NP-Hard Module Rotation Problems
نویسندگان
چکیده
Preplaced circuit modules may be rotated to improve performance and/or routability. We show that several simple versions of the module rotation problem are NP-hard.
منابع مشابه
Parallelizing Assignment Problem with DNA Strands
Background:Many problems of combinatorial optimization, which are solvable only in exponential time, are known to be Non-Deterministic Polynomial hard (NP-hard). With the advent of parallel machines, new opportunities have been emerged to develop the effective solutions for NP-hard problems. However, solving these problems in polynomial time needs massive parallel machines and ...
متن کاملResearch on None Uniform Rational B-spline Surface and Agent for Numerically Controlled Layout Design
Research on the integrated NC conceptual layout design (I-NCC) concerned with a broader area of interests. The key issues of I-NCC system are associated with NURBS and agent. Firstly, formulas for the derivatives and normal vectors of non-rational B-spline and NURBS are proved based on de BOOR’s recursive formula. Compared with the existing approaches targeting at the non-rational B-spline basi...
متن کاملA linear time algorithm for testing maximal 1-planarity of graphs with a rotation system
A graph is 1-planar if it can be drawn in the plane such that each edge is crossed at most once. 1-planarity is known NP-hard, even for graphs of bounded bandwidth, pathwidth, or treewidth, and for near-planar graphs in which an edge is added to a planar graph. On the other hand, there is a linear time 1-planarity testing algorithm for maximal 1-planar graphs with a given rotation system. In th...
متن کاملCPU Extensions for Accelerating Combinatorial Optimization Problems
Combinatorial optimization (CO) problems are widespread in computer science, but only a small part of them can be solved in reasonable time. Heuristic algorithms are used to accelerate solving these, mostly NP-hard, problems like allocation or partitioning. This is a trade-off between speed and optimality, as there is no guarantee to find the best solution. In order to speed up heuristic algori...
متن کاملPacking identical simple polygons is NP-hard
Given a small polygon S, a big simple polygon B and a positive integer k, it is shown to be NP-hard to determine whether k copies of the small polygon (allowing translation and rotation) can be placed in the big polygon without overlap. Previous NP-hardness results were only known in the case where the big polygon is allowed to be non-simple. A novel reduction from Planar-Circuit-SAT is present...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- IEEE Trans. Computers
دوره 42 شماره
صفحات -
تاریخ انتشار 1993