Scheduling Theory Research Articles

High-Order Sliding Mode Control for Networked Control System with Dynamic Noncooperative Game Scheduling

Specific to the NCSs where sensor signals can be processed centrally, a collaborative design scheme of dynamic game scheduling and advanced control theory was proposed in the present study. Firstly, by using the Jordan standard state space equation of the research object, the three elements of state noncooperative game were built, and the existence and uniqueness of Nash equilibrium solution were verified. In addition, the iterative equation of the scheduling matrix was derived by complying with the designed utility function. Secondly, refer to the number of restricted states the order of sliding mode was determined. And based on it, the corresponding sliding surface was designed. Subsequently, the quadratic optimization theory was adopted to regulate the control value following the implementation of the scheduling strategy to ensure that the control quality was further enhanced in the limited network service. Lastly, a TrueTime simulation example is established to verify the effectiveness of the proposed scheme.

Energy-efficient scheduling: classification, bounds, and algorithms

The problem of attaining energy efficiency in distributed systems is of importance, but a general, non-domain-specific theory of energy-minimal scheduling is far from developed. In this paper, we classify the problems of energy-minimal scheduling and present theoretical foundations of the same. We derive results concerning energy-minimal scheduling of independent jobs in a distributed system with functionally similar machines with different working and idle power ratings. The machines considered in our system can have identical as well as different speeds. If the jobs can be divided into arbitrary parts, we show that the minimum-energy schedule can be generated in linear time and give exact scheduling algorithms. For the cases where jobs are non-divisible, we prove that the scheduling problems are NP-hard and also give approximation algorithms for the same along with their bounds.

The gap and its reduction between theory and reality of construction schedules in the UAE

The construction industry is constantly changing due to market conditions and increased competition. The competition, in particular, has resulted in the need in better schedule performance for construction projects. Construction schedules are fundamental and challenging activities in the execution as well as management of construction projects. Besides, scheduling is an essential function of the project management since it provides a roadmap illustrating all the activities, milestones, and deliverables within a project to prevent any delays during the project’s commission as well as handover. In project management, delays have an adverse effect on the construction lifecycle and mainly arise from poor planning as well as forecasting techniques, insufficient knowledge on scheduling techniques, and inadequate or inefficient communication processes or technologies. The aim of this study is to identify the gap between scheduling theory and scheduling practices in reality of construction schedules in the UAE and its reduction methods in the practice. It will review existing literature to link schedule theory and good practices to illustrate the relationship between schedule problems and usage to recommend ways of improvements. A concise methodology stating the proposed research design and instrument is also provided.

Partitioning Stateful Data Stream Applications in Dynamic Edge Cloud Environments

Computation partitioning is an important technique to improve the application performance by selectively offloading some computations from the mobile devices to the nearby edge cloud. In a dynamic environment in which the network bandwidth to the edge cloud may change frequently, the partitioning of the computation needs to be updated accordingly. The frequent updating of partitioning leads to high state migration cost between the mobile side and edge cloud. However, existing works don’t take the state migration overhead into consideration. Consequently, the partitioning decisions may cause significant network congestion and increase overall completion time tremendously. In this article, with considering the state migration overhead, we propose a set of novel algorithms to update the partitioning based on the changing network bandwidth. To the best of our knowledge, this is the first work on computation partitioning for stateful data stream applications in dynamic environments. The algorithms aim to alleviate the network congestion and minimize the make-span through selectively migrating state in dynamic edge cloud environments. Extensive simulations show our solution not only could selectively migrate state but also outperforms other classical benchmark algorithms in terms of make-span. The proposed model and algorithms will enrich the scheduling theory for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">stateful</i> tasks, which has not been explored before.

Q-CSF: Quantum-Aware Compositional Scheduling Framework for Hierarchical Real-Time Systems

Component-based design has received considerable attention owing to its advantages in terms of security and safety when developing modern embedded systems. To effectively allocate computing resources to components in these systems, real-time component-based scheduling theory has been studied from various perspectives. The main advantage of component-based scheduling theory is that it guarantees the schedulability of an independent component and composability of multiple components. However, the existing component scheduling theory cannot be directly applied to real hardware platform due to an impractical assumption that resource allocation must be conducted across the continuum of real numbers, whereas actual operating systems (or virtualization systems) allocate resources in units of scheduling time quantum. In this study, we proposed a new efficient resource allocation and supply mechanism for quantumized hardware platforms while using real-number-based component interface. In simulation results with randomly-generated workloads, our approach reduced the overhead of existing approaches by up to 97.1% in an individual component. In composition of multiple components, our approach has up to 0.41 better acceptance ratio than existing approaches.

Production scheduling problem of automobile mixed model assembly line

Nowadays, the mode of production has changed from mass production to multi variety and small batch production, and mixed model assembly line has emerged. Mixed model assembly is widely used in automobile enterprises. This paper summarizes the theory and method of automobile mixed model assembly line scheduling, analyzes its characteristics and difficulties, summarizes the related optimization objectives, and introduces the related algorithms, so as to make the scheduling problem of mixed model assembly line more clear.

Workflow Scheduling Based on Mobile Cloud Computing Machine Learning

In recent years, cloud workflow task scheduling has always been an important research topic in the business world. Cloud workflow task scheduling means that the workflow tasks submitted by users are allocated to appropriate computing resources for execution, and the corresponding fees are paid in real time according to the usage of resources. For most ordinary users, they are mainly concerned with the two service quality indicators of workflow task completion time and execution cost. Therefore, how cloud service providers design a scheduling algorithm to optimize task completion time and cost is a very important issue. This paper proposes research on workflow scheduling based on mobile cloud computing machine learning, and this paper conducts research by using literature research methods, experimental analysis methods, and other methods. This article has deeply studied mobile cloud computing, machine learning, task scheduling, and other related theories, and a workflow task scheduling system model was established based on mobile cloud computing machine learning from different algorithms used in processing task completion time, task service costs, task scheduling, and resource usage The situation and the influence of different tasks on the experimental results are analyzed in many aspects. The algorithm in this paper speeds up the scheduling time by about 7% under a different number of tasks and reduces the scheduling cost by about 2% compared with other algorithms. The algorithm in this paper has been obviously optimized in time scheduling and task scheduling.

ВПЛИВ МАРКЕТИНГОВОЇ ПОЛІТИКИ НА ОПТИМІЗАЦІЮ ПЛАНУВАННЯ РОБОТИ ПОСТАЧАЛЬНИЦЬКОЇ ФІРМИ В ЛАНЦЮЗІ ПОСТАВОК

As is known, the problem of determining economically justified volumes of supplies in the theory and practice of logistics management plays a key role in ensuring the efficient operation of both individual enterprises and supply chains. Logistics, which is the science of effective management of material, information and financial flows in the field of production and circulation, is closely related to such sections of operations research as mathematical programming, inventory management theory, schedule theory, queuing theory and more. Many tasks of logistics are directly related to the optimal management of stocks of raw materials, semi-finished and finished products, as well as the construction of an optimal schedule for delivery of finished products to points of consumption with the participation of trunk transport. Thus, since the issues of optimal inventory management are of paramount importance in logistics, it means the importance of inventory theory in the design and operation of various logistics systems. The article is devoted to substantiation of expediency and efficiency of additional costs of a supply firm for advertisement with the aim to its profit increasing on the fixed planning horizon under supposition that the expected demand at point of destination may be controlled by firm. For this problem solving the modification of classical Wilson’s model from inventory control theory is used to maximize the total profit of firm for sailing the good, taking into account ordering, delivery and storage of good costs on the planning horizon and additional cost for advertisement of good. It is assumed that buying/sailing prices of good are known, as well as daily expenses for storage of good at warehouse. It is supposed also that demand for the good is an increasing function of advertisement costs. The case of linear dependence of demand on advertisement cost is studied in details. For this particular case the optimal value of ordering party of good and optimal value of cost for advertisement are found in evident form. It is shown also that above optimization model may be generalized for the case of several kinds of good. Restrictions on the capacity of the warehouse for storage of goods and restrictions on the financial resources available to the company allocated for advertising activities are taken into account. A convex optimization problem is obtained, which can be solved numerically using the Excel application package.

Developing a System to Support Banks in Making Investment Decisions when Organizing Project Financing

The article deals with the development of an information system providing support for making investment decisions by Ziraat Bank in organizing project financing of innovative projects implemented within the machinebuilding cluster of the Republic of Tatarstan and its affiliated entities in the Russian Federation. A set of requirements for such a system was formulated and an appropriate mathematical model developed. The software implementation of the mathematical model was carried out in the Ziraat Bank's investment decision support system. An algorithm for system development was proposed, the practical implementation of which was performed using the theory of oriented graphs along with the schedule theory.

50 anos de estudos sobre o agendamento – Caminhos de uma teoria dos media

Com o presente número da revista Mediapolis pretendemos marcar os 50 anos decorridos sobre o seminal estudo de Chapel Hill, que deu origem a uma das áreas mais consistentes de estudos das Ciências da Comunicação, realizados sobre os media: a teoria do agenda setting ou do agendamento. O início desta história teve origem quando Maxwel McCombs e Donald Shaw, então dois jovens investigadores, decidiram analisar como, a propósito das eleições presidenciais norte- americanas de 1968, que opuseram Hubert Humphrey e Richard Nixon, os media poderiam, de algum modo, influenciar a opinião pública. Para o efeito, realizaram um estudo tendo por base 100 eleitores indecisos, residentes em Chapel Hill, na Carolina do Norte, acabando por encontrar um coeficiente muito forte de correlação entre a agenda mediática e a agenda dos eleitores. A agenda setting, numa fase inicial, começou por afirmar que pessoas acabam por conhecer determinados assuntos pelo efeito da seleção realizada pelos media que, deste modo, transforma temas, pessoas e acontecimentos em matéria privilegiada do debate público, marcando um paralelismo entre a agenda dos media e a agenda da opinião pública.

Expressing survivability considerations in mixed-criticality scheduling theory

Abstract Mixed-criticality scheduling theory (MCSh) was developed to allow for more resource-efficient implementation of systems comprising different components that need to have their correctness validated at different levels of assurance. MCSh is primarily concerned with the pre-runtime verification of such systems; hence many mixed-criticality scheduling algorithms tend to exhibit poor survivability characteristics during run-time. (e.g., MCSh allows for less-important (“ lo -criticality”) workloads to be completely discarded in the event that run-time behavior is not compliant with the assumptions under which the correctness of the lo -criticality workload should be verified.) We propose extensions to MCSh to make it cognizant of survivability considerations, by defining quantitative metrics for the robustness and resilience of mixed-criticality scheduling algorithms. Such metrics allow us to make quantitative assertions regarding the survivability characteristics of mixed-criticality scheduling algorithms, and to compare different algorithms from the perspective of their survivability.

Utilization-Tensity Bound for Real-Time DAG Tasks under Global EDF Scheduling

Utilization bound is a well-known concept in real-time scheduling theory for sequential periodic tasks, which can be used both for quantifying the performance of scheduling algorithms and as efficient schedulability tests. However, the schedulability of parallel real time task graphs depends on not only utilization, but also another parameter tensity , the ratio between the longest path length and period. In this paper, we use utilization-tensity bounds to better characterize the schedulability of parallel real-time tasks. In particular, we derive utilization-tensity bounds for parallel DAG tasks under global EDF scheduling, which facilitate significantly more precise schedulability analysis than the state-of-the-art analysis techniques based on capacity augmentation bound and response time analysis. Moreover, we apply the above results to the federated scheduling paradigm to improve the system schedulability by choosing proper scheduling strategies for tasks with different workload and structure features.

Tramp Ship Routing and Scheduling with Speed Optimization Considering Carbon Emissions

The International Maritime Organization (IMO) proposed to reduce the total CO2 emissions of the maritime sector by 50% by 2050, and strive to gradually achieve the zero-carbon target. Therefore, shipping companies need to consider environmental impacts while pursuing benefits. In view of the tramp ship scheduling with speed optimization problem, considering carbon emissions, the configuration of owner ships and charter ships, and the impact of sailing speed on ship scheduling with the target of minimizing the total costs of shipping companies, multi-type tramp ship scheduling and speed optimization considering carbon emissions is established. A genetic simulated annealing algorithm based on a variable neighborhood search is proposed to solve the problem. Firstly, the ship type is matched with the cargo. Then the route is generated according to the time constraint, and finally, the neighborhood search strategy is adopted to improve the solution quality. The effectiveness of the proposed model and algorithm is verified by an example, which also confirms that ship scheduling and sailing speed joint optimization can reduce costs and carbon emissions. Research results can not only deepen the study of the theory of tramp scheduling but also to effectively solve the tramp shipping schedule considering carbon emissions problems faced by companies to provide theoretical guidance.

Discursos midiáticos sobre questões ambientais: um estudo na perspectiva das representações sociais

Este artigo parte do pressuposto de que enunciados só adquirem sentido nos contextos em que são produzidos, apresentando significações diferenciadas, a partir de quem, como e para quem são pronunciados, e em que suportes são veiculados. Considera-se, então, que as mídias podem contribuir significativamente para a aquisição de hábitos e costumes de leitores, além de apresentarem uma perspectiva ideológica de quem produz, com possíveis contrapontos às ideologias de quem os recebe. Nesse contexto, faz-se necessário destacar a importância do gênero textual propaganda que, ao divulgar um produto, veicula uma representação do produtor, e busca alcançar a adesão não apenas de consumidores diretos, mas também de parcelas da população. Posto isto, o presente trabalho tem como objeto de discussão propagandas da empresa Monsanto - empresa de produção agrícola em escala mundial, bem como propagandas de ONGs, cujo objetivo é esclarecer à população sobre a questão da soberania alimentar. A estrutura do artigo fundamenta-se em uma discussão inicial acerca de concepções de educação ambiental, soberania alimentar, agroecologia e representações sociais, buscando identificar, nos textos escolhidos, as concepções que os permeiam, bem como os ‘lugares’ sociais que buscam ocupar aqueles que os produzem. As discussões valem-se de subsídios explicitados pela Teoria das Representações Sociais, pela Análise do Discurso e pela Teoria Sociointeracionista da linguagem. Dessa maneira, foram analisados um total de quatro textos, sendo dois da Monsanto e dois de ONGs de diferentes países. O objetivo é apresentar contrapontos e relações entre os discursos, observando como esses podem se constituir ou se valer de representações sociais já constituídas para alcançar a aderência do consumidor. Contextualizam-se as mídias a partir de suas condições de produção, determinando o público-alvo de seus discursos e ações, retratadas nas propagandas. A perspectiva teórica e metodológica considera, além das teorias mencionadas, a Teoria do Agendamento. As conclusões iniciais que se podem inferir relacionam-se à percepção da mídia como produtora de um tratamento da informação refratando informações que podem contribuir para a construção/consolidação de representações sociais e a existência de uma dicotomia, propagada pela mídia.

Approximate Algorithm for Solving the General Problem of Scheduling Theory With High Accuracy

An approximate iterative algorithm is described, allowing the solving of general problems in the theory of schedules. The theoretical and experimental characteristic of the new algorithm are given, as well as ways of finding out its variable indicators by using parallelization computing and the implementation of a parallel version of the algorithm microprocessor. In this way, the authors have described a practical approximate algorithm for time, to solve the general problem of scheduling theory with an average error of 8% less.

The dynamic programming algorithm for management of real-time aircraft assignments

The schedule is the basis of any airline. In this paper, we provide one of the problems of schedule theory. This problem of optimal management of flight schedule is to minimize flight departure delays and to improve flight on-time performance. This paper provides a conceptual and mathematical formulation of optimizing an operating flight schedule problem. The problem solution is to manage the assignments of specific air-crafts on flights considering the operational information about the implementation of the planned flight schedule. This problem is NP-hard and can not be solved exactly for any real dimensions. We propose the parametric effective algorithm for its approximate solution and provide the statistical data for testing.

Partial Offloading Scheduling and Power Allocation for Mobile Edge Computing Systems

Mobile edge computing (MEC) is a promising technique to enhance computation capacity at the edge of mobile networks. The joint problem of partial offloading decision, offloading scheduling, and resource allocation for MEC systems is a challenging issue. In this paper, we investigate the joint problem of partial offloading scheduling and resource allocation for MEC systems with multiple independent tasks. A partial offloading scheduling and power allocation (POSP) problem in single-user MEC systems is formulated. The goal is to minimize the weighted sum of the execution delay and energy consumption while guaranteeing the transmission power constraint of the tasks. The execution delay of tasks running at both MEC and mobile device is considered. The energy consumption of both the task computing and task data transmission is considered as well. The formulated problem is a nonconvex mixed-integer optimization problem. In order to solve the formulated problem, we propose a two-level alternation method framework based on Lagrangian dual decomposition. The task offloading decision and offloading scheduling problem, given the allocated transmission power, is solved in the upper level using flow shop scheduling theory or greedy strategy, and the suboptimal power allocation with the partial offloading decision is obtained in the lower level using convex optimization techniques. We propose iterative algorithms for the joint problem of POSP. Numerical results demonstrate that the proposed algorithms achieve near-optimal delay performance with a large energy consumption reduction.

Формування узгодженого графіка руху для мультимодальних пасажирських перевезень за участю залізничного транспорту

The purpose of the work is to determine the conditions that must be created for the formation of efficient rail passenger traffic with the bus vehicles through the application of an agreed timetable of traffic (multimodal passenger transport). Analyzed the conditions are necessary for the formation of rail-bus passenger traffic according to a single timetable. According to the regulatory framework it has been established that they can be attributed to multimodal passenger transportation. Structurally-logical schemes of passenger traffic movement on transport interchange hubs during transmissions with the railway transport have been created. The technology of the transport interchange hub's work is formalized as a set of systems of Kolmogorov differential equations. The agreed timetable of vehicles provides for a unified technology for the work of different carriers and modes of transport. Thus, the formation of elements of the agreed timetable begins with: duration of transplantation in the hub’s taking into account the type of comfortable transplantation and the coordination of the parking from the technological point of view; the backup technological time is required to restore the integrated timetable in case of vehicle lag. The mathematical model of the agreed timetable of movement the passenger vehicles is proposed. The problem is proposed to be solved with the help of the theory of schedules as a task of minimizing the target function of a weighted number of belated requirements. The stage and efficiency of introduction of multimodal transportations of passengers in the conditions of the transport-transfer hub of the city ofDniprois determined.

Multiprocessor Scheduling meets the Industrial Wireless

This survey covers schedulability analysis approaches that have been recently proposed for multi-hop and multi-channel wireless sensor and actuator networks in the industrial control process domain. It reviews results with a focus on WirelessHART-like networks. The paper address the mapping of multi-channel transmission scheduling to multiprocessor scheduling theory, and recognize it as the key aspect of the research direction covered by this survey. It also provides a taxonomy of the existing approaches concerning this direction, and discuss its main features and evolution. The survey identifies open issues, key research challenges, and future directions.

MATHEMATICAL AND LOGICAL MODEL OF AIRCRAFT TIMETABLES

The article analyses the methods of forming the aircraft flight schedule based on the classical theory of schedules as a theory of multi-stage systems. It is shown that the timetable is a system without interruptions, since each specific flight at a certain point in time is carried out by only one aircraft. In accordance with the theory of schedules, the optimal distribution of a discrete finite set of requirements serviced by deterministic systems with one or more devices is analysed under various assumptions about the nature of their maintenance. It is shown that the weakest assumption regarding the abstract operator, which translates many requirements into many agreed and executed plans, is the monotonic and unimodal behaviour of the corresponding functional of the generated plans. The possibilities of applying the theory of multi-stage systems to create the optimal schedule for medium or large airlines are investigated. The basic requirements for constructing a schedule are advanced. Mathematical models of the schedule are constructed taking into account the basic data of the current movement of aircraft in the area of ​​the airport or air hub. It has been established that if the base airports change their purpose and act as terminal arrival airports, the corresponding matrix elements are inversely symmetric, and with a rarefied spatial distribution of airports, the matrix can tend to diagonally dominant. A comparative analysis of scheduling algorithms is performed (based on queuing models, based on lists with the distribution of flights over time, etc.). The most suitable indicators of the effectiveness of the formation of the optimal schedule and system of priorities were selected and justified, taking into account the advantages of the arrival and departure times of passenger flights. An expression is derived for the resulting functional schedule efficiency, with which you can get quantitative comparative assessments of the quality of the schedule.