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Systematic control system design for process furnaces with multiple parallel tube-passes is addressed. The control objectives are to regulate furnace outlet temperature while holding the temperature rise across the individual tubes to be the same (tube-pass heat load balancing). With respect to furnace throughput (F tot), two operating scenarios are considered: (1) F tot is held constant, and (2) short-term transient variability in F tot is acceptable. Alternative control structures, CS1 for scenario 1 and CS2–CS3 for scenario 2, are synthesized and quantitatively evaluated for their closed-loop dynamic performance to expected load/servo changes. The scenario 1 heat load balancing problem is shown to exhibit strong multivariable dynamic interaction, and the control benefit of dynamic matrix control is quantified. On the basis of the results, the suitability of the alternative control systems in industrial settings is discussed.

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ObjectiveOur quest was to find an answer for “Why are some people able to recover 100% from a concussion/traumatic brain injury while others tend to have prolonged symptoms after their concussion/traumatic brain injury?”BackgroundThe prevalence of hyperhomocysteinemia in general is 5%–7% with increasing evidence showing higher prevalence of HHcy as age increases. The prevalence of vitamin D deficiency was 41.6% in the American population. The prevalence of vitamin B-12 deficiency is at least 40% in the patients of the Americas. With recent data, the prevalence of magnesium deficiency is around 10%–30% of the population. Hyperhomocysteinemia due MTHFR gene mutation B-12, B-6, magnesium, and folic acid deficiency is well established.Design/MethodsA retrospective study involving 45 patients was conducted in order to correlate the persistent symptoms concussion head injury/traumatic brain injury and their bio nutraceutical deficiency.ResultsThis data provides evidence that a patient's Homocysteine levels are significantly linearly related with their MoCA scores (t = −5.837, df = 34, p-value = 1.403e-06, [95% CI: −0.8406114 to −0.4936554]). In the mTBI group, for every 1 umol/L increase in Homocysteine levels, there is a 0.54217 decrease in MoCA scores. mTBI patients that had Homocysteine levels greater than 14 umol/L were 76% more likely to experience cognitive decline. The mean MoCA score of mTBI patients is significantly lower than the mean MoCA score of patients in the control group (t = −3.2898, df = 67, p-value = 0.0016, [95% CI: −6.710893 to −1.642642]). The mean Homocysteine levels of mTBI patients are significantly greater than the mean Homocysteine levels of patients in the control group (t = 2.2182, df = 85, p-value = 0.0292, [95% CI: 0.3039847 to 5.5603010]).ConclusionsmTBI patients should be routinely screened for serum homocysteine, vitamin D, B12, B6 and magnesium levels to know their risk for cognitive decline.