We introduce the tree cross-product problem, which abstracts a data structure common to applications in graph visualization, string matching, and software analysis. We design solutions with a variety of tradeoffs, yielding improvements and new results for these applications.

purpose: the present research aimed to study internet and electronic recourses searching behavior of geography ph.d. students of tehran university. methodology: using a questionnaire survey, demographic features and educational trends of 61 studied students were analyzed. findings: results showed that all of the statistical population used e-mail services, databases and search engines. most of ...

Introduction .............................................................................................................. 179 Signaling Methods ................................................................................................................................. 180 Signal Complexity and Patterns .........................................................................................

All behavior is proximally caused by the brain, but the neural causes of most complex behaviors are still not understood. Much of our ignorance stems from the fact that complex behavior depends on distributed neural control. Unlike a reflex, where the arc from sensation to action can be traced through a few synapses, most volitional behavior involves a dense causal web through which stimuli, me...

Any algorithm for finding a pattern of length k in a string of length n must examine at least n k + of the characters of the string in the worst case. By considering the pattern 00 0, we prove that this is the best possible result. Therefore there do not exist pattern matching algorithms whose worst-case behavior is "sublinear" in n (that is, linear with constant less than one), in contrast wit...

The study investigated how users’ emotion control and search tasks interact and influencethe Web search behavior and performance among experienced Web users. Sixty-sevenundergraduate students with substantial Web experience participated in the study. Effectsof emotion control and tasks were found significant on the search behavior but not on thesearch performance. The intera...

What fascinates us about animal behavior is its richness and complexity, but understanding behavior and its neural basis requires a simpler description. Traditionally, simplification has been imposed by training animals to engage in a limited set of behaviors, by hand scoring behaviors into discrete classes, or by limiting the sensory experience of the organism. An alternative is to ask whether...

Coordination of animal behavior with reproductive status is often achieved through elaboration of hormones by the gonad. In the nematode Caenorhabditis elegans, adult males explore their environment to locate mates. Mate searching is regulated by presence of mates, nutritional status, and a signal from the gonad. Here we show that the gonadal signal acts via the nuclear receptor DAF-12, a prote...