scholarly journals Development of a Hydrodynamic Model of Puget Sound and Northwest Straits

2007 ◽  
Author(s):  
Zhaoqing Yang ◽  
Tarang P. Khangaonkar
Keyword(s):  
Hydrodynamic Model ◽  
Puget Sound

Rapid shell closure in the brachiopods Terebratulina retusa and Terebrataua transversa

1992 ◽  
Vol 72 (3) ◽  
pp. 579-598 ◽  
Author(s):  
Spafford C. Ackerly
Keyword(s):  
Detailed Analysis ◽  
Hydrodynamic Model ◽  
Puget Sound ◽  
Muscle Length ◽  
Adductor Muscle ◽  
Muscle Physiology ◽  
Shell Closure ◽  
Functional Architecture ◽  
Adductor Muscles ◽  
Kinematic Properties

Rapid shell closure in articulate brachiopods, occurring by a twitch contraction of the the ‘quick’ adductor muscles, is a response to disturbance or to physiological requirements of the organism. The relative simplicity of the closing system permits a detailed analysis of the functional architecture of the mechanism and the underlying principles of skeleto-muscular organization, in terms of (1) basic kinematic properties of the system (speeds and times of closure), (2) hydrodynamic reactions resisting closure, and (3) considerations of muscle physiology and mechanics.Analyses of shell closure in the brachiopods Terebratulina retusa from the Firth of Lorn, Scotland, and Terebratalia transversa from Puget Sound, USA, reveal (1) shell-closing times of the order of 50 to 70 ms, (2) closing velocities of the order of 3·5 radians s-1, from initial gapes of about 0·05 to 0·2 rad, and (3) muscle moment forces and hydrodynamic reactions with magnitudes of the order of 5 × 10-4 N m (5 g cm). Muscle tensions developed in the ‘quick’ adductor muscle are of the order of 105 N m2, and contraction velocities are of the order of one muscle length per second. Hydrodynamic reactions are a fundamental constraint on the closing mechanism, as determined by the concordance of actual closing events with predictions of a hydrodynamic model.

Endangered Butterflies and their Non-Native Host Plants: Examining Shifting Values of Belonging in Restoration

2019 ◽  
Vol 3 (1) ◽  
pp. 1-9
Author(s):  
Robert M. Anderson ◽  
Amy M. Lambert
Keyword(s):  
Ecological Restoration ◽  
Native Species ◽  
Puget Sound ◽  
A Value ◽  
The Social ◽  
Remote Island ◽  
Scientific Truth ◽  
Native Host

The island marble butterfly (Euchloe ausonides insulanus), thought to be extinct throughout the 20th century until re-discovered on a single remote island in Puget Sound in 1998, has become the focus of a concerted protection effort to prevent its extinction. However, efforts to “restore” island marble habitat conflict with efforts to “restore” the prairie ecosystem where it lives, because of the butterfly’s use of a non-native “weedy” host plant. Through a case study of the island marble project, we examine the practice of ecological restoration as the enactment of particular norms that define which species are understood to belong in the place being restored. We contextualize this case study within ongoing debates over the value of “native” species, indicative of deep-seated uncertainties and anxieties about the role of human intervention to alter or manage landscapes and ecosystems, in the time commonly described as the “Anthropocene.” We interpret the question of “what plants and animals belong in a particular place?” as not a question of scientific truth, but a value-laden construct of environmental management in practice, and we argue for deeper reflexivity on the part of environmental scientists and managers about the social values that inform ecological restoration.

Evaluation of Loosening and Soil Compaction with a Working Tool of Tillage Machines Using a Hydrodynamic Model

2020 ◽  
Vol 13 (6) ◽  
pp. 394
Author(s):  
Salavat Mudarisov ◽  
Ildar Farkhutdinov ◽  
Airat Mukhametdinov ◽  
Raushan Aminov ◽  
Rustam Bagautdinov ◽  
...  
Keyword(s):  
Hydrodynamic Model ◽  
Soil Compaction

UJI TARIK HIDRODINAMIKMODEL KAPAL BERSAYAP WiSE DENGAN LAMBUNG DASAR BERSTEP

2013 ◽  
Vol 12 (3) ◽  
Author(s):  
Iskendar Iskendar ◽  
Andi Jamaludin ◽  
Paulus Indiyono
Keyword(s):  
Comparative Study ◽  
Model Test ◽  
Hydrodynamic Model ◽  
Surface Effect ◽  
Center Of Gravity ◽  
Test Results ◽  
Flat Bottom ◽  
Towing Tank ◽  
Test Models ◽  
Wetted Surface Area

This paper describes hydrodynamic model tests of Wing in Surface Effect (WiSE) Craft. These craft  was fitted with  stephull  form in different location on longitudinal flat bottom (stepedhull planning craft) to determine the influences of sticking and porpoising motion performances. These motions are usually occured when the craft start to take-off from water surfaces. The test models with scale of 1 : 7 were comprised of 4 (four) stephull models and 1 (one) non-stephull model  as a comparative study. The hydrodynamic  tests were performed with craft speed of 16 – 32 knots (prototype values) in Towing Tank at UPT. Balai Pengkajian dan Penelitian Hidrodinamika (BPPH), BPPT, Surabaya. The resistance (drag) was measured by dynamo meter and the trim of model (draft changing at fore and aft  of model due to model speed) was measured by trim meter. By knowing the value of model trim, the wetted surface area can be determined. Then, the lift forces were calculated based on these measured values. The model test results were presented on tables and curves.  Test results show that models  with step located far away from center of gravity of the WiSE craft tend to porpoising and sticking condition, except if the step location on the below of these center of gravity. While model without step tends to sticking conditions.

Otolith research for Puget Sound

Fact Sheet ◽  
2007 ◽  
Author(s):  
K. Larsen ◽  
R. Reisenbichler
Keyword(s):  
Puget Sound
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