This paper proposes a Satisfiability Modulo Theory based formulation for floorplanning in VLSI circuits. The proposed approach allows a number of fixed blocks to be placed within a layout region without overlapping and at the same time minimizing the area of the layout region. The proposed approach is extended to allow a number of fixed blocks with ability to rotate and flexible blocks (with variable width and height) to be placed within a layout without overlap. Our target in all cases is reduction in area occupied on a chip which is of vital importance in obtaining a good circuit design. Satisfiability Modulo Theory combines the problem of Boolean satisfiability with domains such as convex optimization. Satisfiability Modulo Theory provides a richer modeling language than is possible with pure Boolean SAT formulas. We have conducted our experiments on MCNC and GSRC benchmark circuits to calculate the total area occupied, amount of deadspace and the total CPU time consumed while placing the blocks without overlapping. The results obtained shows clearly that the amount of dead space or wasted space is reduced if rotation is applied to the blocks.

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The size of the WWW is increasing rapidly and its nature is dynamic, building an efficient search mechanism is very necessary. A vast number of pages continually being added every day, so fetching information about a special-topic is gaining importance, which poses exceptional scaling challenges for general-purpose crawlers and search engines. This paper describes a web crawling approach based on best first search. Instead of collecting and indexing all available web documents to be able to answer all possible queries, a focused crawler choose the links that are likely to be most relevant for the crawl, and avoids irrelevant links of the document. This leads to significant savings in hardware as well as network resources and also helps keep the crawl more up-to-date. To accomplish such goal-directed crawling, select top most K relevant documents for a given query and then expand the most promising link chosen according to link score, to circumvent irrelevant regions of the web. General TermsWeb Crawler, search engine, hyperlink.