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71.
Using redundancy is basic to fault-tolerant computing. N-modular redundancy (NMR) is in some ways analogous to the use of a repetition code where an information symbol is replicated as parity symbols in a codeword. Linear error-correcting codes (ECC) use linear combinations of information symbols as parity symbols to generate syndromes for error patterns. In this paper, ECC theory has been applied to derive redundant circuits that tolerate faults in both the modules and checkers. Circuits using comparators for diagnosis are derived with a non-graph-theoretic approach. Coding theoretic principles are applied directly to NMR, so that extensive diagnosis of the fault-tolerant system is achieved.  相似文献   
72.
Criteria to reduce sodium in restructured ham were developed by analyzing the effects of tumbling time (X1), tumbling speed (X2), and KCl substitution level (X3). Tumbled (68 kPa abs., 2 ° C) hams, stuffed into two 60 mm diameter water proof casings, were cooked in a water bath at 75°C to an internal temperature of 70±1°C. Quality was measured by evaluating color, shrinkage, textural parameters, water holding capacity (WHC), and sensory attributes. The conditions of XI = 15.6 h, X2 = 12 rpm, and X3 = 15.2% NaCl substitution with KCl minimized shrinkage and maximized cooked yield and WHC. Similarly, the conditions of X1 = 12.4 h, X2 = 16.8 rpm, and X3 = 18.3% substitution provided the optimal sensory attributes.  相似文献   
73.
A study was conducted to evaluate the mode of calcium-binding to four food protein sources. Following calcium-binding at pH levels of 7, 8, 9, 10 and 11, samples were evaluated for changes in the approximate molecular and subunit weight and in the isoelectric point of the soluble proteins. Data presented show that there were subunit interactions during the various pH incubations. This was especially true for the soy and wheat gluten proteins. Isoelectric points were found to decrease for soy, wheat, and leaf proteins after calcium binding.  相似文献   
74.
The interactive effects between ductile iron and PNL 76–68 borosilicate glass were investigated as a function of time in 90°C static deionized, tuff, and basalt groundwaters. A syn-ergistic effect occurs between the two materials, i. e. iron enhances glass dissolution and glass enhances iron corrosion. An iron silicate precipitate forms, part of which is colloidal in nature. This precipitate effectively removes many of the elements from solution and therefore inhibits the saturation effects which normally cause decreases in elemental removal rates. Thus, the effects of initial solution composition on the glass leach rates are significantly reduced and the relatively high early leach rates normally observed in deionized water are maintained for longer times due to the suppression of saturation effects. This results in more total elemental removal from the glass in all of the groundwaters evaluated. The precipitate and its colloidal form require further characterization.  相似文献   
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This paper presents the response of steel moment resisting frames with damage to their welded connections for two repair options: (1) reweld only; and (2) reweld and strengthen connection. Two different nonlinear dynamic analysis programs are used to research the effect of repairing and strengthening these weld failures and also for predicting the expected building response assuming that the connection is not repaired. The effect on response is studied for connections where weld failure reduces the capacity to 50, 20 and 5% of the original moment capacity. The frames selected for the research are in a real building damaged during the Northridge earthquake. They are subjected to an ensemble of artificial earthquake records that have an equal probability of occurring at the site for comparative studies. © 1997 John Wiley & Sons, Ltd.  相似文献   
79.
Pancreatic ductal adenocarcinoma (PDAC) is universally acknowledged as the cancer with the highest mortality rate. Berberine has high medicinal value and has been used as an anti-cancer agent. Hence the purpose of this study was to investigate the anti-cancer effect of berberine in PDAC. Berberine was shown to have a selective anti-cancer effect on PDAC by MTT assay in vitro. Pancreatic cancer stem cells (PCSCs), regulated by epithelial–mesenchymal transition (EMT), could promote the proliferation of PDAC cells. However, berberine suppressed the proliferation and stemness of PCSCs through immunofluorescence staining, stem cell sphere assays and so forth in vitro. In vivo, berberine reduced tumor size and decreased the expression levels of Ki67, a marker of cellular proliferation, in orthotopic pancreatic tumors. In addition, berberine inhibited the EMT signaling pathway by RT-PCR and Western blotting methods both in vitro and in vivo. Our study indicates that berberine inhibits the proliferation of PDAC cells both in vivo and in vitro. The mechanism of the anti-cancer effect of berberine likely involves the inhibition of EMT. Therefore, berberine may be a novel antineoplastic drug with clinical efficacy in PDAC.  相似文献   
80.
Although many articles have been published on the general priority scheduling problem, very few have been concerned with directly minimizing costs. The few studies which do consider overall costs do not use these costs in establishing a job's priority in the queue. This paper investigates how the time and cost performance of jobs are affected by the use of a rule which directly considers costs. A simulation model of a hypothetical job shop is used to examine several of these cost rules, as well as some common rules concerned with the timeliness of jobs. Performance measures include both time-oriented and cost-oriented measures. The results indicate that rules which directly consider costs (or profit) may prove practical for a manager where minimization of WTP and maximization of ROT are the primary and secondary objectives of the company  相似文献   
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