Abstract: A processor is provided with a first set of digital information that includes a first structured representation of a document. From the first set of digital information, the processor produces a second set of digital information that includes a second structured representation of the document. The second structured representation is a lossless representation and includes a set of tokens and a set of positions. At least one token in the plurality of tokens has an associated semantic label which may be a character code associated with various font types in the second structured representation of the document. The semantic label may be obtained and stored in the second structured representation of the document by a computer program. The first and second representations may be resolution dependent structured representations and have, respectively, first and second characteristic resolutions. The first representation, but not the second, is provided in digital form to an untrusted recipient.

Abstract: Tamper-evident electric paper is made of two sheets of electric paper bonded together, the bottom sheet of which includes a pattern. Any attempt to erase a writing on the top sheet of electric paper results in the pattern on the bottom sheet of electric paper being erased. Therefore any tampering by erasure of a writing on the tamper-evident electric paper is revealed by the absence of a portion of the pattern on the bottom sheet of electric paper. Single sheet tamper-evident electric paper has a complex pattern, such as an encryption, printed on a single sheet of electric paper. Any attempt to erase a writing on the electric paper also erases a portion of the encryption, thereby providing evidence of tampering.

Abstract: A processor is provided with a first set of digital information that includes a first structured representation of a document. From the first set of digital information, the processor produces a second set of digital information that includes a second structured representation of the document. The second structured representation is a lossless representation and includes a set of tokens and a set of positions. At least one token in the plurality of tokens has an associated semantic label which may be a character code associated with various font types in the second structured representation of the document. The semantic label may be obtained and stored in the second structured representation of the document by a computer program. The first and second representations may be resolution dependent structured representations and have, respectively, first and second characteristic resolutions. The first representation, but not the second, is provided in digital form to an untrusted recipient.

Abstract: A system and method for providing interactive computer assisted teaching. The system is premised on and extends the ubiquitous nature of paper in classroom environments to be an interaction medium with a computer based system. By utilizing intelligent form and embedded data processing, highly interactive and customized teaching applications can be created. A student and other members of the educational community interacts with the system by making marks on an educational material and then scanning that educational material back into the system. Intelligent forms processing techniques are used to identify the marks made and pass them on to a teaching application. The teaching application will then determine an appropriate course of interaction, which may include having a responsive educational material printed out for the student. The system provides for having a single computer in a classroom, wherein students can use a familiar medium, paper, to interact with the computer.

Abstract: A toner jet printer and method of use for printing images by manipulating individual toner particles using two-dimensional print cell arrays built by micro electro mechanical systems (MEMS) technologies. Toner particles are positioned by electrostatic forces within each print cell by either selective or non-selective filling. If selectively filled, each cell is then subjected to a mechanical force to eject the toner particles onto a paper substrate. If non-selectively filled, only those print cells corresponding to an intended image are addressed electronically to eject a toner particle from an addressed cell by mechanical forces controlled by micro actuator actuation. Single color or multiple color printing can be achieved using the same cell array.

Abstract: Qualitative reasoning for physical systems, and techniques for automatic code generation are used to automatically construct digital controllers/device drivers for electro-mechanical systems. Such construction uses models of the system's components described as finite state machines, to form a configuration space. Transitions of the configuration space are labelled as external or internal and a state of the system is identified as a desired state while other states are identified as undesirable. From this configuration space a controller is generated to drive the system to the desired state while avoiding the undesirable states.

Abstract: An expert system, such as could be used for service of a complicated physical device such as a printer or copier, exploits a knowledge base which is written in a markup language format such as SGML. The knowledge base comprises text which, if desired, can be printed out on paper to yield a traditional service manual. In addition to the typical formatting markup language tags surrounding the text of the knowledge base, hierarchical tags are provided in the electronic version of the knowledge base, to define a set of decision trees which can be accessed and navigated by an expert system. A diagnostic advisor can access specific elements of the knowledge base as needed to synthesize optimized diagnosis and repair procedures depending on an entry given by a tech rep servicing a machine. This arrangement thus supports both a printed service manual and a viewer that provides expert diagnostic advice.

Abstract: A system for controlling use and distribution of composite digital works. A digital work is comprised of a description part and a content part. The description part contains control information for the composite digital work. The content part stores the actual digital data comprising the composite digital work. The description part is logically organized in an acyclic structure, e.g. a tree structure. For a composite digital work each node of the acyclic structure represents an individual digital work or some distribution interest in the composite digital work. A node in the acyclic structure is comprised of an identifier of the individual work, usage rights for the individual digital work and a pointer to the digital work. Composite digital works are stored in repositories. A repository has two primary operating modes, a server mode and a requester mode. When operating in a server mode, the repository is responding to requests to access digital works.

Abstract: A user extensible document processing system. The extensible document processing system includes a document processing platform such as a digital copier,control forms for specifying requested services and instructions and one or more document service cards. User provided document processing services are contained on document service cards. A set of basic document processing services are provided by the document processing platform. The document processing platform includes one or more ports for coupling to document service cards, a registration device for registering services into a service taxonomy, a deregistration device for deregistering services from the service taxonomy, a service dispatcher for identifying the service to process a control form using the service taxonomy, and a scanner for creating a digital representation of a paper based document. The document processing platform registers document services upon detecting the coupling of a document services card.

Abstract: A Document Card (DocuCard) for storing documents and which is content revealing. The DocuCard is a transportable unit having a nonvolatile storage means for storing information in a digital form, a control processor for processing user initiated functions; an I/O port for interfacing to external devices for reading and writing digital information, and a user interface for allowing a user to directly interact with the DocuCard. The user interface on the DocuCard includes a display for displaying lists of functions and documents and information responsive to user invoked functions and a user input portion for allowing a user to traverse the lists of functions and documents, as well as information generated responsive to an invoked function. The control processor of the present invention include features for controlling access to documents stored therein.

Abstract: A top-down technique for character text recognition of an image comprises a left-to-right analysis of each image line. A current image portion is selected. Possible text prefixes are selected from a dictionary. The upper and lower text contours of the text prefixes are compared with a bitmap of the current image portion. A distance value is generated, indicating the quality of the comparison. The prefixes are then added to an agenda of prefixes. Based on the distance value, corresponding to the similarity of the upper shapes and lower shapes of the possible prefix to the bitmap of the image portion, a list of the text prefixes generating the best distance values is selected from the agenda. From the selected list, a new list of extended text prefixes is obtained from the dictionary and added to the agenda. The process is repeated until the current image portion ends.

Abstract: A system dynamically schedules the creation of images in an on-demand printing apparatus outputting simplex and duplex prints. For each simplex print, a simplex print block is appended to a schedule of images to be created, and for each duplex print, a duplex print block is appended to the schedule. The duplex block includes two portions, one portion for each image in the duplex print, separated by a number of pitches which can be occupied by other images. The duplex and simplex blocks are then organized in a manner which preserves the desired final sequence of prints and minimizes the number of unused image pitches in the printing apparatus. The scheduling technique can also be applied to multi-pass color printing.

Abstract: A computer program is disclosed for reclaiming unreferenced computer memory space, also known as garbage collection. The program operates in a virtual memory environment wherein user memory space is divided into pages. For each active page, a table stores the age of the oldest object on the page (A-value) and the age of the youngest object pointed to from that page (F-value). A generational partition divides the pages into "safe" pages and "threatened" pages, based on their A-values. Rescuer pages, which may contain pointers to threatened pages, are determined by comparing the F-values to the generational partition. All potential pointers on the rescuing pages are traced and the objects pointed to are marked as reachable. All objects reachable from other reachable objects are also marked. Unmarked threatened objects are de-allocated.

Abstract: An information retrieval system and method are provided in which an operator inputs one or more query words which are used to determine a search key for searching through a corpus of documents, and which returns any matches between the search key and the corpus of documents as a phrase containing the word data matching the query word(s), a non-stop (content) word next adjacent to the matching word data, and all intervening stop-words between the matching word data and the next adjacent non-stop word. The operator, after reviewing one or more of the returned phrases can then use one or more of the next adjacent non-stop-words as new query words to reformulate the search key and perform a subsequent search through the document corpus. This process can be conducted iteratively, until the appropriate documents of interest are located. The additional non-stop-words from each phrase are preferably aligned with each other (e.g., by columnation) to ease viewing of the "new" content words.

Abstract: In a collaborative system in which a body of shared data may be accessed by more than one user, a small-scale representation of the body of shared data displayed to one user includes an indication of the activities of other users. A user that is not viewing the shared data at full scale can thus obtain information about the activities of other users from a small-scale representation. The small-scale representation can indicate the type of activity, the extent or rate of changes in the shared data, the other users viewing the full-scale representation, or can show the shared data in shrunken form, indicating the parts that have been changed. The extent or rate of changes can be indicated with a quantitative indicator such as a gauge.