Load Scheduling Research Articles

Joint scheduling optimization model for yard cranes and AGVs considering running routes

The escalation in global consumer demand has prompted the continual expansion of container throughput, which drives container terminals to bolster their production capacities. Globally, ports worldwide have been adopting automated equipment and embracing digital operational environments to reinforce their logistics system efficiency and curtail transportation costs. Enhancement of the efficiency of container transportation at automated terminals depends on terminal loading and unloading operations. The efficiency of these operations directly hinges on the automated mechanical equipment deployed at terminals. Consequently, optimization of resource allocation and production scheduling of loading and unloading equipment at terminals has become an essential and effective approach. In this regard, automated yard cranes, which are responsible for rear-end handling, and automated guided vehicles (AGVs), which transport containers between the yard and the terminal quay, have been proven indispensable. This paper principally delves into the scheduling optimization of mechanical equipment in automated container terminal yards, with a unique focus on the coordinated scheduling optimization of yard cranes and AGVs while also accounting for AGV path planning. This research centers on the automated container terminal yard system and the challenge in yard crane scheduling. This work also establishes a grid-based terminal network model and validates the model and algorithm using practical examples. Optimal solutions are obtained for the joint scheduling of yard cranes and AGVs, accompanied by strategies on rational AGV path selection. The findings provide valuable references and theoretical underpinnings for operational scheduling and enhancement of the efficiency in container transport in automated container terminal yards. Furthermore, these results facilitate the overall improvement of production efficiency at automated terminals and the reduction of operational costs, thus carrying theoretical and practical significance.

Operational Scheduling of Household Appliances by Using Triple-Objective Optimization Algorithm Integrated with Multi-Criteria Decision Making

Load scheduling is a key factor in demand side management (DSM), which manages available generation capacity with regard to the required demand. In this paper, a triple-objective load scheduling optimization problem (LSOP) is formulated for achieving optimal cost and peak demand as well as minimum customer inconvenience. A Henry gas solubility optimization (HGSO) algorithm that is based on multi-objective is used for solving LSOP. The proposed HGSO offers a set of compromise solutions that represent the tradeoff between the three objectives of the formulated problem. A set of all compromise solutions from the dominant Pareto front is achieved first, and then ranked by using MCDM so as to optimally sort these solutions. An entropy weighting method (EWM) is then used for computing the weights of various criteria that dominate the LSOP and is provided as a technique for ordering preferences by similarity to achieve the ideal solution (TOPSIS) so as to rank the sorted solutions. Two types of end-users are considered so as to show the effectiveness of the proposed LSOP: non-cooperative and cooperative users. The results of the proposed load scheduling method show the significance of the proposed method for both the cooperative and non-cooperative end-users. The proposed method achieves a cost of energy of R50.62 as a total cost of energy consumed by four non-cooperative end-users. The cost of energy for the cooperative end-users is found to be R47.39. Thus, saving in the energy cost unit is found to be around 5.5% by using the proposed method; moreover, the peak demand value is reduced by 9.7% when non-cooperative end-users becomes cooperative.

Aspetar Clinical Guideline: Ramadan Fasting and Exercise for Healthy Individuals

During the Islamic holy month of Ramadan, healthy adult Muslims observe fasting as an integral part of their religious practice. This dawn to dust daily fasting regimen for over 29-30 days involves strict adherence to various lifestyle aspects, including nutrition, hydration, and sleep patterns, which can potentially influence physical performance. It is often observed that Ramadan fasting may deter athletes from training and participating in competitions, and it can also discourage the general community from engaging in physical exercise. This situation can place practicing Muslim athletes at a competitive disadvantage. Therefore, the objective of this clinical guideline was to offer practical recommendations, supported by consensus from an expert panel, for healthy athletes and their support teams on how to effectively adapt their behavioural, social, and psychological strategies to cope with the changes and constraints imposed by Ramadan fasting. The scope of these recommendations extends beyond merely prescribing appropriate exercise routines during the month of Ramadan, but also encompassing considerations like scheduling, intensity, duration, exercise type, and training load. Additionally, the recommendations address various aspects of lifestyle, including nutrition, hydration, and sleep, while also delving into psychosocial and cognitive facets related to Ramadan fasting. It is important to emphasize that these recommendations are intended for healthy individuals. Patients with chronic illnesses should consult their healthcare providers to ensure that they can safely practice Ramadan fasting.

Integrated Energy Management of Smart Grids in Smart Cities Based on PSO Scheduling Models

The supporting position and role of smart grids in the construction of smart cities have not been fully explored. Based on systematizing the system architecture of smart cities, we first analyze the facilitating and constraining roles of smart grids and smart cities with each other and make a quantitative analysis of the coordination and supporting roles between them; in the smart grid environment, we propose a framework of energy management system based on particle swarm optimization (PSO) dispatching model. The algorithm optimizes the operation of dispatchable loads, electric vehicles, and energy storage systems based on outdoor temperature forecasts, renewable energy power output forecasts, day-ahead tariff signals, and customer preferences to minimize customer electricity costs. The performance of the algorithm is verified through simulation experiments, and the results show that the proposed algorithm significantly reduces electricity consumption costs by 32.54% compared to algorithms that only optimize the scheduling of loads or some components of the home energy management system.

ОПТИМІЗАЦІЯ ГРАФІКІВ ЕЛЕКТРИЧНОГО НАВАНТАЖЕННЯ АГРЕГАТОРОМ У ЛОКАЛЬНИХ ЕЛЕКТРОЕНЕРГЕТИЧНИХ СИСТЕМАХ

The market operation of the electricity distribution system has gained significant expansion due to the growing use of renewable and distributed sources. This paper presents strategies for optimizing load schedules by aggregators of local systems. Optimization of load schedules is to minimize the total costs of the supplier to reduce the cost of electricity and lower prices for the consumer. In local systems, which include diesel generators, the main component that most affects the price per 1 kW is the consumption of primary fuel of diesel generators. The objective function proposed in this study minimizes the supplier's primary fuel consumption by optimally redistributing power to each generator. The basic load schedule and application of schedule optimization strategies were studied: load reduction, load transfer, increase of minimum loads, flexible load change. When using the optimal algorithm, the costs are 5-6% relative to the uniform power distribution. Ref. 8, fig. 4, table. Key words: local system, diesel-generator, load schedule, aggregator.

Empirical Validation of Fuzzy Logic Based Predictive Load Scheduling in Mimic Home Energy Management System

<p>Load scheduling plays a vital role in the home energy management systems. The main objective of this load scheduling is to balance the power demand and supply power without degrading the performance of the loads and consumers tolerance. Though many research works concentrate on load scheduling, very few works concentrated on real time scenario. On the other hand, research work concentrated on optimal load scheduling through fuzzy logic requires incorporation of fuzzy based system in either simulated or real-time home energy management system. Hence, the proposal aims to schedule the loads in a simulated home energy management system through fuzzy logic controller using MATLAB Simscape with required subsystems. The proposed simulated environment considers four different resistive loads. Intelligent scheduling is aimed to achieve efficient load scheduling. A fuzzy controller has three inputs namely integrated source, state of charge of battery, and power demand whereas probability of scheduling is considered as output. The efficiency of the proposed fuzzy-based load scheduling scheme is evaluated under various load conditions for different sub-systems with varying input power. The results exhibit the efficacy of the proposed scheme.</p> <p> </p>

Cloud computing: an efficient load balancing and scheduling of task method using a hybrid optimization algorithm

<p>The cloud computing trend on the internet is vital as it allows data and applications to be managed over the internet instead of requiring personal devices. The job of users is scheduled in the resources of the cloud in order to improve performance. Schedu ling tasks is an non - deterministic polynomial (NP) - hard problem, as it may have multiple solutions. Various researchers have proposed different load balancing and job scheduling algorithms to optimize the scheduling process in cloud environments, each with disadvantages. Therefore, this research proposes a novel hybrid load balancing and scheduling of tasks by the whale optimization algo rithm (WOA) and seagull optimization algorithm (SOA) in the cloud. This hybrid proposed whale - seagull optimization algorithm (WSOA) optimizes task scheduling in the cloud b y reducing processing time, response, and execution time, maximizing central processing unit (CPU) utilization, memory utilization, throughput, reliability, and balancing the load. The algorithm is simulated using the CloudSim toolkit package. As compared with existing approaches, simulation results showed better performance in terms of response time, processing time, execution time, CPU utilization, memory utilization, throughput, and reliability and is analyzed by comparing with the harries hawks optimiza tion (HHO), hybrid dragonfly and firefly algorithm (ADA), spider monkey algorithm (SMA) and bird swarm optimization (BSO).</p>

Research on optimal dispatch of microgrid with dispatchable load

With the rapid development of society, traditional energy has become increasingly scarce and the problem of environmental pollution has intensified. By analyzing the objective functions of gas turbine, battery, photovoltaic power generation, and wind power generation, their constraints are established, and a microgrid optimal dispatching system is established. Using the idea of particle swarm optimization algorithm, an optimal dispatching model of microgrid with schedulable load is proposed. The particle swarm optimization algorithm runs in the optimal strategy algorithm of MATLAB to predict the optimal dispatching transmission time of the dispatchable load, and finally, minimize the total operating cost of the microgrid system by comparing the output before and after distributed generation in the system and the total load of the system.

Burst-Aware Time-Triggered Flow Scheduling With Enhanced Multi-CQF in Time-Sensitive Networks

Deterministic transmission guarantee in time-sensitive networks (TSN) relies on queue models (such as CQF, TAS, ATS) and resource scheduling algorithms. Thanks to its ease of use, the CQF queue model has been widely adopted. However, the existing resource scheduling algorithms of CQF model only focus on periodic time-triggered (TT) flows without consideration of bursting flows. Considering that the bursting flows often carry high-priority data in real systems, in this paper we investigate the mixed-flow (i.e., TT and bursting flows) scheduling problem in CQF-based TSN aiming to maximize the number of schedulable flows and system load balance while satisfying the deterministic demands of delay, jitter, and reliability for both TT and bursting flows. Unfortunately, it is challenging to schedule the mixed flows with the original CQF model because of the huge difference between TT and bursting flows. To resolve this problem, we firstly design an enhanced Multi-CQF model to satisfy the basic demands of bursting flows sent at any time without affecting the deterministic transmission of TT flows. Given the complexity of mixed-flow scheduling and the proposed queue model, it is difficult for traditional algorithms to fully utilize network resources. Thus, we further propose a time-correlated DRL resource scheduling (TimeDRS) algorithm to optimize the resource allocation. TimeDRS can be extended to other time-related resource scheduling scenarios, such as TDMA-based scheduling. Experimental results demonstrate that our proposed approaches can greatly reduce frame loss and end-to-end latency for bursting flows, and well balance runtime and schedulability compared with state-of-the-art benchmarks.

Dispatching Method of Distributed Energy Storage Resources in Substation Based on Peak-shaving Compensation Response Model

The conventional distributed energy storage resource scheduling method is mainly based on automatic load demand response scheduling, and the load response gap between peak hours and low hours is large, which affects the economic benefits of energy storage resource scheduling. Therefore, a distributed energy storage resource scheduling method based on a peak shaving compensation response model is designed. The cluster scheduling characteristics of distributed energy storage resources are extracted, and the distributed energy storage resources are charged and discharged synchronously at the same scheduling node. Combined with the resource scheduling strategy of the substation, the scheduling load of energy storage resources is limited so that the scheduling impact on the substation power grid is reduced. Based on the peak-shaving compensation response model, the dispatching objective function of distributed energy storage resources in the substation is optimized, the dispatching of distributed energy storage resources in the substation is optimized from the perspective of safe and economic operation, and the stochastic error of distributed energy storage resource scheduling is avoided in the form of a compensation response constraint to meet the resource scheduling requirements. Comparative experiments show that this method is more economical and can be applied to real life.

Two-stage robust scheduling and real-time load control of community microgrid with multiple uncertainties

With the increasing popularity of wind and solar generation, the stable and economic operation of the community microgrid system become more challenging. This paper is concerned with the robust scheduling and real-time control of demand response (DR) air conditioning (AC) loads for community microgrid. Firstly, a two-stage robust scheduling model coupled by the day-ahead dispatch and real-time dispatch is established by considering the uncertainties of wind/photovoltaic power generation and loads. Moreover, the incorporation of multiple interval uncertain sets is introduced to characterize the uncertainties related to wind power, photovoltaics, and load, thereby reducing the conservativeness of the model. Secondly, the real-time control of AC loads by adjusting the on/off actions and temperature setpoints with limited impact on user comfort so as to track the optimized electricity consumption curve. Finally, the simulation results show the effectiveness and robustness of the proposed optimization dispatch and real-time control algorithm.

An AC optimal power flow framework for active–reactive power scheduling considering generator capability curve

AbstractThis paper presents a simplified optimal power flow (OPF) framework to facilitate co‐optimised active and reactive power scheduling for synchronous generators and price‐sensitive demands. The proposed framework creates an opportunity for generators and loads to simultaneously participate in a combined market for active and reactive power. The co‐optimisation of active and reactive power generation is constrained by the interdependence of the active and reactive power capacities, which is represented by the generator capability curve. Thus, a detailed mathematical derivation of the opportunity costs across various regions of the generator capability curve is presented. This study considers a detailed generator capability curve that considers the armature, field, under‐excitation, and prime mover limits. The interdependence of active and reactive power consumption for demand is modelled using the concept of power‐factor. The OPF problem for generator and load scheduling is formulated as a non‐linear optimisation task, leveraging the inherent properties of the generator capability curve, that is, piecewise smoothness, continuity, and the monotonically increasing slope magnitudes. Furthermore, to simplify the OPF formulation, the non‐linear capability curve is represented as a combination of the linear curves. To demonstrate the effectiveness of the proposed OPF methodologies, suitable case studies are conducted using different test systems.

A Systematic Tri-level Demand-driven Supply-side Management Approach on Enhancing Building Energy Performance in an Educational Institution

The concept of demand-side management (DSM) is a ceaseless research topic craving an advanced, superior, and qualitative strategy for improving customers’ level of satisfaction with energy utilization. It encourages the active participation of prosumers and paves the way for sufficient energy proficiency. However, less attention is paid to accounting for consumers’ comfort and priorities. This paper presents a tri-level systematic approach for implementing demand-side and supply-side management at the consumer end. The proposed Tri-level Demand-Driven Supply-Side Management (TDD-SSM) framework commences with gathering knowledge on available loads in the department building block of a higher educational institution situated in the Madurai district of Tamil Nadu, India. The incorporated DSM technique follows strategic load categorization and load scheduling. Following that, a feasibility study on optimal sources is accomplished with Hybrid Optimization of Multiple Energy Resources software. The simulation is done to have a clear comparison in rendering a techno-enviro-economically feasible configuration of energy source to loads (with and without DSM). Ultimately, the framework concludes by picking the most promising energy configuration through the ideal computational multi-criteria decision-making–Preference Ranking Organization Method for Enrichment Evaluation II approach, which highlights the energy configuration of photovoltaic solar generation supply along with grid feeding loads after DSM incorporation and is found to be the best energy configuration under techno-enviro-economic criteria.

EXPANDING THE POSSIBILITIES OF USING ENERGY STORAGE AND GENERATION SYSTEMS WITH RENEWABLE SOURCES FOR ENERGY SUPPLY OF RAILWAY INFRASTRUCTURE FACILITIES

The article analyzes the options for implementing renewable energy systems and energy storage on railway infrastructure and rolling stock. It is noted that the energy sector of the railway infrastructure of Ukraine, as well as some European countries, is not diversified by energy sources, and the use of renewable energy sources (RES) is limited. The possibility of using hybrid systems with photovoltaic batteries and a wind generator to meet the electricity needs of the railway infrastructure facility is considered. The concept of a regulated railway crossing operating on renewable energy sources (RES) in combination with electric vehicles (electric bicycle and electric tire) is proposed, which will ensure the balancing of the hybrid power supply system, storage of excess RES energy and generation of additional energy as needed. In accordance with the proposed concept, possible scenarios for the functioning of the railway crossing load were identified. The electricity consumption is estimated and a typical load schedule for a railway crossing is determined.

Multi-objective global dynamic optimal scheduling of smart building loads considering carbon emissions

In recent years, there has been a significant increase in electricity consumption and carbon emissions from households in smart buildings. This increase has had a profound impact on the economic aspects of residential electricity consumption and the achievement of the national dual carbon goal. In this paper, an optimal scheduling model for household loads in smart buildings is established. It considers the user demand side, grid-side supply, and the impact of the PV energy storage system (PESS) on carbon emissions. The optimization objectives are the economy of household electricity consumption and the total deviation of electricity consumption. Second, the adaptive mixed inverse learning strategy multi-objective beluga optimization algorithm (AMOBWO) is adopted to enhance its overall dynamic optimization. This optimization addresses challenges such as the uneven distribution of electricity consumption, load timing constraints, power limitations, and uncertainty in electricity consumption during the scheduling of smart building loads. Finally, the results demonstrate that AMOBWO decreases the total cost of household electricity consumption in smart buildings by 59.32% (based on the selected maximum PV capacity). Additionally, it reduces the total deviation by 14.28% after optimal scheduling. As the PESS capacity increases, there is a significant reduction in the indirect carbon emissions from smart buildings, decreasing from 881.279 kg CO2 to 431.299 kg CO2.

A two-stage distributed optimization method for home energy management systems via multi-modal data-driven algorithm

The home energy management system (HEMS), which utilizes multi-modal data from multiple sensors to generate the knowledge about decision making, is essential to the optimization of home energy management efficiency. Load scheduling based on HEMS can improve the utilization efficiency of multi-modal data and derived knowledge, achieve power supply-demand balance, and reduce users’ electricity costs. This paper proposes a distributed load optimization scheduling method for the load scheduling problem in HEMS based on multi-modal data-driven algorithm. Additionally, a two-stage data-driven optimization method is proposed, including a first-stage optimization model based on minimizing electricity costs and a second-stage optimization model based on minimizing system load fluctuations. In the first stage, cost self-optimization is performed based on energy storage devices. In the second stage, a load optimization instruction is issued by the control center, and each user optimizes the load fluctuations based on the system load data. Compared to centralized control methods, this approach reduces the computational overhead of the control center. Finally, simulation experiments based on load scheduling in the HEMS are conducted. The results of the first optimization stage show that when the battery capacity integrated into the system increases from 3.68 kWh to 6.68 kWh, user costs can be reduced from 57.572 cents to 42.064 cents. It is not only evident that the proposed method can effectively save users on electricity costs, but the introduction of larger capacity batteries also lowers these costs. The second stage of load fluctuation optimization results show that the proposed method can effectively optimize the usage data of a group of users and decrease the absolute peak-valley difference by 8.8%.

Demand Side Management In Smart Grid Optimization Using Artificial Fish Swarm Algorithm

The demand side management and their response including peak shaving approaches and motivations with shiftable load scheduling strategies advantages are the main focus of this paper. A recent real-time pricing model for regulating energy demand is proposed after a survey of literature-based demand side management techniques. Lack of user’s resources needed to change their energy consumption for the system's overall benefit. The recommended strategy involves modern system identification and administration that would enable user side load control. This might assist in balancing the demand and supply sides more effectively while also lowering peak demand and enhancing system efficiency. The AFSA and BFO algorithms are combined in this study to handle the optimization of difficult problems in a range of industries. Although the BFO will be used to exploit the search space and converge to the optimum solution, the AFSA will be used to explore the search space and retain variation. In terms of reduction of peak demand, energy consumption, and user satisfaction, the AFSA-BFO hybrid algorithm outperforms previous techniques in the field of demand side management in a smart grid context, using an AFSA. According to simulation results, the genetic algorithm successfully reduces PAR and power consumption expenses.

Dynamics between warehouse operations and vehicle routing

When scheduling the distribution of ordered items from a warehouse to customers, the transportation planning is generally done first and serves as input for planning warehouse operations. Such a sequential approach can lead to substantial inefficiencies when the customer deliveries are restricted by time windows, and the warehouse has limited resources available (both order pickers and space in the staging area). This paper studies the trade‐offs between warehouse operations and transportation planning. The goal is to understand the impact of three specific managerial interventions: adopting an integrated planning approach, expanding the available staging space, and expanding the delivery time windows. To this end, we propose a mathematical model for a general vehicle routing problem that incorporates order batching, order picker scheduling, staging, and vehicle loading. We introduce a novel idea to express the picking time of an order batch as a function of the batch size and develop a metaheuristic to solve this integrated problem. Furthermore, we develop exact algorithms to provide optimal solutions for the individual warehouse and transportation problems in a sequential planning approach. Managerial insights are distilled from case studies in two warehouses, one for ambient products and the other for refrigerated products, of a leading grocery retailer in the Netherlands. Our results show that integrated planning outperforms the other managerial interventions and generates cost savings between 9% and 11%. Savings are generally realized by executing larger order batch sizes to be picked in the warehouses at the expense of additional routing cost (around 2–3%). The second intervention in the form of time window expansions of only 15 minutes for customer deliveries can lead to cost savings between 4% and 6%, which results from a reduction in both transportation and warehousing cost. Expanding the capacity of the staging area is only meaningful when the staging space is highly utilized and only results in cost savings for the warehouse operations.

Container Power Consumption Prediction Based on GBRT-PL for Edge Servers in Smart City

Edge computing and IoT devices have been widely deployed in smart city applications due to the rapid promotion and implementation of 5G communication technology. Limited by power supply and hardware computing capability, applications on edge servers are mostly deployed and run in the form of container micro-services to improve resource utilization. Therefore, identifying the power consumption at the container granularity is of great importance for the load scheduling and service quality assurance of edge servers. In this paper, a GBRT-PL-based container power prediction method is proposed. Performance metrics with a strong correlation between container and server power consumption are selected for power consumption modeling. To effectively suit the nonlinear relationship between container performance metrics and server power consumption, the integrated predictive capabilities of multiple regression trees and the segmented linear model of single regression tree leaf nodes are applied. The data from the experiments prove that the GBRT-PL model predicts power consumption more accurately than other models for single and multiple container groups. The highest average relative error rate in the four multi-container group tests is 6.72%, whereas the highest relative error rate in the 90% quantile is 11.66%. In addition, it can accurately predict the majority of power consumption peaks, which contributes to the precise detection of power consumption anomalies.

Strategic planning of distribution network integrated with EV charging stations using fuzzy pareto optimality for performance improvement and grid-side emission reduction benefits

The increasing penetration of electric vehicles (EVs) in distribution systems requires efficient charging load management techniques for delivering high-quality power to consumers. In this paper, we proposed a strategic planning approach for distribution systems integrated with EV charging stations, employing fuzzy Pareto optimality to enhance system performance and minimize carbon emissions. Our approach involves a fuzzy Pareto heuristic network reconfiguration to minimize real power loss and improve voltage profiles. Additionally, Time of Use (ToU) pricing-based EV charging load scheduling is developed to minimize the annual energy cost. These objectives aim to improve minimum node voltage, reduce power losses, and maintain branch current constraints. To simulate the impact of EV charging loads, we aggregate residential, commercial, and industrial loads, along with EV charging loads at charging stations based on customer choice time and ToU pricing methods. The proposed reconfiguration approach is tested on 33 and 69-bus distribution systems with integrated EV charging stations, distributed generations (DGs), and shunt capacitors (SCs). The simulation results demonstrate the advantages of the reconfiguration algorithm in enhancing the performance of the distribution network in the presence of EV loads. Furthermore, we compare ToU pricing-based EV charging time zones with customer comfort-based EV charging, showcasing the advantages of the former in reducing emissions through real power loss reduction. Overall, our strategic planning approach not only improves distribution system performance but also offers economic benefits while minimizing carbon dioxide emissions.