“Set of Strings” Framework for Big Data Modeling

The most complicated task for big data modeling in comparison with relational approach is its variety, being a consequence of heterogeneity of sources of data, accumulated in the integrated storage space. “Set of Strings” Framework (SSF) provides unified solution of this task by representation of database as updated finite set of facts, being strings, in which structure is defined by current metadatabase, which is also an updated set of the context-free generating rules. This chapter is dedicated to SSF formal and substantial description

Multiset-Based Knowledge Representation for the Assessment and Optimization of Large-Scale Sociotechnical Systems

This chapter is dedicated to a new knowledge representation model, providing convergence of classical operations research and modern knowledge engineering. Kernel of the introduced model is the recursively generated multisets, selected according to the predefined restrictions and optimization criteria. Sets of multisets are described by the so-called multiset grammars (MGs), being projection of a conceptual background of well-known string-generating grammars on the multisets universum. Syntax and semantics of MGs and their practice-oriented development—unitary multiset grammars and metagrammars—are considered

Augmented Post Systems: Syntax, Semantics, and Applications

Augmented Post systems (APS) are string-operating Prolog-like knowledge representation, affiliated with the “Set of Strings” Framework (SSF). APS descriptive and logical inference capabilities provide natural integration of Big Data with online analytic processing. This chapter is dedicated to strict formal definition of APS syntax, mathematical and operational semantics, and to its most valuable implementational issues, as well as to APS application to Big Data, Internet of Things, cyberphysical industry, and cybersecurity areas

Multiset-Based Assessment of Resilience of Sociotechnological Systems to Natural Hazards

The chapter describes multiset-based approach to the assessment of resilience/vulnerability of the distributed sociotechnological systems (DSTS) to natural hazards (NH). DSTS contain highly interconnected and intersected consuming and producing segments, and also resource base (RB), providing their existence and operation. NH impacts may destroy some local elements of these segments, as well as some parts of RB, thus initiating multiple chain effects, leading to negative consequences far away from the NH local strikes. To assess DSTS resilience to such impacts, multigrammatical representation of DSTS is used. A criterion of DSTS sustainability to NH, being generalization of similar criterion, known for industrial (producing) systems, is proposed. Application of this criterion to critical infrastructures is considered, as well as solution of the reverse problem, concerning subsystems of DSTS, which may stay functional after NH impact

Unitary Multiset Grammars an Metagrammars Algorithmics and Application

The chapter is dedicated to the algorithmics of unitary multiset grammars and metagrammars. Their application to some actual problems from the area of large-scale sociotechnical systems (STS) assessment and optimization is also considered: estimation of capabilities of the producing STS; amounts of resources, necessary to such STS for various orders completion; assessment of STS sustainability/vulnerability to various destructive impacts (natural disasters, technogenic catastrophes, mutual sanctions, etc.); and STS profit maximization, as well as works optimal distribution among non-antagonistic competing STS, operating in the market economy

Multi-Agent Implementation of Filtering Multiset Grammars

Chapter is dedicated to the application of multi-agent technology to generation of sets of terminal multisets (TMS) defined by filtering multiset grammars (FMG). Proposed approach is based on creation of multi-agent system (MAS), corresponding to specific FMG in such a way, that every rule of FMG is represented by independently acting agent. Such MAS provides high-parallel generation of TMS and may be effectively used in any proper hardware environment. Directions of further development of the proposed approach are discussed

Effect of buoyancy force on turbulent modes of complex heat transfer in an air-filled square cavity

Turbulent natural convection with the interaction of surface radiation in square enclosure has been numerically studied. The governing equations are solved contemporaneously by finite difference method to obtain the velocity, temperature and heat flux distributions. Turbulence has been modeled using the standard k-ε model. The change of convective and radiative Nusselt numbers with respect to time has been described. The analysis is carried out over a wide range of Rayleigh number from 108 to 1010. The effect of this key parameter on temperature and velocity distributions, convective and radiative Nusselt numbers has been investigated. The results clearly demonstrate a significant effect of buoyancy ratio on unsteady turbulent heat transfer

Comparative study of standard k–ε and k–ω turbulence models by giving an analysis of turbulent natural convection in an enclosure

Turbulent natural convection in a square cavity has been numerically studied. The mathematical model has been formulated in terms of the dimensionless stream function, vorticity and temperature using two standard turbulence models (k–ε and k–ω). For an obtaining of more accurate values of governing parameters close to the walls a special coordinate transformation has been used. Formulated partial differential equations along with the corresponding boundary conditions have been solved by the finite difference method. It has been shown that standard k–ε model is more accurate for the considered problem

Effect of thermal conductivity and emissivity of solid walls on time-dependent turbulent conjugate convective-radiative heat transfer

In the present study, the conjugate turbulent free convection with the thermal surface radiation in a rectangular enclosure bounded by walls with different thermophysical characteristics in the presence of a local heater is numerically studied. The effects of surface emissivity and wall materials on the air flow and the heat transfer characteristics are the main focus of the present investigation. The conjugate convective heat transfer for the fluid (air), described in terms of linear momentum, continuity, and energy equations combined with k-ε turbulence model, is predicted by using the finite difference method. The results for the isotherms, streamlines, and average Nusselt numbers along the heat source are presented. The numerical experiments show that an increase in thermal conductivity of solid walls illustrates the enhancement of heat transfer. Eventually, the main result obtained in this work provides a good technical support for the development and research of energy efficient building materials

A review of nanocomposite-modified electrochemical sensors for water quality monitoring

Electrochemical sensors play a significant role in detecting chemical ions, molecules, and pathogens in water and other applications. These sensors are sensitive, portable, fast, inexpensive, and suitable for online and in-situ measurements compared to other methods. They can provide the detection for any compound that can undergo certain transformations within a potential window. It enables applications in multiple ion detection, mainly since these sensors are primarily non-specific. In this paper, we provide a survey of electrochemical sensors for the detection of water contaminants, i.e., pesticides, nitrate, nitrite, phosphorus, water hardeners, disinfectant, and other emergent contaminants (phenol, estrogen, gallic acid etc.). We focus on the influence of surface modification of the working electrodes by carbon nanomaterials, metallic nanostructures, imprinted polymers and evaluate the corresponding sensing performance. Especially for pesticides, which are challenging and need special care, we highlight biosensors, such as enzymatic sensors, immunobiosensor, aptasensors, and biomimetic sensors. We discuss the sensors’ overall performance, especially concerning real-sample performance and the capability for actual field application