Aid In Interpretation Research Articles

Electrocardiogram computer analysis. Practical value of the IBM Bonner-2 (V2 MO) program

One thousand ECGs were selected from those taken from an adult population and analyzed by three cardiologists to assess the performance of the IBM Bonner-2 (V2 MO) program. The sample included 200 ECGs with 248 myocardial infarctions, 200 with conduction abnormalities, 100 with ventricular hypertrophy, 300 normals and 200 with electronic pacemakers. In the MI group, there was a total sensitivity of the program with respect to the readers of 88% (218/248) with 19 (8%) program errors and 90% (248/275) specificity. In 53 ECGs with two MI statements, the sensitivity was 89% (47/53). The sensitivity in conduction abnormalities was 93.4% (183/196) with 98.7% specificity (800/810). The sensitivity in LVH was 90% (74/81) and in RVH 83% (5/6). Among the normals, the specificity was 98.6% (289/293). The sensitivity to PVCs was 84% (56/67), to atrial fibrillation 87% (48/55), to SVCs 58.6% (17/29) and to electronic pacemakers 65% (127/196). Recognizing the limitations of this type of analysis, this study indicates that the V2 MO version compares favorably with the earlier versions of the same program and is a valuable aid in ECG interpretation with rapid acceptance by physicians.

Permian Marine Sand Wave Complex in Central Arizona: ABSTRACT

The Lower Permian Rancho Rojo Member of the Schnebly Hill Formation exhibits unusual large-scale compound or intraset cross-stratification near Sedona, Arizona. The very fine-grained, moderately sorted subfeldspathic to quartzarenite, is divided into four facies. The lowermost tabular-planar foreset facies comprises giant foresets that dip westward at 13-19°, with foreset bundles of planar, wavy, and minor intraset cross-strata separated by surfaces of erosion. The intraset cross-stratified facies consists of giant foresets arranged in bundles that contain compound cross-stratification including tabular-planar herringbone pattern and complex trough sets separated by planar and trough erosion surfaces. The westerly dipping master sets have superimposed intrasets that display widely varying current vectors. Both facies were deposited in a marine sand wave complex following rapid transgression across underlying fluvial-estuary deposits. The erosion surfaces that bound the master sets were likely formed during storms. The intraset planar and trough sets were formed by migrating tidally driven megaripples on the westerly dipping surfaces of the sand wave. Documentation is provided by close similarities with other reported ancient sand waves and the newly proposed Allen sand wave model. These two facies are overlain by the ripple-laminated and homogeneous sand facies that developed during the waning stages of sand wave deposition. The former was probably produced by shoaling waves and the latter by bioturbation. The well-exposed Rancho Rojo will help advance the study of these controversial sand bodies and aid in the paleogeographical interpretation of the Permian in central Arizona. End_of_Article - Last_Page 903------------

Results of experimental and test TEM surveys, Elura deposit, Cobar, NSW

The Bureau of Mineral Resources (BMR) has carried out a series of TEM test surveys at Elura to investigate the advantages of various loop sizes and configurations, and to assess the application of recent developments in quantitative methods of interpretation. The use of multi-component and in-loop systems can be useful in extracting extra spatial information on anomaly sources, but care must be taken with interpretation. Model studies offer a valuable aid in interpretation. The design of multi-turn TEM receiving coils should ensure that the coil does not distort the shape of the transient decay curve. In assessing methods of interpretation it was found that SIROTEM data could not be used quantitatively in the coincident loop mode for signal levels below 10 mV/A There is a need for accurate calibration facilities for low signal levels, as parameters such as loop size and inductance are varied. This calibration is also necessary for systems such as the Crone PEM if they are to be used quantitatively. It is possible that a separated-loop configuration (e.g. the in-loop geometry) will have to be employed to reduce effects such as self-inductance, to allow accurate recording at low signal levels.

Evolution of the first generation folds in a marble unit (Damara Orogenic Belt, Nambia)

An exhaustive field study of complex minor fold structures has been directed at a better understanding of the individual fold-like features of a complex structure, to gain insight into their development and into the evolution of the major folds. It has been found conceivable and in practice, enlightening to explain complexity by the retention of geometrical features from an earlier stage of deformation within the same folding phase. Irregularities in fold and layer geometry were, whenever possible, interpreted as intact or modified relicts from such an earlier stage. Results of experimental work on fold development have been used as an aid in interpretation.

Cooperative and Noncooperative Behavior in Animals

Put in one sentence, the central message of this article is: There are theoretical reasons and empirical evidence to suggest that the performance of cooperative and noncooperative behavior by animals in many situations is best explained by considering both fitness benefits and the contributions of other group members to cooperative behavior. The formal model presented here indicates one way in which fitness benefits and the actions of other group members can be combined to yield predictions about the performance of cooperative and noncooperative behavior. This model is contrasted with the population genetics models applying to cooperative and noncooperative behavior. These latter models predict only the presence or absence of cooperative and noncooperative behavior from fitness considerations; they do not predict the actual, quantifiable amount of each kind of behavior, and they do not recognize the possibility that the amount of a behavior may be adjusted in a manner contingent upon the behavior of other animals in a group. It is suggested that the model presented here be used as a heuristic device to stimulate and guide detailed, quantitative studies of the dynamics of cooperative and noncooperative behavior in animal groups. Three general hypotheses that are generated by the model and that can be used to guide research and aid in interpretation are discussed. The three hypotheses concern how investment in cooperative and noncooperative behavior changes with group size, the presence of equilibrium patterns in certain situations involving cooperative behavior, and the adjustment to changes in the unit costs of cooperative and noncooperative behavior. Several studies by which the hypotheses might be tested are briefly outlined, and finally two simplifying assumptions made in the construction of the model are discussed.

A Study of Oceanic Boundary-Layer Characteristics Including Inertial Oscillation at Three Drifting Stations In the Arctic Ocean

Abstract Measurements of surface drift and near-surface currents taken during August 1975, at drifting ice stations of the AIDJEX experiment in the central Arctic, are used to infer the response of the upper ocean to the passage of two frontlike wind events. As an aid in interpretation, a multilevel, time-dependent, dynamical boundary-layer model commensurate with earlier investigations of PBL turbulence and ice drift versus surface wind statistics is developed and shown to reproduce the main features observed, including energetic inertial oscillation of the ice cover and mixed layer, relatively small currents at 30 m (∼5 m into the pycnocline), and little inertial-period shear between the ice and currents measured at 2 m. The model employs an eddy viscosity dependent on the surface friction velocity (u*) and the nondimensional depth (fz/u*) in the well-mixed layer, and on the product of the local stress and the local Obukhov length in the upper pycnocline. When the dominant horizontal length scale (relat...

A description of nucleation of folds and boudins in terms of vorticity

Abstract For slow plane flow of an incompressible viscous fluid, vorticity is a potentially valuable interpretational aid, being simply related both to velocity (via the Biot-Savart Law) and to pressure (via the equations of motion). Using semi-qualitative arguments based on the equations of motion, the continuity conditions for velocity and traction, and an assumption compatible with the small-amplitude formulation, it is possible to determine the essential characteristics of the vorticity generated near a small deflection on an otherwise flat interface of a viscous layer subjected to compression or extension. By application of the Biot-Savart Law, this vorticity distribution is seen to correspond to a perturbing velocity field which is responsible for initiation of new deflections on both interfaces. These secondary deflections give rise, in turn, to additional vorticity. For compression of a layer which is more viscous than its surroundings, there is mutual enhancement between vorticity and deflection geometry, resulting in a “runaway” nucleation (and amplification) of folds at everincreasing distances from the original deflection. The response of a more-viscous layer under extension is more restrained, owing to a degree of destructive interference between the vorticity generated at the upper and lower interfaces; the mechanism for nucleation is essentially the same as for folding, but the resulting pinch-and-swell structure is always small in amplitude.

Crack-detectives foil aircraft failure: Detecting flaws in aircraft is based on nondestructive testing with new interpretive aids on the way

Considers the art of detecting and controlling structural flaws in aircraft caused by accidental damage, poor design or normal deterioration. This entails nondestructive evaluation methods (NDE) which apart from visual examination of the aircraft also uses techniques using ultrasonics, eddy currents, radiography, dye penetrants, and magnetic particles.

Application of Regional Geochemical Data to Uranium Exploration: ABSTRACT

Hydrogeochemical and stream-sediment reconnaissance data generated by the U.S. Department of Energy's National Uranium Resource Evaluation program can be used to identify geologic environments favorable for uranium or base metal deposits. Open-filed analytical data for 1 × 2° NTMS quadrangles are obtained on magnetic tape from Oak Ridge National Laboratory and transferred to disk for interactive computer use. Data may then be organized into subsets according to sample type, geologic, or physiographic units; smoothed using block or nearest-neighbor averaging techniques; and power transformed to normalize frequency distributions. Multivariate statistical techniques, including principal component, discriminant, and multiple regression analyses, aid in interpretation. A contrast filter may be used to identify areas that are significantly different from their local background. Machine-generated color or black and white maps are produced from raw elemental analyses, elemental ratios, and statistical parameters such as factor scores and multiple regression residuals. The data may be represented at any scale, using a variety of symbol or color schemes designed to cartographically enhance the appearance of anomalous areas. Results of the geochemical interpretation are used to select target areas several tens of square kilometers in size. Examples from the Colorado Plateau and other areas illustrate how the interpretive techniques are used. Both the data and data analysis techniques have wide application in mineral exploration. Because of the extensive suite of elements represented, the data can be End_Page 695------------------------------ beneficial to any organization involved in frontier exploration for uranium or base metals. End_of_Article - Last_Page 696------------

Evolution and Stress History of Low-Permeability Upper Cretaceous Gas Reservoirs, Rocky Mountains: ABSTRACT

The physical properties of the Mesaverde gas reservoirs in Wyoming, Utah, Colorado, and New Mexico are the result of stress-induced changes that modified the sediment's original properties. Consideration of the stress history aids in interpretation of well log data and in understanding the reservoir performance that is controlled by natural or artificial fractures. The poorly sorted and discontinuous reservoir sands were formed in a shifting nearshore environment in a region of nascent tectonic compression. Rapid sedimentation induced compaction and diagenesis, and later Tertiary burial continued compression and promoted some thermal stress. Laramide wrench-faulting could cause early shear fractures; a later uplift-reburial-uplift sequence, together with episodes of extensional tectonics, could promote tensional fracturing and a re-orientation of fractures and other structures in the well-indurated sediments. Reservoir style is a result of several aspects of basin history, e.g., the depth of Tertiary burial in the Green River versus the San Juan basin. The regions considered are now generally inactive seismically, and there has been very little igenous activity since Cretaceous time, as contrasted to most nearby areas in the Rocky Mountains. End_of_Article - Last_Page 794------------

Trace Fossils From Proterozoic Sediments of Godavari Valley, South India: ABSTRACT

Reports of Precambrian trace fossils are rare and generally doubtful. Unequivocal evidence of biogenic structures has been recorded for the first time from layers in shallow-water sedimentary rocks of a Proterozoic sequence (= 1,300 m.y. ago) in the Godavari Valley of south India. Five different suites of structures have been noted. Each of these suites is closely related to a particular lithofacies with a well-defined position in the stratigraphic sequence. Vertical burrows and spreiten distributed in delicate sheets are confined to limestone facies. Inclined burrows making interconnected networks are profuse in a shale sequence, locally with low rank metamorphism. Surface trail marks and horizontal to nearly horizontal burrows, exposed on the bedding planes, are confined to the shallow, sub-tidal sandy facies. Vertical boring structures have been recorded from a thick limestone of possible lagoonal origin. Close relation of sedimentary lithofacies and morphotypes of the biogenic structures and their stratigraphic zonation is clearly demonstrated in Ramgundam (79°26^primeE, 18°45^primeN) and Somanpalli (80°15^primeE, 18°46^primeN). Observations in other parts of the valley reveal that these trace fossil suites may be used as an excellent aid in paleofacies interpretation and in stratigraphic correlation of the nonfossiliferous, deformed sequence. Preferred en echelon orientation of the features of positive relief at high angle to ripple crests; highly sinuous, lobated, and irregular pattern on bedding planes; linear grooves with parallel ridges on either side; intersection of sinuous relief features or grooves; and gentle U-shapes of the contacts of the features with bedding surfaces all point to biogenic origins for these structures. End_of_Article - Last_Page 691------------

Electrocardiographic mapping after exercise for evaluation of coronary bypass graft surgery

Electrocardiographic mapping after exercise adds an extra dimension to the routine exercise test because a measure can be made of the area and severity of electrocardiographic changes that occur after exercise. The value of this technique in assessing coronary bypass graft surgery was investigated in 50 patients who had postoperative coronary angiography after undergoing such surgery. The patients were classified into three groups: The 35 patients in Group 1 were free of pain at follow-up and had no new precordial Q waves. Among these, 24 patients had patent grafts and no precordial area of S-T segment change after exercise. The remaining 11 patients had areas of exercise-induced S-T segment change postoperatively; 10 of the 11 had at least one blocked graft and 1 had a patent although poorly functioning graft. The 10 patients in Group 2 continued to have chest pain after operation. Eight of the 10 had an area of S-T segment change that persisted after exercise and at least one blocked graft; the 2 patients without precordial S-T segment changes after exercise had patent grafts. The five patients in Group 3 were in poorer condition after operation; three had greater areas of S-T segment change after exercise, and the remaining two had new areas of Q waves. All patients had at least one occluded graft. In 8 (16 percent) of the 50 patients studied before operation precordial areas of S-T segment change after exercise that were identified with electrocardiographic mapping were not identified using a modified 12 lead system. After operation, mapping revealed precordial areas of ischemia in 24 patients; In 4 (17 percent). These areas were not detected with the modified 12 lead electrocardiogram. Electrocardiographic mapping after exercise is a simple noninvasive test that objectively describes the effects of coronary bypass surgery on myocardial ischemia and aids in interpretation of a patient's report of a change in the frequency of angina. Because it provides more information than a modified 12 lead system it may reduce the need for postoperative angiocardiography.

Distance relationships in theoretical models of carcinogenesis.

Abstract A number of quantitative models of environmental and genetic carcinogenesis have been proposed. It may be possible to ameliorate difficult problems of empirical verification by deriving the distance relationships inferred by a particular model of carcinogenesis. In addition, theoretical statements of the cancer-inducing process may inform empirical studies of the spatial variation in cancer occurrence and aid in model selection and interpretation. This paper introduces carcinogenetic theory and provides examples of the geographical application of theoretical models of carcinogenesis.

GEOMORPHOLOGICAL DEVELOPMENTS AND CLASSIFICATION OF THE QUATERNARY VOLCANOES IN JAPAN

The evolutions of 140 Quaternary volcanoes in Japan have been studied mainly with the aid of air-photo interpretation. The study has revealed that these volcanoes have been evolved along three definite courses. On the basis of the result, the Quaternary volcanoes in Japan are classified into three types: A-, B and C-type volcanoes. A-type volcanoes generally take an evolutional course as follows : The 1 st stage : A gently sloping large cone with simple structure is constructed. The cone is composed of mafic thin lava flows and scoria falls (olivine-pyroxene basalt-andesite, SiO2 56% in average). The 2nd stage: Thick lava flows are added on the upper slope of the large cone. Therefore, the surfaces of the cone show stepped slopes. In some volcanoes, the cone iss greatly destructed by the Bandaian eruption just after the maximum growth of it, forming a horseshoe-shaped caldera on the summit. The 3rd stage: Explosive eruptions eruptions of pyroclastic flows and falls (pumiceous, hornblende-pyroxene andesite-dacite, SiO2 62%) are repeated, causing destruction of the older cone and construction of pyroclastic cones and pyroclastic flow surfaces. The 4th stage: A small caldera is formed on the summit of the cone, constructing lava domes within it. Typical cone volcanoes with simple structure, such as Fuji and Yotei Volcanoes, have developed only to the 1st stage. The volcanoes with horsehoe-shaped calderas, such as Chokai and Bandai Volcanoes, have evolved to the 2nd stage. Oshima-Komagatake and Asama Volcanoes frequently erupting pumice flows and falls, have developed to the 3rd stage. Truncated volcanoes with small calderas on the summits such as Akagi and Haruna Volcanoes, have evolved to the 4th stage. Small Krakatoan caldera volcanoes, such as Nigorigawa and Hijiori Volcanoes would be considered as A-type volcanoes which have developed to the 3rd or 4th stage without passing through the 1st and 2nd stages, because the properties and volumes of the eruptive materials are similar to those of typical A-type volcanoes. A-type volcanoes are subdivided into three-Al, A2, A3 type volcanoes-according to the difference of the developmental stage of each volcano. A1-type volcanoes are typical, large cone volcanoes with simple structure, having developed to the earlier stage (the 1st and/or 2nd stage). A2-type volcanoes are dissected or truncated composite volcanoes, having developed to the later stage (the 3rd and/or 4th stage). A3-type volcanoes are small Krakatoan caldera volcanoes, having developed to the later stage without passing through the earlier stage. B-type volcanoes are large Krakatoan caldera volcanoes which are characterised by voluminous pumice eruptions, resulting in the formations of large calderas, such as Aso, Ata, Towada and so forth. Their evolutions may be simplified as follows: Caldera stage Voluminous acidic pumice flows (ash flows) and falls violently issue out, resulting in formation of a large caldera and extensive pyroclastic flow surfaces. Post caldera stage Within and around the large caldera a-type volcanoes (small stratovolcanoes), histories and landforms of which are similar to those of A-type volcanoes, are constructed. They aree also subdivided into three-a1, a2 and a3 type volcanoes. Classification and definition of a1, a2 and a3-type volcanoes are same to those of A1, A2 and A3 type volcanoes. Sakurajima Volcano standing at the rim of Aira Caldera Volcano is regarded as a1-type volcano. Examples of a2-type volcanoes are Mashu Volcano rising at the eastern rim of Kutcharo Caldera Volcano, and Usu Volcano formed at the southern rim of Toya Caldera Volcano. Tarumai Volcano built up at the southern rim of Shikotsu Caldera Vocano is a3-type volcano.

SPHERICAL HARMONIC DEFORMATION

A radically new method of structural analysis is proposed which relates the deformation of all rocks to a three‐dimensional model of close‐packed spheres and deformation ellipsoids. All rocks exist under variable stress conditions and are deformed, but the principles of three‐dimensional deformation are poorly understood by many geologists and geophysicists. An understanding of rock deformation in three dimensions is a very valuable aid in geological interpretation and in the search for hydrocarbons. The method proposed provides the geologist, geophysicist and associated scientific disciplines with a means of understanding complex, three‐dimensional deformation and attempts to explain all deformational phenomena from mud cracks to plate tectonics. Deformation is a spherical harmonic waveform which, although complex in detail, is intrinsically no more mathematically complicated than the reciprocal of the square root of three. The analysis is illustrated by examples of “compressive” deformation from the Tertiary fold belt of Spitsbergen and the “tensional” or “gravitational” deformation in the Viking Graben of the Northern North Sea.

The Future of Reference and Information Service in the Public Library

Previous articleNext article No AccessThe Future of Reference and Information Service in the Public LibraryThomas ChildersThomas Childers Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Library Quarterly Volume 48, Number 4Oct., 1978Proceedings of the Thirty-Ninth Annual Conference of the Graduate Library School, April 10-11, 1978. The Public Library: Circumstance and Prospects Article DOIhttps://doi.org/10.1086/600836 Views: 6Total views on this site Copyright 1978 The University of ChicagoPDF download Crossref reports no articles citing this article.

INTERPRETATION OF BURIED ELECTRODE RESISTIVITY DATA USING A LAYERED EARTH MODEL

The layered earth model is a fundamental interpretation aid for direct current resistivity data. This paper presents a solution for the layered earth problem for a buried current source and a buried receiver. The model is developed for source and receiver electrodes buried anywhere within a horizontally stratified layered earth containing an arbitrary number of resistivity layers. Model results for the normal well‐logging array indicate that large departures between true and apparent resistivity can be caused by thin beds or highly resistant layers. A true resistivity distribution from well logs can be established by modeling when the effects from borehole rugosity and fluid resistivity are negligible. The equations derived for resistivity well logs can be used to interpret hole‐to‐hole, hole‐to‐surface, and conventional surface array data. A field example demonstrates that deviations between hole‐to‐hole field data and model results, based on well logs in the receiver hole, can be accounted for by combining the resistivity logging models in the receiver holes with information from geologic logs. Differences between the field data and the layered‐model results are attributed to lateral changes between or near the source and receiver holes.

Convergent and Discriminant Validity in Item Analysis

Described is an alternative algorithm for item analysis in which item discrimination indices have been defined for item distractors in addition to their traditional definition for the scored alternative. Also, the Campbell and Fiske concept of convergent and discriminant validity was reconceptualized from the test to the item level and proposed as an aid in interpretation of results of item analysis.

Transfer functions for the seismic research observatory seismograph system

Abstract Transfer functions are given for all basic elements of the Seismic Research Observatory (SRO) seismograph system. These include the seismometer, response shaping filters, and anti-alias filters. With these transfer functions the amplitude and phase responses can be calculated at any frequency by the evaluation of a ratio of polynomials in s = iω. Amplitude and phase response plots and impulse responses are given for the most important overall transfer functions. In addition, long- and short-period group delays have been calculated by numerical differentation of phase responses. In the long-period case a simple polynomial approximation to the group delay is given as an aid in interpretation of data. The transfer functions are exact and follow from the integral design of the system.

Construct validity of four basic Vocational Interest factors

To find evidence of the generalizability of four interest factors established for tests within the Roe-Holland framework, factor scores derived from a Vocational Interest Inventory grounded in Roe's system were correlated with the empirically based Strong-Campbell Occupational scale scores. For this sample of 300 counseling clients, a majority of the hypothesized relations were found, and arranging the occupations along these bipolar dimensions both sharpened the definitions of the factors and provided an additional interpretive aid for counseling.