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Finica Ivanov

Reproductive Parameters of Porcellium Collicola (Verhoeff, 1907) and Trachelipus Arcuatus (Buddelund, 1885) (Crustacea: Isopoda: Oniscidea) in South Romania

Porcellium collicola (Verhoeff, 1907) and Trachelipus arcuatus (Budde-Lund, 1885) (Crustacea: Isopoda: Oniscidea) are two terrestrial isopod species inhabiting the leaf litter of oak forests in South Romania. This paper presents the size of reproductive females, fecundity (the number of eggs for a female for a brood), fertility (the number of larvae or mancas per female) and the relationship between the number of eggs or mancas per brood pouch and the total body length of pregnant females. In Porcellium collicola populations' reproductive females had a total body length of 3.3 to 7.3 mm, average fecundity was 18.60±7.10 eggs per female and average number of mancas per female was 10.29±8.05. In Trachelipus arcuatus the total body length of reproductive females was between 9.80 - 16.60 mm and the average number of eggs per brood per female was 55.60±21.71. A direct correlation between the size of pregnant females and fecundity and fertility was established for Porcellium collicola.

Open access

V. Ivanov

Abstract

The paper discusses the aspects of building a system for color light effects in homes of the future using a FPGA-based embedded microprocessor. It is also discussed some opportunities for further development in order to improve the conditions of life of the inhabitants of the homes of the future.

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Vladimir N. Ivanov

Abstract

This paper discusses the development of a complex device for Traffic Light Control. The device is based on a PicoBlaze microprocessor embedded in Spartan6 FPGA. Its benefits for the purposes of transport flows management are discussed.

Open access

Kaspars Ivanovs

Abstract

During the last century a large portion of small and medium-sized rivers in Latvia were channelized, hydroelectric power stations were also built, which led to changes in the hydrodynamic conditions, geomorphological structure, as well as a change in the fish fauna. Fish are an integral part of any community in natural or man-made bodies of water. They actively participate in maintaining the system, balancing/equilibrium, energy, substance transformation and biomass production. They are able to influence other organisms in the ecosystem in which they live. The aim of the paper “Pike distribution and feeding comparisons in natural and historically channelized river sections” is to find out what pike feed on in different environments in Latvian rivers, such as natural and straightened river sections, as well as what main factors determine the composition of their food. Several points were assessed during the course of the study: the impact of environmental conditions on the feeding habits and the distribution of pike; the general feeding habits of predators in Latvian rivers; the feeding differences of predators in natural and straightened river sections; and lastly, rhithral and pothamal habitats were compared. The study was based on data from 2014 and 2015 on fish fauna monitoring. During the study, 347 pike were collected from 136 plots using electrofishing method.

Open access

Gheorghe Duca, Maria Nedealcov and Ivanov Ivanov

Abstract

Although it is considered that the socio-economic impact over the last decades on surface water quality is significant, the role of changing regional climate that is manifested by the intensification of desertification process is crucial. In this context, it is important to know the current trends of change in total runoff of surface of surface waters in the context of increase of desertification degree of the regional climate attested in recent years

Open access

V. Bobrovs and G. Ivanovs

Comparison of Different Modulation Formats and their Compatibility with WDM Transmission System

In the work, the intensity and phase modulation methods are compared for different versions of the wavelength division multiplexing (WDM) system. Binary and multilevel code formats are evaluated numerically, with OptSim simulation software at the bit rate of 10 and 40 Gbit/s, using long-fiber spans and dispersion compensation technique. The problems to be overcome at exploitation of multiterabit WDM systems based on 40 Gbit/s optical transmissions are: chromatic dispersion (CD), polarization-mode dispersion (PMD), dispersion slope, and nonlinear effects of the transmission line. We have investigated the potentialities of modulation formats for 40 Gbit/s WDM networks where most of the listed problems are avoided. It is shown that Duobinary and differential phase shift keying (DPSK) modulation formats are perfectly suitable for ultra-high spectral efficient WDM systems and possess high resistance to dispersion and nonlinear optical effects (NOE).

Open access

Krastyu Ivanov Krastev

Abstract

The analysis of the religious extremism manifestation objectively reveals as independent the following variables E – Existence, C – Capabilities, I – Intentions and T – Targets. The essence of the proposed analytical model is the fact that if some of the mentioned variables is not presented it is practically impossible for religious extremism to manifest in the society and become violent. The paper describes an analytical model of religious manifestation model, based on some variables and results of research of religious extremist activities in Bulgaria.

Open access

Gh. Duca, Maria Nedealcov and Violeta Ivanov

Abstract

Aridity in new climatic conditions requires indexes which could adequately explain this process. All the more so, the quantities of atmospheric precipitations also continue to increase on the background of the temperatures increase in the conditions of the Republic of Moldova. Their variable character in the last period of time with the installation of dry and droughty periods alternating with rainy flood-provoking periods determines the selection of the most optimal ecometric indexes that could correctly explain the occurrence of pronounced desertification in the last period of time.

Open access

Sabin Ivanov Subev

Abstract

One of the essential issues in the field of public procurements are the disputes, arisen between the Assigning authority and the participant, selected for a contractor in pursuance of the implementation of the concluded contact for public procurement. The paper considers the possibility of looking at the disputes in a contract according to a public procurement of arbitration.

Open access

Artur Korniłowicz, Ievgen Ivanov and Mykola Nikitchenko

Summary

We show that the set of all partial predicates over a set D together with the disjunction, conjunction, and negation operations, defined in accordance with the truth tables of S.C. Kleene’s strong logic of indeterminacy [17], forms a Kleene algebra. A Kleene algebra is a De Morgan algebra [3] (also called quasi-Boolean algebra) which satisfies the condition x¬:xy¬ :y (sometimes called the normality axiom). We use the formalization of De Morgan algebras from [8].

The term “Kleene algebra” was introduced by A. Monteiro and D. Brignole in [3]. A similar notion of a “normal i-lattice” had been previously studied by J.A. Kalman [16]. More details about the origin of this notion and its relation to other notions can be found in [24, 4, 1, 2]. It should be noted that there is a different widely known class of algebras, also called Kleene algebras [22, 6], which generalize the algebra of regular expressions, however, the term “Kleene algebra” used in this paper does not refer to them.

Algebras of partial predicates naturally arise in computability theory in the study on partial recursive predicates. They were studied in connection with non-classical logics [17, 5, 18, 32, 29, 30]. A partial predicate also corresponds to the notion of a partial set [26] on a given domain, which represents a (partial) property which for any given element of this domain may hold, not hold, or neither hold nor not hold. The field of all partial sets on a given domain is an algebra with generalized operations of union, intersection, complement, and three constants (0, 1, n which is the fixed point of complement) which can be generalized to an equational class of algebras called DMF-algebras (De Morgan algebras with a single fixed point of involution) [25]. In [27] partial sets and DMF-algebras were considered as a basis for unification of set-theoretic and linguistic approaches to probability.

Partial predicates over classes of mathematical models of data were used for formalizing semantics of computer programs in the composition-nominative approach to program formalization [31, 28, 33, 15], for formalizing extensions of the Floyd-Hoare logic [7, 9] which allow reasoning about properties of programs in the case of partial pre- and postconditions [23, 20, 19, 21], for formalizing dynamical models with partial behaviors in the context of the mathematical systems theory [11, 13, 14, 12, 10].