The Distribution of Temperatures in a Hot/Cold Die Set: The Effect of the Pressure, Temperature, and Material

1995 ◽  
Vol 117 (2) ◽  
pp. 220-227 ◽  
Author(s):  
J. G. Lenard ◽  
M. E. Davies
Keyword(s):  
Initial Conditions ◽  
Control Program ◽  
The Body ◽  
Temperature Fields ◽  
Surface Temperatures ◽  
Direct Measurements ◽  
Die Set ◽  
The Difference ◽  
Interface Pressures

Modern hot metalforming operations require a predictive-adaptive control program in which the predictive component precalculates the necessary parameters—such as temperatures and loads—and the adaptive component sets up, monitors and adjusts the forming equipment. One of the needs of a predictive model of the process is for an understanding of the boundary conditions at the surface of contact. For high temperature operations, one of these conditions is described by the heat transfer coefficient, relating the heat flux and the difference of the temperatures of the contacting surfaces, at the die-workpiece interface. The surface temperatures are, of course, dependent on the distribution of the temperatures within the body of the dies. The determination of these distributions is the topic of the present project. Thermocouples embedded in a cold/hot die set as well as thermocouples placed on the surface of contact are used to monitor the temperature fields, within the body as well as on the surfaces, for various interface pressures, initial temperatures and materials. The results indicate that direct measurements of the temperatures of the contacting surfaces is very difficult and may lead to significant errors. It is recommended that a mathematical model, which uses the measured internal temperatures as initial conditions, should be employed to calculate the contact surface temperatures.

scholarly journals Analysis of an intense bora event in the Adriatic area

2004 ◽  
Vol 4 (2) ◽  
pp. 323-337 ◽  
Author(s):  
D. Cesini ◽  
S. Morelli ◽  
F. Parmiggiani
Keyword(s):  
Satellite Data ◽  
Initial Conditions ◽  
Atmospheric Model ◽  
Horizontal Resolution ◽  
Sea Surface ◽  
Temperature Fields ◽  
Sea Surface Temperatures ◽  
Low Level ◽  
Surface Temperatures ◽  
The Difference

Abstract. Numerical simulations of a bora event, recently occurred in the Adriatic area, are presented. Two reference runs at different horizontal resolution (about 20km and 8km) describe the case. Initial conditions for the atmospheric model integration are obtained from ECMWF analyses. Satellite data are used for comparisons. A further run at horizontal resolution of 8km, using initial satellite sea surface temperatures, is performed to evaluate their impact on the low level wind over the Adriatic Sea. All the simulations are carried out with 50 layers in the vertical. Numerous aspects of the simulations are found to be in agreement with the understanding as well as the observational knowledge of bora distinctive characteristics. Satellite data and model results indicate that a more realistic simulation of the bora wind over the sea is achieved using the model with 8km horizontal resolution and that the low level wind in this case is sensitive, though weakly, to the difference between the used sea surface temperature fields. Simulation results also show that both wind intensity and the area around wind peaks tend to increase when relatively higher sea surface temperatures are used.

XXI. Description of a hydropneumatic baroscope

1839 ◽  
Vol 129 ◽  
pp. 425-431
Keyword(s):  
Thin Sheet ◽  
Simple Calculation ◽  
The Body ◽  
The Other ◽  
Floating Body ◽  
Convex Side ◽  
The Difference ◽  
Increased Pressure ◽  
Brass Wire

The principle on which the instrument I am about to describe is constructed, is, that the volume of a given quantity of air under a constant temperature, is inversely as the pressure to which it is subjected ; and the means I employ to estimate the change of volume which that quantity of air undergoes, by being subjected to differences of pressure caused by a change of elevation, are the determination of the difference of weight which a floating body is capable of sustaining in both situations. Thus, if a vessel containing a quantity of air and water be floated in water, and there be a com­munication between the water in the floating body and that in which it floats, it will follow, that when such an apparatus is subjected to diminished pressure, the air within the float will dilate, and cause a volume of water equal in amount to the dilatation of the air to be driven from the float; and the difference of weight which the floating body will sustain, will be the exact weight of the water expelled : if such an appa­ratus is subjected to an increased pressure, the air within it will contract, and consequently a quantity of water, from that in which it floats, will enter the float, and the diminished weight it is capable of sustaining will be the weight of the water which has entered the float, in consequence of the diminution of the volume of the air. It is by such means, with the instrument immediately to be described, and by the help of a very simple calculation, that I propose to determine the difference of level between any two places. Plate X. fig. 1. represents the floating part, made of thin sheet brass, the body of which ( a ), in form the frustum of a cone, is nine inches long, two inches in dia­meter at one end, and one inch at the other, and capable of containing about fourteen cubic inches. In the centre of the widest end, a small stud of brass ( b ) is hard sol­dered, into which a brass wire ( c ) is screwed, an inch and three-eighths long, and about one twenty-fifth or one thirtieth of an inch in diameter : the other end of the wire is screwed into a brass stud in the middle of the convex side of a shallow cup ( d ), made also of brass, and as light as possible, so that it will retain its shape, and be capable of sustaining a weight of about eight hundred or one thousand grains.

scholarly journals HEMATOSALIVAL BARRIER IN CLINICAL PRACTICE

2021 ◽  
Vol 17 (2) ◽  
pp. 62-67
Author(s):  
Oleg Chuykin ◽  
Maria Shtanko ◽  
Kristina Kuchuk
Keyword(s):  
Oral Fluid ◽  
Biological Fluids ◽  
The Body ◽  
Internal Environment ◽  
Pathological Conditions ◽  
Therapeutic Measures ◽  
The Difference ◽  
And Control ◽  
Level Analysis

To maintain homeostasis of the internal environment of the body, mechanisms are needed that control the exchange of various components between blood and the internal environment of tissues and organs. One of these physiological structures is the blood-salivary barrier, which regulates the selective metabolism between blood and oral fluid. Changes in the composition of biological fluids (blood and saliva) can be used as markers for diagnosing pathological conditions of the body and the dynamics of therapeutic measures. Of great importance is the study of the blood-salivary barrier for the search for drugs that are selectively transferred from the blood to the saliva. Some drugs are excreted in saliva at a concentration higher than they are in the blood. However, more often the concentration of drugs in saliva is much lower than in blood serum. Purpose: to form a list of the main trends and scientific and practical directions on the func-tioning of the hematosalvarial barrier. Materials and methods: to analyze the topic of the clinical significance of the hematosalvarial barrier, periodicals and scientific journals of domestic and foreign literature were studied, which determined the difference in the levels of trace elements, hormones, immune complexes between the oral fluid and serum. Conclusion: Analysis of literature data shows that the function of the blood-salivary barrier acts as a nonspecific adaptive mechanism, while saliva reflects the state of the protective functions of the barrier at the organismal level. Analysis of the selectivity and permeability of the blood-salivary barrier, as well as determination of changes in the composition and proper-ties of blood and oral fluid, can optimize and facilitate the diagnosis and control of treatment of various diseases of the oral cavity and the body as a whole.

Fidelity of the Estimation of the Deformation Gradient From Data Deduced From the Motion of Markers Placed on a Body That is Subject to an Inhomogeneous Deformation Field

2013 ◽  
Vol 135 (8) ◽  
Author(s):  
Vít Průša ◽  
K. R. Rajagopal ◽  
U. Saravanan
Keyword(s):  
Finite Number ◽  
Data Reduction ◽  
Deformation Gradient ◽  
Quantitative Description ◽  
The Body ◽  
Inhomogeneous Deformation ◽  
Actual Error ◽  
The Difference

Practically all experimental measurements related to the response of nonlinear bodies that are made within a purely mechanical context are concerned with inhomogeneous deformations, though, in many experiments, much effort is taken to engender homogeneous deformation fields. However, in experiments that are carried out in vivo, one cannot control the nature of the deformation. The quantity of interest is the deformation gradient and/or its invariants. The deformation gradient is estimated by tracking positions of a finite number of markers placed in the body. Any experimental data-reduction procedure based on tracking a finite number of markers will, for a general inhomogeneous deformation, introduce an error in the determination of the deformation gradient, even in the idealized case, when the positions of the markers are measured with no error. In our study, we are interested in a quantitative description of the difference between the true gradient and its estimate obtained by tracking the markers, that is, in the quantitative description of the induced error due to the data reduction. We derive a rigorous upper bound on the error, and we discuss what factors influence the error bound and the actual error itself. Finally, we illustrate the results by studying a practically interesting model problem. We show that different choices of the tracked markers can lead to substantially different estimates of the deformation gradient and its invariants. It is alarming that even qualitative features of the material under consideration, such as the incompressibility of the body, can be evaluated differently with different choices of the tracked markers. We also demonstrate that the derived error estimate can be used as a tool for choosing the appropriate marker set that leads to the deformation gradient estimate with the least guaranteed error.

scholarly journals Calibration of a dynamic Eulerian-lagrangian model for the computation of wood cylinders transport in shallow water flow

2018 ◽  
Vol 21 (1) ◽  
pp. 164-179 ◽  
Author(s):  
Elisabetta Persi ◽  
Gabriella Petaccia ◽  
Stefano Sibilla ◽  
Pilar Brufau ◽  
Pilar García-Navarro
Keyword(s):  
Initial Conditions ◽  
Fluid Flows ◽  
Rigid Bodies ◽  
The Body ◽  
Lagrangian Model ◽  
Preliminary Evaluation ◽  
Floating Bodies ◽  
Inertia Coefficient ◽  
Planar Rotation ◽  
The Difference

Abstract A computational Eulerian–Lagrangian model (ORSA2D_WT) is used for modelling the movement of floating rigid bodies on the water surface. The two-dimensional transport is computed with a dynamic approach, modifying existing formulations for the transport of bodies within fluid flows for the case of floating bodies, by adopting suitable added mass, drag and side coefficients. An original formulation for planar rotation is proposed, which includes the effect of the hydrodynamic torque and a resistance term, named added inertia, based on the difference between the angular velocity of the flow and that of the body. The value of the added inertia coefficient is calibrated against experiments made on purpose, involving the transport of a cylinder in a flume with two side obstacles. The calibrated code is applied to a slightly larger set of experiments for its preliminary evaluation. The outcome of the simulations shows that the streamwise and transversal displacements are well modelled, while some inaccuracies arise when considering the cylinder orientation. The effects of the initial conditions on the cylinders' trajectory and rotation are discussed, showing their influence on the evolution of the rotation angles.

Problems of theStufenbaulehre: Kelsen’s Failure to Derive the Validity of a Norm from Another Norm

2007 ◽  
Vol 20 (1) ◽  
pp. 35-67 ◽  
Author(s):  
András Jakab
Keyword(s):  
Legal Order ◽  
The Body ◽  
Dead Body ◽  
Basic Norm ◽  
The Difference ◽  
Theory Of Law ◽  
Transplanted Organs ◽  
Logical Result ◽  
Law Making

TheStufenbaulehreis a central and founding element of the Pure Theory of Law (PTL).Most of the criticism ofStufenbaulehretargets the idea of the basic norm (Grundnorm), however unjustified. This criticism stems from a misunderstanding of the presumptive character of the basic norm and of the whole legal order. Others have criticised the relativisation of the difference between individual and general norms, Kelsen’s monism, and the determination of the validity of a norm by a single other norm. This can be refuted as well - either because their critique does not concern an essential part ofStufenbaulehre(monism), or becauseStufenbaulehrecan be saved by making a small modification to it. However, there is one lethal criticism. It concerns the founding thought of the wholeStufenbaulehre, i.e., the derivation of validity. In a law-making process, there is never a derivation of validity: the logical result of a law-making process is only a norm saying “The new norm ought to be valid.” Whether the new norm is in fact valid, is a different issue which is not dealt with by the PTL. This has serious consequences: Without this derivationStufenbaulehrecannot survive, and withoutStufenbaulehre, PTL cannot survive either. Some valuable parts of PTL might be used in other legal theories, but these are nothing but transplanted organs from the dead body of PTL whose heart-Stufenbaulehre-can no longer keep the body alive.

scholarly journals Laboratory investigation on hydraulic anisotropy behavior of unsaturated soil

2017 ◽  
Vol 54 (7) ◽  
pp. 1034-1046 ◽  
Author(s):  
Priono ◽  
Harianto Rahardjo ◽  
Kalyani Chatterjea ◽  
Eng-Choon Leong
Keyword(s):  
Direct Measurement ◽  
Unsaturated Soil ◽  
Initial Conditions ◽  
Characteristic Curve ◽  
Transient Time ◽  
Indirect Determination ◽  
Direct Measurements ◽  
Hydraulic Anisotropy ◽  
Unsaturated Condition

Hydraulic anisotropy behavior of unsaturated soil has not been fully investigated. Direct laboratory measurement and indirect determination of hydraulic anisotropy under a drying condition were carried out on statically compacted specimens having different initial conditions. Direct measurement of permeability was carried out using an unsaturated triaxial permeameter whereas indirect determination of permeability was performed through statistical estimation via a measured drying soil–water characteristic curve (SWCC). In this research, two orientations — specifically horizontal-layering (HL) and vertical-layering (VL) orientations — were prepared for a given specimen from statically compacted homogeneous sand–kaolin. The results from both direct measurement and indirect determination of hydraulic anisotropy were in good agreement. Hydraulic anisotropy under an unsaturated condition was found to be similar with that in a saturated condition. Moreover, hydraulic anisotropy was reflected in the ratio of transient time during the direct measurements of HL and VL specimens at high matric suctions. In contrast, in the indirect method, hydraulic anisotropy was reflected in the ratio of equalization time during SWCC tests at matric suctions higher than the air-entry value of the soil.

scholarly journals Numerical and experimental determination of in-structure temperature profiles

2015 ◽  
Vol 10 (1) ◽  
pp. 65-72 ◽  
Author(s):  
Marek Zozulák ◽  
Dušan Katunský
Keyword(s):  
Temperature Field ◽  
Initial Conditions ◽  
Building Envelope ◽  
The Body ◽  
Temperature Profiles ◽  
Initial Condition ◽  
Start Up ◽  
Outdoor Test ◽  
Building Physics

Abstract When building physics simulations are done initial conditions express the actual hygrothermal state of building envelope. For the temperature field simulations initial condition is represented by the initial temperature in the body profile at the start of heat transfer. In-structure temperature varies quickly so temperature initial conditions are often neglected. Nevertheless in specific cases initial conditions have to be taken into an account even when simple temperature field simulations are done. The contribution shows various temperature initial conditions determination for insulated construction of outdoor test cell. Comparison of measured and calculated temperature profiles in structure shows correctness of start-up pre-calculation initial condition consideration

Regulation of Plasma Creatinine Concentration by Use of a Servo Control System

1968 ◽  
Vol 14 (10) ◽  
pp. 944-959 ◽  
Author(s):  
Rodney B Harvey ◽  
James B Bassingthwaighte ◽  
Richard L Heppner
Keyword(s):  
Infusion Pump ◽  
The Body ◽  
Servo Control ◽  
Plasma Creatinine ◽  
Creatinine Concentration ◽  
Servo Control System ◽  
Plasma Creatinine Concentration ◽  
The Difference ◽  
Continuous Determination

Abstract A method for controlling the plasma creatinine concentration is described. This method uses continuous determination of the plasma creatinine concentration and a servomechanism which drives an infusion pump at a rate proportional to the difference between the actual and desired creatinine concentrations. The rate and volume of creatinine infusion necessary to maintain the desired plasma concentration provide information related to kidney function and the accumulation of creatinine in the body. Experiments using this technic and the method of data analysis are described. It has been shown that under certain conditions this technic may be used to estimate the renal clearance of creatinine and the size and nature of the space into which creatinine is distributed in the dog.

Low Frequency Radar (LFR) on the JUVENTAS CubeSat for HERA / ESA mission

2020 ◽  
Author(s):  
Alain Herique ◽  
Dirk Plettemeier ◽  
Wlodek Kofman ◽  
Yves Rogez ◽  
Hannah Goldberg
Keyword(s):  
Internal Structure ◽  
Low Frequency ◽  
The Body ◽  
Binary Asteroid ◽  
Direct Observations ◽  
Direct Measurements ◽  
Secondary Objective ◽  
Small Platform

<p>The Low Frequency Radar (LFR) on the JUVENTAS CubeSat for HERA / ESA mission to Didymos Binary Asteroid is a unique opportunity to perform direct measurements of its internal structure and regolith. LFR has been developed to fathom asteroid from a small platform. This instrument is inherited from CONSERT/Rosetta and has been redesigned in the frame of the AIDA and HERA ESA mission.</p><p>Onboard JUVENTAS, LFR is operating in monostatic mode to probe down to the first hundreds of meters into the subsurface and to achieve a full tomography of the Didymos' moonlet. Direct observations of the internal structure of asteroids can solve still open basic questions like: Is the body a monolithic piece of rock or a rubble-pile? How high is the porosity? What is the typical size of the constituent blocks? Are these blocks homogeneous or heterogeneous? How is the regolith covering its surface constituted?</p><p>The low frequency aboard the Juventas CubeSat will contribute to the solution of these open and for planetary defense crucial questions.<br>- The first LRF objective is the characterization of the moonlet interior, to identify internal structure and to analyze the size distribution and heterogeneity of constitutive blocks from sub metric to global<br>- The second objective is the estimation of average permittivity and mapping of its spatial variation especially in the crater area.<br>- The same characterization applied to the main of the binary system is among secondary objectives.<br>- Supporting shape modeling and determination of the dynamical state by radar ranging is a further secondary objective.</p><p>This paper will present the instrument concept and measurement strategy, its performances and the expected science return.</p>

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