An interactive method for teaching circuit model construction for complex interconnected acoustic systems

While interconnected systems proliferate in nowadays computing and communications technology there are few reports investigating their security. In this paper, new efficient models are developed and evaluated for analyzing the security-related behavior of computing architectures and networks comprising complex interconnected communication systems adapted towards a generalized analysis. These models, based on Markov processes, allow calculation of critical security factors, related to intrusion detection, of such interconnected systems components and the evaluation of the associated security mechanisms. Although, at this step two interconnected systems are analyzed, the systematic model introduced allows for a generalized model of N interconnected systems. We herein show the principles of such an analysis. Security parameters calculation and Security mechanisms evaluation may support the risk analysis and the decision making process in resolving the trade-offs between security and quality of service characteristics corresponding to the complex interconnected computing and communication systems.

The potential for capacity increase in multiple-antenna wireless communication systems has drawn considerable attention to space-time codes. However, most of the existing space-time code construction methods have assumed ideal channel models: either quasi-static fading or fast fading. In this work, we propose a systematic space-time trellis code construction method for correlated fading channels. We derive the performance criteria that take into account both spatial and temporal channel correlation, assuming that the space-time correlation matrix is of full rank. Moreover, we introduce a new design criterion and analyze the properties of the space-time trellis codes satisfying the proposed criterion. Using the design criterion, we develop a code construction procedure that jointly considers diversity advantage and coding advantage for an arbitrary number of transmit antennas and any memoryless modulation. The flexibility of the proposed code construction method is demonstrated by designing space-time trellis codes for two, three, and four transmit antennas with quaternary phase-shift keying (QPSK), 8PSK (phase-shift keying), and 4ASK (amplitude-shift keying) modulations. The simulation results demonstrate that not only can our method generate new codes for an arbitrary number of antennas, but in some special cases, where previously proposed codes exist, our codes also perform very well.

Many modern control systems become gradually more complicated and, consequently, the approach to control design approaches is both difficulty and complex. Moreover, if such a complex interconnected system is subjected to non‐smooth nonlinearities in the actuator, then unexpected difficulties, degradation or, even worse, instability will arise in the system performance. Therefore, a new decentralized sliding mode control (DSMC) approach for such a class of complex interconnected systems subjected to non‐smooth (deadzone) nonlinearities is proposed in this paper. Based on sliding mode control (SMC) theory, the proposed DSMC laws guarantee the global reaching condition of the sliding mode in uncertain complex interconnected systems with deadzone nonlinearities, that is, they can ensure that the sliding mode is reached in finite time and with prescribed transient behavior. In the sliding mode, the investigated uncertain complex interconnected system with deadzone nonlinearities in the actuator still are insensitive to system uncertainties and external disturbances. The proposed DSMC laws can work effectively for uncertain complex interconnected systems either with or without deadzone nonlinearities in the actuator. However, this cannot be guaranteed by the traditional DSMC design for systems without input deadzone nonlinearities. Furthermore, the sliding motion can be controlled to converge within a specified exponential speed. Finally, two illustrative examples with a series of computer simulations are presented to demonstrate the effectiveness of the proposed DSMC laws.

The traditional four-bar mechanism is renowned for its simple structure, dependable performance, and wide range of applications. The single-degree-of-freedom (DOF) four-bar multi-mode planar mechanism (MMPM) is a type of four-bar mechanism that not only has the structural characteristics of the traditional four-bar mechanisms but also can achieve multiple motion modes by changing its structure. It has the advantage of performing diverse functions while conserving resources, which opens up new possibilities for research and application of the four-bar mechanism. However, due to the lack of a systematic configuration construction method, the design and application of single-DOF four-bar MMPMs are seriously limited. This paper presents a systematic method to construct a set of single-DOF four-bar MMPMs based on the loop equations and the proposed multi-mode modules (MMMs). First, depending on the loop equations, the four-bar planar mechanism containing two branches is identified by the corresponding branch graphs. Then, three kinds of MMMs are systematically proposed for the first time, helping the identified mechanism realize multiple motion modes. Subsequently, single-DOF four-bar MMPMs are constructed by replacing the specific component of the planar mechanism with the MMMs. Furthermore, the replacement rules of MMMs and the corresponding construction steps are summarized. Finally, 14 kinds of single-DOF four-bar MMPMs are listed, and the corresponding multi-mode motion analysis is discussed at the end of this paper. The proposed method is a straightforward one, which will provide great convenience for the configuration design of single-DOF four-bar MMPMs and promote the development and application of MMPMs.

The purpose of the study. The purpose of the study is to model a generalized system of indicators of economic security of the regions of the Russian Federation. The topic of the study is relevant, since the prevention of crisis situations, the organization of stable functioning of regional economies, the development of territories and the growth of the standard of living of the population necessitate constant monitoring of the economic security of the regions of Russia, which is based on the modeling of a system of indicators, because socioeconomic development is a complex system of interconnections, various components of the economy.Data and methods. The normative and legal documents of the government bodies of the Russian Federation, official data of the Federal State Statistics Service, the Unified Interdepartmental Information and Statistical System and the Ministry of Finance of the Russian Federation were used as the information and empirical base of the study. The indicators were selected based on the works of Russian scientists and Decree of the President of the Russian Federation dated May 13, 2017 No. 208 “On the Strategy of Economic Security of the Russian Federation for the period up to 2030”. The method of factor analysis - principal component analysis was used in the formation and modeling of a generalized system of indicators of economic security of regions.Solutions and results. To achieve this goal, at the initial stage of the study, a system of indicators was formed, consisting of 26 indicators characterizing the production, financial, social and other aspects of the life of the regions that determine economic security. The information compression method, the principal component analysis, were applied to the selected indicator system. When choosing the number of principal components (factors), we relied on the eigenvalues of the principal components (Kaiser Criterion) and their contribution to the overall variance of the initial features. Seven principal components were identified. At the same time, their total contribution to the total variance was 78.45%, which is a sufficient condition for the formation of components. The best interpretation of the principal components was achieved without subjecting factor loads to any rotations. Thus, the components were obtained: f_1 (financial security), f_2 (demographic security), f_3 (social security), f_4 (food security), f_5 (scientific and technical security), f_6 (degree of depreciation of fixed assets), f_7 (industrial safety). The information content coefficients for all principal components are in the range from 0.70 to 0.95; therefore, their composition is significant. The constructed regression model in a standardized form made it possible to determine the impact of the selected generalized factors on the level of economic security of the regions of the Russian Federation.Conclusion. Having a high level of economic security is important for the activities of each region, therefore it is necessary to conduct high-quality monitoring of the degree of economic security, which allows you to identify weaknesses and strengths in the economy. The results of the study made it possible to form the main generalized factors of economic security of the regions: financial, demographic, social, food, scientific and technical, industrial safety and the degree of depreciation of fixed assets - the subjects of the Russian Federation can be assessed from the point of view of their economic stability, and, consequently, their competitiveness at the national level.

Sequential Latin hypercube designs have recently received great attention for computer experiments. Much of the work has been restricted to invariant spaces. The related systematic construction methods are inflexible while algorithmic methods are ineffective for large designs. For such designs in space contraction, systematic construction methods have not been investigated yet. This paper proposes a new method for constructing sequential Latin hypercube designs via good lattice point sets in a variety of experimental spaces. These designs are called sequential good lattice point sets. Moreover, we provide fast and efficient approaches for identifying the (nearly) optimal sequential good lattice point sets under a given criterion. Combining with the linear level permutation technique, we obtain a class of asymptotically optimal sequential Latin hypercube designs in invariant spaces where the $L_1$-distance in each stage is either optimal or asymptotically optimal. Numerical results demonstrate that the sequential good lattice point set has a better space-filling property than the existing sequential Latin hypercube designs in the invariant space. It is also shown that the sequential good lattice point sets have less computational complexity and more adaptability.

The background of the development of the model of economic development of Ukraine in the context of social orientation has been analyzed taking into account the interdependent influence of the mechanism of market relations and economic policy of the state. It is researched that the economic mechanism of socially oriented market economy contains organizational structure of production (vertical and horizontal), specific forms of functioning of economic system (state and non-state regulation of the market), as well as a specific institutional base (including its legislative component). The constituents of the economic system are entities formed by large economic entities (eg financial corporations). The authors argue that the economic mechanism of a socially oriented national economy is a complex structure and system of interconnections and includes: a) a system of balanced markets; b) public sector of economy; c) large economic structures that fulfill the regulatory role of the state for the economy as a whole and at the same time increase the market sensitivity to medium and long-term programs of its development; d) public sector administrative and production subsystem; e) system of operative state regulation of economy; e) a budget-balancing system with a powerful core; g) regulatory framework governing mid-market processes. The study states that Ukraine, in rather difficult conditions, produces the parameters of its own national model of socio-economic development for the long term. The country has not yet formulated or implemented an effective model of economic development that would fully reflect its national characteristics and interests and become a macroeconomic basis for effective state regulation It is determined that in the conditions of construction of a new model of the national economy the role of non-governmental and charitable organizations is increasing. The role of non-governmental organizations, which represent one of the most optimal legal forms to assist citizens in solving their common problems, upholding common interests, is a compulsory attribute of the model of socially oriented national economy.

Connectomics: A new paradigm for understanding brain disease

This paper deals with a MultiAgent System (MAS) and our primary objective is to study how the behavior of the system changes when the interconnections among the agents exhibit non-uniform link weights. Our main contribution is to show when the system with non-uniform coupling strengths is more stable compared to the system with uniform weights. In the process of proving our main idea, we tackle the stability of the system and we propose an approximation method for the computation of the system convergence time.

In this paper, a framework incorporating flexibility as a characteristic is proposed for designing complex, resilient socio-ecological systems. In an interconnected complex system, flexibility allows prompt deployment of resources where they are needed and is crucial for both innovation and robustness. A comparative analysis of flexible manufacturing systems, economics, evolutionary biology, and supply chain management is conducted to identify the most important characteristics of flexibility. Evolutionary biology emphasises overlapping functions and multi-functionality, which allow a system with structurally different elements to perform the same function, enhancing resilience. In economics, marginal cost and marginal expected profit are factors that are considered to be important in incorporating flexibility while making changes to the system. In flexible manufacturing systems, the size of choice sets is important in creating flexibility, as initial actions preserve more options for future actions that will enhance resilience. Given the dynamic nature of flexibility, identifying the characteristics that can lead to flexibility will introduce a crucial dimension to designing resilient and sustainable socio-ecological systems with a long-term perspective in mind.

Mexico is committed to reducing its CO2 emissions according to the Paris Agreement. A relevant effort must be made for the analysis of Mexico's electric energy system towards a progressive decarbonization with a larger participation of intermittent renewable energies. The analysis of power planning scenarios, with different assumptions on costs, emissions, and intermittent performance of the power generating technologies, is needed to make sustainable decisions in the transition toward a cleaner power sector. Tools for energy modelling are required to develop and analyze scenarios with minimum costs subject to environmental constraints. The purpose of the article is to explain the modelling approach of a novel and flexible power planning tool, which is based on a well‐known linear programming optimization method combined with a computing strategy to optimize time consumed for reading, processing calculations, and writing the huge number of economic and technical parameters required for the hourly power dispatch in complex interconnected electric systems. The time consumed has been optimized by means of a binary matrix that activates the input and use of only the data needed for the solution of the problem. The paper describes the MC model and demonstrates some of its analytical capabilities through a Mexican case study with a least cost scenario and two decarbonization scenarios of the power interconnected system for the period from 2020‐2050.

In an interconnected power system network, global performance is affected by various unknown power system parameters subjected to system uncertainties. These unknown parameters in the control expression deteriorate the performance of the power system network. Therefore, these terms associated with the control expression must be estimated precisely. This paper proposes an adaptive backstepping scheme using an entirely coupled recurrent neural network (ECRNN) to estimate these control terms. Three continuous differentiable functions are used to design control input, virtual signals, and adaptive control laws to achieve global performance. The objective of ECRNN is to reduce the control complexity by estimating the associated nonlinear term in the control expression. It will facilitate the complex formulation of the controller and improve system performance. The robust functional estimation ability of ECRNN will make the system immune to uncertainties that may appear due to external disturbances. In ECRNN, feedback loops are added to each neuron layer to achieve additional estimation accuracy. The proposed adaptive law enhances the online weight update speed and accuracy. Verification of the proposed scheme is carried out in MATLAB/Simulink. It is also verified in the real-time digital simulator (RTDS) platform using the IEEE standard New England 39-bus, 10-machine power system model. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —This paper is motivated by the existing limitations in the global performance of a multimachine power system network due to uncertainty in the system parameters. Uncertainties in the power system network primarily appeared due to penetration of renewable power sources, load uncertainty, or occurrence of an uncertain fault in the network. As power system networks are complex nonlinear interconnected systems, these perturbations in the generator states may cause economic losses, load demand uncertainty, or electric scarcity. Thus, a control scheme is required to address the global performance of such networks. This article proposes uniform ultimate bounded stability of synchronous generators in a multimachine power system network with a robust ECRNN-based backstepping control design. The other available technique has not adequately addressed the global performance under uncertainties. The efficacy of the proposed scheme is verified in a real-time environment via a real-time digital simulator which may be a feasible solution for designing excitation control for the synchronous machine in an extensive industrial network.

A Higher Calling: Toward a More Spacious Role for Academic Advisors

Public policy on the development and use of genetically modified organisms (GMOs) has mainly been concerned with defining proper strategies of risk management. However, surveys and focus group interviews show that although lay people are concerned with risks, they also emphasize that genetic modification is ethically questionable in itself. Many people feel that this technology "tampers with nature" in an unacceptable manner. This is often identified as an objection to the crossing of species borders in producing transgenic organisms. Most scientists reject these opinions as based on insufficient knowledge about biotechnology, the concept of species, and nature in general. Some recent projects of genetic modification aim to accommodate the above mentioned concerns by altering the expression of endogenous genes rather than introducing genes from other species. There can be good scientific reasons for this approach, in addition to strategic reasons related to greater public acceptability. But are there also moral reasons for choosing intragenic rather than transgenic modification? I suggest three interrelated moral reasons for giving priority to intragenic modification. First, we should respect the opinions of lay people even when their view is contrary to scientific consensus; they express an alternative world-view, not scientific ignorance. Second, staying within species borders by strengthening endogenous traits reduces the risks and scientific uncertainty. Third, we should show respect for nature as a complex system of laws and interconnections that we cannot fully control. The main moral reason for intragenic modification, in our view, is the need to respect the "otherness" of nature.

In general, energy infrastructure is a basic but very complex system of elements, interconnections, functional inputs and outputs, which creates the need to break down subsystems, systems, and infrastructure areas. The aim of this chapter is therefore to discuss the possible implementation of approaches to risk assessment and risk management in relation to the application of technical security measures. This chapter of the book will therefore discuss risk analysis methods where the transition from general approaches to risk analysis, through risk identification methods and procedures and the assessment of major industrial and technological risks, to specific risk analysis methodologies for electricity infrastructures, will be presented. An important part of the chapter is also the introduction of practical approaches and methodologies that are accepted as “best practices” in connection with ensuring the technical security of electricity infrastructures.