3,100 research outputs found
A software system for laboratory experiments in image processing
Laboratory experiments for image processing courses are usually software implementations of processing algorithms, but students of image processing come from diverse backgrounds with widely differing software experience. To avoid learning overhead, the software system should be easy to learn and use, even for those with no exposure to mathematical programming languages or object-oriented programming. The class library for image processing (CLIP) supports users with knowledge of C, by providing three C++ types with small public interfaces, including natural and efficient operator overloading. CLIP programs are compact and fast. Experience in using the system in undergraduate and graduate teaching indicates that it supports subject matter learning with little distraction from language/system learning
Ouerlike gesag en die gemolesteerde kind - die toereikendheid van die wet op kindersorg 74 van 1983
An analysis of the Child Care Act 74 of 1983 clearly illustrates that the Act is not directed at serving the best interest of the sexually abused child. Instead, it would seem that the priority placed on the interest of the community (by emphasizing the role of the criminal procedure) or the fitness of the parents to have custody of the child in child-care proceedings, is extremely detrimental to the interest of the child. The suggestion is put forward that it has become urgent for a family court to be established. In matters of this kind such a court can do valuable work to serve the best interest of the child by focussing on his personal situation, his having been the victim of the abuse
’n Beknopte regshistoriese oorsig van die vereistes vir die totstandkoming van ’n regsgeldige huwelik
A concise legal-historical overview of the requirements for establishing a legally valid marriage Within the Reformational tradition it is commonly accepted that marriage does not only have a typical and unique character, but that it also reflects the relationship between Christ and his church. This article focuses on the legal requirements for the solemnisation of a marriage in contemporary South African law against the legalhistorical background to the issue. In view of the fact that the formalities for solemnisation are aimed at legal certainty and the prevention of clandestine marriages, the conclusion is reached that the church may prescribe requirements for the establishment of a marriage within the parameters of its own dogma and for its own internal purposes. It is argued that the church should apply this perspective regarding members of a congregation who are involved in a long-standing relationship, but for reasons of their own, prefer not to enter into a legally recognised marriage
Baptism in ritual perspective: myth, symbol and metaphor as anthropological foundations for a baptismal theology
This thesis argues that Christian baptism is most profitably understood from the perspective of anthropological studies of ritual, A dialogue with its categories establishes that baptismal theology has often implicitly assumed social anthropology's findings on ritual in general. It also suggests that the primary ritual categories of myth, symbol and metaphor are foundational to baptism's theological development. The anthropology of myth is deployed to locate the narrative basis for baptism. The proposal is made that the story of Jesus' Baptism, which is understood as the revelation of the eschatological new creation, provides baptismal ritual with its imitative source and legitimates its symbols and metaphors. An analysis of iconography is an important part of this justification. This proposal is developed by exploring the properties of baptismal symbols. The concepts of symbolic elusiveness, deep structure and natural symbolism are exploited to give an account of symbols based on water and oil. The sensual experience of olfaction and the flow of human blood are found to be important interpretative concepts which lead naturally to a consideration of the corporeality of baptismal symbolism. Recognising that symbols promote a shared ritual experience, the properties of ritual metaphors are then considered as the primary means for facilitating a baptismal identity. Criteria for an evaluation of the three major metaphors - birth, death and washing - are derived from anthropology and applied. It is concluded that the metaphor of childbirth has a strong claim to be regarded as the appropriate primary metaphor for organising baptism's ritual context. Baptism thus understood offers fresh contours for baptismal theology today and overcomes some of the difficulties presented by more traditional methodologies. Especially, it allows contemporary concerns about baptism to be effectively addressed. Among these are questions about the intelligibility of its liturgical symbols and the relationships between its key metaphors
Treatment of input uncertainty in hydrologic modeling: Doing hydrology backward with Markov chain Monte Carlo simulation
There is increasing consensus in the hydrologic literature that an appropriate framework for streamflow forecasting and simulation should include explicit recognition of forcing and parameter and model structural error. This paper presents a novel Markov chain Monte Carlo (MCMC) sampler, entitled differential evolution adaptive Metropolis (DREAM), that is especially designed to efficiently estimate the posterior probability density function of hydrologic model parameters in complex, high-dimensional sampling problems. This MCMC scheme adaptively updates the scale and orientation of the proposal distribution during sampling and maintains detailed balance and ergodicity. It is then demonstrated how DREAM can be used to analyze forcing data error during watershed model calibration using a five-parameter rainfall-runoff model with streamflow data from two different catchments. Explicit treatment of precipitation error during hydrologic model calibration not only results in prediction uncertainty bounds that are more appropriate but also significantly alters the posterior distribution of the watershed model parameters. This has significant implications for regionalization studies. The approach also provides important new ways to estimate areal average watershed precipitation, information that is of utmost importance for testing hydrologic theory, diagnosing structural errors in models, and appropriately benchmarking rainfall measurement devices
Equifinality of formal (DREAM) and informal (GLUE) Bayesian approaches in hydrologic modeling?
In recent years, a strong debate has emerged in the hydrologic literature regarding what constitutes an appropriate framework for uncertainty estimation. Particularly, there is strong disagreement whether an uncertainty framework should have its roots within a proper statistical (Bayesian) context, or whether such a framework should be based on a different philosophy and implement informal measures and weaker inference to summarize parameter and predictive distributions. In this paper, we compare a formal Bayesian approach using Markov Chain Monte Carlo (MCMC) with generalized likelihood uncertainty estimation (GLUE) for assessing uncertainty in conceptual watershed modeling. Our formal Bayesian approach is implemented using the recently developed differential evolution adaptive metropolis (DREAM) MCMC scheme with a likelihood function that explicitly considers model structural, input and parameter uncertainty. Our results demonstrate that DREAM and GLUE can generate very similar estimates of total streamflow uncertainty. This suggests that formal and informal Bayesian approaches have more common ground than the hydrologic literature and ongoing debate might suggest. The main advantage of formal approaches is, however, that they attempt to disentangle the effect of forcing, parameter and model structural error on total predictive uncertainty. This is key to improving hydrologic theory and to better understand and predict the flow of water through catchment
Pullback permanence in a non-autonomous competitive Lotka–Volterra model
AbstractThe goal of this work is to study in some detail the asymptotic behaviour of a non-autonomous Lotka–Volterra model, both in the conventional sense (as t→∞) and in the “pullback” sense (starting a fixed initial condition further and further back in time). The non-autonomous terms in our model are chosen such that one species will eventually die out, ruling out any conventional type of permanence. In contrast, we introduce the notion of “pullback permanence” and show that this property is enjoyed by our model. This is not just a mathematical artifice, but rather shows that if we come across an ecology that has been evolving for a very long time we still expect that both species are represented (and their numbers are bounded below), even if the final fate of one of them is less happy. The main tools in the paper are the theory of attractors for non-autonomous differential equations, the sub-supersolution method and the spectral theory for linear elliptic equations
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Results of a seepage investigation at Bear Creek Valley, Oak Ridge, Tennessee, January through September 1994
A seepage investigation was conducted of 4,600 acres of Bear Creek Valley southwest of the Y-12 Plant, Oak Ridge, Tennessee, for the period of January through September 1994. The data was collected to help the Y-12 Environmental Restoration Program develop a better understanding of ground-water and surface-water interactions, recharge and discharge relations, and ground-water flow patterns. The project was divided into three phases: a reconnaissance and mapping of seeps, springs, and stream-measurement sites; a high base flow seepage investigation; and a low base flow seepage investigation. This report describes the results of the investigation. It includes a map showing measurement site locations and tables that list the coordinates for each site and measurements of discharge, pH, specific conductance, temperature, and dissolved oxygen
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