scholarly journals ROLE OF PHYSICAL MODELLING IN DEVELOPING A NEW CRUISE SHIP TERMINAL AT AN EXPOSED SITE

2014 ◽  
Vol 1 (34) ◽  
pp. 80
Author(s):  
Paul Knox ◽  
Dave Anglin ◽  
Andrew Cornett ◽  
Erin Hall ◽  
Mathew Armstrong
Keyword(s):  
Physical Modelling ◽  
Cruise Ship ◽  
Exposed Site

scholarly journals Effect of Variations in Water Level and Wave Steepness on the Robustness of Wave Overtopping Estimation

2020 ◽  
Vol 8 (2) ◽  
pp. 63
Author(s):  
Nils B. Kerpen ◽  
Karl-Friedrich Daemrich ◽  
Oliver Lojek ◽  
Torsten Schlurmann
Keyword(s):  
Water Level ◽  
Wave Spectrum ◽  
Water Environment ◽  
Physical Modelling ◽  
Storm Surges ◽  
Water Levels ◽  
Coastal Protection ◽  
Wave Steepness ◽  
Wave Overtopping

The wave overtopping discharge at coastal defense structures is directly linked to the freeboard height. By means of physical modelling, experiments on wave overtopping volumes at sloped coastal structures are customarily determined for constant water levels and static wave steepness conditions (e.g., specific wave spectrum). These experiments are the basis for the formulation of empirically derived and widely acknowledged wave overtopping estimations for practical design purposes. By analysis and laboratory reproduction of typical features from exemplarily regarded real storm surge time series in German coastal waters, the role of non-stationary water level and wave steepness were analyzed and adjusted in experiments. The robustness of wave overtopping estimation formulae (i.e., the capabilities and limitations of such a static projection of dynamic boundary conditions) are outlined. Therefore, the classic static approach is contrasted with data stemming from tests in which both water level and wave steepness were dynamically altered in representative arrangements. The analysis reveals that mean overtopping discharges for simple sloping structures in an almost deep water environment could be robustly estimated for dynamic water level changes by means of the present design formulae. In contrast, the role of dynamic changes of the wave steepness led to a substantial discrepancy of overtopping volumes by a factor of two. This finding opens new discussion on methodology and criteria design of coastal protection infrastructure under dynamic exposure to storm surges and in lieu of alterations stemming from projected sea level rise.

Mathematical and physical modelling of doublediffusive convection of aqueous solutions crystallizing at a vertical wall

1988 ◽  
Vol 187 ◽  
pp. 409-433 ◽  
Author(s):  
Mollie E. Thompson ◽  
Julian Szekely
Keyword(s):  
Vertical Wall ◽  
Physical Modelling ◽  
Double Diffusion ◽  
Liquid Region ◽  
Carbonate Solutions ◽  
Aqueous Sodium Carbonate ◽  
Lateral Temperature ◽  
Theory And Experiments ◽  
Stratified Liquid

Solidification of a double-diffusive liquid from a vertical wall in a rectangular cavity is investigated using both mathematical and physical modelling. A two-dimensional mathematical model is developed to simulate the process of solidification in a two-component liquid containing a denser solute. Observations on the solidification behaviour of aqueous sodium carbonate solutions are used to verify the results of the mathematical analysis. The theory and experiments provide a clear picture of the role of double-diffusion in producing vertical compositional and density stratification in an initially homogeneous liquid during solidification. The development of horizontally oriented convection cells in the stratified liquid is correlated with the magnitude of the destabilizing lateral temperature difference across the liquid region.

scholarly journals Dynamics of the Bacillus subtilis Min system

2020 ◽  
Author(s):  
Helge Feddersen ◽  
Laeschkir Würthner ◽  
Erwin Frey ◽  
Marc Bramkamp
Keyword(s):  
Bacillus Subtilis ◽  
Active Sites ◽  
Dynamic Equilibrium ◽  
Model Organism ◽  
Physical Modelling ◽  
Division Site ◽  
Diffusion Constants ◽  
Dynamic Equilibrium State ◽  
Min Proteins

SummaryDivision site selection is a vital process to ensure generation of viable offspring. In many rod-shaped bacteria a dynamic protein system, termed the Min system, acts as a central regulator of division site placement. The Min system is best studied in Escherichia coli where it shows a remarkable oscillation from pole to pole with a time-averaged density minimum at midcell. Several components of the Min system are conserved in the Gram-positive model organism Bacillus subtilis. However, in B. subtilis it is believed that the system forms a stationary bipolar gradient from the cell poles to midcell. Here, we show that the Min system of B. subtilis localizes dynamically to active sites of division, often organized in clusters. We provide physical modelling using measured diffusion constants that describe the observed enrichment of the Min system at the septum. Modelling suggests that the observed localization pattern of Min proteins corresponds to a dynamic equilibrium state. Our data provide evidence for the importance of ongoing septation for the Min dynamics, consistent with a major role of the Min system to control active division sites, but not cell pole areas.

Optimization of the performance of hoppered peripheral-feed clarifiers

1996 ◽  
Vol 33 (8) ◽  
pp. 125-133
Author(s):  
Z. Phiri ◽  
Y. Saito ◽  
Bakri Bin Ishak ◽  
H. Harada ◽  
S. Nakajima
Keyword(s):  
Developing Countries ◽  
Physical Modelling ◽  
Nozzle Diameter ◽  
Hydraulic Efficiency ◽  
Spiral Flow ◽  
Technical Performance ◽  
Global Geometry ◽  
Overall Performance ◽  
Solids Removal

The tide of “development” gathering pace in developing countries has resulted in the production of increasing quantities of wastewaters. This inevitably necessitates a reappraisal/reassessment of wastewater technologies. This study demonstrates the role of simple physical modelling approaches in evaluating/appraising the technical performance of hoppered peripheral-feed (spiral-flow) clarifiers -- which clarifiers have enormous scope for use in small plants in developing countries. The study focuses on the optimization of local geometrics and hydrodynamics for the purposes of improving overall performance in hoppered spiral flow clarifiers. It is concluded that for a defined set of clarifier global geometry and loading conditions, an optimum race width and inlet nozzle diameter exist. The optimum values of these parameters for a defined conceptual prototype are presented. It is further concluded that the mere variation of either the race width or the inlet nozzle diameter significantly affects the hydraulic detention and solids removal interrelationships in hoppered spiral flow clarifiers. Under the conditions of this study, a 50% reduction in inlet nozzle diameter resulted in an incredible more than 50% loss in hydraulic efficiency. Overall, the possibility of significantly increasing clarifier capacity and/or overall performance by simply optimizing local geometrics and hydrodynamics has been demonstrated via a well tested and friendly methodology.

scholarly journals (A168) Medicine at Sea

2011 ◽  
Vol 26 (S1) ◽  
pp. s48-s48
Author(s):  
J. Bradberry ◽  
J. Fisher
Keyword(s):  
Tourist Industry ◽  
Cruise Ship ◽  
Health Measures ◽  
Cruise Ships ◽  
Wide Range ◽  
Major Incidents ◽  
Medical Emergencies ◽  
Medical Teams ◽  
Psychiatric Issues

Cruising has become a major part of the tourist industry. In 2010, the total passengers carried worldwide was estimated at 18.4 million, on about 230 cruise ships. Large ships can hold up to 6,000 passengers and > 2,000 crew members. A large cruise ship is rather like an island, with two different communities: the well-trained crew, hopefully prepared for every eventuality and trying to make their guest's stay as pleasant as possible; and the guests, there to have fun. The guest population varies, with up to 40% under 21 years old during school breaks, and the average age is in the fifties or sixties on longer cruises to scenic places such as Alaska. Most of the time ships cannot be reached by helicopter and the medical teams need to cope with a wide range of emergencies from cardiopulmonary, trauma, and psychiatric issues. There are strict public health measures enforced and a range of legislation reducing the risks of cruising to a minimum. This paper reviews the training of the crew for medical emergencies, the incidence of disease, the incidence of medical disembarkation and major incidents on board, and the role of medical teams.

Twenty years of systematic physical geography: issues for a 'New Environmental Age'

1992 ◽  
Vol 16 (2) ◽  
pp. 209-221 ◽  
Author(s):  
Malcolm Newson
Keyword(s):  
Environmental Science ◽  
Systems Approach ◽  
Physical Modelling ◽  
Physical Geography ◽  
Natural Systems ◽  
The Social ◽  
The Subject ◽  
The Uk ◽  
Or Applications

This review assesses the role of physical geography in the 'New Environmental Age'; it addresses especially the role of the natural systems approach after 20 years in which this has constituted the main fabric of physical geography in the UK. It also necessarily examines the role of geomorphology, the dominant partner in British physical geography, in positioning the subject as an environmental science. Systems thinking has clearly pervaded pedagogic aspects of physical geography but its full holistic methodology has not provided a coherent disciplinarity in research or applications. A holistic, conservationist perspective has often been disowned by physical geographers, leaving professional environmental applications largely in the hands of applied geomor phology. Now, however, there are major opportunities for a broader physical geography, especially one prepared to re-espouse the social science and humanities aspects of geography whose knowledge-base is so essential to the environmental manager's 'scenario-setting' (as opposed to pure physical modelling). Breadth-versus-depth arguments seem, however, likely to continue in physical geography, with those favouring breadth necessarily becoming environmentalists whilst those retaining depth become less preoccupied by equilibrium conditions of systems, stressing instead discontinuity and natural hiatuses.

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