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Section Forums

General Discussion

15470 threads, 290862 comments (12 Viewing)

HPS Ballast with metal halide bulb

11/18/2017 by Gogirl
I am trying to find information on: I have a P.L. Light Systems Canada, LR48877 Ballast, 490W, 60Hz 5.2 amps (.) 120v, date on it is 1998 i have a 1...
Views: 20, Comments: 5
Last comment 11/18/2017 by SolarEagle

Wind/Solar Combined

11/18/2017 by EZStreet
Would it make economical sense to put solar cells on wind both sides of some turbine blades? With the storage and conversion equipment already instal...
Views: 55, Comments: 8
Last comment 11/18/2017 by redfred

Robotic Toys for Anyone

11/17/2017 by BestInShow
I'm particularly drawn to the one made from a soda can.
Views: 61, Comments: 2
Last comment 11/17/2017 by lyn

A Microengineering Miracle

11/17/2017 by Hannes
I'm a big fan of Great Stuff foam. One thing I always hated about it was that the foam would cure in the straw/can, so if I didn't have enough gaps to...
Views: 102, Comments: 3
Last comment 11/17/2017 by SolarEagle
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Commercial Space

2006 threads, 3818 comments (1 Viewing)

Introduction of New Generation Coal Gangue Mobile Crushing Station

11/16/2017 by dsclaire
The new generation COAL GANGUE MOBILE CRUSHING STATION by Zhengzhou Dingsheng Engineering Technology Co., Ltd, is a new type mobile crushing machine...
Views: 19, Comments: 3
Last comment 11/16/2017 by lyn

IMPANIX - Accounting & Bookkeeping

11/16/2017 by Impanix
Accounting services with bookeeping software We provide you both Accounting software & a dedicated bookkeeper With our web-based software, you c...
Views: 11, Comments: 0

General Introduction of Combined Mobile Crushing Plant

11/16/2017 by dsclaire
Overview of COMBINED MOBILE CRUSHING PLANT Raw materials: Granite, limestone, basalt, shale, pebbles, bluestone, sandstone, carbide, iron ore, copp...
Views: 6, Comments: 0

Top Mobile Marketing Trends To Dominate In 2018

11/02/2017 by Suhasj123
Mobile marketing is a multi-way, digital marketing strategy which aims at reaching a target audience on smartphones, tablets, and any other mobile dev...
Views: 65, Comments: 0
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CR4 Feedback

696 threads, 12091 comments (0 Viewing)

Problem Opening CR4

10/20/2017 by roy hammy
I now get his notice when I open a comment, any ideas. Problem! You are attempting to do (or view) something that is not permitted.
Views: 49, Comments: 5
Last comment 11/11/2017 by John mar
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Section Blogs

TechnoTourist’s Engineering Expeditions

86 blog entries, 558 comments (0 Viewing)

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: 215, Comments: 23
Last comment 11/18/2017 by phoenix911

The Key to Power in Your Hotel Room

11/10/2017 by BestInShow
On my recent trip to Greece I realized how well-trained I am to recycle stuff – soda cans, paper, plastic, stray bits of metal – when I co...
Views: 379, Comments: 18
Last comment 11/15/2017 by James Stewart
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The Engineer's Notebook

448 blog entries, 7407 comments (1 Viewing)

Cutting Wait Times for Restaurants with Google

11/18/2017 by M-ReeD
The geniuses at Google are doing life-saving work. Hear me out. Thanks to them, those of us impatiently loitering around the hostess stands at our f...
Views: 34, Comments: 5
Last comment 11/18/2017 by SolarEagle

Letting Amazon into Your Home

11/11/2017 by M-ReeD
Imagine coming home to a warm pizza or the package you ordered from Amazon already safely tucked away in your home. This latest offering from Amazon i...
Views: 134, Comments: 8
Last comment 11/16/2017 by jhammond
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Challenge Questions

359 blog entries, 28594 comments (0 Viewing)

Flying in the Shadow of the Moon: Newsletter Challenge (November 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: A new supersonic passenger airliner is due to take flight next year. A wealthy fr...
Views: 842, Comments: 16
Last comment 11/07/2017 by Hannes

Mystical Magnetic Fields: Newsletter Challenge (October 2017)

This month's Challenge Question: Specs & Techs from GlobalSpec: As you know, the direction of the Earth’s magnetic field changes with time,...
Views: 2154, Comments: 13
Last comment 10/10/2017 by James Stewart
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WoW Blog (Woman of the Week)

201 blog entries, 575 comments (0 Viewing)

Woman of the Week – Danielle Dy Buncio

11/13/2017 by lmno24
Danielle Dy Buncio is the co-founder and CEO of VIATechnik, a construction and engineering services firm working to make the construction industry bet...
Views: 129, Comments: 0

Woman of the Week – Rosa Sheng

10/23/2017 by lmno24
Rosa T. Sheng, is a senior associate at Bohlin Cywinski Jackson, Founder and Chairperson for Equity by Design, an AIA San Francisco committee. She&...
Views: 189, Comments: 1
Last comment 10/25/2017 by BartCraft
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Abe's Blog

7 blog entries, 219 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: 1703, 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: 184, 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: 339, 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: 458, 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: 515, 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: 219, 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: 232, 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: 921, 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: 182, 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: 320, 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: 139, 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: 627, 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: 311, Comments: 15
Last comment 02/05/2017 by JPool
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The CR4 Admin Blog

101 blog entries, 1494 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: 560, 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: 276, 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: 649, 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: 360, 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: 582, Comments: 2
Last comment 07/11/2017 by esperanzajpalmer
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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: 630, 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: 769, 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: 478, 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: 602, 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: 704, Comments: 52
Last comment 03/10/2017 by MaggieMc