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In this paper an intelligent business forecaster for strategic business planning is presented. The forecaster is basically a multi‐layered fuzzy rule‐based neural network which integrates the basic elements and functions of a traditional fuzzy logic inference into a neural network structure. It has also been shown to be superior to two commercially available business forecasters in terms of learning speed and forecasting accuracy. This paper presents the architectural design of the intelligent business forecaster and the results of a study that has been carried out to compare its performance with that of the others. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
24.
Glia     
Chouard T  Gray N 《Nature》2010,468(7321):213
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25.
Currie TE  Greenhill SJ  Gray RD  Hasegawa T  Mace R 《Nature》2010,467(7317):801-804
There is disagreement about whether human political evolution has proceeded through a sequence of incremental increases in complexity, or whether larger, non-sequential increases have occurred. The extent to which societies have decreased in complexity is also unclear. These debates have continued largely in the absence of rigorous, quantitative tests. We evaluated six competing models of political evolution in Austronesian-speaking societies using phylogenetic methods. Here we show that in the best-fitting model political complexity rises and falls in a sequence of small steps. This is closely followed by another model in which increases are sequential but decreases can be either sequential or in bigger drops. The results indicate that large, non-sequential jumps in political complexity have not occurred during the evolutionary history of these societies. This suggests that, despite the numerous contingent pathways of human history, there are regularities in cultural evolution that can be detected using computational phylogenetic methods.  相似文献   
26.
We have deduced the entire 1,370-amino-acid sequence of the human insulin receptor precursor from a single complementary DNA clone. The precursor starts with a 27-amino-acid signal sequence, followed by the receptor alpha-subunit, a precursor processing enzyme cleavage site, then the beta-subunit containing a single 23-amino-acid transmembrane sequence. There are sequence homologies to human epidermal growth factor receptor and the members of the src family of oncogene products.  相似文献   
27.
Summary Neurons and glioblasts that arise in the ventricular zone migrate to form discrete nuclei and laminae as the central nervous system develops. By stably labeling precursor cells in the ventricular zone, pathways taken by different cells within an individual clone can be described. We have used recombinant retroviruses to label precursor cells with a heritable marker, theE. coli lacZ gene; clones of lacZ-positive cells are later mapped histochemically. Here we review results from three regions of the chicken central nervous system — the optic tectum, spinal cord, and forebrain - and compare them with previous results from mammalian cortex and other regions of the vertebrate CNS. In particular, we consider the relationship between migratory patterns and functional organization, the existence of multiple cellular sources of migratory guidance, and the issue of whether a cell's choice of migratory pathway influences its ultimate phenotype.  相似文献   
28.
G E Gray  S M Leber  J R Sanes 《Experientia》1990,46(9):929-940
Neurons and glioblasts that arise in the ventricular zone migrate to form discrete nuclei and laminae as the central nervous system develops. By stably labeling precursor cells in the ventricular zone, pathways taken by different cells within an individual clone can be described. We have used recombinant retroviruses to label precursor cells with a heritable marker, the E. coli lacZ gene; clones of lacZ-positive cells are later mapped histochemically. Here we review results from three regions of the chicken central nervous system--the optic tectum, spinal cord, and forebrain--and compare them with previous results from mammalian cortex and other regions of the vertebrate CNS. In particular, we consider the relationship between migratory patterns and functional organization, the existence of multiple cellular sources of migratory guidance, and the issue of whether a cell's choice of migratory pathway influences its ultimate phenotype.  相似文献   
29.
Identification of the skeletal remains of a murder victim by DNA analysis   总被引:7,自引:0,他引:7  
E Hagelberg  I C Gray  A J Jeffreys 《Nature》1991,352(6334):427-429
There is considerable anthropological and forensic interest in the possibility of DNA typing skeletal remains. Trace amounts of DNA can be recovered even from 5,500-year-old bones and multicopy human mitochondrial DNA sequences can frequently be amplified from such DNA using the polymerase chain reaction (PCR). But given the sensitivity of PCR, it is very difficult to exclude contaminating material. We now report the successful identification of the 8-year-old skeletal remains of a murder victim, by comparative typing of nuclear microsatellite markers in the remains and in the presumptive parents of the victim. This analysis establishes the authenticity of the bone DNA and the feasibility of bone DNA typing in forensic investigations.  相似文献   
30.
S D Gray 《Experientia》1976,32(3):350-351
Isometric tension was measured in arterial strips from neonatal lambs and adult sheep, after stimulation by angiotensin II. During the early maturation period immediately following birth (3 weeks) there was a progressive increase in sensitivity to the agent.  相似文献   
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