In the datacenter rented to Internet Service Providers (ISPs), the low utilization of racks can seriously affect ISPs’ benefit because the ISPs are charged by “rack per year” rather than servers. Based on our analysis about the utilization data from production systems, we find that the over-provisioning of power results in low power utilization, which potentially decreases rack utilization as w...

The majority of works in distributed storage networks assume a simple network model with a collection of identical storage nodes with the same communication cost between the nodes. In this paper, we consider a realistic multi-rack distributed data storage network and present a code design framework for this model. Considering the cheaper data transmission within the racks, our code construction...

The main result of this paper is a new classification theorem for links (smooth embeddings in codimension 2). The classifying space is the rack space and the classifying bundle is the first James bundle. We investigate the algebraic topology of this classifying space and report on calculations given elsewhere. Apart from defining many new knot and link invariants (including generalised James-Ho...

The nonlinear dynamics of a cylindrical pinion that is kept at a distance from a vibrating rack is studied, and it is shown that the lateral Casimir force between the two corrugated surfaces can be rectified. The effects of friction and external load are taken into account, and it is shown that the pinion can do work against loads of up to a critical value, which is set by the amplitude of the ...

A multi-state latching translation stage is demonstrated using microelectromechanical systems technology. The mechanism is fabricated in bonded silicon-on-insulator material with an 85 μm thick bonded layer, by single-layer patterning, deep reactive ion etching, undercutting and metallization. The table position can be continuously adjusted by electrothermal buckling mode actuators or latched i...

Housing systems for laboratory animals have been developed over a long time. Micro-environmental systems such as positive, individually ventilated caging systems and forced-air-ventilated systems are increasingly used by many researchers to reduce cross contamination between cages. There have been many investigations of the impact of these systems on the health of animals, the light intensity, ...

A rack is a set X equipped with a bijective, self-right-distributive binary operation, and a quandle is a rack which satisfies an idempotency condition. In this paper, we further develop the theory of rack and quandle modules introduced in [8], in particular defining a tensor product ⊗X , the notion of a free X –module, and the rack algebra (or wring) ZX . We then apply this theory to define ho...

Abstract: Rainfall runoff collection in ephemeral streams is an objective in semi-arid zones. Rack intake systems are proposed to collect these flash floods with intensive sediment transport. The design parameters address the problem of clogging the spacing between bars. Experiments for two different void ratio racks are shown. Flows, longitudinal slopes in the rack, and water with three gravel...

The greater fluctuations in motor output that are often exhibited by old adults can be reduced with strength training. The purpose of the study was to determine the effect of strength and steadiness training by old adults on fluctuations in force and position during voluntary contractions with the quadriceps femoris muscle. Healthy old adults (65-80 yr) completed 16 wk of heavy-load (80% of max...