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Homogeneous liquid‐phase oxidation of a number of aromatic and aliphatic olefins was examined using dinuclear anionic vanadium dioxido complexes [(VO2)2(salLH)]− (1) and [(VO2)2(NsalLH)]− (2) and dinuclear copper complexes [(CuCl)2(salLH)]− (3) and [(CuCl)2(NsalLH)]− (4) (reaction of carbohydrazide with salicylaldehyde and 4‐diethylamino salicylaldehyde afforded Schiff‐base ligands [salLH4] and [NsalLH4], respectively). Anionic vanadium and copper complexes 1, 2, 3, and 4 were isolated in the form of their hydronium ion salt, which is rare. The molecular structure of the hydronium ion salt of anionic dinuclear vanadium dioxido complex [(VO2)2(salLH)]− (1) was established through single‐crystal X‐ray analysis. The chemical and structural properties were studied using Fourier transform infrared (FT‐IR), ultraviolet–visible (UV–Vis), 1H and 13C nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI‐MS), electron paramagnetic resonance (EPR) spectroscopy, and thermogravimetric analysis (TGA). In the presence of hydrogen peroxide, both dinuclear vanadium dioxido complexes were applied for the oxidation of a series of aromatic and aliphatic alkenes. High catalytic activity and efficiency were achieved using catalysts 1 and 2 in the oxidation of olefins. Alkenes with electron‐donating groups make the oxidation processes easy. Thus, in general, aromatic olefins show better substrate conversion in comparison to the aliphatic olefins. Under optimized reaction conditions, both copper catalysts 3 and 4 fail to compete with the activity shown by their vanadium counterparts. Irrespective of olefins, metal (vanadium or copper) complexes of the ligand [salLH4] (I) show better substrate conversion(%) compared with the metal complexes of the ligand [NsalLH4] (II). [ABSTRACT FROM AUTHOR]

We propose a control method for dynamical systems that permits one to guarantee that the plant output signal is in a given set at any time. To solve the problem, a special change of coordinates is used that permits one to reduce the original problem with constraints to the problem of studying the input–state stability of the new extended unconstrained system. Examples of coordinate changes are given, and control algorithms for linear plants and systems with a sector nonlinearity in the presence of parametric uncertainty and disturbances are synthesized. The results obtained are accompanied by modeling that illustrates the efficiency of our method and confirms the theoretical conclusions. [ABSTRACT FROM AUTHOR]

In this survey, we discuss various approaches to control theory that have arisen in the recent decades and reflect the desire to reach a trade-off between the -control theory and the -control theory. The theories of the kind include the theory of risk-sensitive controllers, the theory of suboptimal control with a constraint on the -entropy functional, the mixed -control theory, the minimax -control theory, the anisotropy-based theory, and some others. The survey discusses in more detail the anisotropy-based control theory, which includes both the - and the -theory within a single statement of the problem. [ABSTRACT FROM AUTHOR]

This paper provides an analysis of the current state-of-the-art technologies in the field of auto-operators used in production during the electroplating process. General schemes of operations are presented, benefits and drawbacks of each scheme are discussed. The paper discusses an increase in the operating efficiency of the auto-operator in transient conditions (braking and acceleration) by reducing suspension oscillations and provides an example of a similar problem from other industries. In addition to the classification of the auto-operators, three main ways and control methods of the auto-operator of a galvanic line are presented. The main ways of eliminating oscillations during the movement of the auto-operator, as well as the rationale for the choice of adaptive (optimal) control, based on and comparing the basic control algorithms of the robot manipulator, are discussed. The comparative analysis of algorithms used to determine the optimal control has been carried out. Application field of each optimal control method described, moreover advantages and disadvantages as well as implementation methods described. Bellman dynamic programming method was chosen to eliminate oscillations of the suspension with details during the auto-operator transient conditions, the chosen method takes into account all necessary conditions to achieve the desired result. [ABSTRACT FROM AUTHOR]

Innate antiviral immunity is the first line of host defense against invading viral pathogens. Immunity activation primarily relies on the recognition of pathogen‐associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs). Viral proteins or nucleic acids mainly engage three classes of PRRs: Toll‐like receptors (TLRs), retinoic acid‐inducible gene I (RIG‐I)‐like receptors (RLRs), and DNA sensor cyclic GMP‐AMP (cGAMP) synthase (cGAS). These receptors initiate a series of signaling cascades that lead to the production of proinflammatory cytokines and type I interferon (IFN‐I) in response to viral infection. This system requires precise regulation to avoid aberrant activation. Emerging evidence has unveiled the crucial roles that the ubiquitin system, especially deubiquitinating enzymes (DUBs), play in controlling immune responses. In this review, an overview of the most current findings on the function of DUBs in the innate antiviral immune pathways is provided. Insights into the role of viral DUBs in counteracting host immune responses are also provided. Furthermore, the prospects and challenges of utilizing DUBs as therapeutic targets for infectious diseases are discussed. [ABSTRACT FROM AUTHOR]

A novel electrochemical esterification of alkynes for the synthesis of esters was developed in which diols and their derivatives were used as the partners. This method is green as it is catalyst-free, oxidant-free, and additive-free and shows atom-economy. This is the first example of an electrochemical reaction via cleavage of carbon–carbon triple bonds. Meanwhile, this is also the first example of a carbon–carbon triple bond cleavage reaction of alkynes with diols. [ABSTRACT FROM AUTHOR]

A practically significant effect of a surge occurrences in linear dynamical systems under nonzero initial conditions is explored. The linear dynamical system subjected to unknown-but-bounded exogenous disturbances is considered. Using the apparatus of linear matrix inequalities and the invariant ellipsoids concept, the estimations of the upper bounds of the trajectories deviations are obtained, and an approach is suggested to the feedback design that minimizes the deviations. The efficacy of the approach proposed is illustrated on numerical examples. [ABSTRACT FROM AUTHOR]

The survey is devoted to an exposition of the history of development and the current state of theoretical methods for constructing disturbance observers, whose appearance in control theory and practice dates back to the middle of the 1960s and is associated with the expansion of algebraic methods in controller synthesis, the emergence of computer-based synthesis procedures, the need to solve more and more complex problems, and the desire to optimize the control process. The survey describes observers of harmonic disturbances, outlines the internal model principle, considers observers of bounded disturbances, and describes methods for estimating disturbances using auxiliary filters in the form of transfer functions and state observers. [ABSTRACT FROM AUTHOR]

The DIRECT method solves Lipschitz global optimization problems on a hyperinterval with an unlimited range of Lipschitz constants. We propose an extension of the DIRECT method principles to problems with multiextremal constraints is proposed when two evaluations of functions at the ends of the chosen main diagonals are used at once. We present computational illustrations, including the solution of a problem with discontinuities. We also perform convergence analysis. [ABSTRACT FROM AUTHOR]

Linear continuous or discrete time-varying systems in which the sum of a quadratic form of the initial state and the integral or sum of quadratic forms of a disturbance on a finite horizon is bounded above by a given value are considered. It is demonstrated that the reachability set of such a continuous- or discrete-time system is an evolving ellipsoid, and its ellipsoid matrix satisfies a linear matrix differential or difference equation, respectively. The optimal ellipsoidal observer and identification algorithm that yield the best ellipsoidal estimates of the system's state and unknown parameters are designed. In addition, the optimal controllers ensuring that the system's state will fall into a target set or that the system's trajectory will stay within the ellipsoidal tube are designed. A connection between the optimal ellipsoidal observer and the Kalman filter is established. Some illustrative examples for the Mathieu equation, which describes the parametric oscillations of a linear oscillator, are given. [ABSTRACT FROM AUTHOR]

This paper considers a linear continuous-discrete time-varying system described by a set of differential and difference equations on a finite horizon. For such a hybrid system, the concept of the generalized H 2 norm is introduced, representing the induced norm of a linear operator generated by the system under consideration. This norm is characterized in terms of Lyapunov difference equations and also in terms of recursive linear matrix inequalities. Discrete time-varying optimal controllers, including multiobjective ones, that minimize the generalized H 2 norm of the closed loop system are designed. [ABSTRACT FROM AUTHOR]

The properties of the set of trajectories of the control system described by Urysohn type integral equation are considered. It is assumed that the system is affine with respect to the control vector and control functions are chosen from the bounded and closed ball of the space L q (E ; R m) , q>1. The trajectory of the system is the function from the space L p (E ; R n) , 1 / q + 1 / p = 1 , which satisfies the system's equation almost everywhere. The path-connectedness and compactness of the set of trajectories are proved. The existence of the optimal trajectories in the optimal control problem with lower semicontinuous payoff functional is discussed. [ABSTRACT FROM AUTHOR]

A novel multi-objective robust control problem is studied for systems with norm-bounded structured uncertainty and robust generalised H 2 norms as criteria. Necessary conditions for Pareto optimality are formulated from which it follows that Pareto optimal solutions are to be among optimal solutions for scalar multi-objective costs in the form of Germeyer convolution. The upper bounds of the multi-objective costs are used to compute Pareto suboptimal controllers in terms of linear matrix inequalities, while the lower bounds to estimate a 'difference' between Pareto suboptimal and unavailable Pareto optimal controllers. Two-criteria robust control problem for a mathematical model of the rotor rotating in active magnetic bearings is considered as an application of this theory. [ABSTRACT FROM AUTHOR]

The synthesis of cyclic dithiocarbonates via photo‐difunctionalization of the C–C double bond of styrene and aryl aldehydes via photo‐oxidative cleavage of the C–C double bond of styrene was accomplished in the presence of CdS NPs at room temperature in air atmosphere under visible light irradiation without using any external oxidant. Some of the special advantages of these processes are the use of CdS NPs as a simple, accessible, safe, and visible‐light‐induced reusable catalyst, as well as the use of air as an easily attainable, inexpensive, and harmless oxidant, styrene as a readily accessible substrate, and visible‐light as a renewable and safe energy source. [ABSTRACT FROM AUTHOR]

We consider a linear regression model with a vector of bounded parameters and a centered noise vector that has an uncertain unimodal distribution but known covariance matrix. We pose the minimax estimation problem for a linear combination of unknown parameters with the use of the probability criterion. The minimax estimate is determined as a result of minimizing a probability bound over the region of possible values of the variance and squared bias for all possible linear estimates. We establish that the resulting robust solution is less conservative in comparison with wider classes of distributions. [ABSTRACT FROM AUTHOR]

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The design problems of robust static controllers for discrete-time systems with norm-bounded parametric uncertainties and random input disturbances are considered. The controllers under consideration stabilize the plant for all possible values of uncertainty from a given set of parameters and also guarantee a desired suppression level for random exogenous disturbances. A numerical example is given. [ABSTRACT FROM AUTHOR]

A Lewis acid-catalyzed insertion of unsymmetrical alkynes into electron-deficient alkenes was developed for the first time, and used to produce 34 hitherto unreported pentacyclic benzo[5,6]chromeno[2,3-b]indoles with generally good yields and complete stereoselectivity. A Yb(OTf)3-catalyzed reaction between o-alkynylnaphthols and 3-methyleneindolin-2-ones proceeded efficiently, and provided a simple and convergent protocol for alkyne difunctionalization via oxidant-free C–C double bond breaking/rearrangement. Mechanistic details of this domino process were derived by conducting systematic theoretical calculations. [ABSTRACT FROM AUTHOR]

We study the problem of stabilizing multiple-input switched linear systems that may have operation modes of different dynamic orders. To solve this problem, we propose two approaches to constructing a. stabilizing controller based on the dynamic-order extension method and on solving a. system of linear matrix inequalities. [ABSTRACT FROM AUTHOR]

Nonautonomous discrete-time control systems with uncertain nonlinearities and bounded external disturbances are considered. Based on the method of matrix comparison systems and the technique of difference linear matrix inequalities, an approach to solve the problems of state estimation, finite time boundedness with respect to given sets, the suppression of initial deviations and uncertain disturbances using a linear state feedback controller is developed. A method to design a controller with variable coefficients that guarantees the transition from one given ellipsoid to another under any disturbances bounded by the L∞ norm is proposed. [ABSTRACT FROM AUTHOR]

The tumor suppressor p53 is the most frequently mutated gene in human cancer and more than half of cancers contain p53 mutations. The development of novel and effective therapeutic strategies for p53 mutant cancer therapy is a big challenge and highly desirable. Ubiquitin-specific protease 7 (USP7), also known as HAUSP, is a deubiquitinating enzyme and proposed to stabilize the oncogenic E3 ubiquitin ligase MDM2 that promotes the proteosomal degradation of p53. Herein, we report the design and characterization of U7D-1 as the first selective USP7-degrading Proteolysis Targeting Chimera (PROTAC). U7D-1 showed selective and effective USP7 degradation, and maintained potent cell growth inhibition in p53 mutant cancer cells, with USP7 inhibitor showing no activity. These data clearly demonstrated the practicality and importance of PROTAC as a preliminary chemical tool for investigating USP7 protein functions and a promising method for potential p53 mutant cancer therapy., (© 2022 Wiley-VCH GmbH.)

The classical linear quadratic regulation problem is considered in the robust formulations where the matrices of the system and/or initial conditions are not know precisely. Several approaches are proposed where the quadratic cost is minimized against the worst-case uncertainties. Finding such controllers is performed via reducing the matrix Riccati equation with uncertainty to a single linear matrix inequality. The properties of the solutions are discussed and the comparison with previously known approaches is performed. [ABSTRACT FROM AUTHOR]

A technique of multiobjective robust controller synthesis for an electro-optical device line-of-sight stabilization system with saturating actuators is developed on the basis of polytopic linear parameter-varying system theory. From the computational point of view, the synthesis procedure is reduced to convex optimization under constraints expressed in the form of linear matrix inequalities. The multiobjective synthesis of the robust control law for the stabilization system being considered is performed. [ABSTRACT FROM AUTHOR]

The behavior of trajectories of multidimensional linear discrete-time systems with nonzero initial conditions is considered in two cases as follows. The first case is the systems with infinite degree of stability (the processes of a finite duration); the second case is the stable systems with a spectral radius close to 1. It is demonstrated that in both cases, large deviations of the trajectories from the equilibrium may occur. These results are applied to accelerated unconstrained optimization methods (such as the Heavy-ball method) for explaining the nonmonotonic behavior of the methods, which is observed in practice. [ABSTRACT FROM AUTHOR]

Our paper examines the rise of a new category of professional support staff whom we refer to as 'audit-market intermediaries' in the context of a rapidly changing regulatory and funding environment in British higher education. We explore the roles they play in articulating environmental changes in research-intensive universities related to the auditing of teaching via demands for quality assurance and the marketisation of higher education via the rise of the student as a fee-paying consumer. The qualitative data reveals the internal and external sources of legitimacy and power of the audit-market intermediaries as well their contestation. We show how these actors serve as mediators of audit and market forces undertaking institutional work by translating, amplifying or buffering-related pressures within the university; and point at the relevance of the specific organisational context for understanding differing patterns of their institutional work. [ABSTRACT FROM AUTHOR]

Proliferating claims have been made for Learning Outcomes (LOs) potential to re-shape higher education: as forces for transparency and harmonisation, new forms for measurement or a format that fundamentally challenges traditional teaching and learning. Evidence of their actual influence remains sparse, however. This analysis of 45 interviews with university teachers, students and leaders from England and Norway investigates their experiences of LOs. The results suggest LOs are received as an ambiguous policy object, resulting in varied interpretations and uses. However, two persistent tendencies emerge. While LOs have been introduced in relatively flexible 'process' forms, which can support reflection and communication around teaching practices, respondents describe pressures to develop more high-level, standardised and measureable 'product' LOs. Tensions between the forms seem likely to reduce the scope for LOs to support teaching and learning practices. [ABSTRACT FROM AUTHOR]

The production of valuable carbonyl compounds directly from alkenes via carbon–carbon double (C=C) bond cleavage is a highly important reaction. As a promising alternative to traditional metal-catalyzed thermal reaction conditions, photocatalysis offers an environmentally friendly and sustainable synthetic strategy. However, most photocatalysts used so far were homogeneous, molecular and transition metal-based catalytic systems. Here, we report a structural design strategy of conjugated microporous polymers (CMPs) as a class of metal-free, heterogeneous, stable and reusable photocatalysts for visible light-promoted C=C bond cleavage reaction. Via different electron donor and acceptor combinations in the CMP backbone structure, we systematically investigated the structural influence of the CMPs on their optical and electrochemical properties, thereby revealing the structure and performance relationship in the photocatalytic C=C bond cleavage reaction. As a result, the CMP with a specific electron donor–acceptor combination containing benzothiazole as a strong electron withdrawing unit and phenyl as a weak electron donating unit was the most efficient photocatalyst. The C=C bond in various alkenes, mostly styrene derivatives, could be successfully cleaved, forming aldehydes as a product with high conversion and moderate to high selectivity. The green aspect of the work is demonstrated by the utilization of visible-light, molecular oxygen as a cheap oxidant and water-based reaction medium. [ABSTRACT FROM AUTHOR]

Trajectories of stable linear systems with nonzero initial conditions are known to deviate considerably from the zero equilibrium point at finite time instances. In the paper we analyze transients in discrete-time linear systems and provide upper bounds on deviations (peaks) via use of linear matrix inequalities. An approach to peak-minimizing feedback design is also proposed. An analysis of peak effects for norms of powers of Schur stable matrices is presented and a robust version of the problem is considered. The theory is illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

A technique of multiobjective robust controller synthesis for airborne electro-optical device line-of-sight stabilization system is developed. The multiobjective synthesis of the robust control law for the stabilization system being considered is performed. [ABSTRACT FROM AUTHOR]

We formulate the control design problem for systems with structured uncertainty. The source of disturbances that affect both the input and the output of the system is represented by the same vector-valued signal. The method proposed for the solution of this problem is based on the concept of invariant ellipsoids. The efficiency of the approach is exemplified via application to a model of a fighter aircraft. [ABSTRACT FROM AUTHOR]

We consider discrete-time switched systems with switching of linear time-invariant right-hand parts. The notion of a connected discrete switched system is introduced. For systems with the connectedness property, we propose necessary and sufficient frequency-domain conditions for the existence of a common quadratic Lyapunov function that provides the stability for a system under arbitrary switching. The set of connected switched systems contains discrete control systems with several time-varying nonlinearities from the finite sectors, considered in the theory of absolute stability. We consider the case of switching between three linear subsystems in more details and give an illustrative example. [ABSTRACT FROM AUTHOR]

An algorithm was proposed to stabilize nonlinear systems with reduced level of impact of the measurement noise, parametric uncertainty, and external perturbation. Consideration was given to the noise of the measurements of dimensionality coinciding with that of the plant state vector. The parametric uncertainty and external perturbations can occur in any equation of the plant model. Conditions were obtained to calculate algorithm parameters in the form of solvability of the linear matrix inequality. Efficiency of the proposed scheme was illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

This paper presents the problem of robust finite-time H∞ control with transients for ocean surface vessels equipped with dynamic positioning (DP) system in presence of input delay. The main objective of this work is to design a finite-time H∞ state feedback controller, which ensures that all states of ship do not exceed a given threshold over a fixed time interval, with better robustness and transient performance subject to time-varying disturbance. Based on a novel augmented Lyapunov-Krasovskii-like function (LKLF) with triple integral terms and a method combining the Wirtinger inequality and reciprocally convex approach, a less conservative result is derived. In particular, an H∞ performance index with nonzero initial condition is introduced to attenuate the overconservatism caused by the assumption of zero initial condition and enhance the transient performance of ship subject to external disturbance. More precisely, the controller gain matrix for the DP system can be achieved by solving the linear matrix inequalities (LMIs), which can be easily facilitated by using some standard numerical packages. Finally, a numerical simulation for a ship is proposed to verify the effectiveness and less conservatism of the controller we designed. [ABSTRACT FROM AUTHOR]

The problem of synthesis of robust anisotropic suboptimal controllers is stated and solved for systems with uncertain parameters. This paper considers a general case of unstructured parametric linear-fractional uncertainty bounded in spectral norm. The initial synthesis problem for the uncertain system is embedded into the synthesis problem for some auxiliary system with certain parameters, augmented controlled output, and additional input. [ABSTRACT FROM AUTHOR]

Abstract: We report a general and novel semisynthetic strategy for the preparation of ubiquitinated protein‐activity‐based probes on the basis of sequential dehydroalanine formation on expressed proteins. We applied this approach to construct a physiologically and therapeutically relevant ubiquitinated α‐globin probe, which was used for the enrichment and proteomic identification of α‐globin‐modulating deubiquitinases. We found USP15 as a potential deubiquitinase for the modulation of α‐globin, an excess of which aggravates β‐thalassemia symptoms. This development opens new opportunities for activity‐based‐probe design to shed light on the important aspects underlying ubiquitination and deubiquitination in health and disease. [ABSTRACT FROM AUTHOR]

We propose methods to synthesize observers for the state and unknown input influences that ensure that estimation error is finite time bounded with respect to given sets of initial states and admissible trajectories or suppress initial deviations and uncertain bounded in L∞-norm external disturbances for time-varying continuous Lipschitz systems. Here gain coefficients of the observers depend on time and are determined based on numerical solutions of optimization problems with differential linear matrix inequalities or numerical solutions of the corresponding matrix comparison system. With the example of an electric drive system with elastic transmission of motion we show that their application for state estimation and unknown inputs for time-invariant systems proves to be more efficient (with respect to convergence time and accuracy of the resulting estimates) compared to observers with constant coefficients obtained based on numerical solutions of optimization problems with linear matrix inequalities. [ABSTRACT FROM AUTHOR]

Reforms and changing ideas about what higher education institutions are and should be have put pressure on academic identity. The present paper explores the way academics in Danish universities make sense of their changing circumstances, and how this affects their perceptions of their organization, their leaders and of themselves. The study highlights how the formal organizations' translations of external impulses and ideas constitute a more severe threat on the perceived identity of the academic staff than the impulses and ideas themselves. The findings indicate that with the tighter couplings of top-level management and the political system, the coupling and identification between academic staff and the formal organization may become weaker. Also, the behavioural responses perceived threats are studied, by examining the 'us'/'them' categorizations of the academics, providing a burgeoning conceptual framework for further studies into how academics change their actions as a result of reforms or organizational change. [ABSTRACT FROM AUTHOR]

We consider the stabilization problem for multiple-input switched linear systems operating under bounded coordinate disturbances and arbitrary switching signals. To solve this problem, we suggest an algorithm for the construction of a variable-structure controller based on methods of simultaneous stabilization theory. [ABSTRACT FROM AUTHOR]

Deubiquitinating enzymes (DUBs) catalyze the cleavage of ubiquitin from target proteins. Ubiquitin is post-translationally attached to proteins and serves as an important regulatory signal for key cellular processes. In this study, novel activity-based probes to study DUBs were synthesized that comprise a ubiquitin moiety and a novel disulfide warhead at the C-terminus. These reagents can bind DUBs covalently by forming a disulfide bridge between the active-site cysteine residue and the ubiquitin-based probe. As disulfide bridges can be broken by the addition of a reducing agent, these novel ubiquitin reagents can be used to capture and subsequently release catalytically active DUBs, whereas existing capturing agents bind irreversibly. These novel reagents allow for the study of these enzymes in their active state under various conditions. [ABSTRACT FROM AUTHOR]

A single crystal of a superconducting Ca(Pt As)(FePtAs) ( x = 0.01) was grown by the Bridgman method. The transition temperature was 32 K. The penetration field, H , was measured and the superconducting parameters, κ, λ, and ξ, were obtained from H . A fitting function was derived for the field dependence of the magnetization ( M− H curve) including the fishtail effect and the secondary peak using a statistical method. The temperature dependence of the upper critical field, H , was obtained from the fitting function and H (0) was estimated to be 134 T. In addition, the SDW transition in the normal state is reported. [ABSTRACT FROM AUTHOR]

We consider stabilization of bilinear control systems by means of linear output dynamical controllers. Using the linear matrix inequality technique, quadratic Lyapunov functions, and a special iterative method, we propose a regular approach to the construction of the stabilizability ellipsoid having the property that the trajectories of the system emanating from the points of this ellipsoid asymptotically tend to zero. The developed approach enables for an efficient construction of nonconvex inner approximations of domains of stabilizability of bilinear control systems. [ABSTRACT FROM AUTHOR]

We consider a novel multi-objective control problem where the criteria are generalized H -norms of transfer matrices of individual channels from the disturbance input to various objective outputs. We obtain necessary conditions for Pareto optimality. We show that synthesis of Pareto optimal controls can be done in terms of linear matrix inequalities based on optimizing Germeier's convolution, which also turns out to be the generalized H -norm of the closed-loop system with output composed of the objective outputs multiplied by scalars. As applications we consider multi-objective problems of vibration isolation and oscillation suppression with new types of criteria. [ABSTRACT FROM AUTHOR]

The selective oxidative cleavage of 1-octene to heptanal and heptanoic acid is reported. A range of model and silica-immobilized ruthenium(II) systems were evaluated. The MCM-41 and SBA-15 immobilized systems were found to show superior activity when compared to their homogeneous counterparts and were found to exert control over the selective formation of aldehydes or carboxylic acids. This could be achieved by varying the reaction times with very high yields being achieved at relatively short reaction times and low metal concentrations. The immobilized catalysts were characterized using nitrogen sorption, powder X-ray diffraction, transmission and scanning electron microscopies, solid-state NMR spectroscopy and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

We propose ways to synthesize state observers that ensure that the estimation error is bounded on a finite interval with respect to given sets of initial states and admissible trajectories and also simultaneous H -suppression at every time moment of initial deviations and uncertain deviations bounded in L -norm, external disturbances for non-autonomous continuous Lipschitz systems. Here the gain of the observers depend on the time and are defined based on a numerical solution of optimization problems with differential linear matrix inequalities or numerical solution of the corresponding matrix comparison system. With the example of a single-link manipulator we show that their application for the state estimating of autonomous systems proves to be more efficient (in terms of convergence time and accuracy of the resulting estimates) as compared to observers with constant coefficients obtained with numerical solutions of optimization problems with linear matrix inequalities. [ABSTRACT FROM AUTHOR]

We consider a multi-criteria problem of suppressing disturbances with linear feedback with respect to the state or output measured with noise. We assume that the system has N potentially possible inputs for disturbances from given classes, and the criteria are induced norms of operators generated by the system from the corresponding input to the common target output. We obtain necessary Pareto optimality conditions. We show that based on scalar optimization of the suppression level for the disturbances that act on all inputs we can synthesize Pareto suboptimal controllers whose relative losses compared to Pareto optimal controllers do not exceed 1 − $$\sqrt N /N$$ . Our results generalize to the case when disturbances from different classes may form coalitions. [ABSTRACT FROM AUTHOR]

We consider two-criteria control or filtering problems for linear systems, where one criterion is the level of suppression for Gaussian white noise with unknown covariance, and another is the level of suppression for a deterministic signal of bounded power. We define a new criterion, the level of suppression for stochastic and deterministic disturbances that act jointly in the general case on different inputs. This criterion is characterized in terms of solutions of Riccati equations or linear matrix inequalities. We establish that for the choice of optimal controller or filter with respect to this criterion relative losses with respect to each of the original criteria compared to Pareto optimal solutions do not exceed the value $$1 - {{\sqrt 2 } \mathord{\left/ {\vphantom {{\sqrt 2 } 2}} \right. \kern-\nulldelimiterspace} 2}$$ . We extend these results to dual control and filtering problems for systems with one input and two outputs, generalize them to the case of N criteria with loss estimate $$1 - {{\sqrt N } \mathord{\left/ {\vphantom {{\sqrt N } N}} \right. \kern-\nulldelimiterspace} N}$$ , and also apply them for systems with external and initial disturbances. We show a numerical example. [ABSTRACT FROM AUTHOR]