Determination of gravitational potential for axisymmetric mass-distribution. IV. Some hydrodynamical test results

1987 ◽  
Vol 308 (1) ◽  
pp. 81-86
Author(s):  
R. Tschaepe
Keyword(s):  
Mass Distribution ◽  
Gravitational Potential ◽  
Test Results

Analysis of STEM micrographs of thick objects

1978 ◽  
Vol 36 (2) ◽  
pp. 106-107
Author(s):  
S. Golladay
Keyword(s):  
Inelastic Scattering ◽  
Multiple Scattering ◽  
Mass Distribution ◽  
Cross Sections ◽  
Phase Contrast ◽  
Image Point ◽  
Contrast Effects ◽  
Total Cross Sections ◽  
Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

New approaches for the determination of dextran in the sugar production process

2018 ◽  
pp. 138-146 ◽  
Author(s):  
Karin Abraham ◽  
Eckhard Flöter
Keyword(s):  
Molecular Mass ◽  
Mass Distribution ◽  
Molecular Mass Distribution ◽  
Molecular Size ◽  
Mass Variation ◽  
Negative Effects ◽  
New Approaches ◽  
Precise Knowledge ◽  
Enzyme Application

The presence of polysaccharides in cane and beet raw juices causes several negative effects during the sugar manufacture. These are usually mitigated by enzymatic decomposition of dextrans. Such effects not only depend on the content, but also on the molecular mass distribution. This means that the different dextran fractions specifically affect the process. An accurate process control hence requires the most precise knowledge about the existing content and the molecular mass distribution present. A detailed understanding of the specific processing problems and also a targeted enzyme application hence requires the determination of a total dextran content and also its characterization including the differentiation between the different dextran fractions. An accurate analytical tool which equally satisfies industrial applicability is still lacking. To improve on this situation, two new approaches for the determination of dextran were developed and benchmarked against the commonly used and established Haze Method, which is rather inaccurate and also sensitive to molecular mass variation. The two new approaches are both based on polarimetry. These two methods indicate to be superior over the Haze Method with respect two molecular mass variation and hence enable the determination of a broader molecular size range including also low molecular mass dextrans.

scholarly journals Interaction Boundary Determination of Renewable Energy Sources to Estimate System Strength Using the Power Flow Tracing Strategy

2021 ◽  
Vol 13 (3) ◽  
pp. 1569
Author(s):  
Namki Choi ◽  
Byongjun Lee ◽  
Dohyuk Kim ◽  
Suchul Nam
Keyword(s):  
Renewable Energy ◽  
Power Flow ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Test Results ◽  
Boundary Determination ◽  
Actual Interaction ◽  
Power Flow Tracing ◽  
Estimate System

System strength is an important concept in the integration of renewable energy sources (RESs). However, evaluating system strength is becoming more ambiguous due to the interaction of RESs. This paper proposes a novel scheme to define the actual interaction boundaries of RESs using the power flow tracing strategy. Based on the proposed method, the interaction boundaries of RESs were identified at the southwest side of Korea Electric Power Corporation (KEPCO) systems. The test results show that the proposed approach always provides the identical interaction boundaries of RESs in KEPCO systems, compared to the Electric Reliability Council of Texas (ERCOT) method. The consistent boundaries could be a guideline for power-system planners to assess more accurate system strength, considering the actual interactions of the RESs.

High Strength Combined Support Technology in Deep High Stress Soft Rock Roadway

2012 ◽  
Vol 524-527 ◽  
pp. 598-603
Author(s):  
Nian Jie Ma ◽  
Zhi Qiang Zhao ◽  
Hua Zhao ◽  
Li Shuai Jiang
Keyword(s):  
High Stress ◽  
Soft Rock ◽  
High Strength ◽  
Parameter Determination ◽  
Test Results ◽  
Actual Measurement ◽  
Computer Numerical Simulation ◽  
Soft Rock Roadway ◽  
Rock Roadway

In order to solve the serious damage and repeat revision problem of high stress soft rock roadway in deep -950 level of Tangshan coal mine, based on the theory of the maximum stress level, together with the actual measurement of geostress and the laboratory mechanical parameters of rock-core and computer numerical simulation, the high strength combined support technology and supporting parameters are determined and the engineering test has been done. The engineering test results show that the parameter determination of high strength combined support technology, which based on the actual measurement of geostress, can effective solve the support issue of high stress soft rock roadway and provide useful experience for similar engineering problems.

Experimental and Theoretical Rotordynamic Characteristics of a Hybrid Journal Bearing

1997 ◽  
Vol 119 (1) ◽  
pp. 132-141 ◽  
Author(s):  
J. T. Sawicki ◽  
R. J. Capaldi ◽  
M. L. Adams
Keyword(s):  
Journal Bearing ◽  
Operating Conditions ◽  
Dynamic Force ◽  
Test Results ◽  
Force Measurements ◽  
Lubrication Equation ◽  
Load Cells ◽  
Theoretical Predictions ◽  
Stiffness And Damping

This paper describes an experimental and theoretical investigation of a four-pocket, oil-fed, orifice-compensated hydrostatic bearing including the hybrid effects of journal rotation. The test apparatus incorporates a double-spool-shaft spindle which permits independent control over the journal spin speed and the frequency of an adjustable-magnitude circular orbit, for both forward and backward whirling. This configuration yields data that enables determination of the full linear anisotropic rotordynamic model. The dynamic force measurements were made simultaneously with two independent systems, one with piezoelectric load cells and the other with strain gage load cells. Theoretical predictions are made for the same configuration and operating conditions as the test matrix using a finite-difference solver of Reynolds lubrication equation. The computational results agree well with test results, theoretical predictions of stiffness and damping coefficients are typically within thirty percent of the experimental results.

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