Discrete Green’s functions are the inverses or pseudo-inverses of combinatorial Laplacians. We present compact formulas for discrete Green’s functions, in terms of the eigensystems of corresponding Laplacians, for products of regular graphs with or without boundary. Explicit formulas are derived for the cycle, torus, and 3-dimensional torus, as is an inductive formula for the t-dimensional toru...

We study the resilience of the classical pseudo-random generator (PRG) of Nisan [Nis92] against space-bounded machines that make multiple passes over the input. Our motivation comes from the derandomization of BPNC. Observe that if for every log-space machine that reads its input n times there is a PRG fooling this machine, then in particular we fool NC circuits. Nisan’s PRG is known to fool lo...

the fuel cells are distinguished as generating of green allocable energy and are electrochemical devices of low environmental impact. porous nanocrystalline strontium-doped lanthanum manganite la0.8sr0.2mno3 (lsm) cathode materials were prepared by mechanochemical route in various grinding times. carbon black was employed to produce pores. the formation of lsm single phase was studied by x-ray ...

This paper proposes a new addition method, which can be applied to reduce the hardware cost of LDPC decoders using log-SPA, which traditionally has the best lowest bit error rate (BER) but the highest hardware requirement. The proposed quasi-binary weighting addition can be simply implemented by OR gates. With auxiliary pseudo-carry circuit, the BER performance can reach a fair level. In the lo...

   In this study, the change of porosity and roughness of carbon nanostructures, including fullerenes, carbon nanotubes and graphene was investigated according to oxidation process. The effect of oxidation was more sensible on smoother surface of nanostructures. Oxidation increases surface roughness of graphene up to 5.2% and porosity up to 35.2%. While, roughness of hummers graphene is 13....

A mathematical model is developed describing the natural smoldering of logs. It is considered the steady onedimensional propagation of infinitesimally thin fronts of drying, pyrolysis, and char oxidation in a horizontal semi-infinite log. Expressions for the burn rates, distribution profiles of temperature, and positions of the drying, pyrolysis, and smoldering fronts are obtained in terms of t...

Let N be a single-source single-sink ow network with n nodes, m arcs, and positive arc costs. We present a pseudo-polynomial algorithm that computes a maximum ow of minimum cost for N in time O(3=4 m p log n), where is the cost of the ow. This improves upon previously known methods for networks where the minimum cost of the ow is small. We also show an application of our ow algorithm to a well-...

We present a new static dictionary that is very fast and compact, while also extremely easy to implement. A combination of properties make this algorithm very attractive for applications requiring large static dictionaries: 1. High performance, with membership queries taking O(1)-time with a near-optimal constant. 2. Continued high performance in external memory, with queries requiring only 1-2...

The possibility of obtaining solid ingots (without gas porosity in the volume) from high-nitrogen steel Fe-Cr-Mo-N-C system by method self-propagating high-temperature synthesis under nitrogen pressure is shown present paper. It has been established that with an increase mass fraction carbon 0.09 % to 0.30 as-cast metal, hardness metal increases. At same time, structural-phase composition consi...