Quantum coins

One of the earliest cryptographic applications of quantum information was to create quantum digital cash that could not be counterfeited. In this paper, we describe a new type of quantum money: quantum coins, where all coins of the same denomination are represented by identical quantum states. We state desirable security properties such as anonymity and unforgeability and propose two candidate quantum coin schemes: one using black box operations, and another using blind quantum computation.

Confronting expectation in grade 4: Tossing two coins

This study focuses on the experiences of 91 Grade 4 students who had been introduced to expectation and variation through trials of tossing a single coin many times. They were then given two coins to toss simultaneously and asked to state their expectation of the chances for the possible outcomes, in a similar manner expressed for a single coin. This paper documents the journey of the students in discovering that generally their initial expectation for two coins was incorrect and that despite variation, a large number of tosses could confirm a new expectation.

Leo Baeck Medal awarded to Axel Springer Coins and Medals

"Presented to Axel Springer devoted friend and generous benefactor of the Leo Baeck Institute 1977"

Hanukka Circulation Coins Set

5 coin set: 5 Agorot; 10 Agorot; 1/2 New Sheqel; 1 New Sheqel; 5 New Sheqalim. All of the coins have on the obverse side Hanukkiyot and word Hanukka.

Israel Official Uncirculated Coins Set

8 coin set. 1 Sheqel; 5 Sheqalim; 10 Sheqalim; 2 times 50 Sheqalim-one with a portrait of David Ben-Gurion on the reverse side, one normal coin; 3 times 100 Sheqalim-one with a portrait of Ze'ev Jabotinsky on the reverse side, one with Hanukkah lamp on the obverse side, one normal plain coin.

Automatic attribution of ancient Roman imperial coins

Classification of coins is an important but laborious aspect of numismatics - the field that studies coins and currency. It is particularly challenging in the case of ancient coins. Due to the way they were manufactured, as well as wear from use and exposure to chemicals in the soil, the same ancient coin type can exhibit great variability in appearance. We demonstrate that geometry-free models of appearance do not perform better than chance on this task and that only a small improvement is gained by previously proposed models of combined appearance and geometry. Thus, our first major contribution is a new type of feature which is efficient in terms of computational time and storage requirements, and which effectively captures geometric configurations between descriptors corresponding to local features. Our second contribution is a description of a fully automatic system based on the proposed features, which robustly localizes, segments out and classifies coins from cluttered images. We also describe a large database of ancient coins that we collected and which will be made publicly available. Finally, we report the results of empirical comparison of different coin matching techniques. The features proposed in this paper are found to greatly outperform existing methods.

Reading ancient coins: automatically identifying denarii using obverse legend seeded retrieval

The aim of this paper is to automatically identify a Roman Imperial denarius from a single query photograph of its obverse and reverse. Such functionality has the potential to contribute greatly to various national schemes which encourage laymen to report their finds to local museums. Our work introduces a series of novelties: (i) this is the first paper which describes a method for extracting the legend of an ancient coin from a photograph; (ii) we are also the first to suggest the idea and propose a method for identifying a coin using a series of carefully engineered retrievals, each harnessed for further information using visual or meta-data processing; (iii) we show how in addition to a unique standard reference number for a query coin, the proposed system can be used to extract salient coin information (issuing authority, obverse and reverse descriptions, mint date) and retrieve images of other coins of the same type.

Non-Contact Documentation of Physical Characteristics of Ecstasy Tablets, Hemp Coins, and Imprint Punches by using 3D Optical Surface Scanning

The description of seized illicit ecstasy tablets and other pressed drug products is an important step in casework. The physical and visual analysis and the description of the characteristics can be employed for intelligence purposes. Besides photography and manual measurements of dimensions, some optical instruments are employed for detailed measurements of physical characteristics. In this work, the method of 3D surface digitizing is introduced as a suitable tool for highly accurate documentation of small objects, especially for pressed drug products. The resulting detailed information about the geometry, and the results of an automatic comparison of apparently uniform tablets and coins with punches, can support drug intelligence.