Harvard architecture

Harvard architecture
The Harvard architecture is a computer architecture with physically separate storage and signal pathways for instructions and data.
The term originated from the Harvard Mark I relay-based computer, which stored instructions on punched tape (24 bits wide) and data in electro-mechanical counters. These early machines had data storage entirely contained within the central processing unit, and provided no access to the instruction storage as data.
Programs needed to be loaded by an operator; the processor could not boot itself.
Today, most processors implement such separate signal pathways for performance reasons but actually implement a modified Harvard architecture, so they can support tasks such as loading a program from disk storage as data and then executing it.
http://en.wikipedia.org/wiki/Harvard_architecture

CISC

CISC
A complex instruction set computer CISC
A complex instruction set computer (CISC) is a computer where single instructions can execute several low-level operations (such as a load from memory, an arithmetic operation, and a memory store) and/or are capable of multi-step operations or addressing modes within single instructions.
The term was retroactively coined in contrast to reduced instruction set computer (RISC)

Examples of CISC instruction set architectures are System/360 through z/Architecture, PDP-11, VAX, Motorola 68k, and x86.
http://en.wikipedia.org/wiki/Complex_instruction_set_computing

RISC

RISC
Reduced instruction set computing, or RISC  is a CPU design strategy based on the insight that simplified (as opposed to complex) instructions can provide higher performance if this simplicity enables much faster execution of each instruction.
A computer based on this strategy is a reduced instruction set computer, also called RISC.
The opposing architecture is known as complex instruction set computing, i.e. CISC.

Well known RISC families include DEC Alpha, AMD 29k, ARC, ARM, Atmel AVR, Blackfin, Intel i860 and i960, MIPS, Motorola 88000, PA-RISC, Power (including PowerPC), SuperH, and SPARC
http://en.wikipedia.org/wiki/Reduced_instruction_set_computing

Fuzzy logic

Fuzzy logic
Fuzzy logic iss a form of many-valued logic or probabilistic logic; it deals with reasoning that is approximate rather than fixed and exact.
Compared to traditional binary sets (where variables may take on true or false values) fuzzy logic variables may have a truth value that ranges in degree between 0 and 1.
Fuzzy logic has been extended to handle the concept of partial truth, where the truth value may range between completely true and completely false
http://en.wikipedia.org/wiki/Fuzzy_logic

• Fuzzy Logic (FL) is a method of reasoning that resembles human reasoning. The approach of FL imitates the way of decision making in humans that involves all intermediate possibilities between digital values YES and NO.

The conventional logic block that a computer can understand takes precise input and produces a definite output as TRUE or FALSE, which is equivalent to human’s YES or NO.
http://www.tutorialspoint.com/artificial_intelligence/artificial_intelligence_fuzzy_logic_systems.htm

• In this work, we focus   the   detection   and   prediction   mechanism   against DDoS  attacks  in  IEEE  802.15.4  using  Fuzzy  logic  system. The   main   contribution   of   Fuzzy   based   detection   and prediction system (FBDPS) is to detect the DDoS attackers

by comparing the energy consumption of sensor nodes.
http://ijcsi.org/papers/IJCSI-10-6-1-293-301.pdf

infix prefix postfix notations

Infix notation

Infix notation is the common arithmetic and logical formula notation, in which operators are written infix-style between the operands they act on (e.g. 2 + 2)
It is not as simple to parse by computers as prefix notation ( e.g. + 2 2 ) or postfix notation ( e.g. 2 2 + ), but many programming languages use it due to its familiarity

In infix notation, unlike in prefix or postfix notations, parentheses surrounding groups of operands and operators are necessary to indicate the intended order in which operations are to be performed. In the absence of parentheses, certain precedence rules determine the order of operations.

http://en.wikipedia.org/wiki/Infix_notation


Prefix notation
Polish notation, also known as Polish prefix notation or simply prefix notation, is a form of notation for logic, arithmetic, and algebra. Its distinguishing feature is that it places operators to the left of their operands.

http://en.wikipedia.org/wiki/Polish_notation


Postfix notation
Reverse Polish notation (RPN) is a mathematical notation in which every operator follows all of its operands, in contrast to Polish notation, which puts the operator in the prefix position.

http://en.wikipedia.org/wiki/Reverse_Polish_notation

What's the difference between throw, throwable & throws?

throw and throws are java keywords and Throwable is a super class for errors and exceptions.
Only the objects of the Throwable can be thrown by the “throws” or “throw” statement.

throws :
used on the method to specify than an exception(s) can be thrown. The throws clause tells the complier that this particular exception would be handled by the calling method.

throw :
it is a statement to throw the exception when certain condition is failed or other logic had returned exception. This can be used in any part of code where you feel a specific exception needs to be thrown to the calling method

http://www.linkedin.com/groups/Whats-difference-between-throw-throwable-70526.S.200485518?view=&srchtype=discussedNews&gid=70526&item=200485518&type=member&trk=eml-anet_dig-b_pd-ttl-cn&ut=17ZTwoVDpUpBA1