The main objective of this work was to design a novel device for compaction of metal powders so that the green parts could be ejected with applying a negligible force and without the need for any lubricant in either an admixed form or applied to the die wall. For this purpose a 40 mm diameter one-piece die was envisaged which would elastically contracted 0.076 mm before compaction and after com...

The compaction of soils used for crop production is becoming an increasingly important consideration in South Africa following the shift towards reduced tillage and increased mechanisation of in-season operations and harvesting. The intensification of dairying has also been found to have a deleterious effect on soil quality, particularly in terms of compaction by trampling, which results in los...

Soil compaction reduces rooting, infiltration, water storage, aeration, drainage, and crop growth. Soil compaction has been studied intensively for more than a century, and yet we still struggle with the effect that soil compaction has on crop production and the environment. In this article, we attempt to present the primary causes of soil compaction including trafficking weak soil, excessive l...

Stream compaction is an important parallel computing primitive that produces a reduced (compacted) output stream consisting of only valid elements from an input stream containing both invalid and valid elements. Computing on this compacted stream rather than the mixed input stream leads to improvements in performance, load balancing, and memory footprint. Stream compaction has numerous applicat...

Summarization is an important problem in many domains involving large datasets. Summarization can be essentially viewed as transformation of data into a concise yet meaningful representation which could be used for efficient storage or manual inspection. In this paper, we formulate the problem of summarization of a large dataset of transactions as an optimization problem involving two objective...

The influence of compaction water content on the structure has been well known forclayey soils, but has never been studied for granular materials. In this paper the structure of a nonplastictill and the effect of compaction moisture is investigated by means of water retention curvestudy, scanning electron microscopy and mercury intrusion porosimetry tests. The results show thatwhen compacted on...

Interphase chromatin compaction well above the 30-nm fiber is well documented, but the structural motifs underlying this level of chromatin folding remain unknown. Taking a reductionist approach, we analyzed in mouse embryonic stem (ES) cells and ES-derived fibroblasts and erythroblasts the folding of 10-160-megabase pair engineered chromosome regions consisting of tandem repeats of bacterial a...