The Oppel–Kundt Illusion and Its Relation to Horizontal-Vertical and Oblique Effects

Perception ◽  
2021 ◽  
pp. 030100662110065
Author(s):  
Klaus Landwehr
Keyword(s):  
Oblique Effect ◽  
The Other ◽  
Vertical Orientation ◽  
Horizontal Orientation ◽  
Full Circle ◽  
Original Stimulus ◽  
Vertical Part

The Oppel–Kundt illusion consists in the overestimation of the length of filled versus empty extents. Two experiments explored its relation to the horizontal-vertical illusion, which consists in the overestimation of the length of vertical versus horizontal extents, and to the oblique effect, which consists in poorer discriminative sensitivity for obliquely as opposed to horizontally or vertically oriented stimuli. For Experiment 1, Kundt’s (1863) original stimulus was rotated in steps of 45° full circle around 360°. For Experiment 2, one part of the stimulus remained at a horizontal or vertical orientation, whereas the other part was tilted 45° or 90°. The Oppel–Kundt illusion was at its maximum at a horizontal orientation of the stimulus. The illusion was strongly attenuated with L-type figures when the vertical part was empty, but not enhanced when this part was filled, suggesting that the horizontal-vertical illusion only acts on nontextured extents. There was no oblique effect.

An Experimental Investigation of In Situ Combustion in High Permeability Contrast Systems

2021 ◽  
pp. 1-13
Author(s):  
Melek Deniz Paker ◽  
Murat Cinar
Keyword(s):  
Oil Recovery ◽  
Heavy Oil ◽  
Combustion Front ◽  
Fractured Reservoirs ◽  
Front Propagation ◽  
High Permeability ◽  
Vertical Orientation ◽  
In Situ Combustion ◽  
Horizontal Orientation

Abstract A significant portion of world oil reserves reside in naturally fractured reservoirs and a considerable amount of these resources includes heavy oil and bitumen. Thermal enhanced oil recovery methods (EOR) are mostly applied in heavy oil reservoirs to improve oil recovery. In situ combustion (/SC) is one of the thermal EOR methods that could be applicable in a variety of reservoirs. Unlike steam, heat is generated in situ due to the injection of air or oxygen enriched air into a reservoir. Energy is provided by multi-step reactions between oxygen and the fuel at particular temperatures underground. This method upgrades the oil in situ while the heaviest fraction of the oil is burned during the process. The application of /SC in fractured reservoirs is challenging since the injected air would flow through the fracture and a small portion of oil in the/near fracture would react with the injected air. Only a few researchers have studied /SC in fractured or high permeability contrast systems experimentally. For in situ combustion to be applied in fractured systems in an efficient way, the underlying mechanism needs to be understood. In this study, the major focus is permeability variation that is the most prominent feature of fractured systems. The effect of orientation and width of the region with higher permeability on the sustainability of front propagation are studied. The contrast in permeability was experimentally simulated with sand of different particle size. These higher permeability regions are analogous to fractures within a naturally fractured rock. Several /SC tests with sand-pack were carried out to obtain a better understanding of the effect of horizontal vertical, and combined (both vertical and horizontal) orientation of the high permeability region with respect to airflow to investigate the conditions that are required for a self-sustained front propagation and to understand the fundamental behavior. Within the experimental conditions of the study, the test results showed that combustion front propagated faster in the higher permeability region. In addition, horizontal orientation almost had no effect on the sustainability of the front; however, it affected oxygen consumption, temperature, and velocity of the front. On the contrary, the vertical orientation of the higher permeability region had a profound effect on the sustainability of the combustion front. The combustion behavior was poorer for the tests with vertical orientation, yet the produced oil AP/ gravity was higher. Based on the experimental results a mechanism has been proposed to explain the behavior of combustion front in systems with high permeability contrast.

Naked or Clothed? Eschatology and the Doctrine of Creation

2009 ◽  
Vol 45 ◽  
pp. 1-19 ◽  
Author(s):  
Frances Young
Keyword(s):  
The Other ◽  
Early Church ◽  
Eastern Orthodox ◽  
Greek Mythology ◽  
Apocalyptic Literature ◽  
Life After Death ◽  
Full Circle ◽  
The New Testament ◽  
Doctrine Of Creation ◽  
Immortality Of The Soul

A Paper on life after death in the early church should probably begin with the underworld: Sheol in the Hebrew Bible, Hades, in Greek mythology, with parallels in ancient Mesopotamia, Egypt and Persia. It should reflect on the universally connected theme of judgment and its importance for theodicy, and address the wide variety of beliefs discernible in the New Testament and its background, especially in the apocalyptic literature. It should consider the so-called intermediate state, and the supposed distinction between the Greek concept of the immortality of the soul and the Hebrew idea of resurrection: which takes us full circle, since the latter notion assumes the picture of shades in the underworld brought back to full-bodied living – as indeed the traditional Anastasis icon of the Eastern Orthodox tradition makes dramatically clear, Christ springing up from the grave and hauling Adam up with one hand and, often though not invariably, Eve with the other.

Experimental Study on Oscillating Heat Pipe With Hydraulic Diameter Far Exceeding the Maximum Hydraulic Diameter

2019 ◽  
Author(s):  
Lilin Chu ◽  
Yulong Ji ◽  
Chunrong Yu ◽  
Yantao Li ◽  
Hongbin Ma ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Pipe ◽  
Heat Transfer Performance ◽  
Hydraulic Diameter ◽  
Working Fluid ◽  
Transfer Performance ◽  
Vertical Orientation ◽  
Oscillating Heat Pipe ◽  
Horizontal Orientation ◽  
Small Bubbles

Abstract In order to understand the heat transfer performance, startup and fluid flow condition of oscillating heat pipe (OHP) with hydraulic diameter far exceeding the maximum hydraulic diameter (MHD), an experimental investigation on heat transfer performance and visualization was conducted. From the experimental performance, it is found that the OHP can still work well with ethanol as the working fluid when the tube diameter has exceeded the MHD of 91.6%. In addition, the detailed flow patterns of the OHP were recorded by a highspeed camera for vertical and horizontal orientation to understand its physical mechanism. In the vertical orientation, initially working fluid generates small bubbles, and then the small bubbles coalesce and grow to vapor plugs, the vapor plugs finally pushes the liquid slugs to oscillate in the tube. In the horizontal orientation, the working fluid surface fluctuates due to the vapors flow from the evaporator to the condenser and bubbles burst in the evaporator. When the peak of liquid wave reaches the upper surface of tube, a liquid slug has been formed, and then the steam flow pushes the liquid slugs to oscillate in the tube.

Sand Erosion in Multiphase Flow for Low-Liquid Loading and Annular Conditions

2012 ◽  
Author(s):  
R. E. Vieira ◽  
N. R. Kesana ◽  
B. S. McLaury ◽  
S. A. Shirazi
Keyword(s):  
Multiphase Flow ◽  
Multiphase Flows ◽  
Large Scale ◽  
Flow Patterns ◽  
Production Equipment ◽  
Flow Loop ◽  
Liquid Loading ◽  
Vertical Orientation ◽  
Horizontal Orientation ◽  
Sand Erosion

Low-liquid loading (LLL) and annular gas-liquid flow patterns are commonly encountered in gas transportation pipelines. They may also occur in other off-shore production facilities such as gas/condensate production systems. Experience gained from production of hydrocarbons has shown that severe degradation of production equipment will occur due to sand entrained in gas-dominant multiphase flows. Sand erosion in multiphase flows is a complex phenomenon since several factors influence the particle impact velocity with the wall. In order to give a more comprehensive understanding of the particle erosion process in this particular scenario and to improve the current semi-mechanistic models, erosion and sand distribution measurements were conducted on 76.2 mm (3 inch) and 101.6 mm (4 inch) diameter pipes in a large scale multiphase flow loop with varying gas (air) and liquid (water) velocities generating low-liquid loading and annular conditions. Particle sizes used in the experiments were 150 and 300 microns with the latter being sharper than the former. Erosion measurements were made at sixteen different locations on a 76.2 mm (3 inch) standard elbow using ultrasonic technology, whereas Electrical Resistance (ER) probes were used for the measurements in a 101.6 mm (4 inch) diameter pipe. The experiments were primarily performed in the upward vertical orientation but a few measurements were performed in the horizontal orientation. Results suggest that the erosion is an order of magnitude higher when the pipe is oriented vertically compared to horizontal orientation. Also, the location of maximum erosion is identified for these flow patterns and it is not dependent on the pipe inclination.

scholarly journals Effect of CFRP Strips Orientation on Performance of Strengthened Deep Beams

2019 ◽  
Vol 12 (3) ◽  
Author(s):  
Ahmed Sagban Saadoon
Keyword(s):  
Carrying Capacity ◽  
Concrete Strength ◽  
Percentage Increase ◽  
Load Carrying Capacity ◽  
Deep Beams ◽  
Vertical Orientation ◽  
Horizontal Orientation ◽  
Load Carrying ◽  
Rc Deep Beams ◽  
Frp Strips

This study  was carried out in order to explore the behaviour of RC deep beams strengthening with CFRP strips. Eight simply supported deep beams were fabricated and tested under four-points loading scenario. Three different orientations for CFRP strips were used for strengthening the RC deep beams ; vertical, horizontal and inclined. All of the tested  samples were of the same dimensions, concrete strength and steel reinforcement. A percentage increase in load carrying capacity of 48, 19 and 38% (with respect to the unstrengthened beam) was gained for beams strengthened with vertical, horizontal and inclined FRP strips, respectively. It was concluded that the strengthening with FRP strips of vertical fabric orientation is more efficient than strengthening with horizontal or inclined orientation since the vertical orientation gives the highest load carrying capacity, largest deflections at ultimate load and smallest crack width. On the other hand, applied the FRP strips in  a horizontal orientation   was  insufficient for the strengthening purposes.

Text Categorisation Through Dimensionality Reduction Using Wavelet Transform

2020 ◽  
Vol 19 (04) ◽  
pp. 2050039
Author(s):  
Jorge Chamorro-Padial ◽  
Rosa Rodríguez-Sánchez
Keyword(s):  
Wavelet Transform ◽  
Dimensionality Reduction ◽  
Text Classification ◽  
High Energy ◽  
Discrete Wavelet ◽  
Wavelet Coefficients ◽  
Vertical Orientation ◽  
Method Of Dimensionality Reduction ◽  
Horizontal Orientation ◽  
Relevant Level

This paper proposes a new method of dimensionality reduction when performing Text Classification, by applying the discrete wavelet transform to the document-term frequencies matrix. We analyse the features provided by the wavelet coefficients from the different orientations: (1) The high energy coefficients in the horizontal orientation correspond to relevant terms in a single document. (2) The high energy coefficients in the vertical orientation correspond to relevant terms for a single document, but not for the others. (3) The high energy coefficients in the diagonal orientation correspond to relevant terms in a document in comparison to other terms. If we filter using the wavelet coefficients and fulfil these three conditions simultaneously, we can obtain a reduced vocabulary of the corpus, with less dimensions than in the original one. To test the success of the reduced vocabulary, we recoded the corpus with the new reduced vocabulary and we obtained a statistically relevant level of accuracy for document classification.

Visual Laterality Effects: Reexamination

1981 ◽  
Vol 52 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Michael W. Shefsky
Keyword(s):  
Decision Making ◽  
Motor Response ◽  
Cerebral Hemispheres ◽  
Detection Accuracy ◽  
Vertical Orientation ◽  
Perceptual Asymmetry ◽  
Horizontal Orientation ◽  
Simple Motor ◽  
Structural Differences ◽  
Visual Hemifields

Subjects were asked to indicate, by a simple motor response, the presence or absence of a word (signal) in unilaterally presented five-letter words and nonwords (noise). Both vertical and horizontal orientation of stimuli were employed. Detection accuracy ( d') did not differ between visual hemifields and was greater for horizontal than for vertical orientation. Decision making was more conservative for left-hemifield presentation and more conservative for vertical orientation. Models of perceptual asymmetry based on structural differences between cerebral hemispheres are weakened by the results.

Methods for Amplitude Calibration and Orientation Discrepancy Measurement: Comparing Co‐Located Sensors of Different Types in the Southern California Seismic Network

2019 ◽  
Vol 109 (4) ◽  
pp. 1563-1570 ◽  
Author(s):  
Zefeng Li ◽  
Egill Hauksson ◽  
Jennifer Andrews
Keyword(s):  
Southern California ◽  
Dynamic Range ◽  
Strong Motion ◽  
Seismic Network ◽  
Motion Sensors ◽  
Vertical Orientation ◽  
Horizontal Orientation ◽  
California Institute Of Technology ◽  
Short Period ◽  
Institute Of Technology

Abstract Modern seismic networks commonly equip a station with multiple sensors, to extend the frequency band and the dynamic range of data recorded at the station. In addition, in our recent study we showed that comparison of data from co‐located seismometers and accelerometers is useful for detecting instrument malfunctions and monitoring data quality. In this study, we extend comparison of data from different co‐located sensors to two other applications: (1) amplitude calibration for data from vertical short‐period sensors with strong‐motion sensors as baseline and (2) measurement of orientation discrepancy between strong‐motion and broadband sensors. We perform systematic analyses of data recorded by the California Institute of Technology/U.S. Geological Survey Southern California Seismic Network. In the first application, we compare the amplitude of data from vertical short‐period sensors to that of data from co‐located strong‐motion sensors and measure the amplitude calibration factors for 93 short‐period sensors. Among them, 49 stations are measured at ∼1.0, 42 measured at ∼0.6, as well as two outlying stations: GFF at 0.3 and CHI at 1.3. These values are found to be related to the sensors’ sensitivity values. In the second application, we measure orientation discrepancy between 222 co‐located broadband and strong‐motion sensors. All the vertical orientation differences are found to be within 5°. However, the horizontal orientation differences of 22 stations are greater than 6°, among which four stations have reverse rotation or 180° from the expected orientation. These measurements have been communicated to network operators and fixes are being applied. This study, together with our previously developed data monitoring framework, demonstrates that comparison of different co‐located sensors is a simple and effective tool for a broad range of seismic data assessment and instrument calibration.

An Examination of Trapped Bubbles for Viscous Drag Reduction on Submerged Surfaces

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Kelly A. Stephani ◽  
David B. Goldstein
Keyword(s):  
Drag Reduction ◽  
Flat Plate ◽  
Tap Water ◽  
Water Environment ◽  
Film Coating ◽  
Force Balance ◽  
Viscous Drag ◽  
Vertical Orientation ◽  
Drag Forces ◽  
Horizontal Orientation

Viscous drag reduction on a submerged surface can be obtained both in the limit of an unbroken gas film coating the solid and in the nanobubble or perhaps microbubble coating regime when an air layer is created with superhydrophobic coatings. We examine an intermediate bubble size regime with a trapped-bubble array (TBA) formed in a tap water environment using electrolysis to grow and maintain bubbles in thousands of millimeter-sized holes on a solid surface. We show that even though surface tension is sufficient to stabilize bubbles in a TBA against hydrostatic and shear forces beneath a turbulent boundary layer, no drag reduction is obtained. Drag measurements were acquired over Reynolds numbers based on plate length ranging from 7.2×104<ReL<3.1×105 using either a force balance for plates mounted in a vertical orientation, or by performing a momentum integral balance using a wake survey for a flat plate mounted in either vertical or horizontal orientation. In that the drag forces were small, emphasis was placed on minimizing experimental uncertainty. For comparison, the flow over a flat plate covered on one side by a large uninterrupted gas film was examined and found to produce large drag reductions of up to 32%.

Scopes of Religious Exemption

2018 ◽  
Author(s):  
Kevin Vallier ◽  
Michael Weber
Keyword(s):  
The State ◽  
The Other ◽  
Ideal Types ◽  
Full Circle ◽  
The Relationship ◽  
Range Of Values ◽  
Religious Exemption

Religious exemptions take a variety of forms, with distinct shapes and normative underpinnings. This chapter identifies eight ideal types of religious exemptions, grouped into three larger rubrics, representing different analytic and justificatory structures, to help make sense of what might otherwise seem to be mysterious discontinuities and inconsistencies. The essay suggests how the various types can illuminate each other and how surveying the sequence as a whole might say something about the relationship between religion and the state and the power of the legal imagination. The payoff is that the first, most straightforward, category of religion-based exemptions is also the most radical. Some of the other categories are tamer precisely to the extent that they introduce a wider and more complex range of values, but that the excursion in the end will necessarily come full circle to where it began, with an existential encounter between religion and the state.

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