45 CFR 1230.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

44 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

32 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

24 CFR 87.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... professional or technical discipline. For example, drafting of a legal document accompanying a bid or proposal... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

44 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

38 CFR 45.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

24 CFR 87.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-04-01

... professional or technical discipline. For example, drafting of a legal document accompanying a bid or proposal... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

41 CFR 105-69.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... or technical discipline. For example, drafting or a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

45 CFR 1230.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

41 CFR 105-69.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... or technical discipline. For example, drafting or a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

38 CFR 45.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

45 CFR 1230.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

41 CFR 105-69.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... or technical discipline. For example, drafting or a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

38 CFR 45.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

32 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

29 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... professional or technical discipline. For example, drafting of a legal document accompanying a bid or proposal... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

41 CFR 105-69.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

44 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... any professional or technical discipline. For example, drafting of a legal document accompanying a bid..., communications with the intent to influence made by an engineer providing an engineering analysis prior to the...

38 CFR 45.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

... or technical discipline. For example, drafting of a legal document accompanying a bid or proposal by... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

29 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... professional or technical discipline. For example, drafting of a legal document accompanying a bid or proposal... the intent to influence made by an engineer providing an engineering analysis prior to the preparation...

44 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

14 CFR 1271.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

32 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... technical discipline. For example, drafting of a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

38 CFR 45.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

24 CFR 87.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

24 CFR 87.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

45 CFR 604.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

44 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

38 CFR 45.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 712.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

31 CFR 21.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

45 CFR 1230.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

14 CFR 1271.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

32 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... technical discipline. For example, drafting of a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 311.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

29 CFR 93.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 712.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

45 CFR 604.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 311.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

40 CFR 34.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

38 CFR 45.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

24 CFR 87.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

18 CFR 1315.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 311.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

31 CFR 21.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

45 CFR 604.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

44 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

22 CFR 712.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

32 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... technical discipline. For example, drafting of a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

31 CFR 21.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

40 CFR 34.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

29 CFR 93.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

31 CFR 21.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

40 CFR 34.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

45 CFR 1230.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... technical discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

29 CFR 93.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

First-Year Engineering Students' Views of the Nature of Engineering: Implications for Engineering Programmes

ERIC Educational Resources Information Center

Karatas, F. Ö.; Bodner, G. M.; Unal, Suat

2016-01-01

A study was conducted on the views of the nature of engineering held by 114 first-year engineering majors; the study built on prior work on views of the nature of science held by students, their instructors, and the general public. Open-coding analysis of responses to a 12-item questionnaire suggested that the participants held tacit beliefs that…

14 CFR § 1271.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... discipline. For example, drafting or a legal document accompanying a bid or proposal by a lawyer is allowable... influence made by an engineer providing an engineering analysis prior to the preparation or submission of a...

10 CFR 601.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

10 CFR 601.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

10 CFR 601.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

10 CFR 601.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.23 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 311.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

10 CFR 601.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1158.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... analysis directly applying any professional or technical discipline. For example, drafting of a legal... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 311.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.23 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.23 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.23 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

49 CFR 20.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1158.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... limited to advice and analysis directly applying any professional or technical discipline. For example... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

7 CFR 3018.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 138.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... analysis directly applying any professional or technical discipline. For example, drafting of a legal... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

... analysis directly applying any professional or technical discipline. For example, drafting of a legal... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 311.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting of a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1158.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1168.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

10 CFR 601.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 227.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

20 CFR 438.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 519.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

... and analysis directly applying any professional or technical discipline. For example, drafting or a... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... advice and analysis directly applying any professional or technical discipline. For example, drafting of... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

Practical quality control tools for curves and surfaces

NASA Technical Reports Server (NTRS)

Small, Scott G.

1992-01-01

Curves (geometry) and surfaces created by Computer Aided Geometric Design systems in the engineering environment must satisfy two basic quality criteria: the geometric shape must have the desired engineering properties; and the objects must be parameterized in a way which does not cause computational difficulty for geometric processing and engineering analysis. Interactive techniques are described which are in use at Boeing to evaluate the quality of aircraft geometry prior to Computational Fluid Dynamic analysis, including newly developed methods for examining surface parameterization and its effects.

43 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.15 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 604.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

18 CFR 1315.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

18 CFR 1315.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 604.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

28 CFR 69.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

13 CFR 146.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

31 CFR 21.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.15 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

18 CFR 1315.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 712.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

40 CFR 34.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 712.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

40 CFR 34.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

31 CFR 21.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-10-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

14 CFR 1271.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1158.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

13 CFR 146.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

31 CFR 21.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 604.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

43 CFR 18.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

14 CFR 1271.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

6 CFR 9.15 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

40 CFR 34.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

15 CFR 28.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-01-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

18 CFR 1315.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

28 CFR 69.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-10-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

13 CFR 146.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 1158.300 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

45 CFR 1158.300 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

6 CFR 9.15 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-10-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

22 CFR 712.205 - Professional and technical services.

Code of Federal Regulations, 2012 CFR

2012-04-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

45 CFR 93.205 - Professional and technical services.

Code of Federal Regulations, 2013 CFR

2013-10-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.300 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

14 CFR 1271.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

12 CFR 411.300 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

... analysis directly applying any professional or technical discipline. For example, drafting or a legal... engineering analysis prior to the preparation or submission of a bid or proposal are not allowable under this...

31 CFR 21.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-07-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

13 CFR 146.205 - Professional and technical services.

Code of Federal Regulations, 2011 CFR

2011-01-01

... shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

23 CFR 627.5 - Applicable projects.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 23 Highways 1 2013-04-01 2013-04-01 false Applicable projects. 627.5 Section 627.5 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING § 627.5 Applicable projects. (a) A VE analysis shall be conducted prior to the completion of final...

23 CFR 627.5 - Applicable projects.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 23 Highways 1 2014-04-01 2014-04-01 false Applicable projects. 627.5 Section 627.5 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING § 627.5 Applicable projects. (a) A VE analysis shall be conducted prior to the completion of final...

Engineering risk reduction in satellite programs

NASA Technical Reports Server (NTRS)

Dean, E. S., Jr.

1979-01-01

Methods developed in planning and executing system safety engineering programs for Lockheed satellite integration contracts are presented. These procedures establish the applicable safety design criteria, document design compliance and assess the residual risks where non-compliant design is proposed, and provide for hazard analysis of system level test, handling and launch preparations. Operations hazard analysis identifies product protection and product liability hazards prior to the preparation of operational procedures and provides safety requirements for inclusion in them. The method developed for documenting all residual hazards for the attention of program management assures an acceptable minimum level of risk prior to program deployment. The results are significant for persons responsible for managing or engineering the deployment and production of complex high cost equipment under current product liability law and cost/time constraints, have a responsibility to minimize the possibility of an accident, and should have documentation to provide a defense in a product liability suit.

14 CFR § 1271.205 - Professional and technical services.

Code of Federal Regulations, 2014 CFR

2014-01-01

...” shall be limited to advice and analysis directly applying any professional or technical discipline. For... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

Interactive Finite Elements for General Engine Dynamics Analysis

NASA Technical Reports Server (NTRS)

Adams, M. L.; Padovan, J.; Fertis, D. G.

1984-01-01

General nonlinear finite element codes were adapted for the purpose of analyzing the dynamics of gas turbine engines. In particular, this adaptation required the development of a squeeze-film damper element software package and its implantation into a representative current generation code. The ADINA code was selected because of prior use of it and familiarity with its internal structure and logic. This objective was met and the results indicate that such use of general purpose codes is viable alternative to specialized codes for general dynamics analysis of engines.

A controls engineering approach for analyzing airplane input-output characteristics

NASA Technical Reports Server (NTRS)

Arbuckle, P. Douglas

1991-01-01

An engineering approach for analyzing airplane control and output characteristics is presented. State-space matrix equations describing the linear perturbation dynamics are transformed from physical coordinates into scaled coordinates. The scaling is accomplished by applying various transformations to the system to employ prior engineering knowledge of the airplane physics. Two different analysis techniques are then explained. Modal analysis techniques calculate the influence of each system input on each fundamental mode of motion and the distribution of each mode among the system outputs. The optimal steady state response technique computes the blending of steady state control inputs that optimize the steady state response of selected system outputs. Analysis of an example airplane model is presented to demonstrate the described engineering approach.

Predicting on-site environmental impacts of municipal engineering works

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gangolells, Marta, E-mail: marta.gangolells@upc.edu; Casals, Miquel, E-mail: miquel.casals@upc.edu; Forcada, Núria, E-mail: nuria.forcada@upc.edu

2014-01-15

The research findings fill a gap in the body of knowledge by presenting an effective way to evaluate the significance of on-site environmental impacts of municipal engineering works prior to the construction stage. First, 42 on-site environmental impacts of municipal engineering works were identified by means of a process-oriented approach. Then, 46 indicators and their corresponding significance limits were determined on the basis of a statistical analysis of 25 new-build and remodelling municipal engineering projects. In order to ensure the objectivity of the assessment process, direct and indirect indicators were always based on quantitative data from the municipal engineering projectmore » documents. Finally, two case studies were analysed and found to illustrate the practical use of the proposed model. The model highlights the significant environmental impacts of a particular municipal engineering project prior to the construction stage. Consequently, preventive actions can be planned and implemented during on-site activities. The results of the model also allow a comparison of proposed municipal engineering projects and alternatives with respect to the overall on-site environmental impact and the absolute importance of a particular environmental aspect. These findings are useful within the framework of the environmental impact assessment process, as they help to improve the identification and evaluation of on-site environmental aspects of municipal engineering works. The findings may also be of use to construction companies that are willing to implement an environmental management system or simply wish to improve on-site environmental performance in municipal engineering projects. -- Highlights: • We present a model to predict the environmental impacts of municipal engineering works. • It highlights significant on-site environmental impacts prior to the construction stage. • Findings are useful within the environmental impact assessment process. • They also help contractors to implement environmental management systems.« less

Ferrographic and spectrographic analysis of oil sampled before and after failure of a jet engine

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.

1980-01-01

An experimental gas turbine engine was destroyed as a result of the combustion of its titanium components. Several engine oil samples (before and after the failure) were analyzed with a Ferrograph as well as plasma, atomic absorption, and emission spectrometers. The analyses indicated that a lubrication system failure was not a causative factor in the engine failure. Neither an abnormal wear mechanism, nor a high level of wear debris was detected in the oil sample from the engine just prior to the test in which the failure occurred. However, low concentrations of titanium were evident in this sample and samples taken earlier. After the failure, higher titanium concentrations were detected in oil samples taken from different engine locations. Ferrographic analysis indicated that most of the titanium was contained in spherical metallic debris after the failure.

40 CFR 92.129 - Exhaust sample analysis.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the span drift between the pre-analysis and post-analysis checks on any range used may exceed 3...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.129 Exhaust sample... and span each range to be used on each analyzer used prior to the beginning of the test sequence. The...

40 CFR 92.129 - Exhaust sample analysis.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the span drift between the pre-analysis and post-analysis checks on any range used may exceed 3... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.129 Exhaust... and span each range to be used on each analyzer used prior to the beginning of the test sequence. The...

40 CFR 92.129 - Exhaust sample analysis.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the span drift between the pre-analysis and post-analysis checks on any range used may exceed 3... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.129 Exhaust... and span each range to be used on each analyzer used prior to the beginning of the test sequence. The...

40 CFR 92.129 - Exhaust sample analysis.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the span drift between the pre-analysis and post-analysis checks on any range used may exceed 3... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.129 Exhaust... and span each range to be used on each analyzer used prior to the beginning of the test sequence. The...

40 CFR 92.129 - Exhaust sample analysis.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the span drift between the pre-analysis and post-analysis checks on any range used may exceed 3... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.129 Exhaust... and span each range to be used on each analyzer used prior to the beginning of the test sequence. The...

Relationship of prior knowledge and working engineers' learning preferences: implications for designing effective instruction

NASA Astrophysics Data System (ADS)

Baukal, Charles E.; Ausburn, Lynna J.

2017-05-01

Continuing engineering education (CEE) is important to ensure engineers maintain proficiency over the life of their careers. However, relatively few studies have examined designing effective training for working engineers. Research has indicated that both learner instructional preferences and prior knowledge can impact the learning process, but it has not established if these factors are interrelated. The study reported here considered relationships of prior knowledge and three aspects of learning preferences of working engineers at a manufacturing company: learning strategy choices, verbal-visual cognitive styles, and multimedia preferences. Prior knowledge was not found to be significantly related to engineers' learning preferences, indicating independence of effects of these variables on learning. The study also examined relationships of this finding to the Multimedia Cone of Abstraction and implications for its use as an instructional design tool for CEE.

Modulation of high frequency noise by engine tones of small boats.

PubMed

Pollara, Alexander; Sutin, Alexander; Salloum, Hady

2017-07-01

The effect of modulation of high frequency ship noise by propeller rotation frequencies is well known. This modulation is observed with the Detection of Envelope Modulation on Noise (DEMON) algorithm. Analysis of the DEMON spectrum allows the revolutions per minute and number of blades of the propeller to be determined. This work shows that the high frequency noise of a small boat can also be modulated by engine frequencies. Prior studies have not reported high frequency noise amplitude modulated at engine frequencies. This modulation is likely produced by bubbles from the engine exhaust system.

Aircraft Maintenance Engineering: Factors Impacting Airlines E-Maintenance Technologies, Authoring and Illustrations

NASA Astrophysics Data System (ADS)

Karayianes, Frank

The purpose of this research was to evaluate factors influencing acceptance and use of technologies in the field of aircraft maintenance authoring, graphics, and documentation. Maintenance engineering authors convert complex engineering used in aircraft production and transform that data using technology (tools) into usable technical publications data. While the current literature includes a large volume of research in technology acceptance in various domains of industry and business, the problem is that no such studies exist with respect to the aircraft maintenance engineering authoring, allowing any number of tools to be used and acceptance to be unsure. The study was based on theoretical approaches of the Technology Acceptance Model and the associated hypothesis related to eight research questions. A survey questionnaire was developed for data collection from a selected population of aircraft maintenance engineering authors. Data collected from 148 responses were exposed to a range of statistical methods and analyses. Analysis of data were performed within the structural equation model using exploratory factor analysis, confirmatory factor analysis, and a range of regression methods. The analyses generally provided results consistent with prior literature. Two survey questions yielded unexpected results contrary to similar studies. The relationship between prior experience and job level did not show a significant relationship with perceived usefulness or perceived ease of use. Other results included the significant relationship between Perceived Usefulness and Perceived Ease of Use with Technology acceptance. Recommendations include understanding how Technology Acceptance can be improved for the industry and the need for further research not covered to refine recommendations for technology acceptance related to the aviation industry.

Relationship of Prior Knowledge and Working Engineers' Learning Preferences: Implications for Designing Effective Instruction

ERIC Educational Resources Information Center

Baukal, Charles E.; Ausburn, Lynna J.

2017-01-01

Continuing engineering education (CEE) is important to ensure engineers maintain proficiency over the life of their careers. However, relatively few studies have examined designing effective training for working engineers. Research has indicated that both learner instructional preferences and prior knowledge can impact the learning process, but it…

A mathematical model to describe the nonlinear elastic properties of the gastrocnemius tendon of chickens.

PubMed

Foutz, T L

1991-03-01

A phenomenological model was developed to describe the nonlinear elastic behavior of the avian gastrocnemius tendon. Quasistatic uniaxial tensile tests were used to apply a deformation and resulting load on the tendon at a deformation rate of 5 mm/min. Plots of deformation versus load indicated a nonlinear loading response. By calculating engineering stress and engineering strain, the experimental data were normalized for tendon shape. The elastic response was determined from stress-strain curves and was found to vary with engineering strain. The response to the applied engineering strain could best be described by a mathematical model that combined a linear function and a nonlinear function. Three parameters in the model were developed to represent the nonlinear elastic behavior of the tendon, thereby allowing analysis of elasticity without prior knowledge of engineering strain. This procedure reduced the amount of data needed for the statistical analysis of nonlinear elasticity.

Multiobjective Decision Analysis With Engineering and Business Applications

NASA Astrophysics Data System (ADS)

Wood, Eric

The last 15 years have witnessed the development of a large number of multiobjective decision techniques. Applying these techniques to environmental, engineering, and business problems has become well accepted. Multiobjective Decision Analysis With Engineering and Business Applications attempts to cover the main multiobjective techniques both in their mathematical treatment and in their application to real-world problems.The book is divided into 12 chapters plus three appendices. The main portion of the book is represented by chapters 3-6, Where the various approaches are identified, classified, and reviewed. Chapter 3 covers methods for generating nondominated solutions; chapter 4, continuous methods with prior preference articulation; chapter 5, discrete methods with prior preference articulation; and chapter 6, methods of progressive articulation of preferences. In these four chapters, close to 20 techniques are discussed with over 20 illustrative examples. This is both a strength and a weakness; the breadth of techniques and examples provide comprehensive coverage, but it is in a style too mathematically compact for most readers. By my count, the presentation of the 20 techniques in chapters 3-6 covered 85 pages, an average of about 4.5 pages each; therefore, a sound basis in linear algebra and linear programing is required if the reader hopes to follow the material. Chapter 2, “Concepts in Multiobjective Analysis,” also assumes such a background.

Providing Nuclear Criticality Safety Analysis Education through Benchmark Experiment Evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

John D. Bess; J. Blair Briggs; David W. Nigg

2009-11-01

One of the challenges that today's new workforce of nuclear criticality safety engineers face is the opportunity to provide assessment of nuclear systems and establish safety guidelines without having received significant experience or hands-on training prior to graduation. Participation in the International Criticality Safety Benchmark Evaluation Project (ICSBEP) and/or the International Reactor Physics Experiment Evaluation Project (IRPhEP) provides students and young professionals the opportunity to gain experience and enhance critical engineering skills.

40 CFR 610.11 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... (17) “Data fleet” means a fleet of automobiles tested at “zero device-miles” in “baseline.... (19) “Zero device-miles” means the period of time between retrofit installation and the accumulation...” means the engineering analysis performed by EPA prior to testing prescribed by the Administrator based...

Ferrographic and spectrometer oil analysis from a failed gas turbine engine

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.

1982-01-01

An experimental gas turbine engine was destroyed as a result of the combustion of its titanium components. It was concluded that a severe surge may have caused interference between rotating and stationary compressor that either directly or indirectly ignited the titanium components. Several engine oil samples (before and after the failure) were analyzed with a Ferrograph, a plasma, an atomic absorption, and an emission spectrometer to see if this information would aid in the engine failure diagnosis. The analyses indicated that a lubrication system failure was not a causative factor in the engine failure. Neither an abnormal wear mechanism nor a high level of wear debris was detected in the engine oil sample taken just prior to the test in which the failure occurred. However, low concentrations (0.2 to 0.5 ppm) of titanium were evident in this sample and samples taken earlier. After the failure, higher titanium concentrations ( 2 ppm) were detected in oil samples taken from different engine locations. Ferrographic analysis indicated that most of the titanium was contained in spherical metallic debris after the failure. The oil analyses eliminated a lubrication system bearing or shaft seal failure as the cause of the engine failure.

T55 power turbine rotor multiplane-multispeed balancing study

NASA Technical Reports Server (NTRS)

Martin, M. R.

1982-01-01

A rotordynamic analysis of the T55-L-11C engine was used to evaluate the balancing needs of the power turbine and to optimize the balancing procedure. As a result, recommendations were made for implementation of a multiplane-multispeed balancing plan. Precision collars for the attachment of trial weights to a slender rotor were designed enabling demonstration balancing on production hardware. The quality of the balance was then evaluated by installing a high speed balanced power turbine in an engine and running in a test cell at the Corpus Christi Army depot. The engine used had been tested prior to the turbine changeout and showed acceptable overall vibration levels for the engine were significantly reduced, demonstrating the ability of multiplane-multispeed balancing to control engine vibration.

34 CFR 82.300 - Professional and technical services.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false Professional and technical services. 82.300 Section 82.300 Education Office of the Secretary, Department of Education NEW RESTRICTIONS ON LOBBYING Activities... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

34 CFR 82.205 - Professional and technical services.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false Professional and technical services. 82.205 Section 82.205 Education Office of the Secretary, Department of Education NEW RESTRICTIONS ON LOBBYING Activities... providing an engineering analysis prior to the preparation or submission of a bid or proposal are not...

The Power Prior: Theory and Applications

PubMed Central

Ibrahim, Joseph G.; Chen, Ming-Hui; Gwon, Yeongjin; Chen, Fang

2015-01-01

The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. It has also been applied for a wide variety of models and settings, both in the experimental design and analysis contexts. In this review article, we give an A to Z exposition of the power prior and its applications to date. We review its theoretical properties, variations in its formulation, statistical contexts for which it has been used, applications, and its advantages over other informative priors. We review models for which it has been used, including generalized linear models, survival models, and random effects models. Statistical areas where the power prior has been used include model selection, experimental design, hierarchical modeling, and conjugate priors. Prequentist properties of power priors in posterior inference are established and a simulation study is conducted to further examine the empirical performance of the posterior estimates with power priors. Real data analyses are given illustrating the power prior as well as the use of the power prior in the Bayesian design of clinical trials. PMID:26346180

Numerical Zooming Between a NPSS Engine System Simulation and a One-Dimensional High Compressor Analysis Code

NASA Technical Reports Server (NTRS)

Follen, Gregory; auBuchon, M.

2000-01-01

Within NASA's High Performance Computing and Communication (HPCC) program, NASA Glenn Research Center is developing an environment for the analysis/design of aircraft engines called the Numerical Propulsion System Simulation (NPSS). NPSS focuses on the integration of multiple disciplines such as aerodynamics, structures, and heat transfer along with the concept of numerical zooming between zero-dimensional to one-, two-, and three-dimensional component engine codes. In addition, the NPSS is refining the computing and communication technologies necessary to capture complex physical processes in a timely and cost-effective manner. The vision for NPSS is to create a "numerical test cell" enabling full engine simulations overnight on cost-effective computing platforms. Of the different technology areas that contribute to the development of the NPSS Environment, the subject of this paper is a discussion on numerical zooming between a NPSS engine simulation and higher fidelity representations of the engine components (fan, compressor, burner, turbines, etc.). What follows is a description of successfully zooming one-dimensional (row-by-row) high-pressure compressor analysis results back to a zero-dimensional NPSS engine simulation and a discussion of the results illustrated using an advanced data visualization tool. This type of high fidelity system-level analysis, made possible by the zooming capability of the NPSS, will greatly improve the capability of the engine system simulation and increase the level of virtual test conducted prior to committing the design to hardware.

Thermal Analysis of Cryogenic Hydrogen Liquid Separator

NASA Technical Reports Server (NTRS)

Congiardo, Jared F.; Fortier, Craig R. (Editor)

2014-01-01

During launch for the new Space Launch System (SLS) liquid hydrogen is bleed through the engines during replenish, pre-press, and extended pre-press to condition the engines prior to launch. The predicted bleed flow rates are larger than for the shuttle program. A consequence of the increased flow rates is having liquif hydrogen in the vent system, which the facilities was never designed to handle. To remedy the problem a liquid separator is being designed in the system to accumulated the liquid propellant and protect the facility flare stack (which can only handle gas). The attached document is a presentation of the current thermalfluid analysis performed for the separator and will be presented at the Thermal and Fluid Analysis Workshop (NASA workshop) next week in Cleveland, Ohio.

High School Graphics Experience Influencing the Self-Efficacy of First-Year Engineering Students in an Introductory Engineering Graphics Course

ERIC Educational Resources Information Center

Metraglia, Riccardo; Villa, Valerio; Baronio, Gabriele; Adamini, Riccardo

2015-01-01

Today's students enter engineering colleges with different technical backgrounds and prior graphics experience. This may due to their high school of provenience, which can be technical or non-technical. The prior experience affects students' ability in learning and hence their motivation and self-efficacy beliefs. This study intended to evaluate…

SSC Engineering Analysis

NASA Technical Reports Server (NTRS)

Ryan, Harry; Junell, Justin; Albasini, Colby; O'Rourke, William; Le, Thang; Strain, Ted; Stiglets, Tim

2011-01-01

A package for the automation of the Engineering Analysis (EA) process at the Stennis Space Center has been customized. It provides the ability to assign and track analysis tasks electronically, and electronically route a task for approval. It now provides a mechanism to keep these analyses under configuration management. It also allows the analysis to be stored and linked to the engineering data that is needed to perform the analysis (drawings, etc.). PTC s (Parametric Technology Corp o ration) Windchill product was customized to allow the EA to be created, routed, and maintained under configuration management. Using Infoengine Tasks, JSP (JavaServer Pages), Javascript, a user interface was created within the Windchill product that allows users to create EAs. Not only does this interface allow users to create and track EAs, but it plugs directly into the out-ofthe- box ability to associate these analyses with other relevant engineering data such as drawings. Also, using the Windchill workflow tool, the Design and Data Management System (DDMS) team created an electronic routing process based on the manual/informal approval process. The team also added the ability for users to notify and track notifications to individuals about the EA. Prior to the Engineering Analysis creation, there was no electronic way of creating and tracking these analyses. There was also a feature that was added that would allow users to track/log e-mail notifications of the EA.

Methodology discourses as boundary work in the construction of engineering education.

PubMed

Beddoes, Kacey

2014-04-01

Engineering education research is a new field that emerged in the social sciences over the past 10 years. This analysis of engineering education research demonstrates that methodology discourses have played a central role in the construction and development of the field of engineering education, and that they have done so primarily through boundary work. This article thus contributes to science and technology studies literature by examining the role of methodology discourses in an emerging social science field. I begin with an overview of engineering education research before situating the case within relevant bodies of literature on methodology discourses and boundary work. I then identify two methodology discourses--rigor and methodological diversity--and discuss how they contribute to the construction and development of engineering education research. The article concludes with a discussion of how the findings relate to prior research on methodology discourses and boundary work and implications for future research.

Gender and Teamwork: An Analysis of Professors' Perspectives and Practices

ERIC Educational Resources Information Center

Beddoes, Kacey; Panther, Grace

2018-01-01

Teamwork is increasingly seen as an important component of engineering education programmes. Yet, prior research has shown that there are numerous ways in which teamwork is gendered, and can lead to negative experiences for women students. This article presents the first interview findings on professors' perspectives on gender and teamwork.…

Gender and teamwork: an analysis of professors' perspectives and practices

NASA Astrophysics Data System (ADS)

Beddoes, Kacey; Panther, Grace

2018-05-01

Teamwork is increasingly seen as an important component of engineering education programmes. Yet, prior research has shown that there are numerous ways in which teamwork is gendered, and can lead to negative experiences for women students. This article presents the first interview findings on professors' perspectives on gender and teamwork. Semi-structured interviews were conducted with 39 engineering professors to determine what and how they thought about gender in engineering and engineering education. For this article, the parts of the interviews about teamwork are analysed. We conclude that professors need tools to help them facilitate gender-inclusive teamwork, and those tools must address the beliefs that they already hold about teamwork. The findings raise questions about the adoption of evidence-based instructional practices and suggest current teamwork practices may exacerbate gender inequalities in engineering.

Is Mars Sample Return Required Prior to Sending Humans to Mars?

NASA Technical Reports Server (NTRS)

Carr, Michael; Abell, Paul; Allwood, Abigail; Baker, John; Barnes, Jeff; Bass, Deborah; Beaty, David; Boston, Penny; Brinkerhoff, Will; Budney, Charles;

First-year engineering students' views of the nature of engineering: implications for engineering programmes

NASA Astrophysics Data System (ADS)

Karataş, F. Ö.; Bodner, G. M.; Unal, Suat

2016-01-01

A study was conducted on the views of the nature of engineering held by 114 first-year engineering majors; the study built on prior work on views of the nature of science held by students, their instructors, and the general public. Open-coding analysis of responses to a 12-item questionnaire suggested that the participants held tacit beliefs that engineering (1) involves problem solving; (2) is a form of applied science; (3) involves the design of artefacts or systems; (4) is subject to various constraints; and (5) requires teamwork. These beliefs, however, were often unsophisticated, and significant aspects of the field of engineering as described in the literature on engineering practices were missing from the student responses. The results of this study are important because students' beliefs have a strong influence on what they value in a classroom situation, what they attend to in class, and how they choose to study for a course.

SACD's Support of the Hyper-X Program

NASA Technical Reports Server (NTRS)

Robinson, Jeffrey S.; Martin, John G.

2006-01-01

NASA s highly successful Hyper-X program demonstrated numerous hypersonic air-breathing vehicle related technologies including scramjet performance, advanced materials and hot structures, GN&C, and integrated vehicle performance resulting in, for the first time ever, acceleration of a vehicle powered by a scramjet engine. The Systems Analysis and Concepts Directorate (SACD) at NASA s Langley Research Center played a major role in the integrated team providing critical support, analysis, and leadership to the Hyper-X Program throughout the program s entire life and were key to its ultimate success. Engineers in SACD s Vehicle Analysis Branch (VAB) were involved in all stages and aspects of the program, from conceptual design prior to contract award, through preliminary design and hardware development, and in to, during, and after each of the three flights. Working closely with other engineers at Langley and Dryden, as well as industry partners, roughly 20 members of SACD were involved throughout the evolution of the Hyper-X program in nearly all disciplines, including lead roles in several areas. Engineers from VAB led the aerodynamic database development, the propulsion database development, and the stage separation analysis and database development effort. Others played major roles in structures, aerothermal, GN&C, trajectory analysis and flight simulation, as well as providing CFD support for aerodynamic, propulsion, and aerothermal analysis.

The power prior: theory and applications.

PubMed

Ibrahim, Joseph G; Chen, Ming-Hui; Gwon, Yeongjin; Chen, Fang

2015-12-10

The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. It has also been applied for a wide variety of models and settings, both in the experimental design and analysis contexts. In this review article, we give an A-to-Z exposition of the power prior and its applications to date. We review its theoretical properties, variations in its formulation, statistical contexts for which it has been used, applications, and its advantages over other informative priors. We review models for which it has been used, including generalized linear models, survival models, and random effects models. Statistical areas where the power prior has been used include model selection, experimental design, hierarchical modeling, and conjugate priors. Frequentist properties of power priors in posterior inference are established, and a simulation study is conducted to further examine the empirical performance of the posterior estimates with power priors. Real data analyses are given illustrating the power prior as well as the use of the power prior in the Bayesian design of clinical trials. Copyright © 2015 John Wiley & Sons, Ltd.

Ferrographic and spectrometer oil analysis from a failed gas turbine engine

NASA Technical Reports Server (NTRS)

Jones, W. R., Jr.

1983-01-01

An experimental gas turbine engine was destroyed as a result of the combustion of its titanium components. It was concluded that a severe surge may have caused interference between rotating and stationary compressor parts that either directly or indirectly ignited the titanium components. Several engine oil samples (before and after the failure) were analyzed with a Ferrograph, and with plasma, atomic absorption, and emission spectrometers to see if this information would aid in the engine failure diagnosis. The analyses indicated that a lubrication system failure was not a causative factor in the engine failure. Neither an abnormal wear mechanism nor a high level of wear debris was detected in the engine oil sample taken just prior to the test in which the failure occurred. However, low concentrations (0.2 to 0.5 ppm) of titanium were evident in this sample and samples taken earlier. After the failure, higher titanium concentrations (2 ppm) were detected in oil samples taken from different engine locations. Ferrographic analysis indicated that most of the titanium was contained in spherical metallic debris after the failure. The oil analyses eliminated a lubrication system bearing or shaft seal failure as the cause of the engine failure. Previously announced in STAR as N83-12433

An Assessment of the Effectiveness of Air Force Risk Management Practices in Program Acquisition Using Survey Instrument Analysis

DTIC Science & Technology

2015-06-18

Engineering Effectiveness Survey. CMU/SEI-2012-SR-009. Carnegie Mellon University. November 2012. Field, Andy. Discovering Statistics Using SPSS , 3rd...enough into the survey to begin answering questions on risk practices. All of the data statistical analysis will be performed using SPSS . Prior to...probabilistically using distributions for likelihood and impact. Statistical methods like Monte Carlo can more comprehensively evaluate the cost and

Not so global: a bibliometric look at engineering education research

NASA Astrophysics Data System (ADS)

Williams, Bill; Wankat, Phillip C.; Neto, Pedro

2018-03-01

It has been suggested that Engineering Education Research (EER) is going global. If this were the case we would assume that the research of EER scholars in different parts of the globe would be informed by literature describing prior work within and beyond their home country/region. The authors set out to test this hypothesis by applying citation analysis to research presented in four publication venues: the annual conferences organised by ASEE (American Society of Engineering Education) and SEFI (European Society of Engineering Education) and two archival journals published by these two societies: Journal of Engineering Education (JEE) and European Journal of Engineering Education (EJEE). Our findings from the analysis of 4321 publications show that citations in ASEE conferences are dominated by sources with US affiliations, whereas the SEFI data show that while US sources are frequently cited, European and other authors are also well represented. With regard to the journals JEE and EJEE, a similar pattern is observed. These results suggest that, in citation terms, European EER is relatively global but US EER is not. The authors conclude by suggesting that if the EER community is to aspire to quality scholarship, there needs to be debate around how such issues can be tackled.

Advanced Single-Aisle Transport Propulsion Design Options Revisited

NASA Technical Reports Server (NTRS)

Guynn, Mark D.; Berton, Jeffrey J.; Tong, Michael T.; Haller, William J.

2013-01-01

Future propulsion options for advanced single-aisle transports have been investigated in a number of previous studies by the authors. These studies have examined the system level characteristics of aircraft incorporating ultra-high bypass ratio (UHB) turbofans (direct drive and geared) and open rotor engines. During the course of these prior studies, a number of potential refinements and enhancements to the analysis methodology and assumptions were identified. This paper revisits a previously conducted UHB turbofan fan pressure ratio trade study using updated analysis methodology and assumptions. The changes incorporated have decreased the optimum fan pressure ratio for minimum fuel consumption and reduced the engine design trade-offs between minimizing noise and minimizing fuel consumption. Nacelle drag and engine weight are found to be key drivers in determining the optimum fan pressure ratio from a fuel efficiency perspective. The revised noise analysis results in the study aircraft being 2 to 4 EPNdB (cumulative) quieter due to a variety of reasons explained in the paper. With equal core technology assumed, the geared engine architecture is found to be as good as or better than the direct drive architecture for most parameters investigated. However, the engine ultimately selected for a future advanced single-aisle aircraft will depend on factors beyond those considered here.

STS-114: Engine Cut-Off Sensors Are a No-Go: Teaching Notes for NASA Case Study

NASA Technical Reports Server (NTRS)

Ransom, Khadijah S.; Johnson, Grace K.

2013-01-01

This case study format is intended to simulate the experience of facing the same difficult challenges and making the same critical decisions as managers, engineers, and scientists in the Space Shuttle Program. It has been designed for use in the classroom setting to help students develop skills related to decision-making. Students will read about the engine cut-off sensor anomaly which created challenges during the STS-114 mission and have the opportunity to make decisions as lead NASA engineers and Mission Management Team members. Included within this document are three case study presentation options - class discussion, group activity, and open-ended research. Please read the full case prior to in-class presentation to allow ample time for students' analysis and reflection, as well as to prepare additional questions. activities or exercises, material selection, etc. Depending upon the setting of your presentation and the number of participants, please choose at least one presentation format beforehand and plan accordingly. You may expect the following learning objectives by using the proposed formats. Learning Objectives: To enable students to experience the responsibilities of NASA management, engineers, and analysis; to discover possible procedures for investigating system anomalies; to become familiar with the liquid hydrogen low level engine cut-off sensor, including its function, connecting components, and location within the Space Shuttle; and to encourage critical analysis and stimulating discussion of Space Shuttle mission challenges.

Determination of Shed Ice Particle Size Using High Speed Digital Imaging

NASA Technical Reports Server (NTRS)

Broughton, Howard; Owens, Jay; Sims, James J.; Bond, Thomas H.

1996-01-01

A full scale model of an aircraft engine inlet was tested at NASA Lewis Research Center's Icing Research Tunnel. Simulated natural ice sheds from the engine inlet lip were studied using high speed digital image acquisition and image analysis. Strategic camera placement integrated at the model design phase allowed the study of ice accretion on the inlet lip and the resulting shed ice particles at the aerodynamic interface plane at the rear of the inlet prior to engine ingestion. The resulting digital images were analyzed using commercial and proprietary software to determine the size of the ice particles that could potentially be ingested by the engine during a natural shedding event. A methodology was developed to calibrate the imaging system and insure consistent and accurate measurements of the ice particles for a wide range of icing conditions.

The JT9D Jet Engine Diagnostics Program

NASA Technical Reports Server (NTRS)

Olsson, W. J.

1982-01-01

The various engine deterioration phenomena that affect JT9D performance retention were studied, and approaches to improve performance retention of engines were identified. The program included surveys of historical data, monitoring of in service engines, ground and flight testing of instrumented engines, analysis, and analytical modeling. Performance deterioration is made up of both short and long term modes, both of which are flight cycle related phenomena. Short term deterioration occurs primarily during airplane acceptance testing prior to delivery to the airline. This effect is caused by flight load and power induced clearance closures and engine deflections with resulting rubbing of airfoils and seals. Long term deterioration is caused by erosion of airfoils and gas path seals during ground operation and take off and by cyclic induced thermal distortion of the high pressure turbine airfoils. Studies of possible remedial approaches have shown that performance retention within 1 to 2 percent of initial revenue service performance can be achieved with a proper program of hot section and cold section maintenance.

Concept Development and Meaningful Learning among Electrical Engineering Students Engaged in a Problem-Based Laboratory Experience

ERIC Educational Resources Information Center

Bledsoe, Karen E.; Flick, Lawrence

2012-01-01

This phenomenographic study documented changes in student-held electrical concepts the development of meaningful learning among students with both low and high prior knowledge within a problem-based learning (PBL) undergraduate electrical engineering course. This paper reports on four subjects: two with high prior knowledge and two with low prior…

Cost/Effort Drivers and Decision Analysis

NASA Technical Reports Server (NTRS)

Seidel, Jonathan

2010-01-01

Engineering trade study analyses demand consideration of performance, cost and schedule impacts across the spectrum of alternative concepts and in direct reference to product requirements. Prior to detailed design, requirements are too often ill-defined (only goals ) and prone to creep, extending well beyond the Systems Requirements Review. Though lack of engineering design and definitive requirements inhibit the ability to perform detailed cost analyses, affordability trades still comprise the foundation of these future product decisions and must evolve in concert. This presentation excerpts results of the recent NASA subsonic Engine Concept Study for an Advanced Single Aisle Transport to demonstrate an affordability evaluation of performance characteristics and the subsequent impacts on engine architecture decisions. Applying the Process Based Economic Analysis Tool (PBEAT), development cost, production cost, as well as operation and support costs were considered in a traditional weighted ranking of the following system-level figures of merit: mission fuel burn, take-off noise, NOx emissions, and cruise speed. Weighting factors were varied to ascertain the architecture ranking sensitivities to these performance figures of merit with companion cost considerations. A more detailed examination of supersonic variable cycle engine cost is also briefly presented, with observations and recommendations for further refinements.

40 CFR 1065.518 - Engine preconditioning.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Engine preconditioning. 1065.518... CONTROLS ENGINE-TESTING PROCEDURES Performing an Emission Test Over Specified Duty Cycles § 1065.518 Engine preconditioning. (a) This section applies for engines where measured emissions are affected by prior operation...

CO2 Radiocarbon Analysis to Quantify Organic Contaminant Degradation, MNA, and Engineered Remediation Approaches

DTIC Science & Technology

2014-12-18

carbon backbone). This may be analytically relevant where soil gas is sampled under anaerobic conditions. However, at the soil:air interface, methane is...of the ambient CO2 on-site coming from the fossil end-member (i.e. the contaminant). Sampling , processing and analysis of soil gas 14CO2 and 14CH4...gasoline service station having fuel-contaminated soil and groundwater. The SVE system ran for ~3 months prior to sampling . Soil gas and groundwater

A 3-Component Mixture of Rayleigh Distributions: Properties and Estimation in Bayesian Framework

PubMed Central

Aslam, Muhammad; Tahir, Muhammad; Hussain, Zawar; Al-Zahrani, Bander

2015-01-01

To study lifetimes of certain engineering processes, a lifetime model which can accommodate the nature of such processes is desired. The mixture models of underlying lifetime distributions are intuitively more appropriate and appealing to model the heterogeneous nature of process as compared to simple models. This paper is about studying a 3-component mixture of the Rayleigh distributionsin Bayesian perspective. The censored sampling environment is considered due to its popularity in reliability theory and survival analysis. The expressions for the Bayes estimators and their posterior risks are derived under different scenarios. In case the case that no or little prior information is available, elicitation of hyperparameters is given. To examine, numerically, the performance of the Bayes estimators using non-informative and informative priors under different loss functions, we have simulated their statistical properties for different sample sizes and test termination times. In addition, to highlight the practical significance, an illustrative example based on a real-life engineering data is also given. PMID:25993475

Environmental Engineering in Mining Engineering Education

ERIC Educational Resources Information Center

Mahamud-Lopez, Manuel Maria; Menendez-Aguado, Juan Maria

2005-01-01

In this paper, the current profile of the environmental engineer and the programming of the subject "Environmental Engineering and Technology" corresponding to the studies of Mining Engineering at the University of Oviedo in Spain, is discussed. Professional profile, student knowledge prior to and following instruction as well as…

Long-term CF6 engine performance deterioration: Evaluation of engine S/N 451-479

NASA Technical Reports Server (NTRS)

Kramer, W. H.; Smith, J. J.

1978-01-01

The performance testing and analytical teardown of CF6-6D engine is summarized. This engine had completed its initial installation on DC-10 aircraft. The investigative test program was conducted inbound prior to normal overhaul/refurbishment. The performance testing included an inbound test, a test following cleaning of the low pressure turbine airfoils, and a final test after leading edge rework and cleaning the stage one fan blades. The analytical teardown consisted of detailed disassembly inspection measurements and airfoil surface finish checks of the as received deteriorated hardware. Included in this report is a detailed analysis of the test cell performance data, a complete analytical teardown report with a detailed description of all observed hardware distress, and an analytical assessment of the performance loss (deterioration) relating measured hardware conditions to losses in both SFC (specific fuel consumption) and EGT (exhaust gas temperature).

40 CFR 92.508 - Calculation and reporting of test results.

Code of Federal Regulations, 2010 CFR

2010-07-01

... specified in § 92.506(a). These results must also include the green engine factor, if applicable. The... engine, including: (A) Configuration and engine family identification; (B) Year, make, and build date; (C... accumulated on locomotive or locomotive engine prior to testing; and (E) Description of green engine factor...

40 CFR 92.1107 - Warranty provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... with locomotives or locomotive engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES General Enforcement Provisions and... locomotive engine must warrant to the ultimate purchaser and each subsequent purchaser or owner that the...

40 CFR 94.1107 - Warranty provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... were in general use with engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Enforcement Provisions and Prohibited Acts § 94.1107 Warranty provisions. (a) The manufacturer of each engine must warrant to the...

40 CFR 92.1107 - Warranty provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... with locomotives or locomotive engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES General Enforcement Provisions and... locomotive engine must warrant to the ultimate purchaser and each subsequent purchaser or owner that the...

40 CFR 94.1107 - Warranty provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... were in general use with engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Enforcement Provisions and Prohibited Acts § 94.1107 Warranty provisions. (a) The manufacturer of each engine must warrant to the...

40 CFR 94.1107 - Warranty provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... were in general use with engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Enforcement Provisions and Prohibited Acts § 94.1107 Warranty provisions. (a) The manufacturer of each engine must warrant to the...

40 CFR 92.1107 - Warranty provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... with locomotives or locomotive engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES General Enforcement Provisions and... locomotive engine must warrant to the ultimate purchaser and each subsequent purchaser or owner that the...

40 CFR 94.1107 - Warranty provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... were in general use with engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Enforcement Provisions and Prohibited Acts § 94.1107 Warranty provisions. (a) The manufacturer of each engine must warrant to the...

40 CFR 94.1107 - Warranty provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... were in general use with engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Enforcement Provisions and Prohibited Acts § 94.1107 Warranty provisions. (a) The manufacturer of each engine must warrant to the...

40 CFR 92.1107 - Warranty provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... with locomotives or locomotive engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES General Enforcement Provisions and... locomotive engine must warrant to the ultimate purchaser and each subsequent purchaser or owner that the...

40 CFR 92.1107 - Warranty provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... with locomotives or locomotive engines prior to 1999. For diesel engines, this would generally include...) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES General Enforcement Provisions and... locomotive engine must warrant to the ultimate purchaser and each subsequent purchaser or owner that the...

Spring 2013 Graduate Engineering Internship Summary

NASA Technical Reports Server (NTRS)

Ehrlich, Joshua

2013-01-01

In the spring of 2013, I participated in the National Aeronautics and Space Administration (NASA) Pathways Intern Employment Program at the Kennedy Space Center (KSC) in Florida. This was my final internship opportunity with NASA, a third consecutive extension from a summer 2012 internship. Since the start of my tenure here at KSC, I have gained an invaluable depth of engineering knowledge and extensive hands-on experience. These opportunities have granted me the ability to enhance my systems engineering approach in the field of payload design and testing as well as develop a strong foundation in the area of composite fabrication and testing for repair design on space vehicle structures. As a systems engineer, I supported the systems engineering and integration team with final acceptance testing of the Vegetable Production System, commonly referred to as Veggie. Verification and validation (V and V) of Veggie was carried out prior to qualification testing of the payload, which incorporated the process of confirming the system's design requirements dependent on one or more validation methods: inspection, analysis, demonstration, and testing.

Spring 2014 Internship Diffuser Data Analysis

NASA Technical Reports Server (NTRS)

Laigaie, Robert T.; Ryan, Harry M.

2014-01-01

J-2X engine testing on the A-2 test stand at the NASA John C. Stennis Space Center (SSC) has recently concluded. As part of that test campaign, the engine was operated at lower power levels in support of expanding the use of J-2X to other missions. However, the A-2 diffuser was not designed for engine testing at the proposed low power levels. To evaluate the risk of damage to the diffuser, computer simulations were created of the rocket engine exhaust plume inside the 50ft long, water-cooled, altitude-simulating diffuser. The simulations predicted that low power level testing would cause the plume to oscillate in the lower sections of the diffuser. This can possibly cause excessive vibrations, stress, and heat transfer from the plume to the diffuser walls. To understand and assess the performance of the diffuser during low power level engine testing, nine accelerometers and four strain gages were installed around the outer surface of the diffuser. The added instrumentation also allowed for the verification of the rocket exhaust plume computational model. Prior to engine hot-fire testing, a diffuser water-flow test was conducted to verify the proper operation of the newly installed instrumentation. Subsequently, two J-2X engine hot-fire tests were completed. Hot-Fire Test 1 was 11.5 seconds in duration, and accelerometer and strain data verified that the rocket engine plume oscillated in the lower sections of the diffuser. The accelerometers showed very different results dependent upon location. The diffuser consists of four sections, with Section 1 being closest to the engine nozzle and Section 4 being farthest from the engine nozzle. Section 1 accelerometers showed increased amplitudes at startup and shutdown, but low amplitudes while the diffuser was started. Section 3 accelerometers showed the opposite results with near zero G amplitudes prior to and after diffuser start and peak amplitudes to +/- 100G while the diffuser was started. Hot-Fire Test 1 strain gages showed different data dependent on section. Section 1 strains were small, and were in the range of 50 to 150 microstrain, which would result in stresses from 1.45 to 4.35 ksi. The yield stress of the material, A-285 Grade C Steel, is 29.7 ksi. Section 4 strain gages showed much higher values with strains peaking at 1600 microstrain. This strain corresponds to a stress of 46.41 ksi, which is in excess of the yield stress, but below the ultimate stress of 55 to 75 ksi. The decreased accelerations and strain in Section 1, and the increased accelerations and strain in Sections 3 and 4 verified the computer simulation prediction of increased plume oscillations in the lower sections of the diffuser. Hot-Fire Test 2 ran for a duration of 125 seconds. The engine operated at a slightly higher power level than Hot-Fire Test 1 for the initial 35 seconds of the test. After 35 seconds the power level was lowered to Hot-Fire Test 1 levels. The acceleration and strain data for Hot-Fire Test 2 was similar during the initial part of the test. However, just prior to the engine being lowered to the Hot-Fire Test 1 power level, the strain gage data in Section 4 showed a large decrease to strains near zero microstrain from their peak at 1500 microstrain. Future work includes further strain and acceleration data analysis and evaluation.

Development of the Functional Flow Block Diagram for the J-2X Rocket Engine System

NASA Technical Reports Server (NTRS)

White, Thomas; Stoller, Sandra L.; Greene, WIlliam D.; Christenson, Rick L.; Bowen, Barry C.

2007-01-01

The J-2X program calls for the upgrade of the Apollo-era Rocketdyne J-2 engine to higher power levels, using new materials and manufacturing techniques, and with more restrictive safety and reliability requirements than prior human-rated engines in NASA history. Such requirements demand a comprehensive systems engineering effort to ensure success. Pratt & Whitney Rocketdyne system engineers performed a functional analysis of the engine to establish the functional architecture. J-2X functions were captured in six major operational blocks. Each block was divided into sub-blocks or states. In each sub-block, functions necessary to perform each state were determined. A functional engine schematic consistent with the fidelity of the system model was defined for this analysis. The blocks, sub-blocks, and functions were sequentially numbered to differentiate the states in which the function were performed and to indicate the sequence of events. The Engine System was functionally partitioned, to provide separate and unique functional operators. Establishing unique functional operators as work output of the System Architecture process is novel in Liquid Propulsion Engine design. Each functional operator was described such that its unique functionality was identified. The decomposed functions were then allocated to the functional operators both of which were the inputs to the subsystem or component performance specifications. PWR also used a novel approach to identify and map the engine functional requirements to customer-specified functions. The final result was a comprehensive Functional Flow Block Diagram (FFBD) for the J-2X Engine System, decomposed to the component level and mapped to all functional requirements. This FFBD greatly facilitates component specification development, providing a well-defined trade space for functional trades at the subsystem and component level. It also provides a framework for function-based failure modes and effects analysis (FMEA), and a rigorous baseline for the functional architecture.

Advanced space engine preliminary design. [liquid hydrogen/liquid oxygen upper stage engine for space tug application

NASA Technical Reports Server (NTRS)

Zachary, A. T.

1973-01-01

Analysis and design of an optimum LO2/LH2, combustion topping cycle, 88,964 Newtons (20,000-pound) thrust, liquid rocket engine was conducted. The design selected is well suited to high-energy, upper-stage engine applications such as the Space Tug and embodies features directed toward optimization of vehicle performance. A configuration selection was conducted based on prior Air Force Contracts, and additional criteria for optimum stage performance. Following configuration selection, analyses and design of the major components and engine systems were conducted to sufficient depth to provide layout drawings suitable for subsequent detailing. In addition, engine packaging to a common interface and a retractable nozzle concept were defined. Alternative development plans and related costs were also established. The design embodies high-performance, low-weight, low NPSH requirements (saturated propellant inlet conditions at start), idle-mode operation, and autogenous pressurization. The design is the result of the significant past and current LO2/LH2 technology efforts of the NASA centers and the Air Force, as well as company-funded programs.

Software for Collaborative Engineering of Launch Rockets

NASA Technical Reports Server (NTRS)

Stanley, Thomas Troy

2003-01-01

The Rocket Evaluation and Cost Integration for Propulsion and Engineering software enables collaborative computing with automated exchange of information in the design and analysis of launch rockets and other complex systems. RECIPE can interact with and incorporate a variety of programs, including legacy codes, that model aspects of a system from the perspectives of different technological disciplines (e.g., aerodynamics, structures, propulsion, trajectory, aeroheating, controls, and operations) and that are used by different engineers on different computers running different operating systems. RECIPE consists mainly of (1) ISCRM a file-transfer subprogram that makes it possible for legacy codes executed in their original operating systems on their original computers to exchange data and (2) CONES an easy-to-use filewrapper subprogram that enables the integration of legacy codes. RECIPE provides a tightly integrated conceptual framework that emphasizes connectivity among the programs used by the collaborators, linking these programs in a manner that provides some configuration control while facilitating collaborative engineering tradeoff studies, including design to cost studies. In comparison with prior collaborative-engineering schemes, one based on the use of RECIPE enables fewer engineers to do more in less time.

Student Attraction to Engineering through Flexibility and Breadth in the Curriculum

ERIC Educational Resources Information Center

Alpay, E.

2013-01-01

Several European universities provide entry to general engineering studies prior to degree specialisation. The potential advantages of such entry include the provision of a broader foundation in engineering fundamentals, the option for students to defer specialisation until a greater awareness of the different engineering disciplines and the…

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2010 CFR

2010-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2012 CFR

2012-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2014 CFR

2014-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2011 CFR

2011-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

25 CFR 700.465 - Technical feasibility.

Code of Federal Regulations, 2013 CFR

2013-04-01

... construction, technology, or another engineering project, however, an application for a construction, technology or another engineering project shall: (a) Include sufficient information to determine the nature... construction, technology, or other engineering project prior to construction. The Commission shall review the...

D0 Silicon Upgrade: Lower Cleanroom Roof Quick Load Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rucinski, Russ; /Fermilab

1995-11-17

This engineering note documents calculations done to determine the margin of safety for the lower clean room roof. The analysis was done to give me a feeling of what the loads, stresses and capacity of the roof is prior to installation and installation work to be done for the helium refrigerator upgrade. The result of this quick look showed that the calculated loads produce stress values and loads at about half the allowables. Based on this result, I do not think that special precautions above personal judgement are required for the installation work.

Engineering design activities and conceptual change in middle school science

NASA Astrophysics Data System (ADS)

Schnittka, Christine G.

The purpose of this research was to investigate the impact of engineering design classroom activities on conceptual change in science, and on attitudes toward and knowledge about engineering. Students were given a situated learning context and a rationale for learning science in an active, inquiry-based method, and worked in small collaborative groups. One eighth-grade physical science teacher and her students participated in a unit on heat transfer and thermal energy. One class served as the control while two others received variations of an engineering design treatment. Data were gathered from teacher and student entrance and exit interviews, audio recordings of student dialog during group work, video recordings and observations of all classes, pre- and posttests on science content and engineering attitudes, and artifacts and all assignments completed by students. Qualitative and quantitative data were collected concurrently, but analysis took place in two phases. Qualitative data were analyzed in an ongoing manner so that the researcher could explore emerging theories and trends as the study progressed. These results were compared to and combined with the results of the quantitative data analysis. Analysis of the data was carried out in the interpretive framework of analytic induction. Findings indicated that students overwhelmingly possessed alternative conceptions about heat transfer, thermal energy, and engineering prior to the interventions. While all three classes made statistically significant gains in their knowledge about heat and energy, students in the engineering design class with the targeted demonstrations made the most significant gains over the other two other classes. Engineering attitudes changed significantly in the two classes that received the engineering design intervention. Implications from this study can inform teachers' use of engineering design activities in science classrooms. These implications are: (1) Alternative conceptions will persist when not specifically addressed. (2) Engineering design activities are not enough to promote conceptual change. (3) A middle school teacher can successfully implement an engineering design-based curriculum in a science class. (4) Results may also be of interest to science curriculum developers and engineering educators involved in developing engineering outreach curricula for middle school students.

Chris Webber | NREL

Science.gov Websites

Education Undergraduate studies in mechanical engineering, University of Colorado, Denver, CO Undergraduate studies in electrical engineering, University of Texas, Austin, TX Prior Work Experience Deployment

FRONT DETAIL OF RIGHT ENGINE AND WING. MECHANICS CHECK METAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FRONT DETAIL OF RIGHT ENGINE AND WING. MECHANICS CHECK METAL CHIP DETECTOR ON RIGHT ENGINE. THE LEADING EDGE FLAPS ON THE RIGHT WING ARE DOWN PRIOR TO LUBRICATION. - Greater Buffalo International Airport, Maintenance Hangar, Buffalo, Erie County, NY

Clayton Barrows | NREL

Science.gov Websites

engineering, Penn State, 2013 B.S. in electrical engineering, University of Wyoming, 2005 Prior Work of Electrical and Electronics Engineers (IEEE) Featured Publications Barrows, Clayton, Trieu Mai and Electrical Structure of the North American Electric Power Infrastructure." IEEE Systems

40 CFR 90.1204 - Maintenance, aging and testing of engines.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Maintenance, aging and testing of... Voluntary In-Use Testing § 90.1204 Maintenance, aging and testing of engines. (a) Prior to aging the engines... assure that the engines and equipment were properly used and maintained during the field aging process...

40 CFR 90.1204 - Maintenance, aging and testing of engines.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Maintenance, aging and testing of... Voluntary In-Use Testing § 90.1204 Maintenance, aging and testing of engines. (a) Prior to aging the engines... assure that the engines and equipment were properly used and maintained during the field aging process...

40 CFR 90.1204 - Maintenance, aging and testing of engines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Maintenance, aging and testing of... Voluntary In-Use Testing § 90.1204 Maintenance, aging and testing of engines. (a) Prior to aging the engines... assure that the engines and equipment were properly used and maintained during the field aging process...

40 CFR 90.1204 - Maintenance, aging and testing of engines.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Maintenance, aging and testing of... Voluntary In-Use Testing § 90.1204 Maintenance, aging and testing of engines. (a) Prior to aging the engines... assure that the engines and equipment were properly used and maintained during the field aging process...

40 CFR 90.1204 - Maintenance, aging and testing of engines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Maintenance, aging and testing of... Voluntary In-Use Testing § 90.1204 Maintenance, aging and testing of engines. (a) Prior to aging the engines... assure that the engines and equipment were properly used and maintained during the field aging process...

Reversing the Trend of Engineering Enrollment Declines with Innovative Outreach, Recruiting, and Retention Programs

ERIC Educational Resources Information Center

Davis, C. E.; Yeary, M. B.; Sluss, J. J., Jr.

2012-01-01

This paper discusses an all-encompassing approach to increase the number of students in engineering through innovative outreach, recruiting, and retention programs. Prior to adopting these programs, the School of Electrical and Computer Engineering (ECE) at the University of Oklahoma (OU), Norman, experienced a reduction in engineering enrollment…

33 CFR 66.05-40 - Corps of Engineers' approval.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Corps of Engineers' approval. 66... AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-40 Corps of Engineers..., the State Administrator is responsible for obtaining prior permission from the District Engineer, U.S...

33 CFR 66.05-40 - Corps of Engineers' approval.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Corps of Engineers' approval. 66... AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-40 Corps of Engineers..., the State Administrator is responsible for obtaining prior permission from the District Engineer, U.S...

33 CFR 66.05-40 - Corps of Engineers' approval.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Corps of Engineers' approval. 66... AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-40 Corps of Engineers..., the State Administrator is responsible for obtaining prior permission from the District Engineer, U.S...

33 CFR 66.05-40 - Corps of Engineers' approval.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Corps of Engineers' approval. 66... AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-40 Corps of Engineers..., the State Administrator is responsible for obtaining prior permission from the District Engineer, U.S...

33 CFR 66.05-40 - Corps of Engineers' approval.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Corps of Engineers' approval. 66... AIDS TO NAVIGATION PRIVATE AIDS TO NAVIGATION State Aids to Navigation § 66.05-40 Corps of Engineers..., the State Administrator is responsible for obtaining prior permission from the District Engineer, U.S...

Historical Research and Archeological Reconnaissance of the Mandeville Seawall Replacement, St. Tammany Parish, Louisiana

DTIC Science & Technology

1994-01-02

ENGINEERS P0 13OX 60267 NEW ORLEANS LOUISIANA 70160-0267 REPLYTO October 20, 1993 ATTENTION OF Planning Division Environmental Analysis Branch To The...been felled by the commercial timber industry . Documented species include loblolly pine, slash pine, longleaf pine, shortleaf pine, sweetgum, water oak...and amphibians. Open areas, which prior to the timbering industry were uncommon, support bobwhite quail, mourning dove, and rabbit. Marshes, which are

A General Tool for Engineering the NAD/NADP Cofactor Preference of Oxidoreductases.

PubMed

Cahn, Jackson K B; Werlang, Caroline A; Baumschlager, Armin; Brinkmann-Chen, Sabine; Mayo, Stephen L; Arnold, Frances H

2017-02-17

The ability to control enzymatic nicotinamide cofactor utilization is critical for engineering efficient metabolic pathways. However, the complex interactions that determine cofactor-binding preference render this engineering particularly challenging. Physics-based models have been insufficiently accurate and blind directed evolution methods too inefficient to be widely adopted. Building on a comprehensive survey of previous studies and our own prior engineering successes, we present a structure-guided, semirational strategy for reversing enzymatic nicotinamide cofactor specificity. This heuristic-based approach leverages the diversity and sensitivity of catalytically productive cofactor binding geometries to limit the problem to an experimentally tractable scale. We demonstrate the efficacy of this strategy by inverting the cofactor specificity of four structurally diverse NADP-dependent enzymes: glyoxylate reductase, cinnamyl alcohol dehydrogenase, xylose reductase, and iron-containing alcohol dehydrogenase. The analytical components of this approach have been fully automated and are available in the form of an easy-to-use web tool: Cofactor Specificity Reversal-Structural Analysis and Library Design (CSR-SALAD).

Evan Weaver | NREL

Science.gov Websites

Evan Weaver Photo of Evan Weaver Evan Weaver Researcher III-Software Engineering Evan.Weaver , he works as a software engineer developing whole-building energy modeling tools. Prior to joining NREL, he worked in the biomedical industry as a software engineer, specializing in graphical user

14 CFR 34.5 - Special test procedures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES General Provisions § 34.5 Special test... or operator of aircraft or aircraft engines, approve test procedures for any aircraft or aircraft engine that is not susceptible to satisfactory testing by the procedures set forth herein. Prior to...

Shielded regeneration heating element for a particulate filter

DOEpatents

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-01-04

An exhaust system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A catalyst substrate or a flow converter is disposed upstream from said heating element. The catalyst substrate oxidizes the exhaust prior to reception by the heating element. The flow converter converts turbulent exhaust flow to laminar exhaust flow prior to reception by the heating element.

Aerodynamic Database Development for the Hyper-X Airframe Integrated Scramjet Propulsion Experiments

NASA Technical Reports Server (NTRS)

Engelund, Walter C.; Holland, Scott D.; Cockrell, Charles E., Jr.; Bittner, Robert D.

2000-01-01

This paper provides an overview of the activities associated with the aerodynamic database which is being developed in support of NASA's Hyper-X scramjet flight experiments. Three flight tests are planned as part of the Hyper-X program. Each will utilize a small, nonrecoverable research vehicle with an airframe integrated scramjet propulsion engine. The research vehicles will be individually rocket boosted to the scramjet engine test points at Mach 7 and Mach 10. The research vehicles will then separate from the first stage booster vehicle and the scramjet engine test will be conducted prior to the terminal decent phase of the flight. An overview is provided of the activities associated with the development of the Hyper-X aerodynamic database, including wind tunnel test activities and parallel CFD analysis efforts for all phases of the Hyper-X flight tests. A brief summary of the Hyper-X research vehicle aerodynamic characteristics is provided, including the direct and indirect effects of the airframe integrated scramjet propulsion system operation on the basic airframe stability and control characteristics. Brief comments on the planned post flight data analysis efforts are also included.

Engineers in the Classroom: Their Influence on African-American Students' Perceptions of Engineering

ERIC Educational Resources Information Center

Thompson, Stephen; Lyons, Jed

2008-01-01

A Draw an Engineer Test was used to capture the perceptions of engineering held by two similar groups of 6th grade African-American students. Forty-four students who had graduate level engineers in their classrooms during a prior school year as part of a GK-12 project were matched to 44 students who had not. Matching criteria included race,…

Object Based Numerical Zooming Between the NPSS Version 1 and a 1-Dimensional Meanline High Pressure Compressor Design Analysis Code

NASA Technical Reports Server (NTRS)

Follen, G.; Naiman, C.; auBuchon, M.

2000-01-01

Within NASA's High Performance Computing and Communication (HPCC) program, NASA Glenn Research Center is developing an environment for the analysis/design of propulsion systems for aircraft and space vehicles called the Numerical Propulsion System Simulation (NPSS). The NPSS focuses on the integration of multiple disciplines such as aerodynamics, structures, and heat transfer, along with the concept of numerical zooming between 0- Dimensional to 1-, 2-, and 3-dimensional component engine codes. The vision for NPSS is to create a "numerical test cell" enabling full engine simulations overnight on cost-effective computing platforms. Current "state-of-the-art" engine simulations are 0-dimensional in that there is there is no axial, radial or circumferential resolution within a given component (e.g. a compressor or turbine has no internal station designations). In these 0-dimensional cycle simulations the individual component performance characteristics typically come from a table look-up (map) with adjustments for off-design effects such as variable geometry, Reynolds effects, and clearances. Zooming one or more of the engine components to a higher order, physics-based analysis means a higher order code is executed and the results from this analysis are used to adjust the 0-dimensional component performance characteristics within the system simulation. By drawing on the results from more predictive, physics based higher order analysis codes, "cycle" simulations are refined to closely model and predict the complex physical processes inherent to engines. As part of the overall development of the NPSS, NASA and industry began the process of defining and implementing an object class structure that enables Numerical Zooming between the NPSS Version I (0-dimension) and higher order 1-, 2- and 3-dimensional analysis codes. The NPSS Version I preserves the historical cycle engineering practices but also extends these classical practices into the area of numerical zooming for use within a companies' design system. What follows here is a description of successfully zooming I-dimensional (row-by-row) high pressure compressor results back to a NPSS engine 0-dimension simulation and a discussion of the results illustrated using an advanced data visualization tool. This type of high fidelity system-level analysis, made possible by the zooming capability of the NPSS, will greatly improve the fidelity of the engine system simulation and enable the engine system to be "pre-validated" prior to commitment to engine hardware.

Jet engine noise and infrared plume correlation field campaign

NASA Astrophysics Data System (ADS)

Cunio, Phillip M.; Weber, Reed A.; Knobel, Kimberly R.; Smith, Christine; Draudt, Andy

2015-09-01

Jet engine noise can be a health hazard and environmental pollutant, particularly affecting personnel working in close proximity to jet engines, such as airline mechanics. Mitigating noise could reduce the potential for hearing loss in runway workers; however, there exists a very complex relationship between jet engine design parameters, operating conditions, and resultant noise power levels, and understanding and characterizing this relationship is a key step in mitigating jet engine noise effects. We demonstrate initial results highlighting the utility of high-speed imaging (hypertemporal imaging) in correlating the infrared signatures of jet engines with acoustic noise. This paper builds on prior theoretical analysis of jet engine infrared signatures and their potential relationships to jet engine acoustic emissions. This previous work identified the region of the jet plume most likely to emit both in infrared and in acoustic domains, and it prompted the investigation of wave packets as a physical construct tying together acoustic and infrared energy emissions. As a means of verifying these assertions, a field campaign to collect relevant data was proposed, and data collection was carried out with a bank of infrared instruments imaging a T700 turboshaft engine undergoing routine operational testing. The detection of hypertemporal signatures in association with acoustic signatures of jet engines enables the use of a new domain in characterizing jet engine noise. This may in turn enable new methods of predicting or mitigating jet engine noise, which could lead to socioeconomic benefits for airlines and other operators of large numbers of jet engines.

RADC SCAT automated sneak circuit analysis tool

NASA Astrophysics Data System (ADS)

Depalma, Edward L.

The sneak circuit analysis tool (SCAT) provides a PC-based system for real-time identification (during the design phase) of sneak paths and design concerns. The tool utilizes an expert system shell to assist the analyst so that prior experience with sneak analysis is not necessary for performance. Both sneak circuits and design concerns are targeted by this tool, with both digital and analog circuits being examined. SCAT focuses the analysis at the assembly level, rather than the entire system, so that most sneak problems can be identified and corrected by the responsible design engineer in a timely manner. The SCAT program identifies the sneak circuits to the designer, who then decides what course of action is necessary.

Alvin (Al) Sieff: Thoughts About and Lessons from a Great Engineer

NASA Technical Reports Server (NTRS)

Tauber, Michael

2010-01-01

Alvin (Al) Seiff was known as a world-class atmospheric scientist during the last three decades of his life. Equally deserving, however, were his prior achievements as an innovative engineer, an exceptional technical manager, and a mentor of young engineers at NASA Ames Research Center. This paper outlines Al's role in developing Ames ballistic range facilities, probably the most advanced in the world at that time, and his seminal 1963 report that contained the concepts used to reconstruct the atmospheres of Mars, Venus, Jupiter and Titan. Also discussed is my affiliation with Al after he hired me in 1962, including our joint work on Mars missions and investigating the feasibility that a Jupiter probe could survive entry, work that eventually led to the development of the Galileo probe. Finally, suggestions are offered for speeding the analysis and design of thermal protection systems based on lessons learned from successful probes and landers.

Long-term CF6 engine performance deterioration: Evaluation of engine S/N 451-380

NASA Technical Reports Server (NTRS)

Kramer, W. H.; Smith, J. J.

1978-01-01

The performance testing and analytical teardown of CF6-6D engine serial number 451-380 which was recently removed from a DC-10 aircraft is summarized. The investigative test program was conducted inbound prior to normal overhaul/refurbishment. The performance testing included an inbound test, a test following cleaning of the low pressure turbine airfoils, and a final test after leading edge rework and cleaning the stage one fan blades. The analytical teardown consisted of detailed disassembly inspection measurements and airfoil surface finish checks of the as-received deteriorated hardware. Aspects discussed include the analysis of the test cell performance data, a complete analytical teardown report with a detailed description of all observed hardware distress, and an analytical assessment of the performance loss (deterioration) relating measured hardware conditions to losses in both specific fuel comsumption and exhaust gas temperature.

Recent advances in the evolutionary engineering of industrial biocatalysts.

PubMed

Winkler, James D; Kao, Katy C

2014-12-01

Evolutionary engineering has been used to improve key industrial strain traits, such as carbon source utilization, tolerance to adverse environmental conditions, and resistance to chemical inhibitors, for many decades due to its technical simplicity and effectiveness. The lack of need for prior genetic knowledge underlying the phenotypes of interest makes this a powerful approach for strain development for even species with minimal genotypic information. While the basic experimental procedure for laboratory adaptive evolution has remained broadly similar for many years, a range of recent advances show promise for improving the experimental workflows for evolutionary engineering by accelerating the pace of evolution, simplifying the analysis of evolved mutants, and providing new ways of linking desirable phenotypes to selectable characteristics. This review aims to highlight some of these recent advances and discuss how they may be used to improve industrially relevant microbial phenotypes. Copyright © 2014 Elsevier Inc. All rights reserved.

40 CFR 90.1003 - Prohibited acts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to use noncertified nonroad engines built prior to the applicable implementation date of the Phase 1... the Phase 2 regulations in this part, nonroad vehicle and equipment manufacturers may continue to use Phase 1 engines until Phase 1 engine inventories are depleted. Stockpiling (i.e., build up of an...

40 CFR 90.1003 - Prohibited acts.

Code of Federal Regulations, 2013 CFR

2013-07-01

... to use noncertified nonroad engines built prior to the applicable implementation date of the Phase 1... the Phase 2 regulations in this part, nonroad vehicle and equipment manufacturers may continue to use Phase 1 engines until Phase 1 engine inventories are depleted. Stockpiling (i.e., build up of an...

40 CFR 90.1003 - Prohibited acts.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to use noncertified nonroad engines built prior to the applicable implementation date of the Phase 1... the Phase 2 regulations in this part, nonroad vehicle and equipment manufacturers may continue to use Phase 1 engines until Phase 1 engine inventories are depleted. Stockpiling (i.e., build up of an...

40 CFR 90.1003 - Prohibited acts.

Code of Federal Regulations, 2012 CFR

2012-07-01

... to use noncertified nonroad engines built prior to the applicable implementation date of the Phase 1... the Phase 2 regulations in this part, nonroad vehicle and equipment manufacturers may continue to use Phase 1 engines until Phase 1 engine inventories are depleted. Stockpiling (i.e., build up of an...

A Bayesian approach to meta-analysis of plant pathology studies.

PubMed

Mila, A L; Ngugi, H K

2011-01-01

Bayesian statistical methods are used for meta-analysis in many disciplines, including medicine, molecular biology, and engineering, but have not yet been applied for quantitative synthesis of plant pathology studies. In this paper, we illustrate the key concepts of Bayesian statistics and outline the differences between Bayesian and classical (frequentist) methods in the way parameters describing population attributes are considered. We then describe a Bayesian approach to meta-analysis and present a plant pathological example based on studies evaluating the efficacy of plant protection products that induce systemic acquired resistance for the management of fire blight of apple. In a simple random-effects model assuming a normal distribution of effect sizes and no prior information (i.e., a noninformative prior), the results of the Bayesian meta-analysis are similar to those obtained with classical methods. Implementing the same model with a Student's t distribution and a noninformative prior for the effect sizes, instead of a normal distribution, yields similar results for all but acibenzolar-S-methyl (Actigard) which was evaluated only in seven studies in this example. Whereas both the classical (P = 0.28) and the Bayesian analysis with a noninformative prior (95% credibility interval [CRI] for the log response ratio: -0.63 to 0.08) indicate a nonsignificant effect for Actigard, specifying a t distribution resulted in a significant, albeit variable, effect for this product (CRI: -0.73 to -0.10). These results confirm the sensitivity of the analytical outcome (i.e., the posterior distribution) to the choice of prior in Bayesian meta-analyses involving a limited number of studies. We review some pertinent literature on more advanced topics, including modeling of among-study heterogeneity, publication bias, analyses involving a limited number of studies, and methods for dealing with missing data, and show how these issues can be approached in a Bayesian framework. Bayesian meta-analysis can readily include information not easily incorporated in classical methods, and allow for a full evaluation of competing models. Given the power and flexibility of Bayesian methods, we expect them to become widely adopted for meta-analysis of plant pathology studies.

Money, Math and Engineering: The Relationships between Community Economics, Math Preparation and the Graduation of Racially Underrepresented Engineers

ERIC Educational Resources Information Center

Freeman, Amy Louise

2009-01-01

A primary gateway to a career in engineering is the attainment of the bachelor of science degree in engineering. In contrast, a common barrier to becoming an engineer is failure to attain the degree. Those variables that are related to college graduation are often in place prior to college admission. The purpose of this study was to examine the…

40 CFR 86.1380-2004 - Load response test.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) The test has 5 separate measurement segments, each identified by a specific engine speed. At each of the following speeds, beginning with the lowest torque point at that engine speed within the NTE.... Prior to the beginning of each measurement segment, the engine shall be warmed up at the supplemental...

40 CFR 86.1380-2004 - Load response test.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) The test has 5 separate measurement segments, each identified by a specific engine speed. At each of the following speeds, beginning with the lowest torque point at that engine speed within the NTE.... Prior to the beginning of each measurement segment, the engine shall be warmed up at the supplemental...

40 CFR 86.1380-2004 - Load response test.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) The test has 5 separate measurement segments, each identified by a specific engine speed. At each of the following speeds, beginning with the lowest torque point at that engine speed within the NTE.... Prior to the beginning of each measurement segment, the engine shall be warmed up at the supplemental...

40 CFR 86.1380-2004 - Load response test.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) The test has 5 separate measurement segments, each identified by a specific engine speed. At each of the following speeds, beginning with the lowest torque point at that engine speed within the NTE.... Prior to the beginning of each measurement segment, the engine shall be warmed up at the supplemental...

75 FR 19428 - Advisory Committee for Computer and Information Science and Engineering; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-14

... Engineering; Notice of Meeting In accordance with the Federal Advisory Committee Act (Pub. L. 92- 463, as... Computer and Information Science and Engineering--(1115). Date and Time: May 7, 2010, 8:30 a.m.-5 p.m... Information Science and Engineering at 703/292-8900 prior to the meeting so that a visitor's badge may be...

40 CFR 68.56 - Maintenance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL... testing procedures shall follow recognized and generally accepted good engineering practices. The...' recommendations, industry standards or codes, good engineering practices, and prior operating experience. ...

40 CFR 68.56 - Maintenance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL... testing procedures shall follow recognized and generally accepted good engineering practices. The...' recommendations, industry standards or codes, good engineering practices, and prior operating experience. ...

40 CFR 68.56 - Maintenance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL... testing procedures shall follow recognized and generally accepted good engineering practices. The...' recommendations, industry standards or codes, good engineering practices, and prior operating experience. ...

40 CFR 68.56 - Maintenance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL... testing procedures shall follow recognized and generally accepted good engineering practices. The...' recommendations, industry standards or codes, good engineering practices, and prior operating experience. ...

40 CFR 68.56 - Maintenance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL... testing procedures shall follow recognized and generally accepted good engineering practices. The...' recommendations, industry standards or codes, good engineering practices, and prior operating experience. ...

Maximizing the sensitivity and reliability of peptide identification in large-scale proteomic experiments by harnessing multiple search engines.

PubMed

Yu, Wen; Taylor, J Alex; Davis, Michael T; Bonilla, Leo E; Lee, Kimberly A; Auger, Paul L; Farnsworth, Chris C; Welcher, Andrew A; Patterson, Scott D

2010-03-01

Despite recent advances in qualitative proteomics, the automatic identification of peptides with optimal sensitivity and accuracy remains a difficult goal. To address this deficiency, a novel algorithm, Multiple Search Engines, Normalization and Consensus is described. The method employs six search engines and a re-scoring engine to search MS/MS spectra against protein and decoy sequences. After the peptide hits from each engine are normalized to error rates estimated from the decoy hits, peptide assignments are then deduced using a minimum consensus model. These assignments are produced in a series of progressively relaxed false-discovery rates, thus enabling a comprehensive interpretation of the data set. Additionally, the estimated false-discovery rate was found to have good concordance with the observed false-positive rate calculated from known identities. Benchmarking against standard proteins data sets (ISBv1, sPRG2006) and their published analysis, demonstrated that the Multiple Search Engines, Normalization and Consensus algorithm consistently achieved significantly higher sensitivity in peptide identifications, which led to increased or more robust protein identifications in all data sets compared with prior methods. The sensitivity and the false-positive rate of peptide identification exhibit an inverse-proportional and linear relationship with the number of participating search engines.

Incorporation of stochastic engineering models as prior information in Bayesian medical device trials.

PubMed

Haddad, Tarek; Himes, Adam; Thompson, Laura; Irony, Telba; Nair, Rajesh

2017-01-01

Evaluation of medical devices via clinical trial is often a necessary step in the process of bringing a new product to market. In recent years, device manufacturers are increasingly using stochastic engineering models during the product development process. These models have the capability to simulate virtual patient outcomes. This article presents a novel method based on the power prior for augmenting a clinical trial using virtual patient data. To properly inform clinical evaluation, the virtual patient model must simulate the clinical outcome of interest, incorporating patient variability, as well as the uncertainty in the engineering model and in its input parameters. The number of virtual patients is controlled by a discount function which uses the similarity between modeled and observed data. This method is illustrated by a case study of cardiac lead fracture. Different discount functions are used to cover a wide range of scenarios in which the type I error rates and power vary for the same number of enrolled patients. Incorporation of engineering models as prior knowledge in a Bayesian clinical trial design can provide benefits of decreased sample size and trial length while still controlling type I error rate and power.

14. Wayne Chandler, Photographer, May 2000 Photographic copy of engineering ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Wayne Chandler, Photographer, May 2000 Photographic copy of engineering drawings, dated 1917, by U.S. Army Corps of Engineers. Drawing in possession of U.S. Army Corps of Engineers, Sault Ste. Marie, Michigan. General plan of locks prior to completion of Sabin (fourth) Lock - St. Mary's Falls Canal, Soo Locks, St. Mary's River at Falls, Sault Ste. Marie, Chippewa County, MI

Support for non-locking parallel reception of packets belonging to a single memory reception FIFO

DOEpatents

Chen, Dong [Yorktown Heights, NY; Heidelberger, Philip [Yorktown Heights, NY; Salapura, Valentina [Yorktown Heights, NY; Senger, Robert M [Yorktown Heights, NY; Steinmacher-Burow, Burkhard [Boeblingen, DE; Sugawara, Yutaka [Yorktown Heights, NY

2011-01-27

A method and apparatus for distributed parallel messaging in a parallel computing system. A plurality of DMA engine units are configured in a multiprocessor system to operate in parallel, one DMA engine unit for transferring a current packet received at a network reception queue to a memory location in a memory FIFO (rmFIFO) region of a memory. A control unit implements logic to determine whether any prior received packet destined for that rmFIFO is still in a process of being stored in the associated memory by another DMA engine unit of the plurality, and prevent the one DMA engine unit from indicating completion of storing the current received packet in the reception memory FIFO (rmFIFO) until all prior received packets destined for that rmFIFO are completely stored by the other DMA engine units. Thus, there is provided non-locking support so that multiple packets destined for a single rmFIFO are transferred and stored in parallel to predetermined locations in a memory.

30 CFR 7.88 - Test to determine the gaseous ventilation rate.

Code of Federal Regulations, 2013 CFR

2013-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Diesel Engines... engine to the dynamometer and attach the sampling and measurement devices specified in § 7.86. (2) A... zeroed and spanned at the analyzer range to be used prior to testing. (4) Run the engine. (i) The...

30 CFR 7.88 - Test to determine the gaseous ventilation rate.

Code of Federal Regulations, 2014 CFR

2014-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Diesel Engines... engine to the dynamometer and attach the sampling and measurement devices specified in § 7.86. (2) A... zeroed and spanned at the analyzer range to be used prior to testing. (4) Run the engine. (i) The...

30 CFR 7.88 - Test to determine the gaseous ventilation rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Diesel Engines... engine to the dynamometer and attach the sampling and measurement devices specified in § 7.86. (2) A... zeroed and spanned at the analyzer range to be used prior to testing. (4) Run the engine. (i) The...

30 CFR 7.88 - Test to determine the gaseous ventilation rate.

Code of Federal Regulations, 2012 CFR

2012-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Diesel Engines... engine to the dynamometer and attach the sampling and measurement devices specified in § 7.86. (2) A... zeroed and spanned at the analyzer range to be used prior to testing. (4) Run the engine. (i) The...

30 CFR 7.88 - Test to determine the gaseous ventilation rate.

Code of Federal Regulations, 2011 CFR

2011-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Diesel Engines... engine to the dynamometer and attach the sampling and measurement devices specified in § 7.86. (2) A... zeroed and spanned at the analyzer range to be used prior to testing. (4) Run the engine. (i) The...

Pathways to Engineering: The Validation Experiences of Transfer Students

ERIC Educational Resources Information Center

Zhang, Yi; Ozuna, Taryn

2015-01-01

Community college engineering transfer students are a critical student population of engineering degree recipients and technical workforce in the United States. Focusing on this group of students, we adopted Rendón's (1994) validation theory to explore the students' experiences in community colleges prior to transferring to a four-year…

Gaming, texting, learning? Teaching engineering ethics through students' lived experiences with technology.

PubMed

Voss, Georgina

2013-09-01

This paper examines how young peoples' lived experiences with personal technologies can be used to teach engineering ethics in a way which facilitates greater engagement with the subject. Engineering ethics can be challenging to teach: as a form of practical ethics, it is framed around future workplace experience in a professional setting which students are assumed to have no prior experience of. Yet the current generations of engineering students, who have been described as 'digital natives', do however have immersive personal experience with digital technologies; and experiential learning theory describes how students learn ethics more successfully when they can draw on personal experience which give context and meaning to abstract theories. This paper reviews current teaching practices in engineering ethics; and examines young people's engagement with technologies including cell phones, social networking sites, digital music and computer games to identify social and ethical elements of these practices which have relevance for the engineering ethics curricula. From this analysis three case studies are developed to illustrate how facets of the use of these technologies can be drawn on to teach topics including group work and communication; risk and safety; and engineering as social experimentation. Means for bridging personal experience and professional ethics when teaching these cases are discussed. The paper contributes to research and curriculum development in engineering ethics education, and to wider education research about methods of teaching 'the net generation'.

Understanding safety and production risks in rail engineering planning and protection.

PubMed

Wilson, John R; Ryan, Brendan; Schock, Alex; Ferreira, Pedro; Smith, Stuart; Pitsopoulos, Julia

2009-07-01

Much of the published human factors work on risk is to do with safety and within this is concerned with prediction and analysis of human error and with human reliability assessment. Less has been published on human factors contributions to understanding and managing project, business, engineering and other forms of risk and still less jointly assessing risk to do with broad issues of 'safety' and broad issues of 'production' or 'performance'. This paper contains a general commentary on human factors and assessment of risk of various kinds, in the context of the aims of ergonomics and concerns about being too risk averse. The paper then describes a specific project, in rail engineering, where the notion of a human factors case has been employed to analyse engineering functions and related human factors issues. A human factors issues register for potential system disturbances has been developed, prior to a human factors risk assessment, which jointly covers safety and production (engineering delivery) concerns. The paper concludes with a commentary on the potential relevance of a resilience engineering perspective to understanding rail engineering systems risk. Design, planning and management of complex systems will increasingly have to address the issue of making trade-offs between safety and production, and ergonomics should be central to this. The paper addresses the relevant issues and does so in an under-published domain - rail systems engineering work.

Sex segregation in undergraduate engineering majors

NASA Astrophysics Data System (ADS)

Litzler, Elizabeth

Gender inequality in engineering persists in spite of women reaching parity in college enrollments and degrees granted. To date, no analyses of educational sex segregation have comprehensively examined segregation within one discipline. To move beyond traditional methods of studying the long-standing stratification by field of study in higher education, I explore gender stratification within one field: engineering. This dissertation investigates why some engineering disciplines have a greater representation of women than other engineering disciplines. I assess the individual and institutional factors and conditions associated with women's representation in certain engineering departments and compare the mechanisms affecting women's and men's choice of majors. I use national data from the Engineering Workforce Commission, survey data from 21 schools in the Project to Assess Climate in Engineering study, and Carnegie Foundation classification information to study sex segregation in engineering majors from multiple perspectives: the individual, major, institution, and country. I utilize correlations, t-tests, cross-tabulations, log-linear modeling, multilevel logistic regression and weighted least squares regression to test the relative utility of alternative explanations for women's disproportionate representation across engineering majors. As a whole, the analyses illustrate the importance of context and environment for women's representation in engineering majors. Hypotheses regarding hostile climate and discrimination find wide support across different analyses, suggesting that women's under-representation in certain engineering majors is not a question of choice or ability. However, individual level factors such as having engineering coursework prior to college show an especially strong association with student choice of major. Overall, the analyses indicate that institutions matter, albeit less for women, and women's under-representation in engineering is not reducible to individual choice. This dissertation provides a broad, descriptive view of the state of sex segregation in engineering as well as a careful analysis of how individual and institutional factors inhibit or encourage sex segregation. This study contributes to the research literature through the use of novel data, testing of occupational segregation theories, and the use of multiple levels of analysis. The analyses provide new insight into an enduring phenomenon, and suggest new avenues for understanding sex segregation in higher education.

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

Expedition 23 Flight Engineer Tracy Caldwell Dyson, front left, Expedition 23 Soyuz Commander Alexander Skvortsov, front center, and Expedition 23 Flight Engineer Mikhail Kornienko pose with backup crewmembers NASA Flight Engineer Scott Kelly of the U.S., back left, Flight Engineer Alexander Samokutyayev of Russia, back center, and Flight Engineer Andrei Borisenko of Russia, prior to the crews’ launch onboard a Soyuz rocket to the International Space Station on Friday, April 2, 2010, in Baikonur, Kazakhstan. Photo Credit: (NASA/Carla Cioffi)

The structural approach to shared knowledge: an application to engineering design teams.

PubMed

Avnet, Mark S; Weigel, Annalisa L

2013-06-01

We propose a methodology for analyzing shared knowledge in engineering design teams. Whereas prior work has focused on shared knowledge in small teams at a specific point in time, the model presented here is both scalable and dynamic. By quantifying team members' common views of design drivers, we build a network of shared mental models to reveal the structure of shared knowledge at a snapshot in time. Based on a structural comparison of networks at different points in time, a metric of change in shared knowledge is computed. Analysis of survey data from 12 conceptual space mission design sessions reveals a correlation between change in shared knowledge and each of several system attributes, including system development time, system mass, and technological maturity. From these results, we conclude that an early period of learning and consensus building could be beneficial to the design of engineered systems. Although we do not examine team performance directly, we demonstrate that shared knowledge is related to the technical design and thus provide a foundation for improving design products by incorporating the knowledge and thoughts of the engineering design team into the process.

A Study of Experience Credit for Professional Engineering Licensure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, M.A.

2003-08-11

Oak Ridge National Laboratory performed a study of experience credit for professional engineering licensure for the Department of Energy's Industrial Assessment Center (IAC) Program. One of the study's goals was to determine how state licensure boards grant experience credit for engineering licensure, particularly in regards to IAC experience and experience prior to graduation. Another goal involved passing IAC information to state licensure boards to allow the boards to become familiar with the program and determine if they would grant credit to IAC graduates. The National Council of Examiners for Engineers and Surveyors (NCEES) has adopted a document, the ''Model Law''.more » This document empowers states to create state engineering boards and oversee engineering licensure. The board can also interpret and adopt rules and regulations. The Model Law also gives a general ''process'' for engineering licensure, the ''Model Law Engineer''. The Model Law Engineer requires that an applicant for professional licensure, or professional engineering (PE) licensure, obtain a combination of formal education and professional experience and successfully complete the fundamentals of engineering (FE) and PE exams. The Model Law states that a PE applicant must obtain four years of ''acceptable'' engineering experience after graduation to be allowed to sit for the PE exam. Although the Model Law defines ''acceptable experience,'' it is somewhat open to interpretation, and state boards decide whether applicants have accumulated the necessary amount of experience. The Model Law also allows applicants one year of credit for postgraduate degrees as well as experience credit for teaching courses in engineering. The Model Law grants states the power to adopt and amend the bylaws and rules of the Model Law licensure process. It allows state boards the freedom to modify the experience requirements for professional licensure. This power has created variety in experience requirements, and licensure requirements can differ from state to state. Before this study began, six questions were developed to help document how state boards grant experience credit. Many of the questions were formulated to determine how states deal with teaching experience, postgraduate credit, experience prior to graduation, PE and FE waivers, and the licensure process in general. Data were collected from engineering licensure boards for each of the fifty states and the District of Columbia. Telephone interviews were the primary method of data collection, while email correspondence was also used to a lesser degree. Prior to contacting each board, the researchers attempted to review each state's licensure web site. Based on the data collected, several trends and patterns were identified. For example, there is a general trend away from offering credit for experience prior to graduation. The issue becomes a problem when a PE from one state attempts to gain a license in another state by comity or endorsement. Tennessee and Kansas have recently stopped offering this credit and Mississippi cautions applicants that it could be difficult to obtain licensure in other states.« less

Steve Nixon | NREL

Science.gov Websites

NREL. Steve has an extensive background in facilities engineering, facilities management, and Energy Manager, and a Project Management Professional. Prior to joining NREL, Steve was the Facilities manufacturing engineering, business application programming, and business process management positions

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2014 CFR

2014-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2010 CFR

2010-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2011 CFR

2011-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2012 CFR

2012-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

49 CFR 268.21 - Down-selection of one or more Maglev projects for further study and selection of one project for...

Code of Federal Regulations, 2013 CFR

2013-10-01

... further study and selection of one project for final design, engineering, and construction funding. 268.21... and selection of one project for final design, engineering, and construction funding. (a) Upon... analyses necessary prior to initiation of construction. Final design and engineering work will also be...

Nonlocal sparse model with adaptive structural clustering for feature extraction of aero-engine bearings

NASA Astrophysics Data System (ADS)

Zhang, Han; Chen, Xuefeng; Du, Zhaohui; Li, Xiang; Yan, Ruqiang

2016-04-01

Fault information of aero-engine bearings presents two particular phenomena, i.e., waveform distortion and impulsive feature frequency band dispersion, which leads to a challenging problem for current techniques of bearing fault diagnosis. Moreover, although many progresses of sparse representation theory have been made in feature extraction of fault information, the theory also confronts inevitable performance degradation due to the fact that relatively weak fault information has not sufficiently prominent and sparse representations. Therefore, a novel nonlocal sparse model (coined NLSM) and its algorithm framework has been proposed in this paper, which goes beyond simple sparsity by introducing more intrinsic structures of feature information. This work adequately exploits the underlying prior information that feature information exhibits nonlocal self-similarity through clustering similar signal fragments and stacking them together into groups. Within this framework, the prior information is transformed into a regularization term and a sparse optimization problem, which could be solved through block coordinate descent method (BCD), is formulated. Additionally, the adaptive structural clustering sparse dictionary learning technique, which utilizes k-Nearest-Neighbor (kNN) clustering and principal component analysis (PCA) learning, is adopted to further enable sufficient sparsity of feature information. Moreover, the selection rule of regularization parameter and computational complexity are described in detail. The performance of the proposed framework is evaluated through numerical experiment and its superiority with respect to the state-of-the-art method in the field is demonstrated through the vibration signals of experimental rig of aircraft engine bearings.

Combustion Stability Characteristics of the Project Morpheus Liquid Oxygen/Liquid Methane Main Engine

NASA Technical Reports Server (NTRS)

Melcher, J. C.; Morehead, Robert L.

2014-01-01

The Project Morpheus liquid oxygen (LOX) / liquid methane rocket engines demonstrated acousticcoupled combustion instabilities during sea-level ground-based testing at the NASA Johnson Space Center (JSC) and Stennis Space Center (SSC). High-amplitude, 1T, 1R, 1T1R (and higher order) modes appear to be triggered by injector conditions. The instability occurred during the Morpheus-specific engine ignition/start sequence, and did demonstrate the capability to propagate into mainstage. However, the instability was never observed to initiate during mainstage, even at low power levels. The Morpheus main engine is a JSC-designed 5,000 lbf-thrust, 4:1 throttling, pressure-fed cryogenic engine using an impinging element injector design. Two different engine designs, named HD4 and HD5, and two different builds of the HD4 engine all demonstrated similar instability characteristics. Through the analysis of more than 200 hot fire tests on the Morpheus vehicle and SSC test stand, a relationship between ignition stability and injector/chamber pressure was developed. The instability has the distinct characteristic of initiating at high relative injection pressure drop (dP) at low chamber pressure (Pc); i.e., instabilities initiated at high dP/Pc at low Pc during the start sequence. The high dP/Pc during start results during the injector /chamber chill-in, and is enhanced by hydraulic flip in the injector orifice elements. Because of the fixed mixture ratio of the existing engine design (the main valves share a common actuator), it is not currently possible to determine if LOX or methane injector dP/Pc were individual contributors (i.e., LOX and methane dP/Pc typically trend in the same direction within a given test). The instability demonstrated initiation characteristic of starting at or shortly after methane injector chillin. Colder methane (e.g., sub-cooled) at the injector inlet prior to engine start was much more likely to result in an instability. A secondary effect of LOX sub-cooling was also possibly observed; greater LOX sub- cooling improved stability. Some tests demonstrated a low-amplitude 1L-1T instability prior to LOX injector chill-in. The Morpheus main engine also demonstrated chug instabilities during some engine shutdown sequences on the flight vehicle and SSC test stand. The chug instability was also infrequently observed during the startup sequence. The chug instabilities predictably initiated at low dP/Pc at low Pc. The chug instabilities were always self-limiting; startup chug instabilities terminated during throttle-up and shutdown chug instabilities decayed by shutdown termination.

40 CFR 89.321 - Oxides of nitrogen analyzer calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... (b) Prior to its introduction into service, and monthly thereafter, the chemiluminescent oxides of... periodic calibration. Prior to its introduction into service, after any maintenance which could alter... represent good engineering practice. For each range calibrated, if the deviation from a least-squares best...

Development of Management Metrics for Research and Technology

NASA Technical Reports Server (NTRS)

Sheskin, Theodore J.

2003-01-01

Professor Ted Sheskin from CSU will be tasked to research and investigate metrics that can be used to determine the technical progress for advanced development and research tasks. These metrics will be implemented in a software environment that hosts engineering design, analysis and management tools to be used to support power system and component research work at GRC. Professor Sheskin is an Industrial Engineer and has been involved in issues related to management of engineering tasks and will use his knowledge from this area to allow extrapolation into the research and technology management area. Over the course of the summer, Professor Sheskin will develop a bibliography of management papers covering current management methods that may be applicable to research management. At the completion of the summer work we expect to have him recommend a metric system to be reviewed prior to implementation in the software environment. This task has been discussed with Professor Sheskin and some review material has already been given to him.

Efficient utilization of graphics technology for space animation

NASA Technical Reports Server (NTRS)

Panos, Gregory Peter

1989-01-01

Efficient utilization of computer graphics technology has become a major investment in the work of aerospace engineers and mission designers. These new tools are having a significant impact in the development and analysis of complex tasks and procedures which must be prepared prior to actual space flight. Design and implementation of useful methods in applying these tools has evolved into a complex interaction of hardware, software, network, video and various user interfaces. Because few people can understand every aspect of this broad mix of technology, many specialists are required to build, train, maintain and adapt these tools to changing user needs. Researchers have set out to create systems where an engineering designer can easily work to achieve goals with a minimum of technological distraction. This was accomplished with high-performance flight simulation visual systems and supercomputer computational horsepower. Control throughout the creative process is judiciously applied while maintaining generality and ease of use to accommodate a wide variety of engineering needs.

A Study of Second-Year Engineering Students' Alternative Conceptions about Electric Potential, Current Intensity and Ohm's Law

ERIC Educational Resources Information Center

Periago, M. Cristina; Bohigas, Xavier

2005-01-01

The aim of this research was to evaluate and analyse second-year industrial engineering and chemical engineering students prior knowledge of conceptual aspects of "circuit theory". Specifically, we focused on the basic concepts of electric potential and current intensity and on the fundamental relationship between them as expressed by Ohm's law.…

The organism is the product.

PubMed

Kelly, Jason

2012-01-20

A new industry model is emerging where microbes are first developed by specialist organism engineering firms and then deployed by customers in specific application areas. It is now realistic for companies without prior fermentation experience to purchase and deploy an engineered organism to expand their business.

32 CFR 644.165 - Purpose and scope.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ESTATE HANDBOOK Acquisition Procurement of Options Prior to Real Estate Directives (military) § 644.165... options to purchase real estate interests for Army or Air Force military requirements prior to the issuance of a real estate directive. These procedures are applicable to all Division and District Engineers...

Seal Technology Development for Advanced Component for Airbreathing Engines

NASA Technical Reports Server (NTRS)

Snyder, Philip H.

2008-01-01

Key aspects of the design of sealing systems for On Rotor Combustion/Wave Rotor (ORC/WR) systems were addressed. ORC/WR systems generally fit within a broad class of pressure gain Constant Volume Combustors (CVCs) or Pulse Detonation Combustors (PDCs) which are currently being considered for use in many classes of turbine engines for dramatic efficiency improvement. Technology readiness level of this ORC/WR approaches are presently at 2.0. The results of detailed modeling of an ORC/WR system as applied to a regional jet engine application were shown to capture a high degree of pressure gain capabilities. The results of engine cycle analysis indicated the level of specific fuel consumption (SFC) benefits to be 17 percent. The potential losses in pressure gain due to leakage were found to be closely coupled to the wave processes at the rotor endpoints of the ORC/WR system. Extensive investigation into the sealing approaches is reported. Sensitivity studies show that SFC gains of 10 percent remain available even when pressure gain levels are highly penalized. This indicates ORC/WR systems to have a high degree of tolerance to rotor leakage effects but also emphasizes their importance. An engine demonstration of an ORC/WR system is seen as key to progressing the TRL of this technology. An industrial engine was judged to be a highly advantageous platform for demonstration of a first generation ORC/WR system. Prior to such a demonstration, the existing NASA pressure exchanger wave rotor rig was identified as an opportunity to apply both expanded analytical modeling capabilities developed within this program and to identify and fix identified leakage issues existing within this rig. Extensive leakage analysis of the rig was performed and a detailed design of additional sealing strategies for this rig was generated.

Bayesian network prior: network analysis of biological data using external knowledge

PubMed Central

Isci, Senol; Dogan, Haluk; Ozturk, Cengizhan; Otu, Hasan H.

2014-01-01

Motivation: Reverse engineering GI networks from experimental data is a challenging task due to the complex nature of the networks and the noise inherent in the data. One way to overcome these hurdles would be incorporating the vast amounts of external biological knowledge when building interaction networks. We propose a framework where GI networks are learned from experimental data using Bayesian networks (BNs) and the incorporation of external knowledge is also done via a BN that we call Bayesian Network Prior (BNP). BNP depicts the relation between various evidence types that contribute to the event ‘gene interaction’ and is used to calculate the probability of a candidate graph (G) in the structure learning process. Results: Our simulation results on synthetic, simulated and real biological data show that the proposed approach can identify the underlying interaction network with high accuracy even when the prior information is distorted and outperforms existing methods. Availability: Accompanying BNP software package is freely available for academic use at http://bioe.bilgi.edu.tr/BNP. Contact: hasan.otu@bilgi.edu.tr Supplementary Information: Supplementary data are available at Bioinformatics online. PMID:24215027

Aircraft Engine Systems

NASA Technical Reports Server (NTRS)

Veres, Joseph P.

2003-01-01

The objective is to develop the capability to numerically model the performance of gas turbine engines used for aircraft propulsion. This capability will provide turbine engine designers with a means of accurately predicting the performance of new engines in a system environment prior to building and testing. The 'numerical test cell' developed under this project will reduce the number of component and engine tests required during development. As a result, the project will help to reduce the design cycle time and cost of gas turbine engines. This capability will be distributed to U.S. turbine engine manufacturers and air framers. This project focuses on goals of maintaining U.S. superiority in commercial gas turbine engine development for the aeronautics industry.

The dish-Rankine SCSTPE program (Engineering Experiment no. 1). [systems engineering and economic analysis for a small community solar thermal electric system

NASA Technical Reports Server (NTRS)

Pons, R. L.; Grigsby, C. E.

1980-01-01

Activities planned for phase 2 Of the Small Community Solar Thermal Power Experiment (PFDR) program are summarized with emphasis on a dish-Rankine point focusing distributed receiver solar thermal electric system. Major design efforts include: (1) development of an advanced concept indirect-heated receiver;(2) development of hardware and software for a totally unmanned power plant control system; (3) implementation of a hybrid digital simulator which will validate plant operation prior to field testing; and (4) the acquisition of an efficient organic Rankine cycle power conversion unit. Preliminary performance analyses indicate that a mass-produced dish-Rankine PFDR system is potentially capable of producing electricity at a levelized busbar energy cost of 60 to 70 mills per KWh and with a capital cost of about $1300 per KW.

SER assistant: An expert system for safety evaluation reports

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeChaine, M.D.; Levine, S.H.; Feltus, M.A.

1993-01-01

The SER Assistant is an expert system that assists engineers to write safety evaluation reports (SERs). Section 50.59 of the Code of Federal Regulations allows modifications to be made to nuclear power plants without prior US Nuclear Regulatory Commission approval if two conditions are satisfied. First, the change must not affect the technical specifications of the plant. Second, the modification must not affect a part of the plant described in the final safety analysis report, or if it does, it must not create an unreviewed safety question. The purpose of an SER is to ensure that these conditions are satisfiedmore » for the proposed modification. The SER Assistant aids this process by providing relevant, but directed, questions and information as well as giving engineers an organized environment to document their thought processes.« less

High Pressure Reverse Flow APS Engine

NASA Technical Reports Server (NTRS)

Senneff, J. M.

1972-01-01

A design and test demonstration effort was undertaken to evaluate the concept of the reverse flow engine for the APS engine application. The 1500 lb (6672 N) thrust engine was designed to operate on gaseous hydrogen and gaseous oxygen propellants at a mixture ratio of 4 and to achieve the objective performance of 435 sec (4266 Nsec/kg) specific impulse. Superimposed durability requirements called for a million-cycle capability with 50 hours duration. The program was undertaken as a series of tasks including the initial preliminary design, design of critical test components and finally, the design and demonstration of an altitude engine which could be used interchangeably to examine operating parameters as well as to demonstrate the capability of the concept. The program results are reported with data to indicate that all of the program objectives were met or exceeded within the course of testing on the program. The analysis effort undertaken is also reported in detail and supplemented with test data in some cases where prior definitions could not be made. The results are contained of these analyses as well as the test results conducted throughout the course of the program. Finally, the test data and analytical results were combined to allow recommendations for a flight weight design. This preliminary design effort is also detailed.

Alex Swindler | NREL

Science.gov Websites

distributed computing, Web information systems engineering, software engineering, computer graphics, and Dashboard, NREL Energy Story visualization, Green Button data integration, as well as a large number of Web of an R&D 100 Award. Prior to joining NREL, Alex worked as a system administrator, Web developer

Lubricity of biobased diesel fuels and additives

USDA-ARS?s Scientific Manuscript database

Modern diesel engines rely on the fuel itself to lubricate moving parts in the fuel and engine systems. Prior to the late 1990s, diesel fuel from petroleum provided sufficient lubricity to effectively reduce wear in injectors and fuel pumps. Increasingly stringent limitations on the sulfur content o...

33 CFR 245.15 - Delegation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Delegation. 245.15 Section 245.15 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.15 Delegation. District Engineers may undertake removal without prior...

33 CFR 245.15 - Delegation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Delegation. 245.15 Section 245.15 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.15 Delegation. District Engineers may undertake removal without prior...

Prediction and Estimation of Scaffold Strength with different pore size

NASA Astrophysics Data System (ADS)

Muthu, P.; Mishra, Shubhanvit; Sri Sai Shilpa, R.; Veerendranath, B.; Latha, S.

2018-04-01

This paper emphasizes the significance of prediction and estimation of the mechanical strength of 3D functional scaffolds before the manufacturing process. Prior evaluation of the mechanical strength and structural properties of the scaffold will reduce the cost fabrication and in fact ease up the designing process. Detailed analysis and investigation of various mechanical properties including shear stress equivalence have helped to estimate the effect of porosity and pore size on the functionality of the scaffold. The influence of variation in porosity was examined by computational approach via finite element analysis (FEA) and ANSYS application software. The results designate the adequate perspective of the evolutionary method for the regulation and optimization of the intricate engineering design process.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, Faustin Wirkus; Khaire, Trupti S.; Novosad, Valentyn

We present "scraps" (SuperConducting Analysis and Plotting Software), a Python package designed to aid in the analysis and visualization of large amounts of superconducting resonator data, specifically complex transmission as a function of frequency, acquired at many different temperatures and driving powers. The package includes a least-squares fitting engine as well as a Monte-Carlo Markov Chain sampler for sampling the posterior distribution given priors, marginalizing over nuisance parameters, and estimating covariances. A set of plotting tools for generating publication-quality figures is also provided in the package. Lastly, we discuss the functionality of the software and provide some examples of itsmore » utility on data collected from a niobium-nitride coplanar waveguide resonator fabricated at Argonne National Laboratory.« less

Saturn Apollo Program

NASA Image and Video Library

1965-08-01

Two workers are dwarfed by the five J-2 engines of the Saturn V second stage (S-II) as they make final inspections prior to a static test firing by North American Space Division. These five hydrogen -fueled engines produced one million pounds of thrust, and placed the Apollo spacecraft into earth orbit before departing for the moon. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

A New, Highly Improved Two-Cycle Engine

NASA Technical Reports Server (NTRS)

Wiesen, Bernard

2008-01-01

The figure presents a cross-sectional view of a supercharged, variable-compression, two-cycle, internal-combustion engine that offers significant advantages over prior such engines. The improvements are embodied in a combination of design changes that contribute synergistically to improvements in performance and economy. Although the combination of design changes and the principles underlying them are complex, one of the main effects of the changes on the overall engine design is reduced (relative to prior two-cycle designs) mechanical complexity, which translates directly to reduced manufacturing cost and increased reliability. Other benefits include increases in the efficiency of both scavenging and supercharging. The improvements retain the simplicity and other advantages of two-cycle engines while affording increases in volumetric efficiency and performance across a wide range of operating conditions that, heretofore have been accessible to four-cycle engines but not to conventionally scavenged two-cycle ones, thereby increasing the range of usefulness of the two-cycle engine into all areas now dominated by the four-cycle engine. The design changes and benefits are too numerous to describe here in detail, but it is possible to summarize the major improvements: Reciprocating Shuttle Inlet Valve The entire reciprocating shuttle inlet valve and its operating gear is constructed as a single member. The shuttle valve is actuated in a lost-motion arrangement in which, at the ends of its stroke, projections on the shuttle valve come to rest against abutments at the ends of grooves in a piston skirt. This shuttle-valve design obviates the customary complex valve mechanism, actuated from an engine crankshaft or camshaft, yet it is effective with every type of two-cycle engine, from small high-speed single cylinder model engines, to large low-speed multiple cylinder engines.

Astronaut Thermal Exposure: Re-Entry After Low Earth Orbit Rescue Mission

NASA Technical Reports Server (NTRS)

Gillis, David B.; Hamilton, Douglas; Ilcus, Stana; Stepaniak, Phil; Son, Chang; Bue, Grant

2009-01-01

The STS-125 mission, launched May 11, 2009, is the final servicing mission to the Hubble Space Telescope. The repair mission's EVA tasks are described, including: installing a new wide field camera; installing the Cosmic Origins Spectrograph; repairing the Space Telescope Imaging Spectrograph; installing a new outer blanket layer; adding a Soft Capture and Rendezvous System for eventual controlled deorbit in about 2014; replacing the 'A' side Science Instrument Command and Data Handling module; repairing the Advanced Camera for surveys; and, replacing the rate sensor unit gyroscopes, fine guidance sensors and 3 batteries. Additionally, the Shuttle crew cabin thermal environment is described. A CFD model of per person CO2 demonstrates a discrepancy between crew breathing volume and general mid-deck levels of CO2. A follow-on CFD analysis of the mid-deck temperature distribution is provided. Procedural and engineering mitigation plans are presented to counteract thermal exposure upon reentry to the Earth atmosphere. Some of the procedures include: full cold soak the night prior to deorbit; modifying deck stowage to reduce interference with air flow; and early securing of avionics post-landing to reduce cabin thermal load prior to hatch opening. Engineering mitigation activities include modifying the location of the aft starboard ICUs, eliminating the X3 stack and eliminating ICU exhaust air directed onto astronauts; improved engineering data of ICU performance; and, verifying the adequacy of mid-deck temperature control using CFD models in addition to lumped parameter models. Post-mitigation CFD models of mid-deck temperature profiles and distribution are provided.

Bayesian decision analysis as a tool for defining monitoring needs in the field of effects of CSOs on receiving waters.

PubMed

Korving, H; Clemens, F

2002-01-01

In recent years, decision analysis has become an important technique in many disciplines. It provides a methodology for rational decision-making allowing for uncertainties in the outcome of several possible actions to be undertaken. An example in urban drainage is the situation in which an engineer has to decide upon a major reconstruction of a system in order to prevent pollution of receiving waters due to CSOs. This paper describes the possibilities of Bayesian decision-making in urban drainage. In particular, the utility of monitoring prior to deciding on the reconstruction of a sewer system to reduce CSO emissions is studied. Our concern is with deciding whether a price should be paid for new information and which source of information is the best choice given the expected uncertainties in the outcome. The influence of specific uncertainties (sewer system data and model parameters) on the probability of CSO volumes is shown to be significant. Using Bayes' rule, to combine prior impressions with new observations, reduces the risks linked with the planning of sewer system reconstructions.

Hybrid Mobile Communication Networks for Planetary Exploration

NASA Technical Reports Server (NTRS)

Alena, Richard; Lee, Charles; Walker, Edward; Osenfort, John; Stone, Thom

2007-01-01

A paper discusses the continuing work of the Mobile Exploration System Project, which has been performing studies toward the design of hybrid communication networks for future exploratory missions to remote planets. A typical network could include stationary radio transceivers on a remote planet, mobile radio transceivers carried by humans and robots on the planet, terrestrial units connected via the Internet to an interplanetary communication system, and radio relay transceivers aboard spacecraft in orbit about the planet. Prior studies have included tests on prototypes of these networks deployed in Arctic and desert regions chosen to approximate environmental conditions on Mars. Starting from the findings of the prior studies, the paper discusses methods of analysis, design, and testing of the hybrid communication networks. It identifies key radio-frequency (RF) and network engineering issues. Notable among these issues is the study of wireless LAN throughput loss due to repeater use, RF signal strength, and network latency variations. Another major issue is that of using RF-link analysis to ensure adequate link margin in the face of statistical variations in signal strengths.

Video-Game-Like Engine for Depicting Spacecraft Trajectories

NASA Technical Reports Server (NTRS)

Upchurch, Paul R.

2009-01-01

GoView is a video-game-like software engine, written in the C and C++ computing languages, that enables real-time, three-dimensional (3D)-appearing visual representation of spacecraft and trajectories (1) from any perspective; (2) at any spatial scale from spacecraft to Solar-system dimensions; (3) in user-selectable time scales; (4) in the past, present, and/or future; (5) with varying speeds; and (6) forward or backward in time. GoView constructs an interactive 3D world by use of spacecraft-mission data from pre-existing engineering software tools. GoView can also be used to produce distributable application programs for depicting NASA orbital missions on personal computers running the Windows XP, Mac OsX, and Linux operating systems. GoView enables seamless rendering of Cartesian coordinate spaces with programmable graphics hardware, whereas prior programs for depicting spacecraft trajectories variously require non-Cartesian coordinates and/or are not compatible with programmable hardware. GoView incorporates an algorithm for nonlinear interpolation between arbitrary reference frames, whereas the prior programs are restricted to special classes of inertial and non-inertial reference frames. Finally, whereas the prior programs present complex user interfaces requiring hours of training, the GoView interface provides guidance, enabling use without any training.

An Update of the Nation's Long-Term Strategic Needs for NASA's Aeronautics Test Facilities

NASA Technical Reports Server (NTRS)

Anton, Philip S.; Raman, Raj; Osburg, Jan; Kallimani, James G.

2009-01-01

The National Aeronautics and Space Administration's (NASA's) major wind tunnel (WT), propulsion test (PT), and simulation facilities exist to serve NASA's and the nation's aeronautics needs. RAND Corporation researchers conducted a prior study of these facilities from 2002 to 2003, identifying (1) NASA's continuing ability to serve national needs, (2) which facilities appear strategically important from an engineering perspective given the vehicle classes the nation investigates and produces, and (3) management challenges and issues. This documented briefing (DB) is the final report from a new, one-year study (conducted from September 2006 through January 2008), partially updating the prior assessment. The study focuses on updating the list of facilities in the prior study that were deemed to be strategically important (again, from an engineering perspective) in serving those needs. This update also adds a new assessment of national needs for six major aeronautics simulators at NASA and lists those deemed strategically important.

49 CFR 240.115 - Criteria for consideration of prior safety conduct as a motor vehicle operator.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Criteria for consideration of prior safety conduct as a motor vehicle operator. 240.115 Section 240.115 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION QUALIFICATION AND CERTIFICATION OF LOCOMOTIVE ENGINEERS...

49 CFR 240.115 - Criteria for consideration of prior safety conduct as a motor vehicle operator.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Criteria for consideration of prior safety conduct as a motor vehicle operator. 240.115 Section 240.115 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION QUALIFICATION AND CERTIFICATION OF LOCOMOTIVE ENGINEERS...

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

Expedition 23 Flight Engineer Tracy Caldwell Dyson talks with family and colleagues from behind glass prior to her launch onboard a Soyuz rocket with Soyuz Commander Alexander Skvortsov and Flight Engineer Mikhail Kornienko of Russia to the International Space Station (ISS), Friday April 2, 2010 in Baikonur, Kazakhstan. Photo Credit: (NASA/Carla Cioffi)

40 CFR 86.327-79 - Quench checks; NOX analyzer.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for New Gasoline-Fueled and Diesel-Fueled Heavy-Duty Engines; Gaseous Exhaust Test Procedures § 86.327-79..., recalibrate and repeat the quench check. (4) Prior to testing, the difference between the calculated NOX...

40 CFR 86.327-79 - Quench checks; NOX analyzer.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for New Gasoline-Fueled and Diesel-Fueled Heavy-Duty Engines; Gaseous Exhaust Test Procedures § 86.327-79..., recalibrate and repeat the quench check. (4) Prior to testing, the difference between the calculated NOX...

Engineering Objects for Collaboration: Strategies of Ambiguity and Clarity at Knowledge Boundaries

ERIC Educational Resources Information Center

Barley, William C.; Leonardi, Paul M.; Bailey, Diane E.

2012-01-01

Prior research suggests that boundary objects gain meaning through group interaction. Drawing from the literature on strategic ambiguity, we explore the possibility that individuals strategically create potential boundary objects in an attempt to shape the meanings that groups develop. From ethnographic observations of automotive engineers, we…

40 CFR 89.322 - Carbon dioxide analyzer calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Test Equipment Provisions § 89.322 Carbon dioxide analyzer calibration. (a) Prior to its introduction... requirements of paragraph (a)(3) of this section. Proceed as follows: (1) Follow good engineering practices for... engineering practice. For each range calibrated, if the deviation from a least-squares best-fit straight line...

Reliability and Maintainability Analysis for the Amine Swingbed Carbon Dioxide Removal System

NASA Technical Reports Server (NTRS)

Dunbar, Tyler

2016-01-01

I have performed a reliability & maintainability analysis for the Amine Swingbed payload system. The Amine Swingbed is a carbon dioxide removal technology that has gone through 2,400 hours of International Space Station on-orbit use between 2013 and 2016. While the Amine Swingbed is currently an experimental payload system, the Amine Swingbed may be converted to system hardware. If the Amine Swingbed becomes system hardware, it will supplement the Carbon Dioxide Removal Assembly (CDRA) as the primary CO2 removal technology on the International Space Station. NASA is also considering using the Amine Swingbed as the primary carbon dioxide removal technology for future extravehicular mobility units and for the Orion, which will be used for the Asteroid Redirect and Journey to Mars missions. The qualitative component of the reliability and maintainability analysis is a Failure Modes and Effects Analysis (FMEA). In the FMEA, I have investigated how individual components in the Amine Swingbed may fail, and what the worst case scenario is should a failure occur. The significant failure effects are the loss of ability to remove carbon dioxide, the formation of ammonia due to chemical degradation of the amine, and loss of atmosphere because the Amine Swingbed uses the vacuum of space to regenerate the Amine Swingbed. In the quantitative component of the reliability and maintainability analysis, I have assumed a constant failure rate for both electronic and nonelectronic parts. Using this data, I have created a Poisson distribution to predict the failure rate of the Amine Swingbed as a whole. I have determined a mean time to failure for the Amine Swingbed to be approximately 1,400 hours. The observed mean time to failure for the system is between 600 and 1,200 hours. This range includes initial testing of the Amine Swingbed, as well as software faults that are understood to be non-critical. If many of the commercial parts were switched to military-grade parts, the expected mean time to failure would be 2,300 hours. Both calculated mean times to failure for the Amine Swingbed use conservative failure rate models. The observed mean time to failure for CDRA is 2,500 hours. Working on this project and for NASA in general has helped me gain insight into current aeronautics missions, reliability engineering, circuit analysis, and different cultures. Prior my internship, I did not have a lot knowledge about the work being performed at NASA. As a chemical engineer, I had not really considered working for NASA as a career path. By engaging in interactions with civil servants, contractors, and other interns, I have learned a great deal about modern challenges that NASA is addressing. My work has helped me develop a knowledge base in safety and reliability that would be difficult to find elsewhere. Prior to this internship, I had not thought about reliability engineering. Now, I have gained a skillset in performing reliability analyses, and understanding the inner workings of a large mechanical system. I have also gained experience in understanding how electrical systems work while I was analyzing the electrical components of the Amine Swingbed. I did not expect to be exposed to as many different cultures as I have while working at NASA. I am referring to both within NASA and the Houston area. NASA employs individuals with a broad range of backgrounds. It has been great to learn from individuals who have highly diverse experiences and outlooks on the world. In the Houston area, I have come across individuals from different parts of the world. Interacting with such a high number of individuals with significantly different backgrounds has helped me to grow as a person in ways that I did not expect. My time at NASA has opened a window into the field of aeronautics. After earning a bachelor's degree in chemical engineering, I plan to go to graduate school for a PhD in engineering. Prior to coming to NASA, I was not aware of the graduate Pathways program. I intend to apply for the graduate Pathways program as positions are opened up. I would like to pursue future opportunities with NASA, especially as my engineering career progresses.

Teaching Engineering Practices

NASA Astrophysics Data System (ADS)

Cunningham, Christine M.; Carlsen, William S.

2014-03-01

Engineering is featured prominently in the Next Generation Science Standards (NGSS) and related reform documents, but how its nature and methods are described is problematic. This paper is a systematic review and critique of that representation, and proposes that the disciplinary core ideas of engineering (as described in the NGSS) can be disregarded safely if the practices of engineering are better articulated and modeled through student engagement in engineering projects. A clearer distinction between science and engineering practices is outlined, and prior research is described that suggests that precollege engineering design can strengthen children's understandings about scientific concepts. However, a piecemeal approach to teaching engineering practices is unlikely to result in students understanding engineering as a discipline. The implications for science teacher education are supplemented with lessons learned from a number of engineering education professional development projects.

Adaptive Heat Engine.

PubMed

Allahverdyan, A E; Babajanyan, S G; Martirosyan, N H; Melkikh, A V

2016-07-15

A major limitation of many heat engines is that their functioning demands on-line control and/or an external fitting between the environmental parameters (e.g., temperatures of thermal baths) and internal parameters of the engine. We study a model for an adaptive heat engine, where-due to feedback from the functional part-the engine's structure adapts to given thermal baths. Hence, no on-line control and no external fitting are needed. The engine can employ unknown resources; it can also adapt to results of its own functioning that make the bath temperatures closer. We determine resources of adaptation and relate them to the prior information available about the environment.

Application of real-time engine simulations to the development of propulsion system controls

NASA Technical Reports Server (NTRS)

Szuch, J. R.

1975-01-01

The development of digital controls for turbojet and turbofan engines is presented by the use of real-time computer simulations of the engines. The engine simulation provides a test-bed for evaluating new control laws and for checking and debugging control software and hardware prior to engine testing. The development and use of real-time, hybrid computer simulations of the Pratt and Whitney TF30-P-3 and F100-PW-100 augmented turbofans are described in support of a number of controls research programs at the Lewis Research Center. The role of engine simulations in solving the propulsion systems integration problem is also discussed.

scraps: An open-source Python-based analysis package for analyzing and plotting superconducting resonator data

DOE PAGES

Carter, Faustin Wirkus; Khaire, Trupti S.; Novosad, Valentyn; ...

2016-11-07

We present "scraps" (SuperConducting Analysis and Plotting Software), a Python package designed to aid in the analysis and visualization of large amounts of superconducting resonator data, specifically complex transmission as a function of frequency, acquired at many different temperatures and driving powers. The package includes a least-squares fitting engine as well as a Monte-Carlo Markov Chain sampler for sampling the posterior distribution given priors, marginalizing over nuisance parameters, and estimating covariances. A set of plotting tools for generating publication-quality figures is also provided in the package. Lastly, we discuss the functionality of the software and provide some examples of itsmore » utility on data collected from a niobium-nitride coplanar waveguide resonator fabricated at Argonne National Laboratory.« less

List based prefetch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boyle, Peter; Christ, Norman; Gara, Alan

A list prefetch engine improves a performance of a parallel computing system. The list prefetch engine receives a current cache miss address. The list prefetch engine evaluates whether the current cache miss address is valid. If the current cache miss address is valid, the list prefetch engine compares the current cache miss address and a list address. A list address represents an address in a list. A list describes an arbitrary sequence of prior cache miss addresses. The prefetch engine prefetches data according to the list, if there is a match between the current cache miss address and the listmore » address.« less

List based prefetch

DOEpatents

Boyle, Peter [Edinburgh, GB; Christ, Norman [Irvington, NY; Gara, Alan [Yorktown Heights, NY; Kim,; Changhoan, [San Jose, CA; Mawhinney, Robert [New York, NY; Ohmacht, Martin [Yorktown Heights, NY; Sugavanam, Krishnan [Yorktown Heights, NY

2012-08-28

A list prefetch engine improves a performance of a parallel computing system. The list prefetch engine receives a current cache miss address. The list prefetch engine evaluates whether the current cache miss address is valid. If the current cache miss address is valid, the list prefetch engine compares the current cache miss address and a list address. A list address represents an address in a list. A list describes an arbitrary sequence of prior cache miss addresses. The prefetch engine prefetches data according to the list, if there is a match between the current cache miss address and the list address.

I-Wire Heart-on-a-Chip II: Biomechanical analysis of contractile, three-dimensional cardiomyocyte tissue constructs.

PubMed

Schroer, Alison K; Shotwell, Matthew S; Sidorov, Veniamin Y; Wikswo, John P; Merryman, W David

2017-01-15

This companion study presents the biomechanical analysis of the "I-Wire" platform using a modified Hill model of muscle mechanics that allows for further characterization of construct function and response to perturbation. The I-Wire engineered cardiac tissue construct (ECTC) is a novel experimental platform to investigate cardiac cell mechanics during auxotonic contraction. Whereas passive biomaterials often exhibit nonlinear and dissipative behavior, active tissue equivalents, such as ECTCs, also expend metabolic energy to perform mechanical work that presents additional challenges in quantifying their properties. The I-Wire model uses the passive mechanical response to increasing applied tension to measure the inherent stress and resistance to stretch of the construct before, during, and after treatments. Both blebbistatin and isoproterenol reduced prestress and construct stiffness; however, blebbistatin treatment abolished subsequent force-generating potential while isoproterenol enhanced this property. We demonstrate that the described model can replicate the response of these constructs to intrinsic changes in force-generating potential in response to both increasing frequency of stimulation and decreasing starting length. This analysis provides a useful mathematical model of the I-Wire platform, increases the number of parameters that can be derived from the device, and serves as a demonstration of quantitative characterization of nonlinear, active biomaterials. We anticipate that this quantitative analysis of I-Wire constructs will prove useful for qualifying patient-specific cardiomyocytes and fibroblasts prior to their utilization for cardiac regenerative medicine. Passive biomaterials may have non-linear elasticity and losses, but engineered muscle tissue also exhibits time- and force-dependent contractions. Historically, mathematical muscle models include series-elastic, parallel-elastic, contractile, and viscous elements. While hearts-on-a-chip can demonstrate in vitro the contractile properties of engineered cardiac constructs and their response to drugs, most of these use cellular monolayers that cannot be readily probed with controlled forces. The I-Wire platform described in the preceding paper by Sidorov et al. addresses these limitations with three-dimensional tissue constructs to which controlled forces can be applied. In this companion paper, we show how to characterize I-Wire constructs using a non-linear, active Hill model, which should be useful for qualifying cells prior to their use in cardiac regenerative medicine. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Noise source separation of diesel engine by combining binaural sound localization method and blind source separation method

NASA Astrophysics Data System (ADS)

Yao, Jiachi; Xiang, Yang; Qian, Sichong; Li, Shengyang; Wu, Shaowei

2017-11-01

In order to separate and identify the combustion noise and the piston slap noise of a diesel engine, a noise source separation and identification method that combines a binaural sound localization method and blind source separation method is proposed. During a diesel engine noise and vibration test, because a diesel engine has many complex noise sources, a lead covering method was carried out on a diesel engine to isolate other interference noise from the No. 1-5 cylinders. Only the No. 6 cylinder parts were left bare. Two microphones that simulated the human ears were utilized to measure the radiated noise signals 1 m away from the diesel engine. First, a binaural sound localization method was adopted to separate the noise sources that are in different places. Then, for noise sources that are in the same place, a blind source separation method is utilized to further separate and identify the noise sources. Finally, a coherence function method, continuous wavelet time-frequency analysis method, and prior knowledge of the diesel engine are combined to further identify the separation results. The results show that the proposed method can effectively separate and identify the combustion noise and the piston slap noise of a diesel engine. The frequency of the combustion noise and the piston slap noise are respectively concentrated at 4350 Hz and 1988 Hz. Compared with the blind source separation method, the proposed method has superior separation and identification effects, and the separation results have fewer interference components from other noise.

Flight Operations Analysis Tool

NASA Technical Reports Server (NTRS)

Easter, Robert; Herrell, Linda; Pomphrey, Richard; Chase, James; Wertz Chen, Julie; Smith, Jeffrey; Carter, Rebecca

2006-01-01

Flight Operations Analysis Tool (FLOAT) is a computer program that partly automates the process of assessing the benefits of planning spacecraft missions to incorporate various combinations of launch vehicles and payloads. Designed primarily for use by an experienced systems engineer, FLOAT makes it possible to perform a preliminary analysis of trade-offs and costs of a proposed mission in days, whereas previously, such an analysis typically lasted months. FLOAT surveys a variety of prior missions by querying data from authoritative NASA sources pertaining to 20 to 30 mission and interface parameters that define space missions. FLOAT provides automated, flexible means for comparing the parameters to determine compatibility or the lack thereof among payloads, spacecraft, and launch vehicles, and for displaying the results of such comparisons. Sparseness, typical of the data available for analysis, does not confound this software. FLOAT effects an iterative process that identifies modifications of parameters that could render compatible an otherwise incompatible mission set.

Brassica carinata as an alternative oil crop for the production of biodiesel in Italy: engine performance and regulated and unregulated exhaust emissions.

PubMed

Cardone, Massimo; Prati, Maria Vittoria; Rocco, Vittorio; Seggiani, Maurizia; Senatore, Adolfo; Vitoloi, Sandra

2002-11-01

A comparison of the performance of Brassica carinata oil-derived biodiesel with a commercial rapeseed oil-derived biodiesel and petroleum diesel fuel is discussed as regards engine performance and regulated and unregulated exhaust emissions. B. carinata is an oil crop that can be cultivated in coastal areas of central-southern Italy, where it is more difficult to achieve the productivity potentials of Brassica napus (by far the most common rapeseed cultivated in continental Europe). Experimental tests were carried out on a turbocharged direct injection passenger car diesel engine fueled with 100% biodiesel. The unregulated exhaust emissions were characterized by determining the SOOT and soluble organic fraction content in the particulate matter, together with analysis of the content and speciation of polycyclic aromatic hydrocarbons, some of which are potentially carcinogenic, and of carbonyl compounds (aldehydes, ketones) that act as ozone precursors. B. carinata and commercial biodiesel behaved similarly as far as engine performance and regulated and unregulated emissions were concerned. When compared with petroleum diesel fuel, the engine test bench analysis did not show any appreciable variation of output engine torque values, while there was a significant difference in specific fuel consumption data at the lowest loads for the biofuels and petroleum diesel fuel. The biofuels were observed to produce higher levels of NOx concentrations and lower levels of PM with respect to the diesel fuel. The engine heat release analysis conducted shows that there is a potential for increased thermal NOx generation when firing biodiesel with no prior modification to the injection timing. It seems that, for both the biofuels, this behavior is caused by an advanced combustion evolution, which is particularly apparent at the higher loads. When compared with petroleum diesel fuel, biodiesel emissions contain less SOOT, and a greater fraction of the particulate was soluble. The analysis and speciation of the soluble organic fraction of biodiesel particulate suggest that the carcinogenic potential of the biodiesel emissions is probably lower than that of petroleum diesel. Its better adaptivity and productivity in clay and sandy-type soils and in semiarid temperate climate and the fact that the performance of its derived biodiesel is quite similar to commercial biodiesel make B. carinata a promising oil crop that could offer the possibility of exploiting the Mediterranean marginal areas for energetic purposes.

Saturn V Second Stage (S-II) Ready for Static Test

NASA Technical Reports Server (NTRS)

1965-01-01

Two workers are dwarfed by the five J-2 engines of the Saturn V second stage (S-II) as they make final inspections prior to a static test firing by North American Space Division. These five hydrogen -fueled engines produced one million pounds of thrust, and placed the Apollo spacecraft into earth orbit before departing for the moon. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams.

40 CFR 86.230-11 - Test sequence: general requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... vehicle interior climate control system shall be operated with the interior heating system on and the air... changes (e.g., engine-off logic, idle speed operation, spark advance changes) and engine control features...) Prior to the first acceleration of the test at T=20 seconds the climate control settings shall be set as...

40 CFR 86.230-11 - Test sequence: general requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... vehicle interior climate control system shall be operated with the interior heating system on and the air... changes (e.g., engine-off logic, idle speed operation, spark advance changes) and engine control features...) Prior to the first acceleration of the test at T=20 seconds the climate control settings shall be set as...

40 CFR 86.230-11 - Test sequence: general requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... vehicle interior climate control system shall be operated with the interior heating system on and the air... changes (e.g., engine-off logic, idle speed operation, spark advance changes) and engine control features...) Prior to the first acceleration of the test at T=20 seconds the climate control settings shall be set as...

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

Expedition 23 Flight Engineer Tracy Caldwell Dyson, left, Expedition 23 Soyuz Commander Alexander Skvortsov and Expedition 23 Flight Engineer Mikhail Kornienko, right, talk with family and colleagues from behind glass prior to their launch onboard a Soyuz rocket to the International Space Station (ISS), Friday, April 2, 2010 in Baikonur, Kazakhstan. Photo Credit: (NASA/Bill Ingalls)

The Role of Exploratory Talk in Classroom Search Engine Tasks

ERIC Educational Resources Information Center

Knight, Simon; Mercer, Neil

2015-01-01

While search engines are commonly used by children to find information, and in classroom-based activities, children are not adept in their information seeking or evaluation of information sources. Prior work has explored such activities in isolated, individual contexts, failing to account for the collaborative, discourse-mediated nature of search…

49 CFR 611.207 - Overall New Starts project ratings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... evaluation. (2) Ratings for individual projects will be developed upon entry into engineering and prior to an FFGA. Additionally, ratings may be updated while a project is in engineering if the project scope and cost have changed materially since the most recent rating was assigned. (c) These ratings will be used...

Licencing and Training Reform in the Australian Aircraft Maintenance Industry

ERIC Educational Resources Information Center

Hampson, Ian; Fraser, Doug

2016-01-01

The training and licencing of aircraft maintenance engineers fulfils a crucial protective function since it is they who perform and supervise aircraft maintenance and certify that planes are safe afterwards. In Australia, prior to training reform, a trades-based system of aircraft maintenance engineer training existed in an orderly relation with…

40 CFR 86.230-11 - Test sequence: general requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... vehicle interior climate control system shall be operated with the interior heating system on and the air... changes (e.g., engine-off logic, idle speed operation, spark advance changes) and engine control features...) Prior to the first acceleration of the test at T=20 seconds the climate control settings shall be set as...

[Research on engine remaining useful life prediction based on oil spectrum analysis and particle filtering].

PubMed

Sun, Lei; Jia, Yun-xian; Cai, Li-ying; Lin, Guo-yu; Zhao, Jin-song

2013-09-01

The spectrometric oil analysis(SOA) is an important technique for machine state monitoring, fault diagnosis and prognosis, and SOA based remaining useful life(RUL) prediction has an advantage of finding out the optimal maintenance strategy for machine system. Because the complexity of machine system, its health state degradation process can't be simply characterized by linear model, while particle filtering(PF) possesses obvious advantages over traditional Kalman filtering for dealing nonlinear and non-Gaussian system, the PF approach was applied to state forecasting by SOA, and the RUL prediction technique based on SOA and PF algorithm is proposed. In the prediction model, according to the estimating result of system's posterior probability, its prior probability distribution is realized, and the multi-step ahead prediction model based on PF algorithm is established. Finally, the practical SOA data of some engine was analyzed and forecasted by the above method, and the forecasting result was compared with that of traditional Kalman filtering method. The result fully shows the superiority and effectivity of the

Fall 2012 Graduate Engineering Internship Summary

NASA Technical Reports Server (NTRS)

Ehrlich, Joshua

2013-01-01

In the fall of 2012, I participated in the National Aeronautics and Space Administration (NASA) Pathways Intern Employment Program at the Kennedy Space Center (KSC) in Florida. This was my second internship opportunity with NASA, a consecutive extension from a summer 2012 internship. During my four-month tenure, I gained valuable knowledge and extensive hands-on experience with payload design and testing as well as composite fabrication for repair design on future space vehicle structures. As a systems engineer, I supported the systems engineering and integration team with the testing of scientific payloads such as the Vegetable Production System (Veggie). Verification and validation (V&V) of the Veggie was carried out prior to qualification testing of the payload, which incorporated a lengthy process of confirming design requirements that were integrated through one or more validatjon methods: inspection, analysis, demonstration, and testing. Additionally, I provided assistance in verifying design requirements outlined in the V&V plan with the requirements outlined by the scientists in the Science Requirements Envelope Document (SRED). The purpose of the SRED was to define experiment requirements intended for the payload to meet and carry out.

Control techniques to improve Space Shuttle solid rocket booster separation

NASA Technical Reports Server (NTRS)

Tomlin, D. D.

1983-01-01

The present Space Shuttle's control system does not prevent the Orbiter's main engines from being in gimbal positions that are adverse to solid rocket booster separation. By eliminating the attitude error and attitude rate feedback just prior to solid rocket booster separation, the detrimental effects of the Orbiter's main engines can be reduced. In addition, if angular acceleration feedback is applied, the gimbal torques produced by the Orbiter's engines can reduce the detrimental effects of the aerodynamic torques. This paper develops these control techniques and compares the separation capability of the developed control systems. Currently with the worst case initial conditions and each Shuttle system dispersion aligned in the worst direction (which is more conservative than will be experienced in flight), the solid rocket booster has an interference with the Shuttle's external tank of 30 in. Elimination of the attitude error and attitude rate feedback reduces that interference to 19 in. Substitution of angular acceleration feedback reduces the interference to 6 in. The two latter interferences can be eliminated by atess conservative analysis techniques, that is, by using a root sum square of the system dispersions.

Characterization of the human plasma phosphoproteome using linear ion trap mass spectrometry and multiple search engines.

PubMed

Carrascal, Montserrat; Gay, Marina; Ovelleiro, David; Casas, Vanessa; Gelpí, Emilio; Abian, Joaquin

2010-02-05

Major plasma protein families play different roles in blood physiology and hemostasis and in immunodefense. Other proteins in plasma can be involved in signaling as chemical messengers or constitute biological markers of the status of distant tissues. In this respect, the plasma phosphoproteome holds potentially relevant information on the mechanisms modulating these processes through the regulation of protein activity. In this work we describe for the first time a collection of phosphopeptides identified in human plasma using immunoaffinity separation of the seven major serum protein families from other plasma proteins, SCX fractionation, and TiO(2) purification prior to LC-MS/MS analysis. One-hundred and twenty-seven phosphosites in 138 phosphopeptides mapping 70 phosphoproteins were identified with FDR < 1%. A high-confidence collection of phosphosites was obtained using a combined search with the OMSSA, SEQUEST, and Phenyx search engines.

Nonlinear Thermoelastic Model for SMAs and SMA Hybrid Composites

NASA Technical Reports Server (NTRS)

Turner, Travis L.

2004-01-01

A constitutive mathematical model has been developed that predicts the nonlinear thermomechanical behaviors of shape-memory-alloys (SMAs) and of shape-memory-alloy hybrid composite (SMAHC) structures, which are composite-material structures that contain embedded SMA actuators. SMAHC structures have been investigated for their potential utility in a variety of applications in which there are requirements for static or dynamic control of the shapes of structures, control of the thermoelastic responses of structures, or control of noise and vibrations. The present model overcomes deficiencies of prior, overly simplistic or qualitative models that have proven ineffective or intractable for engineering of SMAHC structures. The model is sophisticated enough to capture the essential features of the mechanics of SMAHC structures yet simple enough to accommodate input from fundamental engineering measurements and is in a form that is amenable to implementation in general-purpose structural analysis environments.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The primary purpose of this report is to provide an archival record of the activities of the Engineering Physics and Mathematics Division during the period September 1, 1989 through March 31, 1991. Earlier reports in this series are identified on the previous pages, along with the progress reports describing ORNL's research on the mathematical sciences prior to 1984 when those activities moved into the division. As in previous reports, our research is described through abstracts of journal articles, technical reports, and presentations. Summary lists of publications and presentations, staff additions and departures, scientific and professional activities of division staff, andmore » technical conferences organized and sponsored by the division are included as appendices. The report is organized following the division of our research among four sections and information centers. These research areas are: Mathematical Sciences; Nuclear Data Measurement and Evaluations; Intelligent Systems; Nuclear Analysis and Shielding; and Engineering Physics Information Center.« less

Applications of Endothermic Reaction Technology to the High Speed Civil Transport

NASA Technical Reports Server (NTRS)

Glickstein, Marvin R.; Spadaccini, Louis J.

1998-01-01

The success of strategies for controlling emissions and enhancing performance in High Speed Research applications may be Increased by more effective utilization of the heat sink afforded by the fuel in the vehicle thermal management system. This study quantifies the potential benefits associated with the use of supercritical preheating and endothermic cracking of let fuel prior to combustion to enhance the thermal management capabilities of the propulsion systems in the High Speed Civil Transport (HSCT). A fuel-cooled thermal management system, consisting of plate-fin heat exchangers and a small auxiliary compressor, is defined for the HSCT, Integrated with the engine, and an assessment of the effect on engine performance, weight, and operating cost is performed. The analysis indicates significant savings due a projected improvement in fuel economy, and the potential for additional benefit if the cycle is modified to take full advantage of all the heat sink available in the fuel.

Effect of Stagger on the Vibroacoustic Loads from Clustered Rockets

NASA Technical Reports Server (NTRS)

Rojo, Raymundo; Tinney, Charles E.; Ruf, Joseph H.

2016-01-01

The effect of stagger startup on the vibro-acoustic loads that form during the end- effects-regime of clustered rockets is studied using both full-scale (hot-gas) and laboratory scale (cold gas) data. Both configurations comprise three nozzles with thrust optimized parabolic contours that undergo free shock separated flow and restricted shock separated flow as well as an end-effects regime prior to flowing full. Acoustic pressure waveforms recorded at the base of the nozzle clusters are analyzed using various statistical metrics as well as time-frequency analysis. The findings reveal a significant reduction in end- effects-regime loads when engine ignition is staggered. However, regardless of stagger, both the skewness and kurtosis of the acoustic pressure time derivative elevate to the same levels during the end-effects-regime event thereby demonstrating the intermittence and impulsiveness of the acoustic waveforms that form during engine startup.

Interests and attitudes of engineering students

NASA Astrophysics Data System (ADS)

Rutherford, Brian

2007-12-01

Engineering programs have been less successful than other professions in achieving gender equity. Analyses of gender differences in the attitudes and interests of engineering students may help illuminate ways to combat the underrepresentation of women in engineering. This study examined data collected from 863 engineering students who attended 15 American universities from fall 2005 through spring 2006 using an online survey. The survey was designed to understand the backgrounds, academic preparation, motivation, interests, and attitudes of engineering students. To determine whether males and females received different academic preparation prior to entering engineering, the survey examined participants' mathematics, science, and technical coursework taken in high school. The questions probed students' comfort and interest level in mathematics, science, and technology/engineering and investigated student interest in the three fundamental engineering activities by asking 49 design, build, and analyze questions on topics covering a variety of engineering disciplines. A combination of question formats was used including pre-categorized demographic information, 5-point Likert scales, and open-ended responses. Gender similarities and differences were identified and their implications were considered for the recruitment and retention of engineers. Female engineering students in this study were equally or better prepared than males to major in engineering based on the number and types of science and mathematics classes taken in high school. However, statistically significant gender differences were found in the attitudes and interests of engineering students. The difference in the comfort level, interest in learning, being able to demonstrate, or in performing stem skills depended on the question topic rather than gender. The areas with the highest comfort and interest level were often different for females and males. Several topics and curriculum areas of high interest to both genders related to engineering education in several engineering disciplines were identified. It appears that females and males were motivated to choose engineering as a career for different reasons. Analysis revealed that female engineering students are generally more altruistic and less interested in "things" than male engineering students. This study also found that females were comfortable in mathematics or science, but were less comfortable using computers, tools, and machines---all essential engineering skills.

Retaining minorities in engineering: Assessment of a program prototype

NASA Astrophysics Data System (ADS)

Good, Jennifer Marie (Phillips)

Program assessment is an essential part of healthy program development. Assessment should include multiple considerations, dimensions, and outcomes that match the program's objectives. As a newly formed retention program, the Auburn University Minority Engineering Program, designed to help pre-engineering minority students make the transition into their freshman year of university studies, incorporated evaluation and assessment into all three components of the program (the interactive learning laboratory, critical-thinking workshops, and Sunday-evening tutorials) from the program's inception. If students successfully adapted to the university environment and the demands of the pre-engineering course of study, then retention of minority students in the College of Engineering should improve. Data were gathered on the students involved in the various program components. Students who entered the Minority Engineering Program were pre- and posttested on three standardized subtests (critical thinking, mathematics, and science reasoning) of the Collegiate Assessment of Academic Proficiency. The first-quarter grade-point averages of the students were also gathered to compare their grades to freshman students in previous quarters within the College of Engineering. Qualitative data were also gathered on this same group of students. An analysis of the data revealed that student achievement is affected by involvement in the Minority Engineering Program. Specifically, the first quarter grade point averages of students involved in the program exceeded those of their peers in earlier years of study prior to the program's existence. In addition, mathematics and science reasoning scores on standardized tests increased pre- to postintervention. Comments collected in journals and files also demonstrated use of critical-thinking and problem-solving skills employed by the students. Recommendations for alterations of the program were made based on the outcome of the program evaluation. Further suggestions for research in minority engineering program development and evaluation were also discussed.

Health effects of inhaled gasoline engine emissions.

PubMed

McDonald, Jacob D; Reed, Matthew D; Campen, Matthew J; Barrett, Edward G; Seagrave, JeanClare; Mauderly, Joe L

2007-01-01

Despite their prevalence in the environment, and the myriad studies that have shown associations between morbidity or mortality with proximity to roadways (proxy for motor vehicle exposures), relatively little is known about the toxicity of gasoline engine emissions (GEE). We review the studies conducted on GEE to date, and summarize the findings from each of these studies. While there have been several studies, most of the studies were conducted prior to 1980 and thus were not conducted with contemporary engines, fuels, and driving cycles. In addition, many of the biological assays conducted during those studies did not include many of the assays that are conducted on contemporary inhalation exposures to air pollutants, including cardiovascular responses and others. None of the exposures from these earlier studies were characterized at the level of detail that would be considered adequate today. A recent GEE study was conducted as part of the National Environmental Respiratory Center (www.nercenter.org). In this study several in-use mid-mileage General Motors (Chevrolet S-10) vehicles were purchased and utilized for inhalation exposures. An exposure protocol was developed where engines were operated with a repeating California Unified Driving Cycle with one cold start per day. Two separate engines were used to provide two cold starts over a 6-h inhalation period. The exposure atmospheres were characterized in detail, including detailed chemical and physical analysis of the gas, vapor, and particle phase. Multiple rodent biological models were studied, including general toxicity and inflammation (e.g., serum chemistry, lung lavage cell counts/differentials, cytokine/chemokine analysis, histopathology), asthma (adult and in utero exposures with pulmonary function and biochemical analysis), cardiovascular effects (biochemical and electrocardiograph changes in susceptible rodent models), and susceptibility to infection (Pseudomonas bacteria challenge). GEE resulted in significant biological effects for upregulation of MIP-2, clearance of Pseudomonas bacteria, development of allergic response after in utero exposure, and cardiovascular indicators of vasoconstriction, oxidant stress, and damage.

Method for improving the fuel efficiency of a gas turbine engine

NASA Technical Reports Server (NTRS)

Coffinberry, G. A. (Inventor)

1985-01-01

An energy recovery system is provided for an aircraft gas turbine engine of the type in which some of the pneumatic energy developed by the engine is made available to support systems such as an environmental control system. In one such energy recovery system, some of the pneumatic energy made available to but not utilized by the support system is utilized to heat the engine fuel immediately prior to the consumption of the fuel by the engine. Some of the recovered energy may also be utilized to heat the fuel in the fuel tanks. Provision is made for multiengine applications wherein energy recovered from one engine may be utilized by another one of the engines or systems associated therewith.

Apparatus for improving the fuel efficiency of a gas turbine engine

NASA Technical Reports Server (NTRS)

Coffinberry, G. A. (Inventor)

1983-01-01

An energy recovery system is provided for an aircraft gas turbine engine of the type in which some of the pneumatic energy developed by the engine is made available to support systems such as an environmental control system. In one such energy recovery system, some of the pneumatic energy made available to but not utilized by the support system is utilized to heat the engine fuel immediately prior to the consumption of the fuel by the engine. Some of the recovered energy may also be utilized to heat the fuel in the fuel tanks. Provision is made for multiengine applications wherein energy recovered from one engine may be utilized by another one of the engines or systems associated therewith.

Space shuttle main engine controller

NASA Technical Reports Server (NTRS)

Mattox, R. M.; White, J. B.

1981-01-01

A technical description of the space shuttle main engine controller, which provides engine checkout prior to launch, engine control and monitoring during launch, and engine safety and monitoring in orbit, is presented. Each of the major controller subassemblies, the central processing unit, the computer interface electronics, the input electronics, the output electronics, and the power supplies are described and discussed in detail along with engine and orbiter interfaces and operational requirements. The controller represents a unique application of digital concepts, techniques, and technology in monitoring, managing, and controlling a high performance rocket engine propulsion system. The operational requirements placed on the controller, the extremely harsh operating environment to which it is exposed, and the reliability demanded, result in the most complex and rugged digital system ever designed, fabricated, and flown.

Study of solid rocket motor for space shuttle booster, volume 2, book 5, appendices E thru H

NASA Technical Reports Server (NTRS)

1972-01-01

Preliminary parametric studies were performed to establish size, weight and packaging arrangements for aerodynamic decelerator devices that could be used for recovery of the expended solid propellant rocket motors used in the launch phase of the Space Shuttle System. Computations were made using standard engineering analysis techniques. Terminal stage parachutes were sized to provide equilibrium descent velocities for water entry that are presently thought to be acceptable without developing loads that could exceed the boosters structural integrity. The performance characteristics of the aerodynamic parachute decelerator devices considered are based on analysis and prior test results for similar configurations and are assumed to be maintained at the scale requirements of the present problem.

Support and power-plant documentation for the gas-turbine-powered-bus demonstration program. Final report, 1 January 1980-30 September 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nigro, D.N.; Stewart, R.G.; Apple, S.A.

1982-03-01

The operational experience obtained for the GT404-4 gas turbine engines in the Intercity and Intracity Bus Demonstration Programs is described for the period January 1980 through September 1981. Support for the engines and automatic transmissions involved in this program provided engineering and field service, spare parts and tools, training, and factory overhauls. The Greyhound (intercity) coaches accumulated 183,054 mi (294,595 km) and 5154 hr of total operation. The Baltimore Transit (intracity) coaches accumulated 40,567 mi (65,285 km) and 1840 hr of total operation. In service, the turbine-powered Greyhound and Transit coaches achieved approximately 25% and 40% lower fuel mileage, respectively,more » than did the production diesel-powered coaches. The gas turbine engine will require the advanced ceramic development currently being sponsored by the DOE and NASA to achieve fuel economy equivalent not only to that of today's diesel engines but also to the projected fuel economy of the advanced diesel engines of the 1990s. Sufficient experience was not achieved with the coaches prior to the start of service to identify and eliminate many of the problems associated with the startup of new equipment. Because of these problems, the mean miles between incident were unacceptably low. The future gas turbine system should be developed sufficiently to establish satisfactory durability prior to evaluation in revenue service. Commercialization of the gas turbine bus engine remains a viable goal for the future.« less

Support and power plant documentation for the gas turbine powered bus demonstration program

NASA Technical Reports Server (NTRS)

Nigro, D. N.; Stewart, R. G.; Apple, S. A.

1982-01-01

The operational experience obtained for the GT404-4 gas turbine engines in the intercity and intracity Bus Demonstration Programs is described for the period January 1980 through September 1981. Support for the engines and automatic transmissions involved in this program provided engineering and field service, spare parts and tools, training, and factory overhauls. the Greyhound (intercity) coaches accumulated 183,054 mi (294,595 km) and 5154 hr of total operation. The Baltimore Transit (intracity) coaches accumulated 40,567 mi (65,285 km) and 1840 hr of total operation. In service, the turbine powered Greyhound and Transit coaches achieved approximately 25% and 40% lower fuel mileage, respectively, than did the production diesel powered coaches. The gas turbine engine will require the advanced ceramic development currently being sponsored by the DOE and NASA to achieve fuel economy equivalent not only to that of today's diesel engines but also to the projected fuel economy of the advanced diesel engines of the 1990s. Sufficient experience was not achieved with the coaches prior to the start of service to identify and eliminate many of the problems associated with the startup of new equipment. Because of these problems, the mean miles between incident were unacceptably low. The future gas turbine system should be developed sufficiently to establish satisfactory durability prior to evaluation in revenue service. Commercialization of the gas turbine bus engine remains a viable goal for the future.

The Role of NDT in Forensic Engineering

NASA Astrophysics Data System (ADS)

Leon-Salamanca, Teodoro

2007-03-01

Forensic engineering refers to a comprehensive investigation of the root cause of failures in structures and operating equipment, usually dealing with the relation and application of engineering facts to legal problems and product liability. The first and often most critical step is to use NDT to fully define the size, shape, and possible nature of all defects in the failed item prior to performing destructive tests. An example of a case where NDT played a critical role is presented.

Engineering students at typically invisible transition points: A focus on admissions and the sophomore year

NASA Astrophysics Data System (ADS)

Holloway, Elizabeth M.

As of 2012, women are approximately 19% of all engineering undergraduate students nationally (American Society for Engineering Education, 2012). Women's representation in engineering has not changed significantly over the last 20 years, despite increased attention, increased funding, and increased programmatic activities intended to encourage more women to become engineers. Research around the world continues to seek identification of the reasons for the underrepresentation of women in engineering. This prior work has focused primarily on two broad areas: recruiting, that is, preparation, socialization, exposure, and experiences prior to college; and retention, that is, experiences in higher education. Retention studies and programmatic responses to those studies mostly have been confined to the collegiate first year, a time of historically high attrition. Little attention has been paid to the university admissions process, one of the gateways to engineering studies. Little attention also has been paid to the experiences of college sophomores, whose attrition rates approach those of first-year college students. The first section of this dissertation presents a statistical analysis that indicated a bias in favor of men in the admission process. Success factor modeling suggested a different set of admission criteria could mitigate this bias. After recommendations to change admission criteria were implemented, the percent of female enrollment in engineering increased and statistical analysis confirmed that bias was substantially neutralized. The second section of this dissertation presents three frameworks for understanding how sophomores may be defined. The processes of conceptualizing and operationalizing what it means to be a sophomore impact the types of issues that can be investigated about student attrition, the findings that result from those investigations, and the ability to make cross institutional or programmatic comparisons using a clearly stated definition. Three definitions for classifying a sophomore--cohort, credits, and curriculum--are presented. The implications of each are discussed relative to the overall population but also specifically to women. All three retention methodologies were based on continued enrollment, with results disaggregated by gender. When analyzing retention data, the definition of a sophomore is an important choice as different definitions may or seem to provide different results. The cohort framework, for example, showed a higher percentage of students retained to their second year than to their third year. In contrast, a credit framework showed a higher percentage of students moving to a junior classification than to a sophomore classification. Because the literature review indicates that very little work has been done specifically on the sophomore engineer and most discussions about the sophomore year do not clearly state which sophomore framework is being applied to the research, this portion of the dissertation is a much needed step in clarifying the underlying bases whereby claims about retention are made. The third section of this dissertation is a study of sophomores' experiences in the engineering disciplines using the cohort definition of a sophomore. The cohort definition is used in this section to focus on the socio-cultural aspects of the second year in college. With a historical emphasis on and increasing positive results of increasing first-year retention, attention is now turning to the sophomore year. Understanding sophomore students' experiences in engineering may assist in developing strategies to reduce attrition and may assist in managing the culture in such a way that makes it more attractive to women and others who are underrepresented. The Sophomore Experiences Survey (Schreiner, 2010) was administered at one institution to the sophomore engineering cohort. Statistical comparisons of results between engineers and sophomores nationally showed more areas of similarity than differences, although the differences indicated that engineering sophomores were less engaged in their learning and less engaged with faculty and advisors. Sophomore engineering women were much more likely than men to be involved in engineering peer mentoring or leadership programs. Multiple regression analysis indicated that the most significant predictor of student satisfaction was satisfaction with peers on campus. The most significant predictor of intention to persist and intention to graduate was surety of major choice. However, there were differences in the most significant predictors when looking at men and women separately. Predictors of success outcomes for engineering sophomores point to the interconnectedness of experiences with faculty, advisors, and peers with individual student traits, characteristics, and preferences, with individual aspects acting as mediating and moderating factors. The overarching results of this research project offer frameworks through which change in the engineering education process can lead to greater participation by women in the engineering field, and increased retention rates for all engineering students.

Meanline Analysis of Turbines with Choked Flow in the Object-Oriented Turbomachinery Analysis Code

NASA Technical Reports Server (NTRS)

Hendricks, Eric S.

2016-01-01

The prediction of turbomachinery performance characteristics is an important part of the conceptual aircraft engine design process. During this phase, the designer must examine the effects of a large number of turbomachinery design parameters to determine their impact on overall engine performance and weight. The lack of detailed design information available in this phase necessitates the use of simpler meanline and streamline methods to determine the turbomachinery geometry characteristics and provide performance estimates prior to more detailed CFD (Computational Fluid Dynamics) analyses. While a number of analysis codes have been developed for this purpose, most are written in outdated software languages and may be difficult or impossible to apply to new, unconventional designs. The Object-Oriented Turbomachinery Analysis Code (OTAC) is currently being developed at NASA Glenn Research Center to provide a flexible meanline and streamline analysis capability in a modern object-oriented language. During the development and validation of OTAC, a limitation was identified in the code's ability to analyze and converge turbines as the flow approached choking. This paper describes a series of changes which can be made to typical OTAC turbine meanline models to enable the assessment of choked flow up to limit load conditions. Results produced with this revised model setup are provided in the form of turbine performance maps and are compared to published maps.

Stochastic Simulation Tool for Aerospace Structural Analysis

NASA Technical Reports Server (NTRS)

Knight, Norman F.; Moore, David F.

2006-01-01

Stochastic simulation refers to incorporating the effects of design tolerances and uncertainties into the design analysis model and then determining their influence on the design. A high-level evaluation of one such stochastic simulation tool, the MSC.Robust Design tool by MSC.Software Corporation, has been conducted. This stochastic simulation tool provides structural analysts with a tool to interrogate their structural design based on their mathematical description of the design problem using finite element analysis methods. This tool leverages the analyst's prior investment in finite element model development of a particular design. The original finite element model is treated as the baseline structural analysis model for the stochastic simulations that are to be performed. A Monte Carlo approach is used by MSC.Robust Design to determine the effects of scatter in design input variables on response output parameters. The tool was not designed to provide a probabilistic assessment, but to assist engineers in understanding cause and effect. It is driven by a graphical-user interface and retains the engineer-in-the-loop strategy for design evaluation and improvement. The application problem for the evaluation is chosen to be a two-dimensional shell finite element model of a Space Shuttle wing leading-edge panel under re-entry aerodynamic loading. MSC.Robust Design adds value to the analysis effort by rapidly being able to identify design input variables whose variability causes the most influence in response output parameters.

Prior Self-Efficacy Interacts with Experiential Valence to Influence Self-Efficacy among Engineering Students: An Experimental Study

ERIC Educational Resources Information Center

Chang, Yevvon Yi-Chi; Chiou, Wen-Bin

2017-01-01

Self-efficacy toward science learning has been shown to play a crucial role in determining students' motivation and achievements. Social cognitive theory proposes that positive and negative task outcomes affect mastery experiences from which self-efficacy develops. The current research examined whether prior level of self-efficacy would serve as a…

49 CFR Appendix E to Part 222 - Requirements for Wayside Horns

Code of Federal Regulations, 2011 CFR

2011-10-01

..., indicates that the system is not operating as intended; 4. Horn system must provide a minimum sound level of... locomotive engineer to sound the locomotive horn for at least 15 seconds prior to arrival at the crossing in...; 5. Horn system must sound at a minimum of 15 seconds prior to the train's arrival at the crossing...

49 CFR Appendix E to Part 222 - Requirements for Wayside Horns

Code of Federal Regulations, 2010 CFR

2010-10-01

..., indicates that the system is not operating as intended; 4. Horn system must provide a minimum sound level of... locomotive engineer to sound the locomotive horn for at least 15 seconds prior to arrival at the crossing in...; 5. Horn system must sound at a minimum of 15 seconds prior to the train's arrival at the crossing...

Development and tuning of an original search engine for patent libraries in medicinal chemistry.

PubMed

Pasche, Emilie; Gobeill, Julien; Kreim, Olivier; Oezdemir-Zaech, Fatma; Vachon, Therese; Lovis, Christian; Ruch, Patrick

2014-01-01

The large increase in the size of patent collections has led to the need of efficient search strategies. But the development of advanced text-mining applications dedicated to patents of the biomedical field remains rare, in particular to address the needs of the pharmaceutical & biotech industry, which intensively uses patent libraries for competitive intelligence and drug development. We describe here the development of an advanced retrieval engine to search information in patent collections in the field of medicinal chemistry. We investigate and combine different strategies and evaluate their respective impact on the performance of the search engine applied to various search tasks, which covers the putatively most frequent search behaviours of intellectual property officers in medical chemistry: 1) a prior art search task; 2) a technical survey task; and 3) a variant of the technical survey task, sometimes called known-item search task, where a single patent is targeted. The optimal tuning of our engine resulted in a top-precision of 6.76% for the prior art search task, 23.28% for the technical survey task and 46.02% for the variant of the technical survey task. We observed that co-citation boosting was an appropriate strategy to improve prior art search tasks, while IPC classification of queries was improving retrieval effectiveness for technical survey tasks. Surprisingly, the use of the full body of the patent was always detrimental for search effectiveness. It was also observed that normalizing biomedical entities using curated dictionaries had simply no impact on the search tasks we evaluate. The search engine was finally implemented as a web-application within Novartis Pharma. The application is briefly described in the report. We have presented the development of a search engine dedicated to patent search, based on state of the art methods applied to patent corpora. We have shown that a proper tuning of the system to adapt to the various search tasks clearly increases the effectiveness of the system. We conclude that different search tasks demand different information retrieval engines' settings in order to yield optimal end-user retrieval.

Development and tuning of an original search engine for patent libraries in medicinal chemistry

PubMed Central

2014-01-01

Background The large increase in the size of patent collections has led to the need of efficient search strategies. But the development of advanced text-mining applications dedicated to patents of the biomedical field remains rare, in particular to address the needs of the pharmaceutical & biotech industry, which intensively uses patent libraries for competitive intelligence and drug development. Methods We describe here the development of an advanced retrieval engine to search information in patent collections in the field of medicinal chemistry. We investigate and combine different strategies and evaluate their respective impact on the performance of the search engine applied to various search tasks, which covers the putatively most frequent search behaviours of intellectual property officers in medical chemistry: 1) a prior art search task; 2) a technical survey task; and 3) a variant of the technical survey task, sometimes called known-item search task, where a single patent is targeted. Results The optimal tuning of our engine resulted in a top-precision of 6.76% for the prior art search task, 23.28% for the technical survey task and 46.02% for the variant of the technical survey task. We observed that co-citation boosting was an appropriate strategy to improve prior art search tasks, while IPC classification of queries was improving retrieval effectiveness for technical survey tasks. Surprisingly, the use of the full body of the patent was always detrimental for search effectiveness. It was also observed that normalizing biomedical entities using curated dictionaries had simply no impact on the search tasks we evaluate. The search engine was finally implemented as a web-application within Novartis Pharma. The application is briefly described in the report. Conclusions We have presented the development of a search engine dedicated to patent search, based on state of the art methods applied to patent corpora. We have shown that a proper tuning of the system to adapt to the various search tasks clearly increases the effectiveness of the system. We conclude that different search tasks demand different information retrieval engines' settings in order to yield optimal end-user retrieval. PMID:24564220

Transparent superstrate terrestrial solar cell module

NASA Technical Reports Server (NTRS)

1977-01-01

The design, development, fabrication, and testing of the transparent solar cell module were examined. Cell performance and material process characteristics were determined by extensive tests and design modifications were made prior to preproduction fabrication. These tests included three cell submodules and two full size engineering modules. Along with hardware and test activity, engineering documentation was prepared and submitted.

The Use of Reverse Engineering to Analyse Student Computer Programs.

ERIC Educational Resources Information Center

Vanneste, Philip; And Others

1996-01-01

Discusses how the reverse engineering approach can generate feedback on computer programs without the user having any prior knowledge of what the program was designed to do. This approach uses the cognitive model of programming knowledge to interpret both context independent and dependent errors in the same words and concepts as human programmers.…

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

The Soyuz TMA-18 spacecraft is seen at sunrise prior to its launch at 10:04am, Friday, April 2, 2010 in Baikonur, Kazakhstan. The Soyuz spacecraft will carry Expedition 23 Soyuz Commander Alexander Skvortsov of Russia, Flight Engineer Mikhail Kornienko of Russia, and NASA Flight Engineer Tracy Caldwell Dyson to the International Space Station. Photo Credit: (NASA/Bill Ingalls)

Entry and Persistence of Women and Minorities in College Science and Engineering Education. Research and Development Report. NCES 2000-601

ERIC Educational Resources Information Center

Huang, Gary; Taddese, Nebiyu; Walter, Elizabeth

2000-01-01

This study examines the gaps related to gender and race/ethnicity in entrance, persistence, and attainment of postsecondary science and engineering (S&E) education. After reviewing selected prior research and examining potentially relevant variables in two National Center for Education Statistics (NCES) surveys, several variables were selected…

An application of tensor ideas to nonlinear modeling of a turbofan jet engine

NASA Technical Reports Server (NTRS)

Klingler, T. A.; Yurkovich, S.; Sain, M. K.

1982-01-01

An application of tensor modelling to a digital simulation of NASA's Quiet, Clean, Shorthaul Experimental (QCSE) gas turbine engine is presented. The results show that the tensor algebra offers a universal parametrization which is helpful in conceptualization and identification for plant modelling prior to feedback or for representing scheduled controllers over an operating line.

77 FR 44429 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

... not be fuel resistant, which could lead to detachment of particles from the fuel hose and cause..., if not corrected, could lead to detachment of particles from the fuel hose and irregularities in the... waiving notice and comment prior to adoption of this rule because detachment of particles from the fuel...

Students' Attitudes towards Group-Based Project Exams in Two Engineering Programmes

ERIC Educational Resources Information Center

Dahl, Bettina; Kolmos, Anette

2015-01-01

At Aalborg University, engineering students spend half the time each semester in groups working on projects in a problem-based learning (PBL) curriculum. The projects are assessed through group exams, except for between 2007 and 2013 when the law forbade group-based project exams. Prior to 2007, a survey showed that students preferred the…

Investigating and Developing Engineering Students' Mathematical Modelling and Problem-Solving Skills

ERIC Educational Resources Information Center

Wedelin, Dag; Adawi, Tom; Jahan, Tabassum; Andersson, Sven

2015-01-01

How do engineering students approach mathematical modelling problems and how can they learn to deal with such problems? In the context of a course in mathematical modelling and problem solving, and using a qualitative case study approach, we found that the students had little prior experience of mathematical modelling. They were also inexperienced…

Multi-fuel rotary engine for general aviation aircraft

NASA Technical Reports Server (NTRS)

Jones, C.; Ellis, D. R.; Meng, P. R.

1983-01-01

Design studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, on advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at 7620 (25000 m/ft) altitude. A follow on study extended the results to larger (2500 hp max.) engine sizes suitable for applications such as commuter transports and helicopters. The study engine designs were derived from relevant engine development background including both prior and recent engine test results using direct injected unthrottled rotary engine technology. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 27 to 33 percent fuel economy improvement for the rotary engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

Increased urinary excretion of 8-hydroxydeoxyguanosine in engine room personnel exposed to polycyclic aromatic hydrocarbons

PubMed Central

Nilsson, R; Nordlinder, R; Moen, B; Ovrebo, S; Bleie, K; Skorve, A; Hollund, B; Tagesson, C

2004-01-01

Background: Previous investigations indicate that engine room personnel on ships are exposed to polycyclic aromatic hydrocarbons (PAH) from oil and oil products, with dermal uptake as the major route of exposure. Several PAH are known carcinogens and mutagens. Aims: To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxy-guanosine (8OHdG), in engine room personnel, and to study the association between 8OHdG and 1-hydroxypyrene (1OHP), a biological marker for PAH exposure. Methods: Urine samples were collected from engine room personnel (n = 36) on 10 Swedish and Norwegian ships and from unexposed controls (n = 34) with similar age and smoking habits. The exposure to oils, engine exhaust, and tobacco smoke 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8OHdG and 1OHP by high performance liquid chromatography. Results: Excretion in urine of 8OHdG (adjusted to density 1.022) was similar for controls (mean 18.0 nmol/l, n = 33), and for those who had been in the engine room without skin contact with oils (mean 18.7 nmol/l, n = 15). Engine room personnel who reported skin contact with oil had increased excretion of 8OHdG (mean 23.2 nmol/l, n = 19). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1OHP and ln 8OHdG were significantly correlated, and the association was still highly significant when the effects of smoking and age were accounted for in a multiple regression analysis. Conclusion: Results indicate that exposure to PAH or possibly other compounds from skin contact with oils in engine rooms may cause oxidative DNA damage. PMID:15258276

Increased urinary excretion of 8-hydroxydeoxyguanosine in engine room personnel exposed to polycyclic aromatic hydrocarbons.

PubMed

Nilsson, R; Nordlinder, R; Moen, B E; Øvrebø, S; Bleie, K; Skorve, A H; Hollund, B E; Tagesson, C

2004-08-01

Previous investigations indicate that engine room personnel on ships are exposed to polycyclic aromatic hydrocarbons (PAH) from oil and oil products, with dermal uptake as the major route of exposure. Several PAH are known carcinogens and mutagens. To investigate the urinary excretion of a marker for oxidative DNA damage, 8-hydroxydeoxy-guanosine (8OHdG), in engine room personnel, and to study the association between 8OHdG and 1-hydroxypyrene (1OHP), a biological marker for PAH exposure. Urine samples were collected from engine room personnel (n = 36) on 10 Swedish and Norwegian ships and from unexposed controls (n = 34) with similar age and smoking habits. The exposure to oils, engine exhaust, and tobacco smoke 24 hours prior to sampling was estimated from questionnaires. The urinary samples were frozen for later analyses of 8OHdG and 1OHP by high performance liquid chromatography. Excretion in urine of 8OHdG (adjusted to density 1.022) was similar for controls (mean 18.0 nmol/l, n = 33), and for those who had been in the engine room without skin contact with oils (mean 18.7 nmol/l, n = 15). Engine room personnel who reported skin contact with oil had increased excretion of 8OHdG (mean 23.2 nmol/l, n = 19). The difference between this group and the unexposed controls was significant. The urinary levels of ln 1OHP and ln 8OHdG were significantly correlated, and the association was still highly significant when the effects of smoking and age were accounted for in a multiple regression analysis. Results indicate that exposure to PAH or possibly other compounds from skin contact with oils in engine rooms may cause oxidative DNA damage.

The biomaterials conundrum in tissue engineering.

PubMed

Williams, David F

2014-04-01

The development of biomaterials for use in tissue engineering processes has not so far followed a scientifically valid pathway; there have been no properly constituted specifications for these biomaterials, whose choice has often been dictated by the perceived need to comply with prior FDA approval for use of the materials in nontissue engineering applications. This short essay discusses the difficulties that have resulted in this approach and provides both conceptual and practical solutions for the future, based on sound principles of biocompatibility and the need to use tissue engineering templates that replicate the niche of the target cells.

Diesel engine emissions reduction by multiple injections having increasing pressure

DOEpatents

Reitz, Rolf D.; Thiel, Matthew P.

2003-01-01

Multiple fuel charges are injected into a diesel engine combustion chamber during a combustion cycle, and each charge after the first has successively greater injection pressure (a higher injection rate) than the prior charge. This injection scheme results in reduced emissions, particularly particulate emissions, and can be implemented by modifying existing injection system hardware. Further enhancements in emissions reduction and engine performance can be obtained by using known measures in conjunction with the invention, such as Exhaust Gas Recirculation (EGR).

Development and Performance Verification of Fiber Optic Temperature Sensors in High Temperature Engine Environments

NASA Technical Reports Server (NTRS)

Adamovsky, Grigory; Mackey, Jeffrey R.; Kren, Lawrence A.; Floyd, Bertram M.; Elam, Kristie A.; Martinez, Martel

2014-01-01

A High Temperature Fiber Optic Sensor (HTFOS) has been developed at NASA Glenn Research Center for aircraft engine applications. After fabrication and preliminary in-house performance evaluation, the HTFOS was tested in an engine environment at NASA Armstrong Flight Research Center. The engine tests enabled the performance of the HTFOS in real engine environments to be evaluated along with the ability of the sensor to respond to changes in the engine's operating condition. Data were collected prior, during, and after each test in order to observe the change in temperature from ambient to each of the various test point levels. An adequate amount of data was collected and analyzed to satisfy the research team that HTFOS operates properly while the engine was running. Temperature measurements made by HTFOS while the engine was running agreed with those anticipated.

Multi-Fuel Rotary Engine for General Aviation Aircraft

NASA Technical Reports Server (NTRS)

Jones, C.; Ellis, D. R.; Meng, P. R.

1983-01-01

Design studies, conducted for NASA, of Advanced Multi-fuel General Aviation and Commuter Aircraft Rotary Stratified Charge Engines are summarized. Conceptual design studies of an advanced engine sized to provide 186/250 shaft KW/HP under cruise conditions at 7620/25,000 m/ft. altitude were performed. Relevant engine development background covering both prior and recent engine test results of the direct injected unthrottled rotary engine technology, including the capability to interchangeably operate on gasoline, diesel fuel, kerosene, or aviation jet fuel, are presented and related to growth predictions. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 30 to 35% fuel economy improvement for the Rotary-engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

Engineering physics and mathematics division

NASA Astrophysics Data System (ADS)

Sincovec, R. F.

1995-07-01

This report provides a record of the research activities of the Engineering Physics and Mathematics Division for the period 1 Jan. 1993 - 31 Dec. 1994. This report is the final archival record of the EPM Division. On 1 Oct. 1994, ORELA was transferred to Physics Division and on 1 Jan. 1995, the Engineering Physics and Mathematics Division and the Computer Applications Division reorganized to form the Computer Science and Mathematics Division and the Computational Physics and Engineering Division. Earlier reports in this series are identified on the previous pages, along with the progress reports describing ORNL's research in the mathematical sciences prior to 1984 when those activities moved into the Engineering Physics and Mathematics Division.

Recent Changes in A-Level Mathematics: Is the Availability and Uptake of Mechanics Declining yet More?

ERIC Educational Resources Information Center

Lee, Stephen; Harrison, Martin C.; Robinson, Carol L.

2007-01-01

In the past 6 years changes have occurred in GCE A-levels. In particular, there have been several major changes in A-level Mathematics courses. As engineering students are usually required to have studied A-level Mathematics, or its equivalent, these changes have had an effect on their prior mathematical knowledge. Moreover, engineering students…

Using Self-Determination Theory to Build Communities of Support to Aid in the Retention of Women in Engineering

ERIC Educational Resources Information Center

Dell, Elizabeth M.; Verhoeven, Yen; Christman, Jeanne W.; Garrick, Robert D.

2018-01-01

Diverse perspectives are required to address the technological problems facing our world. Although women perform as well as their male counterparts in math and science prior to entering college, the numbers of women students entering and completing engineering programmes are far below their representation in the workforce. This paper reports on a…

46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

Not so Global: A Bibliometric Look at Engineering Education Research

ERIC Educational Resources Information Center

Williams, Bill; Wankat, Phillip C.; Neto, Pedro

2018-01-01

It has been suggested that Engineering Education Research (EER) is going global. If this were the case we would assume that the research of EER scholars in different parts of the globe would be informed by literature describing prior work within and beyond their home country/region. The authors set out to test this hypothesis by applying citation…

Saturn Apollo Program

NASA Image and Video Library

1969-07-01

A technician can be seen working atop the white room across from the escape tower of the Apollo 11 spacecraft a few days prior to the launch of the Saturn V moon rocket. The towering 363-foot Saturn V was a multi-stage, multi-engine launch vehicle standing taller than the Statue of Liberty. Altogether, the Saturn V engines produced as much power as 85 Hoover Dams

Refined Exploration of Turbofan Design Options for an Advanced Single-Aisle Transport

NASA Technical Reports Server (NTRS)

Guynn, Mark D.; Berton, Jeffrey J.; Fisher, Kenneth L.; Haller, William J.; Tong, Michael T.; Thurman, Douglas R.

2011-01-01

A comprehensive exploration of the turbofan engine design space for an advanced technology single-aisle transport (737/A320 class aircraft) was conducted previously by the authors and is documented in a prior report. Through the course of that study and in a subsequent evaluation of the approach and results, a number of enhancements to the engine design ground rules and assumptions were identified. A follow-on effort was initiated to investigate the impacts of these changes on the original study results. The fundamental conclusions of the prior study were found to still be valid with the revised engine designs. The most significant impact of the design changes was a reduction in the aircraft weight and block fuel penalties incurred with low fan pressure ratio, ultra-high bypass ratio designs. This enables lower noise levels to be pursued (through lower fan pressure ratio) with minor negative impacts on aircraft weight and fuel efficiency. Regardless of the engine design selected, the results of this study indicate the potential for the advanced aircraft to realize substantial improvements in fuel efficiency, emissions, and noise compared to the current vehicles in this size class.

Searching Choices: Quantifying Decision-Making Processes Using Search Engine Data.

PubMed

Moat, Helen Susannah; Olivola, Christopher Y; Chater, Nick; Preis, Tobias

2016-07-01

When making a decision, humans consider two types of information: information they have acquired through their prior experience of the world, and further information they gather to support the decision in question. Here, we present evidence that data from search engines such as Google can help us model both sources of information. We show that statistics from search engines on the frequency of content on the Internet can help us estimate the statistical structure of prior experience; and, specifically, we outline how such statistics can inform psychological theories concerning the valuation of human lives, or choices involving delayed outcomes. Turning to information gathering, we show that search query data might help measure human information gathering, and it may predict subsequent decisions. Such data enable us to compare information gathered across nations, where analyses suggest, for example, a greater focus on the future in countries with a higher per capita GDP. We conclude that search engine data constitute a valuable new resource for cognitive scientists, offering a fascinating new tool for understanding the human decision-making process. Copyright © 2016 The Authors. Topics in Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

Analytical Design Package (ADP2): A computer aided engineering tool for aircraft transparency design

NASA Technical Reports Server (NTRS)

Wuerer, J. E.; Gran, M.; Held, T. W.

1994-01-01

The Analytical Design Package (ADP2) is being developed as a part of the Air Force Frameless Transparency Program (FTP). ADP2 is an integrated design tool consisting of existing analysis codes and Computer Aided Engineering (CAE) software. The objective of the ADP2 is to develop and confirm an integrated design methodology for frameless transparencies, related aircraft interfaces, and their corresponding tooling. The application of this methodology will generate high confidence for achieving a qualified part prior to mold fabrication. ADP2 is a customized integration of analysis codes, CAE software, and material databases. The primary CAE integration tool for the ADP2 is P3/PATRAN, a commercial-off-the-shelf (COTS) software tool. The open architecture of P3/PATRAN allows customized installations with different applications modules for specific site requirements. Integration of material databases allows the engineer to select a material, and those material properties are automatically called into the relevant analysis code. The ADP2 materials database will be composed of four independent schemas: CAE Design, Processing, Testing, and Logistics Support. The design of ADP2 places major emphasis on the seamless integration of CAE and analysis modules with a single intuitive graphical interface. This tool is being designed to serve and be used by an entire project team, i.e., analysts, designers, materials experts, and managers. The final version of the software will be delivered to the Air Force in Jan. 1994. The Analytical Design Package (ADP2) will then be ready for transfer to industry. The package will be capable of a wide range of design and manufacturing applications.

Bioprinting of Cartilage and Skin Tissue Analogs Utilizing a Novel Passive Mixing Unit Technique for Bioink Precellularization

PubMed Central

Thayer, Patrick Scott; Orrhult, Linnea Stridh; Martínez, Héctor

2018-01-01

Bioprinting is a powerful technique for the rapid and reproducible fabrication of constructs for tissue engineering applications. In this study, both cartilage and skin analogs were fabricated after bioink pre-cellularization utilizing a novel passive mixing unit technique. This technique was developed with the aim to simplify the steps involved in the mixing of a cell suspension into a highly viscous bioink. The resolution of filaments deposited through bioprinting necessitates the assurance of uniformity in cell distribution prior to printing to avoid the deposition of regions without cells or retention of large cell clumps that can clog the needle. We demonstrate the ability to rapidly blend a cell suspension with a bioink prior to bioprinting of both cartilage and skin analogs. Both tissue analogs could be cultured for up to 4 weeks. Histological analysis demonstrated both cell viability and deposition of tissue specific extracellular matrix (ECM) markers such as glycosaminoglycans (GAGs) and collagen I respectively. PMID:29364216

SSME turbopump technology improvements via transient rotordynamic analysis

NASA Technical Reports Server (NTRS)

Childs, D. W.

1975-01-01

The rotordynamic behavior of the high pressure oxygen turbopump and high pressure fuel pump was analyzed for the Space Shuttle Main Engine. The identification of potential rotordynamic problem areas which might arise during operation of these units prior to their testing was accomplished. Alternative procedures for correcting potential rotordynamic problems should they occur were investigated. An adequate analytic and physical understanding of the turbopump rotordynamics was developed to improve the probability of a correct diagnosis of rotordynamic problems from test data. Transient rotordynamic models were developed for both turbopumps. The transient models model the hydrodynamic forces of the turbopump seals. A linear stability analysis was performed for the turbopump rotordynamics models, which included gyroscopic effects, seal forces, speed-dependent bearing characteristics, and internal rotor damping. Results are presented and discussed.

Hazard Analysis for the Mark III Space Suit Assembly (SSA) Used in One-g Operations

NASA Technical Reports Server (NTRS)

Mitchell, Kate; Ross, Amy; Blanco, Raul; Wood, Art

2012-01-01

This Hazard Analysis document encompasses the Mark III Space Suit Assembly (SSA) and associated ancillary equipment. It has been prepared using JSC17773, "Preparing Hazard Analyses for JSC Ground Operation", as a guide. The purpose of this document is to present the potential hazards involved in ground (23 % maximum O2, One-g) operations of the Mark III and associated ancillary support equipment system. The hazards listed in this document are specific to suit operations only; each supporting facility (Bldg. 9, etc.) is responsible for test specific Hazard Analyses. A "hazard" is defined as any condition that has the potential for harming personnel or equipment. This analysis was performed to document the safety aspects associated with manned use of the Mark III for pressurized and unpressurized ambient, ground-based, One-g human testing. The hazards identified herein represent generic hazards inherent to all standard JSC test venues for nominal ground test configurations. Non-standard test venues or test specific configurations may warrant consideration of additional hazards analysis prior to test. The cognizant suit engineer is responsible for the safety of the astronaut/test subject, space suit, and suit support personnel. The test requester, for the test supported by the suit test engineer and suited subject, is responsible for overall safety and any necessary Test Readiness Reviews (TRR).

Interactive Schematic Integration Within the Propellant System Modeling Environment

NASA Technical Reports Server (NTRS)

Coote, David; Ryan, Harry; Burton, Kenneth; McKinney, Lee; Woodman, Don

2012-01-01

Task requirements for rocket propulsion test preparations of the test stand facilities drive the need to model the test facility propellant systems prior to constructing physical modifications. The Propellant System Modeling Environment (PSME) is an initiative designed to enable increased efficiency and expanded capabilities to a broader base of NASA engineers in the use of modeling and simulation (M&S) technologies for rocket propulsion test and launch mission requirements. PSME will enable a wider scope of users to utilize M&S of propulsion test and launch facilities for predictive and post-analysis functionality by offering a clean, easy-to-use, high-performance application environment.

Analysis of Cyclic Variability of Heat Release for High-EGR GDI Engine Operation with Observations on Implications for Effective Control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaul, Brian C; Wagner, Robert M; Green Jr, Johney Boyd

2013-01-01

Operation of spark-ignition (SI) engines with high levels of charge dilution through exhaust gas recirculation (EGR) achieves significant engine efficiency gains while maintaining stoichiometric operation for compatibility with three-way catalysts. Dilution levels, however, are limited by cyclic variability-including significant numbers of misfires-that becomes more pronounced with increasing dilution. This variability has been shown to have both stochastic and deterministic components. Stochastic effects include turbulence, mixing variations, and the like, while the deterministic effect is primarily due to the nonlinear dependence of flame propagation rates and ignition characteristics on the charge composition, which is influenced by the composition of residual gasesmore » from prior cycles. The presence of determinism implies that an increased understanding the dynamics of such systems could lead to effective control approaches that allow operation near the edge of stability, effectively extending the dilution limit. This nonlinear dependence has been characterized previously for homogeneous charge, port fuel-injected (PFI) SI engines operating fuel-lean as well as with inert diluents such as bottled N2 gas. In this paper, cyclic dispersion in a modern boosted gasoline direct injection (GDI) engine using a cooled external EGR loop is examined, and the potential for improvement with effective control is evaluated through the use of symbol sequence statistics and other techniques from chaos theory. Observations related to the potential implications of these results for control approaches that could effectively enable engine operation at the edge of combustion stability are noted.« less

33 CFR 277.5 - General.

Code of Federal Regulations, 2010 CFR

2010-07-01

... has established implementing procedures based on those previously adopted and utilized by the Chief of Engineers prior to 15 October 1966. This regulation adapts these cost apportionment procedures, found in...

33 CFR 277.5 - General.

Code of Federal Regulations, 2011 CFR

2011-07-01

... has established implementing procedures based on those previously adopted and utilized by the Chief of Engineers prior to 15 October 1966. This regulation adapts these cost apportionment procedures, found in...

Experience report: Using formal methods for requirements analysis of critical spacecraft software

NASA Technical Reports Server (NTRS)

Lutz, Robyn R.; Ampo, Yoko

1994-01-01

Formal specification and analysis of requirements continues to gain support as a method for producing more reliable software. However, the introduction of formal methods to a large software project is difficult, due in part to the unfamiliarity of the specification languages and the lack of graphics. This paper reports results of an investigation into the effectiveness of formal methods as an aid to the requirements analysis of critical, system-level fault-protection software on a spacecraft currently under development. Our experience indicates that formal specification and analysis can enhance the accuracy of the requirements and add assurance prior to design development in this domain. The work described here is part of a larger, NASA-funded research project whose purpose is to use formal-methods techniques to improve the quality of software in space applications. The demonstration project described here is part of the effort to evaluate experimentally the effectiveness of supplementing traditional engineering approaches to requirements specification with the more rigorous specification and analysis available with formal methods.

STS-55 pad abort: Engine 2011 oxidizer preburner augmented spark igniter check valve leak

NASA Technical Reports Server (NTRS)

1993-01-01

The STS-55 initial launch attempt of Columbia (OV102) was terminated on KSC launch pad A March 22, 1993 at 9:51 AM E.S.T. due to violation of an ME-3 (Engine 2011) Launch Commit Criteria (LCC) limit exceedance. The event description and timeline are summarized. Propellant loading was initiated on 22 March, 1993 at 1:15 AM EST. All SSME chill parameters and launch commit criteria (LCC) were nominal. At engine start plus 1.44 seconds, a Failure Identification (FID) was posted against Engine 2011 for exceeding the 50 psia Oxidizer Preburner (OPB) purge pressure redline. The engine was shut down at 1.50 seconds followed by Engines 2034 and 2030. All shut down sequences were nominal and the mission was safely aborted. The OPB purge pressure redline violation and the abort profile/overlay for all three engines are depicted. SSME Avionics hardware and software performed nominally during the incident. A review of vehicle data table (VDT) data and controller software logic revealed no failure indications other than the single FID 013-414, OPB purge pressure redline exceeded. Software logic was executed according to requirements and there was no anomalous controller software operation. Immediately following the abort, a Rocketdyne/NASA failure investigation team was assembled. The team successfully isolated the failure cause to the oxidizer preburner augmented spark igniter purge check valve not being fully closed due to contamination. The source of the contaminant was traced to a cut segment from a rubber O-ring which was used in a fine clean tool during valve production prior to 1992. The valve was apparently contaminated during its fabrication in 1985. The valve had performed acceptably on four previous flights of the engine, and SSME flight history shows 780 combined check valve flights without failure. The failure of an Engine 3 (SSME No. 2011) check valve to close was sensed by onboard engine instruments even though all other engine operations were normal. This resulted in an engine shutdown and safe sequential shutdown of all three engines prior to ignition of the solid boosters.

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 56: Technical Communications in Engineering and Science: The Practices Within a Government Defense Laboratory

NASA Technical Reports Server (NTRS)

VonSeggern, Marilyn; Jourdain, Janet M.; Pinelli, Thomas E.

1996-01-01

Research in recent decades has identified the varied information needs of engineers versus scientists. While most of that research looked at the differences among organizations, we surveyed engineers and scientists within a single Air Force research and development laboratory about their information gathering, usage, and production practices. The results of the Phillips Laboratory survey confirm prior assumptions about distinctions between engineering and science. Because military employees responded at a much higher rate than civilian staff, the survey also became an opportunity to profile a little-known segment of the engineer/scientist population. In addition to the effect Phillips Laboratory's stated mission may have on member engineers and scientists, other factors causing variations in technical communication and information-related activities are identified.

Directed evolution and synthetic biology applications to microbial systems.

PubMed

Bassalo, Marcelo C; Liu, Rongming; Gill, Ryan T

2016-06-01

Biotechnology applications require engineering complex multi-genic traits. The lack of knowledge on the genetic basis of complex phenotypes restricts our ability to rationally engineer them. However, complex phenotypes can be engineered at the systems level, utilizing directed evolution strategies that drive whole biological systems toward desired phenotypes without requiring prior knowledge of the genetic basis of the targeted trait. Recent developments in the synthetic biology field accelerates the directed evolution cycle, facilitating engineering of increasingly complex traits in biological systems. In this review, we summarize some of the most recent advances in directed evolution and synthetic biology that allows engineering of complex traits in microbial systems. Then, we discuss applications that can be achieved through engineering at the systems level. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multi-fuel rotary engine for general aviation aircraft

NASA Technical Reports Server (NTRS)

Jones, C.; Ellis, D. R.; Meng, P. R.

1983-01-01

Design studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, an advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at 7620 (25,000 m/ft) altitude. A follow on study extended the results to larger (2500 hp max.) engine sizes suitable for applications such as commuter transports and helicopters. The study engine designs were derived from relevant engine development background including both prior and recent engine test results using direct injected unthrottled rotary engine technology. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 27 to 33 percent fuel economy improvement for the rotary engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed. Previously announced in STAR as N83-18910

The Application of V&V within Reuse-Based Software Engineering

NASA Technical Reports Server (NTRS)

Addy, Edward

1996-01-01

Verification and Validation (V&V) is performed during application development for many systems, especially safety-critical and mission-critical systems. The V&V process is intended to discover errors as early as possible during the development process. Early discovery is important in order to minimize the cost and other impacts of correcting these errors. In reuse-based software engineering, decisions on the requirements, design and even implementation of domain assets can can be made prior to beginning development of a specific system. in order to bring the effectiveness of V&V to bear within reuse-based software engineering. V&V must be incorporated within the domain engineering process.

Recommended Practices for Measurement of Gas Path Pressures and Temperatures for Performance Assessment of Aircraft Turbine Engines and Components (Les Methodes Recommandees pour la Mesure de la Pression et de la Temperature de la Veine Gazeuse en Vue de l’Evaluation des Performances des Turbines Aeronautiques et de leurs Composants

DTIC Science & Technology

1990-06-01

reduction software , prior to converting all remaining test which requires internal compensation. T he r sidual effect is pressures to engineering units...Reduction Conversion of Millivolts to Engineering Units. Carrying out numerical integrations to obtain area and mass weighted averages for various...Performance Assessment of Aircraft Turbine Engines and Components (Les MWthodes Recommande’es pour la Mesure de la Pression et de ]a Temperature de la

Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

NASA Technical Reports Server (NTRS)

Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

2012-01-01

Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

Faults Discovery By Using Mined Data

NASA Technical Reports Server (NTRS)

Lee, Charles

2005-01-01

Fault discovery in the complex systems consist of model based reasoning, fault tree analysis, rule based inference methods, and other approaches. Model based reasoning builds models for the systems either by mathematic formulations or by experiment model. Fault Tree Analysis shows the possible causes of a system malfunction by enumerating the suspect components and their respective failure modes that may have induced the problem. The rule based inference build the model based on the expert knowledge. Those models and methods have one thing in common; they have presumed some prior-conditions. Complex systems often use fault trees to analyze the faults. Fault diagnosis, when error occurs, is performed by engineers and analysts performing extensive examination of all data gathered during the mission. International Space Station (ISS) control center operates on the data feedback from the system and decisions are made based on threshold values by using fault trees. Since those decision-making tasks are safety critical and must be done promptly, the engineers who manually analyze the data are facing time challenge. To automate this process, this paper present an approach that uses decision trees to discover fault from data in real-time and capture the contents of fault trees as the initial state of the trees.

Hierarchical Task Network Prototyping In Unity3d

DTIC Science & Technology

2016-06-01

visually debug. Here we present a solution for prototyping HTNs by extending an existing commercial implementation of Behavior Trees within the Unity3D game ...HTN, dynamic behaviors, behavior prototyping, agent-based simulation, entity-level combat model, game engine, discrete event simulation, virtual...commercial implementation of Behavior Trees within the Unity3D game engine prior to building the HTN in COMBATXXI. Existing HTNs were emulated within

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

Expedition 23 NASA Flight Engineer Tracy Caldwell Dyson, left, Expedition 23 Soyuz Commander Alexander Skvortsov and Expedition 23 Flight Engineer Mikhail Kornienko, third from left, walk out to salute Head of the Russian Federal Space Agency Anatoly Perminov, third from right, prior to their launch onboard the Soyuz TMA-18 to the International Space Station (ISS), Friday, April 2, 2010 in Baikonur, Kazakhstan. Photo Credit: (NASA/Victor Zelentsov)

Expedition 23 Launch Day

NASA Image and Video Library

2010-04-01

Russian cosmonaut Expedition 23 Flight Engineer Mikhail Kornienko smiles as he awaits to have his Sokol suit pressure checked prior to launch, Friday, April 2, 2010, in Baikonur, Kazakhstan. Kornienko and fellow Expedition 23 crew members Soyuz Commander Alexander Skvortsov and NASA Flight Engineer Tracy Caldwell Dyson launched in their Soyuz TMA-18 rocket from the Baikonur Cosmodrome in Kazakhstan on Friday, April 2, 2010. Photo Credit: (NASA/Bill Ingalls)

Expedition 18 Door Signing

NASA Image and Video Library

2008-10-11

Expedition 18 Flight Engineer Yuri V. Lonchakov signs the door of a hotel room at the Cosmonaut Hotel prior to departing for the launch aboard a Soyuz TMA-13 spacecraft, Sunday, Oct. 12, 2008, in Baikonur, Kazakhstan. The Soyuz TMA-13 spacecraft launched from the Baikonur Cosmodrome in Kazakhstan carrying Expedition 18 Commander Michael Fincke, Flight Engineer Yuri V. Lonchakov and American spaceflight participant Richard Garriott. Photo Credit: (NASA/Bill Ingalls)

13th Annual Systems Engineering Conference. Volume 3

DTIC Science & Technology

2010-10-28

Case for Considering Acquisition Program Executability Prior to Materiel Development Decision (MDD), Mr. Gregory Laushine, SAIC · 10810...David Asiello, Office Deputy Under Secretary of Defense (I&E) · 10907 - A Case Study of an Evolving ESOH Program — One Company’s Perspective, Mr...10732 - R&D Transition Interface with Early Systems Engineering: SEALION and Open Systems Case Studies, Mr. Michael Bosworth, Naval Sea Systems

Tim Johansson | NREL

Science.gov Websites

performed maintenance, operation, and repair on laboratory support systems, including some minor /electrical technician Chief Engineer, Tim leads the maintenance crew at NWTC. Prior to joining NREL, Tim was

Cloud Computing: Virtual Clusters, Data Security, and Disaster Recovery

NASA Astrophysics Data System (ADS)

Hwang, Kai

Dr. Kai Hwang is a Professor of Electrical Engineering and Computer Science and Director of Internet and Cloud Computing Lab at the Univ. of Southern California (USC). He received the Ph.D. in Electrical Engineering and Computer Science from the Univ. of California, Berkeley. Prior to joining USC, he has taught at Purdue Univ. for many years. He has also served as a visiting Chair Professor at Minnesota, Hong Kong Univ., Zhejiang Univ., and Tsinghua Univ. He has published 8 books and over 210 scientific papers in computer science/engineering.

Demonstration and evaluation of gas turbine transit buses

NASA Technical Reports Server (NTRS)

1983-01-01

The Gas Turbine Transit Bus Demonstration Program was designed to demonstrate and evaluate the operation of gas turbine engines in transit coaches in revenue service compared with diesel powered coaches. The main objective of the program was to accelerate development and commercialization of automotive gas turbines. The benefits from the installation of this engine in a transit coach were expected to be reduced weight, cleaner exhaust emissions, lower noise levels, reduced engine vibration and maintenance requirements, improved reliability and vehicle performance, greater engine braking capability, and superior cold weather starting. Four RTS-II advanced design transit coaches were converted to gas turbine power using engines and transmissions. Development, acceptance, performance and systems tests were performed on the coaches prior to the revenue service demonstration.

Fuel Flexibility: Landfill Gas Contaminant Mitigation for Power Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Storey, John Morse; Theiss, Timothy J; Kass, Michael D

This research project focused on the mitigation of silica damage to engine-based renewable landfill gas energy systems. Characterization of the landfill gas siloxane contamination, combined with characterization of the silica deposits in engines, led to development of two new mitigation strategies. The first involved a novel method for removing the siloxanes and other heavy contaminants from the landfill gas prior to use by the engines. The second strategy sought to interrupt the formation of hard silica deposits in the engine itself, based on inspection of failed landfill gas engine parts. In addition to mitigation, the project had a third taskmore » to develop a robust sensor for siloxanes that could be used to control existing and/or future removal processes.« less

On predicting monitoring system effectiveness

NASA Astrophysics Data System (ADS)

Cappello, Carlo; Sigurdardottir, Dorotea; Glisic, Branko; Zonta, Daniele; Pozzi, Matteo

2015-03-01

While the objective of structural design is to achieve stability with an appropriate level of reliability, the design of systems for structural health monitoring is performed to identify a configuration that enables acquisition of data with an appropriate level of accuracy in order to understand the performance of a structure or its condition state. However, a rational standardized approach for monitoring system design is not fully available. Hence, when engineers design a monitoring system, their approach is often heuristic with performance evaluation based on experience, rather than on quantitative analysis. In this contribution, we propose a probabilistic model for the estimation of monitoring system effectiveness based on information available in prior condition, i.e. before acquiring empirical data. The presented model is developed considering the analogy between structural design and monitoring system design. We assume that the effectiveness can be evaluated based on the prediction of the posterior variance or covariance matrix of the state parameters, which we assume to be defined in a continuous space. Since the empirical measurements are not available in prior condition, the estimation of the posterior variance or covariance matrix is performed considering the measurements as a stochastic variable. Moreover, the model takes into account the effects of nuisance parameters, which are stochastic parameters that affect the observations but cannot be estimated using monitoring data. Finally, we present an application of the proposed model to a real structure. The results show how the model enables engineers to predict whether a sensor configuration satisfies the required performance.

Knowledge-Based Parallel Performance Technology for Scientific Application Competitiveness Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malony, Allen D; Shende, Sameer

The primary goal of the University of Oregon's DOE "œcompetitiveness" project was to create performance technology that embodies and supports knowledge of performance data, analysis, and diagnosis in parallel performance problem solving. The target of our development activities was the TAU Performance System and the technology accomplishments reported in this and prior reports have all been incorporated in the TAU open software distribution. In addition, the project has been committed to maintaining strong interactions with the DOE SciDAC Performance Engineering Research Institute (PERI) and Center for Technology for Advanced Scientific Component Software (TASCS). This collaboration has proved valuable for translationmore » of our knowledge-based performance techniques to parallel application development and performance engineering practice. Our outreach has also extended to the DOE Advanced CompuTational Software (ACTS) collection and project. Throughout the project we have participated in the PERI and TASCS meetings, as well as the ACTS annual workshops.« less

Computational Study of Primary Electrons in the Cusp Region of an Ion Engine's Discharge Chamber

NASA Technical Reports Server (NTRS)

Stueber, Thomas J. (Technical Monitor); Deshpande, Shirin S.; Mahalingam, Sudhakar; Menart, James A.

2004-01-01

In this work a computer code called PRIMA is used to study the motion of primary electrons in the magnetic cusp region of the discharge chamber of an ion engine. Even though the amount of wall area covered by the cusps is very small, the cusp regions are important because prior computational analyses have indicated that most primary electrons leave the discharge chamber through the cusps. The analysis presented here focuses on the cusp region only. The affects of the shape and size of the cusp region on primary electron travel are studied as well as the angle and location at which the electron enters the cusp region. These affects are quantified using the confinement length and the number density distributions of the primary electrons. In addition to these results comparisons of the results from PRIMA are made to experimental results for a cylindrical discharge chamber with two magnetic rings. These comparisons indicate the validity of the computer code called PRIMA.

DNA Nanostructure-based Interfacial engineering for PCR-free ultrasensitive electrochemical analysis of microRNA

NASA Astrophysics Data System (ADS)

Wen, Yanli; Pei, Hao; Shen, Ye; Xi, Junjie; Lin, Meihua; Lu, Na; Shen, Xizhong; Li, Jiong; Fan, Chunhai

2012-11-01

MicroRNAs (miRNAs) have been identified as promising cancer biomarkers due to their stable presence in serum. As an alternative to PCR-based homogenous assays, surface-based electrochemical biosensors offer great opportunities for low-cost, point-of-care tests (POCTs) of disease-associated miRNAs. Nevertheless, the sensitivity of miRNA sensors is often limited by mass transport and crowding effects at the water-electrode interface. To address such challenges, we herein report a DNA nanostructure-based interfacial engineering approach to enhance binding recognition at the gold electrode surface and drastically improve the detection sensitivity. By employing this novel strategy, we can directly detect as few as attomolar (<1, 000 copies) miRNAs with high single-base discrimination ability. Given that this ultrasensitive electrochemical miRNA sensor (EMRS) is highly reproducible and essentially free of prior target labeling and PCR amplification, we also demonstrate its application by analyzing miRNA expression levels in clinical samples from esophageal squamous cell carcinoma (ESCC) patients.

Clinical significance of computed tomography assessment for third molar surgery

PubMed Central

Nakamori, Kenji; Tomihara, Kei; Noguchi, Makoto

2014-01-01

Surgical extraction of the third molar is the most commonly performed surgical procedure in the clinical practice of oral surgery. Third molar surgery is warranted when there is inadequate space for eruption, malpositioning, or risk for cyst or odontogenic tumor formation. Preoperative assessment should include a detailed morphologic analysis of the third molar and its relationship to adjacent structures and surrounding tissues. Due to developments in medical engineering technology, computed tomography (CT) now plays a critical role in providing the clear images required for adequate assessment prior to third molar surgery. Removal of the maxillary third molar is associated with a risk for maxillary sinus perforation, whereas removal of the mandibular third molar can put patients at risk for a neurosensory deficit from damage to the lingual nerve or inferior alveolar nerve. Multiple factors, including demographic, anatomic, and treatment-related factors, influence the incidence of nerve injury during or following removal of the third molar. CT assessment of the third molar prior to surgery can identify some of these risk factors, such as the absence of cortication between the mandibular third molar and the inferior alveolar canal, prior to surgery to reduce the risk for nerve damage. This topic highlight presents an overview of the clinical significance of CT assessment in third molar surgery. PMID:25071882

Aviation Safety Modeling and Simulation (ASMM) Propulsion Fleet Modeling: A Tool for Semi-Automatic Construction of CORBA-based Applications from Legacy Fortran Programs

NASA Technical Reports Server (NTRS)

Sang, Janche

2003-01-01

Within NASA's Aviation Safety Program, NASA GRC participates in the Modeling and Simulation Project called ASMM. NASA GRC s focus is to characterize the propulsion systems performance from a fleet management and maintenance perspective by modeling and through simulation predict the characteristics of two classes of commercial engines (CFM56 and GE90). In prior years, the High Performance Computing and Communication (HPCC) program funded, NASA Glenn in developing a large scale, detailed simulations for the analysis and design of aircraft engines called the Numerical Propulsion System Simulation (NPSS). Three major aspects of this modeling included the integration of different engine components, coupling of multiple disciplines, and engine component zooming at appropriate level fidelity, require relatively tight coupling of different analysis codes. Most of these codes in aerodynamics and solid mechanics are written in Fortran. Refitting these legacy Fortran codes with distributed objects can increase these codes reusability. Aviation Safety s modeling and simulation use in characterizing fleet management has similar needs. The modeling and simulation of these propulsion systems use existing Fortran and C codes that are instrumental in determining the performance of the fleet. The research centers on building a CORBA-based development environment for programmers to easily wrap and couple legacy Fortran codes. This environment consists of a C++ wrapper library to hide the details of CORBA and an efficient remote variable scheme to facilitate data exchange between the client and the server model. Additionally, a Web Service model should also be constructed for evaluation of this technology s use over the next two- three years.

Environmental (Saprozoic) Pathogens of Engineered Water Systems: Understanding Their Ecology for Risk Assessment and Management

PubMed Central

Ashbolt, Nicholas J.

2015-01-01

Major waterborne (enteric) pathogens are relatively well understood and treatment controls are effective when well managed. However, water-based, saprozoic pathogens that grow within engineered water systems (primarily within biofilms/sediments) cannot be controlled by water treatment alone prior to entry into water distribution and other engineered water systems. Growth within biofilms or as in the case of Legionella pneumophila, primarily within free-living protozoa feeding on biofilms, results from competitive advantage. Meaning, to understand how to manage water-based pathogen diseases (a sub-set of saprozoses) we need to understand the microbial ecology of biofilms; with key factors including biofilm bacterial diversity that influence amoebae hosts and members antagonistic to water-based pathogens, along with impacts from biofilm substratum, water temperature, flow conditions and disinfectant residual—all control variables. Major saprozoic pathogens covering viruses, bacteria, fungi and free-living protozoa are listed, yet today most of the recognized health burden from drinking waters is driven by legionellae, non-tuberculous mycobacteria (NTM) and, to a lesser extent, Pseudomonas aeruginosa. In developing best management practices for engineered water systems based on hazard analysis critical control point (HACCP) or water safety plan (WSP) approaches, multi-factor control strategies, based on quantitative microbial risk assessments need to be developed, to reduce disease from largely opportunistic, water-based pathogens. PMID:26102291

Daniel Laird | NREL

Science.gov Websites

the high-fidelity modeling, wind plant controls, and rotor dynamics focus areas. Prior to joining NREL , composite materials, and blade reliability. Education M.S. and Ph.D. in Mechanical Engineering, University

Novel strategy for protein exploration: high-throughput screening assisted with fuzzy neural network.

PubMed

Kato, Ryuji; Nakano, Hideo; Konishi, Hiroyuki; Kato, Katsuya; Koga, Yuchi; Yamane, Tsuneo; Kobayashi, Takeshi; Honda, Hiroyuki

2005-08-19

To engineer proteins with desirable characteristics from a naturally occurring protein, high-throughput screening (HTS) combined with directed evolutional approach is the essential technology. However, most HTS techniques are simple positive screenings. The information obtained from the positive candidates is used only as results but rarely as clues for understanding the structural rules, which may explain the protein activity. In here, we have attempted to establish a novel strategy for exploring functional proteins associated with computational analysis. As a model case, we explored lipases with inverted enantioselectivity for a substrate p-nitrophenyl 3-phenylbutyrate from the wild-type lipase of Burkhorderia cepacia KWI-56, which is originally selective for (S)-configuration of the substrate. Data from our previous work on (R)-enantioselective lipase screening were applied to fuzzy neural network (FNN), bioinformatic algorithm, to extract guidelines for screening and engineering processes to be followed. FNN has an advantageous feature of extracting hidden rules that lie between sequences of variants and their enzyme activity to gain high prediction accuracy. Without any prior knowledge, FNN predicted a rule indicating that "size at position L167," among four positions (L17, F119, L167, and L266) in the substrate binding core region, is the most influential factor for obtaining lipase with inverted (R)-enantioselectivity. Based on the guidelines obtained, newly engineered novel variants, which were not found in the actual screening, were experimentally proven to gain high (R)-enantioselectivity by engineering the size at position L167. We also designed and assayed two novel variants, namely FIGV (L17F, F119I, L167G, and L266V) and FFGI (L17F, L167G, and L266I), which were compatible with the guideline obtained from FNN analysis, and confirmed that these designed lipases could acquire high inverted enantioselectivity. The results have shown that with the aid of bioinformatic analysis, high-throughput screening can expand its potential for exploring vast combinatorial sequence spaces of proteins.

Student attraction to engineering through flexibility and breadth in the curriculum

NASA Astrophysics Data System (ADS)

Alpay, E.

2013-03-01

Several European universities provide entry to general engineering studies prior to degree specialisation. The potential advantages of such entry include the provision of a broader foundation in engineering fundamentals, the option for students to defer specialisation until a greater awareness of the different engineering disciplines and the preparation of students for a more versatile career. In this paper, the attractiveness of general engineering (specifically in the first year of study) is explored through a national (UK) survey on pre-university students. Attention is given to gauging student enthusiasm for flexibility in engineering specialisation, combined degree options and exposure to other non-technical courses. The findings indicate that a general engineering programme is highly attractive to students who are currently considering an engineering degree. The programme is also attractive to some students who had previously not considered engineering. For both sets of students, the desire for education on broader topics is indicated, specifically in areas of leadership, teamwork and business skills, and more generally self-awareness and personal development.

Separation of organic ion exchange resins from sludge -- engineering study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, J.B.

1998-08-25

This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

Weapon System Requirements: Detailed Systems Engineering Prior to Product Development Positions Programs for Success

DTIC Science & Technology

2016-11-01

systems engineering had better outcomes. For example, the Small Diameter Bomb Increment I program, which delivered within cost and schedule estimates ...its current portfolio. This portfolio has experienced cost growth of 48 percent since first full estimates and average delays in delivering initial...stable design, building and testing of prototypes, and demonstration of mature production processes. • Realistic cost estimate : Sound cost estimates

Advanced Turbine Engine Seal Test

DTIC Science & Technology

1976-07-01

Transpiration- Cooled Shroud Segments. 67. ATEST Shroud Rub Pin Heights and Mid-Chord Runout . 68. Locations of Nine-Point Runout Check on Shroud Surface...69. ATEST Shroud Leading Edge Runout . 70. ATEST Shroud Trailing Edge Runout . 71. ATEST Shroud Support Posttest Runout . 72. ATEST Shroud Flow Zones...at General Electric on many prior engines with good success. It Involves the use of a grinding wheel in conjunction with a cutting fluid which is

JPRS Report, Science & Technology, USSR: Science & Technology Policy

DTIC Science & Technology

1988-11-14

the Chemistry Department of Latvian State University. But even prior to graduating from Latvian State University, he joined the Riga Citric Acid ...introduction into production of a technology of micro- biological production of citric acid from molasses. On graduating from Latvian State University...R.Ya. Karklin received a proposal in 1952 to become the chief engineer of the Riga Citric Acid Plant. One of the young chief engineer’s first

Environmental chemistry: Volume A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yen, T.F.

1999-08-01

This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

Influence of solder joint length to the mechanical aspect during the thermal stress analysis

NASA Astrophysics Data System (ADS)

Tan, J. S.; Khor, C. Y.; Rahim, Wan Mohd Faizal Wan Abd; Ishak, Muhammad Ikman; Rosli, M. U.; Jamalludin, Mohd Riduan; Zakaria, M. S.; Nawi, M. A. M.; Aziz, M. S. Abdul; Ani, F. Che

2017-09-01

Solder joint is an important interconnector in surface mount technology (SMT) assembly process. The real time stress, strain and displacement of the solder joint is difficult to observe and assess the experiment. To tackle these problems, simulation analysis was employed to study the von Mises stress, strain and displacement in the thermal stress analysis by using Finite element based software. In this study, a model of leadless electronic package was considered. The thermal stress analysis was performed to investigate the effect of the solder length to those mechanical aspects. The simulation results revealed that solder length gives significant effect to the maximum von Mises stress to the solder joint. Besides, changes in solder length also influence the displacement of the solder joint in the thermal environment. The increment of the solder length significantly reduces the von Mises stress and strain on the solder joint. Thus, the understanding of the physical parameter for solder joint is important for engineer prior to designing the solder joint of the electronic component.