We consider the problem of locating a light coin out of a set containing n coins, n ? 1 of which have the same weight. The weighing device is a balance with r 2 pans and, when r equally sized subset of coins are weighted, it indicates the eventual subset containing the light coin. We give an algorithm to nd the counterfeit coin that requires the minimum possible average number of weighings. All...

We consider the problem of finding edges of a hidden weighted graph using a certain type of queries. Let G be a weighted graph with n vertices. In the most general setting, the n vertices are known and no other information about G is given. The problem is finding all edges of G and their weights using additive queries, where, for an additive query, one chooses a set of vertices and asks the sum...

Last time we introduced the notion of interactive proof systems which models computation as a result of interaction between two parties. We defined public/private coin protocols, and showed that the graph non-isomorphism problem admits an interactive proof using private coins, as well as one using public coins. Today we will continue our discussion of interactive proof systems. We will study th...

This set of notes explains the process that Prof. Jones used to develop the FSM for the lab. The lab simulates a vending machine mechanism for automatically identifying coins (dimes and quarters only), tracking the amount of money entered by the user, accepting or rejecting coins, and emitting a signal when a total of 35 cents has been accepted. In the lab, we will only drive a light with the “...

The second season of the archaeological survey of Qeshm Island was conducted during the winter of 2012, during which the team identified a total of 138 sites. The preliminary analysis of the ceramic assemblage from these sites suggests that 5 sites date to the 3rd millennium B.C.(Bronze Age) and represent the earliest in the directory. The remainder includes 3 Iron Age, 4 Achaemenid, 23 Parthia...

We provide a mechanism that uses two biased coins and implements any distribution on a finite set of elements, in such a way that even if the outcomes of one of the coins is determined by an adversary, the final distribution remains unchanged. We apply this result to show that every quitting game in which at least two players have at least two continue actions has an undiscounted ε-equilibrium,...

In a 9-hour experiment we evaluated learning performance based on exploring the shortest paths in hyperlink network of Wikipedia online encyclopedia. Relying on network of 35688 unique hyperlinks in three separate learning sessions of 20 minutes students read series of 62 sentences built by using 22 unique hyperlinks that form the eleven shortest paths and answered pre-test and post-test multip...

Zcash is a fork of Bitcoin with optional anonymity features. While transparent transactions are fully linkable, shielded transactions use zero-knowledge proofs to obscure the parties and amounts of the transactions. First, we observe various metrics regarding the usage of shielded addresses. Moreover, we show that most coins sent to shielded addresses are later sent back to transparent addresse...

In 2013, Baseri et al. proposed an untraceable off-line electronic cash scheme from the RSA cryptosystem. They used a method that injects the expiration date and the spenders identity onto the coin to prevent double spending. The authors claimed that the scheme provides the properties of anonymity, unforgeability, double spending detection, and date attachability. Unfortunately, we find that th...