A race condition is a situation where two threads manipulate a data structure simultaneously, without synchronization. Race conditions are common errors in multithreaded programming. They often lead to unintended nondeterminism and wrong results. Moreover, they are notoriously hard to diagnose, and attempts to eliminate them can introduce deadlocks. In practice, race conditions and deadlocks ar...

The concept of Grid computing has been in the making since the 1960’s, but it took quite some time up to the late 1990’s, with the advent of faster networks and better understanding of distributed computing, that some of those concepts were realized. Even now, the world’s computer networks are very primitive as compared to other networks, such as the electrical power grid, the telephone network...

The paper aims at creating an authentication algorithm using visual cryptography that creates a fool-proof lock-key mechanism wherein a lock can be opened by its paired key only and the key cannot be duplicated. In our proposed mechanism we uses a lock and a key, both is one part of given secret image. Every lock-key pair has one associated unique image. The lock is just like a safe door which ...

Fine-grained lock protocols should allow for highly concurrent transaction processing on XML document trees, which is addressed by the taDOM lock protocol family enabling specific lock modes and lock granules adjusted to the various XML processing models. We have already proved its operational flexibility and performance superiority when compared to competitor protocols. Here, we outline our ex...

The bidirectional replication of a circular chromosome by many bacteria necessitates proper termination to avoid the head-on collision of the opposing replisomes. In Escherichia coli, replisome progression beyond the termination site is prevented by Tus proteins bound to asymmetric Ter sites. Structural evidence indicates that strand separation on the blocking (nonpermissive) side of Tus-Ter tr...

in the present paper the behavior of an elastically mounted cylinder in low and high mass-damping ratio is investigated. for high mass-damping ratio, a classical wake oscillator model is used. at the first, by neglecting all damping and nonlinear terms of this model, the possibility of using a linear model for determination of the lock-in range and the dominant mode is investigated. then, witho...

a new method for increasing ldr in deep drawing is application of anti-lock braking system (abs) on blank holder. in this method, instead of applying a constant force on blank and control the metal flow, the abs system holds and releases the blank several times (20 to 50 times) which results increasing ldr. this study investigates the effect of different parameters of abs on improving the condi...

Spin locks are a synchronization mechanisms used to provide mutual exclusion to shared software resources. Spin locks are used over other synchronization mechanisms in several situations, like when the average waiting time to obtain the lock is short, in which case the probability of getting the lock is high, or when it is no possible to use other synchronization mechanisms. In this paper, we s...

We consider various techniques for implementing shared objects and for accounting for objectsharing overheads in Pfair-scheduled multiprocessor systems. We primarily focus on the use of lock-free objects, though some lock-based alternatives are briefly considered as well. Lock-free objects are more economical for implementing relatively simple objects such as buffers, stacks, queues, and lists;...

Although one is unlikely to ever want to brute-force an Android lock pattern, many do wonder about the relative strength of the lock pattern versus a multi-digit personal identification number (PIN). It becomes obvious pretty quickly that there are many more lock patterns than the 10,000 possible four-digit PINs. Figure 1 Android lock pattern screen But, how many lock patterns are there? The of...