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General Discussion

15303 threads, 286352 comments (33 Viewing)

Solar Eclipse

08/16/2017 by NSS
Just curious, How large would something need to be when in a geosynchronous orbit, to also have the aprox 1/2 a degree diameter so periodically, artif...
Views: 43, Comments: 8
Last comment 08/16/2017 by Usbport

The Beginning of the End of Tesla

08/15/2017 by wrenchtwirler
Views: 282, Comments: 23
Last comment 08/16/2017 by SolarEagle

Buildup of Mold

08/15/2017 by agua_doc
I suffer from sleep apnea and use a CPAP machine. I have noticed the buildup of a "pink" substance that looks like a mold on the damp plastic surfaces...
Views: 173, Comments: 11
Last comment 08/16/2017 by SolarEagle

What is the True Gravitational Measurement of Weight?

08/15/2017 by SolarEagle
I was thinking the other day, so we measure our weight on the surface of the Earth, but what about the force of the Earth's rotation, wouldn't that ha...
Views: 457, Comments: 63
Last comment 08/16/2017 by SolarEagle
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Commercial Space

1990 threads, 3798 comments (0 Viewing)

How to Improve ESP Performance or Downhole Measuring Systems of the Future

08/14/2017 by Dalia
The questions of time and costs saving, efficiency increase, safety and innovative technologies are the most actual and important in the sphere of o...
Views: 27, Comments: 4
Last comment 08/14/2017 by Dalia

Finding Buyers (Importers) Mechanical Parts

08/14/2017 by nhamlv
Hello, everyone. I am a member of Vietnam automation and Technical Industries JSC. We are professional company in processing precision mechanics, jig...
Views: 11, Comments: 0

Bid Performance Amount

08/02/2017 by Anonymous Poster
Hi, Bid performance amount is given as 20% of contract amount for a particular project. I think normally it is 10%. Does this men that the client/em...
Views: 49, Comments: 0
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CR4 Feedback

692 threads, 12068 comments (0 Viewing)

Android App

07/29/2017 by JohnDG
^Please tell me where I can download the Android mobile Globalspec app - I had it on my phone for ages, but it somehow got deleted. Thanks in advance.
Views: 195, Comments: 2
Last comment 07/30/2017 by JohnDG

Who Is Online - Link Not Opening

07/27/2017 by dhayanandhan
To: cr4 admin. Whenever I open cr4, I open the link who is on line In the past 15 days, only on 3 occassions the above link has opened. whenever I o...
Views: 67, Comments: 4
Last comment 07/27/2017 by BestInShow
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See all Blog Entries

Section Blogs

The Engineer's Notebook

429 blog entries, 7123 comments (0 Viewing)

Even More Good News for Booze Lovers the World Over

08/12/2017 by M-ReeD
Recently, I wrote about how alcohol (Let’s face it! I will probably write about this topic a lot. It’s kind of in my wheelhouse.) can pres...
Views: 405, Comments: 16
Last comment 08/16/2017 by warped

You Aren't Paranoid! You ARE Being Watched!

08/05/2017 by M-ReeD
Ever get the sensation that someone is staring at you as you mindlessly watch television or cook dinner? Is the feeling sometimes so intense that you...
Views: 614, Comments: 15
Last comment 08/15/2017 by 70AARCuda
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WoW Blog (Woman of the Week)

196 blog entries, 568 comments (0 Viewing)

Woman of the Week – Mary Eliza Mahoney

08/07/2017 by lmno24
Mary Eliza Mahoney was the first African American to study and work as a professionally trained nurse in the United States, graduating in 1879. Mahone...
Views: 135, Comments: 0

Woman of the Week – Martha Coston

07/31/2017 by lmno24
At 21, Martha Coston found herself widowed with four young children. After her husband Benjamin Coston died, she found his plans for a pyrotechnic (si...
Views: 303, Comments: 1
Last comment 07/31/2017 by SolarEagle
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Abe's Blog

6 blog entries, 194 comments (0 Viewing)

Race Tracks Are Not Good For The Horses

08/01/2017 by amichelen
Now, in the middle of the boreal summer, the sad story of the horses at race tracks like in Saratoga Springs, comes to mind. On average 24 horses die...
Views: 762, Comments: 125
Last comment 08/14/2017 by amichelen

Hypatia of Alexandria – Part 3

11/15/2016 by amichelen
(Note: This is last part of Hypatia of Alexandri) Personal life If we have little knowledge of her scientific achievements, we know even less about...
Views: 347, Comments: 35
Last comment 11/19/2016 by TimONeill
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Challenge Questions

355 blog entries, 28542 comments (3 Viewing)

Mystery of the Part-time Stud Finder: Newsletter Challenge (August 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: Steve recently moved into a new apartment and wants to use his father’s stu...
Views: 2217, Comments: 26
Last comment 08/15/2017 by OlorinTharkun

Tricky Tubes: Newsletter Challenge (July 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: You are watching TV on an old television set with a cathode ray tube. It’s...
Views: 1534, Comments: 36
Last comment 07/21/2017 by James Stewart
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Notes & Lines

44 blog entries, 407 comments (0 Viewing)

Black Hole Music and Really Low Notes

07/13/2017 by Hannes
A colleague of mine recently heard from a friend that certain black holes make musical pitches—specifically, scientists have observed a black ho...
Views: 350, Comments: 30
Last comment 07/19/2017 by Rixter

What Did The Past Sound Like?

06/15/2017 by Hannes
Growing up in the early ‘90s, my family still had a big cream-colored rotary phone stuck to our kitchen wall. At the time I didn’t realize...
Views: 468, Comments: 40
Last comment 07/13/2017 by phoenix911
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Defense & Security Technology

117 blog entries, 1655 comments (0 Viewing)

Multi-touch System Allows Navy Flight Decks to Shuffle Configurations

06/26/2017 by Engineering360 eNewsletter
The systems, designated the Deployable Ship Integration Multitouch Systems, upgrade the "Quija board" currently used to organize hanger bays by allowi...
Views: 133, Comments: 0

Autonomous, Reusable Experimental Spacecraft Being Developed by Boeing and DARPA

06/05/2017 by Engineering360 eNewsletter
Boeing is collaborating with the U.S. Defense Advanced Research Projects Agency (DARPA) to design and test an experimental spaceplane capable of reach...
Views: 166, Comments: 0
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45 blog entries, 409 comments (0 Viewing)

Physicists Create a Fluid With Negative Mass

04/20/2017 by Bayes
One of the interesting things you learn early on in physics is that there is nothing in physics that forbids negative mass values. There has long been...
Views: 818, Comments: 53
Last comment 07/24/2017 by James Stewart

NASA Announcement Today on Potential Habitats for Alien Life

04/13/2017 by Bayes
NASA Announcement Today at 2 p.m. EDT NASA will discuss new results about ocean worlds in our solar system from the agency’s Cassini spacecraft...
Views: 161, Comments: 1
Last comment 04/17/2017 by James Stewart
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"On This Day" In Engineering History

242 blog entries, 842 comments (0 Viewing)

April 19, 1906—The Death of Nobel Prize Laureate Pierre Curie

04/19/2017 by MaggieMc
Thinking back to science class, Curie is a familiar name. Marie Curie is a favorite subject in many courses, especially due to organizing mobile X-ray...
Views: 359, Comments: 2
Last comment 04/20/2017 by MaggieMc

February 17, 1864—The Hunley Sinks the Housatonic

02/17/2017 by Hannes
On this day in 1864, the pioneering Confederate submarine H.L. Hunley rammed and sank the USS Housatonic during the US Civil War. She was the first co...
Views: 447, Comments: 2
Last comment 02/18/2017 by ronc
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Editor's Desk

95 blog entries, 362 comments (0 Viewing)

Engineering Job Growth Shows Positive Outlook

04/08/2017 by Engineering360 eNewsletter
The most recent projections from the U.S. Bureau of Labor Statistics concur that jobs in engineering, and other STEM fields, would likely provide the...
Views: 216, Comments: 0

3D-printed Artwork Created on the International Space Station

02/28/2017 by Engineering360 eNewsletter
The first-ever off-world artwork by Eyal Gever demonstrates what humanity can achieve through positivity, and lightens the mood with laughter in space...
Views: 124, Comments: 0
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Animal Science

238 blog entries, 2171 comments (0 Viewing)

Dogs on the Brain

03/13/2017 by MaggieMc
My good friend just adopted a puppy, and with all the pictures coming my way, I have dogs on the brain. Evidently, so do researchers. Two studies were...
Views: 504, Comments: 11
Last comment 03/16/2017 by James Stewart

Kid’s Best Friend

02/01/2017 by MaggieMc
Last week, “A Dog’s Purpose” was released in theaters. The movie—which “shares the soulful and surprising story of one d...
Views: 282, Comments: 15
Last comment 02/05/2017 by JPool
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The CR4 Admin Blog

101 blog entries, 1492 comments (0 Viewing)

2016 Year in Review & Farewell

03/07/2017 by SavvyExacta
It’s a little late for a 2016 year in review but I thought it was a fitting subject for my final CR4 post. You see, I’m moving on to a new...
Views: 485, Comments: 16
Last comment 03/09/2017 by jdretired

Across Five Years (A CR4 Clip Show)

12/28/2016 by HUSH
It certainly doesn’t happen as much today, in the age of streaming services and binge watching. But up until recently the ‘clip show’...
Views: 258, Comments: 3
Last comment 12/30/2016 by Andrew Westman
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What Is It?

69 blog entries, 1869 comments (0 Viewing)

What is It? for February 2

Do you know what this is? Share your guess! Submitted by CR4 user phph001.
Views: 551, Comments: 9
Last comment 02/07/2017 by ronc
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Rockaholic Adventures

50 blog entries, 611 comments (0 Viewing)

Morphology of Olympus Mons

12/05/2016 by Shawn
After discussing the morphology of Olympus Mons I felt compelled to share my intuition of the shield volcanos existence and morphology strictly throug...
Views: 306, Comments: 5
Last comment 12/08/2016 by Shawn
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Great Engineers & Scientists

145 blog entries, 501 comments (0 Viewing)

The First Lady of Structural Engineering

11/28/2016 by MaggieMc
Elmina Wilson is widely regarded as “the first lady of structural engineering.” Born on September 29, 1870, Elmina came from a family of w...
Views: 468, Comments: 2
Last comment 07/11/2017 by esperanzajpalmer
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65 blog entries, 579 comments (0 Viewing)

The San Fran Skyscraper with a Six-Inch Slant

09/28/2016 by HUSH
Skyscrapers are a lot more to a city than just real estate. They represent financial prosperity and engineering acumen. They transform the identity of...
Views: 940, Comments: 20
Last comment 01/25/2017 by MR. Guest
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TechnoTourist’s Engineering Expeditions

83 blog entries, 491 comments (0 Viewing)

A Piece of Ireland in Texas

08/23/2016 by joeymac
Everyone knows that kissing the Blarney Stone over in Ireland is supposed to give a person the gift of gab and eloquence of speech. I was fortunate en...
Views: 572, Comments: 8
Last comment 07/27/2017 by The Wizard
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Other Blog Entries of Interest

Caption This for 3/31/2017

03/31/2017 posted in Caption This!
by lmno24
This week's image: Thanks to Nigh for the submission! Keep in mind we are always looking for submissions, send us photos anytime. Be sure to vote...
Views: 574, Comments: 38
Last comment 04/07/2017 by Randall

Caption This for 3/24/2017

03/24/2017 posted in Caption This!
by MaggieMc
This weeks image: Be sure to vote for your favorite caption! Thanks to Nigh for the submission, we're always looking for more!
Views: 724, Comments: 85
Last comment 04/06/2017 by szwasta

Caption This for 3/17/2017

03/17/2017 posted in Caption This!
by lmno24
This weeks image: Be sure to vote for your favorite caption! Thanks to user sptilton for the submission.
Views: 437, Comments: 20
Last comment 03/20/2017 by Mikerho

Caption This for 3/10/2017

03/10/2017 posted in Caption This!
by MaggieMc
This week's image: Be sure to vote for your favorite caption! Thanks to Solar Eagle for the submission.
Views: 567, Comments: 49
Last comment 03/14/2017 by Mikerho

Caption This for 3/3/2017

03/03/2017 posted in Caption This!
by lmno24
This week's image: Be sure to vote for your favorite caption! Thanks to user Nigh for the submission.
Views: 664, Comments: 52
Last comment 03/10/2017 by MaggieMc