Search results for "Stability."
showing 10 items of 3015 documents
Biowaiver monograph for immediate-release solid oral dosage forms: acetylsalicylic acid.
2012
A biowaiver monograph for acetylsalicylic acid (ASA) is presented. Literature and experimental data indicate that ASA is a highly soluble and highly permeable drug, leading to assignment of this active pharmaceutical ingredient (API) to Class I of the Biopharmaceutics Classification System (BCS). Limited bioequivalence (BE) studies reported in the literature indicate that products that have been tested are bioequivalent. Most of the excipients used in products with a marketing authorization in Europe are not considered to have an impact on gastrointestinal motility or permeability. Furthermore, ASA has a wide therapeutic index. Thus, the risks to the patient that might occur if a nonbioequi…
Hexafluoro complex of rutherfordium in mixed HF/HNO3 solutions
2008
Formation of anionic fluoride-complexes of element 104, rutherfordium, produced in the 248 Cm( 18 O, 5n) 261 Rf reaction was studied by anion-exchange on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF 6 ] 2- , was formed in the studied fluoride ion concentrations of 0.0005-0.013 M. Formation of [RfF 6 ] 2- was significantly different from that of the homologues Zr and Hf, [ZrF 6 ] 2- and [HfF 6 ] 2- ; the evaluated formation constant of [RfF 6 ] 2- is at least one-order of magnitude smaller than those of [ZrF 6 ] 2- and [HfF 6 ] 2- .
Stabilization of a class of slowly switched positive linear systems: State-feedback control
2012
The main goal of this paper is to investigate the stabilization problem for a class of switched positive linear systems (SPLS) with average dwell time (ADT) switching in continuous-time context. State-feedback controllers and the corresponding switching law with ADT property are designed, which stabilize the closed-loop systems while keeping the states nonnegative. The proposed conditions, formulated as linear matrix inequalities, can be directly used for controller synthesis and switching designing. Finally, a numerical example is given to demonstrate the validity of the obtained results.
Robust H∞ reliable control for delta operator switched systems with time-varying delays under asynchronous switching
2014
The problem of robust H∞ reliable control for a class of delta operator switched systems with time-varying delays and actuator faults under asynchronous switching is considered in this paper. Asynchronous switching means that the switches between the candidate controllers and system modes are asynchronous. Based on the average dwell time approach and delta operator theory, a state feedback controller is designed such that the closed-loop system is exponentially stable with H∞ performance in the presence of actuator faults. The obtained results are formulated in the form of linear matrix inequalities (LMIs). Finally, a numerical example is provided to demonstrate explicitly the feasibility …
Stability and -Gain Control of Positive Switched Systems with Time-Varying Delays via Delta Operator Approach
2013
This paper investigates the problems of stability and -gain controller design for positive switched systems with time-varying delays via delta operator approach. The purpose is to design a switching signal and a state feedback controller such that the resulting closed-loop system is exponentially stable with -gain performance. Based on the average dwell time approach, a sufficient condition for the existence of an -gain controller for the considered system is established by constructing an appropriate copositive type Lyapunov-Krasovskii functional in delta domain. Moreover, the obtained conditions can unify some previously suggested relevant methods in the literature of both continuous- and…
Weight Adaptation Stability of Linear and Higher-Order Neural Units for Prediction Applications
2018
This paper is focused on weight adaptation stability analysis of static and dynamic neural units for prediction applications. The aim of this paper is to provide verifiable conditions in which the weight system is stable during sample-by-sample adaptation. The paper presents a novel approach toward stability of linear and higher-order neural units. A study of utilization of linear and higher-order neural units with the foundations on stability of the gradient descent algorithm for static and dynamic models is addressed.
A state-space approach to dynamic stability of fractional-order systems: The extended Routh-Hurwitz theorem
2017
This paper considers the case of Beck’s column, a linear elastic cantilever column subjected to a constant follower load at its free end. The column foundation is modeled as bed of hereditary elements that react with a vertical force distributed along the beam axis. The reacting supports are modeled with spring-pot element that is a two parameters mechanical elements (C; ) with an intermediate behavior between spring and dashpot. The constitutive equation of the spring-pot involves the so called fractional order derivatives and dynamic stability problem in presence of fractional-order operator must be faced for the Beck’s column. In this study , the authors generalize Routh-Hurwitz theorem …
Comparative Study of the Mechanical Unfolding Pathways of α- and β-Peptides
2015
Using molecular simulations, we analyze the unfolding pathways of various peptides. We compare the mechanical unfolding of a β-alanine's octamer (β-HAla8) and an α-alanine's decamer (α-Ala10). Using force-probe molecular-dynamics simulations, to induce unfolding, we show that the 3(14)-helix formed by β-HAla8 is mechanically more stable than the α-helix formed by α-Ala10, although both structures are stabilized by six hydrogen bonds. Additionally, computations of the potential of mean force validate this result and show that also the thermal stability of the 3(14)-helix is higher. It is demonstrated that β-HAla8 unfolds in a two-step fashion with a stable intermediate. This is contrasted wi…
Exploring the mass surface near the rare-earth abundance peak via precision mass measurements at JYFLTRAP
2019
The JYFLTRAP double Penning trap at the Ion Guide Isotope Separator On-Line (IGISOL) facility has been used to measure the atomic masses of 13 neutron-rich rare-earth isotopes. Eight of the nuclides, $^{161}$Pm, $^{163}$Sm, $^{164,165}$Eu, $^{167}$Gd, and $^{165,167,168}$Tb, were measured for the first time. The systematics of the mass surface has been studied via one- and two-neutron separation energies as well as neutron pairing-gap and shell-gap energies. The proton-neutron pairing strength has also been investigated. The impact of the new mass values on the astrophysical rapid neutron capture process has been studied. The calculated abundance distribution results in a better agreement w…
Parenting Styles, Prosocial, and Aggressive Behavior: The Role of Emotions in Offender and Non-offender Adolescents
2017
The aim is to analyse the parenting styles effects (acceptance, negative control and negligence) on prosociality and aggressive behavior in adolescents through the mediator variables empathy and emotional instability, and also, if this model fits to the same extent when we study adolescents institutionalized due to problems with the law and adolescents from the general population, and at the same time, if the values of the different analyzed variables are similar in both groups of adolescents. We carried out a cross-sectional study. 220 participants from schools in the metropolitan area of Valencia took part in the study. Also, 220 young offenders took part recruited from four Youth Detenti…