From the Straight path to the narrow way

Composites made from E-glass/epoxy or aramid/epoxy are frequently used in aircraft and aerospace industries. These materials are prone to suffer from the presence of delamination, which can reduce severely the performance of aircrafts and even threaten their safety. Since electric conductivity of these composites is rather small, they can propagate electromagnetic waves. Detection of delamination damage can then be monitored by using an electromagnetic penetrating radar scanner, which consists of emitting waves having the form of short time pulses that are centered on a given work frequency. While propagating, these waves undergo partial reflection when running into an obstacle or a material discontinuity. Habitually, the radar is moved at constant speed along a straight path and the reflected signal is processed as a radargram that gives the reflected energy as function of the two-way time and the antenna position.In this work, modeling of electromagnetic wave propagation in composites made from E-glass/epoxy was performed analytically. The electromagnetic wave reflection from a delamination defect was analyzed as function of key intervening factors which include the defect extent and depth, as well as the work frequency. Various simulations were performed and the obtained results have enabled to correlate the reflection pattern image features to the actual delamination defect characteristics which can provide quantification of delamination.

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The Straight Path (الصراط المستقيم)

10.31219/osf.io/9cq74 ◽

2020 ◽

Author(s):

Abdella Yimam Ali

Keyword(s):

Straight Path

This paper presents the author perception of the straight path that leads to the light (Nur) of Allah (a physical star on earth).

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Sirat al-Mustaqim and Hikma

American Journal of Islam and Society ◽

10.35632/ajis.v16i2.2129 ◽

1999 ◽

Vol 16 (2) ◽

pp. 55-87

Author(s):

Salah El-Sheikh

Keyword(s):

Rational Approach ◽

Appropriate Use ◽

Straight Path ◽

Free Environment

This paper seeks to understand the context in which the debates concerning Islamic economics are taking place. The author contends that in the absence of a democratic and free environment the discourses on Islamic economics are suffering from free and open discussions about the true essence of Islam and its implications in the socioeconomic arena. After discussing some of the limits of the discourses on Islamic economics, suc.h as a lack of common terminology and appropriate use of Qur'anic terms, the author advances his understanding of the Qur'anic approach to iman. The author argues that 'aql and hikrrui are the cornerstones of Islam and the two faculties that the Qur'an repeatedly invokes in order that humanity may understand Islamic laws and principles and fulfill its mandate of Allah's vicegerency. The paper concludes that the straight path is essentially a rational approach and invites the discourses on Islamic economics to rely more on 'aql and hikrrui in their contemplation.

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Straying from the Straight Path

10.2307/j.ctvw04jdt ◽

2017 ◽

Cited By ~ 1

Keyword(s):

Straight Path

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Electrons on a straight path: A novel ionisation vacuum gauge suitable as reference standard

Vacuum ◽

10.1016/j.vacuum.2021.110239 ◽

2021 ◽

Vol 189 ◽

pp. 110239

Author(s):

Karl Jousten ◽

Matthias Bernien ◽

Frédéric Boineau ◽

Nenad Bundaleski ◽

Claus Illgen ◽

...

Keyword(s):

Reference Standard ◽

Vacuum Gauge ◽

Straight Path

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Effect of Mean Velocity-to-Critical Velocity Ratios on Bed Topography and Incipient Motion in a Meandering Channel: Experimental Investigation

Water ◽

10.3390/w13070883 ◽

2021 ◽

Vol 13 (7) ◽

pp. 883

Author(s):

Nargess Moghaddassi ◽

Seyed Habib Musavi-Jahromi ◽

Mohammad Vaghefi ◽

Amir Khosrojerdi

Keyword(s):

Experimental Investigation ◽

Critical Velocity ◽

Velocity Ratio ◽

Scour Depth ◽

Incipient Motion ◽

Mean Velocity ◽

Straight Path ◽

Meandering Channel ◽

Bed Topography ◽

The Mean

As 180-degree meanders are observed in abundance in nature, a meandering channel with two consecutive 180-degree bends was designed and constructed to investigate bed topography variations. These two 180-degree mild bends are located between two upstream and downstream straight paths. In this study, different mean velocity-to-critical velocity ratios have been tested at the upstream straight path to determine the meander’s incipient motion. To this end, bed topography variations along the meander and the downstream straight path were addressed for different mean velocity-to-critical velocity ratios. In addition, the upstream bend’s effect on the downstream bend was investigated. Results indicated that the maximum scour depth at the downstream bend increased as a result of changing the mean velocity-to-critical velocity ratio from 0.8 to 0.84, 0.86, 0.89, 0.92, 0.95, and 0.98 by, respectively, 1.5, 2.5, 5, 10, 12, and 26 times. Moreover, increasing the ratio increased the maximum sedimentary height by 3, 10, 23, 48, 49, and 56 times. The upstream bend’s incipient motion was observed for the mean velocity-to-critical velocity ratio of 0.89, while the downstream bend’s incipient motion occurred for the ratio of 0.78.

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