Stability of High-Rate Anaerobic Systems. II: Fuzzy Stability Index

Based on a fuzzy logic method, fuzzy stability index N was proposed to integrate the complex information contained in various system variables and explicitly indicate the departure of a system from normal state. The instability of a system subjected to a shock could be explicitly revealed by its variance of N. Based on the examination of variance of N, the stability of three high-rate anaerobic reactors in the presence of various shocks was quantitatively compared. The comparison results based on N coincided in general with the conclusions obtained from a direct examination of the reactors' performance, but the N comparison method was proven to be much more convenient and explicit as compared with the method of direct examination of the reactors' performance.     

Performance enhancement of two-degree-of-freedom controllers via adaptive techniques

This paper generalizes earlier results on adaptive disturbance estimate (innovations) feedback regulation to the case of adaptive tracking, refining some of the techniques and formulations in the process. The adaptations proposed search within the class of all stabilizing two-degree-of-freedom controllers for a nominal plant and minimize a reference signal/disturbance rejection measure. The emphasis in the paper is on issues relevant to the tracking task and simulation results to demonstrate the effectiveness of the approach. The adaptive scheme is based on results concerning the convenient characterization of the class of all stabilizing two-degree-of-freedom controllers in terms of an arbitrary filter Q with a stable proper transfer function matrix Q(s). The fact that the closed-loop transfer matrices are affine in Q(s) permits a straightforward on-line least-squares update of the parameters of the filter Q on-line. The theory for the class of stabilizing controllers is used to set up appropriate signal preprocessing. The direct adaptive schemes proposed turn out to be recursive prediction error schemes which have local convergence properties. When convergent, they ensure enhancement of the performance of a fixed controller in other than the nominal plant case.     

Using the OPC standard for real-time process monitoring and control

In recent years, the use of software engineering tools for the process industry has increased substantially, accelerating research and development work. However, such tools are essentially limited in their connectivity to other systems and applications. It's therefore challenging to integrate the diverse, components developed using these tools so that they can seamlessly communicate locally and remotely. Accomplishing this integration is nonetheless essential, particularly as process control applications grow larger and more complex. We propose an open, nonproprietary, plug-and-play system (ONPS) for real-time process monitoring and control. Based on the object linking and embedding for process control (OPC) standard, ONPS provides a standard method for individual process monitoring and process control software to interact and share data.     

The effect of glycidyl methacrylate treatment of empty fruit bunch (EFB) on the properties of ultra‐violet radiation cured EFB‐unsaturated polyester composite

In this study, biofiber composites cured by ultra‐violet, were produced using pulp made from empty fruit bunch (EFB) as the reinforcing agent and unsaturated polyester as the matrix. The conversion of EFB fibers into pulp was carried out using organosolv pulping process. The EFB pulp was then chemically treated with glycidyl methacrylate (GMA) to different percentage of weight percent gain and the composites were made with different percentages of pulp loading. Results showed that the Kappa number of EFB decreased as the NaOH concentration in organosolv pulping increased. Composites which were made from GMA‐treated EFB showed better mechanical properties (tensile, flexural, and impact strength) than those of the unmodified. Fourier transform infrared spectroscopy showed peaks that proved the occurrence of grafting between GMA and OH from EFB pulp. Scanning electron microscope analysis showed the evidence of the enhancement of the compatibility between EFB and matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effects of rice husk (RH) particle size,glass fiber (GF) length,RH/GF ratio,and addition of coupling agent on the mechanical and physical properties of polypropylene‐RH‐GF hybrid composites

Polypropylene (PP) hybrid composites based on rice husk (RH) with different particle size and glass fiber (GF) with different length were prepared. The composites were subjected to mechanical and water immersion tests. From the results obtained, it was found that the mechanical properties of the hybrid composites were strongly dependent on the size of RH particle and length of GF. It could be further enhanced with the presence of coupling agent. In this study, two types of coupling agents, i.e., Epolene E‐43 (E‐43) and 3‐(trimethoxysilyl)‐propylmethacrylate (TPM), were employed. In general, E‐43 imparted significant improvement in the mechanical properties. From the water immersion results, it was found that the hydrophobicity of the composites was increased with the presence of coupling agent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

New protein PCiP from edible golden oyster mushroom (Pleurotus citrinopileatus) activating murine macrophages and splenocytes

A new immunomodulatory protein (PCiP) was purified from an edible golden oyster mushroom (Pleurotus citrinopileatus) by extraction with 5% (v/v) cold acetic acid in the presence of 0.1% (v/v) 2‐mercaptoethanol, followed by ammonium sulfate fractionation, DE‐52 and MonoQ anion‐exchange chromatography. Electrophoresis assays demonstrated that the molecular mass of PCiP was approximately 15.0 kDa and its pI was around 5.2. PCiP is a simple protein without carbohydrate, and cannot agglutinate mouse red blood cells, suggesting PCiP is not a lectin. In addition, PCiP (5–20 µg mL^?1) alone activated murine splenocytes, and markedly increased their proliferation and gamma‐interferon (IFN‐γ secretion, but suppressed MTT metabolization, while murine splenocytes were simultaneously stimulated by the mitogen concanavalin A (ConA). Furthermore, PCiP (5–20 µg mL^?1) directly activated murine macrophages and increased the production of both the nitric oxide (NO) and tumor necrosis factor‐alpha (TNF‐α by RAW 264.7 macrophages. These findings suggest that PCiP could strengthen both the innate and adaptive responses of its host. Copyright © 2007 Society of Chemical Industry