891 resultados para Problem of evil
Resumo:
In visual object detection and recognition, classifiers have two interesting characteristics: accuracy and speed. Accuracy depends on the complexity of the image features and classifier decision surfaces. Speed depends on the hardware and the computational effort required to use the features and decision surfaces. When attempts to increase accuracy lead to increases in complexity and effort, it is necessary to ask how much are we willing to pay for increased accuracy. For example, if increased computational effort implies quickly diminishing returns in accuracy, then those designing inexpensive surveillance applications cannot aim for maximum accuracy at any cost. It becomes necessary to find trade-offs between accuracy and effort. We study efficient classification of images depicting real-world objects and scenes. Classification is efficient when a classifier can be controlled so that the desired trade-off between accuracy and effort (speed) is achieved and unnecessary computations are avoided on a per input basis. A framework is proposed for understanding and modeling efficient classification of images. Classification is modeled as a tree-like process. In designing the framework, it is important to recognize what is essential and to avoid structures that are narrow in applicability. Earlier frameworks are lacking in this regard. The overall contribution is two-fold. First, the framework is presented, subjected to experiments, and shown to be satisfactory. Second, certain unconventional approaches are experimented with. This allows the separation of the essential from the conventional. To determine if the framework is satisfactory, three categories of questions are identified: trade-off optimization, classifier tree organization, and rules for delegation and confidence modeling. Questions and problems related to each category are addressed and empirical results are presented. For example, related to trade-off optimization, we address the problem of computational bottlenecks that limit the range of trade-offs. We also ask if accuracy versus effort trade-offs can be controlled after training. For another example, regarding classifier tree organization, we first consider the task of organizing a tree in a problem-specific manner. We then ask if problem-specific organization is necessary.
Resumo:
Using Hilbert theory and Mindlin's couple stress theory, the problem of two-dimensional circular inhomogeneity (when the inserted material is of different size than the size of the cavity and having different elastic constants) is studiedin this paper. Stress could be bounded at infinity. The formulation is valid also for regions other then the circular ones when the matrix is finite has also been tackled. Numerical results are in conformity with the fact that the effect of couple stresses is negligible when the ratio of the smallest dimension of the body to the cahracteristic length is large.
Resumo:
The problem of ‘wet litter’, which occurs primarily in grow-out sheds for meat chickens (broilers), has been recognised for nearly a century. Nevertheless, it is an increasingly important problem in contemporary chicken-meat production as wet litter and associated conditions, especially footpad dermatitis, have developed into tangible welfare issues. This is only compounded by the market demand for chicken paws and compromised bird performance. This review considers the multidimensional causal factors of wet litter. While many causal factors can be listed it is evident that the critical ones could be described as micro-environmental factors and chief amongst them is proper management of drinking systems and adequate shed ventilation. Thus, this review focuses on these environmental factors and pays less attention to issues stemming from health and nutrition. Clearly, there are times when related avian health issues of coccidiosis and necrotic enteritis cannot be overlooked and the development of efficacious vaccines for the latter disease would be advantageous. Presently, the inclusion of phytate-degrading enzymes in meat chicken diets is routine and, therefore, the implication that exogenous phytases may contribute to wet litter is given consideration. Opinion is somewhat divided as how best to counter the problem of wet litter as some see education and extension as being more beneficial than furthering research efforts. However, it may prove instructive to assess the practice of whole grain feeding in relation to litter quality and the incidence of footpad dermatitis. Additional research could investigate the relationships between dietary concentrations of key minerals and the application of exogenous enzymes with litter quality.
The Mediated Immediacy : João Batista Libanio and the Question of Latin American Liberation Theology
Resumo:
This study is a systematic analysis of mediated immediacy in the production of the Brazilian professor of theology João Batista Libanio. He stresses both ethical mediation and the immediate character of the faith. Libanio has sought an answer to the problem of science and faith. He makes use of the neo-scholastic distinction between matter and form. According to St. Thomas Aquinas, God cannot be known as a scientific object, but it is possible to predicate a formal theological content of other subject matter with the help of revelation. This viewpoint was emphasized in neo-Thomism and supported by the liberation theologians. For them, the material starting point was social science. It becomes a theologizable or revealable (revelabile) reality. This social science has its roots in Latin American Marxism which was influenced by the school of Louis Althusser and considered Marxism a science of history . The synthesis of Thomism and Marxism is a challenge Libanio faced, especially in his Teologia da libertação from 1987. He emphasized the need for a genuinely spiritual and ethical discernment, and was particularly critical of the ethical implications of class struggle. Libanio s thinking has a strong hermeneutic flavor. It is more important to understand than to explain. He does not deny the need for social scientific data, but that they cannot be the exclusive starting point of theology. There are different readings of the world, both scientific and theological. A holistic understanding of the nature of religious experience is needed. Libanio follows the interpretation given by H. C. de Lima Vaz, according to whom the Hegelian dialectic is a rational circulation between the totality and its parts. He also recalls Oscar Cullmann s idea of God s Kingdom that is already and not yet . In other words, there is a continuous mediation of grace into the natural world. This dialectic is reflected in ethics. Faith must be verified in good works. Libanio uses the Thomist fides caritate formata principle and the modern orthopraxis thinking represented by Edward Schillebeeckx. One needs both the ortho of good faith and the praxis of the right action. The mediation of praxis is the mediation of human and divine love. Libanio s theology has strong roots in the Jesuit spirituality that places the emphasis on contemplation in action.
Resumo:
This study examines philosophically the main theories and methodological assumptions of the field known as the cognitive science of religion (CSR). The study makes a philosophically informed reconstruction of the methodological principles of the CSR, indicates problems with them, and examines possible solutions to these problems. The study focuses on several different CSR writers, namely, Scott Atran, Justin Barrett, Pascal Boyer and Dan Sperber. CSR theorising is done in the intersection between cognitive sciences, anthropology and evolutionary psychology. This multidisciplinary nature makes CSR a fertile ground for philosophical considerations coming from philosophy of psychology, philosophy of mind and philosophy of science. The study begins by spelling out the methodological assumptions and auxiliary theories of CSR writers by situating these theories and assumptions in the nexus of existing approaches to religion. The distinctive feature of CSR is its emphasis on information processing: CSR writers claim that contemporary cognitive sciences can inform anthropological theorising about the human mind and offer tools for producing causal explanations. Further, they claim to explain the prevalence and persistence of religion by cognitive systems that undergird religious thinking. I also examine the core theoretical contributions of the field focusing mainly on the (1) “minimally counter-intuitiveness hypothesis” and (2) the different ways in which supernatural agent representations activate our cognitive systems. Generally speaking, CSR writers argue for the naturalness of religion: religious ideas and practices are widespread and pervasive because human cognition operates in such a way that religious ideas are easy to acquire and transmit. The study raises two philosophical problems, namely, the “problem of scope” and the “problem of religious relevance”. The problem of scope is created by the insistence of several critics of the CSR that CSR explanations are mostly irrelevant for explaining religion. Most CSR writers themselves hold that cognitive explanations can answer most of our questions about religion. I argue that the problem of scope is created by differences in explanation-begging questions: the former group is interested in explaining different things than the latter group. I propose that we should not stick too rigidly to one set of methodological assumptions, but rather acknowledge that different assumptions might help us to answer different questions about religion. Instead of adhering to some robust metaphysics as some strongly naturalistic writers argue, we should adopt a pragmatic and explanatory pluralist approach which would allow different kinds of methodological presuppositions in the study of religion provided that they attempt to answer different kinds of why-questions, since religion appears to be a multi-faceted phenomenon that spans over a variety of fields of special sciences. The problem of religious relevance is created by the insistence of some writers that CSR theories show religious beliefs to be false or irrational, whereas others invoke CSR theories to defend certain religious ideas. The problem is interesting because it reveals the more general philosophical assumptions of those who make such interpretations. CSR theories can (and have been) interpreted in terms of three different philosophical frameworks: strict naturalism, broad naturalism and theism. I argue that CSR theories can be interpreted inside all three frameworks without doing violence to the theories and that these frameworks give different kinds of results regarding the religious relevance of CSR theories.
Resumo:
Vibration problem of generally orthotropic plates with particular attention to plates of skew geometry is studied. The formulation is based on orthotropic plate theory with arbitrary orientation of the principal axes of orthotropy. The boundary conditions considered are combinations of simply supported, clamped, and free-edge conditions. Approximate solution for frequencies and modes is obtained by the Ritz method using products of appropriate beam characteristic functions as admissible functions. The variation of frequencies and modes with orientation of the axes of orthotropy is examined for different skew angles and boundary conditions. Features such as "crossings" and "quasi-degeneracies" of the frequency curves are found to occur with variation of the orientation of the axes of orthotropy for a given geometry of the skew plate. It is also found that for each combination of skew angle and side ratio, a particular orientation of the axes gives the highest value for the fundamental frequency of the plate.
Resumo:
Creeping flow hydrodynamics combined with diffusion boundary layer equation are solved in conjunction with free-surface cell model to obtain a solution of the problem of convective transfer with surface reaction for flow parallel to an array of cylindrical pellets at high Peclet numbers and under fast and intermediate kinetics regimes. Expressions are derived for surface concentration, boundary layer thickness, mass flux and Sherwood number in terms of Damkoehler number, Peclet number and void fraction of the array. The theoretical results are evaluated numerically.
Resumo:
The purpose of this study is to evaluate contemporary philosophical models for global ethics in light of the Catholic theologian Hans Küng s Global Ethic Project (Projekt Weltethos). Küng s project starts with the motto, No survival without world ethos. No global peace without peace between religions. I will use the philosophically multidimensional potential of Projekt Weltethos in terms of its possible philosophical interpretations to evaluate the general discussion of global ethics within political philosophy today. This is important in its own right, but also because through it, opportunities will emerge to articulate Küng s relatively general argument in a way that leaves less room for mutually contradictory concretizations of what global ethics ultimately should be like. The most important question in this study is the problem of religious and ideological exclusivism and its relation to the ethically consistent articulation of global ethics. I will first explore the question of the role of religion as the basis for ethics in general and what Küng may mean by his claim that only the unconditional can oblige unconditionally. I will reconstruct two different overall philosophical interpretations of the relationship between religious faith and human rationality, each having two different sub-divisions: a liberal interpretation amounts to either a Kantian-Scheiermacherian or a Jaspersian view, whereas what I call postliberal interpretation amounts to either an Aristotelian-Thomistic or an Augustinian view. Thereafter, I will further clarify how Küng views the nature of ethics beyond the question of its principal foundation in religious faith: Küng searches for a middle way between consequentialist and non-consequentialist ethics, a way in which the latter dimension has the final stake. I will then set out to concretize further this more or less general notion of the theoretical potential of Projekt Weltethos in terms of certain precise philosophico-political models. I categorize these models according to their liberal or postliberal orientation. The liberal concretization leads me to consider a wide spectrum of post-Kantian and post-Hegelian models from Rawls to Derrida, while the alternative concretization opens up my ultimate argument in favor of a postliberal type of modus vivendi. I will suggest that the only theoretically and practically plausible way to promote global ethics, in itself a major imperative today, is the recognition of a fundamental and necessary contest between mutually exclusive ideologies in the public sphere. On this basis I will proceed to my postliberal proposal, namely, that a constructive and peaceful encountering of exclusive difference as an ethical vantage point for an intercultural and inter-religious peace dialogue is the most acute challenge for global ethics today.
Resumo:
Regional autonomy in Indonesia was initially introduced as a means of pacifying regional disappointment at the central government. Not only did the Regional Autonomy Law of 1999 give the Balinese a chance to express grievance regarding the centralist policies of the Jakarta government but also provided an opportunity to return to the regional, exclusive, traditional village governance (desa adat). As a result, the problems faced by the island, particularly ethnic conflicts, are increasingly handled by the mechanism of this traditional type of governance. Traditional village governance with regard to ethnic conflicts (occurring) between Balinese and migrants has never been systematically analyzed. Existing analyses emphasized only the social context, but do not explain either the cause of conflicts and the ensuing problems entails or the virtues of traditional village governance mechanisms for mediating in the conflict. While some accounts provide snapshots, they lack both theoretical and conflict study perspective. The primary aim of this dissertation is to explore the expression and the causes of conflict between the Balinese and migrants and to advance the potential of traditional village governance as a means of conflict resolution with particular reference to the municipality of Denpasar. One conclusion of the study is that the conflict between the Balinese and migrants has been expressed on the level of situation/contradiction, attitudes, and behavior. Yet the driving forces behind the conflict itself consist of the following factors: absence of cooperation; incompatible position and perception; inability to communicate effectively; and problem of inequality and injustice, which comes to the surface as a social, cultural, and economic problem. This complex of factors fuels collective fear for the future of both groups. The study concludes that traditional village governance mechanisms as a means of conflict resolution have not yet been able to provide an enduring resolution for the conflict. Analysis shows that the practice of traditional village governance is unable to provide satisfactory mechanisms for the conflict as prescribed by conflict resolution theory. Traditional village governance, which is derived from the exclusive Hindu-Balinese culture, is accepted as more legitimate among the Balinese than the official governance policies. However, it is not generally accepted by most of the Muslim migrants. In addition, traditional village governance lacks access to economic instruments, which weakens its capacity to tackle the economic roots of the conflict. Thus the traditional mechanisms of migrant ordinance , as practiced by the traditional village governance have not yet been successful in penetrating all aspects of the conflict. Finally, one of the main challenges for traditional village governance s legal development is the creation of a regional legal system capable of accommodating rapid changes in line with the national and international legal practices. The framing of the new laws should be responsive to the aspirations of a changing society. It should not only protect the various Balinese communities interests, but also that of other ethnic groups, especially those of the minority. In other words, the main challenge to traditional village governance is its ability to develop flexibility and inclusiveness.
Resumo:
When a uniform flow of any nature is interrupted, the readjustment of the flow results in concentrations and rare-factions, so that the peak value of the flow parameter will be higher than that which an elementary computation would suggest. When stress flow in a structure is interrupted, there are stress concentrations. These are generally localized and often large, in relation to the values indicated by simple equilibrium calculations. With the advent of the industrial revolution, dynamic and repeated loading of materials had become commonplace in engine parts and fast moving vehicles of locomotion. This led to serious fatigue failures arising from stress concentrations. Also, many metal forming processes, fabrication techniques and weak-link type safety systems benefit substantially from the intelligent use or avoidance, as appropriate, of stress concentrations. As a result, in the last 80 years, the study and and evaluation of stress concentrations has been a primary objective in the study of solid mechanics. Exact mathematical analysis of stress concentrations in finite bodies presents considerable difficulty for all but a few problems of infinite fields, concentric annuli and the like, treated under the presumption of small deformation, linear elasticity. A whole series of techniques have been developed to deal with different classes of shapes and domains, causes and sources of concentration, material behaviour, phenomenological formulation, etc. These include real and complex functions, conformal mapping, transform techniques, integral equations, finite differences and relaxation, and, more recently, the finite element methods. With the advent of large high speed computers, development of finite element concepts and a good understanding of functional analysis, it is now, in principle, possible to obtain with economy satisfactory solutions to a whole range of concentration problems by intelligently combining theory and computer application. An example is the hybridization of continuum concepts with computer based finite element formulations. This new situation also makes possible a more direct approach to the problem of design which is the primary purpose of most engineering analyses. The trend would appear to be clear: the computer will shape the theory, analysis and design.
Resumo:
In many instances we find it advantageous to display a quantum optical density matrix as a generalized statistical ensemble of coherent wave fields. The weight functions involved in these constructions turn out to belong to a family of distributions, not always smooth functions. In this paper we investigate this question anew and show how it is related to the problem of expanding an arbitrary state in terms of an overcomplete subfamily of the overcomplete set of coherent states. This provides a relatively transparent derivation of the optical equivalence theorem. An interesting by-product is the discovery of a new class of discrete diagonal representations.
Resumo:
The problem of optimum design of a Lanchester damper for minimum force transmission from a viscously damped single degree of freedom system subjected to harmonic excitation is investigated. Explicit expressions are developed for determining the optimum absorber parameters. It is shown that for the particular case of the undamped single degree of freedom system the results reduce to the classical ones obtained by using the concept of a fixed point on the transmissibility curves.
Resumo:
Since the declaration by the United Nations that awareness raising should be a key part of efforts to combat human trafficking, government and non-government organisations have produced numerous public awareness campaigns designed to capture the public’s attention and sympathy. These campaigns represent the ‘problem’ of trafficking in specific ways, creating heroes and villains by placing the blame for trafficking on some, while obscuring the responsibility of others. This paper adopts Carol Bacchi’s ‘What is the problem represented to be?’ framework for examining the politicisation of problem representation in 18 anti-trafficking awareness campaigns. It is argued that these campaigns construct a narrow understanding of the problem through the depiction of ‘ideal offenders’. In particular, a strong focus on the demand for commercial sex as causative of human trafficking serves to obscure the problematic role of consumerism in a wide range of industries, and perpetuates an understanding of trafficking that fails to draw a necessary distinction between the demand for labour, and the demand for ‘exploitable’ labour. This problem representation also obscures the role governments in destination countries may play in causing trafficking through imposing restrictive migration regimes that render migrants vulnerable to traffickers.
Resumo:
The problem of decoupling a class of non-linear two degrees of freedom systems is studied. The coupled non-linear differential equations of motion of the system are shown to be equivalent to a pair of uncoupled equations. This equivalence is established through transformation techniques involving the transformation of both the dependent and independent variables. The sufficient conditions on the form of the non-linearity, for the case wherein the transformed equations are linear, are presented. Several particular cases of interest are also illustrated.
Resumo:
Any stressed photoelastic medium can be reduced to an optically equivalent model consisting of a linear retarder, with retardation delta1 and principal axis at azimuth phgr1, and a pure rotator of power phgr2. The paper describes two simple methods to determine these quantities experimentally. Further, a method is described to overcome the problem of rotational effects in scattered-light investigations. This new method makes use of the experimentally determined characteristic parameters.