Queuing Telemetry Transport (MQTT) protocol, widely used in the context of the Internet of Things (IoT). The proposed method exploits storage channels by altering the field length of MQTT messages. Our solution leverages well-known one-way mathematical functions to ensure that data remain hidden from third parties observing the MQTT stream. In this way, we ensure that not only the content of the communication is preserved but also that the communication itself takes place. We conducted a security analysis to show that our solution offers the above-mentioned property even against severe threats, such as an adversary being able to observe all the messages exchanged in the network (even in the clear). Finally, we conducted an overhead analysis of our solution both in terms of the time required to perform the required operations and of the bytes to send. Our study shows that our solution adds no significant time overhead, and the additional overhead in terms of transmitted bytes remains within acceptable limits.

A property of meets in slim semimodular lattices and its application to retracts

Slim semimodular lattices were introduced by G. Grätzer and E. Knapp in 2007, and they have intensively been studied since then. These lattices can be given by \(\mathcal{C}_1\)-diagrams, defined by the author in 2017. We prove that if x and y are incomparable elements in such a lattice L, then their meet has the property that the interval \([x \wedge y, x]\) is a chain, this chain is of a normal slope in every \(\mathcal{C}_1\)-diagram of L, and except possibly for x, the elements of this chain are meet-reducible.In the direct square K1 of the three-element chain, let X1 and A1 be the set of atoms and the sublattice generated by 0 and the coatoms, respectively. Denote by K2 the unique eight-element lattice embeddable in K1. Let A2 be the sublattice of K2 consisting of 0, 1, the meet-reducible atom, and the join-reducible coatom. Let X2 stand for the singleton consisting of the doubly reducible element of K2. For i = 1, 2, we apply the above-mentioned property of meets to prove that whenever Ki is a sublattice and Si is a retract of a slim semimodular lattice, then \(A_i \subseteq S_i\) implies that \(X_i \subseteq S_i\).

On certain analogues of linkedness and supercompactness

Natural generalizations of properties of the family linkedness and the topological space supercompactness are considered. We keep in mind reinforced linkedness when nonemptyness of intersection of preassigned number of sets from a family is postulated. Analogously, supercompactness is modified: it is postulated the existence of an open subbasis for which, from every covering (by sets of the subbasis), it is possible to extract a subcovering with a given number of sets (more precisely, not more than a given number). It is clear that among all families having the reinforced linkedness, one can distinguish families that are maximal in ordering by inclusion. Under natural and (essentially) “minimal”' conditions imposed on the original measurable structure, among the mentioned maximal families with reinforced linkedness, ultrafilters are certainly contained. These ultrafilters form subspaces in the sense of natural topologies corresponding conceptually to schemes of Wallman and Stone. In addition, maximal families with reinforced linkedness, when applying topology of the Wallman type, have the above-mentioned property generalizing supercompactness. Thus, an analogue of the superextension of the $T_1$-space is realized. The comparability of “Wallman”' and “Stone”' topologies is established. As a result, bitopological spaces (BTS) are realized; for these BTS, under equipping with analogous topologies, ultrafilter sets are subspaces. It is indicated that some cases exist when the above-mentioned BTS is nondegenerate in the sense of the distinction for forming topologies. At that time, in the case of “usual” linkedness (this is a particular case of reinforced linkedness), very general classes of spaces are known for which the mentioned BTS are degenerate (the cases when origial set, i.e., “unit”' is equipped with an algebra of sets or a topology).

Extension of Strongins Global Optimization Algorithm to a Function Continuous on a Compact Interval

The Lipschitz continuous property has been used for a long time to solve the global optimization problem and continues to be used. Here we can mention the work of Piyavskii, Yevtushenko, Strongin, Shubert, Sergeyev, Kvasov and others. Most papers assume a priori knowledge of the Lipschitz constant, but the derivation of this constant is a separate problem. Further still, we must prove that an objective function is really Lipschitz, and it is a complicated problem too. In the case where the Lipschitz continuity is established, Strongin proposed an algorithm for global optimization of a satisfying Lipschitz condition on a compact interval function without any a priori knowledge of the Lipschitz estimate. The algorithm not only finds a global extremum, but it determines the Lipschitz estimate too. It is known that every function that satisfies the Lipchitz condition on a compact convex set is uniformly continuous, but the reverse is not always true. However, there exist models (Arutyunova, Dulliev, Zabotin) whose study requires a minimization of the continuous but definitely not Lipschitz function. One of the algorithms for solving such a problem was proposed by R. J. Vanderbei. In his work he introduced some generalization of the Lipchitz property named $\varepsilon$-Lipchitz and proved that a function defined on a compact convex set is uniformly continuous if and only if it satisfies the $\varepsilon$-Lipchitz condition. The above-mentioned property allowed him to extend Piyavskii’s method. However, Vanderbei assumed that for a given value of $\varepsilon$ it is possible to obtain an associate Lipschitz $\varepsilon$-constant, which is a very difficult problem. Thus, there is a need to construct, for a function continuous on a compact convex domain, a global optimization algorithm which works in some way like Strongin’s algorithm, i.e., without any a priori knowledge of the Lipschitz $\varepsilon$-constant. In this paper we propose an extension of Strongin’s global optimization algorithm to a function continuous on a compact interval using the $\varepsilon$-Lipchitz conception, prove its convergence and solve some numerical examples using the software that implements the developed method.

Rings in which every regular locally principal ideal is projective

Abstract In this article, we study the class of rings in which every regular locally principal ideal is projective called LPP-rings. We investigate the transfer of this property to various constructions such as direct products, amalgamation of rings, and trivial ring extensions. Our aim is to provide examples of new classes of commutative rings satisfying the above-mentioned property.

Inherent Equalization of Lithium-Ion Batteries Based on Leakage Current

This paper studies inherent equalization of lithium-ion batteries based on leakage current. Through constant potential load tests, the leakage current proves to vary exponentially with applied voltage and cell temperature. A hopping model is applied to the solid-electrolyte interface to explain the above-mentioned property. Stability of cell voltages is theoretically proved, which guarantees that stored charges gather near individual cell capacities at a steady state. Simulations agree well with measurements. A photovoltaic system is operated for 11 months during which cell voltages are balanced without external circuit. As far as leakage currents are close, balance of cell voltages is kept.

Online Semantic Object Segmentation for Vision Robot Collected Video

Video segmentation is the foundation of many senior computer vision applications. For robotic vision applications, video object segmentation is facing more difficulties. Since the videos are usually collected from those complicated scenes and the camera perspective may be static for some time, object saliency and motion clues which are widely used in traditional video segmentation approaches could be unreliable. Besides, its online processing ability is of crucial importance. In this paper, we propose an online video object segmentation method, which is organized as a segmentation-by-detection framework. It first effectively segments out meaningful objects in short video frame batches with the help of object detectors, and then the segmentation of different batches can be associated with each other via bi-directional notebook based connecting strategy. Experiments conducted on public available datasets verify the above-mentioned property and show good performance of the proposed method.

Understanding grain evolution in additive manufacturing through modeling

Variability in the mechanical properties of additively manufactured metal parts is a key concern for their application in service. One of the parameters affecting the above-mentioned property is solidification texture which is driven by scan patterns and other process variables. Understanding of how these textures arise in the AM process can provide a pathway to control these features which ultimately decide the final structural material properties. In this work, a Cellular Automata (CA) based two-dimensional microstructure model is formulated and implemented to understand grain evolution in AM. Grain evolution in multilayer depositions using various scan patterns in Directed Energy Deposition (DED), Metal Laser Sintering/Selective Laser Melting (MLS/SLM), and Electron Beam Melting (EBM) is presented and qualitatively compared with reported literature. Results show strong correlation of scan patterns with evolving grain orientations. Variability in grain size and orientation evolution during SLM and EBM processing of metallic materials showed direct influence by exposure to different cooling rates and thermal gradients. The similarities between the simulated and reported results lead us to conclude CA based modeling for predicting grain orientation and size in metal AM processes is useful for prediction of continuum level structural properties at global and local length scales.

Submodularity and its application to some global constraints

Submodularity defines a general framework rich of important theoretical properties while accommodating numerous applications. Although the notion has been present in the literature of Combinatorial Optimization for several decades, it has been overlooked in the analysis of global constraints. The current work illustrates the potential of submodularity as a powerful tool for such an analysis. In particular, we show that the cumulative constraint, when all tasks are identical, has the submodular/supermodular representation property, i.e., it can be represented by a submodular/supermodular system of linear inequalities. Motivated by that representation, we show that the system of any two (global) constraints not necessarily of the same type, each bearing the above-mentioned property, has an integral relaxation given by the conjunction of the linear inequalities representing each individual constraint. This result is obtained through the use of the celebrated polymatroid intersection theorem.

Degeneration of the Hilbert pairing in formal groups over local fields

For an arbitrary local field K (a finite extension of the field Qp) and an arbitrary formal group law F over K, we consider an analog cF of the classical Hilbert pairing. A theorem by S.V. Vostokov and I.B. Fesenko says that if the pairing cF has a certain fundamental symbol property for all Lubin–Tate formal groups, then cF = 0. We generalize the theorem of Vostokov–Fesenko to a wider class of formal groups. Our first result concerns formal groups that are defined over the ring OK of integers of K and have a fixed ring O0 of endomorphisms, where O0 is a subring of OK. We prove that if the symbol cF has the above-mentioned symbol property, then cF = 0. Our second result strengthens the first one in the case of Honda formal groups. The paper consists of three sections. After a short introduction in Section 1, we recall basic definitions and facts concerning formal group laws in Section 2. In Section 3, we state and prove two main results of the paper (Theorems 1 and 2). Refs. 8.

Bound of earthquake input energy to building structure considering shallow and deep ground uncertainties

The bound of earthquake input energy to building structures is clarified by considering shallow and deep ground uncertainties and soil–structure interaction. The ground motion amplification in the shallow and deep ground is described by a one-dimensional wave propagation theory. The constant input energy property to a swaying–rocking model with respect to the free-field ground surface input regardless of the soil property is used effectively to derive a bound. An extension of the previous theory for the engineering bedrock surface motion to a general earthquake ground motion model at the earthquake bedrock is made by taking full advantage of the above-mentioned input energy constant property. It is shown through numerical examples that a tight bound of earthquake input energy can be derived for the shallow and deep ground uncertainties.

Assortment Optimisation Under a General Discrete Choice Model: A Tight Analysis of Revenue-Ordered Assortments

A central problem in revenue management, known as the assortment problem, consists in deciding which subset of products to offer to consumers in order to maximise revenue. A simple and natural strategy is to select the best assortment out of all those that are constructed by fixing a threshold revenue r and then choosing all products with revenue at least r. This is known as the revenue-ordered assortments strategy. The main contribution of this paper is a precise analysis of how well revenue-ordered assortments approximate the optimum revenue when customers are rational in the following sense: the probability of selecting a specific product (including the no-choice option) from the set being offered cannot increase if the offer set is enlarged. The corresponding discrete choice models form a broad class of models which includes all discrete choice models based on random utility. Our analysis of revenue-ordered assortments match and unify known results for certain models, and improves the best known results for others, such as for the Mixed Multinomial Logit model recently studied by Rusmevichientong et al (2014). An appealing feature of our analysis is that it is simple and relies only on the above-mentioned rationality property, and yet it is best possible even for very specific models within the class. We also show that a large class of problems known as envy-free pricing problems can be seen as assortment problems for a specifically constructed discrete choice model that satisfies the rationality property. In this context, revenue-ordered assortments turn out to be equivalent to the well-studied uniform pricing strategy.

Electrochemical determination of bisphenol A based on PHD/MWCNTs modified glassy carbon electrode

A novel electrochemical sensor for the determination of bisphenol A (BPA) was fabricated by block polyelectrolyte composite films, which composed of diblock polyelectrolyte poly (2-hydroxyethyl methacrylate)-b-poly (2-(dimethylamino) ethyl methacrylate) (PHEMA-b-PDMAEMA, noted as PHD in the later content) and multi-walled carbon nanotubes (MWCNTs). The tertiary amino groups of PDMAEMA can be protonated at physiological pH. The protonated PDMAEMA can thus interact with the negatively charged BPA through electrostatic attraction to increase the BPA sorption capacity and enhance the ability for highly sensitive detection of BPA. The PHD/MWCNTs composite films combine the electrocatalytic property of MWCNTs and the electrostatic attraction of protonated PHD. Because of the above-mentioned excellent property of the composite films, the PHD/MWCNTs/glassy carbon electrode exhibited good electrocatalytic activity to electrooxidation of BPA. The wide linear response range of the BPA sensor was from 4.56 × 10−5 g L−1 to 2.28 × 10−2 g L−1 with a lower detection limit of 2.28 × 10−6 g L−1 (S/N = 3) and high sensitivity 2442.86 μA L g−1 cm−2. The current reached the steady-state current with a shorter response time less than 4 s. The proposed method was successfully applied to determine BPA in real samples (PVC food package, milk, tap water and pond water) and satisfactory results were obtained. These results indicated that the block polyelectrolyte composite have potential applicability of the BPA sensor.

Mechanism and bounding of earthquake energy input to building structure on surface ground subjected to engineering bedrock motion

The mechanism of earthquake energy input to building structures is clarified by considering the surface ground amplification and soil–structure interaction. The earthquake input energies to superstructures, soil–foundation systems and total swaying–rocking system are obtained by taking the corresponding appropriate free bodies into account and defining the energy transfer functions. It has been made clear that, when the ground surface motion is white, the input energy to the swaying–rocking model is constant regardless of the soil property (input energy constant property). The upper bound of earthquake input energy to the swaying–rocking model is derived for the model including the surface ground amplification by taking full advantage of the above-mentioned input energy constant property and introducing the envelope function for the transfer function of the surface ground amplification. Extension of the theory to a general earthquake ground motion model at the engineering bedrock is also made by taking full advantage of the above-mentioned input energy constant property.

Sharp estimates regarding the remainder of the alternating harmonic series

In the present paper we obtain enhanced estimates regarding the remainder of the alternating harmonic series. More precisely, we show that 1 4n2 +a < ∣ ∣∣ ∣ ∣ n ∑ k=1 (−1)k−1 1 k − (−1)n−1 1 2n − ln2 ∣ ∣∣ ∣ ∣ 1 4n2 +b , for all n ∈N , with a = 2 and b = 2(3−4 ln2) 2 ln2−1 = 1.177398899 . . . . In addition, the constants a and b are the best possible with the above-mentioned property. Mathematics subject classification (2010): 11Y60, 40A05, 41A44, 33B15.

Polyhedral Aspects of Stable Marriage

In the setting of the stable matching (SM) problem, it has been observed that some of the man-woman pairs cannot be removed although they participate in no stable matching, since such a removal would alter the set of solutions. These pairs are yet to be identified. Likewise (and despite the sizeable literature), some of the fundamental characteristics of the SM polytope (e.g., its dimension, its facets, etc.) have not been established. In the current work, we show that these two seemingly distant open issues are closely related. More specifically, we identify the pairs with the above-mentioned property and present a polynomial algorithm for producing a set of minimal preference lists. We utilize this result in the context of two different representations of the SM structure (rotation-poset graph and algebraic formulation) and derive the dimension of the SM polytope to obtain all alternative minimal linear descriptions.

Finite groups whose irreducible Brauer characters have prime power degrees

Let G be a finite group and let p be a prime. In this paper, we classify all finite quasisimple groups in which the degrees of all irreducible p-Brauer characters are prime powers. As an application, for a fixed odd prime p, we classify all finite nonsolvable groups with the above-mentioned property and having no nontrivial normal p-subgroups. Furthermore, for an arbitrary prime p, a complete classification of finite groups in which the degrees of all nonlinear irreducible p-Brauer characters are primes is also obtained.

El Mayorazgo de Sartenejas en la Venezuela Colonial 1740-1858

El proceso de incorporación de la tierra al dominio privadoque se inició, en lo que hoy es Venezuela, en la segundamitad del siglo XVI por vía de mercedes, continuó en el XVIIbasándose en litigios, compras y venta de la tierra, ya parael XVIII lo vemos a través del sistema de ocupación. En ese proceso quienes salieron favorecidos fueron aquellos grupos descendientes de los primeros conquistadores que más tarde controlaron la vida económica y política de Caracas. Algunas familias procedentes de aquellos conquistadores decidieron convertir sus bienes en mayorazgos, logrando a través de esa institución perpetuar en la familia la propiedad. En Venezuela aparentemente existieron tres mayorazgos, dos de los cuales estaban ligados a la familia Bolívar y un tercero a los Cornieles en la ciudad de Trujillo. Sin embargo, hemos podido constatar más de 22 mayorazgos y uno de ellos es el de Sartenejas fundado en 1740 por Lorenzo Antonio de Ponte y Martínez de Villegas, según la ley 33 de Toro. A dicha hacienda estuvieron vinculadas tres “nobles” familias de raigambre en la Venezuela Colonial. Los Mixares, Ponte y Tovar que estuvieron unidas a través de alianzas matrimoniales para conservar sus bienes.

RINGS WHOSE CYCLIC MODULES ARE DIRECT SUMS OF EXTENDING MODULES

AbstractDedekind domains, Artinian serial rings and right uniserial rings share the following property: Every cyclic right module is a direct sum of uniform modules. We first prove the following improvement of the well-known Osofsky-Smith theorem: A cyclic module with every cyclic subfactor a direct sum of extending modules has finite Goldie dimension. So, rings with the above-mentioned property are precisely rings of the title. Furthermore, a ring R is right q.f.d. (cyclics with finite Goldie dimension) if proper cyclic (≇ RR) right R-modules are direct sums of extending modules. R is right serial with all prime ideals maximal and ∩n ∈ ℕJn = Jm for some m ∈ ℕ if cyclic right R-modules are direct sums of quasi-injective modules. A right non-singular ring with the latter property is right Artinian. Thus, hereditary Artinian serial rings are precisely one-sided non-singular rings whose right and left cyclic modules are direct sums of quasi-injectives.

Criteria for analyticity of subordinate semigroups

Let ψ be a Bernstein function. A. Carasso and T. Kato obtained necessary and sufficient conditions for ψ to have the property that ψ(A) generates a quasibounded holomorphic semigroup for every generator A of a bounded C0-semigroup in a Banach space, in terms of some convolution semigroup of measures associated with ψ. We give an alternative to Carasso-Kato’s criterion, and derive several sufficient conditions for ψ to have the above-mentioned property.