Metrological Characteristics Analysis of Measuring Means for Distributed Mobile Measuring System on the Base of Reference Model of an Object

2020 ◽  
Author(s):  
Vladimir V. Alekseev ◽  
Pavel G. Korolev ◽  
Natalya V. Orlova ◽  
Dmitry V. Pimenov
Keyword(s):  
Reference Model ◽  
Metrological Characteristics ◽  
Measuring System ◽  
Characteristics Analysis

Joint Modeling of DFIG-Based Wind Turbines for Structural Load Characteristics Analysis

2012 ◽  
Vol 588-589 ◽  
pp. 1386-1389
Author(s):  
Zhan Feng Song ◽  
Qiang Geng
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Simulation Modeling ◽  
Reference Model ◽  
Joint Modeling ◽  
Modeling Method ◽  
Complete Model ◽  
Simulation Strategy ◽  
Characteristics Analysis ◽  
Load Characteristics

To study the structural loads of wind turbines under grid faults, this paper introduces the concept of co-simulation in the load characteristics analysis of wind turbines under voltage dips and a complete model including both mechanical and electrical parts is constructed. A combination of different simulation packages is used to model the electrical and mechanical aspects of a wind turbine respectively. To demonstrate the co-simulation modeling method can be applied to analyze wind turbine structures, a reference model based on the industry-accepted wind turbine analysis code is also established. A side-by-side comparison of response predictions is further performed between co-simulation strategy and industry-accepted wind turbine analysis code.

Displacement Sensor with Controlled Measuring Force and its Characteristics Analysis

2011 ◽  
Vol 103 ◽  
pp. 309-313
Author(s):  
Liang En Yang ◽  
Xuan Ze Wang ◽  
Lin Zheng
Keyword(s):  
Surface Topography ◽  
Voice Coil Motor ◽  
Theory Model ◽  
Measuring System ◽  
Displacement Sensor ◽  
Electric Induction ◽  
Induction Transducer ◽  
Characteristics Analysis ◽  
Measuring Force ◽  
Bearing Ball

A displacement sensor with controlled measuring force and its characteristics analysis are discussed in this paper. The displacement sensor consists of an electric induction transducer with high resolution and a voice coil motor (VCM). The measuring principles, structure of the sensor are discussed. Theory model, dynamic and static characteristics of VCM are analysed. A measuring system for surface topography with large measuring range is constructed based on the displacement sensor and 2D moving platform. Measuring force of the sensor in measurement process of surface topography can be controlled at μN level and hardly changes. It has been used in measurement of bearing ball，bullet mark, etc.

scholarly journals Measuring System for Non-Destructive Testing of Metal Rods

2020 ◽  
pp. 22-24
Author(s):  
D. P. Ornatsky ◽  
O. O. Krivokulska ◽  
O. O. Burbela ◽  
O. D. Bliznyuk
Keyword(s):  
Nondestructive Testing ◽  
Electromagnetic Induction ◽  
High Sensitivity ◽  
Wide Frequency Range ◽  
Metrological Characteristics ◽  
Measuring System ◽  
Time Signal ◽  
Production Environment ◽  
Frequency Range ◽  
Metal Products

The control parameters of metal products using the eddy current method of nondestructive testing based on electromagnetic induction law is now widespread. Due to the high sensitivity over a wide frequency range of the ability to control the mechanical properties , uniformity of material, both magnetic and non-magnetic materials, beskonechnosti, high reliability, automation, process control, etc. The object of study is the process of interaction of external electromagnetic fields with defects in heterogeneity of structure in metal rod, causing a deformation of microtubuli currents and, accordingly, their influence on the inductance coil of the sensor. So, according to the law of electromagnetic induction eddy currents induced by an external electromagnetic field will be asking a private field that will oppose the external field that will lead to a change in inductance of the sensor coil. Therefore, the most informative parameter in this case is the relative change in inductance of the sensor. In the known designs use differential transformer sensors, transmission type, which differ in complexity of implementation, but have high sensitivity. In existing works not enough attention on improving of the metrological characteristics . Modern means of microstraava flaw detectors in the overwhelming number are for scientific research, but little attention is paid to tools that can be used in industrial processes, through a complex measurement process in the existing funds and the large volume of the software during automatic processing of information. In the presented work there is a system for nondestructive testing of metal bars with deprivation of the above-mentioned disadvantages, which would provide high metrological characteristics in a wide frequency range, separate measurement of impedance components of the sensor, which allows the reduction of methodological errors of determination of the main characteristics of the output signal of microstraava sensors. The scientific result is created sambalanco pavement system based on electronic dharamtala model of a vortex sensor with high metrological characteristics, which allows you to create real-time signal proportional to the amount of damage that will give you the opportunity to increase productivity in the quality control bar of metal products in a production environment.

scholarly journals Measurement of Aerodynamic Characteristics Using Cinder Models through Free Fall Experiment

Atmosphere ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 608
Author(s):  
Meizhi Liu ◽  
Takashi Maruyama ◽  
Kansuke Sasaki ◽  
Minoru Inoue ◽  
Masato Iguchi ◽  
...  
Keyword(s):  
Reference Model ◽  
Volcanic Rocks ◽  
Three Dimensional ◽  
Free Fall ◽  
Video Camera ◽  
Aerodynamic Characteristics ◽  
Measuring System ◽  
Deviation Angle ◽  
Force Direction ◽  
Sharp Edges

Rocks ejected from a volcanic eruption often cause loss of lives and structures. Aerodynamic characteristics are needed for evaluating motions of volcanic rocks for the reduction of damage. Falling motions of volcanic rock were measured by using models imitated the configuration of cinders collected at the site of the experiment, Sakurajima volcano. Two types, one with sharp edges and one without sharp edges, were selected as representative of cinder and a sphere was selected as reference model. The falling motions of the models dropped down from a drone were recorded by video camera and a stand-alone measuring system that included a pressure sensor, acceleration and angular velocity sensors in the models. The motion, posture, velocity and acceleration of the model were obtained in order to measure the three-dimensional falling trajectory. The drag and the deviation angle between relative wind direction and wind force direction were examined. The variation of the drag coefficient and the deviation angle with Reynolds number was clarified.

Die Spezifität von Begabungsüberzeugungen als Determinante des verbalen und mathematischen Begabungsselbstkonzepts

2002 ◽  
Vol 16 (2) ◽  
pp. 87-97 ◽  
Author(s):  
Jens Möller ◽  
Britta Pohlmann ◽  
Lilian Streblow ◽  
Julia Kaufmann
Keyword(s):  
Reference Model ◽  
Frame Of Reference ◽  
External Frame

Zusammenfassung: Das I/E-Modell (“Internal/External Frame of Reference Model”) von Marsh (1986) postuliert, dass Schülerinnen und Schüler dimensionale Vergleiche der eigenen Leistungen in einem Fach mit den Leistungen in einem anderen Fach anstellen. Diese Vergleiche führen dazu, dass z. B. Schüler mit guten Leistungen in Mathematik ihre verbalen Fähigkeiten niedriger einschätzen. Gegenstand dieser Untersuchung mit N = 1114 Probanden ist die Frage, ob die Überzeugungen von Personen zum Zusammenhang von mathematischer und verbaler Begabung die Effekte dimensionaler Vergleiche moderieren. Analysen zeigten die Bedeutung der Begabungsüberzeugungen der Schülerinnen und Schüler: Negative Zusammenhänge zwischen den Fachleistungen in einem Fach und dem akademischen Selbstkonzept in einem anderen Fach ergaben sich insbesondere für Personen, die annehmen, dass Begabung domänenspezifisch ist, man also entweder mathematisch oder sprachlich begabt ist. Für Schüler mit eher wenig spezifischer Begabungsüberzeugung ergaben sich geringere Effekte dimensionaler Vergleiche.

Development and Evaluation of Fuzzy Criteria for the Diagnosis of Rheumatoid Arthritis

1996 ◽  
Vol 35 (04/05) ◽  
pp. 334-342 ◽  
Author(s):  
K.-P. Adlassnig ◽  
G. Kolarz ◽  
H. Leitich
Keyword(s):  
Rheumatoid Arthritis ◽  
Reference Model ◽  
American Rheumatism Association ◽  
Uniform Definition ◽  
Sensitivity Rate ◽  
Fuzzy Techniques ◽  
Definition Of ◽  
Different Levels ◽  
Specificity Rate

Abstract:In 1987, the American Rheumatism Association issued a set of criteria for the classification of rheumatoid arthritis (RA) to provide a uniform definition of RA patients. Fuzzy set theory and fuzzy logic were used to transform this set of criteria into a diagnostic tool that offers diagnoses at different levels of confidence: a definite level, which was consistent with the original criteria definition, as well as several possible and superdefinite levels. Two fuzzy models and a reference model which provided results at a definite level only were applied to 292 clinical cases from a hospital for rheumatic diseases. At the definite level, all models yielded a sensitivity rate of 72.6% and a specificity rate of 87.0%. Sensitivity and specificity rates at the possible levels ranged from 73.3% to 85.6% and from 83.6% to 87.0%. At the superdefinite levels, sensitivity rates ranged from 39.0% to 63.7% and specificity rates from 90.4% to 95.2%. Fuzzy techniques were helpful to add flexibility to preexisting diagnostic criteria in order to obtain diagnoses at the desired level of confidence.

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