Low uniform versions of NC
نویسندگان
چکیده
In the setting known as DLOGTIME-uniformity, the fundamental complexity classes AC ⊂ ACC ⊆ TC ⊆ NC have several robust characterizations. In this paper we refine uniformity further and examine the impact of these refinements on NC and its subclasses. When applied to the logarithmic circuit depth characterization of NC, some refinements leave NC unchanged while others collapse NC to NC. Thus we study refinements of other circuit characterizations of NC. In the case of the AC(A5) characterization of NC , where A5 is the NC-complete word problem of the group A5, our refinements collapse NC to a subset of the regular languages. For the AC(D+) characterizations of NC, where D+ is the NC-complete language capturing the formula value problem, interestingly, these refinements scale down to circuits with linear fan-in. In particular, the latter refinements bring to the fore two classes, denoted FO[<]-uniform AC(D+)LIN and FO[<]uniform TCLIN , whose separation may be within the reach of current lower bound techniques, and whose separation would amount to distinguishing the power of a MAJ gate from that of a D+ gate.
منابع مشابه
Effect of combination of high-dose phytase, citric acid and carbohydrases on performance of broiler chickens fed wheat-canola meal-based diets with very low content of non-phytate phosphorus
An experiment was conducted, from 22 to 42-d-post-hatch, to evaluate the effect of different combinations of carbohydrases (CHS), citric acid (CA) and high-dose phytase in wheat-canola meal-based diets with very low content of non-phytate phosphorus (NPP) on growth performance, plasma calcium (Ca) and P and tibia ash (TA) content of broiler chickens. One hundred and ninety two 21-d-old male chi...
متن کاملComparability of Computer-based and Paper-based Versions of Writing Section of PET in Iranian EFL Context
Computer technology has provided language testing experts with opportunity to develop computerized versions of traditional paper-based language tests. New generations of TOEFL and Cambridge IELTS, BULATS, KET, PET are good examples of computer-based language tests. Since this new method of testing introduces new factors into the realm of language assessment ( e.g. modes of test delivery, famili...
متن کاملAn experimental investigation of novel hybrid epoxy/glass fibers nanocomposite reinforced with nanoclay with enhanced properties for low velocity impact test
The application of nanoparticles in order to enhance the composites properties has been recently attracted many researchers' attentions. To increase the mechanical and physical properties of the composites, the nanoparticles have no significant effect on the weight and nanostructure of composites. One of the well-known nanoparticles is the Nanoclay (NC) that have been widely used in industries ...
متن کاملNon-Uniform Automata Over Groups
A new model, non-uniform deterministic finite automata (NUDFA’s) over general tinite monoids, has recently been developed as a strong link between the theory of finite automata and low-level parallel complexity. Achievements of this model include the proof that width 5 branching programs recognize exactly the languages in non-uniform NC’, NUDFA characterizations of several important subclasses ...
متن کاملRealization Methodology of a 5-axis Spline Interpolator in an Open CNC System
By making use of the advantages of non-uniform rational B-spline (NURBS) curves to represent spatial curves, an instruction format with double NURBS curves suitable for 5-axis coordinated real-time interpolation is presented to replace the current 5-axis coordinated linear interpolation method defective in low-speed, low-accuracy and enormous numerical control (NC) files in sculptured surface m...
متن کامل