Popular word on line is a kind of language form which is welcomed by netizens.The popular word on line is the most active part of network language.They are made of expressions what the internet users are established b...Popular word on line is a kind of language form which is welcomed by netizens.The popular word on line is the most active part of network language.They are made of expressions what the internet users are established by usage.The popular words on line have a very strong nature of medium.They are the comprehensive products which come from the facts of social politics,economics,culture,environment and people's psychological activities etc.of a certain time.The total amount of new emerging popular words on line is not so many every year,but the influence of them can not be belittled.This study focuses on the popular words on line with the cases of the popular words occured in recent years.It works on the reasons for their rapid spreading.The author summarizes their characteristics and put forward some ways for the guidance of the popular words on line.展开更多
A graph G=(V,E) is representable if there exists a word W over the alphabet V such that letters x and y alternate in W if and only if (x ,y) is in E for each x not equal to y . The motivation to study representable gr...A graph G=(V,E) is representable if there exists a word W over the alphabet V such that letters x and y alternate in W if and only if (x ,y) is in E for each x not equal to y . The motivation to study representable graphs came from algebra, but this subject is interesting from graph theoretical, computer science, and combinatorics on words points of view. In this paper, we prove that for n greater than 3, the line graph of an n-wheel is non-representable. This not only provides a new construction of non-repre- sentable graphs, but also answers an open question on representability of the line graph of the 5-wheel, the minimal non-representable graph. Moreover, we show that for n greater than 4, the line graph of the complete graph is also non-representable. We then use these facts to prove that given a graph G which is not a cycle, a path or a claw graph, the graph obtained by taking the line graph of G k-times is guaranteed to be non-representable for k greater than 3.展开更多
文摘Popular word on line is a kind of language form which is welcomed by netizens.The popular word on line is the most active part of network language.They are made of expressions what the internet users are established by usage.The popular words on line have a very strong nature of medium.They are the comprehensive products which come from the facts of social politics,economics,culture,environment and people's psychological activities etc.of a certain time.The total amount of new emerging popular words on line is not so many every year,but the influence of them can not be belittled.This study focuses on the popular words on line with the cases of the popular words occured in recent years.It works on the reasons for their rapid spreading.The author summarizes their characteristics and put forward some ways for the guidance of the popular words on line.
文摘A graph G=(V,E) is representable if there exists a word W over the alphabet V such that letters x and y alternate in W if and only if (x ,y) is in E for each x not equal to y . The motivation to study representable graphs came from algebra, but this subject is interesting from graph theoretical, computer science, and combinatorics on words points of view. In this paper, we prove that for n greater than 3, the line graph of an n-wheel is non-representable. This not only provides a new construction of non-repre- sentable graphs, but also answers an open question on representability of the line graph of the 5-wheel, the minimal non-representable graph. Moreover, we show that for n greater than 4, the line graph of the complete graph is also non-representable. We then use these facts to prove that given a graph G which is not a cycle, a path or a claw graph, the graph obtained by taking the line graph of G k-times is guaranteed to be non-representable for k greater than 3.