scholarly journals A UNIQUE INSTRUMENTATION SCHEME FOR MEASURING LOADS IN MODEL DOLOS UNITS

1986 ◽  
Vol 1 (20) ◽  
pp. 163 ◽  
Author(s):  
R.D. Scott ◽  
D.J. Turcke ◽  
W.F. Baird
Keyword(s):  
Structural Integrity ◽  
Design Procedure ◽  
Structural Response ◽  
Load Cell ◽  
Physical Models ◽  
Unit Load ◽  
Overall Design ◽  
The Individual ◽  
Static Point ◽  
Hydraulic Stability

An instrumentation scheme for the measurement of the structural response of dolos units in a physical model due to static and quasistatic forces is presented. This was achieved by the development of a specialized armour unit "load cell". The load cell was tested under a variety of loading conditions ranging from static point loads to the complex forces arising from simulated prototype wave action. In the final stage of testing, a model breakwater was constructed and analyzed. The results of these tests demonstrated the accuracy of the developed instrumentation and the feasibility of its use for measurements conducted in physical models. Knowledge of the structural response of armour units in the breakwater environment may be incorporated into an improved overall design procedure for armour units that considers both the hydraulic stability and the structural integrity of the individual units.

scholarly journals ARMOUR UNIT STRUCTURAL RESPONSE - A PARAMETRIC STUDY

1988 ◽  
Vol 1 (21) ◽  
pp. 176
Author(s):  
C. David Anglin ◽  
William F. Baird ◽  
Etienne P.D. Mansard ◽  
R. Douglas Scott ◽  
David J. Turcke
Keyword(s):  
Wave Height ◽  
Parametric Study ◽  
Structural Integrity ◽  
Design Procedure ◽  
Structural Response ◽  
Design Parameters ◽  
Coastal Structures ◽  
Log Normal ◽  
Wave Induced ◽  
Hydraulic Stability

There is a general lack of knowledge regarding the nature and magnitude of loads acting on armour units used for the protection of rubblemound coastal structures. Thus, a comprehensive design procedure incorporating both the hydraulic stability and the structural integrity of the armour units does not exist. This paper presents the results of a detailed parametric study of the structural response of armour units to wave-induced loading in a physical breakwater model. The effect of the following design parameters is investigated: breakwater slope, armour unit location, wave period and wave height. This research has made a number of significant contributions towards the development of a comprehensive design procedure for concrete armour units. It has identified a linear relationship between the wave-induced stress in the armour units and the incident wave height. In addition, it has shown that the conditional probability of waveinduced stress given wave height can be estimated by a log-normal distribution. Finally, a preliminary design chart has been developed which incorporates both the structural integrity and the hydraulic stability of the armour units.

scholarly journals STRUCTURAL DESIGN PROCEDURES FOR CONCRETE ARMOUR UNITS

1984 ◽  
Vol 1 (19) ◽  
pp. 172 ◽  
Author(s):  
Kevin R. Hall ◽  
W.F. Baird ◽  
D.J. Turcke
Keyword(s):  
Structural Design ◽  
Rational Design ◽  
Structural Integrity ◽  
Design Procedure ◽  
Analytical Techniques ◽  
Structural Performance ◽  
Design Procedures ◽  
Design Loads ◽  
Resultant Stress ◽  
Hydraulic Stability

A rational design procedure for rubblemound breakwater protection which will ensure both the structural integrity and hydraulic stability of individual concrete armour units and the overall armour system is presented. The procedure involves new experimental techniques for measuring strains in model concrete armour units in a hydraulic model of a breakwater subjected to simulated prototype wave attack and analytical techniques for determining equivalent prototype loads on units. Selected design loads are used to define the resultant stress distribution to allow the designer to take the necessary measures to ensure the structural performance of the unit in a breakwater environment•

scholarly journals A PROCEDURE FOR THE ANALYSIS AMD DESIGN OF CONCRETE ARMOR UNITS

1986 ◽  
Vol 1 (20) ◽  
pp. 127
Author(s):  
W.F. Baird ◽  
J.S. Readshaw ◽  
R.D. Scott ◽  
D.J. Turcke
Keyword(s):  
Interaction Design ◽  
Structural Integrity ◽  
Design Procedure ◽  
Rational Approach ◽  
Design Alternatives ◽  
Interaction Curves ◽  
Improved Design ◽  
The Cost ◽  
Rubble Mound Breakwaters ◽  
Hydraulic Stability

A rational approach to the design of rubble mound breakwaters that incorporates both the hydraulic stability and the structural integrity of individual concrete armor units is presented. A key element of this improved design procedure is the development of instrumentation to measure loads occurring on armor units in a physical model of a breakwater. Numerical methods have been employed to determine stresses throughout the armor unit once the loads are known and interaction design curves were developed from measured data. These interaction curves provide a useful assessment of the structural integrity of the armor units. The curves clearly demonstrate the overall factor of safety associated with the armor unit and the expected mode of failure. Based on the results of this type of analysis, the cost effectiveness and safety associated with different design alternatives may be explored and a breakwater that is both hydraulically and structurally efficient may be designed.

Public Facilities Design in Sustainable Ways for Reconstruction Work of Yushu Area

2014 ◽  
Vol 672-674 ◽  
pp. 2195-2210
Author(s):  
Ang Li ◽  
Shu Bin Kan ◽  
Xin Zhang ◽  
Xin Yu Song ◽  
Shi Long Zhang
Keyword(s):  
Design Theory ◽  
Physical Models ◽  
Overall Design ◽  
Public Facilities ◽  
Local Characteristics ◽  
Current State ◽  
Environmental Friendly ◽  
The World ◽  
Facilities Design ◽  
Pros And Cons

The region of Yushu has fragile natural environment. In 2010, it suffered severe damages caused by earthquakes. This paper subject, on the basis of status research of natural and cultural environment in Yushu area and urban public facilities across the world, is aiming at a design attempt of public facilities suitable for Yushu area under the guidance of sustainable-development design theory. After constructing computer models, we made physical models to further test the reliability of our scheme. The overall design acts according to circumstances, and makes it environmental friendly, developmental sustainable, economical, aesthetic, practical and reliable. We also added to our design some local characteristics to make it better integrate into the local natural environmental features so that it could be widely used. In the end, we summarized the pros and cons of the scheme through theoretical analysis of our design process, despite that, in June 2014, we had an on-the-spot investigation in Yushu, and according to its current state of development, we made outlooks of our further scheme practice.

scholarly journals When Resources Are Scarce - Feasibility of Emergency Ventilation of Two Patients With One Ventilator

2020 ◽  
Author(s):  
Peter C. Reinacher ◽  
Thomas E. Schlaepfer ◽  
Martin A. Schick ◽  
Jürgen Beck ◽  
Hartmut Bürkle ◽  
...  
Keyword(s):  
Tidal Volume ◽  
Respiratory System ◽  
Breathing Circuit ◽  
Absolute Error ◽  
Physical Models ◽  
Respiratory System Mechanics ◽  
Emergency Ventilation ◽  
Artificial Lungs ◽  
Circuit Components ◽  
The Individual

AbstractA potential shortage of intensive care ventilators has led to the idea to ventilate more than one patient with a single ventilator. Besides other problems, this is associated with the lack of knowledge concerning distribution of tidal volume and the patients’ individual respiratory system mechanics.In this study we used two simple hand-manufactured adaptors to connect physical models of two adult respiratory systems to one ventilator. The artificial lungs were ventilated in the pressure-controlled mode and we investigated if disconnecting one lung from the ventilation circuit for several breaths would allow to determine reliably the other lung’s tidal volume and compliance.Compliances and volumes were measured both with the ventilator and external sensors corresponded well. However, tidal volumes measured via the ventilator were smaller compared to the tidal volumes measured via the external sensors with an absolute error of 5.3 ± 2.5%. The tidal volumes of the individual artificial lungs were distributed in proportion to the compliances and did not differ relevantly when both artificial lungs were connected to when one was disconnected.We conclude that in case of emergency, ventilation of two patients with one ventilator requires two simple hand-crafted tubes as adaptors and available standard breathing circuit components. In such a setting, respiratory system mechanics and tidal volume of each individual patient can be reliably measured during short term clamping of the tracheal tube of the respective other patient.

New evidence for the life habit of graptoloids from physical modelling

Paleobiology ◽  
1989 ◽  
Vol 15 (4) ◽  
pp. 402-413 ◽  
Author(s):  
Susan Rigby ◽  
Barrie Rickards
Keyword(s):  
Narrow Band ◽  
Physical Modelling ◽  
Physical Models ◽  
Life Habit ◽  
Passive Rotation ◽  
Directional Motion ◽  
Mode Of Life ◽  
The Individual ◽  
New Evidence ◽  
Colony Shape

Physical models of graptolites have been constructed for a range of morphologies, with emphasis on planar, multiramous forms. The models are life size and have the density of a living graptolite, based on the now-established collagenous nature of the periderm and unavoidable assumptions about the amount of extrathecal tissue present in the living colony. These models have been used to test the two main hypotheses of graptolite life habit developed by Bulman, Rickards, Kirk, and others. Testing of graptoloid models in water suggests that many rhabdosome shapes were designed for passive rotation within the water column. This is caused in the models by a variety of modifications, including changes in thecal and stipe orientation, alterations of colony shape and the addition of vanes and hooks. Rotation would only have been useful when the rhabdosome was in directional motion and the frequency of such modifications seems anomalous if no such movement occurred. Thus movement by some means is required, either passively, by changes in buoyancy, or by automobility. Spiralling action would increase the harvesting path of an individual living on a planar, multiramous colony, making this a theoretically advantageous mode of life for the morphology. It would prevent the individual zooids of scandent biserial and uniserial colonies from feeding from the same narrow band of water.

Hygrothermal Behaviour of Inorganic Binder-Based Board Materials

2021 ◽  
Vol 321 ◽  
pp. 157-164
Author(s):  
Jan Bubeník ◽  
Jiří Zach
Keyword(s):  
External Environment ◽  
Physical And Mechanical Properties ◽  
Building Structure ◽  
Internal Environment ◽  
Air Humidity ◽  
Overall Design ◽  
Short Rotation ◽  
The Individual ◽  
Hygrothermal Behaviour ◽  
Diffusion Properties

Currently, the use of board materials as a material intended for the dry construction of building structure cladding in the building industry has become widespread. The most common types of board materials include wood-based boards (particle, fibre, laminated / plywood, oriented strand boards [OSB]), cement-bonded particleboards and gypsum plasterboards or gypsum fibre boards. In the case of board materials based on inorganic binders, these are most often represented by boards in which the fillers used are bonded by plaster or cement. Wood can then be used as filler, which is predominantly an assortment of inferior-quality trees or comes from a short rotation coppice, treated by various technological processes. Microstructure and material composition have the greatest influence on the physical and mechanical properties of the boards. The use of the boards in the internal or external environment is determined by their individual properties. Another indicator for the possible use of boards is the form of moisture with which the board comes into contact after installation into the structure. For the external environment, the boards have to withstand mainly liquid moisture; in contrast, in an internal environment, the boards come into contact mainly with air humidity. The diffusion properties of the individual products are also crucial for the overall design and use of the boards for structure cladding.

Designing a Compact Wireless Network Based Device-Free Passive Localisation System for Indoor Environments

2018 ◽  
pp. 1424-1439
Author(s):  
Philip Vance ◽  
Girijesh Prasad ◽  
Jim Harkin ◽  
Kevin Curran
Keyword(s):  
Assisted Living ◽  
Ambient Assisted Living ◽  
Design Procedure ◽  
The Elderly ◽  
Healthcare Services ◽  
Indoor Environments ◽  
Signal Processing Technique ◽  
Minimum Number ◽  
The Individual ◽  
Device Free

Determining the location of individuals within indoor locations can be useful in various scenarios including security, gaming and ambient assisted living for the elderly. Healthcare services globally are seeking to allow people to stay in their familiar home environments longer due to the multitude of benefits associated with living in non-clinical environments and technologies to determine an individual's movements are key to ensuring that home emergencies are detected through lack of movement can be responded to promptly. This paper proposes a device-free localisation (DFL) system which would enable the individual to proceed with normal daily activities without the concern of having to wear a traceable device. The principle behind this is that the human body absorbs/reflects the radio signal being transmitted from a transmitter to one or more receiving stations. The proposed system design procedure facilitates the use of a minimum number of wireless nodes with the help of a principle component analysis (PCA) based intelligent signal processing technique. Results demonstrate that human detection and tracking are possible to within 1m resolution with a minimal hardware infrastructure.

scholarly journals Fish Cells, a new zero Poisson’s ratio metamaterial—Part I: Design and experiment

2020 ◽  
Vol 31 (13) ◽  
pp. 1617-1637
Author(s):  
Mohammad Naghavi Zadeh ◽  
Iman Dayyani ◽  
Mehdi Yasaee
Keyword(s):  
Numerical Analysis ◽  
Numerical Model ◽  
Poisson’S Ratio ◽  
Structural Integrity ◽  
Structural Response ◽  
Poisson's Ratio ◽  
Experimental Investigations ◽  
Fish Cells ◽  
Force Displacement ◽  
Model Approach

A novel cellular mechanical metamaterial called Fish Cells that exhibits zero Poisson’s ratio in both orthogonal in-plane directions is proposed. Homogenization study on the Fish Cells tessellation is conducted and substantially zero Poisson’s ratio behavior in a homogenized tessellation is shown by numerical analysis. Experimental investigations are performed to validate the zero Poisson’s ratio feature of the metamaterial and obtain force–displacement response of the metamaterial in elastic and plastic zone. A detailed discussion about the effect of the numerical model approach and joints on the structural response of the metamaterial is presented. Morphing skin is a potential application for Fish Cells metamaterial because of the integration benefits of zero Poisson’s ratio design. The structural integrity of the Fish Cells is investigated by studying the stiffness augmentation under tension and in presence of constraints on transverse edges. Finally, geometrical enhancements for improved integrity of the Fish Cells are presented that result in substantially zero stiffness augmentation required for morphing skins.

scholarly journals A Nonmathematical Review of Optimal Operator and Experimental Design for Uncertain Scientific Models with Application to Genomics

2019 ◽  
Vol 20 (1) ◽  
pp. 16-23
Author(s):  
Edward R. Dougherty
Keyword(s):  
Experimental Design ◽  
Regulatory Networks ◽  
Design Procedure ◽  
Control Policy ◽  
Physical Models ◽  
Scientific Models ◽  
Biomedical Science ◽  
Scientific Model ◽  
Basic Aspect ◽  
Modern Engineering

Introduction: The most basic aspect of modern engineering is the design of operators to act on physical systems in an optimal manner relative to a desired objective – for instance, designing a control policy to autonomously direct a system or designing a classifier to make decisions regarding the system. These kinds of problems appear in biomedical science, where physical models are created with the intention of using them to design tools for diagnosis, prognosis, and therapy. Methods: In the classical paradigm, our knowledge regarding the model is certain; however, in practice, especially with complex systems, our knowledge is uncertain and operators must be designed while taking this uncertainty into account. The related concepts of intrinsically Bayesian robust operators and optimal Bayesian operators treat operator design under uncertainty. An objective-based experimental design procedure is naturally related to operator design: We would like to perform an experiment that maximally reduces our uncertainty as it pertains to our objective. Results & Discussion: This paper provides a nonmathematical review of optimal Bayesian operators directed at biomedical scientists. It considers two applications important to genomics, structural intervention in gene regulatory networks and classification. Conclusion: The salient point regarding intrinsically Bayesian operators is that uncertainty is quantified relative to the scientific model, and the prior distribution is on the parameters of this model. Optimization has direct physical (biological) meaning. This is opposed to the common method of placing prior distributions on the parameters of the operator, in which case there is a scientific gap between operator design and the phenomena.

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