The Microwave Tokamak eXperiment at LLNL was designed to explore the physics of microwave interactions in plasmas using high power millimeter wave sources. We have used 140 GHz power from two sources, a gyrotron capab...
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The Microwave Tokamak eXperiment at LLNL was designed to explore the physics of microwave interactions in plasmas using high power millimeter wave sources. We have used 140 GHz power from two sources, a gyrotron capable of ∼ 1MW pulsed, 400 kW CW, and a free electron laser with 100-400 MW pulses of ∼ 10 ns for experiments, with results that we will describe here. Our interests center on non-linear absorption phenomena (FEL) and on heating, transport, and MHD control (FEL and gyrotron) in tokamak plasmas. In the first phase of the FEL experiments we were theoretically in the linear absorption regime, and our plasma transmission experiments gave results consistent with linear theory (with refraction included).
Both electrostatic and toner concentration (TC) electrophotographic process control systems can beconstructed with the proper use of bias current measurements of the development subsystem. A TC Idevelopability control...
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ISBN:
(纸本)0819403008
Both electrostatic and toner concentration (TC) electrophotographic process control systems can be
constructed with the proper use of bias current measurements of the development subsystem. A TC I
developability controller can be made by measuring the development bias current for each print or copy,
summing the measurements, subtracting offset currents and dispensing toner proportionally to this
developed charge measurement. If certain constraints are fulfilled, the system will operate at a constant
developed toner mass. Similarly, a photoconductor electrostatic measurement I control system can be made
by utilizing bias currents. This is accomplished by choosing a stable portion on the developed charge vs
development voltage relationship of the development subsystem. This setpoint is then used to measure
photoconductor test patch voltages by monitoring the bias current. In some cases this provides the same
function as an electrostatic voltmeter. These low cost techniques enable the practical process control
implementations in low and medium speed electrophotographic machines.
The analysis of some topological properties of the skeleton in the continuous plane leads us to propose a definition of the digital skeleton. The framework which is developed permits to define and to construct other r...
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ISBN:
(纸本)081940411X
The analysis of some topological properties of the skeleton in the continuous plane leads us to propose a definition of the digital skeleton. The framework which is developed permits to define and to construct other related remarkable subsets of sets or functions : minimal skeletons conditional bisectors perceptual graphs watershed lines.
In situ ellipsometry is of interest for monitoring and control of growing films. Its extreme sensitivityto thin layers also allows the measurement of the interface film frequently formed between a growing filmand the ...
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ISBN:
(纸本)0819403172
In situ ellipsometry is of interest for monitoring and control of growing films. Its extreme sensitivity
to thin layers also allows the measurement of the interface film frequently formed between a growing film
and the substrate. The installation and operation of an in situ system on two different vacuum coating
machines is described. The system records 'F and measurements every 5 seconds during film growth. We
present an algorithm for computing the thickness (d) and index (n'.ik) of a growing and an interface film on
a known substrate from five Y and measurements at different times during film growth. Numerical
solutions of the ellipsometer equations for d, n, and k performed using a 25 MHz 80386 microprocessor with
an 80387 math co-processor require about 30 minutes. Additional solutions beyond the first five data sets
require only two additional measurements. By taking data in repeated time intervals during the growth of
a film, we obtain a depth profile of its optical properties.
This paper presents an improved algorithm for motion compensated image coding. The algorithm can be appied to videophone or video-conferencing. Background detection is used to reduce the bit rate by eliminating the mo...
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ISBN:
(纸本)0819404101
This paper presents an improved algorithm for motion compensated image coding. The algorithm can be appied to videophone or video-conferencing. Background detection is used to reduce the bit rate by eliminating the motion information of the block. For a better estimation the object motion some of the blocks which include edge information are divided further into several subblocks according to the edge components. The algorithm shows the improvement of signal -to-noise ratio in the range of 1. 57-5. 57 dB compared to the other existing algorithms. The algorithm also shows the stable behavior for the abrupt movement as a result of the explicit usage of the edge information in the motion estimation.
Since 1988 oceanographic vehicles equipped with a variety of optical sensorshave been deployed successfully from ships-of-opportunity in the North Sea aspart of an environmental monitoring programme. The towed vehicle...
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ISBN:
(纸本)0819403164
Since 1988 oceanographic vehicles equipped with a variety of optical sensors
have been deployed successfully from ships-of-opportunity in the North Sea as
part of an environmental monitoring programme. The towed vehicles are deployed
and recovered by the ship's crew and the instrument packages are activated
automatically during the tow by electronic sea water switches. The vehicles
carry sensors for measuring chlorophyll fluorescence, turbidity, conductivity,
temperature, depth and upwelling and downwelling light in three wavebands; the
measurements are stored in a solid state logger. The filters used in the
irradiance sensors have wavelengths at 412, 450 and 550 nm with sensitivity at
0.1 pW cm2. The light measurements are used for the determination of the
diffuse attenuation coefficient and the reflectance of blue light (R4l2, R450)
and green light (R55O) and together with measurements of chlorophyll
fluorescence are being used for the development of an algorithm for estimation
of primary production in coastal waters and the open sea. Data are shown from a
number of fixed-depth and variable-depth vehicle deployments from selected
shipping routes in 1988/89, including a Copenhagen, Kattegat, Skagerrak, North
Sea, Harwich route. From March 1990 a nutrient sensor measuring combined
nitrite, nitrate in a continuous flow analyser will be carried by these towed
vehicles.
A fast algorithm has been developed for the reconstruction of an arbitrary permutation array from its two-dimensional aperiodic autoconelation function. The method is simple to apply. It is based on a backtracking sea...
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ISBN:
(纸本)081940408X
A fast algorithm has been developed for the reconstruction of an arbitrary permutation array from its two-dimensional
aperiodic autoconelation function. The method is simple to apply. It is based on a backtracking search of a difference triangle
associated with the permutation array. The issue of homometric arrays is also addressed. These are inequivalent arrays under
the group ofEuclidean motions which share the same autocorrelation function. It is shown that the developed algorithm determines
all homometric permutation arrays corresponding to a given autocorrelation function.
Optimization techniques are applied to the bispectrum. The Levenberg-Marquardt algorithm for nonlinear least squares is used to determine the parameters of binary stars. The conjugate gradient and conjugate direction ...
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ISBN:
(纸本)0819402818
Optimization techniques are applied to the bispectrum. The Levenberg-Marquardt algorithm for nonlinear least squares is used to determine the parameters of binary stars. The conjugate gradient and conjugate direction algorithms are used to estimate the full set of object phases and moduli. Simulated and observed data are utilized in each optimization.
In order to deliver the computational power required by real-time manipulation and display of multidimensional objects, we present a massively parallel octree architecture, based on a new Interconnection Network, the ...
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ISBN:
(纸本)0819402931
In order to deliver the computational power required by real-time manipulation and display of multidimensional objects, we present a massively parallel octree architecture, based on a new Interconnection Network, the Partitionable Spanning Multibus Hypercube (PSMH). Its goal is, to use one Processing Element per obel (object element), as opposed to one Processing Element per voxel (volume element). The underlying idea of the PSMH, is to take advantage of the data hierarchical ordering to reduce the computational cost. As a basic tool, we first derive a routing algorithm for the case of an object shift. Its running time is of order O(max(n3, m)), for an 8n PSMH, where m is the message length in bits. As we do not consider voxels but obels, we design a compaction algorithm, which meets the routing requirements. We get a compression ratio of O(2n). This is followed by a parallel neighbor finding technique, to account for the compaction in the routing operations.
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