A virtual reality collaborative planning simulator and its method for three machines in a fully mechanized coal mining face

The existing automatic control program and its parameters for three machines in a fully mechanized Coal Mining face are static and simplex and are therefore inadequate for satisfying the complex and dynamic environment of underground coal mines. To overcome this problem, a collaborative mathematical model is established that includes the effects of a dynamic environment. A virtual reality collaborative planning simulator with methods for the three machines is also proposed based on a multi-agent system. According to the dynamic characteristics of the environment, equipment, and technologies, a fully mechanized Unity3D simulator (FMUnitySim) is designed in terms of multiple factors and multiple dimensions. The factors affecting the coordinated operation of the three machines are analyzed and modeled. The communication modes, coordination, and redundant sensing process among multiple agents, which include the shearer agent and the scraper conveyor agent, are also investigated in detail. Using this system, the key parameters of the three machines can be planned and adjusted online to design and distinctly observe the corresponding collaborative simulations of coordinated operation with multiple perspectives and in real time. Tests of different maximum shearer haulage speeds for regular or reverse transporting coal are designed; their key parameters, including the average shearer haulage speed, average follower distance, and average scraper conveyor load, are planned and simulated using FMUnitySim. The optimal parameter combination is obtained by analyzing and comparing the simulation results. The proposed FMUnitySim offers an effective means and theoretical basis for the rapid planning and safe automatic production of a fully mechanized Coal Mining face

Predicting the valence of a scene from observers’ eye movements

Multimedia analysis benefits from understanding the emotional content of a scene in a variety of tasks such as video genre classification and content-based image retrieval. Recently, there has been an increasing interest in applying human bio-signals, particularly eye movements, to recognize the emotional gist of a scene such as its valence. In order to determine the emotional category of images using eye movements, the existing methods often learn a classifier using several features that are extracted from eye movements. Although it has been shown that eye movement is potentially useful for recognition of scene valence, the contribution of each feature is not well-studied. To address the issue, we study the contribution of features extracted from eye movements in the classification of images into pleasant, neutral, and unpleasant categories. We assess ten features and their fusion. The features are histogram of saccade orientation, histogram of saccade slope, histogram of saccade length, histogram of saccade duration, histogram of saccade velocity, histogram of fixation duration, fixation histogram, top-ten salient coordinates, and saliency map. We utilize machine learning approach to analyze the performance of features by learning a support vector machine and exploiting various feature fusion schemes. The experiments reveal that ‘saliency map’, ‘fixation histogram’, ‘histogram of fixation duration’, and ‘histogram of saccade slope’ are the most contributing features. The selected features signify the influence of fixation information and angular behavior of eye movements in the recognition of the valence of images

Finite Element Analysis of the Effect of Low-Speed Rear End Collisions on the Medial Meniscus

Low-speed, rear end vehicle collisions can inflict soft tissue damage to the passenger’s knees, especially the medial meniscus, which has been previously unexplained in published literature. It is difficult to determine if factors such as age or other injury was the primary cause of the injury or if the accident acutely caused the meniscal tear. Rear end collisions may produce a combination of compressive loading and torque about the knee that will injure the medial meniscus during the initial impact and the rebound phase. The purpose of this study is to determine if it is possible for rear end low-speed collisions to tear the medial meniscus when the knee had no significant contact with the interior of the vehicle. A three-dimensional finite element model of the knee was used to determine the effect of various loads and torques imposed on the knee using the software FEBio. Compressive loading, knee flexion, axial torque, and varus torque were applied to the knee through the femur, and the stress and strain within the medial meniscus were determined. It was found that increased knee flexion along with compressive loading will increase the stress observed as compared to the knee in the neutral position. Axial torque up to 24 Nm and varus torque will both increase the stress observed in the meniscus. In a collision, if the knee experiences any type of axial or varus torque coupled with a compressive force of 670 N or more, there is a possibility that the medial meniscus will be torn. It was also found that the areas of maximum stress occur along the inner edge of the meniscus and are found primarily in the mid-body and posterior horn. While there are several inherent limitations of the current model, the results of the simulations show that several loading patterns can stress the medial meniscus to failure, especially if it was in a weakened state due to mechanical trauma or age

Enhancing experiential learning via virtual environments

Research indicates Virtual Reality (VR) is delivering on it's promised potential to provide enhanced training and education outcomes. A significant research project, at the University of Queensland, has constructed a number of virtual contexts in which the phenomena experienced by patients who have psychosis are reproduced for use in psychiatry education. Symptoms of psychosis reproduced include delusions, hallucinations and thought disorder. The new software enables psychiatry students to experience the inner world of a patient with psychosis. Lecturers in psychiatry report VR has the potential to enhance student's abilities to actually 'feel' the types of emotions and physiological reactions a hallucination precipitates in a patient. The current work of the project and stages of software development will be demonstrated. The virtual environments provide a new method of delivering experiential learning opportunities to higher education classrooms

Minimum technical requirements and evaluating effectiveness of teleradiology

Teleradiology, the electronic transmission of radiological images for the purposes of interpretation and consultation, has successfully entered routine health services. It is, therefore, currently one of the single largest applications of telemedicine. This technology is predicted to play a significant role in improving service access to rural and remote areas. However, teleradiology services are currently characterized by a compromise between expense and quality of digital images. This paper reviews minimum equipment requirements and the technical issues and limits that are experienced when utilizing current teleradiological technology. Categories of service evaluation, including measures of user satisfaction, clinical outcome and financial benefit, are discussed in relation to facilitating a radiology service of the highest quality possible

Internet social support for children and adolescents

The Internet is becoming increasingly commonplace in the lives of many young people in Western societies. The numbers of children and adolescents obtaining friendship and support from the Internet are expected to grow substantially. Young people generally require social support to be able to cope well with stress events. Because young people are using information technology at an ever-increasing rate it is important to gain a better understanding of their social support experiences within this technological context. Growing up with a child who has special needs can have adverse consequences for siblings. It can undermine their emotional and psychological wellbeing and social functioning. We have studied the online conversations of young individuals who participated in Sibkids, an online support group for children who have a sibling with special needs

Psychology Student Opinion of Virtual Reality as a Tool to Educate About Schizophrenia

VR techniques are being increasingly used in training and education generally (MacPherson & Keppell, 1998; Romano & Brna, 2001) and specifically within healthcare education (Riva & Gamberini, 2000). A project at the University of Queensland constructed a number of three-dimensional demonstration models of the phenomena seen in schizophrenia. Reproduced symptoms of schizophrenia included delusions, hallucinations and thought disorder. Auditory hallucinations were also included, consisting of voices ranging from muffled whispers to a cacophony of voices