linux administration a beginners guide 6 e

... released is free, and that no one can ever take away these freedoms It is acceptable to take the software and resell it, even for a profit; however, in this resale, the seller must release the ... All trademarks are trademarks of their respective owners Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the ... More formally, such packages are called distributions You may have heard of the Linux distributions named Red Hat, SuSE, Mandrake, and Caldera, which have received a great deal of press and have...

Ngày tải lên: 24/04/2014, 09:18

... 32­in aluminum bar (see Fig 8. 26) The aluminum bar is marked at the center Each bend required in the bumper is also marked in pencil The material is placed in a vise at each pencil mark and bent to the angle required ... holes are drilled in the robot base behind the servomotor The holes should be placed so that the bumper (once secured to the base) has adequate clearance (1�8 to 1�4 in) from the back wheels The matching center hole on the base must be off­ ... light  sensitive) Walter later renamed the style of robots Machina Speculatrix after observing the complex behavior they exhibited In the early 1940s transistors had not been invented, so the electronic neu­...

Ngày tải lên: 10/08/2014, 04:22

... the content flow The browser software brings the separate pieces together into the final page Videos and other embedded media files are added in much the same way The assembly of the page generally ... (like reading this book), taking advantage of available templates, and perhaps even investing in a visual web design tool such as Adobe Dreamweaver may be all you need to accomplish the task at ... documents, style sheets, scripts, and images that make up a site At web design firms, the team that handles the creation of the files that make up the website (or templates for pages that get assembled...

Ngày tải lên: 24/01/2014, 17:16

... system One type of database, and the type discussed here, is a relational database A relational database is a collection of tables with relationships A database is designed to describe a situation ... knowledge of the database concept, database software, and the knowledge of potential errors and their effect As more and more data is collected the task of data management becomes more intensive ... The other two options, Cascade Update Related Fields and Cascade Delete Related Records, are optional Cascade Update Related Fields will automatically update the foreign key in the child table...

Ngày tải lên: 16/03/2014, 16:20

... both easy and inexpensive That makes it a lucrative market for independent developers wishing to take advantage of the iTunes Store’s large user base Independent developers can develop applications ... to Java As most universities teach Java these days, and Java seems to be the most prevalent language for systems developers, in this book we assume some very basic Java programming experience TIP ... management can be a pain, it is not a huge limitation Just be aware that forgetting to release an object is all too easy a mistake to make As you will see in Chapter 5, there are tools to help...

Ngày tải lên: 19/03/2014, 11:52

Ngày tải lên: 31/03/2014, 16:27

... Flash interface and a small amount of scripting experience is assumed We believe we’ve explained the material herein clearly and concisely enough for any reader to get started, so even if you are ... set a variable to and then set that same variable to in the following line, the value would be reassigned, and the value of the variable would be However, there are times when you need one variable ... anywhere—be that in the root timeline, another movie clip, or nested even deeper—because the various stages aren’t named Table 2-2 and Table 2-3 draw parallels to the operating system and web site...

Ngày tải lên: 31/03/2014, 16:56

... averages are what the name implies: mathematical averages of recent price action that are recalculated for each period The result is a dynamic value that moves over time Chartists use moving averages ... prices themselves are above the average then the market is considered to be bullish, again, in that specific time frame A typical way to use averages is to buy when prices move above the average ... paper And what about those projected earnings? Again, as mentioned earlier, they are really only educated guessed about the future business success used to make educated guesses about price action...

Ngày tải lên: 03/05/2014, 12:54

... Database File Database File Database File Database File Physical Layer Database File Physical Data Independence Database layers of abstraction The Physical Layer The physical layer contains the ... data bank and a database? A: A data bank and a database are the same thing Data bank is merely an older term that was used by the scientists who developed early database systems In fact, the term ... (ASE) define a database as a collection of data items that have a common owner, and multiple databases are typically managed by a single instance of the database management software This can all...

Ngày tải lên: 05/05/2014, 13:27

... easier access, many people change their home page to a search engine or a news site customized according to their needs These personalized sites are often called portals and also offer free e- mail ... can even print or save these pages to review at a later time or to keep in a reference library Because the Web is open source, meaning your code is free for anyone to see, copying other developers’ ... code needed to render a page properly, and so they end up repeating code many more times than necessary This leads to large file sizes and longer downloads ● Speedier editing The large-scale WYSIWYG...

Ngày tải lên: 05/05/2014, 14:14

... All trademarks are trademarks of their respective owners. Rather than put a trade­ mark symbol after every occurrence of a trademarked name, we use names in an edi­ torial  fashion  only,  and  to  the  benefit  ... carrier  board  (hardware).  The  EPIC  software package has two executable files, one for DOS and another version of the soft­ ware for Windows It is the EPIC hardware and software that takes the compiled .hex ... CodeDesigner  integrates these  software  and  hardware  packages  so  that  they  can  operate  within  its Windows environment CodeDesigner has many useful features that help you write code and that...

Ngày tải lên: 22/05/2014, 18:13

... All trademarks are trademarks of their respective owners. Rather than put a trade­ mark symbol after every occurrence of a trademarked name, we use names in an edi­ torial  fashion  only,  and  to  the  benefit  ... carrier  board  (hardware).  The  EPIC  software package has two executable files, one for DOS and another version of the soft­ ware for Windows It is the EPIC hardware and software that takes the compiled .hex ... term  firmware This  word  is  used  when  software  is embedded in a hardware device that can read and execute by the device but cannot be modified. So when our program (software) is embedded (uploaded)...

Ngày tải lên: 10/08/2014, 04:22

... automatically opens a DOS window and starts the executable program on the EPIC diskette The executable program creates a new subdirectory on the com­ puter’s hard drive called EPIC It decompresses and copies all the necessary ... drive, remove  the diskette and store it in a safe place, in case it is needed in the future Supplemental—Applications Directory It would be a good idea at this time if we created another subdirectory where ... Programming the compiled code into a PIC microcon­ troller  requires  the  EPIC  software  and  hardware CodeDesigner  integrates these  software  and  hardware  packages  so  that  they  can  operate ...

Ngày tải lên: 10/08/2014, 04:22

... 5.7 we can see the two additional files that the compiler created One file is the wink.asm file and is the assembler source code  file  that  automatically  initiated  the  macroassembler  to  ... compile  the assembly code to machine language hexadecimal code The hex code file is the second file created, called wink.hex Programming the PIC Chip To  program  the  PIC  chip, we  must  connect  ... the  EPIC  programming  carrier board (see Fig 5.8), to the computer The EPIC board connects to the printer port The printer port is also called the parallel port Either name may be used; they ...

Ngày tải lên: 10/08/2014, 04:22

... not  dabbled  in  electronics  very  much, I  want  to describe the solderless breadboard (see Fig 6. 1) in detail As the name implies, you  can  breadboard  (assemble  and  connect)  electronic  ... Chapter Five Figure 5.14 Hexadecimal numbers showing in EPIC window are the machine language version of the wink.bas program that is uploaded (programmed) into the 16F84 microcontroller I have noticed that when I place a brand new PICmicro 16F84 chip into the ... The  holes  on  the  board  are  plugs When  a wire  or  pin  is inserted into the hole, it makes intimate contact with the metal connector strip inside The holes are properly distanced so that integrated circuits and many...

Ngày tải lên: 10/08/2014, 04:22

... The next number, separated by a comma, is the value we want to write in that memory address In this case it’s the number 1 For the PicBasic Pro compiler, the TRISB and TRISA registers are already ... Depending upon which PicBasic compiler is used, the commands are a little different For the PicBasic compiler, the command to write to a register is the poke command The program line to write the decimal value 1 into the TRISB register will look like this: ... RB2 has a bit weight of 4, and RB6 has a bit weight of 64 We add these num­ bers (4 � 64  � 68 ) and write that number into the port B register When we write the number 68  into the port B register, the LEDs connected...

Ngày tải lên: 10/08/2014, 04:22

... idea to buy a few more than you need and measure the resistances, to find a pair whose resistances are close There are a few ways you can measure the resistance The simplest method to use a volt­ohmmeter, set to ohms Keep the light intensity the same as you measure the resistance ... for this robot that matches, as best as one can match them, in resistance Since  the  resistance  value  of  the  CdS  cells  can  vary  so  greatly, it’s  a good idea to buy a few more than you need and measure the resistances, ... their respective resistances are approximately the same As long as each sensor is within ±10 points of the other, the PIC program will see them as equal and won’t move the servomotor (steering) When the sensor array is not proper­...

Ngày tải lên: 10/08/2014, 04:22

... pair whose resistances are close There are a few ways you can measure the resistance The simplest method to use a volt­ohmmeter, set to ohms Keep the light intensity the same as you measure the resistance Choose two CdS cells ... as best as one can match them, in resistance Since the resistance values of the CdS cells can vary so greatly, it’s a good idea to buy a few more than you need and measure the resistances to find a pair whose resistances are close ... and some­ times  humans Biped  walkers  are  still  a little  rare, requiring  balance  and  a good deal more engineering science than multilegged robots A bipedal robot walker is discussed in detail in Chap...

Ngày tải lên: 10/08/2014, 04:22

... in shorter than the front and back legs After the holes are drilled, we need to bend the aluminum bar into shape Secure the aluminum bar in a vise 23/4 in from the end with the drilled holes Pressure is applied to bend the aluminum bar at a 90° ... increasing  the  efficiency  and  effectiveness At  the  most  basic  level, speech commands allow the user to perform parallel tasks (i .e. , hands and eyes are  busy  elsewhere)  while  continuing  ... Repeat the twist on the other side After the two 90° twists have been made, make the other 90° bend for the legs, as we have done before for the front and back legs Mounting the servomotors The back servomotors are attached to the aluminum body using plastic 6 32...

Ngày tải lên: 10/08/2014, 04:22