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The purpose of this paper is to introduce the Opencast Community, a global community of individuals, institutions, and commercial stakeholders exchanging knowledge about all matters relevant in the context of academic video and promoting projects in this context. It also gives an overview of the most prominent of these projects, Opencast Matterhorn – a community‐driven open source solution for producing, managing, and distributing academic video.

The paper will demonstrate that Opencast Matterhorn is satisfying institutional needs to manage audiovisual content more efficiently as video is becoming a significant resource in research and education. Furthermore, the paper highlights that Opencast Matterhorn as a product and as a project is open for contributions from the research community and provides an excellent environment for the integration of research results from media analysis, multimedia authoring, search technologies, and other related fields.

Opencast Matterhorn provides a scalable open source solution for universities to manage academic video. Its service‐oriented architecture makes it customizable to institutional needs and open for contributions from users as well as media research.

The paper provides an insight to the idea of Opencast, the Opencast Community, and Opencast Matterhorn – and how they will help academic institutions to better manage and exploit the full richness of educational video.

This paper aims to describe the principles underlying the successful implementation of a lecture recording service in higher education.

The paper qualitatively reviews the practices and experiences of several years of automated lecture recording at a medium-sized university in Germany.

The paper concludes that there are several principles that should be followed to successfully implement lecture recordings in higher education.

The principles described in this paper can serve as recommendations for other universities that would like to establish or optimize their own lecture recording service.

The value of the paper lies mainly in the great amount of experience in successfully running a lecture recording service on which the principles and recommendations are based.

This paper describes the development of a hybrid knowledge base system and genetic algorithms to select the optimum excavating and haulage equipment in opencast mining. The knowledge base system selects the equipment in broad categories based on the geological, technical and environmental characteristics of the mine. To further identify the make, size and number of each piece of equipment that minimizes the total cost of the operation, the problem is solved using the genetic algorithms mechanism. Results of four case studies are presented to show the validation of the developed system.

The purpose of this paper is to present a user interface for web lectures for engaging with other users while working with video based learning content. The application allows its users to ask questions about the content and to get answers from those users that currently online are more familiar with it. The filtering is based on the evaluation of past user interaction data in time‐based media.

The work is implemented as a prototype application in the context of the Opencast Matterhorn project – an open source based project for producing, managing and distributing academic video content. The application compares users viewing behavior and allows communication with others that are good candidates to answer questions.

Different filtering approaches for identifying suitable candidates are being discussed that foster past interactions in time‐based media.

The paper shows that web lectures can benefit from user awareness ideas and presents examples of how learners can benefit from the knowledge of other users who are working with the same video based content.

User awareness has become an important feature in today's Web 2.0 experience. The paper discusses different user awareness models and explains how they can be adapted to time‐based video content. The presented work is available as a plug‐in for the Opencast Matterhorn project.

Improving the use of annotations in lecture recordings.

Requirements analysis with scenario based design (SBD) on focus groups.

These seven points have been extracted from the feedback of the focus groups: (1) Control of the annotation feature (turn on/turn off). (2) An option to decide who is able to see their comments (groups, lecturer, friends). (3) An easy and paper-like experience in creating a comment. (4) An option to discuss comments. (5) An option to import already existing comments. (6) Color-coding of the different types of comments. (7) An option to print their annotations within the context of the recording.

The study was performed to improve the open-source lecture recording system Opencast Matterhorn.

Annotations can help to enable the students that use lecture recordings to move from a passive watching to an active viewing and reflecting.

Utilization of off‐highway vehicles forms an essential part of UK industry's efforts to augment the productivity of plant operations and reduce production costs. However, uninterrupted utilization of plant and equipment is requisite to reaping the maximum benefit of mechanization; one particular problem being plant breakdown duration and its impact upon process productivity. Predicting the duration of plant downtime would enable plant managers to develop suitable contingency plans to reduce the impact of downtime. This paper presents a stochastic mathematical modelling methodology (more specifically, probability density function of random numbers) which predicts the probable magnitude of ‘the next’ breakdown, in terms of duration for tracked hydraulic excavators. A random sample of 33 machines was obtained from opencast mining contractors, containing 1070 observations of machine breakdown duration. Utilization of the random numbers technique will engender improved maintenance practice by providing a practical methodology for planning, scheduling and controlling future plant resource requirements. The paper concludes with direction for future research which aims to: extend the model's application to cover other industrial settings and plant items; to predict the time at which breakdown will occur (vis‐à‐vis the duration of breakdown); and apply the random numbers modelling to individual machine compartments.

Notes that the real test of maintenance stratagem success (or failure in financial terms) can only be resolved when a comparison of machine maintenance costs can be made to some benchmark standard. Presents a comparative study between two models developed to predict the average hourly maintenance cost of tracked hydraulic excavators operating in the UK opencast mining industry. The models use the conventional statistical technique multiple regression, and artificial neural networks. Performance analysis using mean percentage error, mean absolute percentage error and percentage cost accuracy intervals was conducted. Results reveal that both models performed well, having low mean absolute percentage error values (less than 5 percent) indicating that predictor variables were reliable inputs for modelling average hourly maintenance cost. Overall, the neural network model performed slightly better as it was able to predict up to 95 percent of cost observations to within ≤q £5. Moreover, summary statistical analysis of residual values highlighted that predicted values using the neural network model are less subject to variance than the multiple regression model.

It is recognised by valuers that the effects of coal mining on land in Great Britain can have a significant impact oon the value of a particular site when it is being considered for potential surface development purposes. In this respect a great many buildings are erected successfully each year within mining areas after the effects of mining have been taken into account. If, however, the adverse effects of mining are not recognised and during the site development stage a problem suddenly appears, it is obvious that this may lead to considerable increases in cost and/or delay to the proposed development for which the land was originally purchased. Obviously with sufficient prior appreciation and investigation of the mining position such situations could be avoided. It is with this in mind that the following paper aims to indicate in broad outline, but in such detail relevant to the valuer, some of the major influences of coal mining which require to be recognised and equated in monetary terms when assessing potential site values for development purposes in mining areas.

Geophysical methods are widely applied for the prognostication of natural and technogeneous risks. Especially effective is their application in the sphere of engineering geology and the ore exploration industry. The effectiveness of geophysical methods is convincingly illustrated by the concrete results obtained in studies, performed to solve specific problems. This paper presents an overview of methods and studies in the field of natural and technogeneous risks by the application of geophysical surveying. In a case study focusing on opencast coal exploration in the area of Maritza‐East, the usefulness of geophysical methods in mapping the hard rock inclusions in the overburden of the lignite mines is outlined. The possibilities of using such technologies for guiding the process and the reduction of technogeneous risks during exploration are outlined.