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13389 threads, 236582 comments (15 Viewing)
 

Light Energy Puzzle

11/26/2014 by G.K.
Hello everybody. I was wondering what will happen if we insert light energy in a closed system continuously. E.g. look at my next drawing: A laser...
Views: 210, Comments: 28
Last comment 11/27/2014 by G.K.
 

Rubber Tube Contraction Velocity

11/25/2014 by HiTekRedNek
Assume that you have 2 rubber tubes,of equal diameter and wall thickness,made of the same material,natural rubber. They have the same stretch force...
Views: 190, Comments: 23
Last comment 11/27/2014 by geraldpaxton
 

Micro Motion Sensors

11/25/2014 by classic1911
I'd like thoughts on micro motion sensors that can be attached to items and alert on smart phone when moved...
Views: 117, Comments: 10
Last comment 11/26/2014 by redfred
 

Force in Space

11/25/2014 by Abhishek Rock
if we forcing two body with a same force in space, if its move then what is the velocity of these two body( both bodies have diffrent mass )
Views: 272, Comments: 34
Last comment 11/27/2014 by TrevorM
 

Prop Drag on a Sailboat Motor

11/24/2014 by bud short
I have a battery powered trolling motor assisting a small sailboat. Its prop remains in the water at all times. Let's say with no friction (i.e., in a...
Views: 238, Comments: 11
Last comment 11/25/2014 by lyn
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Commercial Space

1827 threads, 3343 comments (3 Viewing)
 

EPC Contract.

11/25/2014 by Anonymous Poster
Hi, Condition of contract for electrical and mechanical works including erection at site (1987) was in place earlier, and revised in 1999 suite - but...
Views: 11, Comments: 0
 

Are SEO Mistakes Costing You Money?

11/21/2014 by meganfoster
As an affiliate marketer, you'll want to make sure you do everything possible to increase your search rankings on websites such as Google. The higher...
Views: 24, Comments: 1
Last comment 11/21/2014 by Tornado
 

BAE Systems - Online Career Event, 24th - 30th November - Engineering experience

11/20/2014 by btbsilent
Seize once-in-a-lifetime opportunities to work on the biggest challenges and best technologies. From complex engineering projects to effective bus...
Pathfinder Tags: engineering jobs safety
Views: 78, Comments: 1
Last comment 11/21/2014 by Anonymous Poster
 

LED Lighting "Money King" Bright

11/19/2014 by xlxled
From the perspective of the promotion of LED lighting development policy, the local government in response to the call of the nationalenergy-saving...
Pathfinder Tags: LED LED Lighting
Views: 26, Comments: 1
Last comment 11/19/2014 by europium mkII
 

The Rapid Development of LED Module

11/18/2014 by xlxled
Energy saving, environmental protection, high efficiency LEDmodule, long life, easy to use, not only by the field Home Furnishingdecoration welcome...
Pathfinder Tags: led LED module
Views: 19, Comments: 0
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CR4 Feedback

607 threads, 10647 comments (0 Viewing)
 

Annoying Header

11/19/2014 by lyn
This half page header now comes up at the top of every home window that opens. Community * All * News & Analysis * Products & Supplie...
Views: 99, Comments: 6
Last comment 11/20/2014 by lyn
 

Quality of Forum Replies

11/12/2014 by roeblinggrid
I recently replied to a post in the "Engineering Careers" section and felt that it should be repeated here so I will adapt my reply into a post in the...
Views: 1732, Comments: 53
Last comment 11/17/2014 by Nigh
 

Posting Pictures

11/03/2014 by texasron
I use to be able to post pictures, now I cant. I need to post to bring up a problem with surface pits in continuous steel castings. any help? Thanks...
Views: 228, Comments: 10
Last comment 11/04/2014 by geraldpaxton
 

Locked Out Again

11/02/2014 by lyn
You (or someone else on the same network) has done this operation too many times. You will have to try again tomorrow. Sorry for the...........
Views: 109, Comments: 4
Last comment 11/13/2014 by jdretired
 

Matter to be Looked at By CR4 Admin

10/31/2014 by dhayanandhan
This about CR4 Good Answers, which I raised about a year back, and to-day's problem is similar to that. Whether my answer is Good Answer or not, I ha...
Views: 138, Comments: 4
Last comment 10/31/2014 by Fredski
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Section Blogs

Caption This!

284 blog entries, 12252 comments (0 Viewing)

Caption This for 11/21/14

11/20/2014 by Kaplin
This week's image: Be sure to vote for your favorite caption! Thanks to europium mkII for submitting this image.
Pathfinder Tags: Caption this engineering images funny images writer's block
Views: 602, Comments: 53
Last comment 11/24/2014 by Unredundant

Caption This for 11/14/14

11/14/2014 by Kaplin
This week's image: Be sure to vote for your favorite caption! Thanks to BruceFlorida for submitting this image.
Pathfinder Tags: Caption this dragonfly engineering images funny images thunderbird
Views: 599, Comments: 20
Last comment 11/18/2014 by Rixter

Caption This for 11/07/14

11/06/2014 by Kaplin
This week's image: Be sure to vote for your favorite caption! Thanks to Nigh for submitting this image.
Pathfinder Tags: Caption this chainsaw engineering images funny images
Views: 697, Comments: 53
Last comment 11/13/2014 by luyombya
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The CR4 Admin Blog

68 blog entries, 1064 comments (2 Viewing)

Engineering News Blog Retired, New Feed to Engineering360 Launched

11/20/2014 by SavvyExacta
By now you're probably familiar with CR4's new look following the launch of IHS Engineering360 in September. In case you missed it, read my overview h...
Views: 153, Comments: 9
Last comment 11/21/2014 by HUSH

IHS Engineering360 Tour

10/02/2014 by SavvyExacta
IHS Engineering360 launched one week ago. The new site is a great resource for engineers because it offers supplier and part search, daily news and...
Views: 221, Comments: 0

Changes to CR4 Navigation

09/25/2014 Welcome to the new IHS Engineering360! As you can see, there have been some slight changes to the navigation on CR4. Check out the graphic and explana...
Views: 441, Comments: 15
Last comment 09/29/2014 by Wrench twirler
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The Engineer's Notebook

326 blog entries, 5360 comments (1 Viewing)

Lifecycle of The Mayflower

11/26/2014 by HUSH
As has become CR4 happenstance, I am one of the last ones to post before Thanksgiving. To be honest, I'm not in the office this Wednesday and haven'...
Pathfinder Tags: Mayflower Thanksgiving transocean voyage
Views: 87, Comments: 3
Last comment 11/27/2014 by vsar

Skyney is Coming, No Really (Technological Singularity)

11/19/2014 by HUSH
Last spring I was on vacation in Florida and took the hour drive from the beach into Orlando to visit Universal Studios. Many people elect for one o...
Pathfinder Tags: Singularity technology Terminator transhuman
Views: 183, Comments: 15
Last comment 11/21/2014 by europium mkII

Engineering Degree? Your 'Get Out of Jury Duty Free' Card

08/20/2014 by HUSH
Jury duty is often described as a consequence of citizenship. "It's a civic duty!" and "Give back to your community!" are two of the more guilt-lace...
Pathfinder Tags: career engineer jury duty
Views: 803, Comments: 42
Last comment 08/26/2014 by adreasler
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The Standard

4 blog entries, 12 comments (0 Viewing)

New ISO Energy Management Standard Released

11/18/2014 by KevinCassidy
The International Organization for Standardization (ISO) has released the new ISO 50003:2014 Energy management systems - Requirements for bodies provi...
Pathfinder Tags: ANSI audit certification Energy energy standards ...
Views: 84, Comments: 0

Follow up: Women's Lacrosse Headgear Standard Set for Second Ballot

11/13/2014 by KevinCassidy
I wrote about the debate between the Florida High School Athletic Association and US Lacrosse over the use of helmets during high school girls lacross...
Pathfinder Tags: ANSI ASTM eye protection face florida ...
Views: 90, Comments: 0

Don't Forget to "Look Before You Pump"

11/05/2014 by KevinCassidy
The Outdoor Power Equipment Institute (OPEI) has been active in educating consumers about the variety of fuels available at the pump, and how to ident...
Pathfinder Tags: ANSI automotive E10 E15 equipment ...
Views: 185, Comments: 8
Last comment 11/08/2014 by tcmtech
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Challenge Questions

321 blog entries, 27369 comments (1 Viewing)

Icy Imbalance: Newsletter Challenge (November 2014)

11/01/2014 This month's Challenge Question: Specs & Techs from IHS Engineering360: The two poles of the Earth contain ice. Why does Antarctica have much mo...
Pathfinder Tags: challenge questions
Views: 2811, Comments: 20
Last comment 11/26/2014 by MOBI

The Merlin Rocket Engine: Newsletter Challenge (October 2014)

10/01/2014 This month's Challenge Question: Specs & Techs from IHS Engineering360: The SpaceX Falcon 9 v1.1 uses nine Merlin 1D rocket engines in its first...
Pathfinder Tags: challenge question
Views: 2592, Comments: 46
Last comment 10/28/2014 by HiTekRedNek

Balloon Ride: Newsletter Challenge (September 2014)

09/01/2014 This month's Challenge Question: Specs & Techs from GlobalSpec: You are inside a car with the windows closed, and you are holding a helium ballo...
Pathfinder Tags: challenge question
Views: 4143, Comments: 40
Last comment 09/23/2014 by redfred
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OH CR4P!

61 blog entries, 516 comments (1 Viewing)

Safety Concerns of Oil by Rail

10/30/2014 by cheme_wordsmithy
Historically, most oil in the U.S. has been transported via pipeline. In 2008, the U.S. saw the rise of a new alternative for crude oil shipment - rai...
Views: 299, Comments: 18
Last comment 11/03/2014 by Lynn.Wallace

Dangerous Drilling - Oil & Gas Rig Safety

03/06/2014 by cheme_wordsmithy
Crude oil and natural gas have over the last hundred plus years become critical to our way of life and economy. Not only do they satisfy a huge chun...
Views: 575, Comments: 2
Last comment 03/06/2014 by texasron
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Roger's Equations

90 blog entries, 1136 comments (0 Viewing)

Moore's Not Enough: The Future of Computing by Roger Pink

10/15/2014 by Roger Pink
Moore's Law Gordon E. Moore, in his 1965 paper entitled "Cramming More Components onto Integrated Circuits" made the observation that the number of c...
Views: 308, Comments: 1
Last comment 10/16/2014 by SimpleMind

Delicate Audacity: The Saturn V Rocket by Roger Pink

09/25/2014 by Roger Pink
"It was quite a monster to ride. It had a total of seven and a half million pounds of thrust, and the first stage burned four million pounds of pr...
Views: 507, Comments: 16
Last comment 09/30/2014 by Wrench twirler

Why LiFi? by Roger Pink

05/08/2014 by Roger Pink
The Coming Data Crunch Everywhere you look nowadays, the world is becoming more mobile. Smart phone...
Views: 645, Comments: 2
Last comment 05/09/2014 by Rixter
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Defense & Security Technology

77 blog entries, 1168 comments (0 Viewing)

Syrian Chemical Weapons Destruction Problematic

09/25/2014 by IHS GlobalSpec eNewsletter
A recent U.S. statement said Syria could have withheld some of its chemical weapons from destruction. While the stocks turned over have been destr...
Views: 233, Comments: 2
Last comment 09/29/2014 by Wrench twirler

China's Hong Kong Listening Post Revealed

08/24/2014 by IHS GlobalSpec eNewsletter
The purpose of a geodesic dome atop Hong Kong's highest mountain was unveiled recently in IHS Jane's Defence Weekly. The facility has been operating...
Views: 500, Comments: 8
Last comment 08/25/2014 by Unredundant

Sea Drone is Solar Powered

07/03/2014 by IHS GlobalSpec eNewsletter
Eco Marine Power's Aquarius USV (unmanned surface vessel) will be a trimaran covered with "marine grade" solar cells to charge its Li-ion batter...
Views: 440, Comments: 7
Last comment 07/08/2014 by europium mkII
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Physics In Film

9 blog entries, 85 comments (0 Viewing)

Medieval Physics - Siege Engines

09/03/2014 by cheme_wordsmithy
I don't think a blog series titled Medieval Physics would be complete without a discussion of siege engines. Siege engines were the machines that made...
Views: 443, Comments: 10
Last comment 09/09/2014 by SavvyExacta

Medieval Physics - Jousting

08/26/2014 by cheme_wordsmithy
In a previous blog entry I gave a short summary of the physics and history of the bow and arrow (thanks to all you CR4 users who shared your insight a...
Views: 381, Comments: 8
Last comment 08/29/2014 by phoenix911

Medieval Physics - Bows & Arrows

08/12/2014 by cheme_wordsmithy
Of the many interesting events that take place in the summer, one of my favorites are Renaissance fairs. Seeing the participants in character and cost...
Views: 534, Comments: 15
Last comment 08/13/2014 by suresh sharma
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Notes & Lines

18 blog entries, 116 comments (0 Viewing)

Acoustic Guitar Tonewoods

07/26/2014 by cheme_wordsmithy
I remember the day I received my acoustic guitar, and played it for the first time. In the moment, it seemed produced the most beautiful sound I had e...
Views: 430, Comments: 14
Last comment 08/06/2014 by Holzfeller

For Love of the Index

05/09/2014 by Hannes
If you're a literate human who's a (diligent) knowledge worker or (diligent) student, chances are you've used an index this week. Or at least you di...
Pathfinder Tags: books index indexing
Views: 330, Comments: 0

Wait...What'd I Just Say?

03/27/2014 by Hannes
Several months ago, an acquaintance decided to try out a speech recognition software program to cure writer's block. He found it to be quite "inte...
Pathfinder Tags: ambiguity natural language processing nlp words
Views: 808, Comments: 8
Last comment 04/02/2014 by Calnet42
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TechnoTourist’s Engineering Expeditions

80 blog entries, 461 comments (0 Viewing)

Vacation Destinations for Engineers

07/17/2014 by SavvyExacta
What are your summer vacation plans? TechnoTourist has compiled a list of some destinations of engineering interest that have been featured on the b...
Views: 510, Comments: 11
Last comment 07/22/2014 by SavvyExacta
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Animal Science

210 blog entries, 1914 comments (0 Viewing)

Ways to Care for Your Aging Cat

06/16/2014 by SwissMiss
One of my most cherished memories is the day I adopted my first cat. My younger self was delighted to have a new friend, and as we grew together ove...
Views: 640, Comments: 8
Last comment 06/20/2014 by SwissMiss

Jeepers, Creepers... a Different Kind of Peepers!

05/01/2014 by SavvyExacta
The birds are singing, the grass is greening, and the peepers are peeping. Spring has finally sprung here in upstate New York after a long, long win...
Pathfinder Tags: ANIMAL SCIENCE frogs hibernation peepers
Views: 537, Comments: 5
Last comment 05/02/2014 by lyn

Would You Do Anything for Love? Cardinals Will!

02/14/2014 by SavvyExacta
As you enjoy your morning coffee you gaze out the window and watch the birds at the feeder. But what's going on in the distance - is something attac...
Pathfinder Tags: bird behavior
Views: 739, Comments: 6
Last comment 02/19/2014 by Doggoneit
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WoW Blog (Woman of the Week)

159 blog entries, 452 comments (0 Viewing)

Women Redefining Leadership in STEM and IT

05/10/2014 by Chelsey H
As of 2014, there is still a lack of female representation in science, technology, engineering, and mathematics. Women hold just about 32 percent of...
Views: 531, Comments: 3
Last comment 05/11/2014 by europium mkII
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What Is It?

60 blog entries, 1628 comments (0 Viewing)

What Is It? for 2/28/2014

02/28/2014 What is this stuff?
Views: 931, Comments: 30
Last comment 03/18/2014 by RufusVS

What Is It? for 2/22/2014

02/22/2014 What is this item? Two views are shown. Share your guesses below!
Pathfinder Tags: What is it?
Views: 1056, Comments: 71
Last comment 03/02/2014 by Andy Germany

What Is It? for 2/15/2014

02/15/2014 What is this? Bonus points if you can guess where it is, too!
Pathfinder Tags: What is it?
Views: 932, Comments: 19
Last comment 03/06/2014 by steven phaneuf
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Great Engineers & Scientists

144 blog entries, 499 comments (0 Viewing)

U.S. Presidents Who Were Engineers

02/16/2014 by SavvyExacta
Monday is Presidents' Day in the USA. In honor of Washington and all other presidents we will take a look at those who contributed something to engi...
Views: 884, Comments: 18
Last comment 02/21/2014 by suresh sharma
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Other Blog Entries of Interest

Are Energized Fluids the Economic Alternative?

10/03/2014 posted in Rockaholic Adventures
by Shawn
Suppliers, researchers, and service companies working in unconventional oil and natural gas plays look to displace large volumes of hydraulic fract...
Pathfinder Tags: energized fluids energized foams energized fracture treatments
Views: 236, Comments: 0

Galactic Puzzle (take 2)

09/23/2014 posted in Relativity and Cosmology
by Jorrie
Galaxies usually occur in galactic clusters or super-clusters, where from a few tens to a few thousand galaxies move in huge orbits around some...
Pathfinder Tags: Expansion rate Hubble flow
Views: 379, Comments: 23
Last comment 09/25/2014 by dkwarner

Do We Live In a White Hole?

08/28/2014 posted in Relativity and Cosmology
by Jorrie
At the event horizon radius of a normal black hole (BH), things 'fall in' at the local speed of light, or more subtly said, "space itself falls in...
Pathfinder Tags: black hole White hole
Views: 511, Comments: 29
Last comment 09/26/2014 by James Stewart

Slo' Mo' Hat Cam

07/04/2014 posted in Workbench Creations
by Del the cat
I wanted to see how my arrows were flying from my bow, specifically flight arrows. A flight arrow presents a conundrum, you'd think you would want...
Views: 770, Comments: 67
Last comment 07/15/2014 by europium mkII

The Poisson Distribution by Roger Pink

02/26/2014 posted in Derivations
by Roger Pink
The Poisson distribution, named for Simeon Denis Poisson, is a discrete probability distribution that expresses the probability of a given number...
Views: 474, Comments: 0

Whistling Walnut!

12/28/2013 posted in Workbench Creations
by Del the cat
What to do with the walnut shells left over from Christmas? Make a whistling arrow . I'd been toying with the idea for ages, and if you try an...
Views: 862, Comments: 33
Last comment 01/02/2014 by artsmith

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