Scientific communication_presentation.ppt

Fatigue is the Initiation, formation and propagation of cracks in a material due to cyclic loads. The failure occurs due to the cyclic nature of the load which causes microscopic material imperfections to grow into a macroscopic crack. This phenomenon mainly happens but due to multiple load cycles which causes components to lose their strength and get tired, hence it is called fatigue.
Once a fatigue crack has initiated, it grows a small amount with each loading cycle and it will continue to grow until it reaches a critical size, which occurs when the stress intensity factor of the crack exceeds the fracture toughness of the material, producing rapid propagation and typically complete fracture of the structure.
Scientific communication_presentation.ppt

1. Scientific Communication and
Technological Failure
presentation for ILTM, July 9,
1998
Dan Little

2. Topics

Scientific communication and visual
reasoning

Failure in large technology systems

The central role of effective scientific
communication in technology
management

3. Edward Tufte, theorist of
scientific graphics

A political scientist who has provided a
high standard for evaluating, designing,
and criticizing scientific graphics

The Visual Display of Quantitative
Information (1983)

Visual Explanations (1997)

4. Tufte’s program
“Modern data graphics can do much
more than simply substitute for small
statistical tables. At their best, graphics
are instruments for reasoning about
quantitative information. Often the most
effective way to describe, explore, and
summarize a set of numbers -- even a
very large set -- is to look at pictures of
those numbers.” (VDQI, p. 9)

5. Tufte’s program

“Assessments of change, dynamics,
and cause and effect are at the heart of
thinking and explanation. To
understand is to know what cause
provokes what effect, by what means,
at what rate. How then is such
knowledge to be represented?” (VE, p.
9)

6. The critique
Tufte finds that much graphic
communication is faulty, both in the
popular press and in scientific and
technical publications. He urges that
we develop more sophisticated
standards of graphical communication,
and adhere to those standards as an
element of good thinking and good
science.

7. The Challenger disaster

The data

The analysis

The inference and conclusion

The presentation

8. Tufte’s diagnosis
Tufte argues that a crucial failure in the
sequence of analysis, communication,
and persuasion that led up to the
Challenger disaster was critically flawed
scientific communication. The Thiokol
engineers reached the right conclusion;
but they couched their findings in
scientific documents that failed to make
the case for non-scientists.

9. O-Ring Data

10. Bad View (1)

11. Bad view (2)

12. The Good View

13. Importance of scientific
communication
engineers and technical specialists
need to communicate technical issues
effectively to non-specialists
managers need accurate information
managers need clear understanding of
technology choices and alternatives
managers need to be able to make
appropriate inferences and predictions

14. Varieties of scientific
communication

graphs and charts

maps / GIS analysis

technical reports / recommendations

statistical analysis

15. Data tables
What is quantitative reasoning?
time series--stock prices, blood pressure
bivariate associations -- sunspots and
weather, tension and fracture, economic
growth and population growth
multivariate associations -- rainfall, fertilizer,
sunshine, pesticide, crop yield
tools: regression, correlation, spatial analysis
rates vs aggregate amounts

16. data plot

17. China Famine
0.00
10.00
20.00
30.00
40.00
50.00
60.00
1957 1958 1959 1960 1961 1962
Sichuan
Guizhou

18. Stomach cancer

19. Napoleon’s Army

20. Wine Trade

21. What is conveyed in a
scientific graphic?
Analysis, hypothesis formation, and
presentation
Information content
density of information--data set and
graphic representation
presentation of causal relations among
variables in a data set
analysis of patterns implicit in a data set

22. Scientific graphics and
scientific method

analysis -- probe data to discover
patterns and associations

explanation

causal inquiry

hypotheses and confirmation; induction,
deduction, abduction

validity and scientific method

23. Data Table

24. statistics

25. Data Plot

26. Examples of good scientific
communication

Cholera inference

spatial analysis of economic and social
data

GIS software

scatter plot to demonstrate causal
connections

27. Failures of scientific
communication

Challenger disaster

air crash in Columbia (navigation
software which gave same label to two
beacons)

software failure: implementation of US
design standards into CAD software for
industrial buildings

28. The cholera case

The difficulty of analysis: what variables
are significant?

spatial analysis

importance of scale of analysis

29. What standards should govern
scientific graphics?
accuracy of content
easy to read
analytical insight--reveal previously
unidentified patterns
easy to make appropriate inferences
easy to read scale, data limitations
Inference and communication --
separate functions

30. Tufte’s principles of graphical
excellence

well-designed presentation of
interesting data

complex ideas communicated with
clarity, precision, and efficiency

gives to the viewer the greatest number
of ideas in the shortest time with the
least ink in the smallest space

31. Tufte’s principles (cont.)

nearly always multivariate

tell the truth about the data

do not quote data out of context (74)

32. Chart junk

excessive ink

“cute” elements

unnecessary data labels

33. The Bad View

34. The Good View