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Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time systems. Smart cities, smart homes, ambient intelligent systems, or network-centric defense systems are among these application domains. Data Distribution Service (DDS) is a communication mechanism based on Data-Centric Publish-Subscribe (DCPS) model. It is used for distributed systems with real-time operational constraints. Java Message Service (JMS) is a messaging standard for enterprise systems using Service Oriented Architecture (SOA) for non-real-time operations. JMS allows Java programs to exchange messages in a loosely coupled fashion. JMS also supports sending and receiving messages using a messaging queue and a publish-subscribe interface. In this article, we propose an architecture enabling the automated integration of distributed real-time and non-real-time systems. We test our proposed architecture using a distributed Command, Control, Communications, Computers, and Intelligence (C4I) system. The system has DDS-based real-time Combat Management System components deployed to naval warships, and SOA-based non-real-time Command and Control components used at headquarters. The proposed solution enables the exchange of data between these two systems efficiently. We compare the proposed solution with a similar study. Our solution is superior in terms of automation support, ease of implementation, scalability, and performance.

Particle swarm optimization (PSO) is a popular method to solve the optimization problems. However, calculations for each particle will be excessive when the number of particles and complexity of the problem increases. As a result, the execution speed will be too slow to achieve the optimized solution. Thus, this paper proposes an automated design and optimization method for rotary MRF brakes and similar multi-physics problems. A modified PSO algorithm is developed for solving multi-physics engineering optimization problems. The difference between the proposed method and the conventional PSO is to split up the original single population into several subpopulations according to the division of labor. The distribution of tasks and the transfer of information to the next party have been inspired by behaviors of a hunting party. Simulation results show that the proposed modified PSO algorithm can overcome the problem of heavy computational burden of multi-physics problems while improving the accuracy. Wire type, MR fluid type, magnetic core material, and ideal current inputs have been determined by the optimization process. To the best of the authors’ knowledge, this multi-physics approach is novel for optimizing rotary MRF brakes and the developed PSO algorithm is capable of solving other multi-physics engineering optimization problems. The proposed method has showed both better performance compared to the conventional PSO and also has provided small, lightweight, high impedance rotary MRF brake designs. Keywords: Particle swarm optimization (PSO), Multi-physics optimization problem, Rotary MRF brake, Heat transfer, Finite element

Simulating battle management is an essential technique used in planning and mission rehearsal as well as training. Simulation development costs tend to be high due to the complexity of cognitive system architectures in such applications. Due to this complexity, it takes significant effort for a simulation developer to comprehend the problem domain enough to capture accurately in a simulation code. Domain-specific languages (DSL) play an important role in narrowing the communication gap between the domain user and the developer and hence facilitate rapid development. In command and control (C2) applications, the coalition battle management language (C-BML) serves as a DSL for exchanging battle information among C2 systems, simulations, and autonomous elements. In this article, we use a rapid prototyping framework for cognitive agents and demonstrate deployment of agent systems by adopting the model driven engineering approach. To this end, we extend the use of C-BML and automatically transform it in a cognitive agent model, which is then used for adaptive decision making at runtime. As a result, during a simulation run, it is possible to initialize and modify an agent’s goal reasoning model. The cognitive agent models are based on the deliberative coherence theory, which provides a goal reasoning system in terms of coherence-driven agents.

In this paper, an automatic method based on computer vision for the detection of abandoned luggage/bag in public spaces is proposed. First, with the background subtraction and foreground modeling technique, objects that were not present in the previous frames and have appeared later on as a static object are detected and then whether they are luggage or not are determined using the Faster Region Proposal Convolutional Neural Network (Faster R-CNN) technique. At the same time, the person closest to the luggage is identified and defined as the owner. After that, the event analysis phase is being started. If the identified person is not in the luggage area within a certain period of time (e.g. 30 seconds), the luggage is defined as “abandoned” with a bounding box. The assessments show that the proposed approach is effective and rapid.

This article presents a novel rotary magnetorheological fluid device with inherently low off-state torque. The working principle of the device is similar to peristaltic pumps except the fluid remains inside the device and circulates continuously. Unlike other continuous rotation magnetorheological fluid devices, which operate in shear mode, the proposed device works in pressure driven flow mode. A proof of concept prototype with arbitrary dimensions is built and experimentally evaluated. Measured off-state torque is as low as 20 N.mm. Analytical model of the resistant torque and finite element simulations of the magnetic circuit are presented and validated with the experimental results. Using these models, an optimal device with similar off-state characteristics can be designed to fulfill specific requirements of size, weight, power and on-state torque. The proposed concept is promising especially for use in high precision haptic interfaces that require stability and transparency at the lower end of force spectrum. © 2018, The Brazilian Society of Mechanical Sciences and Engineering.

Today, many military software intensive systems such as command and control systems, military simulations and decision support systems require the same military knowledge found in the operation plans and orders, which are mostly imported to the system in an application specific form. Due to the increased need for interoperability among those systems, many domain specific languages arise in order to formalize the inputs and outputs to obtain machine processable knowledge. A major domain specific language is the Coalition Battle Management Language (C-BML), which is currently under development. In this work, a scenario is developed and a coalition combat organization that has unmanned surface vehicle (USV) units under its command is created for fighting piracy. The orders and reports related to the patrol mission for the USVs are set up and modelled using C-BML. In order to model the orders, functional and temporal analyses of the actions in the orders are performed. The representativeness of the military orders, reports and requests in the scope of the scenario domain in C-BML is examined. Discussions about the expressiveness of C-BML are offered from a C-BML adopter perspective. Furthermore, we anticipate that this study will serve as a guideline for further C-BML studies.

In this chapter, first we present how to implement the skeleton structure of a federate application. We, then, move on to how to implement a federate using the RTI basic services such as federation, data declaration, and object management services (IEEE 1516.1 2010).

In this chapter, we elaborate for beginners how to start developing an HLA compliant simulation from scratch. In this respect, this chapter presents some practical guidelines and hints. Please keep in mind that we are not trying to present a full simulation development process, such as FEDEP (IEEE Std 1516.3-2003 in Standard for IEEE Recommended Practice for High Level Architecture (HLA) Federation Development and Execution Process (FEDEP). IEEE, 2003) or DSEEP (IEEE Std 1730-2010 in IEEE Recommended Practice for Distributed Simulation Engineering and Execution Process (DSEEP). IEEE, New York, NY, 2010). We advise you to refer to (Topcu et al. in Distributed simulation: A model driven engineering approach. Springer International Publishing, Cham(Zug), 2016) for a full-blown federation development process model based on Model-Driven Engineering (MDE) principles.

In this chapter, we will show how to construct an object model, which is a key step of any federation development process. On top of HLA object model background given in Chaps. 2 and 4, we delve into the details of object model components by presenting examples. We also show how to create and use them by using the SimGe object model editor.

The objective of this chapter is to provide a gentle introduction to High Level Architecture (HLA). HLA is a standard architectural framework for distributed simulation. It is an enabler for simulation reuse, interoperability and composability. In this chapter, various aspects of the standard will be reviewed to furnish user with a comprehensive introduction. Furthermore, a case study that demonstrates how to develop an object model for an HLA federation will be presented.

In this chapter, we present how to begin constructing an object model. First, we give an overview of SimGe, a tool for the HLA-based distributed simulations. And then, we show how to use SimGe to manage federation development, federation architecture modeling, and object model construction.

In this chapter, we will cover relatively advanced topics for federation implementation, such as time management, where the theoretical background is given in Chap. 2. First, we go through the basics of time management. We will see how to utilize advanced federation management services such as save-and-restore and federation synchronization, data distribution management, and ownership management services in detail. The last section of this chapter brings up the handling of the entities in the form of multiple (joined) federates generated in a single application, and of multiple federation executions.

We can identify two approaches for realizing synergies between multi-agent systems and distributed simulation. The first one is to incorporate agents into a simulation environment, specifically into an HLA federation, using interoperability techniques. The second is to build an agent environment based on HLA so that the RTI is employed to serve as the medium for agent communication and management. For preliminaries, we briefly introduce agent-based simulation and describe a cognitive agent architecture as an example agent architecture. Then, we discuss these two integration approaches.

In this chapter, we will present a complete case study, named “Maritime Border Surveillance Using Unmanned Surface Vehicles,” which involves interoperability of an agent-based simulation and an HLA-based simulation. In addition, we discuss the implementation issues of an intensive 3D graphics federate application, which is typically involved in a human-in-the-loop simulation.

This paper describes a virtual prototyping (VP) system which is a part of an open source software package for an additive manufacturing (AM) process under development. The VP system facilitates the product development by uniting the AM process and virtual reality in order to produce digital prototypes. Moreover, it combines particle based and layer based processes by including powder-like particles as its basic material. These particles are used as color codes in the VP system. This coding enables obtaining basic building blocks in homogeneous state or in heterogeneous state by mixing with other particles. These blocks or bricks are collated side by side to obtain the heterogeneous material property all over the solid body. The thin layers obtained by these bricks are then subsequently stacked up to fabricate a virtual prototype. Construction of multiple material prototypes is possible due to selective-additive nature of this process. The effectiveness of the proposed system is demonstrated by processing a model of The Maidens Tower.

Dağıtık simülasyonda eğitim, eğitim amaçlarını karşılamak maksadıyla genellikle dikkatlice oluşturulmuş ve tasarlanmış simülasyon senaryolarını içermektedir. Simülasyon senaryoları (diğer bir deyişle federasyon senaryoları), Federasyon Geliştirme ve Koşturma Prosesi’nde belirtilen federasyon tasarımı ve geliştirilmesi için önemli bir rol oynamakta ve aynı zamanda simülasyon senaryoları, dağıtık simülasyon alanında bir simülasyonun geliştirilmesinin başlangıcından (analiz ve tasarım) icrasına kadar tüm basamaklarında kullanılmaktadırlar. Dağıtık simülasyonda senaryoların böylesine yoğun kullanımı senaryo yönetimini zorunlu kılmaktadır. Dağıtık bir simülasyonda senaryo yönetimi; senaryonun geliştirilmesi, senaryonun yüklenmesi, senaryonun dağıtımı, olay enjektesi ve dağıtık eğitimde senaryoya bağımlı veri toplanması aktivitelerini içermektedir. Bu makale simülasyon senaryolarının temel kavramlarını açıklamakta, bir senaryo nesne modeli tanıtmakta ve pratik açıdan dağıtık bir simülasyonda ki temel senaryo yönetim aktivitelerini tartışmaktadır. Bu makale aynı zamanda senaryo yönetim aktivitelerini açıklamak için makale boyunca dağıtılmış bir şekilde gerçek bir deniz dağıtık etkileşimli simülasyon örneği sunmaktadır.

Dual phase steel has become an important engineering material to be used in structural and automotive applications due to its good combination of strength, ductility, and formability. In this study, hardenability of a low carbon and microalloyed steel was investigated by using the standard Jominy End Quench Test at four different quenching temperatures. Three steel specimens were quenched from the intercritical region at 737°C, 754°C, and 779°C separately, whereas one of them was tested at 900°C, in the fully austenitic region. After finishing the Jominy test, metallographic examination of the samples was carried out to see the variation in the microstructure through the length of the steel. And also, hardness measurements were made through the length of the samples. Results brought out that there was a strong decrease in the hardness of the tested samples after a depth of 5 mm from the quenched end.

In this paper, the microstructural and mechanical characterizations of a low carbon and micro-alloyed steel are presented. A number of heat treatments, intercritical treatment at three different temperatures, annealing, normalizing and full martensite transformation were applied to the steel to investigate the effect of microstructure on the steel’s mechanical properties. After these heat treatment procedures, microstructural and mechanical characterizations of the steel were carried out. Experimental results showed that increasing the martensite volume fraction in the steel microstructure by intercritical heat treatment increased the strength and hardness of the steel significantly.

The evolution of simulations and models during their operational use is inevitable. Constant change in technology and user requirements is the core reason. It comes up with aging and erosion of the software systems. Thus, in time, assets are started to be categorized as legacy. Software modernization has been introduced as the methodology for comprehending and transforming legacy software systems. Basically inspired by MDE, model-driven reverse engineering (MDRE) is proposed as the major approach to tackle knowledge extraction from available assets. Then canonical model transformations and forward engineering MDE practices are promoted for transforming legacy software. The Object Management Group (OMG) promoted architecture-driven modernization (ADM) as the process of understanding and transformation of existing software assets with model-driven principles that have been supported by various metamodels, tools, and languages. This chapter introduces simulation evolution and modernization. It presents and adopts the software modernization approaches, particularly ADM, for simulation modernization. After providing a background on tools, methods, and approaches that have been proposed for software modernization, a recent research effort is revealed that adopts and extends ADM, particularly the knowledge discovery metamodel (KDM), for simulation modernization.

Implementation can be introduced as one of the important steps of simulation engineering in which all the concepts and ideas, abstracted as models, are transformed to an executable form. MDE had a major effect on the practices of this step. Models became the major artifacts for implementation. MDE proposed that model development and code generation replace the traditional coding practices. This also disrupted and changed the other major implementation practices like static code analysis, integration, and testing. As models are regarded as the major artifacts, the model development is pronounced as the major activity. Guidelines have been developed for increasing the readability and maintainability of the simulation models and the efficiency and performance of the generated code. Along with them, methods and techniques have been developed for model checking and repair. Advancements in model-to-text transformation enabled effective and flexible code generation. Integration requirements could then be attacked by retargeting the code generator for particular platforms. In the same vein, model-based testing (MBT) introduced generation of executable test cases from a model. This chapter explains the activities of implementation that have been changing with introduction of MDE. These activities include model development, model checking, code generation and integration, and testing. These activities are first explained and introduced with examples from an off-the-shelf modeling and simulation environment, and then a recent methodology research on that particular activity is presented.

This chapter presents a practical approach to the design of federate architectures (i.e., simulation member design) for the simulation developers by applying a well-known architectural style, layered architecture. Adopting layered architecture for an HLA-based simulation provides a clear separation of the following concerns: the user interface, where the user can be a human or an external system such as a GIS server, the simulation logic, and the HLA-specific communication. Thus, the layered simulation architecture allows the simulation developers to focus on each concern separately and gives them the freedom to implement each layer in a different programming language and to encapsulate the tedious implementation details of the HLA federate interface specification. Moreover, this chapter introduces a wrapper for the current HLA run-time infrastructure and gives an account of the suggested implementation practices through a case study.

The objective of this chapter is to introduce the fundamental concepts, principles and processes of Model Driven Engineering (MDE). The role of MDE for code generation in simulation software engineering, interoperability, model replicability and computational reproducibility are discussed. Different modeling levels and operations such as refactoring, refinement and transformation are examined to outline various MDE use cases in simulation software engineering.

This chapter introduces the concept of federation (simulation environment) architecture. For rigorous federation design, we need more than lollipop diagrams. In this regard, first, we outline what federation architecture means and then show how to formalize a federation architecture using metamodeling, so that a federation architecture can be put into a machine processable form, thereby enabling tool support for the code generation and the early verification of the federation architectures. To this end, we present a realized metamodel, called Federation Architecture Metamodel (FAMM), for describing the architecture of a HLA compliant federation. We also discuss the verification techniques for federation architectures. Chapter concludes with a case study detailing the federation architecture modeling.

ASME International Mechanical Engineering Congress and Exposition (IMECE2015), NOV 13-19, 2015, Houston, TX, ASME, Haptic interfaces require lightweight, small actuators with high force capability and low friction. In this paper, based on the structure of conventional shear mode disc and drum type MR fluid dampers, a lightweight continuous rotary MR damper working in valve mode is designed for haptic interfaces. The proposed design is compared to shear mode disc-type and drum-type designs with similar torque-to mass ratio via computer simulations. Mathematical models for the resistant torques of both the shear mode and the valve mode are derived. Subsequently, the finite element analysis of electromagnetic circuit calculations was carried out by FEMM software to perform an optimization of the dimensions of the parts such as gap size and thickness. It is shown that the proposed continuous rotary valve mode MR damper is a fine candidate that meets the requirements of haptic interfaces.

This paper discusses the main issues involved in developing a high level architecture (HLA)-based distributed simulation while presenting an application called Naval Surface Tactical Maneuvering Simulation System (NSTMSS), which is intended to serve as a testbed for HLA and distributed interactive simulation (DIS) research. NSTMSS provides a networked virtual environment (NVE) for naval surface actions in which new formations can be evaluated and tested and present ones can be practiced and analyzed. This paper also describes a development lifecycle for HLA-based distributed interactive simulations and reflects best practices.

Haptic devices mimic force or torque responses of physical systems. In active devices, the synthetic responses are usually produced by DC motors, due to their wide range availability and ease of control. On the other hand, simulating rigid collisions require large motors, at the expense of size and weight, or gearboxes at the expense of transparency. Viscosity of magneto-rheological fluids (MRF) increases, up to the point of becoming a viscoelastic solid, when they are subjected to a magnetic field. Due to this property, they are used in adjustable dampers, where the damping force is controlled by varying the intensity of the magnetic field via an electromagnet. The use of MRF technology in passive or semi-active haptic devices is an attractive research area, in which, a number of damper designs have been proposed over the last decade. This paper investigates a linear MRF damper for haptic finger grasping applications. The damper incorporates an orifice area which is affected by a position controlled permanent magnet. Proximity of the permanent magnet to the orifice area manipulates the viscosity of the MRF; hence changes the reaction force of the damper.

Scenario development starts with capturing scenarios from the users and leads to the design and the development of the simulation environment to execute these scenarios. This paper proposes a scenario development process adopting a Model-Driven Engineering (MDE) perspective. It takes scenario development and the use of scenarios in simulation environment development put forth in IEEE Recommended Practice for Distributed Simulation Engineering and Execution Process (DSEEP) as a starting point. It then constructs a basic vocabulary including the definitions of operational, conceptual, and executable scenarios. Following MDE principles, scenario development is viewed as a series of model transformations. Operational scenarios, mostly defined in a natural language, are first transformed into conceptual scenarios, which conform to a formal metamodel. Then conceptual scenarios can be transformed into executable scenarios specified using a specific scenario definition language. Furthermore, it is also possible to generate the constructs of simulation environment design and development using model transformations. In this regard, a conceptual scenario metamodel is proposed adopting the Base Object Model metamodel as an example. Then this metamodel is used to present the proposed process with a sample operational scenario and conceptual scenario excerpts. Samples are shown how model transformation can be employed for developing a Federation Object Model and an executable scenario file.