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author | bnewbold <bnewbold@eta.mit.edu> | 2008-11-25 18:21:09 -0500 |
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committer | bnewbold <bnewbold@eta.mit.edu> | 2008-11-25 18:21:09 -0500 |
commit | a2574206f1150354083df6c43506b40429efc9a4 (patch) | |
tree | efa6c7ffdc460408bbab6bcd5a698a263a114695 /tmp | |
parent | 7fb2bedfc29bb6a52520f280ce73b7491e071740 (diff) | |
download | knowledge-a2574206f1150354083df6c43506b40429efc9a4.tar.gz knowledge-a2574206f1150354083df6c43506b40429efc9a4.zip |
adding CS notes, made tmp directory for new, misc, and incomplete items
Diffstat (limited to 'tmp')
-rw-r--r-- | tmp/SCUBA | 83 | ||||
-rw-r--r-- | tmp/Saccade | 7 | ||||
-rw-r--r-- | tmp/Teaching CS | 97 | ||||
-rw-r--r-- | tmp/Topics of Curiosity | 50 |
4 files changed, 237 insertions, 0 deletions
diff --git a/tmp/SCUBA b/tmp/SCUBA new file mode 100644 index 0000000..84d1345 --- /dev/null +++ b/tmp/SCUBA @@ -0,0 +1,83 @@ +============
+SCUBA Diving
+============
+---------------------------------------------
+Self Contained Underwater Breathing Apparatus
+---------------------------------------------
+
+SCUBA stands for "Self-Contained Underwater Breathing Apparatus".
+One of the primary organization regulating recreational SCUBA diving is
+PADI (the Professional Association of Diving Instructors).
+
+Equipment
+---------
+
+:BCD: The buoyancy control device is basically an inflatable live vest
+ that you can inflate using the regulator (or by mouth) to control
+ your buoyancy. Your buoyancy changes as you use up air (tank gets
+ lighter for same volume displaced), inhale/exhale, swim in water
+ of different temperature or salinity, or change depth: increased
+ pressure compresses any flexible air pockets, including the BCD
+ itself, neoprene foam, or a dry-suit.
+ Most BCDs have their own pressure hoses coming from the first stage
+ regulator that supply air.
+ Sometimes there is only one vent valve, which has to be at the
+ highest orientation or air will not vent out of the bladders.
+:Tank: Most tanks are made of steel or aluminum and can store compressed
+ air of up to 3000psi. They are stored at pressure to prevent moisture
+ from leaking in. There is a valve built into the tank itself that
+ usually gets taken apart and repaired every two years. Tanks
+ can last for decades even with heavy use; they are pressure tested
+ for fatigue and leaks.
+:Regulator: The first-stage regulator is connected to the tank and steps
+ the pressure down to about 250psi above the surrounding/ambient
+ pressure. Hoses carry air at this mid-level pressure to the second
+ stage regulator/mouthpiece, which steps the pressure down to
+ about what is in your lungs. Depending on the regulator they can
+ be stiff (you have to suck a bit to get air, but then it rushes
+ in with force) or very natural feeling (air comes very smoothly
+ on inhalation and doesn't press into your lungs).
+:Alternate: These days almost everybody carries a second regulator mouthpiece
+ for emergencies. These are always on and ready to breath from,
+ but usually stiffer so they don't free-flow as often.
+:Dive Computer:
+ A dive computer monitors time and depth to give you an accurate picture
+ of how much excess nitrogen is in a diver's bloodstream. By
+ continuously integrating they usually "give more time at depth" than
+ hand calculations using tables (which err towards safety).
+:Dry Suit: A dry suit is a sealed and air tight, keeping the diver's skin dry.
+ Extra insulation is needed to give warmth underneath. Some dry
+ suits are made of compressed neoprene.
+ A dry suit has to be constantly adjusted with tank air just like
+ the BCD to maintain inflation and buoyancy.
+:Wet Suit: Wet suits work on the principle of holding water against the skin:
+ a diver's body warms this water and stays cozy as long as water
+ flow is restricted enough. Even little bit too much flow through
+ wrist or ankle openings can be very cold.
+
+
+Depths
+------
+A PADI Open Water Diving course gives a recommended limit of 20m/60ft.
+A "deep dive adventure course" gives a recommended limit of 30m/100ft,
+and additional experience gives a limit of 40m/130ft.
+
+With careful decompression stops and enriched compressed air (higher oxygen
+content) it's possible to reach depths of hundreds of meters. Sometimes
+commercial divers will dive for many hours using surface supplied air,
+then live at the surface in a compression chamber overnight between dives
+to stay at the same pressure [*]_.
+
+History
+-------
+I'm pretty sure `Jacques Cousteau`_ invented the aqualung, which is the basis
+for modern diving, but I'll have to check.
+
+.. _Jacques Cousteau: /k/jacquescousteau/
+
+Flying
+------
+After a regular no-decompression dive, wait at least 12
+hours before flying (or going to high altitude, eg over 300m).
+
+.. [*] Need a citation, heard this word of mouth
diff --git a/tmp/Saccade b/tmp/Saccade new file mode 100644 index 0000000..85693c6 --- /dev/null +++ b/tmp/Saccade @@ -0,0 +1,7 @@ +Saccade +------- + +Saccades are small movements of the eye which generate a delta in our stream +of vision. Similar to the phenomena of "only seeing movement". + +(based on Jeff Hawkin's book "On Intelligence") diff --git a/tmp/Teaching CS b/tmp/Teaching CS new file mode 100644 index 0000000..2c21cc4 --- /dev/null +++ b/tmp/Teaching CS @@ -0,0 +1,97 @@ +==================================== +Notes on Teaching Computer Science +==================================== + +:author: Bryan Newbold <bnewbold@mit.edu> + +.. note:: Incomplete, just a structure of starting topics + +.. contents:: + +In thinking about how to teach somebody new "how to program" or "about +computers", it seems like getting the rough big picture is the best first step. + + +Engineering and Scientific Philosophies +----------------------------------------- +keywords: computation, computability, hierarchy, interface, implementation + +In approaching computer science it is important to note an arbitrary division +of the field between "computation" and "computability" that has arisen over +the years. Similar to the "theory" vs "experiment" schisms in other scientific +fields like physics, "computation" puts emphasis on actually generating +hardware and software to run in the real world, while "computability" focuses +on what can be computed and generalizations of specific computations. Of course +they are two sides of the same coin and should be appreciated together. + +It is almost impossible to deal with computer systems (hardware or software) +without breaking them up into modules and layers. Perhaps more so than in any +other field, conceptual barriers are reflected in the actual design and +implementation of systems, which can make it hard to learn how things work +because their inner workings are shielded from view both literally and +figuratively. For example, a software developer writing a web browser doesn't +have to know about what kind of monitor the user is sitting in front of, +what kind of physical link to the internet they have (or even how this +connection is managed), the details of their computer architecture, how their +application is delegated computing resources, what kind of mouse is being used, +etc etc. + +A more formal example is the ethernet protocol, which is used to +pass data between nodes in a relatively unstructured network. The ethernet +protocol itself lies above the physical "link layer", which means the same +protocol can be used for wireless radio communications or with conducting +wires. It lies below any sort of higher network layers and far below the +"application layer", so large amounts of data can be streamed over it between +two nodes, or messages between dozens of nodes can be passed over it, or it +can be only one link in a very large web of interconnections. This flexibility +has made it ubiquitous and is the protocol most network devices use without +a hitch, but occasionally it's imperfections can lead to problems at higher +levels which are hard to track down. + +Turing Completeness +----------------------------------------- +keywords: finite state machine, deterministic + +Personal Computer Hierarchy +----------------------------------------- +keywords: CPU, RAM, hard disk, peripherals, network, BIOS, motherboard, + operating system, serial, parallel, interrupts, multicore, register + +UNIX Operating Systems +----------------------------------------- +keywords: file system, kernel, driver, threading, + +UNIX is the Latin of operating systems: there were operating systems that came +after, and the average user isn't running a UNIX operating system, but it's +design is simple, functional, and has represents the dominant paradigms for +modern (non-experimental or special use) operating systems. + +As some context, Microsoft Windows is not directly based on UNIX. Apple OSX +and subsequent versions is built on top of a UNIX core. Linux is an open source +implementation of UNIX. BSD was the free UC Berkeley distribution of UNIX which +has branched off into open source implementations like FreeBSD, OpenBSD, and +NetBSD. "UNIX" got started as a Bell Labs research project in the 70's (?) + + +The Internet +----------------------------------------- +keywords: IP (internet protocol), ARP, MAC, routing, servers, backbone, + protocol, email, http, html + + +Software Development Tools +----------------------------------------- +keywords: compiler, lexical analysis, library, language, interpreter + + +Data Formats, Structures, and Algorithms +----------------------------------------- +keywords: string, integer, bit, list, pointer, tree, sort, P/NP + + +Design Paradigms +----------------------------------------- +keywords: server/client, object oriented, wrappers, KISS, parallelization, + resource locking, serialization, buffer + + diff --git a/tmp/Topics of Curiosity b/tmp/Topics of Curiosity new file mode 100644 index 0000000..6ef2976 --- /dev/null +++ b/tmp/Topics of Curiosity @@ -0,0 +1,50 @@ +--------------------- +Topics of Curiosity +--------------------- + +*or, list of future knowledge items* + +* United Nations +* List of International Treaties + + including signatories + +* Ethernet +* Benthic Biology +* Antarctica +* Kyoto Protocol +* Sensory Deprivation +* Beat Authors +* Harvey Mudd +* National Science Foundation + + And other US national science organizations + +* Iraq War + + Strategy, costs, political figures, history, technology, prospects, companies, etc. + +* Recycling +* Pollution sources in the United States +* US Education System +* US Judicial Branch +* Kennedy School of Government +* Democratic Party +* Republican Party +* Green Party +* Bob Dole +* Al Gore +* Obama +* Book Publishing +* Internet + + Power consumption, user numbers, global connectivity, core and backbone services + +* One Laptop Per Child + + Bundled knowledge, regions, implementation plans, new software concepts, connectivity + +* Paul Dirac +* LaTeX +* vim +* pykrete |