WHEN IS WATER SHALLOW?

2021 ◽  
Vol 155 (A3) ◽  
Author(s):  
A Robbins ◽  
G Thomas ◽  
G Macfarlane ◽  
I Dand ◽  
M Renilson
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Performance Indicators ◽  
Wave Decay ◽  
Specific Performance ◽  
Wave Angle ◽  
Definition Of

A master of a vessel must at all times know where their vessel is operating. Traditionally this is only thought of in the geographical sense; however, there is a clear necessity, for safe vessel operations, that the master knows where their vessel is in the hydrodynamic sense. This knowledge is also of prime interest to designing naval architects and route planners alike. Water depth has profound effects on vessel performance and to know When is Water Shallow? is the key to successful vessel operation and wash mitigation. The authors propose a series of characterisations to aid the definition of shallow-water and hence provide greater operational understanding. These characterisations cover typical vessel performance indicators such as resistance, propulsion, manoeuvring, etc., but also wash-specific performance indicators such as wave angle, wave decay, soliton occurrence and spectral output.

When is water shallow?

2013 ◽  
Vol 155 (A3) ◽  
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Performance Indicators ◽  
Wave Decay ◽  
Specific Performance ◽  
Wave Angle ◽  
Definition Of

A master of a vessel must at all times know where their vessel is operating. Traditionally this is only thought of in the geographical sense; however, there is a clear necessity, for safe vessel operations, that the master knows where their vessel is in the hydrodynamic sense. This knowledge is also of prime interest to designing naval architects and route planners alike. Water depth has profound effects on vessel performance and to know When is Water Shallow? is the key to successful vessel operation and wash mitigation. The authors propose a series of characterisations to aid the definition of shallow-water and hence provide greater operational understanding. These characterisations cover typical vessel performance indicators such as resistance, propulsion, manoeuvring, etc., but also wash-specific performance indicators such as wave angle, wave decay, soliton occurrence and spectral output.

Contract Growing for the Export-oriented Cut Flowers Industry in Turkey

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 531a-531 ◽  
Author(s):  
Robin G. Brumfield ◽  
Burhan Ozkan ◽  
Osman Karagüzel
Keyword(s):  
Performance Indicators ◽  
Price Setting ◽  
Production Structure ◽  
Cut Flower ◽  
Cut Flowers ◽  
Product Price ◽  
Plant Materials ◽  
Flower Production ◽  
Specific Performance ◽  
Insight Into

Thirty cut flower businesses were surveyed in 1997 to examine the production structure and main problems of export-oriented contract growing in Turkey. The survey was conducted in Antalya province, which is the center of export-oriented cut flower production in Turkey. The results of the research provided insight into how Turkish cut flower-contracted growers were managing some of the key areas of their operations. The study also provided the opportunity for growers to highlight their concerns about contract growing for export-oriented cut flower production. The survey showed that contract growers do not use specific performance indicators relevant to cut flower production. The product price received by the contract growers was determined by the export companies. These export companies receive flowers from growers mainly on consignment. After exporting the products, exporters periodically pay the grower, subtracting a commission for their services and other marketing expenses. Contract growers are essentially price takers in the transactions. The business procedure from production to price setting and marketing was not in the hands of the contract growers. Therefore, the trading risks are essentially borne by the contract growers. The main concerns raised by contract growers were the current consignment system, cost of the plant materials, and the late payment for the sold products.

Assessment of the Culture of Care working with laboratory animals by using a comprehensive survey tool

2021 ◽  
pp. 002367722110144
Author(s):  
Thomas Bertelsen ◽  
Kirstine Øvlisen
Keyword(s):  
Performance Indicators ◽  
Essential Elements ◽  
Laboratory Animals ◽  
Survey Tool ◽  
Culture Of Care ◽  
Eu Directive ◽  
Comprehensive Picture ◽  
Comprehensive Survey ◽  
Definition Of ◽  
The Eu

The term Culture of Care, within the scientific community using laboratory animals, is being used more and more frequently after it was introduced in the EU Directive 2010/63/EU, where it is phrased as a ‘climate of care’, which became effective in national legislation from January 2013. However, there is a risk that the term could become a meaningless phrase if no agreed local definition of the term exists at the animal facility (called establishment in the EU Directive). This paper presents a comprehensive survey tool that provides a means to describe what the Culture of Care in an establishment looks like. The tool is one of the elements that can contribute to the overall picture of the culture; however, it cannot stand alone. Together with an evaluation of the effectiveness of the Culture of Care (e.g. key performance indicators) and a description of the outcomes and achievements in terms of animal welfare and the 3Rs (Replace, Reduce, Refine), the survey tool will constitute a comprehensive picture. The survey tool offers a multilevel and comprehensive view of different subcultures, presenting details on mindset and behaviour of the employees and the different relations within the culture, thus enabling the initiation of improvement projects if required. The tool addresses essential elements of a co-operative culture in terms of what we think, what we do and how we work together.

Systematic Literature Review on Smart Mobility: A Framework for Future “Quantitative” Developments

2021 ◽  
pp. 088541222199424
Author(s):  
Mauro Francini ◽  
Lucia Chieffallo ◽  
Annunziata Palermo ◽  
Maria Francesca Viapiana
Keyword(s):  
Cluster Analysis ◽  
Literature Review ◽  
Systematic Literature Review ◽  
Performance Indicators ◽  
State Of The Art ◽  
Measurement Model ◽  
Broader Impacts ◽  
Research Goal ◽  
Smart Mobility ◽  
Definition Of

This work aims to reorganize theoretical and empirical research on smart mobility through the systematic literature review approach. The research goal is to reach an extended and shared definition of smart mobility using the cluster analysis. The article provides a summary of the state of the art that can have broader impacts in determining new angles for approaching research. In particular, the results will be a reference for future quantitative developments for the authors who are working on the construction of a territorial measurement model of the smartness degree, helping them in identifying performance indicators consistent with the definition proposed.

Resistance Tests of an Articulated Pusher Barge System in Deep and Shallow Water

2021 ◽  
Author(s):  
Li Zhang ◽  
Lei Xing ◽  
Mingyu Dong ◽  
Weimin Chen
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Deep Water ◽  
Water Resistance ◽  
Model Tests ◽  
System 2 ◽  
Changing Trend ◽  
The Difference ◽  
Transport Vessel ◽  
Resistance Performance

Abstract Articulated pusher barge vessel is a short-distance transport vessel with good economic performance and practicability, which is widely used in the Yangtze River of China. In this present work, the resistance performance of articulated pusher barge vessel in deep water and shallow water was studied by model tests in the towing tank and basin of Shanghai Ship and Shipping Research Institute. During the experimental investigation, the articulated pusher barge vessel was divided into three parts: the pusher, the barge and the articulated pusher barge system. Firstly, the deep water resistance performance of the articulated pusher barge system, barge and the pusher at design draught T was studied, then the water depth h was adjusted, and the shallow water resistance at h/T = 2.0, 1.5 and 1.2 was tested and studied respectively, and the difference between deep water resistance and shallow water resistance at design draught were compared. The results of model tests and analysis show that: 1) in the study of deep water resistance, the total resistance of the barge was larger than that of the articulated pusher barge system. 2) for the barge, the shallow water resistance increases about 0.4–0.7 times at h/T = 2.0, 0.5–1.1 times at h/T = 1.5, and 0.7–2.3 times at h/T = 1.2. 3) for the pusher, the shallow water resistance increases about 1.0–0.4 times at h/T = 2.7, 1.2–0.9 times at h/T = 2.0, and 1.7–2.4 times at h/T = 1.6. 4) for the articulated pusher barge system, the shallow water resistance increases about 0.2–0.3 times at h/T = 2.0, 0.5–1.3 times at h/T = 1.5, and 1.0–3.5 times at h/T = 1.2. Furthermore, the water depth Froude number Frh in shallow water was compared with the changing trend of resistance in shallow water.

Stability of offshore structures in shallow water depth

2011 ◽  
Vol 2 (2) ◽  
pp. 320-333
Author(s):  
F. Van den Abeele ◽  
J. Vande Voorde
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Fossil Fuels ◽  
Oil And Gas ◽  
Structural Response ◽  
Offshore Structures ◽  
Exploration And Production ◽  
Subsea Pipelines ◽  
Wave Induced ◽  
Shallow Water Depth

The worldwide demand for energy, and in particular fossil fuels, keeps pushing the boundaries of offshoreengineering. Oil and gas majors are conducting their exploration and production activities in remotelocations and water depths exceeding 3000 meters. Such challenging conditions call for enhancedengineering techniques to cope with the risks of collapse, fatigue and pressure containment.On the other hand, offshore structures in shallow water depth (up to 100 meter) require a different anddedicated approach. Such structures are less prone to unstable collapse, but are often subjected to higherflow velocities, induced by both tides and waves. In this paper, numerical tools and utilities to study thestability of offshore structures in shallow water depth are reviewed, and three case studies are provided.First, the Coupled Eulerian Lagrangian (CEL) approach is demonstrated to combine the effects of fluid flowon the structural response of offshore structures. This approach is used to predict fluid flow aroundsubmersible platforms and jack-up rigs.Then, a Computational Fluid Dynamics (CFD) analysis is performed to calculate the turbulent Von Karmanstreet in the wake of subsea structures. At higher Reynolds numbers, this turbulent flow can give rise tovortex shedding and hence cyclic loading. Fluid structure interaction is applied to investigate the dynamicsof submarine risers, and evaluate the susceptibility of vortex induced vibrations.As a third case study, a hydrodynamic analysis is conducted to assess the combined effects of steadycurrent and oscillatory wave-induced flow on submerged structures. At the end of this paper, such ananalysis is performed to calculate drag, lift and inertia forces on partially buried subsea pipelines.

Experimental Investigation of Trimaran Models in Shallow Water

2014 ◽  
Vol 30 (02) ◽  
pp. 66-78
Author(s):  
Mark Pavkov ◽  
Morabito Morabitob
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Critical Speed ◽  
Water Effect ◽  
Finite Water Depth ◽  
Speed Regime ◽  
Displacement Speed ◽  
Littoral Combat Ship ◽  
Shallow Water Effect ◽  
The U.S

Experiments were conducted at the U.S. Naval Academy's Hydromechanics Laboratory to determine the effect of finite water depth on the resistance, heave, and trim of two different trimaran models. The models were tested at the same length to water depth ratios over a range of Froude numbers in the displacement speed regime. The models were also towed in deep water for comparison. Additionally, the side hulls were adjusted to two different longitudinal positions to investigate possible differences resulting from position. Near critical speed, a large increase in resistance and sinkage was observed, consistent with observations of conventional displacement hulls. The data from the two models are scaled up to a notional 125-m length to illustrate the effects that would be observed for actual ships similar in size to the U.S. Navy's Independence Class Littoral Combat Ship. Faired plots are developed to allow for rapid estimation of shallow water effect on trimaran resistance and under keel clearance. An example is provided.

scholarly journals ADDED MASSES OF LARGE TANKERS BERTHING TO DOLPHINS

1976 ◽  
Vol 1 (15) ◽  
pp. 161 ◽  
Author(s):  
Taizo Hayashi ◽  
Masujiro Shirai
Keyword(s):  
Shallow Water ◽  
Froude Number ◽  
Water Depth ◽  
Head Loss ◽  
Theoretical Formula ◽  
Counter Flow ◽  
Added Masses ◽  
Mass Factor ◽  
Large Vessels ◽  
Good Agreement

The added masses of large tankers berthing to dolphins are studied both theoretically and experimentally. The movements of large vessels in shallow water in the directions normal to their planes of symmetry cause counterflows of appreciable velocities under the hulls. The inertia of these counter-flows is shown to have an important effect on the added masses of the vessels. A theoretical formula is derived to determine the mass factor of an ocean vessel in shallow water as a function of the ratio Draught/Water- depth, the Froude number of the vessel and the coefficient of head loss of the counter-flow under the hull. Experiment is made to determine the mass factor. Comparison:, between the theory and the experiment shows a good agreement.

Validation of Wave Propagation in Numerical Wave Tanks

2005 ◽  
Author(s):  
Tim Bunnik ◽  
Rene´ Huijsmans
Keyword(s):  
Shallow Water ◽  
Model Test ◽  
Water Depth ◽  
Linear Potential ◽  
Intermediate Water ◽  
Numerical Wave Tank ◽  
Wave Tank ◽  
Type Wave ◽  
Wave Generator ◽  
Numerical Wave

During the last few years there has been a strong growth in the availability and capabilities of numerical wave tanks. In order to assess the accuracy of such methods, a validation study was carried out. The study focuses on two types of numerical wave tanks: 1. A numerical wave tank based a non-linear potential flow algorithm. 2. A numerical wave tank based on a Volume of Fluid algorithm. The first algorithm uses a structured grid with triangular elements and a surface tracking technique. The second algorithm uses a structured, Cartesian grid and a surface capturing technique. Validation material is available by means of waves measured at multiple locations in two different model test basins. The first method is capable of generating waves up to the break limit. Wave absorption is therefore modeled by means of a numerical beach and not by mean of the parabolic beach that is used in the model basin. The second method is capable of modeling wave breaking. Therefore, the parabolic beach in the model test basin can be modeled and has also been included. Energy dissipation therefore takes place according to physics which are more related to the situation in the model test basin. Three types of waves are generated in the model test basin and in the numerical wave tanks. All these waves are generated on basin scale. The following waves are considered: 1. A scaled 100-year North-Sea wave (Hs = 0.24 meters, Tp = 2.0 seconds) in deep water (5 meters). 2. A scaled operational wave (Hs = 0.086 meters, Tp = 1.69 seconds) at intermediate water depth (0.86 meters) generated by a flap-type wave generator. 3. A scaled operational wave (Hs = 0.046 meters, Tp = 1.2 seconds) in shallow water (0.35 meters) generated by a piston-type wave generator. The waves are generated by means of a flap or piston-type wave generator. The motions of the wave generator in the simulations (either rotational or translational) are identical to the motions in the model test basin. Furthermore, in the simulations with intermediate water depth, the non-flat contour of the basin bottom (ramp) is accurately modeled. A comparison is made between the measured and computed wave elevation at several locations in the basin. The comparison focuses on: 1. Reflection characteristics of the model test basin and the numerical wave tanks. 2. The accuracy in the prediction of steep waves. 3. Second order effects like set-down in intermediate and shallow water depth. Furthermore, a convergence study is presented to check the grid independence of the wave tank predictions.

scholarly journals Decision Support System for an Art University

2021 ◽  
Vol 1 (2) ◽  
pp. 8-12
Author(s):  
Svetlana E. Vecherskaya
Keyword(s):  
Decision Support ◽  
Decision Support System ◽  
Special Needs ◽  
Support System ◽  
Learning Process ◽  
Performance Indicators ◽  
Educational Process ◽  
Learning Plan ◽  
Specific Performance ◽  
Talented Students

A prototype of an automated decision support system for creative universities has been developed, which will allow assessing the achievements particularly talented students and identifying the needs in the learning process in order to help organize the educational process in accordance with identified capabilities. Use of a decision support system based on the Bayesian classifier is suggested which will allow to evaluate factors contributing to the progress in teaching students particular techniques, and in perspective to assess the possible resources that will be required to make changes to the learning. The list of specific performance indicators is given. The system should contribute to the formation of the learning plan, taking into account the capabilities of both a group art workshop as a whole, and special needs of an individual to develop, if necessary an individual approach.

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