Basic Principles of Hose Design

1969 ◽  
Vol 42 (3) ◽  
pp. 666-674 ◽  
Author(s):  
W. I. Harkleroad
Keyword(s):  
Fluid Pressure ◽  
Length Change ◽  
Design Principles ◽  
Basic Principles ◽  
Design Concepts ◽  
Outer Cover ◽  
Control Forces ◽  
Reinforcement Angle ◽  
Internal Pressures ◽  
And Control

Abstract Fundamentals of hose design have not changed with the introduction of new and improved component materials. Hose consists of three basic elements which are tube, reinforcement, and outer cover—with each serving a primary function. The tube or inner liner contains and resists the fluid conveyed and transmits forces created by the internal pressures to the strength member. The reinforcement or strength member contains the forces created by the fluid pressure. The outer cover protects hose reinforcement and resists external environment and damage. This paper is primarily concerned with the design concepts of the strength member or reinforcement as a functional component to resist and control forces created in service. Design principles relating to reinforcement angle, burst strength, and length change under pressure are presented for various hose styles. Braided, spiral, wrapped, loomed, wrapped ply and knitted hose styles are reviewed and compared. Reinforcement materials, their types, relative strengths and advantages are summarized. Examples of specific applications of hose are presented to illustrate hose design principles in action in industry.

scholarly journals TRANSFORMATION OF THE SYSTEM OF UNIFIED LEADERSHIP OF THE DEFENSE AND MILITARY COMMAND IN THE ARMED FORCES OF UKRAINE

2020 ◽  
pp. 697-707
Author(s):  
V. Savechko ◽  
O. Chernysh
Keyword(s):  
Armed Forces ◽  
Schematic Diagram ◽  
General Staff ◽  
Basic Principles ◽  
Military Forces ◽  
Military Command ◽  
Principles And Standards ◽  
Military Control ◽  
Control Forces ◽  
And Control

The article deals with the directions of the transformation of the joint leadership of the defense and military command and control forces in the Armed Forces of Ukraine in accordance with the Basic Principles of the organization of the joint leadership of the defense and military command in accordance with the Schematic diagram of the perspective system of the joint command of the defense and military control in the Armed Forces of Ukraine on the basis of NATO principles and standards. Attention is focused on the principles of organizing joint leadership of the defense and military forces in the Armed Forces of Ukraine. The content and essence of the principles of organizing joint leadership of the defense and military forces in the Armed Forces of Ukraine are described. The scheme of the system of combined leadership of the defense and military forces in the Armed Forces of Ukraine is given. The main functions between the structural divisions of the General Staff of the Armed Forces of Ukraine are described in detail.

On Biomineralization

1989 ◽  
Author(s):  
Heinz A. Lowenstam ◽  
Stephen Weiner
Keyword(s):  
Medical Research ◽  
Design Principles ◽  
Mineral Formation ◽  
Medical Problems ◽  
Basic Principles ◽  
Mineralized Tissues ◽  
Mineralization Processes ◽  
Archaeological Artifacts

Focusing on the basic principles of mineral formation by organisms, this comprehensive volume explores questions that relate to a wide variety of fields, from biology and biochemistry, to paleontology, geology, and medical research. Preserved fossils are used to date geological deposits and archaeological artifacts. Materials scientists investigate mineralized tissues to determine the design principles used by organisms to form strong materials. Many medical problems are also associated with normal and pathological mineralization. Lowenstam, the pioneer researcher in biomineralization, and Weiner discuss the basic principles of mineral formation by organisms and compare various mineralization processes. Reference tables listing all known cases in which organisms form minerals are included.

scholarly journals Spatiotemporal behavior of a large-scale landslide at Mt. Onnebetsu-dake, Japan, detected by three L-band SAR satellites

2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Youichiro Takada ◽  
George Motono
Keyword(s):  
Large Scale ◽  
Fluid Pressure ◽  
Surface Displacement ◽  
Length Change ◽  
Vertical Displacement ◽  
Phase Changes ◽  
Annual Rainfall ◽  
Spatiotemporal Behavior ◽  
Spatially Periodic ◽  
L Band

Abstract We applied differential InSAR analysis to the Shiretoko Peninsula, northeastern Hokkaido, Japan. All the interferograms of long temporal baseline (~ 3 years) processed from SAR data of three L-band satellites (JERS-1, ALOS, ALOS-2) commonly indicate remarkable phase changes due to the landslide movement at the southeastern flank of Mt. Onnebetsu-dake, a Quaternary stratovolcano. The area of interferometric phase change matches to known landslide morphologies. Judging from the timing of the SAR image acquisitions, this landslide has been moving at least from 1993 to the present. Successive interferograms of 1-year temporal baseline indicate the temporal fluctuation of the landslide velocity. Especially for the descending interferograms, the positive line-of-sight (LOS) length change, which indicates large subsidence relative to the horizontal movement, is observed in the upslope section of the landslide during 1993–1998, while the negative LOS change is observed in the middle and the downslope section after 2007 indicating less subsidence. The landslide activity culminates from 2014 to 2017: the eastward and the vertical displacement rates reach ~ 6 and ~ 2 cm/yr, respectively. Utilizing high spatial resolution of ALOS and ALOS-2 data, we investigated velocity distribution inside the landslide. During 2007–2010, the eastward component of surface displacement increases toward the east, implying that the landslide extends toward the east. During 2014–2017, the vertical displacement profile exhibits spatially periodic uplift and subsidence consistent with surface gradient, which indicates the ongoing deformation driven by gravitational force. Heavy rainfall associated with three typhoons in August 2016 might have brought about an increase in the landslide velocity, possibly due to elevated pore-fluid pressure within and/or at the base of the landslide material. Also, annual rainfall would be an important factor that prescribes the landslide velocity averaged over 3 years.

scholarly journals Closed-form time derivatives of the equations of motion of rigid body systems

2021 ◽  
Author(s):  
Andreas Müller ◽  
Shivesh Kumar
Keyword(s):  
Rigid Body ◽  
Closed Form ◽  
Multibody Systems ◽  
Equations Of Motion ◽  
Alternative Formulation ◽  
Dynamics Of Rigid Body ◽  
Control Forces ◽  
And Control ◽  
Derivatives Of ◽  
Insight Into

AbstractDerivatives of equations of motion (EOM) describing the dynamics of rigid body systems are becoming increasingly relevant for the robotics community and find many applications in design and control of robotic systems. Controlling robots, and multibody systems comprising elastic components in particular, not only requires smooth trajectories but also the time derivatives of the control forces/torques, hence of the EOM. This paper presents the time derivatives of the EOM in closed form up to second-order as an alternative formulation to the existing recursive algorithms for this purpose, which provides a direct insight into the structure of the derivatives. The Lie group formulation for rigid body systems is used giving rise to very compact and easily parameterized equations.

Modeling, Actuation, and Control of an Active Fluid Vibration Isolator

1997 ◽  
Vol 119 (1) ◽  
pp. 52-59 ◽  
Author(s):  
M. J. Panza ◽  
D. P. McGuire ◽  
P. J. Jones
Keyword(s):  
Electrical Power ◽  
Fluid Pressure ◽  
Space Representation ◽  
Vibration Isolator ◽  
Mass System ◽  
Integral Control ◽  
Active Fluid ◽  
State Space Representation ◽  
In Series ◽  
And Control

An integrated mathematical model for the dynamics, actuation, and control of an active fluid/elastomeric tuned vibration isolator in a two mass system is presented. The derivation is based on the application of physical principles for mechanics, fluid continuity, and electromagnetic circuits. Improvement of the passive isolator performance is obtained with a feedback scheme consisting of a frequency shaped notch compensator in series with integral control of output acceleration and combined with proportional control of the fluid pressure in the isolator. The control is applied via an electromagnetic actuator for excitation of the fluid in the track connecting the two pressure chambers of the isolator. Closed loop system equations are transformed to a nondimensional state space representation and a key dimensionless parameter for isolator-actuator interaction is defined. A numerical example is presented to show the effect of actuator parameter selection on system damping, the performance improvement of the active over the passive isolator, the robustness of the control scheme to parameter variation, and the electrical power requirements for the actuator.

FISCAL EQUIVALENCE: PRINCIPLE AND PREDATION IN THE PUBLIC ADMINISTRATION OF JUSTICE

2021 ◽  
Vol 38 (1) ◽  
pp. 244-265
Author(s):  
Emily C. Skarbek
Keyword(s):  
Public Administration ◽  
Equivalence Principle ◽  
Justice System ◽  
Service Providers ◽  
The Political ◽  
The Public ◽  
Local Police ◽  
Administration Of Justice ◽  
Internal Pressures ◽  
And Control

AbstractFiscal equivalence in the public administration of justice requires local police and courts to be financed exclusively by the populations that benefit from their services. Within a polycentric framework, broad based taxation to achieve fiscal equivalence is a desirable principle of public finance because it conceptually allows for the provision of justice to be determined by constituent’s preferences, and increases the political accountability of service providers to constituents. However, the overproduction of justice services can readily occur when the benefits of the justice system are not enjoyed equally. Paradoxically, the same properties that make fiscal equivalence desirable by imposing restraint and control between constituents and local government also create internal pressures for agents of the state to engage in predatory, revenue-generating behavior.

scholarly journals A Review on Generation and Mitigation of Airfoil Self-Induced Noise

2021 ◽  
Vol 90 (1) ◽  
pp. 163-178
Author(s):  
Mohamed Ibren ◽  
Amelda Dianne Andan ◽  
Waqar Asrar ◽  
Erwin Sulaeman
Keyword(s):  
Parametric Design ◽  
Acoustic Scattering ◽  
Feedback Mechanism ◽  
Flow Topology ◽  
Trailing Edge ◽  
Airfoil Surface ◽  
Design Concepts ◽  
Acoustic Control ◽  
Passive Acoustic ◽  
And Control

A review on passive acoustic control of airfoil self-noise by means of porous trailing edge is presented. Porous surfaces are defined using various terms such as porosity, permeability, resistivity, porosity constant, dimensionless permeability, flow control severity and tortuosity. The primary purpose of this review paper is to provide key findings regarding the sources and mitigation techniques of self-induced noise generated by airfoils. In addition, various parametric design concepts were presented, which are critically important for porous-airfoil design specifications. Most research focus on experimentation with some recent efforts on numerical simulations. Detail study on flow topology is required to fully understand the unsteady flow nature. In general, noise on the airfoil surface is linked to the vortex shedding, instabilities on the surface, as well as feedback mechanism. In addition, acoustic scattering can be minimized by reducing extent of the porous region from the trailing edge while increasing resistivity. Moreover, blowing might also be another means of reducing noise near the trailing edge. Ultimately, understanding the flow physics well provides a way to unveil the unknowns in self-induced airfoil noise generation, mitigation, and control.

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