Integrating process and controller models for the design of self-optimizing control

The steady-state behavior of an existing plant depends on the independent input variables, process equipment and process controllers. This paper presents a method for formulating models that represent the effects of controllers when they are included within a steady-state process flowsheet. The method replaces the controller equations with the equivalent stationarity conditions representing the relationship between the controlled variables and the implemented manipulated variables at steady state. The method is demonstrated for the centralized multivariable Dynamic Matrix Control algorithm applied to two processes, binary distillation and gasoline blending. The integrated process and control system simulation is used to design controllers that improve the profitability of processes without extensive real-time calculations; this is sometimes termed self-optimizing control. For both processes, controllers were designed that yielded higher profit than standard control methods and that approached the highest possible profit achieved by frequent real-time optimization.     

Electromagnetic interference of cardiac rhythmic monitoring devices to radio frequency identification: analytical analysis and mitigation methodology

Increasing density of wireless communication and development of radio frequency identification (RFID) technology in particular have increased the susceptibility of patients equipped with cardiac rhythmic monitoring devices (CRMD) to environmental electro magnetic interference (EMI). Several organizations reported observing CRMD EMI from different sources. This paper focuses on mathematically analyzing the energy as perceived by the implanted device, i.e., voltage. Radio frequency (RF) energy transmitted by RFID interrogators is considered as an example. A simplified front-end equivalent circuit of a CRMD sensing circuitry is proposed for the analysis following extensive black-box testing of several commercial pacemakers and implantable defibrillators. After careful understanding of the mechanics of the CRMD signal processing in identifying the QRS complex of the heart-beat, a mitigation technique is proposed. The mitigation methodology introduced in this paper is logical in approach, simple to implement and is therefore applicable to all wireless communication protocols.     

Physiological responses in nonheat acclimated horses performing treadmill exercise in cool (20 degrees C/40% RH), hot dry (30 degrees C/40% RH) and hot humid (30 degrees C/80% RH) conditions

The aim of the present study was to determine the effect of different environmental conditions on physiological response to exercise. Four winter acclimatised, nonheat acclimated horses of different breeds were exercised at 20 degrees C/40% RH (CD), 30 degrees C/40% RH (HD) and 30 degrees C/80% RH (HH). The exercise test was designed to represent the structure and intensity of a One star Speed and Endurance test (competition exercise test [CET]). All 4 horses were able to complete the full CET (60 min + 30 min active recovery) in CD and HD, but only one horse completed the CET in HH. Two horses were stopped because of pronounced general fatigue and one because of a right atrial temperature (TRA) of 43 degrees C. Oxygen uptake on each phase was not different between CD and HD, but was higher during Phases B, C and D in HH. Mean peak TRA at the end of Phase D was 40.3 +/- 0.2, 41.6 +/- 0.4 and 42 +/- 0.3 degrees C for CD, HD and HH, respectively. Corresponding, mean peak rectal temperatures (TREC) following Phase D were 39.5 +/- 0.1, 40.6 +/- 0.1 and 41.5 +/- 0.1 degree C for CD, HD and HH, respectively. Mean time to peak TREC was 9.3 +/- 1.1 (CD), 7.3 +/- 1.8 (HD) and 10.8 +/- 2.3 (HH) min and was not significantly different between conditions (P > 0.05). Heat dissipation amounted to 83 +/- 1, 73 +/- 2 and 70 +/- 1% of heat production in CD, HD and HH, respectively. Weight loss was significantly correlated with both body surface area (CD r = 0.85; HD r = 0.87; HH r = 0.81) and bodyweight (CD r = 0.97; HD r = 0.93; HH r = 0.94). The greatest weight loss recorded was 4.6% bodyweight in one horse in HD. The mean increase in exercise intensity over the whole CET (in terms of VO2) of HD and HH and HH compared with CD was 5 +/- 3 and 14 +/- 3% higher, respectively. The exercise induced hyperthermia and the reduced capacity for heat dissipation produced partial compensatory responses in minute ventilation (VE), particularly during Phase C, when the horses were trotting. In HD, the increase in VE was achieved mainly through an increase in frequency, whilst in HH it was achieved through an increase in tidal volume (VT). The horses demonstrated a high degree of tolerance to environmental heat load, suggesting a high thermoregulatory capacity. However, for unacclimatised animals exercising in severely hot and humid conditions, performance may be limited.     

Optimum Warranty Policies for Nonreparable Items

An approach is presented for establishing and evaluating warranty policies for products receiving renewable warranties when failure occurs during warranty. A general rebate model is described that allows total compensation to a consumer for failures during a fixed period and prorated compensation for a remaining interval of time. Associated warranty costs are weighed against the s-expected benefit to be derived from the program. Conditions for optimum warranty intervals are provided. Closed form results are given for exponentially and uniformly distributed failure times. The more complicated case of Weibull failure times is demonstrated by example. A sensitivity analysis of the parameters is included.     

Physiological responses of horses to a treadmill simulated speed and endurance test in high heat and humidity before and after humid heat acclimation

Food movements during complete feeding sequences on soft and hard foods (8 g of chicken spread, banana, and hard cookie) were investigated in 10 normal subjects; 6 of these subjects also ate 8 g peanuts. Foods were coated with barium sulfate. Lateral projection videofluorographic tapes were analyzed, and jaw and hyoid movements were established after digitization of records for 6 subjects. Sequences were divided into phases, each involving different food management behaviors. After ingestion, the bite was moved to the postcanines by a pull-back tongue movement (Stage I transport) and processed for different times depending on initial consistency. Stage II transport of chewed food through the fauces to the oropharyngeal surface of the tongue occurred intermittently during jaw motion cycles. This movement, squeeze-back, depended on tongue-palate contact. The bolus accumulated on the oropharyngeal surface of the tongue distal to the fauces, below the soft palate, but was cycled upward and forward on the tongue surface, returning through the fauces into the oral cavity. The accumulating bolus spread into the valleculae. The total oropharyngeal accumulation time differed with initial food consistency but could be as long as 8-10 sec for the hard foods. There was no predictable tongue-palate contact at any time in the sequence. A new model for bolus formation and deglutition is proposed.     

The Role and Therapeutic Potential of the Integrated Stress Response in Amyotrophic Lateral Sclerosis

In amyotrophic lateral sclerosis (ALS) patients, loss of cellular homeostasis within cortical and spinal cord motor neurons triggers the activation of the integrated stress response (ISR), an intracellular signaling pathway that remodels translation and promotes a gene expression program aimed at coping with stress. Beyond its neuroprotective role, under regimes of chronic or excessive stress, ISR can also promote cell/neuronal death. Given the two-edged sword nature of ISR, many experimental attempts have tried to establish the therapeutic potential of ISR enhancement or inhibition in ALS. This review discusses the complex interplay between ISR and disease progression in different models of ALS, as well as the opportunities and limitations of ISR modulation in the hard quest to find an effective therapy for ALS.     

Innovative Ozone/Oxygen Reactive Flotation for Paper Deinking

To improve paper recycling, the potential of an innovative deinking process using a reactive ozone/oxygen gas mixture instead of air was studied on two recovered paper furnishes (offset print and newsprint/magazine mixture). Using suitable O₃ concentrations, ink removal, following first-order kinetics, increased and losses dropped leading to better selectivity than using air alone. The ozone benefits in term of selectivity depended on temperature and paper furnishes and reached 100% for newsprint/magazine furnish at ambient temperature. Finally deinking effluent COD was significantly reduced and the ozone-based flotation allowed the reduction of the alkaline chemistry used before flotation.     

Priming Trait Inferences Through Pictures and Moving Pictures: The Impact of Open and Closed Mindsets.

A newly developed paradigm for studying spontaneous trait inferences (STI) was applied in 3 experiments. The authors primed dyadic stimulus behaviors involving a subject (S) and an object (O) person through degraded pictures or movies. An encoding task called for the verification of either a graphical feature or a semantic interpretation, which either fit or did not fit the primed behavior. Next, participants had to identify a trait word that appeared gradually behind a mask and that either matched or did not match the primed behavior. STI effects, defined as shorter identification latencies for matching than nonmatching traits, were stronger for S than for O traits, after graphical rather than semantic encoding decisions and after encoding failures. These findings can be explained by assuming that trait inferences are facilitated by open versus closed mindsets supposed to result from distracting (graphical) encoding tasks or encoding failures (involving nonfitting interpretations). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of bacille Calmette-Guérin vaccination on C-peptide secretion in children newly diagnosed with IDDM

OBJECTIVE: To determine whether administration of bacille Calmette-Guérin (BCG) vaccination to newly diagnosed IDDM patients can help preserve C-peptide secretion over the subsequent 18 months. RESEARCH DESIGN AND METHODS: Twenty-six IDDM patients, all of whom had been diagnosed within the previous year, had basal C-peptide levels >0.06 nmol/l, and had negative reactions to Mantoux's test, were randomized pairwise as they presented and were given either 0.1 ml (100 microg) BCG vaccine or 0.1 ml saline intradermally Both the patients and the investigators were blinded to the treatment. Fasting and glucagon-induced C-peptide levels and HbA1c were measured in all patients at enrollment and at 1, 3, 6, 9, 12, and 18 months after vaccination, and insulin dose was recorded at each visit. RESULTS: At enrollment, there was no significant difference in age, duration of diabetes, insulin dose, HbA1c, or fasting C-peptide levels between the BCG-vaccinated and control groups. The mean basal and stimulated C-peptide levels in the BCG-treated group did not differ significantly from those in the control group at any time during the 18 months of follow-up, and there was no difference in insulin dose or HbA1c at any time between the groups. CONCLUSIONS: BCG vaccination in children who have been recently diagnosed with IDDM does not affect the progressive decline in C-peptide levels or alter the clinical course of the disease.     

Signaled tailshock is perceived as similar to a stronger unsignaled tailshock: Implications for a functional analysis of classical conditioning.

24 water-deprived male Sprague-Dawley albino rats given fixed-electrode, variable-intensity tailshock at random times rated each trial by pressing either a "high-aversiveness" or "low-aversiveness" lever to obtain water. Trials on which a warning signal preceded tailshock resulted in more "high-aversiveness" leverpressing than did unsignaled trials. The magnitude of this effect varied as a function of factors including signal–shock interval, signal duration, and range and absolute value of shock intensities. Efforts to achieve a reversal of this effect were unsuccessful. Results suggest that the effect of the signal on lever choice was due largely to the aversiveness of the signal summating with the aversiveness of the tailshock. Hypotheses concerning factors that might have either masked or prevented classically conditioned preparatory responses elicited by the signal from reducing tailshock aversiveness were tested and rejected. Despite the greater aversiveness of the signaled condition, when given a choice of receiving or not receiving the signal, Ss displayed a preference for signaled tailshock. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)