Showing papers on "Object (computer science) published in 1992"

Dynamic binding in a neural network for shape recognition.

Abstract: Given a single view of an object, humans can readily recognize that object from other views that preserve the parts in the original view. Empirical evidence suggests that this capacity reflects the activation of a viewpoint-invariant structural description specifying the object's parts and the relations among them. This article presents a neural network that generates such a description. Structural description is made possible through a solution to the dynamic binding problem: Temporary conjunctions of attributes (parts and relations) are represented by synchronized oscillatory activity among independent units representing those attributes. Specifically, the model uses synchrony (a) to parse images into their constituent parts, (b) to bind together the attributes of a part, and (c) to bind the relations to the parts to which they apply. Because it conjoins independent units temporarily, dynamic binding allows tremendous economy of representation and permits the representation to reflect the attribute structure of the shapes represented.

Object lifecycles: modeling the world in states

Abstract: 1. The World of Systems Analysis. 2. The Object-Oriented World. 3. A Review of Information Modeling. 4. Object Lifecycles. 5. Coordinated Lifecycles. 6. Object Processes. 7. Managing the Work. 8. External Specification. 9. Work Products of Object-Oriented Analysis. 10. Using Object-Oriented Analysis with 2167A.

Method and apparatus for manipulating computer-based representations of objects of complex and unique geometry

Abstract: The present invention provides a method and apparatus for the manipulating computer-based representations of objects of complex and unique geometry. A computer acquires data describing an object and its surroundings, constructs a computer-based three dimensional model of the object from that data, superimposes an ideal geometry on the computer-based model, and alters the ideal geometry to fit the form and function required of the reproduction. The present invention presents two embodiments for manipulating computer-based representations of three dimensional objects.

Object-Oriented Multi-Methods in Cecil

Abstract: Multiple dispatching provides increased expressive power over single dispatching by guiding method lookup using the values of all arguments instead of only the receiver. However, existing languages with multiple dispatching do not encourage the data-abstraction-oriented programming style that is encouraged by traditional single-dispatching languages; instead existing multiple-dispatching languages tend to foster a function-oriented programming style organized around generic functions. We propose an alternative view of multiple dispatching that is intended to promote a data-abstraction-oriented programming style. Instead of viewing a multi-method as “outside” of all objects, we view a multi-method as “inside” the objects for which the multi-method applies (on which it dispatches). Because objects are closely connected to the multi-methods implementing their operations, the internals of an object can be encapsulated by being accessible only to the closely-connected multi-methods. We are exploring this object-oriented view of multi-methods in the context of a new programming language named Cecil.

Introducing Objectcharts or how to use Statecharts in object-oriented design

Abstract: A notation called Objectcharts for specifying object classes is introduced. An Objectchart diagram is an extended form of a Statechart, which characterizes the behavior of a class as a state machine. The Objectchart transitions correspond to the state-changing methods that the class provides and those that it requires of other classes. Object attributes and observer methods annotate Objectchart states. Firing and postconditions are used to specify the effect of transitions on class attributes. The Objectchart notions is described through the development of an alarm clock application. How Objectcharts can be used to find subtyping inheritance relationships between classes and a systematic approach for evolving Objectchart specifications are shown. >

Event specification in an active object-oriented database

Abstract: The concept of a trigger is central to any active database. Upon the occurrence of a trigger event, the trigger is “fired”, i.e, the trigger action is executed. We describe a model and a language for specifying basic and composite trigger events in the context of an object-oriented database. The specified events can be detected efficiently using finite automata.We integrate our model with O++, the database programming language for the ode object database being developed at AT&T Bell Labs. We propose a new Event-Action model, which folds into the event specification the condition part of the well-known Event-Condition-Action model and avoids the multiple coupling modes between the event, condition, and action trigger components.

Shape transformation for polyhedral objects

Abstract: Techniques that transform one two-dimensionaf image into another have gained widespread use m recent yeara. Extending these techniques to transform pairs of 3D objects, as opposed to 2D images of the objects, providea several advsntagea, including the ability to snimate the objects independently of the transformation. This paper presents an algorithm for computing such transformations. The algorithm merges the topological structures of a pair of 3D polyhedral models into a common vertex/edgeJface network. This allows trsmsformations from one object to the other to be easily computed by interpolating between corresponding v@ex positions.

Object transferring system and method in an object based computer operating system

Abstract: An object based operating system for a multitasking computer system provides objects which represent the architecture or interrelationships of the system's resources. Access to certain objects is required in order to use corresponding resources in the system. All objects have a consistent data structure, and a consistent method of defining the operations which apply to each type of object. As a result, it is relatively easy to add new types of system objects to the operating system. The object based operating system supports multiple levels of visibility, allowing objects to be operated on only by processes with the object's range of visibility. This allows objects to be made private to a process, shared by all processes within a job, or visible to all processes within the system. An object or an entire set of objects can be moved to a higher visibility level when objects need to be shared. In addition, access to each object is controlled through an access control list which specifies the processes authorized to access the object, and the types of access that are allowed. An object with a restricted access control list can be associated with a "privileged operation", thereby restricting use of the privileged operation to those user processes authorized to access the corresponding object. Waitable objects are used to synchronize the operation of one or more processes with one another or with specified events. The system provides routines for generating new types of waitable objects without modifying the operating system's kernel.

Using extremal boundaries for 3-D object modeling

Abstract: The extremal boundaries, of 3-D curved objects are the images of special curves drawn on the object and are called rims They are viewpoint dependent and characterized by the fact that the optical rays of their points are tangential to the surface of the object The mathematics of the relationship between the extremal boundaries and the surface of the object is studied This study makes it possible to design an algorithm for detecting those boundaries in the images that are likely to be extremal Once this has been done, one can reconstruct the rims and compute the differential properties of the surface of the object along them up to the second order If a qualitative description is sufficient, the sign of the Gaussian curvature of the surface along the rim can be computed in a much simpler way Experimental results are presented on synthetic and real images The work provides a better understanding of the relationship between the apparent and real shape of a 3-D object as well as algorithms for reconstructing the local shape of such an object along the rims >

Apparatus and method for dynamic linking of computer software components

Abstract: An apparatus and method for the dynamic (execution time) linking of object oriented software components is disclosed. The present invention comprises a computer system including a set of at least two software components. This invention provides a method and means for dynamically linking object oriented software components during run time execution of the program. The present includes two main features. First, a query function is provided to allow an application component to determine, during program execution time, the name and location of library classes available for use. Second, the application component can create (instantiate) instances of derived classes of an abstract base class. The application component can manipulate the instantiated object using the abstract interface provided by the base class definition. The implementation of the present invention involves processing at two steps in the software generation cycle. First, the prior art static linker must be modified to provide processing support for the present invention at link time. Second, the main features of the present invention are performed at program execution time.

Apparatus and method for linking software modules

Abstract: An apparatus and method for interconnecting a plurality of independent software modules by means of specially configured software objects called "Input" and "Output". The software objects are implemented through library functions which include functions for making an Output object, making an Input object, adding actions to Input objects, making connections between the Input and Output objects of various software modules, sending messages from one software module to another, and receiving messages sent by another software module. The invention also provides a system for interconnecting a plurality of hardware modules, each of which may employ different internal data formats. Additionally, a novel graphical user interface is provided, whereby a user can create, destroy, inspect and/or hide connections between software modules, as well as display data flow between modules.

Object Behavior Analysis.

Abstract: Object Behavior Analysis nalysis is the study and modeling of a given problem domain, within the context of stated goals and objectives. It focuses on what a system is supposed to do, rather than how it is supposed to do it (which we consider the design aspects). In addition , it must embody the rule of traceability (why), which justifies the existence of a given result by tying it back to the stated goals and objectives. The components of the problem domain can be described as anything that end users of the system, both humans and machines, view as part of the problem context. This may include technical issues, if the users view such issues as part of the problem. • • • • • • • • • • • • • • • • We want the analysis process to be carried out in a predictable and controllable manner. In taking an object-oriented approach to analysis , our goal on completion is that we have a clear understanding of the behaviors exhibited by the system , the objects that exhibit these behaviors, the relationships among the objects, and how the objects interact with one another (the system dynamics). This must all be specified in a clear and well-defined language of object and behavior names, chosen from the problem domain. In addition, any implementation code must be traceable back to the results of the analysis. This means that the vocabulary and structures apparent in the design and implementation must clearly reflect the vocabulary and structures that result from the analysis. Object-oriented analysis endeavors to model a situation in terms of a collection of interacting entities, each of which provides a well-defined set of behaviors and attributes. Most published approaches describe conceptually similar definitions , although they adopt alternate terminologies [2, 3, 10]. There is a high degree of agreement on the desired structure of the end result; we differ in how to get to the end result. Many approaches recommend first searching for the tangible objects , notably seeking the nouns in a requirements specification and any applicable verbs and adjectives. With nouns as the objects, the message interface is determined from the verbs, and the logical properties are derived from the adjectives. Although this basic approach may work for small systems, it is our experience that it simply will not scale up. First, it assumes that a complete, …

Method and apparatus for indicating a change in status of an object and its disposition using animation

Abstract: A method characterized by the steps of: a) determining an action to be taken on an object on a computer screen which changes the status of the object; b) modifying the visual appearance of the object through animation to reflect the change in status; and c) automatically moving the modified object on the screen to indicate the disposition of the object. With a delete or "trashing" action, an object is crumpled on screen to indicate that the object has become trash, and the crumpled object is moved across the screen and into a trash can icon to indicate its final disposition. One embodiment of the present invention is a pen based computer system including a central processing unit, a display assembly showing at least one object, and a pointer for inputting information to the computer system. Additionally, the system can receive a change in status command for the object, modify the visual appearance of the object, automatically move the object, and execute the change in status command.

Recognition and Structure from one 2D Model View: Observations on Prototypes, Object Classes and Symmetries

Abstract: In this note we discuss how recognition can be achieved from a single 2D model view exploiting prior knowledge of an object''s structure (e.g. symmetry). We prove that for any bilaterally symmetric 3D object one non- accidental 2D model view is sufficient for recognition. Symmetries of higher order allow the recovery of structure from one 2D view. Linear transformations can be learned exactly from a small set of examples in the case of "linear object classes" and used to produce new views of an object from a single view.

Dynamic control of sliding by robot hands for regrasping

Abstract: The problem of dynamic control of a multifingered hand manipulating an object is considered, under the condition that some of the fingertips slide on the object surface. This work has many useful applications when considered in conjunction with work already done in the area of regrasping. In performing certain tasks with grasped objects, it is often necessary to change the contact locations of the fingers on the object. One method of achieving this is to break and remake the contacts; another method is to slide the fingertips on the object surface. This work provides a dynamic coordinated control scheme for a hand by which one can perform regrasping and reorientation of an object in the planar case. >

Method for protecting data in a computer system

Abstract: A data processing system include a plurality of data objects which are accessible by application programs through a system level interface. Each data object has an associated user access list. In addition, each object has at least one key indicating which applications can access that object. The key is preferably maintained in a protected storage area, accessible only by the low level system interface. Both the application identifier key and the user who invoked that application must match the identifier information in the data object for access to be allowed to that object. If an unauthorized user attempts access to the data object through the correct application, or an authorized user attempts access through an incorrect application, access to the data object will be denied by the low level interface.

User-modifiable popup menus for object oriented behavior

Abstract: A graphical user interface for a data processing system includes a method of generating a popup menu of actions allowed on an object represented in the graphical user interface. The method includes the steps of interrogating extended attributes for an object and each elder object to the object. Interrogation is for default actions and suppression markers. With each interrogation step the method adds actions linked to the object or to an elder object by another application and removes actions identified by suppression markers by another application from an interim list. After interrogation of the layers for modifications from other applications, the method provides for determining if any user defined actions and suppression markers are present for the object. If yes, the user defined actions are added to the interim list and actions matched by the suppression markers are removed from the interim list. A popup menu is then generated from the interim list.

Production of three-dimensional objects

Abstract: A method for producing a three-dimensional object having selected elements which are colored differently than other elements of the object comprising the steps of: (a) providing a film of a photohardenable composition containing a photoresponsive agent; (b) irradiating the film in a cross-sectional pattern of the object to be formed; (c) selectively irradiating one or more portions of the cross-sectional pattern corresponding to the selected elements which are desired to be colored differently with radiation which activates the photoresponsive agent, the photoresponsive agent thereby producing color in or removing color from the selected irradiated portions of the cross-sectional pattern; (d) repeating the steps a, b and c to form successive adjacent cross-sectional patterns of the object; and (e) integrating the cross-sectional patterns together to provide the object.

Access restriction facility method and apparatus

Abstract: An access control mechanism for granting, revoking, and denying authorization to computer system objects using a customer supplied set of verbs, parameters, attributes, and functions. The access control mechanism employs a processor for providing access controls to objects comprising subject memory, verb memory, object memory, definition memory, rule memory and an evaluator. The processor may be embodied as a microprocessor and memory, or a computer using software. The subject memory stores specified user attributes in a matrix having information for each user on each row, with user attributes in each field. The object memory stores object names, object attributes, and rules for defined verb names. The definition memory stores field definitions, external function declarations and strings. The rule memory stores rule names with their associated boolean expressions. The evaluator determines whether or not access to a specific object is allowed according to specified or default rules, user and object attributes, and definitions. While the term "Discretionary Access Control" is used throughout this document, the mechanism described herein can be used to implement discretionary, mandatory, and nonOdiscretionary (Clark-Wilson) security models.

Mounting bracket apparatus

Abstract: A mounting bracket apparatus for securing a relatively heavy item of equipment such as an electrical transformer to an upstanding object or structure such as a utility pole. The mounting bracket employs a plurality of elongated and symmetrically shaped object contact members that each contact the pole at spaced gripping locations to enhance the frictional contact force.

Interactive transaction processing system

Abstract: A distributed object-based transaction system provides a plurality of terminals (4) and/or host computers (2) on which objects, or named memory spaces, reside. The objects are controlled by methods which are located on each respective terminal or host on which an object resides, and the methods can be invoked by any of the terminals or host computers. Updating the objects is accomplished by invoking the relevant method on each of the nodes wherein the object resides. The distributed object-based transaction system is particularly useful in the implementation of an auction system for remotely situated bidders utilizing interactive television.

Towards an Algebraic Semantics for the Object Paradigm

Abstract: This paper surveys our current state of knowledge (and ignorance) on the use of hidden sorted algebra as a foundation for the object paradigm. Our main goal is to support equational reasoning about properties of concurrent systems of objects, because of its simple and efficient mechanisation. We show how equational specifications can describe objects, inheritance and modules; our treatment of the latter topic emphasises the importance of reuse, and the role of the so-called Satisfaction Condition. We then consider how to prove things about objects, how to unify the object and logic paradigms by using logical variables that range over objects, and how to connect objects into concurrent systems. We provide a universal characterisation of parallel connection, and more generally, of parallel connection with synchronisation, and show how the former construction gives a class manager that provides unique identifiers for its objects. The paper concludes with some topics for further research.

From volumes to views: an approach to 3-D object recognition

Abstract: We present an approach to the recovery and recognition of 3-D objects from a single 2-D image. The approach is motivated by the need for more powerful indexing primitives, and shifts the burden of recognition from the model-based verification of simple image features to the bottom-up recovery of complex volumetric primitives. Given a recognition domain consisting of a database of objects, we first select a set of object-centered 3-D volumetric modeling primitives that can be used to construct the objects. Next, using a CAD system, we generate the set of aspects of the primitives. Unlike typical aspect-based recognition systems that use aspects to model entire objects, we use aspects to model the parts from which the objects are constructed. Consequently, the number of aspects is fixed and independent of the size of the object database. To accommodate the matching of partial aspects due to primitive occlusion, we introduce a hierarchical aspect representation based on the projected surfaces of the primitives; a set of conditional probabilities captures the ambiguity of mappings between the levels of the hierarchy. From a region segmentation of the input image, we present a novel formulation of the primitive recovery problem based on grouping the regions into aspects. No domain dependent heuristics are used; we exploit only the probabilities inherent in the aspect hierarchy. Once the aspects are recovered, we use the aspect hierarchy to infer a set of volumetric primitives and their connectivity relations. Subgraphs of the resulting graph, in which nodes represent 3-D primitives and arcs represent primitive connections, are used as indices to the object database. The verification of object hypotheses consists of a topological verification of the recovered graph, rather than a geometrical verification of image features. A system has been built to demonstrate the approach, and it has been successfully applied to both synthetic and real imagery.

Manipulation And Active Sensing By Pushing Using Tactile Feedback

Abstract: We investigate manipulation and active sensing by a pushing control system using only tactile feedback. The equations of motion of a pushed object are derived using a model of the object's limit surface, and we design a control system to translate and orient objects. The effectiveness of the proposed controller is confirmed through simulation and experiments. Active sensing of the object's center of mass is described. I. INTRODUCTTON Pushing is a useful robotic capability for positioning and orienting parts. Several researchers have demonstrated the utility of pushing operations by planning open-loop pushing sequences to position and orient polygonal objects despite the presence of uncertainty in the initial state (l, 2, 3, 4, 5, 6, 71. These operations typically plan for a known object shape and center of mass (CM) and a flat pushing fence or specially designed pusher geomehy to exploit the mechanics of pushing. Others have proposed pushing control systems based on visual feedback (8,9). The pusher makes point contact with the object, and the position and orientation of the object is determined by a vision system. The goal is to push the object along a desired trajectory. Uncertainty in the frictional forces governing the object's motion is compensated for by the appropriate design of a feedback controller. The purpose of this work is to investigate the possibility of useful manipulation by a pushing control system using only tactile feedback. Try closing your eyes and controlling the motion of an object on a table by pushing it with a finger. This is the type of capability we would like to give a robot. In contrast to vision, tactile sensing requires very little data processing. The tactile sensor is mounted directly on the manipulator and the robot requires no peripheral sensors. The primary difficulty arises from the fact that tactile sensing can only give local contactinformation. Theconfigurationof theobjecthas three degrees-of-freedom: two position coordinates and an orientation. When the pusher is in contact with the object, these three degrees-of- freedom may be equivalently expressed by the location of the pushing contact, the contact point on the perimeter of the object, and the orientation of the object. The tactile sensor we use is capable of sensing the contact location and the object orientation at the contact, but not the contact point on the object. With vision, all three degrees- of-freedom are directly sensed. Despite this missing information, we demonstrate that simple manipulation is possible by pushing using only tactile feedback. Specifically, we implement a controller to translate the object and regulate its orientation.

Security mechanism for a computer system

Abstract: A computer system includes a plurality of programs and a plurality of accessible objects. Each program has an associated program identifier, and at least some of the objects have respective access control lists (ACL). Each ACL entry may comprise a program identifier key and an access permission indication. When a user attempts to access an object by way of a program, an entry in the ACL of the object is selected by matching the entry keys with at least the program identifier of the program, and access is granted or denied on the basis of the access permission indication in the selected entry.

Apparatus and method for determining the volume, form and weight of objects

Abstract: An apparatus and method for determining the volume, form and weight of fish or other objects is presented. A linescan camera records a top view of an object and at the same time records a profile view of the object reflected by a mirror located adjacent to the object. The mirror is positioned to reflect a view of the object which is perpendicular to the direct view of the camera and to the direction of motion of a conveyor belt along which the object moves. As the object moves along a conveyor belt through the field of view of the camera, a number of cross-sectional images are recorded and transmitted to a microprocessor. The microprocessor determines the maximum width of each cross-section from the direct image and the maximum thickness from each cross-section reflected image. Based upon the width and height of each cross-section and a form factor and estimated object density, the microprocessor calculates volume ane weight for each cross-section and adds the series of object cross-sections together to determine a volume and weight of the object.

Matchmaker for assisting and executing the providing and conversion of data between objects in a data processing system storing data in typed objects having different data formats

Abstract: An object based data processing system including an extensible set of object types and a corresponding set of "object managers" wherein each object manager is a program for operating with the data stored in a corresponding type of object. The object managers in general support at least a standard set of operations. Any program can effect performance of these standard operations on objects of any type by making an "invocation" request. In response to an invocation request, object management services (which are available to all object managers) identifies and invokes an object manager that is suitable for performing the requested operation on the specified type of data. A mechanism is provided for linking data from one object into another object. A object catalog includes both information about objects and about links between objects. Data interchange services are provided for communicating data between objects of different types, using a set of standard data interchange formats. A matchmaker facility permits two processes that are to cooperate in a data interchange operation identify each other and to identify data formats they have in common. A facility is provided for managing shared data "resources". Customized versions of resources can be created and co-exist with standard resources. A resource retrieval function determines whether a customized or a standard resource is to be returned in response to each request for a resource.