The robotic mobile fulfillment system (RMFS) is a parts-to-picker material handling system that has emerged in e-commerce warehouses and aims to save labor costs and achieve higher picking efficiency. This study investigates an RMFS in high-density storage warehouses with limited space or high rental costs. Supposing that the incoming orders have been preprocessed, we focus on how to carry specific

Despite impressive advances in Artificial Intelligence (AI)-based gameplaying in recent years, many such systems still lack the capability of robustly dealing with novelty in a sufficiently rich environment. Novelty may be operationally described as the states or situations that violate (implicit or explicit) assumptions about agents, the environment, and agent–agent and agent–environment interactions

This research compares the impact of infrastructure congestion management initiatives at a bulk cargo marine terminal on truck queuing and emissions. Researchers have studied the impact of individual congestion management initiatives in marine terminals extensively. However, limited research has been conducted to comparatively evaluate the impact of several initiatives. Furthermore, researchers have

High-rise teaching buildings are complex public buildings integrating the evacuation risk of teaching buildings and high-rise buildings. In this regard, studying the evacuation characteristics of high-rise teaching buildings is paramount for a safe and fast evacuation. In this paper, we first analysed whether the obstacles in the classrooms would be beneficial to the overall evacuation. Obstacle and

The loss of situational awareness by pilots is one of the harshest risk factors leading to catastrophic accidents. In this paper a situational awareness analysis model based on multiple agents is presented to simulate the human-computer interaction process in the aircraft cockpit. From the perspective of human-in-loop, the integrated model consists of modularized pilot agent model, technical system

In cloud computing environments, when a client wants to access any resources, hardware components, or application services, he needs to get a subscription for the same from service providers. The usages of each client are monitored over a network by service providers and later on user will be charged for the services used. Cloud service provider is responsible for providing Quality of Service to clients

In this study, a previously developed co-simulation method has been expanded to also simulate the dynamic behaviour of sealing gap regions in hydraulic percussion units. This approach is based on a 1D system model representing the fluid components and a 3D finite element model representing the structural parts of a hydraulic hammer. The sealing gap is a fundamental feature of a percussion unit, where

This paper presents an improved vibration control method that controls the amplitudes of residual vibrations of a flexible non-uniform shaped manipulator with higher suppression ratio. The proposed new method suppresses the residual vibrations that occur after motion by shaping the velocity input. By considering the parameters of the experimental system, an analytical model is established according

As an important design parameter for bucket wheel excavator, the cutting resistance of the bucket wheel shows significant dynamic character and changes drastically under different work conditions. Therefore, this paper analyzes the trend of cutting resistance through a combination of discrete element method (DEM) and design of experiment (DOE). Firstly, the three-dimensional dynamic simulation of tool-particle

Finite element (FE) simulation is an efficient and time-saving method to optimize the high-speed machining process of aluminum (Al) alloy. The constitutive model accurately described the dynamic mechanical behavior of materials at cutting conditions is the premise of obtaining high-precision simulation results. In this study, the flow stress-strain relationship of AA 6061-T6 is obtained at a high temperature

Some popular applications of wireless power transfer (such as electric vehicle charging) include a transmitter residing on a static platform (charging station) and a dynamic receiver (vehicle). In such applications, compensation may be excluded from the receiver in order to minimize, simplify and lower the cost. If transmitter compensation is also maximally simplified series to none (SN) compensation

When exploring hybrid cloud solutions, the provision of cloud computing resources by more than one provider, may result in important gains, such as better risk management, improvement of operational efficiency and avoidance of the lock-in effect by a single vendor. To this end, many enterprises decide to rely on hybrid strategies and multiple cloud providers. With the strategic distribution of the

Fog computing is one of the most important emerging paradigms in recent technological development. It alleviates several limitations of cloud computing by bringing computation, communication, storage, and real-time services near to the end-users. However, with the rapid development of automation in smart cities, the number of task executions by fog nodes are increasing, requiring additional fog nodes

One of the significant limitations in the evaluation of hybrid clouds is the difficulty in validating new solutions by their deployment in real systems since replication of tests on large environments is usually highly expensive. To overcome these limitations, simulators have become popular for conducting preliminary tests. However, there is still a lack of simulation tools with easy-to-use code that

Windage power loss, a form of load-independent power loss, is always one of the hotspots for reducing fuel consumption and overall weight in aero-engine applications. This paper represents a considerable improvement in the analytical model for estimating the losses of spiral bevel gears and proposes a novel overset mesh method for the prediction of the windage losses. The improved analytical model

System dynamics (SD) is an established discipline to model and simulate complex dynamic systems. The primary goal of SD is to evaluate and design new policies that can impact the system under study in a desired way. Policy design, that is, identifying effective model levers, however, is a challenge and in many cases trial-and-error driven. In this article, we introduce a new and coherent framework

As the merging section of an urban expressway main road and on-ramp traffic flow, on-ramp areas have serious merging conflicts. In the dynamic game between two streams of traffic flow, traffic congestion can occur and cause bottlenecks on expressways. With the development of vehicle intelligence and network technology, connected vehicles can form a platoon or a group and realize real-time dynamic communication

The researcher's predilection towards the concerned infinite resources and the dynamic provisioning on rental premises encourages the scheduling of complex scientific applications in the cloud. The scheduling of workflows in the cloud is constrained to QoS parameters. Many heuristic and meta-heuristic algorithms are widely investigated for the QoS constrained workflow scheduling problem. However, it

The scientific workflows are high-level complex applications that demand more computing power. The cloud data center (CDC) remains one of the essential models of economic infrastructure for workflow applications. These CDCs consume a lot of electric power while running workflow applications. Hence, efficient energy-aware scheduling techniques are required to perform the task to a virtual machine (VM)

Technological advancements have focused increasing attention on Automated Mobility-on-Demand (AMOD) as a promising solution that may improve future urban mobility. During the last decade, extensive research has been conducted on the design and evaluation of AMOD systems using simulation models. This paper adds to this growing body of literature by investigating the network impacts of AMOD through high-fidelity

Hybrid Cloud environments allow the utilization of local resources in private Clouds with resources from public Clouds when needed. Such environments represent systems with high failure rates because they feature heterogeneous components, a large number of servers with intensive workload are built as complex architectures. For these reasons, the availability of such systems could be easily compromised

The accuracy of a machining model depends on the capability of this model to describe the physical phenomena associated to the real machining system. This includes the material constitutive model and the approach used to describe the field flow of the material in cutting. In this paper, a model of high speed machining (HSM) of Ti6Al4V titanium alloy is developed. This cutting model includes the proposed

Empirical evidence suggests that evacuees tend to break down their well-coordinated motion and adopt competitive egress behaviour when they are confronting life-endangering situations (e.g., fire accident, earthquake). This phenomenon significantly influences crowd dynamics, and subsequently, the overall evacuation time. In this paper, a novel evacuation model has been developed, which takes the detailed

Fog computing is an emerging service-oriented market in conjunction with Cloud computing to fulfill the resource demand of mobile users as well as IoT users for real-time applications. Auctioning in Fog computing is highly challenging due to mobility, dynamic pricing, real-time demand in comparison to Cloud based auctioning models. Further, due to users’ mobility and limited Fog resources, existing

In recent years, building business applications from independently developed services has become one of the current trends in service computing. To satisfy clients’ requirements, service composition is performed to compose the various capabilities of available services. With the proliferation of services having similar functionalities, assessing the quality of a given composition is a paramount factor

Due to the complex structure of a distributed energy resources system (DES) and a large amount of sensor data, local computers cannot provide enough computing resources to process the related data in a short time. Moreover, network integration causes a power system vulnerable to denial of service (DoS) attacks. DoS attacks result in the loss of partial sensor data, which affects the control performance

In the design process of a hybrid cloud with the purpose of cost optimization, finding the optimal distribution between the resources to be deployed in both private and public clouds is a complex task. To help the cloud designer in this task, optimizer and simulation tools can be used. In the research presented in this paper, a state-of-the-art optimizer tool, designed for the optimal allocation of

From climate action to public health measures, human collective endeavors are often shaped by different uncertainties. Here we introduce a novel population-based learning model wherein a group of individuals facing a collective risk dilemma acquire their strategies over time through reinforcement learning, while handling different sources of uncertainty. In such an N-person collective risk dilemma

Internet of Underwater Things (IoUT) is growing an attractive zone of the research to explore the underwater scenario for surveillance. The autonomous manner of Unmanned Aerial Vehicles (UAV) or Drone makes search and surveillance of the target underwater region effectively. Drone gather, analyse, and transmit data at the time of flight by consuming battery energy. Underwater search and monitoring

The COVID-19 emergency suddenly obliged schools and universities around the world to deliver on-line lectures and services. While the urgency of response resulted in a fast and massive adoption of standard, public on-line platforms, generally owned by big players in the digital services market, this does not sufficiently take into account privacy-related and security-related issues and potential legal

Various numerical models have been used to understand and predict ocean dynamics. For this reason, many information technology (IT) resources are required for high-resolution global ocean modeling. The development of cloud-computing technologies has enabled earth scientists to easily use numerical ocean models that require high-performance computing (HPC) and message-passing interface (MPI) software

Healthcare is one of the most important disciplines to ensure life quality for human beings, especially in unpredictable scenarios such as accidents, natural disasters, or terrorism. In these cases, Emergency Medical Services (EMS) face significant challenges due to the complex nature of pre-hospital events, coordinating several resources according to the collected information in a short time. In this

Modeling of air quality is a statistical simulation of how air pollutants spread and react in the environment to impact the quality of atmospheric air. A 2-Phase assessment simulation model is presented to assess air quality to evaluate the toxic level of each pollutant in the air, which can harm the health of sensitive people. The first phase calculates the score for each factor of air quality using

Safeguarding and type approval of automated vehicles is a key enabler for their market launch in our complex traffic environment. Scenario-based testing by means of computer simulation is becoming increasingly important to cope with the enormous complexity and effort. However, there is a huge gap when assessing the safety of the virtual vehicle while the real vehicle will drive on the road. Simulation

The Internet of Things has reached the industry. Allowing connectivity from production plants to the Internet requires appropriate security mechanisms to provide protection against cyber attackers. In this paper, we propose a security architecture for a gateway connecting sensors and automation components from assembly lines with Internet or cloud based systems. A Trusted Platform Module (TPM) is used

In-laboratory mobile device data gathering is useful to support fields of study that rely on data derived from mobile devices as elementary research input. Particularly, Dew Computing, a sub-area of mobile distributed computing, aims at scavenging idle computing resources from mobile devices at the edge. To produce repeatable experiments for developed Dew approaches, simulation of relevant mobile device

Cloud computing has been making significant contributions to Internet of Things, Big Data, and many other cutting-edge research areas in recent years. To deal with the cloud bursting, on-premises private clouds often extend their service capacity with off-premises public clouds, which causes the migration of jobs and their corresponding data from private clouds to public clouds. For jobs executed in

A Cyber–Physical System (CPS) comprises physical as well as software subsystems. Simulation-based approaches are typically used to support design and Verification and Validation (V&V) of CPSs in several domains such as: aerospace, defence, automotive, smart grid and healthcare. Accordingly, many simulation-based tools are available to support CPS design. This, on one side, enables designers to choose

The credibility evaluation method for a single simulation model is relatively mature at present. While there is still a great need to provide an effective credibility evaluation method for complex simulation systems, which is the basic premise to assist the design, test, evaluation and optimization of a complex research object based on constructing its simulation system. In this paper a credibility

The goal of Internet of Things (IoT) is to bring any object online, thereby creating a massive volume of data that can overwhelm the existing computing and networking technologies. Therefore, centered cloud isn't ideal for rapidly expanding IoT environmental requirements. Fog computing (FC) moves some portion of the computing load (related to real-time services) from the cloud into edge fog devices

The products that lose their initial value after a time period are known as deteriorating products and need more appropriate decisions for optimization in a closed-loop supply chain. The studied closed-loop supply chain consists of a manufacturer and a distributing center that are producing and distributing a deteriorating product to customers. The deteriorating products are collected from distribution

Blockchain works according to the principles of distributed transactions and processing tiny hash-based blocks. Data located in the blockchain preserves its integrity and transparency, which enables participants to verify it. Today, people apply blockchain technology in domains that must maintain the integrity of the data. However, people can be reluctant to introduce blockchain technology due to the

The “Internet of Things” (IoT) provide humans and smart objects with attractive services, based on the advanced features of the IoT devices, like high sensing, real-time acting and reasoning. In our previous research we have highlighted that these features can be improved by promoting cooperation between smart objects, and we introduced the association between Multi-Agent Systems and IoT devices. In

The present study aims to solve a system-level problem regarding a journal bearings-gear pump based on a novel simulation model. The developed model consists of different modules: a fluid dynamic model for the pump, a lubrication model for the bearings, a model for the evaluation of shaft motion and a geometrical model. Cavitation models, i.e., the Jakobsson-Floberg-Olsson (JFO)-based model for bearing

Research on the effective use of joint-legged robots continues rapidly in many sectors. However, studies on pentapod robots are rare. In this study, a heavy-duty 5-legged robot on which a manipulator's arm with 3-axis and rotating joints is placed was modeled in a Matlab Simscape Multibody environment. The walking simulations of the robot and the position control of the manipulator arm were carried

Hydro-pneumatic or air suspension might have superior ride quality, yet their severe damage could be too expensive for small-amateur rally teams, difficult, and time-consuming to be solved in the rally service park which has time limitation. Small teams also often struggle to recognize the true performance of their suspension system since full vehicle testing and validation is often performed late

Cloud computing offers computational, storage, and applications capabilities as subscription oriented services. It offers a platform explore computational assets and use them based on "pay per use arrangement". Thus it opens ways to access boundless assets with negligible equipment and programming at the customers' end. This paper focuses on the advancement of a cloud administration's provisioning

Simulating the dynamics and evolution of metropolitan transportation systems serving millions of travelers remains a difficult task, beyond existing standard software's abilities. MATSim (Multi-Agent Transportation Simulation) is the only high-resolution spatially-explicit framework that allows intrinsic population downscaling - simulating the entire system's dynamics based only on a fraction k of

The development of local energy communities and collective self-consumption framework at a large scale requires new control methods that take into account users preferences. This article presents a model of such a community, with diverse actors (photovoltaic generators, electric vehicles, storage system and tertiary buildings). Game theory is used to model the preferences of each user and to build

Early modeling and simulation models used in obesity research tended to be highly detailed on weight dynamics within the body or provided a very simplified view of socio-environmental influences by portraying obesity as a contagious disease (e.g., where weight directly ‘spreads’ among peers). The 2010’s have witnessed the emergence of simulations for obesity as a new interdisciplinary field of research

Mixed-traffic intersections with high-density bicycle traffic flow are one of the most common bottlenecks in the urban traffic network. Due to the shared space and frequent interactions among heterogeneous road users, through bicycle flow shows an obvious tendency of lateral dispersion, resulting in a reduction in traffic efficiency and safety at intersections. A precise evaluation of its impacts on

The embedded system developers often need to perform software testing even when the target hardware is inaccessible. Due to the inaccessibility of the hardware, the hardware-software interaction testing becomes a challenging task. Researchers have tried to overcome this issue by developing an environment model that simulates the behavior of the actual hardware. In the existing literature, environment

Air-supported membrane buildings may suffer from air-leakage caused by the opening of exit, failure of inflation system or environmental force majeure, which is essential for pedestrians' evacuation but receives less attention. The paper proposes a coupling evacuation model based on multi-velocity cellular automaton by incorporating dynamic air-leakage process in evacuation analysis to quantitatively

Auto-scaling of Web applications is an extensively investigated issue in cloud computing. To evaluate auto-scaling mechanisms, the cloud community is facing considerable challenges on either real cloud platforms or custom test-beds. Challenges include – but not limited to – deployment impediments, the complexity of setting parameters, and most importantly, the cost of hosting and testing Web applications

Storage technology has emerged as an indispensable paradigm for processing various applications in cloud data centers. The storage infrastructure consisting of Hard Disk Drives (HDDs) and Solid-State Drives (SSDs) accounts for high energy consumption. Also, the trade-offs between HDDs and SSDs in terms of cost and energy consumption are extremely high. Therefore, disk-based storage subsystems need

Power consumption costs of computer fleets can be one of the main operational costs of medium or large-sized office sites. In order to optimise the power consumption of the fleet, a set of optimal power management policies must be generated and enforced. Generating these policies is an optimisation problem of finding the power off timeout value for each computer that maximises energy savings while

Computer simulations based on numerical methods applied to the equilibrium equations of Newtonian mechanics have significant impact in many industries, because they provide cheaper development of products. Using computer simulations, it is possible to investigate behavior of product parts and assemblies under different boundary conditions, loads and applied materials, which significantly reduces the

In this work, a toolchain for the solidification and the shrinkage of cast salt cores used in high-pressure die casting is implemented in the open-source computational fluid dynamics (CFD) library FOAM-extend to evaluate the displacements resulting from residual stresses. The toolchain consists of three stages, which first calculate the phase change, then generate the residual temperatures and finally