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General Discussion

15548 threads, 293245 comments (10 Viewing)

Drone uses

01/20/2018 by ronseto
The use of drones along our southern border is the best use so far. Drones, once thought of as toys, have proven their real worth. they are used by ou...
Views: 8, Comments: 3
Last comment 01/20/2018 by Rixter


01/20/2018 by Ukeje
Thank you honorable members. Let us have access to the wiring diagram of Mitsubishi ME222389, MITSUBISHI FUSO TRUCK BUS CO ME225157 ORDER NUMBER 02810...
Views: 16, Comments: 2
Last comment 01/20/2018 by SolarEagle

Wind Load for ISO Shipping Container

01/20/2018 by Jazzman
Hi All , I need help calculating mph wind load to overturn a 20 ft and a 40 ft shipping container with the following specs. 40 ft -- 8ft wide 9.5 ft t...
Views: 30, Comments: 4
Last comment 01/20/2018 by Jazzman

Train Brake System vs Semi Systems

01/20/2018 by HiTekRedNek
On a semi tractor trailer,the brakes are applied by default if air pressure fails. Air pressure is required to release the brakes,but on trains,air i...
Views: 46, Comments: 9
Last comment 01/20/2018 by TonyS
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Commercial Space

2015 threads, 3839 comments (2 Viewing)

Calling For: Slurry Wall Solutions

01/19/2018 by HSL
Abstract Slurry cut-off walls are increasingly being used to control groundwater flows for geo-environmental or geotechnical purposes. The most impor...
Views: 35, Comments: 4
Last comment 01/19/2018 by Mikerho

Hastelloy C276 Buttweld Fittings

01/15/2018 by siddhagiri
Hastelloy C276 Buttweld Fittings is most common pipe fitting elbow.ASTM B366 Hastelloy C276 Buttweld Fittings can connect various sizes of pipes toget...
Views: 33, Comments: 1
Last comment 01/15/2018 by lyn

What Kinds of Materials Should be Prepared for Protein Structure Analysis?

12/24/2017 by joannabowie
What kinds of materials should be prepared for protein structure analysis?
Views: 94, Comments: 0
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CR4 Feedback

698 threads, 12120 comments (0 Viewing)

What Happened to Some of Our Great Members? Sparkstation and Masu Come to Mind

01/13/2018 by Andy Germany
Over the last 10 years or so, we seem to have lost some really great members, they have gone without saying goodbye as far as I remember, which is pro...
Views: 174, Comments: 15
Last comment 01/16/2018 by JE in Chicago

What Happened to Emailed Notifications of New Posts?

01/05/2018 by James Stewart
I have received no new post notifications in this last week.
Views: 100, Comments: 13
Last comment 01/16/2018 by James Stewart
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Section Blogs

WoW Blog (Woman of the Week)

206 blog entries, 579 comments (0 Viewing)

Woman of the Week – Florence Nightingale

01/16/2018 by lmno24
Florence Nightingale was a social reformer, statistician and likely most known as the founder of modern nursing. Her work is going to be showcased in...
Views: 197, Comments: 4
Last comment 01/17/2018 by James Stewart

Woman of the Week – Natasha Baker

01/08/2018 by lmno24
I came across this article on our main site, Electronics 360, and thought this lady would be a good one to feature on CR4! We were able to interview N...
Views: 258, Comments: 0
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The Engineer's Notebook

457 blog entries, 7511 comments (0 Viewing)

The High-tech Skin Care Aisle

01/20/2018 by M-ReeD
When I imagine the latest in electronic innovation being unveiled last week at the Consumer Electronics Show (CES) in Las Vegas, I didn’t exactl...
Views: 26, Comments: 0

Hitting the Facebook "Snooze" Button

01/13/2018 by M-ReeD
Find that you need a break from the nonsense that is Facebook? With its timely updates about what people are doing, not doing, eating, watching, think...
Views: 211, Comments: 13
Last comment 01/18/2018 by James Stewart
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Challenge Questions

360 blog entries, 28774 comments (1 Viewing)

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: 1644, Comments: 164
Last comment 01/20/2018 by dkwarner

Stumped by the Screen: Newsletter Challenge (December 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: Viewing a common LCD display from straight on, you see a figure in pink. Tilting...
Views: 761, Comments: 16
Last comment 12/07/2017 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: 281, 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: 399, 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: 303, 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: 2323, 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: 253, 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: 361, 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: 527, 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: 538, 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: 278, 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: 282, 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: 998, 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: 198, 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: 378, 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: 155, 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: 703, 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: 330, Comments: 15
Last comment 02/05/2017 by JPool
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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: 629, Comments: 16
Last comment 03/09/2017 by jdretired
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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: 711, Comments: 9
Last comment 02/07/2017 by ronc
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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: 667, 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: 800, 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: 506, 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: 625, 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: 729, Comments: 52
Last comment 03/10/2017 by MaggieMc