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Notes on Sequential Pattern Mining (2) -- Partial Order Pattern Mining and Contrast Mining

1. In , the authors induce TEIRESIAS algorithms to mining combinatorial patterns with gap constraints in biological sequences. The patterns TEIRESIAS mined is similiar with the common sequential patterns, but it could contain "." the wild card which is also in the alphbel of the sequences database standing for any other item available, for example pattern "A..B" is a length-4 pattern, with two arbitrary items between the first A and the last B. Patterns "AC.B", "AADB" are all said to be more specific than pattern "A..B". TEIRESIAS mining all the maximal patterns () with a support over a min threshold K. There some key points of TEIRESIAS algorithms: 1)The growth of the patterns The growth of the patterns is accomplished by convolute current pattern by a short length pattern. Pattern A and pattern B are convolutable if the last L(very small) characters of pattern A is the same as the first L characters of pattern B, then

ns-2 2.30 on Fedora Core 6(FC6)

The allinone package of the network simulator ns-2 2.30 whish is newly release on sep 24, 2006 could be installed on Fedora Core 6 easily, and work very well on it. There are a lot of problem about the installation of ns-2 on ubuntu and previous fedora core editions.

Notes on algorithms(2) -- Principles of Dynamic Programming

Dynamic Programming is to convert a problem into a polynomial time algorithm by storing some of the middle results first. This is to avoid searching some redundant spaces in the problem. In the book (J.K. and E.T.), the following 3 are the rules of dynamic programming: 1) There are only a polynomial number of subproblems. 2) The solution to the original problem can be easily computed from the solutions to the subproblems. 3) There is a natural ordering on subproblems from "seallest" to "largest".

Notes on algorithms(1) -- Finding Patterns in a File -- An example on Parallelized Programming

Notes on (Gregory R. Andrews). The problem is to find a string pattern in a file, and print lines containing the patterns. The Sequential program of the problem is as below: string line; read a line of input from stdin into line; while(!EOF){ look for pattern in line; if (pattern is in line) write line; read next line of input; } The point we can parallelize is inside the while loop, the pattern-finding step and the line-reading step. But here we use the same variable line, and we must eliminate it. So here we induces a variable line2 to perform the reading operation, and variable line1 to perform the finding operation, another variable buffer is to communicate between line1 and line2. The program is as below: string buffer; bool done = false; co #process 1 string line1; while (true){ wait for buffer to be full or done to be true; if (done) break; line1 = buffer; signal that buffer is empty; look for pattern in line1; if (pattern is in line1) write line1; } //#process 2 string line2; w

Notes on Knowledge Representation

1.Intruduction The paper (John Molopoulos,1981) is a brief overview of terminology and related issues on knowledge representation. Knowledge Representation is a central problem in Artificial Intelligence (AI) today. Its importance stems from the fact that the current design paradigm for "intelligent" systems stresses the need for expert knowledge in the system along with associated knowledge-handling facilities. The basic problem of KR is the development of a sufficiently precise notation for representing knowledge. We shall refer to any such notation as a (knowledge) representation scheme. Using such a scheme one can specify a knowledge base consisting of facts. 2.A Taxonomy of Representation Schemes Representation schemes have been classified into declarative and procedural ones . The paper subdivide declarative schemes into logical and (semantic) network ones. 2.1 Logical Representation schemes is such schemes employ the notions of constant, variable, function, predicate,

Notes on Sequential Pattern Mining (1)

1. Here I write about some definitions about Sequential Pattern Mining. We define the basic elements items, and S the set of all items. The subset of S, defined as event, inside a event, the items are unordered. The ordered set of event is defined as Sequence. We define size of a Sequence the number of events, and length of a Sequence the total count of the instances of items. The sequence of length l is called l-sequence. 2. Sequences is the basic logical elements of Sequential Pattern Mining. While implementing some mining algorithm, we need a high efficiency impletation of Sequence. So to design the class is a very important and fundamental work. We need to design the Sequence class to meet the following requirments: 1) We could visit the a sequence by items and by event, and for a single item, we could locate it in the form "event X item Y" or in the form "item T from beginning of the sequence"; 2) We need to get a sub-sequence of sequence easily and need to sav

Notes on Patterns(1)

1.Patterns are of contexts, problems and solutions, their relationship is as below: Pattern:(1)Context : design situation giving rise to a design problem(2)Problem : set of forces arising in the context(3)Solutions : Configure to balance the forces. It's of [1] Sturctures with components and relationships; [2] Run-time behaviour The phiolosophy of Patterns is to find some stable point among the balances of software development, I think. 2.Layer Architectural Patterns one : Layer.The Layer Pattern helps to structure applications that can be decomposed into groups of subtasks in which each group of subtasks is at a particular level of abstractioin. It's architecture of software, such as OSI, TCP/IP layer structure. To design Layer Pattern, we should consider about something as below:1) The interfaces between layers;2) The abstraction of each isolated layers 3.Broker The Broker pattern is of 6 parts:Server, Client, Broker, Server-Side Proxy, Client-Side Proxy, and Bridge. The main

Some Epigrams on Computer Sciences

“Error, keyboard not found - press F1 to continue.” - BIOS system message “Distributed file systems are a cruel hoax.” - Zalman Stern “A computer lets you make more mistakes faster than any other invention in human history, with the possible exception of handguns and tequila.” - Mitch Ratcliffe “Large increases in cost with questionable increases in performance can be tolerated only in race horses and women.” - Lord Kelvin “Memory is like an orgasm. It’s a lot better if you don’t have to fake it.” - Seymore Cray (on virtual memory) “Software Engineering is that part of Computer Science which is too difficult for the Computer Scientist.” - F. L. Bauer “If you torture the data enough, it will confess” - Ronald Coase “If you give someone a program, you will frustrate them for a day; if you teach them how to program, you will frustrate them for a lifetime.” “Programming is like sex: one mistake and you have to support it for the rest of your life.” - Michael Sinz “Einstein argued that ther