Autonomous Profiling Measurement of Two Dimensional Section Forms Using Small-sized Ultrasonic Probe

Although airflow is invisible, it has a big influence on the indoor environment. An incorrectly planned HVAC systems can lead to draught and thermal discomfort in occupied zones. Since the commissioning tests required after the installation of HVAC systems are generally performed without occupancy, the tests results do not always accurately represent the airflow that occurs during ordinary usage. The airflow needs to be continuously monitored and controlled by an intelligent HVAC system. The aim of this study is to develop a new two-dimensional airflow sensor for the monitoring of indoor airflow, which can also indicate the flow direction. Several of these sensors can be placed in a planar sensor array, by which a two-dimensional section of the flow field is created. By recording data from several of these arrays simultaneously, an image of the three-dimensional flow could be acquired. The prototype of the sensor, which is made by Hahn-Schickard Society for Applied Research is currently being validated at the Institute for Building Energetics, Thermotechnology and Energy Storage. When the development is completed, it will greatly contribute to the control strategies of HVAC systems.

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Performance Analysis of Two-Dimensional Section of Partially Textured Piston Ring with Cavitation Boundary Conditions

Surface Topography Metrology and Properties ◽

10.1088/2051-672x/abfd05 ◽

2021 ◽

Author(s):

Ashok Atulkar ◽

Raj K Pandey ◽

Subbarao P.M.V.

Keyword(s):

Performance Analysis ◽

Boundary Conditions ◽

Piston Ring ◽

Two Dimensional ◽

Dimensional Section

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Uncoupled Dynamic Thermal Stress Distribution on the Section of a Flow Channel Occupied Filling Medium

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.394.185 ◽

2013 ◽

Vol 394 ◽

pp. 185-191

Author(s):

Jie Liu ◽

Xiao Ling Jia ◽

Neng Qiang Chai

Keyword(s):

Thermal Stress ◽

Stress Distribution ◽

Analytical Solution ◽

Elliptic Flow ◽

Flow Channel ◽

Two Dimensional ◽

Coordinate Axis ◽

Rotation Method ◽

Thermal Stress Distribution ◽

Dimensional Section

Throught translation and rotation method of coordinate axis, a problem of the dynamic thermal stress distribution on the two-dimensional section of a flow channel occupied filling medium was studied theoretically. A general analytical solution with related computional process was described in detailed. As an illustration sample, some numberical results are shown in the figure about the dynamical thermal stress distribution on the section of an elliptic flow channel occupied filling medium.

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Off-Axis STEM or TEM Holography Combined with Four-Dimensional Diffraction Imaging

Microscopy and Microanalysis ◽

10.1017/s1431927604040267 ◽

2004 ◽

Vol 10 (1) ◽

pp. 9-15 ◽

Cited By ~ 6

Author(s):

J.M. Cowley

Keyword(s):

Reference Beam ◽

Transmission Function ◽

Two Dimensional ◽

Data Set ◽

Ultrahigh Resolution ◽

Transmission Electron ◽

Scanning Transmission ◽

Diffraction Imaging ◽

Resolution Imaging ◽

Dimensional Section

Ultrahigh-resolution imaging may be achieved using modifications of the off-axis holography scheme in a scanning transmission electron microscopy (STEM) instrument equipped with one or more electrostatic biprisms in the illuminating system. The resolution is governed by the diameter of a reference beam, reduced by channeling through a line of atoms in an atomic-focuser crystal. Alternatively, the off-axis holography may be combined with the Rodenburg method in which a four-dimensional data set is obtained by recording a nanodiffraction pattern from each point of the specimen as the incident beams are scanned. An ultrahigh-resolution image is derived by computer processing to give a particular two-dimensional section of this data set. The large amount of data recording and data processing involved with this method may be avoided if the two-dimensional section is derived by recording the hologram while the four beams produced by two perpendicular biprisms are scanned in opposing directions across the specimen by varying the voltages on the biprisms. An equivalent scheme for conventional TEM is also possible. In each case, the complex transmission function of the specimen may be derived and resolutions of about 0.05 nm may be expected.

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Stereological estimation of the size distribution for systems of random convex polyhedrons

Advances in Applied Probability ◽

10.2307/1428053 ◽

1996 ◽

Vol 28 (2) ◽

pp. 340-341

Author(s):

Joachim Ohser ◽

Werner Nagel

Keyword(s):

Size Distribution ◽

Particle Systems ◽

Parameter Distribution ◽

Two Dimensional ◽

Size Parameter ◽

Typical Particle ◽

Dimensional Section ◽

Random Convex

Consider homogeneous spatial particle systems consisting of homothetic particles. Important examples are systems of balls or systems of homothetic convex polyhedrons. For such models the distribution of the typical particle can be expressed by the distribution of one size parameter. We are interested in the stereological estimation of this size parameter distribution from observations on two-dimensional section planes.

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