1,254 research outputs found
Low emittance lattice for the storage ring of Turkish Light Source Facility TURKAY
Turkish Accelerator Center) project is aimed to build an accelerator center
in Turkey. The first step of the project is to construct IR-FEL facility. The
second stage is to build a synchrotron radiation facility named TURKAY, which
is the third generation synchrotron radiation light source that aimed to
achieve high brilliance photon beam from low emittance electron beam at 3 GeV.
The electron beam parameters highly depend on the magnetic lattice of the
storage ring. In this paper a low emittance storage ring for TURKAY is proposed
and beam dynamic properties of the magnetic lattice are investigated.Comment: 5 pages, 5 figure
Scaled bilateral teleoperation using discrete-time sliding mode controller
In this paper, the design of a discrete-time slidingmode
controller based on Lyapunov theory is presented along
with a robust disturbance observer and is applied to a piezostage
for high-precision motion. A linear model of a piezostage was
used with nominal parameters to compensate the disturbance
acting on the system in order to achieve nanometer accuracy. The
effectiveness of the controller and disturbance observer is validated
in terms of closed-loop position performance for nanometer
references. The control structure has been applied to a scaled
bilateral structure for the custom-built telemicromanipulation
setup. A piezoresistive atomic force microscope cantilever with a
built-in Wheatstone bridge is utilized to achieve the nanonewtonlevel
interaction forces between the piezoresistive probe tip and
the environment. Experimental results are provided for the
nanonewton-range force sensing, and good agreement between
the experimental data and the theoretical estimates has been
demonstrated. Force/position tracking and transparency between
the master and the slave has been clearly demonstrated after
necessary scalin
Measuring the Quality of Bank Regulation and Supervision, with an Application to Transition Economies
This study develops a method to evaluate the quality of a legal framework for bank regulation and supervision (RS) by developing an extensive set of criteria and a coding system. Using this method, we generate an original set of measurements for RS by evaluating the letter of banking laws of 23 transition economies. In doing so, we also utilize the Basle guidelines on banking supervision and the related literature. The indices of RS indicate that legal banking reforms in Poland, Hungary and Estonia have been more ambitious than the rest of the countries in transition. In general, however, banking laws in transition economies indicate a lower regulatory and supervisory quality than indicated by the German banking law, if one is willing to choose the latter as a benchmark. This data set permits an empirical analysis of the relationship between legal RS and macroeconomic performance. The empirical evidence in the paper shows a significant positive relationship between RS and real GDP growth in transition economies.Bank regulation and supervision, growth, transition economies
Function based control for bilateral systems in tele-micromanipulation
Design of a motion control system should take into
account (a) unconstrained motion performed without interaction
with environment or any other system, and (b) constrained
motion with system in contact with environment or other systems.
Control in both cases can be formulated in terms of maintaining
desired system configuration what makes essentially the same
structure for common tasks: trajectory tracking, interaction force
control, compliance control etc. The same design approach can be
used to formulate control in bilateral systems aimed to maintain
desired functional relations between human and environment
through master and slave motion systems. Implementation of
the methodology is currently being pursued with a custom built
Tele-micromanipulation setup and preliminary results concerning
force/position tracking and transparency between master and
slave are clearly demonstrated
Development of a micromanipulation system with force sensing
This article provides in-depth knowledge about our undergoing effort to develop an open architecture micromanipulation system with force sensing capabilities. The major requirement to perform any micromanipulation task effectively is to ensure the controlled motion of actuators within nanometer accuracy with low overshoot even under the influence of disturbances. Moreover, to achieve high dexterity in manipulation, control of the interaction forces is required. In micromanipulation, control of interaction forces necessitates force sensing in milli-Newton range with nano-Newton resolution. In this paper, we present a position controller based on a discrete time sliding mode control architecture along with a disturbance observer. Experimental verifications for this controller are demonstrated for 100, 50 and 10 nanometer step inputs applied to PZT stages. Our results indicate that position tracking accuracies up to 10 nanometers, without any overshoot and low steady state error are achievable. Furthermore, the paper includes experimental verification of force sensing within nano-Newton resolution using a piezoresistive cantilever endeffector. Experimental results are compared to the theoretical estimates of the change in attractive forces as a function of decreasing distance and of the pull off force between a silicon tip and a glass surface, respectively. Good agreement among the experimental data and the theoretical estimates has been demonstrated
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