State Of System Research Articles

Cardiorespiratory system of massage therapists when performing a dosed massage procedure

The article tells about the presentation of a number of studies on the effect of massage procedures on the physiological, biochemical and psychological status of a person, while work on evaluating the functional indicators of massage therapists during the procedure is rare. The study aims to determine the functional state of the cardiorespiratory system (CRS) of massage specialists in the dynamics of performing a 30-minute back massage session. The object of the study was 10 male massage therapists (age 36.0 (29.0;42.0); BMI 24.7(23.3;31.3). The study consisted in performing a classical back massage procedure for 30 minutes according to a generally accepted technique using six massage techniques. To determine the functional state during the work of specialists, an ergospirometric system and measurement of blood pressure (BP) by the Korotkiy method were used. During the massage procedure, specialists noted an increase in metabolic parameters, oxygen consumption (OC), respiratory coefficient (RC) and energy consumption, as well as blood pressure by the 30th minute of the procedure. When performing a 30-minute back massage, massage specialists significantly mobilize the links of the cardiorespiratory system. At the end of the procedure, there is an increase in blood pressure. However, the maximum increase in the parameters of the cardiorespiratory system occurs when performing a shock vibration reception. Limitations. Due to the small sample of the group, it is not possible to statistically reliably assess the significance of changes in some indicators. Ethics. The protocol of the experiment corresponded to the Helsinki Declaration. The study was developed and conducted in accordance with the methodological guidelines of the Local Scientific Research Committee on Bioethics of the Institute of Physiology of the Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences.

High temperature condensation and many body localization of blended ferrons in antiferromagnetic clusters

Abstract This paper presents a multiferron system and analyzes the conditions under which it forms a localized many-body state. We determined the self-trapping potential of this system and showed that the ferrons pair up to form bound biferron states, which interact through their relative spin cloud and settle into two different configurations mimicking the Bose-Einstein Condensate (BEC) and Bardeen-Cooper-Schrieffer (BCS) states. The external B-field strengthens the magnetic coupling, which favors the pairing of the ferrons. It also creates a vortex, providing good confinement of the particles and favoring condensation. The system's state functions are well described by the nonlinear Schr"{o}dinger equation, whose solution is a bell-shaped soliton representing the density of particle distribution in the condensate. The system's critical temperature is obtained as a function of the biferron energy shift and thus strongly depends on the applied field.

Time/Event‐Triggered Exponential Stabilization for Stochastic Systems: Enhancing Nonlinearity Tolerance

ABSTRACTThis article seeks the enhancement of nonlinearity tolerance in time/event‐triggered stabilization for stochastic systems. In the related results, the controller functions are required to obey global Lipschitz condition for the suppression of sampling/execution error, and the drift and/or diffusion coefficients of the stochastic systems are restricted to polynomial or, even, linear growth. These limitations deserve overcoming for enlarged applications. To this end, a distinct framework of time/event‐triggered controls is established for stochastic systems, targeted at exponential stabilization. Specifically, inclusive Lyapunov‐type feasibility conditions are proposed by capturing the effect of sampling/execution error and distinguishing the role of system nonlinearities. Particularly, different from the related results, the evolution of sampling/execution error is subtly exploited via Lyapunov functions to reveal the dynamic interaction between the sampling/execution errors and system state. Then, time‐triggered exponential stabilization via sampled‐data controller is achieved not only in the moment sense but also in the almost sure sense. Accordingly, Lyapunov function based analysis is performed for the composite dynamics of system state and sampling error, confronted with the coupling of discontinuous and stochastic features. To further reduce execution, periodic event‐triggered control is exploited to achieve exponential stabilization for stochastic nonlinear systems, by virtue of the relation with the dynamic evolution under sampled‐data control. Through typical examples, we demonstrate the potential of our framework in handling the cases with the controller functions violating global Lipschitz condition and with the system nonlinearities beyond polynomial growth.

Fluid Interaction Analysis for Rotor-Stator Contact in Response to Fluid Motion and Viscosity Effect

Fluid–structure interaction introduces critical failure modes due to varying stiffness and changing contact states in rotor-stator systems. This is further aggravated by stress fluctuations due to shaft impact with a fixed stator when the shaft rotates. In this paper, the investigation of imbalance and rotor-stator contact on a rotating shaft was carried out in viscous fluid. The shaft was modelled as a vertical elastic rotor system based on a vertically oriented elastic rotor operating in an incompressible medium. Implicit representation of the rotating system including the rotor-stator contact and the hydrodynamic resistance was formulated for the coupled system using the energy principle and the Navier–Stokes equations. Additionally, the monolithic approach included an implicit strategy of the rotor-stator fluid interaction interface conditions in the solution methodology. Advanced time-frequency methods, such as Hilbert transform, continuous wavelet transform, and estimated instantaneous frequency maps, were applied to extract the vibration features of the dynamic response of the faulted rotor. Time-varying stiffness due to friction is thought to be the main reason for the frequency fluctuation, as indicated by historical records of the vibration displacement, whirling orbit patterns of the centre shaft, and the amplitude–frequency curve. It has also been demonstrated that the augmented mass associated with the rotor and stator decreases the natural frequencies, while the amplitude signal remains relatively constant. This behaviour indicates a quasi-steady-state oscillatory condition, which minimises the energy fluctuations caused by viscous effects.

State of thermophylic ichthyofauna in the water bodies of Arkhangelsk Oblast: Report 2. Biological characteristics of fish

The biological characteristics of warm-water fish species living in water bodies of the Arkhangelsk region are presented. Changes in size and mass parameters, age and sex structures and reproductive ability of the Severodvinsk sterlet in the temporal aspect were revealed. It has been established that it has good growth rates, a reserve in replenishing the spawning stock and a stable state of the natural reproduction system. The biological parameters of blue bream and rudd, rare species of fish that live in the lakes of the Kenozersky National Park, as well as a number of reservoirs in the Arkhangelsk region, were obtained. The biological characteristics of species that appeared in the river basin are considered. Northern Dvina as a result of self-dispersal - white-eye and asp, as well as the nutrition and feeding relationships of white-eye with native fish species. The attention of specialists to these alien fish species is due to the need to develop an environmental forecast for the development of the situation with their numbers in the context of ongoing global warming.

Деінституціоналізація корпоратизму в радянській економіці та її наслідки для економіки сучасної України

The article is devoted to the study of the Soviet period of Ukraine’s economy, in particular the transformation of institutions in the absence of Ukrainian statehood. The subject of the study is corporatism as a mechanism for coordinating and implementing the interests of the state, society and business in different economic systems: the command-administrative and market ones. The aim of the article is to identify the main factors of the deinstitutionalization of corporatism in the Soviet economy and to clarify their impact on the modern economy of Ukraine. General scientific methods of interdisciplinary research, analysis and synthesis, induction and deduction and a systemic approach are used in generalizing economic trends and determining cause-and-effect relationships. It is argued that the ideology of Bolshevism was the basis for changing the economic system, on whose basis the transformation of economic institutions in the command-administrative economy was carried out. The author reveals the content and mechanisms of the nationalization of the economy, the degeneration of formal institutions of corporatism and their use to restrict economic freedom and suppress civil society, which contradicts the very idea of corporatism as a union of equals. The importance of excluding national interests from economic consciousness and practice is emphasized, as evidenced in particular by the inefficiency of the allocation and use of Ukraine's productive resources. The article established the consequences of the deinstitutionalization of corporatism in the Soviet period for the economy of modern Ukraine, namely: high concentration of property, monopolism, the inability of large industry to self-sustainable development, the lack of concentration of capital in high-tech industries, and the lack of social partnership. The conclusion is made about the replacement of corporatism by bureaucratic corporatism in the Soviet period of Ukrainian history and its further transformation into oligarchic corporatism in the 90s of the 20th century.

Fixed‐Time Consensus Control With Event‐Triggered Mechanism for Multi‐Agent Systems Suffered Time‐Varying State Constraints

ABSTRACTA fixed‐time consensus control protocol is proposed for uncertain nonlinear multi‐agent systems (MASs) with time‐varying state constraints. By applying the time‐varying barrier Lyapunov functions (BLFs), an adaptive consensus control protocol is constructed to make certain that all system states maintain within the predetermined time‐varying ranges. Meanwhile, an event‐triggered mechanism (ETM) is established to alleviate the burden of MASs communication. Besides, to guarantee the control performance, a fixed‐time control method based on neural networks (NNs) is developed. It is demonstrated that the MASs can synchronize in a fixed time, and the state constraints are satisfied. Finally, two simulation examples demonstrate the effectiveness of the presented protocol.

Full-state-constrained intelligent adaptive control for nonlinear systems with unmodeled dynamics and mismatched disturbances

Abstract This paper develops a novel full-state-constrained intelligent adaptive control (FIAC) scheme for a class of uncertain nonlinear systems under full state constraints, unmodeled dynamics and external disturbances. The key point of the proposed scheme is to appropriately suppress and compensate for unmodeled dynamics that are coupled with other states of the system under the conditions of various disturbances and full state constraints. Firstly, to guarantee that the time-varying asymmetric full state constraints are obeyed, a simple and valid nonlinear error transformation method has been proposed, which can simplify the constrained control problem of the system states into a bounded control problem of the transformed states. Secondly, considering the coupling relationship between the unmodeled dynamics and other states of the controlled system such as system states and control inputs, a decoupling approach for coupling uncertainties is introduced. Thereafter, owing to the employed dynamic signal and bias radial basis function neural network (BIAS-RBFNN) improved on traditional RBFNN, the adverse effects of unmodeled dynamics on the controlled system can be suppressed appropriately. Furthermore, the matched and mismatched disturbances are reasonably estimated and circumvented by a mathematical inequality and a disturbance observer, respectively. Finally, numerical simulations are provided to demonstrate the effectiveness of the proposed FIAC strategy.

Ultrafast optical induction of magnetic order at a quantum critical point

Time-resolved ultrafast spectroscopy has emerged as a promising tool to dynamically induce and manipulate non-trivial electronic states of matter out-of-equilibrium. Here we theoretically investigate light pulse driven dynamics in a Kondo lattice system close to quantum criticality. Based on a time-dependent auxiliary fermion mean-field calculation we show that light can dehybridize the local Kondo screening and induce oscillating magnetic order out of a previously paramagnetic state. Depending on the laser pulse field amplitude and frequency the Kondo singlet can be completely deconfined, inducing a dynamic Lifshitz transition that changes the Fermi surface topology. These phenomena can be identified in harmonic generation and time-resolved angle-resolved photoemission spectroscopy spectra. Our results shed new light on non-equilibrium states in heavy fermion systems.

It's the workforce, stupid!

If noted political campaign advisor James Carville were to review the current state of the addiction care system, I am confident that he would identify the biggest problem facing this system as the inability to recruit and retain a workforce. I also believe that he would advise those who make drug policy to focus on workforce issues and not shift the focus to anything else before a plan is in place and working.

Experimental Study of Animal’s Behavior under the Influence of an Electromagnetic Field of the 5G Mobile Communication Standard

A pilot experimental study was carried out to assess the effect of an unmodulated and modulated electromagnetic field of the 5G mobile communication standard on the central nervous system of animals. Mature male Wistar rats were exposed to electromagnetic fields with a frequency of 4.9 GHz and an intensity of 250 MW/cm2 for 15 days for 2 hours a day. The animals of the two irradiated groups and the control group were in identical conditions in a semi-anechoic shielded chamber. The effect of the electromagnetic field on the functional state of the central nervous system was assessed by a comprehensive analysis of behavior patterns in the “open field” test before and after irradiation. The study did not reveal clear differences in animal behavior when exposed to an unmodulated and modulated 5G electromagnetic field. Statistically significant changes in animal behavior were recorded in the dynamics of the experiment in two irradiated and control groups, which may be due to a change in the natural electromagnetic background in a semi-anechoic shielded chamber.

Experimental Study of Stress Reactions Induced by Low-Intensity Microwave Radiation

A study was made of the severity and dynamics of changes in indicators reflecting the state of the blood system (the number of myelokaryocytes in the femur, the level of CFU-S in the exo and endotest, hemolytic resistance of erythrocytes, as well as the mass and cellularity of the thymus) in mice exposed to monochromatic pulsed electromagnetic fields of the frequency range 2.27–2.78 GHz with an average power flux density of 60 μW/cm2 at doses from 0.086 to 0.86 J/g. It is shown that under repeated exposure to electromagnetic fields, the bioeffect cumulates, leading to the development of a stress-like adaptive reaction in animals.

Decentralized Finite‐Time Adaptive Neural Output‐Feedback Quantized Control for Switched Nonlinear Large‐Scale Delayed Systems

ABSTRACTThis paper considers the problem of decentralized finite‐time adaptive neural output‐feedback quantized control for a class of switched nonlinear large‐scale delayed systems. A switched high‐gain quantized state observer is therefore constructed for each subsystem to estimate unavailable system states. Different from the traditional Lyapunov–Krasovskii functional method, multiple Lyapunov–Krasovskii functions are introduced to develop the decentralized adaptive output‐feedback control strategy with neural network approximation for the switched nonlinear large‐scale delayed systems. Under a category of switching signals with persistent dwell time, all signals in the closed‐loop switched system are semi‐globally uniformly ultimate bounded. Meanwhile, the tracking errors can remain in a small domain of origin in finite time. Case studies are finally used to illustrate the flexibility and effectiveness of the proposed control approach, including the switched two continuous stirred tank reactor delayed systems.

ON THE GAUSSIAN CURVATURE FUNCTIONAL IN THE CLASS OF SURFACES OF POSITIVE GAUSSIAN CURVATURE

The paper establishes the form of the Gaussian curvature functional defined on the class of infinitely differentiable horizontal surfaces of positive Gaussian curvature. With respect to admissible surfaces, it is assumed that they admit a global semi-geodetic parametrization. The paper proves that the first variation of the functional on the class of variations of admissible surfaces admitting connections between the coefficients of the first quadratic form and their geodesic lines similar to the axisymmetric case is determined by the Gaussian curvature of the varied surface. The considerations of the type are closely connected with the problems of the study of the equilibrium forms having one of the main curvatures sufficiently small. In this case, the classical Laplace formula fails. Thus, there appear a necessity to take into account more subtle processes leading to the adequate description of the equilibrium state of the two-phased system. In particular, it is quite natural to introduce into the study an intermediate layer consisting of the molecules of the two different phases, one of the Maxwell’s ideas. The calculations of the work spended by the pressure forces for the formation of intermediate layer leads us to the necessity to introduce Gauss functional into consideration. Linear combination of mean curvature and gaussian curvature functionals gives possibility to construct variational solution of generalized Laplace equation.

Features of Wetting with Water Hydrophobic Powders of Methyl Silica and Composite Systems Based on it.

The phase state of heterogeneous systems prepared on the basis of mixtures of hydrophobic and hydrophilic silica and water, depending on the ratio of component concentrations, and their using as thixotropic agents has been studied. It was found that the dependence of the interfacial energy of water with the surface of the particles of the composite system made on the basis of hydrophilic and hydrophobic silica taken in the proportion of 1:1 as for the individually taken AM-1 has a bell-shaped form with peaks at h=3 and 1.5 g/g, respectively. The type of dependence is due to the complex processes involved in the formation of the composite system involving solid particles, water, and air.

Design of shortcuts to adiabaticity for Bose–Einstein condensate dynamics in soliton Josephson junctions

This article primarily establishes a two-soliton system and employs the Lewis–Riesenfeld invariant inverse control method to achieve shortcuts to adiabaticity (STA) technology. We study an atomic soliton Josephson junctions (SJJs) device and subsequently compare and analyze it with atomic bosonic Josephson junctions. Moreover, we use higher-order expressions of the auxiliary equations to optimize the results and weaken the detrimental effect of the sloshing amplitude. We find that in the adiabatic shortcut evolution of two systems with time-containing tunnelling rates, the SJJs system is more robust over a rather short time evolution. In comparison with linear ramping, the STA technique is easier to achieve with the precise modulation of the quantum state in the SJJs system.

Clinical experience in the study of thrombodynamics in pregnant women at risk of developing preeclampsia and during its manifestation

BACKGROUND: Need for early diagnosis of intravascular activation of coagulation in obstetric patients at risk of preeclampsia. AIM: The aim of this study was to assess the diagnostic value of the thrombodynamics test in patients at risk of developing preeclampsia and during its manifestation. MATERIALS AND METHODS: Dynamic thrombophotometry was performed in 56 pregnant women using a domestic “T2 Thrombodynamics Recorder” device (GemaKor Ltd., Russia). The first study group consisted of patients in the second to early third trimester of pregnancy (n = 45), who, due to hypercoagulability, according to the conventional coagulogram, received low-molecular-weight heparin therapy (calcium nadroparin 0.3 ml or enoxaparin sodium 0.4 ml subcutaneously). The thrombodynamics test was performed to evaluate the efficacy of anticoagulant therapy. The second study group involved patients with moderate (n = 11) and severe (n = 8) preeclampsia. RESULTS: The test was effective in monitoring the state of the hemostasis system in pregnant women receiving anticoagulant therapy — despite normal coagulogram test parameters, the increased rate of fibrin clot formation and / or spontaneous clots indicated increased anticoagulant therapy in 37.8% of patients. Among patients with extragenital pathology, the incidence of spontaneous clots, which should not form during normal coagulation, was observed in all pregnant women with chronic arterial hypertension combined with obesity (χ2 = 6.11; p 0.02), which characterizes the tendency to activate intravascular coagulation in such patients. Subsequently, moderate PE developed in 15.6% of pregnant women with predisposing extragenital pathology, there being no cases of severe preeclampsia. A comparison of thrombodynamics test parameters in patients with moderate and severe preeclampsia showed that in severe preeclampsia, there is a tendency to a higher rate of fibrin clot formation and a higher frequency of spontaneous clot formation (χ2 = 12.7; p 0.01). The test demonstrated high sensitivity (81.8%) and specificity (97.4%) of signaling the presence of severe preeclampsia. CONCLUSIONS: Demonstration of a clinical case of HELLP syndrome in a pregnant woman showed that confirmation of consumption thrombocytopenia due to activation of intravascular coagulation using the thrombodynamics test, in contrast to the global thromboelastography test and the conventional coagulogram test, allowed timely initiation of anticoagulant therapy and avoided the development of irreversible secondary microangiopathy.

Potential energy landscape formalism for quantum molecular liquids

The potential energy landscape (PEL) formalism is a powerful tool within statistical mechanics to study the thermodynamic properties of classical low-temperature liquids and glasses. Recently, the PEL formalism has been extended to liquids/glasses that obey quantum mechanics, but applications have been limited to atomistic model liquids. In this work, we extend the PEL formalism to liquid/glassy water using path-integral molecular dynamics (PIMD) simulations, where nuclear quantum effects (NQE) are included. Our PIMD simulations, based on the q-TIP4P/F water model, show that the PEL of quantum water is both Gaussian and anharmonic. Importantly, the ring-polymers associated to the O/H atoms in the PIMD simulations, collapse at the local minima of the PEL (inherent structures, IS) for both liquid and glassy states. This allows us to calculate, analytically, the IS vibrational density of states (IS-VDOS) of the ring-polymer system using the IS-VDOS of classical water (obtained from classical MD simulations). The role of NQE on the structural properties of liquid/glassy water at various pressures are discussed in detail. Overall, our results demonstrate that the PEL formalism can effectively describe the behavior of molecular liquids at low temperatures and in the glass states, regardless of whether the liquid/glass obeys classical or quantum mechanics.

State estimation of magnetorheological suspension of all-terrain vehicle based on a novel adaptive Sage–Husa Kalman filtering

Abstract For the magnetorheological (MR) suspension control system of all-terrain vehicles (ATVs), state estimation is an effective method to obtain system feedback signals that cannot be directly measured by sensors. However, when confronted with modeling errors and sudden changes in sensor noise during complex road driving, conventional estimation methods with fixed parameters encounter challenges in accurately estimating the states of ATV suspension system. To address this issue, this paper introduces a novel adaptive Sage-Husa Kalman filter (ASHKF) algorithm to estimate the sprung and unsprung velocity of ATV suspension system. The algorithm uses exponential weighting function and gradient detection function to adaptively adjust the attenuation coefficient according to the driving conditions of the ATV, thereby realizing real-time correction of the covariance matrix of the prediction error. Ultimately, through simulation and real-vehicle testing, it is demonstrated that the designed ASHKF is able to effectively improve the state estimation accuracy of the speed signal of the suspension system under off-road driving conditions with low-frequency noise and outlying disturbances, and the accuracy is improved by 62.70% compared with that of the conventional Sage-Husa Kalman filter (SHKF).

A robust distributed interaction multiple model filter for jump Markov systems with heavy-tailed measurement noise

When heavy-tailed measurement noises (HTMNs) are introduced by outliers, the estimation accuracy of traditional distributed interaction multiple model (IMM) algorithms will be severely reduced in some target tracking scenarios. To solve the problem, a new distributed robust filter algorithm using cubature information filtering and weighted average consensus approach in the framework of IMM filtering is proposed. Firstly, the HTMNs are modeled as Student’s t-distributions, and as conjugate prior distributions for the degree of freedom parameters and the scale matrices, the Gamma distributions and the inverse-Wishart distributions have been chosen. Secondly, the system state vectors, noise corresponding parameters, and model probabilities are inferred utilizing the variational Bayesian method. What’s more, in order to increase the stability of sensor networks and improve the estimation accuracy of the proposed filtering algorithm, the weighted average consensus approach is used to update information pairs and model probabilities. Finally, a target tracking simulation experiment is used to verify that the proposed algorithm has higher estimation accuracy and robustness than existing advanced filtering algorithms in dealing with HTMN.