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101.
Minimizing risk using prediction uncertainty in neural networkestimation fusion and its application to papermaking 总被引:1,自引:0,他引:1
Edwards P.J. Peacock A.M. Renshaw D. Hannah J.M. Murray A.F. 《Neural Networks, IEEE Transactions on》2002,13(3):726-731
The paper presents Bayesian information fusion theory in the context of neural-network model combination. It shows how confidence measures can be combined with individual model estimates to minimize risk through the fusion process. The theory is illustrated through application to the real task of quality prediction in the papermaking industry. Prediction uncertainty estimates are calculated using approximate Bayesian learning. These are incorporated into model combination as confidence measures. Cost functions in the fusion center are used to control the influence of the confidence measures and improve the performance of the resultant committee. 相似文献
102.
Pfizer Inc. is a research based global pharmaceutical company committed to the discovery and development of innovative medicines that improve the quality of life of individuals throughout the world. In order to gain a competitive advantage over competitor companies in the discovery of new medicines, we must speed up drug discovery and drive down costs. Using non-combinatorial chemistry techniques increases the efficiency with which we discover new ‘leads,’ leveraging our drug discovery efforts through retaining complete control over the properties of each product made. Compound purification, managed through in-house software, augments the quality of data obtained upon biological screening of compounds. 相似文献
103.
104.
G Chow IG Roberts P Fallon M Onoe A Lloyd-Thomas MJ Elliott AD Edwards FJ Kirkham 《Canadian Metallurgical Quarterly》1997,11(4):633-639
BACKGROUND: The precise mechanisms involved in islet xenograft rejection remain unknown. The purpose of the present study was to determine cellular mechanisms responsible for islet xenograft rejection in the liver to facilitate finding a procedure for prevention of immune rejection. METHODS: Hepatic mononuclear cells (MNC) as well as splenocytes, peripheral blood MNC, and thymocytes from streptozotocin-induced diabetic mice (BALB/c) rejecting the intrahepatic rat (Lewis) islet xenografts were isolated and examined by two-color FACS analysis. RESULTS: The characteristic finding of the hepatic MNC from the mice rejecting islet xenografts compared with mice receiving isografts was a significant increase in the yield as well as in the percentage of the cells expressing CD3+ interleukin-2 receptor (IL-2R) alpha- beta+, CD3+ CD8alpha+ beta+, and T cell receptor (TCR) alphabeta+ lymphocyte function-associated antigen-1+. The expression of CD3 and TCR alphabeta of these T cells was found to be of intermediate intensity (TCR(int) cells). The expansion of these TCR(int) cells occurred predominantly in the liver. There was no significant difference in the cells expressing CD3+ IL-2R alpha+, CD3+ CD4+, CD3+ TCRgammadelta+, CD3- IL-2Rbeta+ (natural killer cells), and B220+ (B cells). In vivo administration of anti-IL-2Rbeta monoclonal antibody directed to the expanded cells produced a prevention of rejection. CONCLUSIONS: These findings suggest that islet xenograft rejection in the liver from rat to mouse is an event for which the TCR(int) cells are responsible. 相似文献
105.
Edwards G.S. Evertson D. Gabella W. Grant R. King T.L. Kozub J. Mendenhall M. Jin Shen Shores R. Storms S. Traeger R.H. 《IEEE journal of selected topics in quantum electronics》1996,2(4):810-817
The Vanderbilt free-electron laser (FEL) is a continuously tunable source of pulsed, mid-infrared radiation. FEL applications research has been underway for a decade. Recent experimental advances in FEL ablation of soft tissue indicate the potential for FEL-based protocols in surgery and medicine. In anticipation of these medical applications, the Vanderbilt FEL is being upgraded to meet the reliability and performance standards for a medical laser. Facilities for laser surgery have been constructed and equipped and medical delivery systems are being developed for pre-clinical and clinical research 相似文献
106.
107.
IG Edwards 《Canadian Metallurgical Quarterly》1998,114(6):16A-17A
108.
109.
Real-time multimedia communication applications demand performance requirements which differ significantly from conventional data communication applications. Current local area networks (LANs) provide efficient transport for bursty data traffic; however, they cannot necessarily provide quality of service guarantees for real-time communications. In this work we introduce and investigate an experimental priority protocol for supporting real-time communication on Ethernet, a popular implementation of multiple-access broadcast bus LANs. We examine the new protocol, known as Priority Mode-CSMA/CD (PM-CSMA/CD), providing a high priority (HP) class with CSMA/CD employed for standard priority (SP) traffic. PM-CSMA/CD performance is examined through computer simulation of videotelephony workstations operating over the shared bus LAN. Over all observed traffic conditions, the priority protocol provides performance satisfying real-time packet transport requirements of audio and video streams. The primary advantage of our protocol over similar priority schemes is its physical layer compatibility with standard CSMA/CD. The protocol also provides improved channel utilization with increasing high priority load, with no penalty in SP class performance at low to medium network loads. 相似文献
110.
RM Anderson PA Barr GJ Edwards MM Funnell JT Fitzgerald K Wisdom 《Canadian Metallurgical Quarterly》1996,22(1):28-33
BACKGROUND: Human serum represents an important barrier to the entry of most mucosal organisms into tissues and to the systemic circulation. If at all present, Helicobacter pylori within gastric tissue is rare, and bacteremia for this organism has been described only once. METHODS: To assess the susceptibility of H. pylori to the bactericidal activity present in normal human serum (NHS), we examined 13 H. pylori isolates. To assess the contributions of the classical and alternative complement pathways to killing, we added either C2-deficient or factor B-deficient serum, respectively, to heat-inactivated NHS. Also we assessed the ability of the strains to bind 125I-C3. RESULTS: After incubation for 60 minutes at 37 degrees C, all 13 H. pylori strains were killed by NHS; heating to 56 degrees C for 30 minutes ablated killing, indicating complement dependence for this phenomenon. In the absence of an antibody source, there was no killing when either an alternative or classical complement pathway source was used. Adding B-deficient serum to heat-inactivated normal human serum did not restore killing, but adding C2-deficient serum permitted partial killing. All of the 13 strains bound 125I-C3. Although the kinetics varied from strain to strain, C3 bound was significantly correlated (r = 0.61, p = 0.03) with serum susceptibility. CONCLUSIONS: H. pylori are susceptible to complement, alternative pathway activation appears critical, and C3 binding is a major locus of variability. 相似文献