A construction for balancing non-binary sequences based on gray code prefixes

Abstract: We introduce a new construction for the balancing of non-binary sequences that make use of Gray codes for prefix coding. Our construction provides full encoding and decoding of sequences, including the prefix. This construction is based on a generalization of Knuth’s parallel balancing approach, which can handle very long information sequences. However, the overall sequence—composed of the information sequence, together with the prefix—must be balanced. This is reminiscent of Knuth’s serial algorithm. The encoding of our construction does not make use of lookup tables, while the decoding process is simple and can be done in parallel

Hydro-chemical modelling of in situ behaviour of bituminized radioactive waste in Boom Clay

The hydro-chemical (CH) interaction between swelling Eurobitum bituminized radioactive waste (BW) and Boom Clay was investigated to assess the feasibility of geological disposal for the long-term management of this waste. First, the long-term behaviour of BW in contact with water was studied. A CH formulation of chemically and hydraulically coupled flow processes in porous materials containing salt crystals is discussed. The formulation incorporates the strong dependence of the osmotic efficiency of the bitumen membrane on porosity and assumes the existence of high salt concentration gradients that are maintained for a long time and that influence the density and motion of the fluid. The impacts of temporal and spatial variations of key transport parameters (i.e. osmotic efficiency (s), intrinsic permeability (k), diffusion, etc.) were investigated. Porosity was considered the basic variable. For BW porosity varies in time because of the water uptake and subsequent processes (i.e. dissolution of salt crystals, swelling of hydrating layers, compression of highly leached layers). New expressions of s and k describing the dependence of these parameters on porosity are proposed. Several cases were analysed. The numerical analysis was proven to be able to furnish a satisfactory representation of the main observed patterns of the behaviour in terms of osmotic-induced swelling, leached mass of NaNO3 and progression of the hydration front when heterogeneous porosity and crystal distributions have been assumed. Second, the long-term behaviour of real Eurobitum drums in disposal conditions, and in particular its interaction with the surrounding clay, was investigated. Results of a CH analysis are presented.Peer ReviewedPostprint (published version

Encoding and Decoding of Balanced q-ary sequences using a gray code prefix

Abstract: Balancing sequences over a non-binary alphabet is considered, where the algebraic sum of the components (also known as the weight) is equal to some specific value. Various schemes based on Knuth’s simple binary balancing algorithm have been proposed. However, these have mostly assumed that the prefix describing the balancing point in the algorithm can easily be encoded. In this paper we show how non-binary Gray codes can be used to generate these prefixes. Together with a non-binary balancing algorithm, this forms a complete balancing system with straightforward and efficient encoding/decoding

Construction of efficient q-ary balanced codes

Abstract : Abstract—Knuth proposed a simple scheme for balancing codewords, which was later extended for generating q-ary balanced codewords. The redundancy of existing schemes for balancing q-ary sequences is larger than that of the full balanced set which is the minimum achievable redundancy. In this article, we present a simple and efficient method to encode the prefix that results in less redundancy for the construction of q-ary balanced codewords

On the improvement of the Knuth’s redundancy algorithm for balancing codes

Abstract: A simple scheme was proposed by Knuth to generate balanced codewords from a random binary information sequence. However, this method presents a redundancy which is twice as that of the full sets of balanced codewords, that is the minimal achievable redundancy. The gap between the Knuth’s algorithm generated redundancy and the minimal one is significantly considerable and can be reduced. This paper attempts to achieve this goal through a method based on information sequence candidates

Binary balanced codes approaching capacity

Abstract: In this paper, the construction of binary balanced codes is revisited. Binary balanced codes refer to sets of bipolar codewords where the number of “1”s in each codeword equals that of “0”s. The first algorithm for balancing codes was proposed by Knuth in 1986; however, its redundancy is almost two times larger than that of the full set of balanced codewords. We will present an efficient and simple construction with a redundancy approaching the minimal achievable one

Design and implementation of a real-time tracking and telemetry system for a solar car

Abstract: It is very critical for solar racers to achieve a the real time tracking of their solar vehicle during any race. The system is made of the real time visualisation of the video feedback of the car from the escort vehicle, the location of the car on the google maps as it is racing and its velocity. The real time video feedback of the race could be retrieved from the cloud for broadcasting purposes. The main advantage of this system is the wireless link communication which was achieved for distance transmission, coupled to a very reliable and robust Desktop Application for data sensor display purposes