Learning a MVC framework : laravel 5

July 3rd, 2015 No comments

Some useful links:

http://laravel.com/docs/5.0/helpers#urls

call custom files (php or otherwise) into a laravel project. For me app.php file to which I added

'Helpers'   => 'app\TradeLogic\engine'

was in config/app.php

The app.php file didn’t help.

What actually worked was adding :

include_once (__DIR__.'/../resources/views/engine.php');

to the file bootstrap/autoload.php
The path shown is from the location of the autoload file.

 

Migrations

To drop a column, need to run “composer require doctrine/dbal” otherwise a rollback that drops a column will fail.

If the filename of a migration got changed, or it got deleted, the ‘php artisan migrate’ command will complain. Need to run ‘composer dumpautoload’ shich will fix things.

Categories: Web development Tags:

Casting aluminum

June 18th, 2015 No comments

Interesting thread on Casting Strength found here.
Excerpts:

Now, if you want to experiment with casting an alloy of ths type, here’s how to get out cheap;-) Find somebody who does punch work and ask them to save the slugs for you. I have a 5 gal bucket of 3003 slugs that are 3/8×3/4″ ovals, punched out at a buddy’s shop. It is the perfect size for the crucible, doesn’t require breaking up, melts really fast, and being a weldable alloy, it flows and pours like you wish everything would.

Once cast, it machines just like 3003; soft, gummy, and gooey. It makes very solid castings using the lost foam process in dry sand. Much better than scrap waterpump housings and old VW pistons. That may be the best alloy for you to use, actually. It’s soft enough to avoid cracking and, as we all know is just rediculously easy to weld. It’s not as strong as 6061, but you’ll have a really tough time making a set of castings up that will mate well under load with 6061 T6 without the casting being as big as the engine block.

and

I worked for a few years with two guys who built custom racing bike frames as a side business. Short of going to graphite composite, their preference was alloy steel tube that was silver sodlered at the joints. They used reinforcement at joints by using two tube sizes that nested and put on a tube seat of the larger tube and then inserted in the frame member to get a double wall at structural joints. They also used swaged tube that was thinner wall at midspan and heavier wall at the tube joints. The swaged tube was strictly special order only.

the reason for using silver solder was to avoid destroying the wrought grain structure at the joint. TIG welding would change the grain structure from wrought to cast structure where the metal melted, making a much weaker joint.

From experience with truck frames in the 70’s, aluminum is no substitute for steel. Aluminum truck frames were made to reduce weight and increase payload in log and flatbed trucks. However, the aluminum frames inevitably cracked and had to have reinforcing plates installed, which made the frame heavier than the steel version and still prone to cracking. It is also much less stiff than steel by a factor of at least 3.

Last thing, 6061-T6 is cast, wrought, solution annealed and then precipitation hardened. The grain structure is not quite cast, but some of the wrought structure goes away during the solution anneal. Casting 6061-T6 with a precipitation hardening process won’t be quite as strong as the T6 processing, but will be better than as-cast and will machine better. There is another type of processing, T8, which is cast, wrough, solution annealed, wrought again and then precipitation hardened which comes out stronger and harder than T6, but no stiffer.

Categories: Engineering Tags:

kvm localized virtual desktops

May 7th, 2015 No comments

I read something interesting the other day. Running multiple VMs, on the same computer; the catch is that they are all running on the same desktop (not headless) sharing one display. The term is “kvm localized virtual desktops”.

The place I read this was the UnRaid blog, talking about KVM integration into the UnRaid 6 system (SOURCE).

Since OpenSuSE has tools and support for kvm, I shall try this.

It would be interesting to run linux and windows and not have to dual boot, and have access to the same GPU from both OSs.

Categories: Linux Tags:

space usage

May 7th, 2015 No comments

Recently came across one of my linux VM machines that ran out of disk space. But where did all the space go? What ate it up?

du -h <dir> | grep ‘[0-9\.]\+G’

This will list a sorted view of the foles/folders from largest to smallest.

(SOURCE)

Categories: Linux Tags:

Accessing network drives from command prompt

April 27th, 2015 No comments

Oddly enough on windows you can’t just type R:/ in the cmd prompt and change directory there. That syntax only works for local drives.

You have to type /Df:\ to open the f: drive

Categories: Computer geek stuff Tags:

Laser Diffraction pattern research

February 26th, 2015 No comments

Found a few sites/companies that manufacture difracion gratings. I should contact them and get some samples.

http://worldstartech.com/products/description/60/index

http://www.lasercomponents.com/us/product/pattern-generators-for-flexpoint-laser-modules/

http://www.edphoton.com/Other%20Standard%20DOEs%20English.htm

Categories: Engineering Tags:

Strenghtening 3d printed parts

February 16th, 2015 No comments

Some interesting and some common ways to make 3d parts stronger.

http://st3p3d.com/blogs/3d-printing/14992261-a-few-ways-to-strengthen-3d-printed-parts

Categories: 3D printing Tags:

OpenCL in Linux

December 24th, 2014 No comments

I was evaluating the demo version of Agisoft PhotoScan and I could not the OpenCL option to show up in the software’s preferences.
After installing the python OpenCL libraries, PhotoScan was able to detect the GPU and gave me the OpenCL option.

Categories: Computer geek stuff, Linux Tags:

CATIA STL to surfaces

December 16th, 2014 No comments

Categories: Uncategorized Tags:

Network storage and backup

November 28th, 2014 No comments

I lost a HD the other day and whatever data was on it. I think I had most things backued up but there was still some data that is gone forever. This got me thinking about how to better protect ALL devices in my house.

Storage is cheap, but I don’t want 2 HD in every machine. And some machines like the laptops can’t use 2 HDs.

At the same time I need to re-evaluate the NAS solution in my house. I’m currently managing two systems. An UnRaid computer for archival storage and a Nas4Free machine for a faster access of data.

Steps:

1. Add an SSD drive to UnRaid as a cache drive to speed up write functions on the UnRaid system, and compare network read/write speeds with the Nas4Free box. See how different the two really are.

2a. If speeds are very close, take apart the Nas4Free array and move the two 2TB drives to the UnRaid system.

2b. If speeds are not close buy two 2TB drives and replace the two 1TB drives in the UnRaid system. This will increase the array capacity by 2TB.

3. For all computers set up some software that will backup the working files of all computers to a backup folder on the UnRaid system. Have this backup be done once a day (probably at night). A scheduled rsync operation (that also mirrors deleted files) should suffice. I don’t want an ever growing amount of data. Just a mirror copy of the machine’s HD in case it fails.

Categories: Computer geek stuff, UnRAID Tags: