Adaptive control of a CSTR with a neural network model

An adaptive control algorithm with a neural network model, previously proposed in the literature for the control of mechanical manipulators, is applied to a CSTR (Continuous Stirred Tank Reactor). The neural network model uses either radial Gaussian or “Mexican hat” wavelets as basis functions. This work shows that the addition of linear functions to the networks significantly improves the error convergence when the CSTR is operated for long periods of time in a neighborhood of one operating point, a common scenario in chemical process control. Then, a quantitative comparative study based on output errors and control efforts is conducted where adaptive controllers using wavelets or Gaussian basis functions and PID controllers (IMC tuning with fixed parameters and self tuning PID) are compared. From this comparative study, the practicality and advantages of the adaptive controllers over fixed or adaptive PID control is assessed.     

Not supposed to feel this: Traditional masculinity in psychotherapy with male veterans returning from Afghanistan and Iraq.

Traditional masculine socialization presents challenges in psychotherapy, for example, by decreasing the likelihood of help-seeking and by making emotion-laden content more difficult to address. While this has been established in civilian populations, more intense forms of masculine socialization found in military settings may amplify such issues in male veteran populations. Male veterans returning from and Afghanistan (OEF) and Iraq (OIF) exhibit strong traditional masculine socialization and generally present in a unique manner. It is posited that OEF/OIF male veterans' unique presentation is in large part because of an interaction between high degrees of endorsement of traditional masculine gender role norms, relative youth, recency of distressing events, and recent experience in the social context of the military where traditional masculinity is reinforced. The impact of these variables on the psychotherapeutic process for male OEF/OIF veterans is significant and likely adds to ambivalence about change and increases dropout from psychotherapy. Modifications of traditional psychotherapeutic approaches designed to address traditional masculine gender role norms and their many interactions with other variables are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychosocial predictors of natural killer cell mobilization during marital conflict.

This study examined how specific emotions relate to autonomic nervous and immune system parameters and whether cynical hostility moderates this relationship. Forty-one married couples participated in a 15-min discussion about a marital problem. Observers recorded spouses' emotional expressions during the discussion, and cardiovascular, neuroendocrine, and immunologic parameters were assessed throughout the laboratory session. Among men high in cynical hostility, anger displayed during the conflict was associated with greater elevations in systolic and diastolic blood pressure, cortisol, and increases in natural killer cell numbers and cytotoxicity. Among men low in cynical hostility, anger was associated with smaller increases in heart rate and natural killer cell cytotoxicity. These findings suggest that models describing the impact of stress on physiology should be refined to reflect the joint contribution of situational and dispositional variables. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Turbulent Flow over Step with Rounded Edges: Experimental and Numerical Study

The study of turbulent flow over man-made obstacles and natural bed forms is an area of active research. This investigation was conducted to explore the differences between flow over a backward facing step and flow over a step with gradual transitions. Detailed measurements of longitudinal mean velocity and turbulence intensity were obtained using a one component LDV system. A turbulence-based numerical model was implemented to reproduce the measured flow variables and to explore additional flow characteristics, including Reynolds stresses and eddy viscosity. The separation that takes place in the rounded expansion plays a significant role in the flow pattern. In contrast to flow over a backward facing step, flow over a step with rounded edges shows a relatively shorter separation bubble and a slower return to the developed flow condition.     

Age and gender differences in oppositional behavior and conduct problems: A cross-sectional household study of middle childhood and adolescence.

Behavior problems among youths cannot be understood without explaining their age and gender differences, but age and gender differences cannot be explained until they have been accurately described. In a household survey of 1,285 youths aged 9 to 17 years, there were no gender differences in oppositional behavior, but aggression, property offenses, and status offenses were more common among boys. Levels of oppositional behavior were greater at younger ages, aggression peaked near the middle of this age range, and property and status offenses were more prevalent at older ages. These findings are generally consistent with developmental models of conduct problems but are inconsistent with a recent model of gender differences and raise questions about the external validity of current taxonomies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

WebBase: a repository of Web pages

In this paper, we study the problem of constructing and maintaining a large shared repository of Web pages. We discuss the unique characteristics of such a repository, propose an architecture, and identify its functional modules. We focus on the storage manager module, and illustrate how traditional techniques for storage and indexing can be tailored to meet the requirements of a Web repository. To evaluate design alternatives, we also present experimental results from a prototype repository called WebBase, that is currently being developed at Stanford University.     

The use of clozapine in the treatment of aggressive schizophrenia

The effect of coadministration of ritonavir and didanosine (ddI) on the pharmacokinetics of these drugs was investigated in a single-center, three-period, crossover study. Eighteen asymptomatic, HIV-positive men were assigned randomly to 6 different sequences of 3 regimens: ddI (200 mg every 12 hours) alone for 4 days, ritonavir (600 mg every 12 hours) alone for 4 days, and 4 days of ddI with ritonavir under dose-staggering conditions. Although not statistically significant, ritonavir concentrations were slightly higher on average (<10%) with concurrent administration of ddI compared with those of ritonavir alone. In contrast, ddI concentrations were lower with concurrent administration compared with those of ddI alone; maximum concentration and area under the concentration-time curve were reduced by about 15% (p < .05). The ddI elimination rate constant was unaffected by ritonavir, suggesting no change in ddI's systemic metabolism. Adverse events were similar between regimens. The relatively minor changes in ritonavir and ddI pharmacokinetics are probably not clinically relevant; therefore, dosage adjustment of either compound appears unnecessary when administered concurrently. However, the combination regimen of ddI and ritonavir continue to be evaluated clinically.     

3D solid modeling software development for industrial and academic purposes

This paper describes the main features of ADROS System: The 2D module DDC (Design and Drafting by Computer) and the 3D module SM (Solid Modeler).