4,142 research outputs found
A parallel expert system for the control of a robotic air vehicle
Expert systems can be used to govern the intelligent control of vehicles, for example the Robotic Air Vehicle (RAV). Due to the nature of the RAV system the associated expert system needs to perform in a demanding real-time environment. The use of a parallel processing capability to support the associated expert system's computational requirement is critical in this application. Thus, algorithms for parallel real-time expert systems must be designed, analyzed, and synthesized. The design process incorporates a consideration of the rule-set/face-set size along with representation issues. These issues are looked at in reference to information movement and various inference mechanisms. Also examined is the process involved with transporting the RAV expert system functions from the TI Explorer, where they are implemented in the Automated Reasoning Tool (ART), to the iPSC Hypercube, where the system is synthesized using Concurrent Common LISP (CCLISP). The transformation process for the ART to CCLISP conversion is described. The performance characteristics of the parallel implementation of these expert systems on the iPSC Hypercube are compared to the TI Explorer implementation
Development of a comprehensive software engineering environment
The generation of a set of tools for software lifecycle is a recurring theme in the software engineering literature. The development of such tools and their integration into a software development environment is a difficult task because of the magnitude (number of variables) and the complexity (combinatorics) of the software lifecycle process. An initial development of a global approach was initiated in 1982 as the Software Development Workbench (SDW). Continuing efforts focus on tool development, tool integration, human interfacing, data dictionaries, and testing algorithms. Current efforts are emphasizing natural language interfaces, expert system software development associates and distributed environments with Ada as the target language. The current implementation of the SDW is on a VAX-11/780. Other software development tools are being networked through engineering workstations
The third dimension: How fire-related research can advance ecology and evolutionary biology
Most of the Earthâs vegetated surface is fireprone but the relevance of fire in understanding how nature works is not always recognized. We aim to show that, by adding the fire dimension to observations on biological phenomena, interpretations can be im-proved; how fire-related research can be used to answer âfundamentalâ questions in ecology; and how theories/models developed for fireprone ecosystems can be applied to advancing disturbance ecology, biogeography and evolutionary biology more generally. We compiled lists from the world-wide web of the most highly cited papers in fire ecology, and examined papers that had been approached from multiple viewpoints, including fire. We show that great advances over the last 20 years have been made in our understanding of the pivotal role of fire as a driver of many ecological processes and a powerful selective agent/evolutionary trigger among biota. We document 21 sets of observations originally interpreted in the context of the two traditional dimensions, prevailing environment and biotic interactions, but can also be shown to have a strong, if not dominant, historical link to fire. We note that fire-related research is able to address 55 of the 100 questions considered âfundamentalâ in ecology and that many have already received some attention in fireprone ecosystems. We show how theories/ models that had their origins in fireprone systems can be applied to other disturbance-prone systems and thus have wide application in ecology and evolutionary biology. Fire and other disturbances should be included as variables in research about possible critical environmental and biotic constraints controlling ecosystem function in general. Adding this third dimension to research endeavours greatly enriches our understanding of how nature works at the global scale in an era where ecosystems are changing rapidly and novel species-environmental interactions are emerging
Association of Interleukin-10 Cluster Genes and Salmonella Response in the Chicken
Salmonella enteritidis lipopolysaccharide stimulates interleukin 10 (IL10) gene expression in chickens. Four genes in the IL10 cluster [polymeric immunoglobulin receptor (PIGR), interleukin 10 (IL10), map kinase-activated protein kinase 2 (MAPKAPK2), and ligatin (LGTN)] plus dual-specificity tyrosine-(Y)-phosphorylation regulated kinase1A (DYRK1A) were investigated using the F8 generation of 2 related advanced intercross lines (AIL). The AIL were generated by crossing outbred broilers with dams of 2 highly inbred lines (Leghorn and Fayoumi). Intercrossing continued within the 2 dam lines. The F8 chicks (n = 132) were intraesophageally inoculated at 1 d with S. enteritidis. At d 7 or 8, both spleen tissue and cecal contents were cultured to quantify S. enteritidis load. The F8 population was genotyped for one single nucleotide polymorphism (SNP) per gene by using a multiplexed SNaPshot assay. Association of gene SNP with S. enteritidis bacterial burden was analyzed by the GLM. The MAPKAPK2 and IL10 genes were highly (P \u3c 0.001) associated with S. enteritidis burden in spleen tissue and cecal luminal content. Suggestive associations (P \u3c 0.05) of PIGR with spleen tissue and cecal content were found. The results suggest that SNP in MAPKAPK2 and IL10 were strongly associated with Salmonella burden and may be valuable in generating resistant birds by marker-assisted selection
Successful rehabilitation of species-rich heathlands after mining for heavy minerals
As human populations have been increasing, there has been a proportional increase in anthropogenic activities resulting in environmental degradation and destruction of the Earthâs biota (Novacek and Cleland 2001). For many people, biological diversity has intrinsic value, and as a result of increased community awareness and legislative obligations, the field of restoration ecology has emerged. This discipline is defined by SER (2004) as "the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed". The ultimate goal is to restore a self-supporting ecosystem that is resilient to environmental perturbations without the need for further assistance (Urbanska et al. 1997; SER 2004)
This report presents a study on shrubland restoration after heavy-mineral sand-mining near Eneabba, southwestern Australia. Four themes were highlighted in this report. First, restoration efforts were evaluated by comparing compositional, structural, and functional attributes between rehabilitated and surrounding natural analogues. Second, experimental fires were introduced to study sites to determine the vegetationâs resilience to natural disturbances. Third, growth and reproductive capacities of common species were compared between rehabilitated and natural sites. Fourth, recommendations are given to facilitate the restoration of natural analogues, and to improve the overall persistence of the restored shrublands after fire
Operation of LEP with bunch trains
Following an intensive MD program in 1994, a bunch train scheme was adopted as the operational mode for LEP. The configuration was used throughout 1995 and produced record luminosities. The year culminated in a high energy bunch train run which produced encouraging results for LEP2. In spite of this, the bunch train scheme met with varying degrees of success and the overall performance was not as good as expected. The performance of the machine is presented, together with the problems encountered and the various optimisation techniques used. The performance of related hardware and instrumentation is discussed
Vertical beam size, non-closure and LEP performance
The luminosity in LEP is critically dependent on the vertical beam size and thus on the effective control of contributing factors. Electrostatic separation bumps are used in LEP to avoid parasitic beam encounters and to allow the possibility of running with bunch trains. These vertical bumps are not closed at highest energies. The non-closure leads to different orbits for electrons and positrons and prevents effective minimisation of the residual vertical dispersion for both beams simultaneously. The various sources of the non-closure and a correction scheme which globally minimises the effects of this non-closure using only a few degrees of freedom are presented. The contributions to the vertical beam size from dispersion, coupling, beam-beam and other effects are quantified and the means used to control them are discussed
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