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This paper studies the idea of answering range searching queries using simple data structures. The only data structure we need is the Delaunay Triangulation of the input points. The idea is to first locate a vertex of the (arbitrary) query polygon $\{\backslash cal\; q\}$ and walk along the boundary of the polygon in the Delaunay Triangulation and report all the points enclosed by the query polygon. For a set of uniformly distributed random points in 2-D and a query polygon the expected query time of this algorithm is $O(n^\{1/3\}\; +\; Q\; +\; \{\backslash bf\; E\}K\; +\; L\_\{r\}n^\{1/2\})$, where Q is the size of the query polygon $\{\backslash cal\; q\}$, $\{\backslash bf\; E\}K\; =\; O(n\backslash bcdot\; area(\{\backslash cal\; q\}))$ is the expected number of output points, $L\_\{r\}$ is a parameter related to the shape of the query polygon $\{\backslash cal\; q\}$ and n, and $L\_\{r\}$ is always bounded by the sum of the edge lengths of $\{\backslash cal\; q\}$. Theoretically, when $L\_\{r\}\; =\; O(1/n^\{1/6\})$ the expected query time is $O(n^\{1/3\}\; +\; Q\; +\; \{\backslash bf\; E\}K)$, which improves the best known average query time for general range searching. Besides the theoretical meaning, the good property of this algorithm is that once the Delaunay Triangulation is given, no additional preprocessing is needed. In order to obtain empirical results, we design a new algorithm for generating random simple polygons within a given domain. Our empirical results show that the constant coefficient of the algorithm is small, at least for the special (practical) cases when the query polygon is either a triangle (simplex range searching) or an axis-parallel box (orthogonal range searching) and for the general case when the query polygons are generated by our new polygon-generating algorithms and their sizes are relatively small. [ABSTRACT FROM AUTHOR]

Copyright of Psicologia: Reflexão e Critica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Psicologia: Reflexão e Critica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Psicologia: Reflexão e Critica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At first sight one might be tempted to regard Descartes' »cogito ergo sum« as logically true by existential generalisation. This however would neither exhaust the specific epistemic content of »cogito« nor reveal the philosophical peculiarities of »sum« which the author takes to have two ontologically different meanings. The full sense of »cogito ergo sum« finally turns out to be 'Credo me cogitare ergo scio me esse'. Furthermore this proposition can formally be proved to be true by means of epistemic logic. [ABSTRACT FROM AUTHOR]

In preparation for the treatment of Chrysobalanaceae for Flora Malesiana, New and critical taxa are discussed and described. Two new species were found, Atuna cordata and Parastemon grandifructus. Hunga fusicarpa is transferred to the genus Licania as L. fusicarpa. Species complexes around Parinari costata and P. papuana are discussed; in both cases previously recognized species are reduced to subspecific rank within rather polymorphic species. [ABSTRACT FROM AUTHOR]