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Section Forums

General Discussion

15598 threads, 294568 comments (11 Viewing)

Cannot Recline Koken Mohawk

02/23/2018 by Pman
i bought a Koken Mohawk 1950’s model, it pumps up and down nicely, locks into place good, but I can’t get it to recline. I’ve tried...
Views: 87, Comments: 4
Last comment 02/24/2018 by Anonymous Poster

10 Biggest Breakthrough Technologies of 2018... So Far

02/23/2018 by SolarEagle
1. 3D metal printing 2. Artificial embryos 3. Sensing city 4. AI for everybody 5. Dueling neural networks 6. Babel-fish earbuds 7. Zero-carbon n...
Views: 197, Comments: 18
Last comment 02/25/2018 by tonyhemet

Reality, or Flawed Knowledge of Reality?

02/22/2018 by HiTekRedNek
Check out this link for some thought provoking ideas on perception and reality.
Views: 285, Comments: 31
Last comment 02/24/2018 by JE in Chicago
Views: 370, Comments: 41
Last comment 02/24/2018 by dkwarner
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Commercial Space

2018 threads, 3847 comments (0 Viewing)

High-Rise building Rendering Ideas

02/08/2018 by yantramstudio
Commercial high rise building rendering with live environment of surrounding building in mood of Day and Night, Concept and Design Ideas by Yantram...
Views: 20, Comments: 0


02/02/2018 by Anonymous Poster
Views: 36, Comments: 0
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CR4 Feedback

700 threads, 12238 comments (0 Viewing)

We Are Secure!

02/10/2018 by xzi
Just figured I’d point out if you haven’t noticed yet with a keen eye, CR4 (as well as a few of our other sites) are now officially “...
Views: 201, Comments: 16
Last comment 02/15/2018 by Tornado

New CR4 Members - A Silent Majority?

01/29/2018 by Doorman
By my count we have 392 new CR4 members in the last 30 days. I’m not a constant watcher of this statistic, but I tend to notice outliers and thi...
Views: 790, Comments: 94
Last comment 01/31/2018 by JE in Chicago
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Section Blogs

WoW Blog (Woman of the Week)

211 blog entries, 592 comments (0 Viewing)

Woman of the Week – Beverley Bass

02/19/2018 by lmno24
Beverley Bass was the first female captain hired by American Airlines and is perhaps best known for her quick decision making on September 11^th, 2001...
Views: 342, Comments: 6
Last comment 02/23/2018 by Doorman

Woman of the Week – Samantha Larson

02/12/2018 by lmno24
Samantha Larson is an American mountain climber from Long Beach, California. In 2007, at only 18, she became the youngest non-Nepalese woman to climb...
Views: 211, Comments: 3
Last comment 02/16/2018 by Lookfar
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The Engineer's Notebook

462 blog entries, 7571 comments (2 Viewing)

Walking Into Glass Walls

02/24/2018 by M-ReeD
In news designed to make me feel better about the number of items (cabinets, doors, people) I walk into on a daily basis, I am heartened by a recent r...
Views: 50, Comments: 2
Last comment 02/24/2018 by Usbport

All That Glitters

02/17/2018 by M-ReeD
Yes. I am absolutely concerned about glitter’s impact on ocean life. Yet, self-involved as I am, I am slightly more concerned about the impact...
Views: 347, Comments: 14
Last comment 02/21/2018 by artsmith
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Challenge Questions

361 blog entries, 28827 comments (0 Viewing)

Electric Bill Enigma: Newsletter Challenge (February 2018)

This month's Challenge Question: Specs & Techs from GlobalSpec: A family moves into a new house in December and notices a musty smell in the base...
Views: 1935, Comments: 41
Last comment 02/07/2018 by dkwarner

Fuddled Frequencies: Newsletter Challenge (January 2018)

This month's Challenge Question: Specs & Techs from GlobalSpec: Suppose your preferred AM radio station is located at 800 kHz on your radio dial,...
Views: 2504, Comments: 176
Last comment 01/23/2018 by dkwarner
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TechnoTourist’s Engineering Expeditions

87 blog entries, 569 comments (0 Viewing)

Solar Power in Greece: Stalled but not Out of Gas

12/19/2017 by BestInShow
As we passed through residential suburbs on the way from the airport to downtown Athens, I noticed that many of the rooftops sported solar hot water t...
Views: 320, Comments: 0

Say It Isn't So! Greek Theater Acoustics Aren't Perfect

11/15/2017 by BestInShow
Have you ever heard that Greek theaters, at least some of them, had such perfect acoustics that the audience could hear a word whispered from the orch...
Views: 425, Comments: 33
Last comment 12/11/2017 by truth is not a compromise
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Abe's Blog

8 blog entries, 248 comments (0 Viewing)

German Christmas Markets

12/04/2017 by amichelen
We are about to start the 2017 holiday season, and I would like to talk about it. Since my childhood I have always enjoyed the beauty of these days: t...
Views: 338, Comments: 29
Last comment 12/12/2017 by James Stewart

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: 2694, Comments: 125
Last comment 08/14/2017 by amichelen
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"On This Day" In Engineering History

244 blog entries, 847 comments (0 Viewing)

September 27, 1998 – The (Sort of) Birthday of Google, Inc.

09/27/2017 by MaggieMc
When I chose September 27 to investigate for engineering developments of historical import, I was surprised to find Google’s birthday on the lis...
Views: 307, Comments: 3
Last comment 10/03/2017 by Brave Sir Robin

September 4, 1926 – The Death of Julia Brainerd Hall

09/04/2017 by MaggieMc
On September 4, 1926, Julia Brainerd Hall, who assisted her brother Charles Martin Hall in producing the first samples of man-made aluminum in 1886, d...
Views: 378, Comments: 2
Last comment 09/07/2017 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: 566, 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: 556, 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: 314, 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: 308, 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: 1036, 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: 214, Comments: 1
Last comment 04/17/2017 by James Stewart
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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: 413, 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: 169, 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: 746, Comments: 11
Last comment 03/16/2017 by James Stewart
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The CR4 Admin Blog

101 blog entries, 1495 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: 666, Comments: 16
Last comment 03/09/2017 by jdretired
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Other Blog Entries of Interest

Caption This for 02/09/2018

02/09/2018 posted in Caption This!
by lmno24
Here's this week's image! I actually found this online the other day and it seemed fitting give that today is National Pizza Day. As always, be sur...
Views: 511, Comments: 26
Last comment 02/14/2018 by MR. Guest

Flight Bow Shooting Machine

01/24/2018 posted in Workbench Creations
by Del the cat
I've been messing around with flight bows and their arrows for some time and it's virtually impossible to get consistent test results. There are so m...
Views: 598, Comments: 24
Last comment 01/28/2018 by Del the cat

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: 692, 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: 827, 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: 529, Comments: 20
Last comment 03/20/2017 by Mikerho