Error, Falsification and Scientific Inference: An Experimental Investigation

1989 ◽  
Vol 41 (2) ◽  
pp. 385-412 ◽  
Author(s):  
Michael E. Gorman
Keyword(s):  
Experimental Investigation ◽  
Scientific Reasoning ◽  
Experimental Results ◽  
Current Trial ◽  
Control Subjects ◽  
Scientific Inference ◽  
Actual Error ◽  
Error Condition

This paper reports the results of four experiments designed to test the methodological falsificationist's assumption that replication is sufficient to prevent the possibility of error from being used to immunize hypotheses against disconfirmation. The first three experiments compare the performance of subjects on tasks that simulate scientific reasoning under two conditions: (1) where there is a 0–20% possibility of error in experimental results, but no actual error; and (2) a control condition. All experiments used Wason's 2–4–6 task, in which subjects propose triples and are told whether each corresponds to a rule. In Experiment 1, subjects in the possible-error condition proposed significantly more triples than control subjects. Experiment 2 added colour and letter dimensions to the 2–4–6 task; possible-error subjects proposed significantly more triples and replicated the same triple more often than control subjects. Experiment 3 made replication more difficult by limiting the number of experiments subjects could perform and by altering the rule to make the results of the current trial dependent on previous ones. Control subjects solved this problem significantly more often than possible-error subjects. Experiment 4 was run in a manner very similar to Experiment 1, except that an actual 20% error condition was added. Subjects in this condition solved the rule significantly less often than subjects in other conditions, and also took more time and replicated more often. Implications of these results for the methodological falsificationist's position are discussed.

Experimental Investigation of Strengthening and Polishing Aeroengine Blades

2011 ◽  
Vol 101-102 ◽  
pp. 909-912
Author(s):  
Guo Ying Zeng ◽  
Deng Feng Zhao
Keyword(s):  
Surface Roughness ◽  
Experimental Investigation ◽  
Fatigue Strength ◽  
Surface Quality ◽  
Three Dimensional ◽  
Experimental Results ◽  
Technological Parameters ◽  
Polishing Process ◽  
Optimum Parameters ◽  
The Media

The three-dimensional vibratory strengthening and polishing technology was used to strengthen and polish aeroengine blades with complicated surfaces. At first, the principle of the strengthening and polishing process was introduced, which combined strengthening process with polishing process. Then, the technological parameters influenced on the surface quality were investigated. The principal variables were the media hardness, the frequency and amplitude of the vibration, and duration of the vibratory strengthening and polishing. The optimum parameters were obtained. Experimental results revealed that, after strengthening and polishing, the surface roughness of aeroengine blades was reduced from Ra0.35-0.5μm to Ra0.1-0.12μm, and fatigue strength was increased by approximately 50%.

Experimental Investigation of Flowrate Irregularity in Rotary Gear Pumps

1992 ◽  
Author(s):  
G. Mimmi
Keyword(s):  
Experimental Investigation ◽  
Flow Rate ◽  
Experimental Tests ◽  
Periodic Variation ◽  
Experimental Results ◽  
Gear Pump ◽  
Gear Pumps ◽  
Hot Film ◽  
Instantaneous Flow Rate ◽  
External Gear Pump

Abstract In a previous paper the author proposed a method to reduce the periodic variation in flow rate for an external gear pump. To verify the experimental results, a series of experimental tests on a expressly realized gear pump, was carried out. The pump was equipped with relieving grooves milled into the side plates. The tests were done on a closed piping specifically realized and equipped for measuring the instantaneous flow rate of the fluid through a wedge-shaped hot film probe.

An Experimental Investigation for Flow Past a Circular Cylinder With Rectangular Strips

2002 ◽  
Author(s):  
Chuan He ◽  
Tianyu Long ◽  
Mingdao Xin ◽  
Benjamin T. F. Chung
Keyword(s):  
Experimental Investigation ◽  
Fluid Flow ◽  
Circular Cylinder ◽  
Drag Coefficient ◽  
Experimental Results ◽  
Sharp Edge ◽  
Flow Past ◽  
Rectangular Strips

This paper reports an experimental investigation for fluid flow past a circular cylinder with two small rectangular strips and single sharp-edge strips on its surface. The experimental results reflected that different arrangements or dimensions of the strips produced significantly different effects on the flow. The forward step caused a stronger disturbance with a small increase in drag. The backward step arrangement softened the disturbance but reduced the drag coefficient by 33%.

Experimental Investigation of the Maximum Heat Transport in Triangular Grooves

1996 ◽  
Vol 118 (3) ◽  
pp. 740-746 ◽  
Author(s):  
H. B. Ma ◽  
G. P. Peterson
Keyword(s):  
Experimental Investigation ◽  
Heat Transport ◽  
Heat Pipes ◽  
Effective Area ◽  
Experimental Results ◽  
Test Facility ◽  
Working Fluid ◽  
Maximum Heat ◽  
Pressure Losses ◽  
Micro Heat Pipes

An experimental investigation was conducted and a test facility constructed to measure the capillary heat transport limit in small triangular grooves, similar to those used in micro heat pipes. Using methanol as the working fluid, the maximum heat transport and unit effective area heat transport were experimentally determined for ten grooved plates with varying groove widths, but identical apex angles. The experimental results indicate that there exists an optimum groove configuration, which maximizes the capillary pumping capacity while minimizing the combined effects of the capillary pumping pressure and the liquid viscous pressure losses. When compared with a previously developed analytical model, the experimental results indicate that the model can be used accurately to predict the heat transport capacity and maximum unit area heat transport when given the physical characteristics of the working fluid and the groove geometry, provided the proper heat flux distribution is known. The results of this investigation will assist in the development of micro heat pipes capable of operating at increased power levels with greater reliability.

Nucleation Phenomena in Flowing High-Pressure Steam: Experimental Results

1989 ◽  
Vol 203 (3) ◽  
pp. 195-200 ◽  
Author(s):  
F Bakhtar ◽  
K Zidi
Keyword(s):  
Experimental Investigation ◽  
High Pressure ◽  
Test Section ◽  
Experimental Results ◽  
Axial Pressure ◽  
High Pressure Steam ◽  
Pressure Distributions ◽  
Pressure Steam

The paper describes the results of an experimental investigation of limiting supersaturation in high-pressure steam. It follows an earlier investigation and to avoid the uncertainties associated with leakage past sliding profiles, the test section has been redesigned and the measurements taken with fixed nozzles. Three convergent-divergent nozzles with nominal rates of expansion of 3000, 5000 and 10000 per second have been used and the inlet stagnation pressures cover the range 25–35 bar. The data consist mainly of axial pressure distributions but some droplet measurements have also been recorded.

scholarly journals Experimental Investigation on Influence of Shed Parameters on Surface Rainwater Characteristics of Large-Diameter Composite Post Insulators under Rain Conditions

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5011
Author(s):  
Yanpeng Hao ◽  
Yifan Liao ◽  
Zhiqiang Kuang ◽  
Yijie Sun ◽  
Gaofeng Shang ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Heavy Rainfall ◽  
Rainfall Intensity ◽  
Large Diameter ◽  
Quantitative Description ◽  
Experimental Results ◽  
Water Droplets ◽  
Insulator Surface ◽  
Water Columns ◽  
Artificial Rain

The discharges of water columns and droplets between the sheds make the leakage distance not effectively used, which is one of the main reasons for flashover of composite post insulators under heavy rainfall. To study the influence of shed parameters on surface rainwater characteristics, artificial rain tests were carried out on the large-diameter composite post insulators under the rainfall intensity of 2–15 mm/min. Lwc (the length of water columns at the edge of large sheds), Nwc (the number of water columns at the edge of large sheds), Nwde (the number of water droplets at the edge of large sheds) and Nwds (the number of water droplets in the space between two adjacent large sheds) were proposed as the parameters of surface rainwater characteristics. The influences of large shed spacing, large shed overhang and rod diameter on the parameters of surface rainwater characteristics under different rainfall intensities were analyzed. The experimental results show that, under the same rainfall intensity, with the rise in large shed spacing, large shed overhang or rod diameter, Lwc, Nwc, Nwde and Nwds all increase. Under different rainfall intensities, the trends of the parameters with the change in shed parameters are basically invariant; however, the change ranges of the parameters are different. The increases in the parameters with the rises in shed parameters and rainfall intensity are mainly attributed to the change in the rainfall on the insulator surface. The experimental results can provide references for the quantitative description of surface rainwater characteristics and the design of large-diameter composite post insulators for DC transmission systems.

scholarly journals Experimental investigation on shear properties of warp-knitted brush fabrics

2020 ◽  
Vol 15 ◽  
pp. 155892502094645
Author(s):  
Yao Chu ◽  
Haitao Lin ◽  
Hafsa Jamshaid ◽  
Qi Zhang ◽  
Pibo Ma
Keyword(s):  
Experimental Investigation ◽  
Shear Strength ◽  
Outer Surface ◽  
Shear Force ◽  
Shear Resistance ◽  
Experimental Results ◽  
Shear Properties ◽  
Factors Affecting ◽  
Car Seat ◽  
Seat Cushions

Warp-knitted brush fabrics are composed of an outer surface formed by weaving the front and rear needle beds with spacer yarns interposed between them. Warp-knitted brush fabrics can be used as a non-slip cover for car seat cushions; the adhesion between non-slip fabric and car seat is related to the shear strength of warp-knitted brush fabrics. In this article, to study the factors affecting the shear force of warp-knitted brush fabrics, three different processing methods and four different stretching speed intervals were used to find the effects of stiffeners and action of different speed intervals on shear properties of fabrics. The experimental results show that the stiffener treatment can improve the shear resistance of the warp-knitted brush fabrics, and the effect of different speed intervals can affect the shear resistance of fabrics. These findings will have a guiding significance in the design and production of warp-knitted brush fabrics applied to fabrics such as car seat cushions, and the results can also help to study the shear properties of warp-knitted brush fabrics for wider applications.

scholarly journals Experimental investigation of a single-degree-of-freedom system with Coulomb friction

2020 ◽  
Vol 99 (3) ◽  
pp. 1781-1799
Author(s):  
Luca Marino ◽  
Alice Cicirello
Keyword(s):  
Experimental Investigation ◽  
Degree Of Freedom ◽  
Experimental Results ◽  
Systematic Observation ◽  
Stick Slip ◽  
Friction Forces ◽  
Single Degree Of Freedom ◽  
Sdof System ◽  
Single Degree ◽  
Set Up

AbstractThis paper presents an experimental investigation of the dynamic behaviour of a single-degree-of-freedom (SDoF) system with a metal-to-metal contact under harmonic base or joined base-wall excitation. The experimental results are compared with those yielded by mathematical models based on a SDoF system with Coulomb damping. While previous experiments on friction-damped systems focused on the characterisation of the friction force, the proposed approach investigates the steady response of a SDoF system when different exciting frequencies and friction forces are applied. The experimental set-up consists of a single-storey building, where harmonic excitation is imposed on a base plate and a friction contact is achieved between a steel top plate and a brass disc. The experimental results are expressed in terms of displacement transmissibility, phase angle and top plate motion in the time and frequency domains. Both continuous and stick-slip motions are investigated. The main results achieved in this paper are: (1) the development of an experimental set-up capable of reproducing friction damping effects on a harmonically excited SDoF system; (2) the validation of the analytical model introduced by Marino et al. (Nonlinear Dyn, 2019. https://doi.org/10.1007/s11071-019-04983-x) and, particularly, the inversion of the transmissibility curves in the joined base-wall motion case; (3) the systematic observation of stick-slip phenomena and their validation with numerical results.

An Experimental Investigation of Heat Transfer in Variable Porosity Media

1985 ◽  
Vol 107 (3) ◽  
pp. 642-647 ◽  
Author(s):  
K. Vafai ◽  
R. L. Alkire ◽  
C. L. Tien
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Packed Bed ◽  
Volume Averaging ◽  
Experimental Results ◽  
Variable Porosity ◽  
Local Volume Averaging ◽  
Convection In Porous Media ◽  
Impermeable Boundary ◽  
Good Agreement

This paper presents an experimental investigation on the effects of a solid impermeable boundary and variable porosity on forced convection in porous media. Emphasis is placed on the channeling effects on heat transfer in packed beds. The local volume-averaging technique is used to establish the governing equations and a numerical scheme is developed which incorporates the boundary and variable porosity effects on heat transfer. The experimental results for the heat flux at the boundary are presented as a function of the pertinent variables in a packed bed. The Nusselt number is found to increase almost linearly with an increase in the Reynolds number based on the pore diameter. The experimental results are found to be in good agreement with the theoretical results which account for the variable porosity effects. A comparison between the numerical and the experimental results demonstrates the importance of boundary and variable porosity effects on heat transfer in variable porosity media.

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