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Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
redundant manipulator RAID0 being the only one that does not include redundancy. redundant manipulator the manipulator is called redundant if more degrees of mobility are available than degrees of freedom required for the execution of a given task. See also differential kinematics, redundancy. redundant number system the system in which the numerical value could be represented by more than one bit string. Reed switch a magnetomechanical device composed of two thin slats of ferromagnetic material within a hermetically sealed capsule that attract each other when an external magnetic field (from an electromagnet or permanent magnet) induces opposite poles at the overlapping ends of both slats. Reed-Solomon code an extension of BAH codes to nonbinary alphabets developed by Driving Reed and Gustave Solomon independently of the work by Bose, Chaudhuri, and Hocquenghem. Arguably, the most widely used of any forward error control code. reentrancy the characteristic of a block of software code that, if present, allows the code in the block to be executed by more than one process at a time. reentrant a program that uses concurrently exactly the same executable code in memory for more than one invocation of the program (each with its own data), rather than separate copies of a program for each invocation. The read and write operations must be timed so that the correct results are always available and the results produced by an invocation are not overwritten by another one. reference black level picture signal level corresponding to a specified maximum limit for black peaks. reference frame See base frame.
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Published in Phillip A. Laplante, Dictionary of Computer Science, Engineering, and Technology, 2017
reentrant code code which does not maintain any local state in such a way that a concurrent execution would be affected. Contrast with serially reusable, recursive. See also reentrant.
Security analysis of smart contract based rating and review systems: the perilous state of blockchain-based recommendation practices
Published in Connection Science, 2022
Jitendra Singh Yadav, Narendra Singh Yadav, Akhilesh Kumar Sharma
If a function in contract P interacts with another untrusted contract Q, a recursive call from P into Q is possible before completing this interaction and can leave the account empty. The DAO attack exploited this vulnerability and accounted for 60 million US Dollars (Luu et al., 2016). Accuracy in the recommender systems depends on the number of user ratings and reviews. The current systems employ a reward mechanism to increase user interaction by giving monetary incentives. So, e.g. the smart contract function for transferring rewards recursively called from an owner contract may be susceptible to the reentrancy attack. The Reentrancy attack is of two types: the first type is a single function Reentrancy attack where the vulnerable function and the function intended to call recursively are the same. The second type is a cross-functional Reentrancy attack, where both functions are not the same, and the vulnerable function shares its state with the function exposed to an attacker.