Claude Greengard

Bio: Claude Greengard is an academic researcher from IBM. The author has contributed to research in topics: Vortex & Vorticity. The author has an hindex of 15, co-authored 32 publications receiving 1415 citations. Previous affiliations of Claude Greengard include Courant Institute of Mathematical Sciences.

On Vortex Methods

Abstract: We give error estimates for fully discretized two- and three-dimensional vortex methods and introduce a new wy of evaluating the stretching of vorticity in three-dimensional vortex methods. The convergence theory of Beale and Majda is discussed and a simple proof of Cottet’s consistency result is presented. We also describe how to obtain accurate two-dimensional vortex methods in which the initial computational points are distributed on the nodes of nonrectangular grids, and compare several three-dimensional vortex methods.

System for protection of goods against counterfeiting

Abstract: In order to verify the authenticity of manufactured goods, a smart tag is attached to the goods containing encrypted authentication information, such as a serial number, a description of the good's physical appearance or chemical decomposition, its color, or digital images of the good etc. The encryption procedure comprises public/private key encryption with zero-knowledge protocols. Zero knowledge protocols allow a smart tag to be authenticatable and yet be duplication resistant by allowing the verifying agent to convince him/herself that the smart tag is authentic without revealing its authentication information. The verification procedure can be done using a reader at a point of sale (POS) machine equipped with the appropriate public key and zero-knowledge protocols to decrypt the authentication information. A printed version of the serial number or other authentication information may be placed on the goods in human readable form to quickly verify the information electronically read from the smart tag. With the present invention, only the manufacturer can create such smart tags with the associated data thus making it virtually impossible to pass off a counterfeit good as authentic. In addition to authenticating counterfeit goods, the present invention can be used to detect authentic goods being sold in a parallel market.

Event-recorder for transmitting and storing electronic signature data

Abstract: An electronic event recorder for attachment to a vehicle is provided which can broadcast encrypted signature and data, thereby leaving behind an electronic version of a “fingerprint” in the event of an accident or traffic violation. The fingerprint, captured by an external data acquisition system or another vehicle so equipped, provides a history of events related to the vehicle. The event recorder is preferably integrated on a smart card and housed in a tamper proof casing. In a first mode of operation, monitoring stations along the roadways periodically send an interrogation signal, such as when radar detects that the vehicle is speeding. Upon receiving the interrogation signal the smart card transmits the vehicle's signature information to the monitoring station where it is time and date stamped along with the speed of the vehicle. In a second mode of operation, when a sensor detects a sudden or violent acceleration or deceleration, such as occurs during a collision, a smart card mounted in each car will exchange signature information automatically. This is particularly useful when the collision occurs in a parking lot when one of the hit vehicles is typically unattended.

Method and apparatus for securely determining aspects of the history of a good

Abstract: The present invention provides methods and apparatus to detect and reliably record the physical history of a product including effects due to one or more of the following: 1) product use 2) handling 3) tampering and 4) environment of the product (as changes in the environment, such as excessive temperatures, humidity, or shocks, can result in degradation to a product) The apparatus includes a “smart card”, or, more generally, “smart token”, in combination with one or more sensors which record the external influences on the product and/or the environment and records those changes in an encrypted form This information can then be verified by any individual who is equipped with a (possibly public) decryption key, but capability to modify this information, depending on the application, is restricted to those with access to the encrypting key Furthermore, the apparatus contains authentication information which can be reliably verified, in particular to confirm that the apparatus is attached to the product it supposed to be attached to

Method and system for authenticating objects and object data

Abstract: A system and method for authenticating an image of an object, include at least one identifier associated with the object, a receiver for interrogating the at least one identifier to produce identification information, a camera system for recording an image from the object including the at least one identifier, and a composite generator for encoding the identification information from the receiver along with the image acquired by the camera system, to produce composite data.

Information record infrastructure, system and method

Abstract: A method of maintaining digital medical records, comprising a step of receiving a medical transaction record (102), encrypted with a key in accordance with a patient-file association. Also comprising a step of accessing the encrypted medical transaction record according to a patient association with the record (111). And further comprising a step of re-encryption of the encrypted accessed medical transaction record with a key associated with an intended recipient of the medical record. The system and method according to the present invention presents a new business model for creation, maintenance, transmission, and use of medical records. The invention also allows financial burdens to be reallocated optimally and equitably, resulting in decreased overall societal cost and providing a successful business model for a database proprietor. Secure entrusted medical records are held in trust by an independent third party on behalf of the patient (113), and serve the medical community at large. Separately encrypted record elements may be aggregated as an information polymer.

System and method for secure three-party communications

Abstract: A system and method for communicating information between a first party and a second party, comprising the steps of receiving, by an intermediary, an identifier of desired information and accounting information for a transaction involving the information from the first party, transmitting an identifier of the first party to the second party, and negotiating, by the intermediary, a comprehension function for obscuring at least a portion of the information communicated between the first party and the second party. The data transmission may be made secure with respect to the intermediary by providing an asymmetric key or direct key exchange for encryption of the communication between the first and second party. The data transmission may be made secure with respect to the second party by maintaining the information in encrypted format at the second party, with the decryption key held only by the intermediary, and transmitting a secure composite of the decryption key and a new encryption key to the second party for transcoding of the data record, and providing the new decryption key to the first party, so that the information transmitted to the first party can be comprehended by it.

Adaptive pattern recognition based control system and method

Abstract: An adaptive interface for a programmable system, for predicting a desired user function, based on user history, as well as machine internal status and context. The apparatus receives an input from the user and other data. A predicted input is presented for confirmation by the user, and the predictive mechanism is updated based on this feedback. Also provided is a pattern recognition system for a multimedia device, wherein a user input is matched to a video stream on a conceptual basis, allowing inexact programming of a multimedia device. The system analyzes a data stream for correspondence with a data pattern for processing and storage. The data stream is subjected to adaptive pattern recognition to extract features of interest to provide a highly compressed representation that may be efficiently processed to determine correspondence. Applications of the interface and system include a video cassette recorder (VCR), medical device, vehicle control system, audio device, environmental control system, securities trading terminal, and smart house. The system optionally includes an actuator for effecting the environment of operation, allowing closed-loop feedback operation and automated learning.

Navier-stokes, fluid dynamics, and image and video inpainting

Abstract: Image inpainting involves filling in part of an image or video using information from the surrounding area. Applications include the restoration of damaged photographs and movies and the removal of selected objects. We introduce a class of automated methods for digital inpainting. The approach uses ideas from classical fluid dynamics to propagate isophote lines continuously from the exterior into the region to be inpainted. The main idea is to think of the image intensity as a 'stream function for a two-dimensional incompressible flow. The Laplacian of the image intensity plays the role of the vorticity of the fluid; it is transported into the region to be inpainted by a vector field defined by the stream function. The resulting algorithm is designed to continue isophotes while matching gradient vectors at the boundary of the inpainting region. The method is directly based on the Navier-Stokes equations for fluid dynamics, which has the immediate advantage of well-developed theoretical and numerical results. This is a new approach for introducing ideas from computational fluid dynamics into problems in computer vision and image analysis.