AUTOMATIC CONTOURING USING BICUBIC FUNCTIONS

Geophysics ◽  
1972 ◽  
Vol 37 (4) ◽  
pp. 669-674 ◽  
Author(s):  
R. C. Hessing ◽  
Henry K. Lee ◽  
Alan Pierce ◽  
Eldon N. Powers
Keyword(s):  
Spatial Distribution ◽  
Cross Sections ◽  
Digital Computer ◽  
Smooth Surface ◽  
Contour Line ◽  
Contour Maps ◽  
Volume Calculations ◽  
Contour Lines ◽  
Data Points ◽  
Automatic Contouring

A method is described for using a digital computer to construct contour maps automatically. Contour lines produced by this method have correct relations to given discrete data points regardless of the spatial distribution of these points. The computer‐generated maps are comparable to those drawn manually. The region to be contoured is divided into quadrilaterals whose vertices include the data points. After supplying values at each of the remaining vertices by using a surface‐fitting technique, bicubic functions are constructed on each quadrilateral to form a smooth surface through the data points. Points on a contour line are obtained from these surfaces by solving the resulting cubic equations. The bicubic functions may be used for other calculations consistent with the contour maps, such as interpolation of equally spaced values, calculation of cross‐sections, and volume calculations.

Proposal of Contour Line Model for High-Speed End Milling Simulation

2020 ◽  
Vol 14 (1) ◽  
pp. 38-45 ◽  
Author(s):  
Isamu Nishida ◽  
◽  
Keiichi Shirase
Keyword(s):  
Cutting Force ◽  
Cross Sections ◽  
High Speed ◽  
End Milling ◽  
Cutting Edge ◽  
Contour Line ◽  
Memory Usage ◽  
Line Model ◽  
Milling Simulation ◽  
Contour Lines

A contour line model for end milling simulation, which realizes high-speed arithmetic processing by reducing memory usage, is proposed. In this model, a 3-dimensional shape can be expressed by superimposing the contour lines of the cross-sections obtained by dividing the workpiece along any axial direction. Therefore, the memory usage is reduced compared to a Z-map model or a voxel model as the interior information of the object can be eliminated. The contour line model can also be applied to complicated shapes having overhangs. Furthermore, cutting volume can be calculated from the interference area enclosed by two contour lines of the workpiece and the tool cross-sections. The workpiece shape can be changed by eliminating the interference area. In the contour line model, cutting force can also be predicted with an instantaneous rigid force model using the uncut chip thickness for each cutting edge from the positional relationship between the interference area and the cutting edge. To validate the proposed model, cutting experiments were conducted, which confirmed that the predicted machining shape had good agreement with the actual machined shape. Furthermore, it was confirmed that the cutting force can be predicted accurately.

Nẹw Analytic Volume Formulas and Automatic Checks for Earthworks

1978 ◽  
Vol 32 (2) ◽  
pp. 205-226
Author(s):  
A. Sanyaolu
Keyword(s):  
Cross Sections ◽  
Field Work ◽  
Contour Line ◽  
Computational Aspect ◽  
Traditional Methods ◽  
Volume Determination ◽  
Contour Lines ◽  
The Given ◽  
Simpson's Rule ◽  
Computational Processes

This paper on volume of earthworks eases (1) the computational aspect of volume determination from cross sections and from contours (the field aspect remains the same) and (2) both the field work and the computational processes in volume determination from spot heights. In the former case, the prismoidal correction and the mid-area assumption, or Simpson’s Rule, are eliminated, and the digressive process of interpolating a mid-contour line when the given number of contour lines is even is eliminated. In the latter case, formulas that eliminate the digressive process of gridding are provided. Another feature of this work is that the new formulas proposed have counterparts, which enables the speedy check of earthworks volume computations, a merit lacking in the traditional methods.

scholarly journals Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos

2019 ◽  
Author(s):  
Jörg Männer ◽  
Talat Mesud Yelbuz
Keyword(s):  
Spatial Distribution ◽  
Cross Sections ◽  
Embryonic Heart ◽  
Endocardial Cushions ◽  
Valveless Pumping ◽  
Matrix Layer ◽  
Heart Looping ◽  
Biological Aspects ◽  
Vertebrate Embryos ◽  
Heart Wall

The early embryonic heart is a multi-layered tube consisting of (1) an outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular matrix layer interposed between myocardium and endocardium, called “cardiac jelly” (CJ). During the past decades, research on CJ has mainly focused on its molecular and cell biological aspects. This review focuses on the morphological and biomechanical aspects of CJ. Special attention is given to (1) the spatial distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced heart looping stages, which leads to the formation of ventricular trabeculations and endocardial cushions. CJ acts as a hydraulic skeleton displaying striking structural and functional similarities with the mesoglea of jellyfish. CJ not only represents a filler substance, facilitating end-systolic occlusion of the embryonic heart lumen. Its elastic components antagonize the systolic deformations of the heart wall and thereby power the refilling phase of the ventricular tube. Non-uniform spatial distribution of CJ generates non-circular cross sections of the opened endocardial tube (initially elliptic, later deltoid), which seem to be advantageous for valveless pumping. Endocardial cushions arise from non-removed remnants of the original CJ.

scholarly journals Assessment of 2-D resistivity structures using 1-D inversion

Geophysics ◽  
1991 ◽  
Vol 56 (6) ◽  
pp. 874-883 ◽  
Author(s):  
L. P. Beard ◽  
F. D. Morgan
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Apparent Resistivity ◽  
Inversion Process ◽  
Square Prism ◽  
Contour Lines ◽  
The Cross ◽  
Schlumberger Array ◽  
Wenner Array

Schlumberger and Wenner array resistivity soundings over 2-D resistivity structures are interpreted using apparent resistivity pseudosections and cross‐sections constructed from 1-D inversions in order to determine the effectiveness of 1-D interpretations over such structures. Cross‐sections contoured from resistivities of inverted “layers” show distinct differences from the apparent resistivity pseudosections and may be used as interpretational aids. Contour lines in the cross‐sections locate the horizontal interfaces of the 2-D structures quite well. The vertically oriented segments of the cross‐section contours are relatively undistorted in the inversion process and are similar to the vertically oriented portions of contours in the apparent resistivity pseudosection. A simple, empirically determined formula is used to separate the sections into resistive and conductive zones and helps to define the geometry of the anomaly. In order to apply the formula, it is necessary to know whether the target is a relative conductor or a relative resistor. Except for the case of a square prism, the Schlumberger array appears to hold advantages over the Wenner in qualitatively assessing an anomaly. The primary drawback of the Wenner array is that its expanding potential electrodes create false anomalous zones and complicate interpretation. As might be expected, structures with long horizontal interfaces, i.e. those more nearly 1-D, yield the most accurate interpretations.

PROGRESS OF STUDIES, BASIN STUDY GROUP, BUREAU OF MINERAL RESOURCES

1970 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
K. G. Smith
Keyword(s):  
Cross Sections ◽  
Mineral Resources ◽  
Sedimentary Basins ◽  
Basic Data ◽  
Petroleum Exploration ◽  
Geological Survey ◽  
Study Group ◽  
Reservoir Properties ◽  
Thin Sections ◽  
Contour Maps

The Basins Study Group is part of the Subsurface Section of the Bureau's Petroleum Exploration Branch and was formed in 1962 to collect and review available basic data on the sedimentary basins of Australia and Papua-New Guinea. The Core and Cuttings Laboratory forms the second part of the Subsurface Section, and the Laboratory's technical staff contribute to basin reviews by carrying out analyses of various kinds, and assist in the collection of data principally by providing thin sections of various sedimentary formations.Recent activities of the Basins Study Group include a review of the Sydney Basin, and an increased effort to assemble basic data on all sedimentary basins, with particular emphasis on the Canning and Carnarvon Basins.The review of the Sydney Basin is nearing completion. It was undertaken with the co-operation of the Geological Survey of New South Wales and received generous support from petroleum exploration companies active in the Basin. The review included detailed petrological examination of twelve wells and selected outcrop samples. The results confirmed the previously-held opinions that the reservoir characteristics of Sydney Basin sediments are generally unfavourable. At present there are no indications of untested onshore areas where an improvement in reservoir properties may occur. The Bureau petrologists detected the rare mineral dawsonite in eight wells; the mineral occurred mostly in Permian sediments, both in marine and non-marine rocks, but it was recorded also from Triassic rocks in the Kurrajong Heights No. 1 well. The review of geophysical data from the Sydney Basin was concentrated mainly on seismic work. The magnetic tapes of three surveys were replayed and considerable improvement in records was effected. Record sections of all seismic surveys were reduced photographically to a horizontal scale of 1:50,000 and the reductions were spliced to provide easily-managed cross-sections. The geophysical review is nearing completion and structure contour maps and isochrons are in preparation.The collection of basic data is done for each sedimentary basin as it becomes available, but present emphasis is on assembling data from Western Australian basins: all seismic traverses in the onshore parts of the Canning and Carnarvon Basins have been plotted at 1:250,000 scale, and with the co-operation of the Geological Survey of Western Australia, bibliographies of the Canning, Carnarvon and Perth Basins have been compiled for issue as Open-file Records. Bibliographies of the Papuan and Ipswich-Clarence Basins have also been compiled.

scholarly journals Past and Present Practices of Topographic Base Map Database Update in Nepal

2020 ◽  
Vol 9 (6) ◽  
pp. 397 ◽  
Author(s):  
Nimisha Wagle ◽  
Tri Dev Acharya
Keyword(s):  
Land Use Planning ◽  
Data Quality Control ◽  
Vector Data ◽  
Contour Maps ◽  
Contour Lines ◽  
High Resolution Imagery ◽  
Field Data Collection ◽  
History Of ◽  
Quality Maps ◽  
Topographic Base

Topographic Base Maps (TBMs) are those maps that portray ground relief as the form of contour lines and show planimetric details. Various other maps like geomorphological maps, contour maps, and land use planning maps are derived from topographical maps. In this constantly changing world, the update of TBMs is indispensable. In Nepal, their update and maintenance are done by the Survey Department (SD) as a national mapping agency. This paper presents the history of topographical mapping and the reasons for the lack of updates. Currently, the SD is updating the TBM database using panchromatic and multispectral images from the Zi Yuan-3 (ZY-3) satellite with a resolution of 2.1 and 5.8 m, respectively. The updated methodology includes the orthorectification of images, the pansharpening of images, field data collection, digitization, change detection, and updating, the overlay of vector data and field verification, data quality control, and printing map production. A TBM in the Dang district of Nepal is presented as casework to show the changes in the area and issues faced during the update. Though the present digitizing procedure is time-consuming and labor-intensive, the use of high-resolution imagery has made mapping accurate and has produced high-quality maps. However, audit and automation can be introduced from the experiences of other countries for accurate and frequent updates of the TBM database in Nepal.

GEOPHYSICAL HISTORY OF PARENTIS OIL FIELD, FRANCE

Geophysics ◽  
1956 ◽  
Vol 21 (3) ◽  
pp. 815-827 ◽  
Author(s):  
Raoul Vajk ◽  
George Walton
Keyword(s):  
Cross Sections ◽  
Gravity Anomalies ◽  
Oil Field ◽  
Seismic Profiles ◽  
Contour Maps ◽  
History Of ◽  
Standard Oil Company ◽  
Aquitaine Basin ◽  
Surface Geology ◽  
Gravity Map

In 1951, the French Government granted an exclusive exploration permit to the Esso R.E.P. (a Standard Oil Company affiliate) over an area of 4,357,980 acres around Bordeaux in the northern part of the Aquitaine Basin, France. This area was investigated first by surface geology; then it was surveyed by the gravity meter. In checking the gravity anomalies by the reflection seismograph, a subsurface structure was found at Parentis in 1953, which was drilled in 1954, and was proved to be oil bearing. The Parentis oil field is the most important oil field, not only in France, but in all Europe outside the Iron Curtain. Gravity map, seismograph map, seismic profiles, telluric map and geological contour maps, and cross sections of the Parentis structure are presented.

Spatial Distribution of Carrier Concentration in 4H-SiС Crystal Grown by Solution Method

2016 ◽  
Vol 858 ◽  
pp. 57-60 ◽  
Author(s):  
Zhen Jiang Wang ◽  
Takahiko Kawaguchi ◽  
Kenta Murayama ◽  
Kenta Aoyagi ◽  
S. Harada ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Surface Morphology ◽  
Carrier Concentration ◽  
Smooth Surface ◽  
Doping Concentration ◽  
Solution Method ◽  
Peak Frequency ◽  
Longitudinal Optical ◽  
Longitudinal Optical Phonon ◽  
View Point

We investigated the spatial distribution of carrier concentration in n-type 4H-SiC grown by the solution method from the peak frequency of the longitudinal optical phonon-plasmon coupled (LOPC) mode of the Raman spectra on the surface. The carrier concentration at the position of the smooth terrace was higher than the carrier concentration at the position where the macrosteps were formed. This indicates the nitrogen incorporation efficiently occurs on the smooth surface where the density of macrosteps is relatively low. The different incorporation of nitrogen depending on the surface morphology can be understood from the view point of the adsorption time of impurity on the terrace. The present result implies that the uniform surface morphology is necessary to achieve uniform doping concentration in SiC crystal.

TORSION BALANCE STEP ANOMALIES IN NORTHERN TILLMAN COUNTY, OKLAHOMA

Geophysics ◽  
1945 ◽  
Vol 10 (4) ◽  
pp. 507-525
Author(s):  
K. Klaus
Keyword(s):  
Cross Sections ◽  
Torsion Balance ◽  
Second Derivative ◽  
Contour Maps ◽  
Probability Rating ◽  
Order Of Magnitude ◽  
Wichita Mountains ◽  
Gravity Map ◽  
High Degree ◽  
Quantitative Calculations

The results of a semi‐detailed areal torsion balance survey in Southwestern Oklahoma are shown by means of a gradient‐curvature map, a gravity map, two second derivative contour maps, and gravity and second derivative profiles. Detailed quantitative calculations were made of a number of geological cross sections, two of which are shown in Figs. 8 and 9. Fig. 9 represents the subsurface situation with the highest probability rating, since it combines a high degree of geological probability with the fact that it will reproduce the gravity and second derivative curves of Figs. 6 and 7 very closely. This interpretation embodies a fault with a throw of the order of magnitude of 10,000 feet. If this interpretation is substantially correct, it implies a thick sedimentary section in the down‐thrown block, which might be of great economic interest in prospecting for oil. A comparison of the gravity and second derivative data may be of interest to the geophysicist. The geologist may find the results of this survey interesting because of their possible bearing on the orogeny of the Wichita Mountains.

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