Modeling the Impacts of Urbanization and Open Water Surface on Heavy Convective Rainfall: A Case Study over the Emerging Xiong'an City, China

Conventionally, the stopping of a ship is achieved by direct reversal of propeller rotation. However, the introduction of azimuthing pods presents other options. The following study examines the various modes that may be employed to stop a pod-driven ship. A continuous function is derived describing the hydrodynamic forces on both the propeller and the pod body for any load condition and helm angle, including fluid damping and added mass effects. The proposed function is validated through comparison with comprehensive open water model tests. Next, a time domain simulation algorithm is proposed to examine the dynamic effects including the mass inertia on both the propeller shaft and slewing stock. Finally, a simulation study for the proposed stopping modes is performed using a known design as a case study. Results and discussion are presented.

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A CASE STUDY ON THROUGH-WATER DENSE IMAGE MATCHING

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-2-659-2018 ◽

2018 ◽

Vol XLII-2 ◽

pp. 659-666 ◽

Cited By ~ 5

Author(s):

G. Mandlburger

Keyword(s):

Image Matching ◽

Water Surface ◽

Point Clouds ◽

Water Clarity ◽

Aerial Images ◽

Mean Deviation ◽

Range Image ◽

Surface Mapping ◽

Dense Image

In the last years, the tremendous progress in image processing and camera technology has reactivated the interest in photogrammetrybased surface mapping. With the advent of Dense Image Matching (DIM), the derivation of height values on a per-pixel basis became feasible, allowing the derivation of Digital Elevation Models (DEM) with a spatial resolution in the range of the ground sampling distance of the aerial images, which is often below 10&thinsp;cm today. While mapping topography and vegetation constitutes the primary field of application for image based surface reconstruction, multi-spectral images also allow to see through the water surface to the bottom underneath provided sufficient water clarity. In this contribution, the feasibility of through-water dense image matching for mapping shallow water bathymetry using off-the-shelf software is evaluated. In a case study, the SURE software is applied to three different coastal and inland water bodies. After refraction correction, the DIM point clouds and the DEMs derived thereof are compared to concurrently acquired laser bathymetry data. The results confirm the general suitability of through-water dense image matching, but sufficient bottom texture and favorable environmental conditions (clear water, calm water surface) are a preconditions for achieving accurate results. Water depths of up to 5&thinsp;m could be mapped with a mean deviation between laser and trough-water DIM in the dm-range. Image based water depth estimates, however, become unreliable in case of turbid or wavy water and poor bottom texture.

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Anthropometric and Physiological Responses to Prolonged Open Water Rowing: A Case Study

Journal of Human Performance in Extreme Environments ◽

10.7771/2327-2937.1028 ◽

2003 ◽

Vol 7 (2) ◽

Author(s):

Dan A. Gordon

Keyword(s):

Physiological Responses ◽

Open Water

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Landsat thermal infrared to detect sub-canopy riparian flooding

10.5194/egusphere-egu21-13762 ◽

2021 ◽

Author(s):

Emanuel Storey ◽

Witold Krajewski ◽

Efthymios Nikolopoulos

Keyword(s):

Open Water ◽

Thermal Infrared ◽

Short Wave ◽

Mapping Technique ◽

Landsat 8 ◽

Infrared Observations ◽

Plant Canopies ◽

Multi Temporal ◽

Flood Detection

Satellite based flood detection can enhance understanding of risk to humans and infrastructures, geomorphic processes, and ecological effects.&#160; Such application of optical satellite imagery has been mostly limited to the detection of water exposed to sky, as plant canopies tend to obstruct water visibility in short electromagnetic wavelengths.&#160; This case study evaluates the utility in multi-temporal thermal infrared observations from Landsat 8 as a basis for detecting sub-canopy fluvial inundation resulting in ambient temperature change.We selected three flood events of 2016 and 2019 along sections of the Mississippi, Cedar, and Wapsipinicon Rivers located in Iowa, Minnesota, and Wisconsin, United States.&#160; Classification of sub-canopy water involved logical, threshold-exceedance criteria to capture thermal decline within channel-adjacent vegetated zones.&#160; Open water extent in the floods was mapped based on short-wave infrared thresholds determined parametrically from baseline (non-flooded) observations.&#160; Map accuracy was evaluated using higher-resolution (0.5&#8211;5.0 m) synchronic optical imagery.Results demonstrate improved ability to detect sub-canopy inundation when thermal infrared change is incorporated: sub-canopy flood class accuracy was comparable to that of open water in previous studies.&#160; The multi-temporal open-water mapping technique yielded high accuracy as compared to similar studies.&#160; This research highlights the utility of Landsat thermal infrared data for monitoring riparian inundation and for validating other remotely sensed and simulated flood maps.

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Case Study of Transient Dynamics in a Bypass Reach

Water ◽

10.3390/w12061585 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1585

Author(s):

Anton J. Burman ◽

Anders G. Andersson ◽

J. Gunnar I. Hellström ◽

Kristian Angele

Keyword(s):

Water Surface ◽

Operating Conditions ◽

Surface Elevation ◽

Water Surface Elevation ◽

Positive Effects ◽

Downstream Distance ◽

Hydropower Plants ◽

Wetted Area ◽

Bed Stability

The operating conditions of Nordic hydropower plants are expected to change in the coming years to work more in conjunction with intermittent power production, causing more frequent hydropeaking events. Hydropeaking has been shown to be detrimental to wildlife in the river reaches downstream of hydropower plants. In this work, we investigate how different possible future hydropeaking scenarios affect the water surface elevation dynamics in a bypass reach in the Ume River in northern Sweden. The river dynamics has been modeled using the open-source solver Delft3D. The numerical model was validated and calibrated with water-surface-elevation measurements. A hysteresis effect on the water surface elevation, varying with the downstream distance from the spillways, was seen in both the simulated and the measured data. Increasing the hydropeaking rate is shown to dampen the variation in water surface elevation and wetted area in the most downstream parts of the reach, which could have positive effects on habitat and bed stability compared to slower rates in that region.

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Pacing and Mood Changes While Crossing the Adriatic Sea From Italy to Albania: A Case Study

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2014-0264 ◽

2015 ◽

Vol 10 (4) ◽

pp. 520-523 ◽

Cited By ~ 7

Author(s):

Giulia De Ioannon ◽

Giuseppe Cibelli ◽

Sergio Mignardi ◽

Agnese Antonelli ◽

Laura Capranica ◽

...

Keyword(s):

Perceived Exertion ◽

Adriatic Sea ◽

Mood State ◽

Open Water ◽

Fold Increase ◽

Rating Of Perceived Exertion ◽

Anthropometric Parameters ◽

Stroke Length ◽

Pacing Strategy

Purpose:To evaluate the pacing strategy, rating of perceived exertion (RPE), and mood during a 78.1-km solo ultraendurance open-water swim.Methods:Before and after the event, anthropometric parameters, cortisol, and the profile of mood state (POMS) of 1 male athlete (age 48 y, height 172 cm, body mass 68 kg, body fat 7.2%, athletic achievement: Italian record holder of the Channel Swim) were ascertained. Every 3 h during the event, average swimming speed (SS), stroke rate, stroke length (SL), and RPE were recorded.Results:The athlete completed the event in 23:44 h:min. Compared with the first 3 h of swimming, decreases in SS (−33%) and SL (−25%) were observed between 18 h and 21 h. Thereafter, the athlete increased SS (+41%) and SL (+17%) between 21 h and the end. RPE steadily increased from the beginning to the last 6 h of swimming. Cortisol showed a 23-fold increase. After the event, POMS showed a 500% increase in fatigue, 44% decrease in tension, and 77% decrease in vigor.Conclusion:For the first time ever an athlete crossed the Adriatic Sea. This case study shows that the athlete adopted a variable pacing strategy to complete 78 km. Despite the athlete perceiving his effort at maximum during the last 6 h, the observed increases in SS at the end of the event might substantiate his high potential motivation to accomplish this challenging and unique event.

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THE ANALYSIS FORMULATION OF THE LOWEST ASTRONOMICAL TIDE (LAT) BASED ON THE TIME OBSERVATION (THE CASE STUDY OF BENOA WATERS)

JOURNAL ASRO ◽

10.37875/asro.v11i1.205 ◽

2020 ◽

Vol 11 (1) ◽

pp. 77

Author(s):

Okol Sri Suharyo ◽

Johar Setiadi ◽

Nawanto Budi Sukoco ◽

Kuncoro Kuncoro

Keyword(s):

Water Surface ◽

Statistical Approach ◽

High Water ◽

Astronomical Tide ◽

Time Observation ◽

Using Data ◽

One Year ◽

Definition Of

According to the definition of International Hydrographic Organization (IHO) M-13 2005, the LowestAstronomical Tide (LAT) is Internationally used as chart datum, which is used as instruction for measuring thevalidation of high water surface in the Hydro-oceanography survey. It is predicted by tide prediction for 18.61years. This research is observed minimized in one year. In determining of LAT, it will be analyzed by the tideConstanta and prediction analysis.The analysis of tide Constanta will be calculated by the Rayleigh numberingmethod (the smallest quadrat), start on tide data observation for one month, two months, three months, fourmonths, six months until twelve months data of tide observation. Afterward, from that analysis results of t ideConstanta, it can be predicted the tide for 18.61 years. From this result, the prediction will be found thedifference of the LAT value of tide data less than in one year with tide data in one year. Then, from thedifference of LAT values can be analyzed at a significant level by using the statistical approach. From the resultof the LAT calculation by using data observation of tide in one year will be got the LAT position that is 43.3 cm.If comparing with LAT value which uses a variety of data less than in one year, it will result in the level ofsignificant differences. In this case, LAT value thas is calculated by data less than in one year cannot beequated with LAT which is used by observation of tide data in one year.Keywords: LAT, Tide Component, and interval of tide observation.

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