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91.
The paper presents a case study of the development of an expert decision support system which uses simple heuristic methods for fast determination of routes for simultaneous signals in a transmission network of limited capacity. It illustrates how heuristic solutions can be embodied in a model-based DSS and how the standard decision support literature, although intuitively appealing, provides little practical assistance in system construction or classification 相似文献
92.
Steven Blaine 《Materials and Structures》1997,30(6):362-365
High energy mixing of calcium sulfate hemihydrate/water slurries provides a means to accelerate the hydration leading to gypsum formation. Additional benefits associated with high energy mixing include enhanced strength of the resulting gypsum casts. In order to exploit the advantages of high energy mixing, an understanding of the relationship between mixing energy and set acceleration is needed. The present study investigated the relationship between a chemical accelerator and high energy mixing for the purpose of set acceleration. A mathematical model of this relationship allows calculation of the time to achieve 50% hydration given the added specific mixing energy, the percentage of added chemical accelerator by weight of stucco, and the water to stucco ratio for a given slurry. Use of this model along with experimental data allowed a comparison of the accelerative efficacy of mixing energy relative to chemical accelerator. The results show that the accelerative capacity of high energy mixing is rather modest compared to that of the chemical accelerator, with a ten-fold increase in mixing energy required to maintain the same time to achieve 50% hydration when the chemical accelerator loading is reduced by 0.03%. 相似文献
93.
SR Hall 《Canadian Metallurgical Quarterly》1996,21(3):225-229
An asymmetric triazine derivative, HOE 092 V,2-[3,5-alpha-dichloro-4-(4-methyl-sulfonylphenoxy)-phenyl]- 1-methyl-hexahydro-1,2,4-triazine-3,5-dion, was tested in vivo against Glugea anomala parasitizing the connective tissue of sticklebacks (Gasterosteus aculeatus). Naturally infected sticklebacks were incubated in 10-1 plastic aquaria in water containing 0, 2.5, 5, and 10 micrograms HOE 092 V/ml for 2, 3, and 4 h at 22 degrees C. As seen at the ultrastructural level, the drug caused severe damage to all developmental stages of G. anomala except the mature spores. Starting with a dose of 2.5 micrograms/ml, the drug caused significant damage on uni- and multinucleate meronts, sporogonial plasmodia, and sporoblasts. The damage mainly consisted in a decrease in the number of ribosomes, an enlargement of the smooth endoplasmic reticulum and a vacuolization of the cytoplasma. When treatment was done with 5 micrograms for 2 h, multinucleate meronts and sporogonial plasmodia were no longer detectable, and the sporoblasts and the prespore stages except the mature spores had shrunk. After incubation of the infected fish with 10 micrograms HOE 092 V/ml and 4 h exposure, uninucleate meronts were no longer detectable by means of transmission electron microscopy. In the sporoblast mother cells, vacuolization of the cytoplasma and lysis of the nuclei occurred. However, mature spores were not affected. It seems likely that HOE 092 V can be successfully applied in medicinal baths against Microsporidia in fish. The infected fish should be incubated in separate, aerated containers. 相似文献
94.
95.
LA Parada G Bardi M Hallén I H?gerstrand KG Tranberg F Mitelman B Johansson 《Canadian Metallurgical Quarterly》1997,21(11):1381-1386
Hepatoblastomas usually occur in children < 3 years of age, and only occasional adult cases have been described. To date, 20 cytogenetically abnormal childhood hepatoblastomas have been reported. Karyotypic investigations have shown that most hepatoblastomas are diploid or hyperdiploid, often displaying trisomies for chromosomes 2 and 20. We have cytogenetically investigated an adult hepatoblastoma for which no previous karyotypic data exist. A hypertriploid stemline with multiple numerical and structural chromosomal aberrations, including +2 and +20, was found. In addition, the tumor displayed extensive clonal evolution with 11 subclones. Although the tumor thus displayed some chromosomal abnormalities commonly observed in childhood tumors, providing further support for the importance of these abnormalities in the development of hepatoblastoma, the level of genomic complexity seen in the present case has never been described in childhood hepatoblastomas and may suggest a different etiology or pathogenesis. 相似文献
96.
Steven Spier 《The Journal of Architecture》1998,3(2):135-146
William Forsythe's research into ways of engendering and organising movement has led him to pursue counterpoint, proprioperception, entrainment, and authenticity for organisational principles that also allow improvisation. Artistic director and choreographer of the Ballett Frankfurt, and himself trained in ballet, Forsythe shows an appreciation of and often a critical engagement with classical dance, transforming and revitalising it. When he works collaboratively, Forsythe challenges the traditional distinction between choreographer and dancer, thus questioning hierarchy, authorship, and disciplinary boundaries. 相似文献
97.
98.
C. A. Hall L. E. De Carlo M. L. Wenner N. L. Troyani 《International journal for numerical methods in engineering》1993,36(21):3617-3627
The computational method for large deformation plasticity called differential equations on a manifold (DEM) has previously been shown to be effective for axisymmetric and plane strain sheet metal forming problems. The method has now been formulated for in-plane stretching problems, incorporated into a computer code, and applied to several problems. The code's performance is robust and accurate, as evidenced by a comparison with other published results. Incorporation of an automatic mesh generator significantly reduces data preparation time. 相似文献
99.
Little is known of the current smoking cessation activities of practice nurses and their attitudes toward giving smoking cessation advice. This study aimed to (a) compare practice nurses' reports of giving smoking cessation advice as part of cervical screening with their reports of giving such advice in cardiovascular disease screening and diabetes care, (b) compare their beliefs about providing such advice in these three contexts, and (c) determine the strongest predictors of their reports of giving smoking cessation advice. A survey was completed by 152 practice nurses in the United Kingdom. The frequency with which they reported giving smoking cessation advice and their beliefs about giving such advice in three contexts are reported. Nurses reported being more likely to give smoking cessation advice and had more positive beliefs about giving it in the more traditional contexts of cardiovascular screening and diabetes care compared with cervical screening. Beliefs about the appropriateness and practicality of giving such advice in the latter context were the strongest predictors of nurses' reports of doing so. This study provides guidance on the potential barriers that need to be overcome to increase the frequency with which nurses give smoking cessation advice in the context of cervical screening. 相似文献
100.
Attention deficit and conduct disorders require an important yet often difficult differential diagnosis. Prior efforts to determine which symptoms are optimal for making this differential diagnosis have been limited by a reliance on statistics that do not supply the probability of the disorders given a symptom's presence (positive predictive power) or the probability that the disorder is not present given the absence of the symptom (negative predictive power). This investigation examined the utility of these latter statistics in the differential diagnosis of childhood attention deficit and conduct disorders. The data consisted of symptoms from a standardized maternal psychiatric interview collected for a sample of 76 clinic-referred boys. Results indicated that some symptoms are optimal as inclusion criteria, some as exclusion criteria, some as neither, and some as both. Furthermore, some symptoms that have been traditionally associated with the diagnosis of one disorder were actually found to be more useful in the diagnosis of the other disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献