790 resultados para Engeström, Yrjö: Perspectives on activity theory
Resumo:
Based on some constructs of the Activity Theory (Leontiev, 1978), we point to the need to develop activities that reveal the meaning of representations. We examine use of representations in teaching and propose some suggestions. Shaaron Ainsworth (1999) asserted that, in order to learn from engaging with multiple representations of scientific concepts, students need to be able to (a) understand the codes and signifiers in a representation, (b) understand the links between the representation and the target concept or process, (c) translate key features of the concept across representations and (d) know which features to emphasize in designing their own representations.
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Recently there has been a considerable interest in dynamic textures due to the explosive growth of multimedia databases. In addition, dynamic texture appears in a wide range of videos, which makes it very important in applications concerning to model physical phenomena. Thus, dynamic textures have emerged as a new field of investigation that extends the static or spatial textures to the spatio-temporal domain. In this paper, we propose a novel approach for dynamic texture segmentation based on automata theory and k-means algorithm. In this approach, a feature vector is extracted for each pixel by applying deterministic partially self-avoiding walks on three orthogonal planes of the video. Then, these feature vectors are clustered by the well-known k-means algorithm. Although the k-means algorithm has shown interesting results, it only ensures its convergence to a local minimum, which affects the final result of segmentation. In order to overcome this drawback, we compare six methods of initialization of the k-means. The experimental results have demonstrated the effectiveness of our proposed approach compared to the state-of-the-art segmentation methods.
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This research aimed for an extended knowledge and understanding of young people in stigmatized areas and their construction of group identity. With a focus on Roma youths in Konik, Montenegro, and their involvement in hip-hop we wanted to explore what this culture meant to them in relation to their context. An ethnographic approach was used in collecting the empirical data through observations, interpreting music lyrics and conducting qualitative semi-structured interviews. Five young Roma boys from Konik, all involved in hip-hop, were interviewed. Theoretical perspectives on identity, youth culture and stigmatization were central. In addition, Bourdieu’s theory regarding cultural capital was emphasized and connected to youths and hip-hop. The empirical material showed that involvement in hip-hop provided the Roma youths with a group identity that they referred to in positive terms. Contextual factors of stigmatization excluded the Roma group from the majority population and the engagement in hip-hop created a possibility for the youths to be someone. The cultural capital gained through hip-hop was not used to verify and legitimate an authentic Roma identity. It was rather a way for them to create boundaries towards the negative elements in their community.
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While it is only in recent decades that scholars have begun to reconsider and problematize Buddhist conceptions of “freedom” and “agency,” the thought traditions of Asian Buddhism have for many centuries struggled with questions related to the issue of “liberation”—along with its fundamental ontological, epistemological and ethical implications. With the development of Marxist thought in the mid to late nineteenth century, a new paradigm for thinking about freedom in relation to history, identity and social change found its way to Asia, and confronted traditional religious interpretations of freedom as well as competing Western ones. In the past century, several attempts have been made—in India, southeast Asia, China and Japan—to bring together Marxist and Buddhist worldviews, with only moderate success (both at the level of theory and practice). This paper analyzes both the possibilities and problems of a “Buddhist materialism” constructed along Marxian lines, by focusing in particular on Buddhist and Marxist conceptions of “liberation.” By utilizing the theoretical work of Japanese “radical Buddhist” Seno’o Girō, I argue that the root of the tension lies with conceptions of selfhood and agency—but that, contrary to expectations, a strong case can be made for convergence between Buddhist and Marxian perspectives on these issues, as both traditions ultimately seek a resolution of existential determination in response to alienation. Along the way, I discuss the work of Marx, Engels, Gramsci, Lukàcs, Sartre, and Richard Rorty in relation to aspects of traditional (particularly East Asian Mahāyāna) Buddhist thought.
Resumo:
Listeriosis is an emerging zoonotic infection of humans and ruminants worldwide caused by Listeria monocytogenes (LM). In both host species, CNS disease accounts for the high mortality associated with listeriosis and includes rhombencephalitis, whose neuropathology is strikingly similar in humans and ruminants. This review discusses the current knowledge about listeric encephalitis, and involved host and bacterial factors. There is an urgent need to study the molecular mechanisms of neuropathogenesis, which are poorly understood. Such studies will provide a basis for the development of new therapeutic strategies that aim to prevent LM from invading the brain and spread within the CNS.
Resumo:
Mr. Pechersky set out to examine a specific feature of the employer-employee relationship in Russian business organisations. He wanted to study to what extent the so-called "moral hazard" is being solved (if it is being solved at all), whether there is a relationship between pay and performance, and whether there is a correlation between economic theory and Russian reality. Finally, he set out to construct a model of the Russian economy that better reflects the way it actually functions than do certain other well-known models (for example models of incentive compensation, the Shapiro-Stiglitz model etc.). His report was presented to the RSS in the form of a series of manuscripts in English and Russian, and on disc, with many tables and graphs. He begins by pointing out the different examples of randomness that exist in the relationship between employee and employer. Firstly, results are frequently affected by circumstances outside the employee's control that have nothing to do with how intelligently, honestly, and diligently the employee has worked. When rewards are based on results, uncontrollable randomness in the employee's output induces randomness in their incomes. A second source of randomness involves the outside events that are beyond the control of the employee that may affect his or her ability to perform as contracted. A third source of randomness arises when the performance itself (rather than the result) is measured, and the performance evaluation procedures include random or subjective elements. Mr. Pechersky's study shows that in Russia the third source of randomness plays an important role. Moreover, he points out that employer-employee relationships in Russia are sometimes opposite to those in the West. Drawing on game theory, he characterises the Western system as follows. The two players are the principal and the agent, who are usually representative individuals. The principal hires an agent to perform a task, and the agent acquires an information advantage concerning his actions or the outside world at some point in the game, i.e. it is assumed that the employee is better informed. In Russia, on the other hand, incentive contracts are typically negotiated in situations in which the employer has the information advantage concerning outcome. Mr. Pechersky schematises it thus. Compensation (the wage) is W and consists of a base amount, plus a portion that varies with the outcome, x. So W = a + bx, where b is used to measure the intensity of the incentives provided to the employee. This means that one contract will be said to provide stronger incentives than another if it specifies a higher value for b. This is the incentive contract as it operates in the West. The key feature distinguishing the Russian example is that x is observed by the employer but is not observed by the employee. So the employer promises to pay in accordance with an incentive scheme, but since the outcome is not observable by the employee the contract cannot be enforced, and the question arises: is there any incentive for the employer to fulfil his or her promises? Mr. Pechersky considers two simple models of employer-employee relationships displaying the above type of information symmetry. In a static framework the obtained result is somewhat surprising: at the Nash equilibrium the employer pays nothing, even though his objective function contains a quadratic term reflecting negative consequences for the employer if the actual level of compensation deviates from the expectations of the employee. This can lead, for example, to labour turnover, or the expenses resulting from a bad reputation. In a dynamic framework, the conclusion can be formulated as follows: the higher the discount factor, the higher the incentive for the employer to be honest in his/her relationships with the employee. If the discount factor is taken to be a parameter reflecting the degree of (un)certainty (the higher the degree of uncertainty is, the lower is the discount factor), we can conclude that the answer to the formulated question depends on the stability of the political, social and economic situation in a country. Mr. Pechersky believes that the strength of a market system with private property lies not just in its providing the information needed to compute an efficient allocation of resources in an efficient manner. At least equally important is the manner in which it accepts individually self-interested behaviour, but then channels this behaviour in desired directions. People do not have to be cajoled, artificially induced, or forced to do their parts in a well-functioning market system. Instead, they are simply left to pursue their own objectives as they see fit. Under the right circumstances, people are led by Adam Smith's "invisible hand" of impersonal market forces to take the actions needed to achieve an efficient, co-ordinated pattern of choices. The problem is that, as Mr. Pechersky sees it, there is no reason to believe that the circumstances in Russia are right, and the invisible hand is doing its work properly. Political instability, social tension and other circumstances prevent it from doing so. Mr. Pechersky believes that the discount factor plays a crucial role in employer-employee relationships. Such relationships can be considered satisfactory from a normative point of view, only in those cases where the discount factor is sufficiently large. Unfortunately, in modern Russia the evidence points to the typical discount factor being relatively small. This fact can be explained as a manifestation of aversion to risk of economic agents. Mr. Pechersky hopes that when political stabilisation occurs, the discount factors of economic agents will increase, and the agent's behaviour will be explicable in terms of more traditional models.
Resumo:
Amalgamation is a process in which precious metals are collected by mercury. The exact way in which the mercury holds the other metals is not positively known. It is probable that a series of intermetallic compounds form. Very little work has been done so far on the theory of amalgamation.
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The aim of the paper was to get an understanding about how the profession of social work explains its relevance and legitimacy in today's Russia, to enlighten the importance of socio-political, professional and educational contexts in explaining the societal position of the social work profession in Russia. This paper begins with the analysis of the processes of legitimization, professionalization and constitution of social work in today's Russia. In addition to functionalist and critical perspectives on these three processes, in its second part the paper employs phenomenological approach looking into everyday life theory of social work that is constructed in routine work at the social service agencies. The third part of this paper talks about the issues of social services and social work with family and children in contemporary Russia.
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The article is concerned with design and use of e-learning technology to develop education qualitatively. The purpose is to develop a framework for a pedagogical evaluation of e-learning technology. The approach is that evaluation and design must be grounded in a learning theoretical approach, and it is argued that it is necessary to make a reflection of technology in relation to activities, learning principles, and a learning theory in order to qualitatively develop education. The article presents three frameworks developed on the basis of cognitivism, radical constructivism and activity theory. Finally, on the basis of the frameworks, the article discusses e-learning technology and, more specifically, design of virtual learning environments and learning objects. It is argued that e-learning technology is not pedagogically neutral, and that it is therefore necessary to focus on design of technology that explicitly supports a certain pedagogical approach. Further, it is argued that design should direct its focus away from organisation of content and towards design of activities.
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Numerous models have been formulated to describe development. Generally, these start off with a state of not-yet development or nondevelopment, and then go on to contrast this with a second state: some kind of plan or blueprint for development. As a result, the process of development is equated with a series of completed stages. Like having to climb the rungs of a ladder, one moves up and up in order to become more and more developed. The associated catching-up processes are then frequently described with phase models. ln contrast to such goal-directed perspectives on development with their links to modernization theory, social development pursues an alternative approach focusing on the empowerment and autonomy of actors, and also taking account of the structural obstacles that confront them as they shape their daily lives in the sense of learning to develop their selves. This means that development is always conceived within a twin framework of self- and other-development. Social development represents a holistic approach that is non-static and process-oriented.
Resumo:
BACKGROUND The extent to which physical performance limitations affect the ability of childhood cancer survivors to reach healthy activity levels is unknown. Therefore this study aims to describe the effect of different types of limitations on activity levels in survivors. PROCEDURE Within the Swiss Childhood Cancer Survivor Study we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. We measured healthy activity levels using international guidelines and assessed different kinds of performance limitations (visual impairment, weight and endurance problems, cardiorespiratory, musculoskeletal, and neurological problems, pain and fatigue syndromes). RESULTS The sample included 1,560 survivors (75% response rate), of whom 209 (13.5%) reported they have performance limitations. Forty-two percent of survivors with limitations reached healthy activity levels, compared to 57% of survivors without limitations. Least active were survivors with vision impairments (25% active), weight and endurance problems (27.3%), cardiorespiratory problems (36.4%), and musculoskeletal problems (43.1%). After adjusting for socio-demographic variables and type of cancer, we found that survivors with limitations were 1.4 (95%CI 1.0-2.0; P = 0.047) times more likely to be inactive. CONCLUSIONS Although many survivors with physical performance limitations maintain healthy activity levels, there is room for improvement. Adapted and targeted physical activity counseling for survivors with performance limitations might help them to raise level of activity and pursue a healthy lifestyle.
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Family offices are organisations dedicated to the management of entrepreneurial families’ private wealth. Based on agency theory, we analyse types of family offices with regard to the families’ goals and the control mechanisms used to ensure goal achievement. Family-dominant management and private client structures involve stronger emphasis on non-financial goals in single and multi-family offices than in non-family-dominant management and open client structures. Variations in family involvement, ranging from family dominance to the complete absence of family ownership and/or management, and diverse client structures justify the differential reliance on formal and informal control mechanisms.
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This investigation attempts to answer the question why more and more parents have chosen the Gymnasium for their children's secondary school education in post‐war West Germany. Based on the theory of subjective expected utility, the crucial mechanisms of parental educational decisions have been emphasized. From this perspective it is assumed that increasing educational motivation coupled with changes in the subjective evaluation of the cost–benefit of education were important conditions for an increasing participation in upper secondary schools. These were, however, in turn, the result of educational expansion. The empirical analyses for three time‐periods in the 1960s, 1970s, and 1980s confirm these assumptions to a large degree. Additionally, empirical evidence was found to suggest that in addition to the intentions of parents and the educational career of their children, structural moments of educational expansion and their own inertia played an important role in the pupils' transition from one educational level to the next. Finally, evidence was found that persistent class‐specific educational inequality stems from a constant balance in the relative cost–benefit advantages between social classes as well as from an increasing difference of primary origin effect between social classes in the realization of their educational choice.
Resumo:
Objective Interruptions are known to have a negative impact on activity performance. Understanding how an interruption contributes to human error is limited because there is not a standard method for analyzing and classifying interruptions. Qualitative data are typically analyzed by either a deductive or an inductive method. Both methods have limitations. In this paper a hybrid method was developed that integrates deductive and inductive methods for the categorization of activities and interruptions recorded during an ethnographic study of physicians and registered nurses in a Level One Trauma Center. Understanding the effects of interruptions is important for designing and evaluating informatics tools in particular and for improving healthcare quality and patient safety in general. Method The hybrid method was developed using a deductive a priori classification framework with the provision of adding new categories discovered inductively in the data. The inductive process utilized line-by-line coding and constant comparison as stated in Grounded Theory. Results The categories of activities and interruptions were organized into a three-tiered hierarchy of activity. Validity and reliability of the categories were tested by categorizing a medical error case external to the study. No new categories of interruptions were identified during analysis of the medical error case. Conclusions Findings from this study provide evidence that the hybrid model of categorization is more complete than either a deductive or an inductive method alone. The hybrid method developed in this study provides the methodical support for understanding, analyzing, and managing interruptions and workflow.