Showing papers on "Task (computing) published in 2006"

Autonomous shaping: knowledge transfer in reinforcement learning

Abstract: We introduce the use of learned shaping rewards in reinforcement learning tasks, where an agent uses prior experience on a sequence of tasks to learn a portable predictor that estimates intermediate rewards, resulting in accelerated learning in later tasks that are related but distinct. Such agents can be trained on a sequence of relatively easy tasks in order to develop a more informative measure of reward that can be transferred to improve performance on more difficult tasks without requiring a hand coded shaping function. We use a rod positioning task to show that this significantly improves performance even after a very brief training period.

Queueing Network-Model Human Processor (QN-MHP): A computational architecture for multitask performance in human-machine systems

Abstract: Queueing Network-Model Human Processor (QN-MHP) is a computational architecture that integrates two complementary approaches to cognitive modeling: the queueing network approach and the symbolic approach (exemplified by the MHP/GOMS family of models, ACT-R, EPIC, and SOAR). Queueing networks are particularly suited for modeling parallel activities and complex structures. Symbolic models have particular strength in generating a person's actions in specific task situations. By integrating the two approaches, QN-MHP offers an architecture for mathematical modeling and real-time generation of concurrent activities in a truly concurrent manner. QN-MHP expands the three discrete serial stages of MHP, of perceptual, cognitive, and motor processing, into three continuous-transmission subnetworks of servers, each performing distinct psychological functions specified with a GOMS-style language. Multitask performance emerges as the behavior of multiple streams of information flowing through a network, with no need to devise complex, task-specific procedures to either interleave production rules into a serial program (ACT-R), or for an executive process to interactively control task processes (EPIC). Using QN-MHP, a driver performance model was created and interfaced with a driving simulator to perform a vehicle steering, and a map reading task concurrently and in real time. The performance data of the model are similar to human subjects performing the same tasks.

System, method, and computer program product for media publishing request processing

Abstract: A system, method, and computer program product for publishing transcoded media content in response to publishing service requests from end users. A user request for media content, is processed intelligently, either by directing the processing of the request to one of a set of transcoding servers so as to effectively balance the load among the servers, or by directing the processing of the request to an appropriate alternative means for satisfying the request. Transcoding tasks can be prioritized. Moreover, the current load on any particular transcoding server can be monitored in conjunction with determination of the load to be created by a transcoding task, in order to facilitate server selection. Transcoding can be performed on-demand or in a batch mode. Alternatively, a request can be satisfied by distributing media content that has already been transcoded and is resident in cache memory in anticipation of such requests.

Reliable computing with a many-core processor

Abstract: According to embodiments of the disclosed subject matter, cores in a many-core processor may be periodically tested to obtain and/or refresh their dynamic profiles. The dynamic profile of a core may include information on its maximum operating frequency, power consumption, power leakage, functional correctness, and other parameters, as well as the trending information of these parameters. Once a dynamic profile has been created for each core, cores in a many-core processor may be grouped into different bins according to their characteristics. Based on dynamic profiles and the grouping information, the operating system ('OS') or other software may allocate a task to those cores that are most suitable for the task. The interconnect fabric in the many-core processor may be reconfigured to ensure a high level of connectivity among the selected cores. Additionally, cores may be re-allocated and/or re-balanced to a task in response to changes in the environment.

A method for multitask fMRI data fusion applied to schizophrenia.

Abstract: It is becoming common to collect data from multiple functional magnetic resonance imaging (fMRI) paradigms on a single individual. The data from these experiments are typically analyzed separately and sometimes directly subtracted from one another on a voxel-by-voxel basis. These comparative approaches, although useful, do not directly attempt to examine potential commonalities between tasks and between voxels. To remedy this we propose a method to extract maximally spatially independent maps for each task that are "coupled" together by a shared loading parameter. We first compute an activation map for each task and each individual as "features," which are then used to perform joint independent component analysis (jICA) on the group data. We demonstrate our approach on a data set derived from healthy controls and schizophrenia patients, each of which carried out an auditory oddball task and a Sternberg working memory task. Our analysis approach revealed two interesting findings in the data that were missed with traditional analyses. First, consistent with our hypotheses, schizophrenia patients demonstrate "decreased" connectivity in a joint network including portions of regions implicated in two prevalent models of schizophrenia. A second finding is that for the voxels identified by the jICA analysis, the correlation between the two tasks was significantly higher in patients than in controls. This finding suggests that schizophrenia patients activate "more similarly" for both tasks than do controls. A possible synthesis of both findings is that patients are activating less, but also activating with a less-unique set of regions for these very different tasks. Both of the findings described support the claim that examination of joint activation across multiple tasks can enable new questions to be posed about fMRI data. Our approach can also be applied to data using more than two tasks. It thus provides a way to integrate and probe brain networks using a variety of tasks and may increase our understanding of coordinated brain networks and the impact of pathology upon them.

Multi-dimensional computation distribution in a packet processing device having multiple processing architecture

Abstract: Flow-aware task distribution in network devices having multiple processor architectures. In one embodiment, the present invention can be used for high bandwidth network processing in an application and flow aware Quality of Service (QoS) network device. In some implementations, the present invention provides a task distribution architecture capable of flow state awareness and link level QoS control. In some implementations, the present invention can incorporate one or more processes, such as flow distributors and device distributors, that route packets for processing among different processing units on the basis flow correspondence and/or link or network path attributes. The flow and device distributors, in one implementation, allow for the separation and paralletization of packet processing functionality into flow-specific and link-specific processing units, allowing for a highly-scalable, flow-aware task distribution in a network device that processes network application traffic.

A multi-robot system for continuous area sweeping tasks

Abstract: As mobile robots become increasingly autonomous over extended periods of time, opportunities arise for their use on repetitive tasks. We define and implement behaviors for a class of such tasks that we call continuous area sweeping tasks. A continuous area sweeping task is one in which a group of robots must repeatedly visit all points in a fixed area, possibly with nonuniform frequency, as specified by a task-dependent cost function. Examples of problems that need continuous area sweeping are trash removal in a large building and routine surveillance. In our previous work we have introduced a single-robot approach to this problem. In this paper, we extend that approach to multi-robot scenarios. The focus of this paper is adaptive and decentralized task assignment in continuous area sweeping problems, with the aim of ensuring stability in environments with dynamic factors, such as robot malfunctions or the addition of new robots to the team. Our proposed negotiation-based approach is fully implemented and tested both in simulation and on physical robots

Multi-rule Multi-objective Simulated Annealing Algorithm for Straight and U Type Assembly Line Balancing Problems

Abstract: The task of balancing of assembly lines is of considerable industrial importance. It consists of assigning operations to workstations in a production line in such a way that (1) no assembly precedence constraint is violated, (2) no workstations in the line takes longer than a predefined cycle time to perform all tasks assigned to it, and (3) as few workstations as possible are needed to perform all the tasks in the set. This paper presents a new multiple objective simulated annealing (SA) algorithm for simple (line) and U type assembly line balancing problems with the aim of maximizing “smoothness index” and maximizing the “line performance” (or minimizing the number of workstations). The proposed algorithm makes use of task assignment rules in constructing feasible solutions. The proposed algorithm is tested and compared with literature test problems. The proposed algorithm found the optimal solutions for each problem in short computational times. A detailed performance analysis of the selected task assignment rules is also given in the paper.

System and method for managing healthcare work flow

Abstract: A system and method for managing tasks and workflow in a complex environment such as a healthcare unit are described. The architecture of the inventive system includes core components and peripheral components that interact with each primarily through an interfacing event framework application within the core system. In addition to the event framework, the core system comprises a collaborative task platform and an intelligence application. The peripheral components include input devices for users, a system applications server, an integration server, person and asset tracking tags, a database server, and a knowledge base. The system manages workflow through a task-based orientation, and making use of task-based process mapping. Tasks may be created, including unstructured tasks, tasks may further be monitored, shared, transferred, and completed. The process may be envisioned as circular feedback loop including task management, metrics tracking, and real time process feedback. The task is a unit of transaction and central to system-based calculations which can measure return on investment that may, for example, include shorter length of stay in an emergency room, a decrease in medical errors, and an increase in revenue.

Non-cooperative, semi-cooperative, and cooperative games-based grid resource allocation

Abstract: In this paper we consider, compare and analyze three game theoretical grid resource allocation mechanisms. Namely, 1) the non-cooperative sealed-bid method where tasks are auctioned off to the highest bidder, 2) the semi-cooperative n-round sealed-bid method in which each site delegate its work to others if it cannot perform the work itself, and 3) the cooperative method in which all of the sites deliberate with one another to execute all the tasks as efficiently as possible. To experimentally evaluate the above mentioned techniques, we perform extensive simulation studies that effectively encapsulate the task and machine heterogeneity. The tasks are assumed to be independent and bear multiple execution time deadlines. The simulation model is built around a hierarchical grid infrastructure where machines are abstracted into larger computing centers labeled "federations", each of which are responsible for managing their own resources independently. These federations are then linked together with a primary portal to which grid tasks would be submitted. To measure the effectiveness of these game theoretical techniques, the recorded performance is evaluated against a conventional baseline method in which tasks are randomly assigned to the sites without any task execution guarantee.

Multi-service request within a contact center

Abstract: A contact center that includes: (a) an input 200 operable to receive a contact; (b) a task expert module 232 to (i) identify a plurality of tasks 400 associated with the contact; (ii) group the tasks 400 into first and second task sets; and (iii) queue the first and second task sets at different positions in at least one queue 208 ; and (c) an agent and work item selector 220 to assign the first task set to a first agent for servicing while maintaining the second task set in the at least one queue 208.

Performance Analysis Based System Level Power Management

Abstract: A multiprocessor system-on-chip 102 with dynamic adaptive power management for execution of data-dependent applications comprises strategically placed performance counters to collect run-time performance requirements of tasks. A power manager 130 issues DVS 132, DFS 134, time-out 136, and other controls to the various system resources being monitored. As the tasks execute during run- time, the quality of the match between the task and the resource it was scheduled to is analyzed. More accurate power controls and schedules are then made available and stored in a performance requirements table. The power-management is therefore adaptive and dynamic. During a static analysis phase, applications and tasks that can be pre-characterized for their performance requirements are profiled and pre-loaded as initial starting points for correction during run-time.

Bounding Preemption Delay within Data Cache Reference Patterns for Real-Time Tasks

Abstract: Caches have become invaluable for higher-end architectures to hide, in part, the increasing gap between processor speed and memory access times. While the effect of caches on timing predictability of single real-time tasks has been the focus of much research, bounding the overhead of cache warm-ups after preemptions remains a challenging problem, particularly for data caches. In this paper, we bound the penalty of cache interference for real-time tasks by providing accurate predictions of the data cache behavior across preemptions. For every task, we derive data cache reference patterns for all scalar and non-scalar references. Partial timing of a task is performed up to a preemption point using these patterns. The effects of cache interference are then analyzed using a settheoretic approach, which identifies the number and location of additional misses due to preemption. A feedback mechanism provides the means to interact with the timing analyzer, which subsequently times another interval of a task bounded by the next preemption. Our experimental results demonstrate that it is sufficient to consider the n most expensive preemption points, where n is the maximum possible number of preemptions. Further, it is shown that such accurate modeling of data cache behavior in preemptive systems significantly improves the WCET predictions for a task. To the best of our knowledge, our work of bounding preemption delay for data caches is unprecedented.

Processor and information processing method

Abstract: A multiprocessor is provided that efficiently processes high priority processing. A mobile telephone 1 comprises a CPU 10 having therein an external interrupt control section 11 that causes a unit processor that is not executing a task or the unit processor executing the lowest priority task to execute an interrupt processing that was input. Thus, interrupt processing that occurred can be executed within the CPU 10 without, as far as possible, reducing the capacity to process tasks. Accordingly, interrupt processing can be efficiently processed within the CPU 10 as a multiprocessor.

Asymmetric multi-GPU processing

Abstract: A system for processing video data includes a host processor, a first media processing device coupled to a first buffer, the first media processing device configured to perform a first processing task on a frame of video data, and a second media processing device coupled to a second buffer, the second media processing device configured to perform a second processing task on the processed frame of video data The architecture allows the two devices to have asymmetric video processing capabilities Thus, the first device may advantageously perform a first task, such as decoding, while the second device performs a second task, such as post processing, according to the respective capabilities of each device, thereby increasing processing efficiency relative to prior art systems Further, one driver may be used for both devices, enabling applications to take advantage of the system's accelerated processing capabilities without requiring code changes

Processor Cluster Architecture and Associated Parallel Processing Methods

Abstract: A parallel processing architecture comprising a cluster of embedded processors that share a common code distribution bus. Pages or blocks of code are concurrently loaded into respective program memories of some or all of these processors (typically all processors assigned to a particular task) over the code distribution bus, and are executed in parallel by these processors. A task control processor determines when all of the processors assigned to a particular task have finished executing the current code page, and then loads a new code page (e.g., the next sequential code page within a task) into the program memories of these processors for execution. The processors within the cluster preferably share a common memory (1 per cluster) that is used to receive data inputs from, and to provide data outputs to, a higher level processor. Multiple interconnected clusters may be integrated within a common integrated circuit device.

Secure device sharing

Abstract: A device and method for placing the device in a locked state having an associated set of permitted tasks so as to permit the device owner to share the device with others but maintain security over aspects of the device. A task change request is evaluated to determine whether the requested task is permitted and, if so, the requested task is allowed; if not, then an authorization process is invoked to prompt the user to input authorization data. Upon verification of the authorization data, the device may be unlocked and the requested change implemented. The permitted tasks may designate specific applications, specific operations or functions within applications or at the operating system level, one or more currently open windows, and other levels of granularity.

Assignment of Dynamically Perceived Tasks by Token Passing in Multirobot Systems

Abstract: The problem of assigning tasks to a group of robots acting in a dynamic environment is a fundamental issue for a multirobot system (MRS) and several techniques have been studied to address this problem. Such techniques usually rely on the assumption that tasks to be assigned are inserted into the system in a coherent fashion. In this work we consider a scenario where tasks to be accomplished are perceived by the robots during mission execution. This issue has a significative impact on the task allocation process and, at the same time, makes it strictly dependent on perception capabilities of robots. More specifically, we present an asynchronous distributed mechanism based on Token Passing for allocating tasks in a team of robots. We tested and evaluated our approach by means of experiments both in a simulated environment and with real robots; our scenario comprises a set of robots that must cooperatively collect a set of objects scattered in the working environment. Each object collection task requires the cooperation of two robots. The experiments in the simulation environment allowed us to extract quantitative data from several missions and in different operative conditions and to characterize in a statistical way the results of our approach, especially when the team size increases

Workflow scheduling system

Abstract: A workflow scheduling system arranged to provide a workflow to a user who has requested work to be implemented comprises means to generate a workflow comprising an a set of actions and a logical dependency between the actions; means to allocate a resource capacity to each action; and means to assign of one or more of said resources forming the resource capacity to a task comprising one or more of said actions. The system is arranged to enable a user to add one or more constraints dynamically to the workflow scheduling system without the need for the workflow scheduler to be recompiled to apply a constraint to the resources allocated to one or more tasks.

Processor task migration over a network in a multi-processor system

Abstract: Methods and apparatus for migrating and distributing processor tasks on a plurality of multi-processing systems distributed over a network. The multi-processing system includes at least one broadband entity, each broadband entity including a plurality of processing units and synergistic processing units, as well as a shared memory. Tasks from one broadband entity are bundled, migrated and processed remotely on other broadband entities to efficiently use processing resources, and then returned to the migrating broadband entity for completion or continued processing.

Device and method for controlling robot

Abstract: A robot controller making a robot execute tasks including several work units in a parallel manner for several workpieces, in accordance with several operation programs for individually commanding the work units. The robot controller includes an information collecting section collecting state information showing, in real time, a state of an environment of the robot; a program selecting section selecting a first executable program satisfying a task starting condition, from operation programs ready to be executed for workpieces, based on the state information; a processing section processing, for execution, the first executable program; and a program-completion judging section judging whether the processing section has completed a processing of the first executable program. The program selecting section selects, based on the state information, a second executable program satisfying the task starting condition, from the operation programs ready to be executed, so as to satisfy a judgment of the program-completion judging section.

Method and system for validating tasks

Abstract: A computer-implemented method and system for validating a task of a plurality of tasks of a project. A computing application executes routines to automatically identify errors associated with one or more tasks. The routines generate exception reports that facilitate correction of the errors via user-determined selections of actions or via corrective actions automatically displayed by the computing application. The error identification facilitates validation of project elements including milestones, dependencies and deliverables, key work products, tasks in a work breakdown structure (WBS), predecessors and successors in the WBS, resources, work and labor rates, links between project plans, and an update of a project. Further, the error identification facilitates an analysis of schedule conflicts between give and get tasks.

Event-Based Activity Tracking in Work Environments

Abstract: Wearable computers aim to empower people by providing relevant information at appropriate time. This context-based information delivery helps to perform intricate, tedious or critical tasks and improves productivity, decreases error rates, and thus results in a reduction of labor cost. To evaluate the usability of wearable computing in a work environment, we have chosen a car production scenario in which new employees are trained for mechanical assembly tasks. In this paper we describe the implementation of an activity tracking system that allows to detect the individual steps of assembling a front lamp into a car body. Our approach is to break down these steps of the assembly task into smaller units, so called discrete events. Body-worn and environmental sensors are employed to create these events which trigger transitions in a Finite State Machine (FSM). The FSM states represent user activities which correspond to the assembly steps.

Exact Solutions to Task Allocation Problems

Abstract: The task allocation problem (TAP) is one where a number of tasks or modules need to be assigned to a set of processors or machines at minimum overall cost. The overall cost includes the communication cost between tasks that are assigned to different processors and other costs such as the assignment cost and the fixed cost of using processors. Processors may have limited or unlimited capacities to perform tasks. Task allocation has been applied to the design of distributed computing systems and also in auto-manufacturing contexts. We present several integer programs and a column generation formulation for the uncapacitated and the capacitated TAP. Computational experiments are carried out to demonstrate computational capabilities of integer programming and the column generation formulations for the uncapacitated TAP (UTAP). Excellent results are obtained for the column generation formulation. We also report some computational experience for the capacitated TAP (CTAP).

Portability and applicability of virtual fixtures across medical and manufacturing tasks

Abstract: Virtual fixtures are virtual constraints that enhance human performance in motion tasks. They can either confine and/or guide a user's motion. In this paper, we use a commercially available motion platform to explore the portability and applicability of virtual fixtures and document how people interact with them. Two micromanipulation tasks are analyzed and the effects of similarly designed virtual fixtures are discussed. One task simulates a medical task, retinal vein cannulation, and the other simulates a manufacturing task, fine leads soldering. Preliminary experimental results show that the virtual fixtures increase the accuracy of both medical and manufacturing tasks, lending support to its portability and applicability across unrelated tasks

Task Partitioning with Replication upon Heterogeneous Multiprocessor Systems

Abstract: The heterogeneous multiprocessor task partitioning with replication problem involves determining a mapping of recurring tasks upon a set consisting of different processing units in such a way that all tasks meet their timing constraints and no two replicas of the same task are assigned to the same processing unit. The replication requirement improves the resilience of the real-time system to a finite number of processor failures. This problem is NP-hard in the strong sense. We develop a Fully Polynomial-Time Approximation Scheme (FPTAS) for this problem.

Dynamic generation of tasks in resource constrained devices

Abstract: A method and system for dynamic generation of tasks in resource constrained devices involves identifying tasks that can be performed by devices in a resource constrained network, wherein the tasks represent activities that can be performed by the devices. Tasks are generated using the capabilities of devices as each device is discovered in the network. A task uses one or more functionalities of one or more devices. Task generation specifically takes into account the limited memory and processing power which a typical home device possesses, and the tasks are generated dynamically.

Task construction for model-based design of embedded control software

Abstract: Constructing runtime tasks, or operating system-level processes/threads, from the components of software design models is crucial to the model-based development of embedded control software. A better method should explore more design choices and reduce the overheads of the runtime system to meet the timing and resource constraints of embedded control software. This paper presents a novel, two-step method for systematic and automatic construction of runtime tasks from software design models. It uses graph transformation to construct a task set meeting system-level end-to-end (e2e) timing constraints. Its first step decomposes the system-level e2e timing constraints into the components' timing constraints, which form a necessary condition for any valid and feasible schedule. The second step iteratively merges the components into tasks and sequences their executions. A thus-constructed task set is proven to meet both intercomponent precedence and system-level e2e timing constraints and to minimize runtime overheads by minimizing the total number of resultant tasks. Our evaluation results based on randomly generated software models have shown that the proposed method outperforms commonly used methods and is also scalable.