U.S. Contour Maps of Annual Energy Delivery by Flat Plate Collectors

1981 ◽  
Vol 103 (4) ◽  
pp. 360-361
Author(s):  
P. Major
Keyword(s):  
Flat Plate ◽  
Contour Maps ◽  
Energy Delivery

Economic Optimization of Stationary Nonevacuated CPC Solar Collectors

1987 ◽  
Vol 109 (1) ◽  
pp. 40-45 ◽  
Author(s):  
M. J. Carvalho ◽  
M. Collares-Pereira ◽  
J. M. Gordon
Keyword(s):  
Low Temperature ◽  
Flat Plate ◽  
Operating Temperature ◽  
Solar Collectors ◽  
Economic Optimization ◽  
Promising Alternative ◽  
Energy Delivery ◽  
Low Concentrations ◽  
East West ◽  
Concentration Ratios

Stationary, nonevacuated CPC solar collectors are a promising alternative to corresponding flat plate collectors in that they offer superior yearly energy delivery at comparable cost for low-temperature thermal applications. For realistic cost scenarios, we determine optimal concentrator configurations and concentration ratios, and calculate their sensitivity to variations in relative component costs, climate, orientation and collector operating temperature. For CPC’s that are to have the flexibility of either east-west or north-south orientation, optimized collectors are shown to have low concentrations of around 1.2, achieved by truncation from acceptance half angles of about 45 deg.

Nonimaging Solar Energy Concentrators (CPC’s) With Fully Illuminated Flat Receivers: A Viable Alternative to Flat-Plate Collectors

1986 ◽  
Vol 108 (3) ◽  
pp. 252-256 ◽  
Author(s):  
J. M. Gordon
Keyword(s):  
Solar Energy ◽  
Flat Plate ◽  
Closed Form ◽  
Ray Tracing ◽  
Production Costs ◽  
Viable Alternative ◽  
Solar Collectors ◽  
Low Concentration ◽  
Geometric Characteristics ◽  
Energy Delivery

Low-concentration, stationary, nonimaging concentrators (CPC’s) with flat receivers illuminated on both sides are considered as viable alternatives to flat-plate solar collectors. Closed-form, analytic formulae are derived for the geometric characteristics of two concentrator types of greatest interest (i.e., stationary collectors for year-round energy delivery), which enable calculations of collectible energy without computer ray-tracing stimulations. The relative merits of these concentrators in terms of energy collection and production costs are assessed with respect to each other as well as to flat-plate collectors.

Analysis of the 9th November 1990 flare

2000 ◽  
Vol 179 ◽  
pp. 229-232
Author(s):  
Anita Joshi ◽  
Wahab Uddin
Keyword(s):  
Image Processing ◽  
Two Dimensional ◽  
Temporal Behaviour ◽  
Contour Maps ◽  
Dimensional Measurements ◽  
Processing Software ◽  
Image Processing Software

AbstractIn this paper we present complete two-dimensional measurements of the observed brightness of the 9th November 1990Hαflare, using a PDS microdensitometer scanner and image processing software MIDAS. The resulting isophotal contour maps, were used to describe morphological-cum-temporal behaviour of the flare and also the kernels of the flare. Correlation of theHαflare with SXR and MW radiations were also studied.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Small Computer System for Micrograph Analysis

1981 ◽  
Vol 39 ◽  
pp. 270-271
Author(s):  
J. F. Hainfeld ◽  
J. S. Wall
Keyword(s):  
Large Range ◽  
Small Computer ◽  
Black And White ◽  
Contour Maps ◽  
Points Of Interest ◽  
Computer Aided Analysis ◽  
Specialized Hardware ◽  
Additional Memory ◽  
Selection Of ◽  
Publication Quality

Cost reduction and availability of specialized hardware for image processing have made it reasonable to purchase a stand-alone interactive work station for computer aided analysis of micrographs. Some features of such a system are: 1) Ease of selection of points of interest on the micrograph. A cursor can be quickly positioned and coordinates entered with a switch. 2) The image can be nondestructively zoomed to a higher magnification for closer examination and roaming (panning) can be done around the picture. 3) Contrast and brightness of the picture can be varied over a very large range by changing the display look-up tables. 4) Marking items of interest can be done by drawing circles, vectors or alphanumerics on an additional memory plane so that the picture data remains intact. 5) Color pictures can easily be produced. Since the human eye can detect many more colors than gray levels, often a color encoded micrograph reveals many features not readily apparent with a black and white display. Colors can be used to construct contour maps of objects of interest. 6) Publication quality prints can easily be produced by taking pictures with a standard camera of the T.V. monitor screen.

Two structural states of the Z-band in cardiac and skeletal muscle

1989 ◽  
Vol 47 ◽  
pp. 1022-1023
Author(s):  
J.P. Schroeter ◽  
M.A. Goldstein ◽  
J.P. Bretaudiere ◽  
L.H. Michael ◽  
R.L. Sass
Keyword(s):  
Skeletal Muscle ◽  
Cross Section ◽  
Real Space ◽  
Contractile State ◽  
Contour Maps ◽  
False Color ◽  
Grey Scale ◽  
Fourier Filtering ◽  
Cardiac Muscles ◽  
Enhancement Algorithm

We have recently established the existence of two structural states of the Z band lattice in cross section in cardiac as well as in skeletal muscle. The two structural states are related to the contractile state of the muscle. In skeletal muscle at rest, the Z band is in the small square (ss) lattice form, but tetanized muscle exhibits the basket weave (bw) form. In contrast, unstimu- lated cardiac muscle exhibits the bw form, but cardiac muscles exposed to EGTA show the ss form.We have used two-dimensional computer enhancement techniques on digitized electron micrographs to compare each lattice form as it appears in both cardiac and skeletal muscle. Both real space averaging and fourier filtering methods were used. Enhanced images were displayed as grey-scale projections, as contour maps, and in false color.There is only a slight difference between the lattices produced by the two different enhancement techniques. Thus the information presented in these images is not likely to be an artifact of the enhancement algorithm.

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