On Multifold MDS and Perfect Codes That Are Not Splittable into Onefold Codes

The union of disjoint MDS (or perfect) codes with distance 2 (respectively, 3) is always an -fold MDS (perfect) code. The converse is shown to be incorrect. Moreover, if k is a multiple of 4 and n + 1 16 is a power of two, then a k/2-fold k-ary MDS code of length m 3 and an (n + 1)/8-fold perfect code of length n exist from which no MDS (perfect) code can be isolated.     

Silica Extraction from Geothermal Solution

Experiments are conducted for silica precipitation from hydrothermal solution by cryogenic technology. For silica precipitated, the physico-chemical characteristics ensuring reduction in process duration and energy expenditures are established.     

Patterns of tree-cover loss along the Indonesia–Malaysia border on Borneo

Borneo Island is experiencing rapid tree-cover loss. This loss has been quantified for the Indonesian part of the island at Landsat spatial resolution, but no recent study exists that extends across the border into Malaysia. This research focused on quantifying patterns of tree-cover loss in the Indonesia–Malaysia border zone on Borneo. The methods used for quantifying 2000–2010 tree-cover loss within 20 km on either side of the border are an internally consistent mapping algorithm used on Landsat imagery and a local indicator of spatial autocorrelation to quantify the concentration of loss. Within the 20 km zone on either side of the border, tree-cover loss rates in lowlands were high in the two countries (19.8% and 14.4%, in Indonesia and Malaysia, respectively), but rates in the Malaysian uplands were an order of magnitude higher than in the Indonesian uplands (2.95% and 0.25%, respectively). Clusters of tree-cover loss in the Malaysian uplands were considerably larger than in the Indonesian uplands.     

Application of the microwave technique for burning-rate measurement in high-energy composite materials

A facility designed to determine the current burning rate of high-energy composite materials is described. Methodical aspects of processing the measured information are considered. Results on the effect of humidity of the samples on their burning rate are presented. Translated fromFizika Goreniya i Vzryva, Vol. 36, No. 1, pp. 79–82, January–February, 2000.     

Figurate superlattices in the classical problem of signal filtering against the noise background on the basis of a cellular nonlinear network

A new type of multilayer semiconductor structures (figurate superlattices) that can be used in construction of resonant-tunneling diode components has been proposed and investigated. The superlattice advantages over structures with standard nonlinear current-voltage characteristics are discussed as applied to the classical filtering problem on the basis of a cellular nonlinear network. It is demonstrated that the absolutely new, so-called fractal cellular nonlinear networks can be developed.