This is a pleading for Descriptive Geometry. From the very first, Descriptive Geometry is a method to study 3D geometry through 2D images thus offering insight into structure and metrical properties of spatial objects, processes and principles. The education in Descriptive Geometry provides a training of the students’ intellectual capability of space perception. Drawings are the guide to geomet...

Let C be a class of graphs and π be a graph parameter. Let Φ be a formula in the first-order language containing only the adjacency and the equality relations. We say that Φ defines C on connected graphs with sufficiently large π if there is a constant k such that, for every connected graph G with π(G) ≥ k, Φ is true on G exactly when G belongs to C. For a fixed connected graph F , let S(F ) de...

We show in this paper a special extended logic, partition logic based on so called partition quantifiers, is able to capture some important complexity classes NP, P and NL by its natural fragments. The Fagin’s Theorem and Immerman-Vardi’s Theorem are rephrased and strengthened into a uniform partition logic setting. Also the dual operators for the partition quantifiers are introduced to expose ...

We propose power-aware on-line task scheduling algorithms for mixed task sets which consist of both periodic and aperiodic tasks. The proposed algorithms utilize the execution behaviors of scheduling servers for aperiodic tasks. Since there is a trade-off between the energy consumption and the response time of aperiodic tasks, the proposed algorithms focus on bounding the response time degradat...