4,715 research outputs found

    Biologically inspired learning system

    Get PDF
    Learning Systems used on robots require either a-priori knowledge in the form of models, rules of thumb or databases or require that robot to physically execute multitudes of trial solutions. The first requirement limits the robot’s ability to operate in unstructured changing environments, and the second limits the robot’s service life and resources. In this research a generalized approach to learning was developed through a series of algorithms that can be used for construction of behaviors that are able to cope with unstructured environments through adaptation of both internal parameters and system structure as a result of a goal based supervisory mechanism. Four main learning algorithms have been developed, along with a goal directed random exploration routine. These algorithms all use the concept of learning from a recent memory in order to save the robot/agent from having to exhaustively execute all trial solutions. The first algorithm is a reactive online learning algorithm that uses a supervised learning to find the sensor/action combinations that promote realization of a preprogrammed goal. It produces a feed forward neural network controller that is used to control the robot. The second algorithm is similar to first in that it uses a supervised learning strategy, but it produces a neural network that considers past values, thus providing a non-reactive solution. The third algorithm is a departure from the first two in that uses a non-supervised learning technique to learn the best actions for each situation the robot encounters. The last algorithm builds a graph of the situations encountered by agent/robot in order to learn to associate the best actions with sensor inputs. It uses an unsupervised learning approach based on shortest paths to a goal situation in the graph in order to generate a non-reactive feed forward neural network. Test results were good, the first and third algorithms were tested in a formation maneuvering task in both simulation and onboard mobile robots, while the second and fourth were tested simulation

    Sustainability in design: now! Challenges and opportunities for design research, education and practice in the XXI century

    Get PDF
    Copyright @ 2010 Greenleaf PublicationsLeNS project funded by the Asia Link Programme, EuropeAid, European Commission

    ANALYZING THE EFFECT OF POLARIZATION IN IMAGING

    Get PDF
    Light as the natural element for our life can be characterized by its intensity, wavelength and polarization. The polarization is general characteristic of wave (light, gravitational wave, sound wave etc.) that have the information of their oscillations as well as the reflecting object. Polarization of light could not be viewed naturally by our naked human eyes due to the limitation of capabilities of capturing light on a muscle known as the ciliary muscle. Nowadays, in the computer vision, the polarization is used to determine image segmentation, object and texture recognition. Moreover, in the medical field, polarization is used to allow better the diagnose of skin texture and lesion. This project uses digital image processing technique to analyze the effect of polarization in imaging, which focuses on identifying the textures or patterns of an object. In the polarization on human skin’s imaging, this analysis technique is developed to classify and determine the texture of human skin based on the different races background with the aid of polarized light as well to distinguish between the texture of normal skin and skin lesion

    Historic Look on Color Theory

    Get PDF
    The science of color is called chromatics, colorimetry, or color science. This field of science includes the perception of color by the human eye, origin of colors, art theory, therapy, the psychics of electromagnetic radiation, and effects on the brain (Azeemi). Experts throughout time have desired to decipher the composition of color to explain how and why humans are able to see colors in order to use them in numerous disciplines; from scientific to artistic. While color has been studied since ancient times, the technical workings and the modern understandings of color theory are difficult to comprehend, and one wishes to make the science more palatable. These studies have been a global pursuit. However, many important discoveries and scholars were lost over time, or inaccurately credited. The following paper takes on the historic look on color science to examine how the understanding of color has evolved over time from ancient studies until the early 19th century while unearthing uncredited experts that are not immediately recognized in modern discussion on the subject. Some experts, like Ibn al-Haytham, have been forgotten throughout time while others have been overly credited (O’Connor). At first color is defined and how colors interact with each other is explained. Secondary research and criticism of color science history is used to compare, and dispute generally accepted, ideas of color theory that were discovered until the 19th century (Popova). The purpose is to give the reader a comprehensive understanding of color science, the historical evolution of the field and expose forgotten contributors

    Upper primary school students’ scientific and socio-scientific thinking: A case study investigating epistemic challenges in year-six inquiry science lessons

    Get PDF
    Science education in schools has moved from the learning of scientific facts to investigating the impact that science has on students’ lives; providing students with an understanding of how they relate to, and affect, their environment. This shift is evident in many countries’ curricula (e.g. Australian National Curriculum). One example of this is the requirement for students to consider issues related to ‘sustainability’; to consider scientific facts and to consider themselves as both part of the problem and part of the solution. Socio-scientific issues are ill-structured; that is, they may have many viable alternative solutions and it can be difficult to know when a satisfactory solution has been reached. Solving socio-scientific problems involves the use of knowledge learnt in different contexts, including scientific knowledge and experiential knowledge. This study seeks to gain a better understanding of how and when year 6 primary school students (aged 10 to 12 years) activate prior knowledge while considering sustainability issues. The study sought to vary the context in which students were set sustainability problems. Using a ‘knowledge in pieces’ theoretical framework, which attunes to changes in context, the study investigates conditions that may promote appropriate knowledge activations. Based on a case study methodology, the research employs epistemic interviewing techniques coupled with close participant observations to gain a better, more nuanced understanding of the processes involved when year-six primary school students consider issues about sustainability. The thesis reports on three empirical episodes during which different aspects of context were varied; the problem context, the knowledge context and the physical context. Data was analysed using inductive thematic analysis and the results were considered alongside existing pedagogical approaches. The results showed that the variation of all three contextual elements led to variations in the manner in which the students solved the sustainability problems. It was observed that epistemic prompts helped the participants to make progress towards viable solutions. These epistemic prompts came from the facilitator of learning, from other students, and from the activities in which the students were engaged. When embarking on a learning program that involves socio-scientific issues, facilitators of learning can benefit from recognising that the nature of these issues will require students to integrate both taught knowledge and everyday experiences. Students may activate conflicting knowledge resources that lead to confusing results. It is at these points that epistemic challenges (challenging the students to consider their knowledge and to justify that knowledge) can prove beneficial in helping the students sort out their own solutions to these complex issues

    The evaluation of relationship mapping as a tool for understanding the experience of change

    Get PDF
    The research for this dissertation was conducted at the Western Cape site of a national manufacturing organisation in the food and beverages industry. The study set out to attain two primary goals. The first was to examine the effectiveness of relationship mapping (a method for graphically depicting mental models) as a tool for exploring the participants' experience of, and evaluation of 'planned organisational change'. The second goal was to investigate the possible impact of relationship mapping on those using the method. Research results for both of these goals were examined through three 'lenses' or frames of analysis, 'empowerment', 'communication', and 'understanding the change'. These frames of analysis were derived from reviewed literature and interaction with the organisation. Incorporated into the design was an analysis of group processes, as an additional check on the impact of the relationship mapping procedure. The study assessed the above goals across four, hierarchically-divided organisational levels, with a total of 56 participants. A classical control group design was used, incorporating qualitative and quantitative methods. Control group participants underwent in-depth interviews, semi-structured focus group discussions and a group process scale (assessing group interaction). In addition to these, the experimental groups underwent relationship mapping, use of the group process scale, and a post relationship mapping questionnaire. Thematic and statistical analyses were used for the examination of qualitative and quantitative results, respectively. Although causality cannot be inferred with certainty, results indicate that these experimental groups paid increased attention to inter-relationships, questioning and problem solving, and the production of new information. Participants recognised that relationship mapping impacted on their sense of 'empowerment' by allowing for participation, facilitating thinking, and provoking personal realisations. Relationship mapping was seen as altering participant perception of communication and improving their understanding of the change
    • …
    corecore