a) Your website is broken. When I check the box that says "Want to track your service ticket status online? Provide a few more details to sign up.", and click "Continue" I get a blank web page rather than a form that allows me to enter more details.
b) The person who delivers parcels to us should be FIRED from their job
Steps to reproduce, EVERY SINGLE TIME:
1) Stay home expecting important delivery
2) listen for knock at the door and / or doorbell
3) leave notes to Please knock / ring doorbell / LEAVE PACKAGE HERE
4) LEAVE THE DOOR WIDE OPEN
* Parcel delivery person knocks and / or rings doorbell and / or leaves package at door and / or delivers package to recipient.
* Parcel NEVER delivered
* Notification not left (sometimes)
WHY IS IT THAT THE CANADA POST DELIVERY PERSON DOES NOT EVEN MAKE AN ATTEMPT TO DELIVER PARCELS? DON'T EVEN BOTHER LOADING PARCELS ONTO THE TRUCK, AND YOU CAN SIMPLY FIRE THE DRIVER.
Hopefully the above should be concise enough to fit within your 1000 character limit (it does, I checked).
A particularly great book at describing GNU Make is Managing Projects with GNU Make, which is published by O'Reilly freely under their Open Books Project. In fact, the book itself is distributed under the GNU Free Documentation License which allows me to redistribute an unmodified version of the documentation.
I took the liberty of assembling all of the individual chapters of this document into one cohesive pdf file with TOC links to individual chapters as well as bookmarks. While there are some particularly advanced topics that I could probably add a section on based on my extensive hacking of The Bionic C Library alone (e.g. the Android Build System, or Nonrecursive Automake), I have not modified the documentation in any way, I have just added meta-information to it*.
Some improvements I could see being made to the meta-information are below.
- inter-section references (i.e. links made to a different section from within the text of another)
- Index links (i.e. links to the exact page for each entry in the index)
If you are able to volunteer to make those improvements and share your changes, I would be happy to redistribute them here.
If you like this book, I encourage you to buy a hard copy, or if you feel like GNU Make has benefitted you enough, please donate to the Free Software Foundation.
*I have added the cover to that file as well, so please inform me if I have in any way violated the spirit of the license and I will remove it.
- Download and uncompress the VMWare image (there is a .vmdk inside the .vmwarevm folder for those who do not use Mac OS X / VMWare Fusion)
- Run the VMFlexArrayLinux virtual machine
- Log in with user 'root' and an empty password
- Run 'ifconfig eth0' and write down the IP address
- Open a terminal session on the host OS and ssh into the IP address from above (i.e. ssh root@[ip_addr])
- run the demo ./fb4jdemo
- MappedByteBuffer.hurray()!: Programming the Linux FrameBuffer in Java & VMFlexArray Explained. See here.
- Internet of #allthethings: Using GNURadio Companion to Interact with an IEEE 802.15.4 Network. See here.
What I mean by that, is that when the VM instantiates an integer array object, e.g. int x = new int[ length ], it typically allocates memory (now careful, I'm going to use some C teriminology here) for an object struct (2 uintptr_t in JamVM) which represents the instance of the int object, followed by 1 uintptr_t, which represents the length of the int object, followed by exactly length uintptr_t items (on a 32-bit machine) or length / 2 uintptr_t items (on a 64-bit machine) to represent the data.
VMFlexArrays are slightly different. For the same case as above, where a new int is allocated on the Java heap, the VM would allocate an object struct (2 uintptr_t in JamVM) which represents the instance of the int object, followed by 1 uintptr_t to represent the length of the int object, followed by 1 uintptr_t to point to the int data, followed by the data itself.
What makes VMFlexArrays different, and what makes them flexible (and arguably way better than what most JVMs use today) is that they include that extra uintptr_t to point to the data which could exist anywhere in virtual memory. That means, obviously, VMFlexArrays can point to contiguous data that the JVM would allocate for a regular array, but it also means that it can point to an arbitrary location - and still cooperate with the garbage collector. Indeed, the object lifecycle remains unchanged for VMFlexArrays if the garbage collector avoids releasing memory regions with free(3) if the VMFlexArray pointer does not point to the next contiguous memory address.
VMFlexArray is a solution I came up with that allows one integrate off-heap memory regions into the Java Virtual Machine - e.g. a native external thread that allocates memory using malloc(3), or pages mapped from a device such as /dev/video0 using mmap(2).
Perhaps the aspect of VMFlexArrays that I found most useful, that I somehow forgot to mention during my talk, is that they rather trivially allow the following code snippet to work as expected. Specifically, an IntBuffer derived from a ByteBuffer with a backing array should be able to provide an int backing array view of the same virtual memory.
Currently this code, which should work pretty seamlessly, fails miserably.
With VMFlexArrays, that problem is solved.
I've even used this code to memory map the Linux FrameBuffer and animate a bunch of bouncing balls :-) It works quite well.
There's even a massive speedup associated with access to the underlying byte from a ByteBuffer and even more so viewing the ByteBuffer as an IntBuffer, with access to the underlying int.
I am definitely interested in enabling these changes to make it into OpenJDK, and I feel that the community at large would benefit greatly from them. As my time is rather limited these days, I might prefer to mentor a student to make these changes in the Google Summer of Code, 2015, if OpenJDK was a mentoring organization. Otherwise, I would be open to mentoring a student under the umbrella of JamVM or GNU Classpath as a mentoring organization.
- MappedByteBuffer.hurray()! Programming the Linux Framebuffer in Java & VMFlexArray Explained. See here.
- Internet of #allthethings: Using GNURadio Companion to Interact with an IEEE 802.15.4 Network. See here.
- FreakZ: A BSD-licensed ZigBee stack (for non-commercial purposes)
- Easily modified to communicate to a GNURadio device via UDP (github)
- Note: this stack is not certified.
- a great suite of tools to interact with Software Defined Radio (SDR) transceivers
- GNURadio IEEE 802.15.4 Out Of Tree (OOT) module
- gr-ieee-802_15_4 is available today
- based on work originally from UCLA
- unofficially meets all of the mandatory requirements for the IEEE 802.15.4 PHY layer
- meets some of mandatory requirements for the IEEE 802.15.4 MAC layer
- lacking mandatory MAC features such as
- Beacon Management
- Receive Beacons
- Channel Access Mechanism
- Carrier Sense Multiple Access with Collision Avoidance (CSMA-CA)
- ACK Delivery
- Orphan Scanning
- Store One Transaction
To assist would-be developers in overcoming that hurdle, what I have done is simply used my USRP B200 to record real-world 802.15.4 traffic produced from an EM370 in NodeTest mode. This should easily facilitate offline signal processing using e.g. GNURadio (see File Source block), Matlab, Octave, or any other programming language. The block diagram for doing so is depicted below. I have intentionally made all of my variables directly obvious.
The files are listed and described below:
- simply recording a tone at 2420 MHz in the presence of noise
- note: there is a slight frequency offset which will need to be corrected
- a continuous random stream of valid channel symbols
- a stream containing intermittent & full IEEE 802.15.4 frames
- frames are sent once every 25500 us
A Few Notes About the Current State of IEEE 802.15.4 in GNURadioAll of the open-source PHY implementations assume that Symbol and Timing Recovery (STR) is already performed. This is fine for simulation (depicted below).
However, since we already know the preamble of an IEEE 802.15.4 packet in the 2450 MHz ISM region, we are at liberty to implement a more sophisticated coherent architecture in our receiver. Specifically, due to the known preamble, we may use a Correlate and Sync block.
I will be doing a bit more experimenting in the coming days and will post an update once available.
So when I was a teenager (years and years ago), my cousin John Muller & I played with Matt Howatt and a guy from Australia named Miles, and we covered the song Tinfoil by Limblifter. I played the bass, and Matt & John switched up for rhythm & lead guitar for every other song.
Tonight I had the privilege of seeing some of the original band from Limblifter playing in Hamilton.
It was a fantastic experience to be brought back to the music I loved in my youth and continue to love in adulthood.
Particularly, when I used to play this song, I played the bass, and I was certainly happy to meet the new female bass player tonight, who is certainly overqualified for this set. She has an MA I. Music specializing in the double bass. Aside from the cool factor of a 'chick' bassist, she was doing an amazing job with backup (and in some cases, lead) vocals.
This has probably been the best 'feel good' show for me this summer, thus far.
Thanks again to Limblifter for putting on a full energy show!
For anyone who thinks that going vegan is expensive... totally not the case.
If you are vegan and don't already own one, or if you're considering going vegan and have no idea where to start, investment #1 should be a pressure cooker. Not very many people (in Canada?) own one, but they're soooo common in India, and I've got my indian friends to thank for turning me on to mine.
You can buy massive dried bags of lentils of various colours (dal), kidney beans (rajma), chick peas (chana), or black beans for next to nothing. Compare the contents of one bag ($4 maybe?) to the same mass of beans in 20 (?) cans of water for >= $1 each!
And due to the simple equation from high school that most have forgotten, PV=nRT , you can cook dried gram at a much lower temperature if the pressure is increased (V, n, & R are held constant). This saves on electricity (or gas as the case may be). I'll be the first to admit, I used to cook dried beans like a complete idiot and soak them overnight, and then boil them for 5 hours or something. With a pressure cooker, there is no need to soak legumes overnight and cooking them takes about 1 hr. Most importantly, it completely seals in the flavour for whatever meal you have planned: burritos (like me), kaali, masoor, or tadka dal - or good, old-fashioned soups (e.g. lentil, split-pea)!
A nice side effect: dried legumes take far less energy to transport than cans of legumes that are 60% salt and water; you're going green !
Naturally, not everyone has the proper body chemistry to be able to go vegan with great success, but here is one attractive figure that might catch your eye:
Marathon runners should consume about 1.5 grams of protein per kg of body weight per day .
For a 180 pound guy like me (~80kg according to Google's conversion), that's about 50g of chick peas. What is that for a total protein bill per day - about 25¢ ??
Not bad at all :)
 The Ideal Gas Law (Influences amazing things! E.g. how fast a pot of water takes to boil)
 Vegetarian Diets Help Protect the Environment
(As if you didn't already know how green a vegan diet is!!)
 Sources of Protein for Runners: Spring Marathon Training Plan Part 5