Praise for the Third Edition: "This is one of the best books available. Its excellent organizational structure allows quick reference to specific models and its clear presentation . . . solidifies the understanding of the concepts being presented."IIE Transactions on Operations EngineeringThoroughly revised and expanded to reflect the latest developments in the field, Fundamentals of Queueing Theory, Fourth Edition continues to present the basic statistical principles that are necessary to analyze the probabilistic nature of queues. Rather than presenting a narrow focus on the subject, this update illustrates the wide-reaching, fundamental concepts in queueing theory and its applications to diverse areas such as computer science, engineering, business, and operations research.This update takes a numerical approach to understanding and making probable estimations relating to queues, with a comprehensive outline of simple and more advanced queueing models. Newly featured topics of the Fourth Edition include:Retrial queuesApproximations for queueing networksNumerical inversion of transformsDetermining the appropriate number of servers to balance quality and cost of serviceEach chapter provides a self-contained presentation of key concepts and formulae, allowing readers to work with each section independently, while a summary table at the end of the book outlines the types of queues that have been discussed and their results. In addition, two new appendices have been added, discussing transforms and generating functions as well as the fundamentals of differential and difference equations. New examples are now included along with problems that incorporate QtsPlus software, which is freely available via the book's related Web site.With its accessible style and wealth of real-world examples, Fundamentals of Queueing Theory, Fourth Edition is an ideal book for courses on queueing theory at the upper-undergraduate and graduate levels. It is also a valuable resource for researchers and practitioners who analyze congestion in the fields of telecommunications, transportation, aviation, and management science.

Fundamentals of Queueing Theory

Since the first time the term "Virtual Reality" (VR) has been used back in the 60s, VR has evolved in different manners becoming more and more similar to the real world. Two different kinds of VR can be identified: non-immersive and immersive. The former is a computer-based environment that can simulate places in the real or imagined worlds; the latter takes the idea even further by giving the perception of being physically present in the non-physical world. While non-immersive VR can be based on a standard computer, immersive VR is still evolving as the needed devices are becoming more user friendly and economically accessible. In the past, there was a major difficulty about using equipment such as a helmet with goggles, while now new devices are being developed to make usability better for the user. VR, which is based on three basic principles: Immersion, Interaction, and User involvement with the environment and narrative, offers a very high potential in education by making learning more motivating and engaging. Up to now, the use of immersive-VR in educational games has been limited due to high prices of the devices and their limited usability. Now new tools like the commercial "Oculus Rift", make it possible to access immersive-VR in lots of educational situations. This paper reports a survey on the scientific literature on the advantages and potentials in the use of Immersive Virtual Reality in Education in the last two years (2013-14). It shows how VR in general, and immersive VR in particular, has been used mostly for adult training in special situations or for university students. It then focuses on the possible advantages and drawbacks of its use in education with reference to different classes of users like children and some kinds of cognitive disabilities (with particular reference to the Down syndrome). It concludes outlining strategies that could be carried out to verify these ideas.

A literature review on immersive virtual reality in education: state of the art and perspectives

Communication in the Age of Virtual Reality.

/pdf/virtual-reality-and-gamification-in-marketing-higher-4s6tuao7fe.pdf

Virtual reality and gamification in marketing higher education: a review and research agenda

Skill training in the medical device manufacturing industry is essential to optimize and expedite the efficiency level of new workers. This process, however, gives rise to many underlying issues such as contamination and safety risks, long training period, high skill and experience requirements of operators, and greater training costs. In this paper, we proposed and evaluated a novel virtual reality (VR) training system for the assembly of hybrid medical devices. The proposed system, which is an integration of Artificial Intelligence (AI), VR and gaming concepts, is self-adaptive and autonomous. This enables the training to take place in a virtual workcell environment without the supervision of a physical trainer. In this system, a sequential framework is proposed and utilized to enhance the training through its various “game” levels of familiarity-building processes. A type of hybrid medical device: carbon nanotubes-polydimethylsiloxane (CNT-PDMS) based artificial trachea prosthesis is used as a case study in this paper to demonstrate the effectiveness of the proposed system. Evaluation results with quantitative and qualitative comparisons demonstrated that our proposed training method has significant advantages over common VR training and conventional training methods. The proposed system has addressed the underlying training issues for hybrid medical device assembly by providing trainees with effective, efficient, risk-free and low cost training.

Virtual reality training for assembly of hybrid medical devices

The cave automatic virtual environment (CAVE) system is one of the most fully immersive systems for virtual reality environments. By providing users with realistic perception and immersive experience, CAVE systems have been widely used in many fields, including military, education, health care, entertainment, design, and others. In this paper, we focus on the design applications in the CAVE. The design applications involve many interactions between the user and the CAVE. However, the conventional interaction tool, the wand, cannot provide fast and convenient interactions. In this paper, we propose vDesign, a CAVE-based virtual design environment using hand interactions. The hand interactions in vDesign are classified into menu navigation and object manipulations. For menu navigation, we define two interactions: activating the main menu and selecting a menu item. For object manipulations, we define three interactions: moving, rotating, and scaling an object. By using the proposed hand interactions, we develop the functions of image segmentation and image composition in vDesign. With the image segmentation function, the designer can select and cut the interested objects from different images. With the image composition function, the designer can manipulate the segmented objects and combine them as a composite image. We implemented the vDesign prototype in CAVE and conducted experiments to evaluate the interaction performance in terms of manipulation time and distortion. The experimental results demonstrated that the proposed hand interactions can provide faster and more accurate interactions compared to the traditional wand interactions.

vDesign: a CAVE-based virtual design environment using hand interactions

The Cave Automatic Virtual Environment (CAVE) is a fully immersive Virtual Reality (VR) system. CAVE systems have been widely used in many applications, such as architectural and industrial design, medical training and surgery plan, museums and education. However, one limitation for most of the current CAVE systems is that they are separated from the real world. The user in the CAVE is not able to sense the real world around him or her. In this paper, we propose a vConnect architecture, which aims to establish real-time bidirectional information exchange between the virtual world and the real world by utilizing the advanced technologies in cloud computing, mobile communications, wireless sensor networks, and computer vision. Specifically, we address three technical challenges in the proposed vConnect architecture. First, we propose an optimal allocation scheme for the wireless sensor networks to ensure that the data streams captured by the sensors can be delivered to the cloud servers in a reliable and prompt way. Second, we optimize the allocation of the cloud resources to ensure that the data streams sent from the clients can be processed promptly by the cloud servers at a minimal resource cost. Third, we propose to use marker-based finger interactions such that the user in the CAVE can manipulate the information in a natural and intuitive way. Fourth, we implemented a vHealth prototype, a CAVE-based real-time health monitoring system, to validate the proposed vConnect architecture. We demonstrated in the vHealth prototype that the user in the CAVE can visualize and manipulate the real-time physiological data of the patient who is being monitored, and interact with the patient.

vConnect: perceive and interact with real world from CAVE

The Cave Automatic Virtual Environment (CAVE) system is a fully immersive virtual reality system, which can provide users with a realistic experience and a large freedom of interactions. In this paper, we propose vDesign, a CAVE-based virtual design environment using finger interactions. Specifically, we focus on the function of image segmentation and composition in the vDesign system. In vDesign, the user wears a marker on each hand. The interactions of the user are triggered based on the real-time positions of the markers. We design multiple finger interactions for image segmentation and image composition. In image segmentation, the user can use the right finger to select the interested object and the left finger to select the unrelated background. Based on the user's selection, a graph-cut based image segmentation is employed to extract the interested object from the image. In image composition, the user can move, rotate, and scale the segmented objects with fingers and combine them together into a final image. We implemented the vDesign prototype and conducted experiments to compare the finger interactions and the traditional wand interactions. The experimental results demonstrated that the proposed finger interactions can provide faster and more accurate interactions compared to the traditional wand interactions.

VDESIGN: Toward image segmentation and composition in cave using finger interactions

The Cave Automatic Virtual Environment (CAVE) is a fully immersive Virtual Reality (VR) system. CAVE systems have been widely used in many applications, such as architectural and industrial design, medical training and surgical planning, museums and education. However, one limitation for most of the current CAVE systems is that they are separated from the real world. The user in the CAVE is not able to sense the real world around him or her. In this paper, we propose a vConnect architecture, which aims to establish real-time bidirectional information exchange between the virtual world and the real world. Furthermore, we propose finger interactions which enable the user in the CAVE to manipulate the information in a natural and intuitive way. We implemented a vHealth prototype, a CAVE-based real-time health monitoring system, through which we demonstrated that the user in the CAVE can visualize and manipulate the real-time physiological data of the patient who is being monitored, and interact with the patient.

Ning Zhang

Papers

vDesign: a CAVE-based virtual design environment using hand interactions

vConnect: perceive and interact with real world from CAVE

VDESIGN: Toward image segmentation and composition in cave using finger interactions

vConnect: Connect the real world to the virtual world