Scheduling Of Facilities Research Articles

The substantiation of the optimum conditions of carrying out field research on the gas-condensate of low permeability wells of Achimov deposits at the Urengoy oil and gas condensate field

The gas dynamic studies are targeting at study of structure production and reservoir fluid, also their dynamics during the development processes reservoir, phase state of gas-condensate mixture, physical-chemical properties of hydrocarbons. Research results on the gas-condensate are using for estimation of gas and condensate reserves, development program scheduling and field facilities construction project, as well as to monitor and control the operation of the field. Observance of terms are recommending in the course of research, such as longstanding stabilization of the production conditions, differential pressure drawdown, carry over fluid phase with a gas current, conditions of separating and sampling, will improve accuracy prognosis main aspects and increase the efficiency of reservoir development.

Integrating multicore awareness functions into distribution middleware for improving performance of distributed audio surveillance

This paper describes an approach to improve the performance of the distributed audio-processing functions for audio surveillance systems. In order to increase portability, current distributed audio-processing uses the default capacities offered by the underlying scheduling facilities of the operating system. In this approach, a set of capacities are added to the distribution software that enable the reduction of the distributed processing time of audio frames at the server side by adding functions that utilize the underlying hardware resources including exclusive core reservation. By loosing some generality in the design of the distribution software, it is possible to increase performance and provide better isolation to selected audio tasks in the presence of other competing software tasks. The approach is designed and implemented as well as analyzed on general purpose computers with a server-client architecture using serial scheduling of the audio tasks and parallelizing the digital signal processing computations. The proposed solution is implemented and analyzed showing benefits in performance and robustness over single threaded audio processing. The resulting system is significantly more robust in the presence of other competing software tasks (noise). These results directly yield the possibility to manage more concurrent audio streams at the server side.

ADVANCED SCHEDULER FOR COOPERATIVE EXECUTION OF THREADS ON MULTI-CORE SYSTEM

Three architectures of the cooperative thread scheduler in a multithreaded application that is executed on a multi-core system are considered. Architecture A0 is based on the synchronization and scheduling facilities, which are provided by the operating system. Architecture A1 introduces a new synchronization primitive and a single queue of the blocked threads in the scheduler, which reduces the interaction activity between the threads and operating system, and significantly speed up the processes of blocking and unblocking the threads. Architecture A2 replaces the single queue of blocked threads with dedicated queues, one for each of the synchronizing primitives, extends the number of internal states of the primitive, reduces the inter- dependence of the scheduling threads, and further significantly speeds up the processes of blocking and unblocking the threads. All scheduler architectures are implemented on Windows operating systems and based on the User Mode Scheduling. Important experimental results are obtained for multithreaded applications that implement two blocked parallel algorithms of solving the linear algebraic equation systems by the Gaussian elimination. The algorithms differ in the way of the data distribution among threads and by the thread synchronization models. The number of threads varied from 32 to 7936. Architecture A1 shows the acceleration of up to 8.65% and the architecture A2 shows the acceleration of up to 11.98% compared to A0 architecture for the blocked parallel algorithms computing the triangular form and performing the back substitution. On the back substitution stage of the algorithms, architecture A1 gives the acceleration of up to 125%, and architecture A2 gives the acceleration of up to 413% compared to architecture A0. The experiments clearly show that the proposed architectures, A1 and A2 outperform A0 depending on the number of thread blocking and unblocking operations, which happen during the execution of multi-threaded applications. The conducted computational experiments demonstrate the improvement of parameters of multithreaded applications on a heterogeneous multi-core system due the proposed advanced versions of the thread scheduler.

GITIRBio: A Semantic and Distributed Service Oriented-Architecture for Bioinformatics Pipeline.

The need to process large quantities of data generated from genomic sequencing has resulted in a difficult task for life scientists who are not familiar with the use of command-line operations or developments in high performance computing and parallelization. This knowledge gap, along with unfamiliarity with necessary processes, can hinder the execution of data processing tasks. Furthermore, many of the commonly used bioinformatics tools for the scientific community are presented as isolated, unrelated entities that do not provide an integrated, guided, and assisted interaction with the scheduling facilities of computational resources or distribution, processing and mapping with runtime analysis. This paper presents the first approximation of a Web Services platform-based architecture (GITIRBio) that acts as a distributed front-end system for autonomous and assisted processing of parallel bioinformatics pipelines that has been validated using multiple sequences. Additionally, this platform allows integration with semantic repositories of genes for search annotations. GITIRBio is available at: http://c-head.ucaldas.edu.co:8080/gitirbio.

GITIRBio: A Semantic and Distributed Service Oriented- Architecture for Bioinformatics Pipeline

Summary The need to process large quantities of data generated from genomic sequencing has resulted in a difficult task for life scientists who are not familiar with the use of command-line operations or developments in high performance computing and parallelization. This knowledge gap, along with unfamiliarity with necessary processes, can hinder the execution of data processing tasks. Furthermore, many of the commonly used bioinformatics tools for the scientific community are presented as isolated, unrelated entities that do not provide an integrated, guided, and assisted interaction with the scheduling facilities of computational resources or distribution, processing and mapping with runtime analysis. This paper presents the first approximation of a Web Services platform-based architecture (GITIRBio) that acts as a distributed front-end system for autonomous and assisted processing of parallel bioinformatics pipelines that has been validated using multiple sequences. Additionally, this platform allows integration with semantic repositories of genes for search annotations. GITIRBio is available at: http://c-head.ucaldas.edu.co:8080/gitirbio

Extending the information-theoretic measures of the dynamic complexity of manufacturing systems

This paper revisits and extends the structural and dynamic complexity measures of manufacturing systems, which are based on an information-theoretic interpretation of the amount of information that is needed to describe the state of a manufacturing system. In this paper, a generic manufacturing system is modelled as a set of interacting resources and queues. At any moment in time, the combined specific states of the resources and queues define the overall state of the manufacturing system. The main contribution of this paper is a set of dynamic complexity measures that quantify the rate at which information is generated by the facility, and which may be applied with or without reference to the facility's schedule. A worked example demonstrates the step-by-step calculations to obtain values of the complexity measures, and guidance is provided on how to obtain the data needed to carry out the calculations. The links between these complexity measures and the behaviour of a facility are identified and described.

Separation of circadian and wake duration-dependent modulation of EEG activation during wakefulness

The separate contribution of circadian rhythmicity and elapsed time awake on electroencephalographic (EEG) activity during wakefulness was assessed. Seven men lived in an environmental scheduling facility for 4 weeks and completed fourteen 42.85-h ‘days’, each consisting of an extended (28.57-h) wake episode and a 14.28-h sleep opportunity. The circadian rhythm of plasma melatonin desynchronized from the 42.85-h day. This allowed quantification of the separate contribution of circadian phase and elapsed time awake to variation in EEG power spectra (1–32 Hz). EEG activity during standardized behavioral conditions was markedly affected by both circadian phase and elapsed time awake in an EEG frequency- and derivation-specific manner. The nadir of the circadian rhythm in alpha (8–12 Hz) activity in both fronto-central and occipito-parietal derivations occurred during the biological night, close to the crest of the melatonin rhythm. The nadir of the circadian rhythm of theta (4.5–8 Hz) and beta (20–32 Hz) activity in the fronto-central derivation was located close to the onset of melatonin secretion, i.e. during the wake maintenance zone. As time awake progressed, delta frequency (1–4.5 Hz) and beta (20–32 Hz) activity rose monotonically in frontal derivations. The interaction between the circadian and wake-dependent increase in frontal delta was such that the intrusion of delta was minimal when sustained wakefulness coincided with the biological day, but pronounced during the biological night. Our data imply that the circadian pacemaker facilitates frontal EEG activation during the wake maintenance zone, by generating an arousal signal that prevents the intrusion of low-frequency EEG components, the propensity for which increases progressively during wakefulness.

Age-Related Increase in Awakenings: Impaired Consolidation of NonREM Sleep at All Circadian Phases

(1) To assess the circadian and sleep-dependent regulation of the frequency and duration of awakenings in young and older people; (2) to determine whether age-related deterioration of sleep consolidation is related to an increase in the frequency or duration of awakenings; (3) to determine whether pre-awakening sleep structure is preferentially enriched by REM sleep or nonREM sleep and (4) to determine whether sleep structure prior to awakenings is affected by age. Between age-group comparison of sleep consolidation and sleep structure preceding awakenings. Environmental Scheduling Facility, General Clinical Research Center. Eleven healthy young men (21-30 years) and 13 older healthy men (n=9) and women (n=4) (64-74 years). Forced desynchrony between the sleep-wake cycle and circadian rhythms by scheduling of the rest-activity cycle to 28-h for 21-25 cycles. Circadian and sleep-dependent regulation of the frequency and duration of awakenings and of sleep structure preceding awakenings were assessed in 482 sleep episodes (9h 20 min each). The circadian modulation of wakefulness within sleep episodes was primarily related to a variation in the duration of awakenings. In contrast, the age-related reduction of sleep consolidation was primarily related to an increase in the frequency of awakenings. Whereas in both young and older subjects pre-awakening sleep contained more REM sleep than overall sleep, this enrichment of REM sleep (i.e., the gating of wakefulness by REM sleep) was diminished in older people. In older people, preawakening sleep contained more nonREM sleep and stage two sleep in particular, than in young people. At all circadian phases, the age-related reduction of sleep consolidation is primarily related to a reduction in the consolidation of nonREM sleep.

A scheduling application for WDM optical networks

Optical networking using WDM technology has matured considerably, and commercial WDM network equipment and WDM network control and management prototypes have appeared. To use such a network efficiently, a scheduling facility and its enabling mechanisms have to be provided. This scheduling facility should be integrated to interoperate with the rest of the network control and management software such as connection manager or signaling daemon. We present a scheduling application to address this need. The architecture for the application and its key components are presented. Agent-related enabling mechanisms are introduced to monitor the optical signal quality and collect performance measurements. A resource broker is used to manage the communication and interoperability between agents and the application. An event service is developed to decouple the communication between the agents and the scheduling application, and to enable the communication among the agents themselves. The scheduling application consists of the quality of signal information and threshold objects, current network usage, history data module, scheduling module, and access to a performance database. To provide traffic control and high network resource utilization, the application is equipped with wavelength scheduling algorithms. An experimental study for the basic scheduling algorithms has been conducted over the MONET DC network.

Object-oriented real-time concurrency

The primary goal of a real-time system is predictability. Achieving this goal requires all levels of the system to work in concert to provide fixed worst-case execution-times. Un-fortunately, many real-time systems are overly restrictive, providing only ad-hoc scheduling facilities and basic concurrent functionality. Ad-hoc scheduling makes developing, verifying, and maintaining a real-time system extremely difficult and time consuming. Basic concurrent functionality forces programmers to develop complex concurrent programs without the aid of high-level concurrency features.Encouraging the use of sophisticated real-time theory and methodology, in conjunction with high-level concurrency features, requires flexibility and extensibility. Giving real-time programmers access to the underlying system data-structures makes it possible to interact with the system to incorporate new ideas and fine-tune specific applications. This paper explores this approach by examining its effect on a selection of crucial real-time issues: real-time monitors, timeouts, dynamic-priority scheduling and basic priority inheritance. The approach is implemented in μC++ .

Predictive resource management for meta-applications

This paper defines meta-applications as large, related collections of computational tasks, designed to achieve a specific overall result, running on a (possibly geographically) distributed, non-dedicated meta-computing platform. To carry out such applications in an industrial context, one requires resource management and job scheduling facilities (including capacity planning), to ensure that the application is feasible using the available resources, that each component job will be sent to an appropriate resource, and that everything will finish before the computing resources are needed for other purposes. This requirement has been addressed by the PAC in three major European collaborative projects: PROMENVIR, TOOLSHED and HPC-VAO, leading to the creation of job scheduling software, in which scheduling is brought together with performance modelling of applications and systems, to provide meta-applications management facilities. This software is described, focusing on the performance modelling approach which was needed to support it. Early results from this approach are discussed, raising some new issues in performance modelling and software deployment for meta-applications. An indication is given about ongoing work at the PAC designed to overcome current limitations and address these outstanding issues.

Customized Message Passing

Replacing traditional operating systems communication implementations with customized implementations increases the performance of parallel and distributed applications. This paper describes the design and implementation of customizable message passing systems. The customized message passing systems are generated using application-specific information such as the profile of an application's communication pattern. FFT, Simplex, and Cholesky are used as example parallel applications. The message passing system has also been customized for different types of distributed system services including a distributed scheduling facility. The customized message passing system likewise improves the performance of these facilities and enhances their scalability. As a practical concern, as there are a large number of possible optimizations, object-oriented frameworks are employed to organize the implementations and to facilitate the choice of optimizations.

APPC/MVS distributed application support

Advanced Program-to-Program Communication for Multiple Virtual Storage (APPC/MVS) is a major evolutionary change to MVS for applications that need to connect and communicate across the enterprise. APPC/MVS is an implementation of Systems Network Architecture (SNA) LU 6.2 session-defined protocol. This new MVS environment includes services to enhance the creation, execution, and management of MVS peer-to-peer and client/server applications. In addition to providing connectivity and communications services, APPC/MVS also has scheduling facilities for managing concurrent work originating from other systems in the enterprise network. The objective of this paper is to survey these facilities by examples of usage and by relationships to existing MVS services. Topics include various types of distributed models and approaches, design considerations, and characteristics that represent candidates for an APPC/MVS implementation. Relationships of the APPC/MVS environment with the Customer Information Control System/Enterprise Systems Architecture (CICS/ ESA™), Information Management System/ Enterprise Systems Architecture Transaction Manager (IMS/ESA™ TM), Time Sharing Option Extensions (TSO/E), and batch environments are included.

A system for computer music performance

A computer music performance system (CMPS) is a computer system connected to input devices (including musical keyboards or other instruments) and to graphic and audio output devices. A human performer generates input events using the input devices. The CMPS responds to these events by computing and performing sequences of output actions whose intended timing is determined algorithmically. Because of the need for accurate timing of output actions, the scheduling requirements of a CMPS differ from those of general-purpose or conventional real-time systems. This paper describes the scheduling facilities of FORMULA, a CMPS used by many musicians. In addition to providing accurate timing of output action sequences, FORMULA provides other basic functions useful in musical applications: (1) per-process virtual time systems with independent relationships to real time; (2) process grouping mechanisms and language-level control structures with time-related semantics, and (3) integrated scheduling of tasks (such as compiling and editing) whose real-time constraints are less stringent than those of output action computations.

APL-based, on-line examination scheduler

EXAMination SCHEDULER is an APL based system used by the Asian Institute of Technology, Bangkok, Thailand for final examination scheduling. The user need not have any programming background to operate the system. Internally the scheduling is done in three steps. In the first step a graph colouring algorithm is used to find the minimum number of disjoint courses; in the second step an optimization algorithm is used to minimise the number of students appearing for more than one exam per day; and finally a post scheduling facility is provided for the user to make any necessary changes within the schedule and to print reports.

ISIS—a knowledge‐based system for factory scheduling

Abstract: Analysis of the job shop scheduling domain has indicated that the crux of the scheduling problem is the determination and satisfaction of a large variety of constraints. Schedules are influenced by such diverse and conflicting factors as due date requirements, cost restrictions, production levels, machine capabilities and substitutability, alternative production processes, order characteristics, resource requirements, and resource availability. This paper describes ISIS, a scheduling system capable of incorporating all relevant constraints in the construction of job shop schedules. We examine both the representation of constraints within ISIS, and the manner in which these constraints are used in conducting a constraint‐directed search for an acceptable schedule. The important issues relating to the relaxation of constraints are addressed. Finally, the interactive scheduling facilities provided by ISIS are considered.