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What are these banded earthworks near a freeway overpass for and what are they called?
The satellite view of this overpass (on Google Maps) shows some banded earthworks.
When driving by, you can see that each band is an elongated triangular shape (street view):
My guess is that these earthworks act as a wind break by making the…
CJ Dennis
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What drives improvements in seismic safety?
I get the impression that a lot of old buildings fail to meet modern earthquake safety norms, and need to be rebuilt or retrofitted. But what has changed in the last few decades that would make a building constructed today better than an older…
200_success
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Calculation of the specific CO2 emission of a cogeneration plant for the produced electricity
Suppose I have a cogeneration plant that runs on natural gas and produces heat and electricity. The heat effeicieny is $\eta_{th} = 0.4$ and the electricity efficiency is $\eta_{el} = 0.4$.
The burning of natural gas produces 215 g/kWh of CO2.
For…
Emma
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Light signal isolation
It is possible with a microphones array to isolate a sound coming from a direction. Is it possible with an array of photo diodes to isolate a light signal coming from one direction?
For example having 4 photo-diodes oriented at the same direction,…
Mehdi
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Shear Force Distribution on disk
I have to solve the differential equation for radial disks, and therefore I need the shear force distribution. The disk is rotationally symmetric.
I want to use the superpositions principle and set 3 areas.
$0 \le r \le D_i / 2$
$D_i / 2 < r \le…
idkfa
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5
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Heat transfer coefficient of a cylindrical hot water storage tank depending on its size
I have a simulation model of a cylindrical hot water storage tank. The heat loss is determined by the surface area and the heat transfer coefficient.
A configuration of the storage tank with 900 liters was validated with a real scenario.
Now I…
MerklT
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5
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What does 'Open Flow' mean for a pump flow rate?
I have specifications for a positive displacement pump where, in the data table on the last page, the given flow rate is referred to in the column header as 'Open Flow.'
Is this the maximum flow generated by the pump?
James Izzard
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How can I calculate the power and torque required for the motor on a wheeled robot/vehicle?
How can I calculate the power and torque required for the motor on a wheeled robot or vehicle if a particular acceleration or movement up an incline is required?
DKNguyen
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Calculating shaft diameter
I'm designing a circular shaft that's going to carry a spread radial load of about 200kg and also transmit a 160Nm torque. I'm not very familiar with materials but what I'm guessing I'll be able to get at a reasonable price locally is some lower…
php_nub_qq
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When can the effect of self-weight be neglected?
When studying the strength of materials at the introductory level, we often make five simplifying assumptions.
Material is homogeneous and isotropic.
Material obeys Hooke's law
Body is assumed to be prismatic
Effect of self-weight is…
M.Tarun
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5
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Solar powered kettle - how much power for 1/2 litre
I want to create a solar powered kettle but first, I need to know how much power will be required.
This means, I think, I'll need to know how much water I want to bring up to a certain temperature.
I'm trying to understand how to work this out,…
MyDaftQuestions
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5
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2 answers
Applications of Five-Bar Mechanisms
I have some university work to do based on a real world application with five or six bar mechanism, but I am unable to find such a device. Are there real applications of such mechanisms? I've considered some, such as the trigger of a gun and a…
Alessandro Nardinelli
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5
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2 answers
What's the difference between annealing, curing and sintering?
All these processes sound like structural change caused by heating.
Sparkler
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4 answers
How to compare utilization rates?
I have the utilization rates of several machines for each week over a year. These differ per week because of the occurrence of machine failures and changes of orders. Meaning that one week a machine could be a bottleneck and the other week not. I…
user78820
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What grade of Neodymium magnets are commonly used in hard drives?
I want to buy some magnets, but the ones that I have found on online shops are mostly grade N38. They are pretty cheap, but they need to be as strong as the ones found in a hard drives. I am afraid hard drive magnets are N52 (or at least a higher…
77120
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