Design of Experiment

2,874 views

Published on

Some examples of scientific experiment design.

Published in: Education

Design of Experiment

  1. 1. The Design of Experiment: Examples Yiming Chen, Oct. 22, 2010
  2. 2. Design of Experiment Phenomena Hypothesis Experiment Theory
  3. 3. Examples • Detonation Test, in World War II • Controlled Experimentation on Scurvy
  4. 4. Detonation Test in WW II 1. E.B. Wilson, The analysis of experimental data, An Introduction to Scientific Research, McGraw- Hill, New York (1952) 2. http://en.wikipedia.org/wiki/Explosive_material
  5. 5. Detonation Test • Factors of Explosion • Chemical composition; • Initiator; • Shape of explosive shell; • Material of explosive shell; • ………………
  6. 6. Detonation Test Too Complicated to study!
  7. 7. Detonation Test Cylinder Expansion Test: An Simplified Model • Standard amount of explosive is loaded into a long hollow cylinder; • Detonated at one end; • Data is collected concerning the rate of radial expansion of the cylinder wall;
  8. 8. Cylinder Expansion Test
  9. 9. Simplified Ideal Model • Simplification: Remove variables by ideal Model; • Standardization: Comparative and Repeatable;
  10. 10. Simplified Ideal Model Powerful tool to study fundamental mechanism in detail.
  11. 11. Experiment on Scurvy 1. http://en.wikipedia.org/wiki/ Design_of_experiments 2. http://en.wikipedia.org/wiki/Scurvy 3. James Lind (1716-94) of Edinburgh and the treatment of scurvy, Arch Dis Child Fetal Neonatal Ed 1997;76:F64-F65
  12. 12. Experiment on Scurvy • Scurvy was at one time common among sailors due to lacking of fresh vegetables & fruits; • Described by Hippocrates (460 BC–380 BC), and partially cured by herbal in many native cultures; • Killing large numbers of the passengers and crew on long-distance voyages.
  13. 13. Experiment on Scurvy • James Lind carried out a controlled experiment to develop a cure for scurvy. - 12 men selected, all suffering from scurvy; - Divided into six pairs, giving different additions to their basic diet for a period of two weeks;
  14. 14. Experiment on Scurvy
  15. 15. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  16. 16. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  17. 17. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  18. 18. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  19. 19. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  20. 20. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  21. 21. Experiment on Scurvy Pair Additional Food 1 A quart of cider 2 Drops of Sulfuric Acid 3 1.5 pint of seawater 4 Garlic, mustard, horseradish 5 Spoons of Vinegar 6 Oranges and Lemons
  22. 22. Experiment on Scurvy Pair Additional Food 1 A quart of cider No comparable improvement 2 Drops of Sulfuric Acid No comparable improvement 3 1.5 pint of seawater No comparable improvement 4 Garlic, mustard, horseradish No comparable improvement 5 Spoons of Vinegar No comparable improvement 6 Oranges and Lemons Recovered within week
  23. 23. Scurvy Experiment • Conclusion: Scurvy could be cured by Citrus fruits; • Mechanism: resulting from a deficiency of vitamin C, which is required for the synthesis of collagen in humans.
  24. 24. Scurvy Experiment But ......
  25. 25. Scurvy Experiment • He fed patients with H SO , seawater: lacking 2 4 of proper knowledge; • Additional foods are pre-assigned to patients: missing randomized allocation of subjects to treatments.
  26. 26. Controlled Experimentation • Compare experimental sample against controlled sample; • Controlled sample is identical to experimental sample except the variable need to be tested (independent variable);
  27. 27. Don’t Leave It'll be more appealing later!

×