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Dan Alec Yamaguchi
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Dan Alec Yamaguchi

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Simulating network slowness, request delay, etc.

Writing Web components, sometime I have to show a spinner (or other hints) to indicate loading of data (via Ajax). This is usually done by adding a class when loading and removing it when data come.
But to test this can be hard if the server is quite fast and the payload is small.
In the past, I just added a sleep() call in the server, to have time to see the changes in action. But it might not be always possible or convenient.
I just found out a useful little application (for Windows) able to delay (or throttle, etc.) a request, up to 3 seconds: Clumsy is an open-source software, small, without install, and doing well its job.

http://jagt.github.io/clumsy/index.html
clumsy makes your network condition on Windows significantly worse, but in a managed and interactive manner. Introduction. Leveraging the awesome WinDivert library, clumsy stops living network packets and capture them, lag/drop/tamper/.. the packets on demand, then send them away.
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Dan Alec Yamaguchi

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A simple system consisting of a pair of atoms in a two-site “minicrystal” is able to reproduce the physics of a widely used model of electrons in a solid.
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When you think you've had enough sun, you probably move into the shade. But, according to a new study, that might not be soon enough--because it turns out that sun keeps damaging skin for hours after exposure.
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With some straightforward logic, one theorist has shown that macroscopic quantum objects cannot exist if P≠NP, which sud…
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Two photons interact for the first time in fiber optic experiment

Vienna University of Technology (TU Wien) researchers have brought together a pair of photons in the strongest coupling possible during a recent experiment. The interaction was great enough to change the phase of each photon by 180 degrees.

"'It is like a pendulum, which should actually swing to the left, but due to coupling with a second pendulum, it swings to the right. There cannot be a more extreme change in the pendulum's oscillation. We achieve the strongest possible interaction with the smallest possible intensity of light,' Arno Rauschenbeutel of the Institute for Atomic and Subatomic Physics at TU Wien said."

Read More: http://ow.ly/DPdMn
Photo Credit: TU Wien
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Read other messages and engrave your own words to bitcoin blockchain forever.
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Very interesting device that I came across online yesterday. This is Cubli, a mechanical cube that is capable of balancing itself very effectively, and can even "jump up and walk" across surfaces by performing controlled falls.

The Cubli attains it's balance from multiple inertia sensors within the device, the measurements of which are fused to get a sense of angular velocity and tilt of itself on a surface. The hull sensors on it measure the angular velocity of the three reaction wheels within the Cubli. These measurements are used by a nonlinear controller to balance it on a corner, while the angular velocity of the reaction wheels are near zero. This allows the Cubli to balance on the corner even when it is disturbed.

In order to jump up, the reaction wheels spin rapidly to build up angular momentum, then the wheels suddenly brake--causing the momentum to be transferred to the Cubli's body which causes it to pop up without needing assistance from outside the device. These jumps and balances can be put in sequences to make it seem as if the Cubli can actually walk.

Specific information about the device (including multiple videos with explanations and demonstrations):
http://robohub.org/swiss-robots-cubli-a-cube-that-can-jump-up-balance-and-walk-across-your-desk/



General information about angular momentum: http://en.m.wikipedia.org/wiki/Angular_momentum
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One of this century's most significant mathematical discoveries may reduce the number of measuring points to one-sixth of the present level. This means reduced exposure to radiation and faster medical imaging diagnostics.
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very nice
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A team led by the University of Colorado Boulder has discovered an invisible shield some 7,200 miles above Earth that blocks so-called 'killer electrons,' which whip around the planet at near-light speed and have been known to threaten astronauts, fry satellites and degrade space systems during intense ...
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