Analysis of radial segregation of granular mixtures in a rotating drum

This paper considers the segregation of a granular mixture in a rotating drum. Extending a recent kinematic model for grain transport on sandpile surfaces to the case of rotating drums, an analysis is presented for radial segregation in the rolling regime, where a thin layer is avalanching down while the rest of the material follows rigid body rotation. We argue that segregation is driven not just by differences in the angle of repose of the species, as has been assumed in earlier investigations, but also by differences in the size and surface properties of the grains. The cases of grains differing only in size (slightly or widely) and only in surface properties are considered, and the predictions are in qualitative agreement with observations. The model yields results inconsistent with the assumptions for more general cases, and we speculate on how this may be corrected.Comment: 12 pages inclusive of 10 PostScript (*.eps) figures, uses svjour, psfrag and graphicx. Submitted for publication to Euro. Phys. J.

Unlocking Complexity: The Importance of Idealisation in Simulation Modelling

Idealisation is the process of finding simple representations of the real-world whilst conceptualising a model. There are three ways to limit complication in a model of a complex real-world: by focussing the scope of the modelling process onto a clearly defined issue; by idealising elements of the real-world during model conceptualisation; and by simplifying the implemented simulation program. Careful idealisation has the greatest potential for increasing model tractability whilst generating insights during the model design process. The Forest Land Oriented Resource Envisioning System (FLORES) project deals with social forest landscapes which are highly complex. Benefits of idealisation are demonstrated using six examples from this modelling work. These examples encompass issues dealing with land tenure, forest management, economic values, social diversity, communication and collaboration. Each example illustrates a different method to achieve an idealisation which yields insights relevant for policy players. A number of lessons about idealisation are also identified: (1) sometimes it is only possible to recognise what is key by omitting it; (2) an effective idealisation is not just achieved by leaving things out, or adding them back in; it can also be achieved by restructuring the representation; (3) it is important challenge the use of different units where consistency is possible; (4) it is easier to keep a simple model simple, than to make simple modifications to a large model. Similarly, it is easier to generate insights with a simple concept for a sub-model than with a simple modification to an existing model; and (5) even the most useful idealisations may have a limited shelf-life

Assessment of Use and Utilisation of Library Resources, Services and Facilities by Law Students at Kristu Jayanti College of Law, Bangalore

The main aim of this study is to investigate the use of library resources, services and facilities by law students; it is mainly focused on use, purpose and satisfaction level with the library collection, services and facilities. This study used survey method to collect data. A well-structured questionnaire was distributed. Out of 110, only 91(83%) questionnaires were collected and select for analysis. Result revelled that library services and collection were satisfied further findings show users are not aware about Journals and E-Resources. So, study recommends that should conduct information literacy programme to promote awareness use of library services and use of resource

Healthy Forests: Sound Economics, Social Justice

Concern over the management of the world's forests is becoming a hot topic, and no area is under heavier scrutiny than the tropical forests. The current rate of deforestation, especially in light of the enormous number of species these forests contain, is the primary cause for this concern. Despite this ominous trend, much can be done to protect and sustain these incredibly valuable resources

Bringing Shared Visions to Life

This book is about encouraging people to share visions and helping them to progress from these visions to take appropriate actions that will help realise their vision. The choice of appropriate actions is a key aspect of this book, and we dwell on some ways to ensure that chosen actions are effective ways to make progress in realizing a vision

Modelling Interactions amongst People and Forest Resources at the Landscape Scale

FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological, economic and social issues at the landscape scale. This piece describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the lessons learned

A Model to Help People to Realize Sustainable Forestry Futures

People usually know how they want their situation to change to secure a better future – but they do not always know how to change their situation. Initiatives intended to secure a better future do not always work as intended, and may have unintended side effects. Computer models can help advocates explore consequences of proposed initiatives, so they can make informed selections of alternatives, secure in the knowledge that consequences have been thoroughly investigated. By encouraging people to explore scenarios, models empower people to be more innovative and less dependent on technocrats. Models also enable planners to experiment with policy without risks to people or to the environment. Emerging software solves many technical limitations, but the real issue is not software, but rather the provision of a supportive framework within which people can express and experiment with ideas. FLORES, the Forest Land Oriented Resource Envisioning System, provides such a framework to stimulate interdisciplinary collaboration between researchers, practitioners and clients. Two recent workshops have demonstrated the feasibility of FLORES, one of which provides the subject matter for a forthcoming issue of Small-scale Forest Economics, Management and Policy. However, FLORES is not about software; it is about providing the means to explore the consequences of alternative scenarios. Ultimately, FLORES is not a physical package, but an association of users and the interactions they have amongst themselves, and with the people involved in policy-making. By promoting this emerging network and providing technical support we encourage more people, especially those from developing countries, to influence the development of FLORES and the issues that can be explored within it

A Taxonomy of Deep Convolutional Neural Nets for Computer Vision

Traditional architectures for solving computer vision problems and the degree of success they enjoyed have been heavily reliant on hand-crafted features. However, of late, deep learning techniques have offered a compelling alternative -- that of automatically learning problem-specific features. With this new paradigm, every problem in computer vision is now being re-examined from a deep learning perspective. Therefore, it has become important to understand what kind of deep networks are suitable for a given problem. Although general surveys of this fast-moving paradigm (i.e. deep-networks) exist, a survey specific to computer vision is missing. We specifically consider one form of deep networks widely used in computer vision - convolutional neural networks (CNNs). We start with "AlexNet" as our base CNN and then examine the broad variations proposed over time to suit different applications. We hope that our recipe-style survey will serve as a guide, particularly for novice practitioners intending to use deep-learning techniques for computer vision.Comment: Published in Frontiers in Robotics and AI (http://goo.gl/6691Bm

Transcranial Magnetic Stimulation: Design of a Stimulator and a Focused Coil for the Application of Small Animals

Transcranial magnetic stimulation (TMS) is a non-invasive, safe, effective, and food and drug administration approved treatment for major depressive disorder. TMS relies on time-varying magnetic fields to induce an electric field in the brain, resulting in depolarization or hyperpolarization of the neurons. Recently, there has been extensive research to improve the magnetic coil design, effectiveness of TMS treatment, and improvement in the computer modeling of human brains, yet little development is reported on the TMS pulse generators and coil design for small animals. TMS pulse generators, or stimulators, are the circuits which provides pulse current to drive the inductive coils (TMS coils), used to generate time-varying magnetic fields. Commercial TMS stimulators are expensive and have limitations of using standard and non-customizable coils. These stimulators do not support small inductive loads, which require high-current capabilities. Furthermore, the commercial animal coil stimulates the entire body of a mouse, as they are designed for large animals. In this paper, the authors present the design of a small sized TMS stimulator and a focused coil for the application on small animals such as mice. The proposed TMS stimulator will have the potential of handling small inductive loads enabling stimulation of specific regions within the mouse brain

Collaborative Modelling to Support Forest Management: Qualitative Systems Analysis at Lumut Mountain, Indonesia

Complex ecological and social processes in tropical forests imply that observations on any single element of the system do not provide an adequate basis for sound forest management. A collaborative modelling process engaging all relevant stakeholders led to a shared understanding of how to manage forests around Lumut Mountain, Pasir District, East Kalimantan. The model was developed by identifying forest management objectives, building a conceptual model using a causal loop diagram, and defining performance indicators. The model was then used to explore future scenarios to improve the well-being of local stakeholders while maintaining forest quality. Finally, roles needed to implement the chosen scenarios were defined and assigned to individual participants. This qualitative modelling process was found to be an effective way to assist the development of a collaborative action plan