Inhibition of Herpes Simplex Virus Type 1 by Human Salivary Cystatin SN and its Proteinase Inhibitory Regions

Hiltke, Tara R.,Kennell, Alan F.,Bergey, Earl J.,Bobek, Libuse A. Korean Academy of Oral Biology and the UCLA Dental 2000 International Journal of Oral Biology Vol.25 No.1

Cystatins are a family cysteine proteinase inhibitors, many of which possess antiviral properties. Previous studies demonstrated that human cystatin C and salivary cystatin SN inhibit herpes simplex virus type 1〔HSV-1〕replication. The full-length cystatin C and SN do not function as serine proteinase inhibitors, but contain serine proteinase inhibitory regions. The goal of this study was to evaluate whether the inhibition of HSV-1 by cystatin SN occurs through its cysteine or serine proteinase inhibitory regions. using viral yield reduction assays, our results demonstrated that the N-truncated cystatin SN〔a deletion of one of the conserved cysteine proteinase inhibitory region〕was not able to effectively inhibit HSV-1〔20% versus 90% by the full-length cystatin SN〕. The results also showed that a circular peptide to the serine proteinase inhibitory region of cystatin SN inhibited HSV-1 by only 20%, while the linear peptide to the same region failed to inhibit HSV-1. Previous studies indicated that the inhibition of HSV-1 replicatin by cystatin SN occurred during the later stages of the viral infection. Thus, we have examined, by western blot analysis, the effect of cystatin SN on specific HSV-1 structural proteins 〔VP5, VP19, VP23, VP21/VP22a〕, as well as its effect on a non-structural DNA binding protein produced at an earlier stage in the viral life cycle〔ICP8〕. We report that cystatin SN reduced the production of total HSV-1 proteins, as well as all the individual proteins tested, while the circular peptide inhibited only two of the proteins tested, VP5 and VP19. In conclusion, the role of cystatin SN in HSV-1 inhibition appears to involve both ist cysteine and serine proteinase inhibitory regions.

Servo Drives State of the Art in Industrial Applications - A Survey

Kennel, R.,Kobs, G.,Weber, R. The Korean Institute of Power Electronics 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.1

Servo drives with microcomputer control provide the possibility of using modern and sophisticated control algorithms. As an additional feature it is possible to implement parallel and/or redundant software and hardware structures to realise safe motion or similar security functions. Unfortunately microcomputer control also has some impact on the behaviour of servo drives. Control algorithm, cycle time, sensors and interface have to be perfectly synchronised. Special control schemes are necessary on the line side (power supply) to meet the actual requirements concerning EMC. This contribution presents experiences and results obtained from a modern digital drive system pointing out the influences of low and high accuracy position sensors and the interdependencies mentioned above.

Predictive Control for Electrical Drives-A Survey

Ralph Kennel,Arne Linder 전력전자학회 2001 ICPE(ISPE)논문집 Vol.2001 No.10

During the last decades several proposals have been made in literature to use predictive control for inverter control - especially in electrical drives. These algorithms are completely different to the recursive but linear predictive algorithms known from information theory, where closed mathematical equations are used (e g Kalman-filters)<br/> Only few of the presented schemes have been realized in industrial applications so far After some further progress, however, the advan­tage of predictive algorithms might lead to an increased number of industrial implementations in the future.<br/> Besides the common basic idea - to use the well-known but strongly non-linear behaviour of inverters to precalculate the best switching times - there are many differences in the details of these proposals This contribution shows similarities and differences and attempts to design a "family tree" of predictive control algorithms This might grow to a first step to a theoretical approach to deal with predictive control schemes in a more generalised way.<br/>

Servo Drives State of the Art in Industrial Applications-A Survey

R.Kennel,G.Kobs,R.Weber 전력전자학회 2001 ICPE(ISPE)논문집 Vol.2001 No.10

Servo drives with microcomputer control provide the possibility of using modern and sophisticated control algorithms As an addi­tional feature it is possible to implement parallel and/or redundant software and hardware structures to realise safe motion or similar security functions<br/> Unfortunately microcomputer control also has some impact on the behaviour of servo drives. Control algorithm, cycle time, sensors and interface have to be perfectly synchronised Special control schemes are necessary on the line side (power supply) to meet the actual requirements concerning EMC.<br/> This contribution presents experiences and results obtained from a modern digital drive system pointing out the influences of low and high accuracy position sensors and the interdependences men­tioned above.

Servo Drives State of the Art in Industrial Applications-A Survey

R.Kennel,G.Kobs,R Weber 전력전자학회 2002 JOURNAL OF POWER ELECTRONICS Vol.2 No.1

Servo drives with microcomputer control provide the possibility of using modem and sophisticated control algorithms. As an additional feature it is possible to implement parallel and/or redundant software and hardware structures to realise safe motion or similar security functions Unfortunately microcomputer control also has some impact on the behaviour of servo drives. Control algorithm, cycle time, sensors and interface have to be perfectly synchronised. Special control schemes are necessary on the line side (power supply) to meet the actual requirements concerning EMC. This contribution presents experiences and results obtained from a modem digital drive system pointing out the influences of low and high accuracy position sensors and the interdependencies mentioned above.

Predictive Control for Power Converters and Drives: Concept, Applications, and Trends

Ralph M. Kennel,Jose Rodriguez,Zhenbin Zhang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Damage state evaluation of experimental and simulated bolted joints using chaotic ultrasonic waves

Fasel, T.R.,Kennel, M.B.,Todd, M.D.,Clayton, E.H.,Park, G. Techno-Press 2009 Smart Structures and Systems, An International Jou Vol.5 No.4

Ultrasonic chaotic excitations combined with sensor prediction algorithms have shown the ability to identify incipient damage (loss of preload) in a bolted joint. In this study we examine a physical experiment on a single-bolt aluminum lap joint as well as a three-dimensional physics-based simulation designed to model the behavior of guided ultrasonic waves through a similarly configured joint. A multiple bolt frame structure is also experimentally examined. In the physical experiment each signal is imparted to the structure through a macro-fiber composite (MFC) patch on one side of the lap joint and sensed using an equivalent MFC patch on the opposite side of the joint. The model applies the waveform via direct nodal displacement and 'senses' the resulting displacement using an average of the nodal strain over an area equivalent to the MFC patch. A novel statistical classification feature is developed from information theory concepts of cross-prediction and interdependence. This damage detection algorithm is used to evaluate multiple damage levels and locations.

Finite-Set Model Predictive Control of a Flying Capacitor Converter with Heuristic Voltage Vector Preselection

P. Stolze,P. Landsmann,R. Kennel,T. Mouton 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper presents a finite-set model predictive strategy for current control of a resistive-inductive-active load with a three-phase three-level flying capacitor converter. A heuristic method is used to reduce the calculation effort and to increase the prediction horizon. A disturbance observer determines the active part of the load. A hysteresis-based voltage balancing algorithm makes use of the redundancy of the 64 switching possibilities of the converter. The proposed method significantly reduces the calculation effort compared to classical finite-set model predictive control methods.

Robust Deadbeat Control for Synchronous Machines rejecting Noise and Uncertainties by Predictive Filtering

Jean-Francois Stumper,Sascha Kuehl,Ralph Kennel 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

A predictive current control scheme for permanentmagnet synchronous motors (PMSMs) with deadbeat performance is presented. Major problems of such control schemes are the delay of the discrete control system, machine parameter uncertainties and measurement noise. With conventional methods, the delay can be easily compensated, but the effects of uncertainties can only be handled when they are comparably slow. This paper presents a new filtering method that attenuates the negative effects of parameter uncertainties in fast transients. The predictive controller inputs are actual measurements averaged with previous current predictions. As a result, the stability range is extended, and the oscillations caused by parameter uncertainties are damped. Noise sensitivity is also reduced. The system response is not slowed down. The results are confirmed analytically and experimentally.

Decoupling of the Secondary Saliencies in Sensorless PMSM Drives using Repetitive Control in the Angle Domain

Chun Wu,Zhe Chen,Rong Qi,Ralph Kennel 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.4

To decouple the secondary saliencies in sensorless permanent magnet synchronous machine (PMSM) drives, a repetitive control (RC) in the angle domain is proposed. In this paper, the inductance model of a concentrated windings surface-mounted PMSM (cwSPMSM) with strong secondary saliencies is developed. Due to the secondary saliencies, the estimated position contains harmonic disturbances that are periodic relative to the angular position. Through a transformation from the time domain to the angle domain, these varying frequency disturbances can be treated as constant periodic disturbances. The proposed angle-domain RC is plugged into an existing phase-locked loop (PLL) and utilizes the error of the PLL to generate signals to suppress these periodic disturbances. A stability analysis and parameter design guidelines of the RC are addressed in detail. Finally, the proposed method is carried out on a cwSPMSM drive test-bench. The effectiveness and accuracy are verified by experimental results.