Advanced control of walking-beam reheating furnace

Rehearing furnace is an important device with complex dynamic characteristicsin steel plants. The temperature tracing control of reheating furnace has great importance both tothe quality of slabs and energy saving. A model-based control strategy, multivariable constrainedcontrol (MCC) for the reheating furnace control is used. With this control method, the furnace istreated as a six-input-six-output general model with loops coupled in nature. Compared with thetraditional control, the proposed control strategy gets better temperature tracing accuracy andexhibits some energy saving feature. The simulation results show that the performance of the furnaceis greatly improved.

Serum hepatic enzyme manifestations in patients with severe acute respiratory syndrome:Retrospective analysis

AIM: To evaluate the hepatic function in patients with severe acute respiratory syndrome (SARS) and possible causes of hepatic disorder in these patients. METHODS: One hundred and eighty-two patients with SARS were employed in a retrospective study that investigated hepatic dysfunction. Liver alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactic dehydrogenase (LDH) were analyzed in these patients. Patients with different hospital treatments were further investigated. RESULTS: Of the 182 patients, 128(70.3%) had abnormal ALT activity, 57(31.3%) had abnormal AST activity and 87(47.8%) had abnormal LDH activity. The peak of elevated hepatic enzyme activities occurred between the sixth day and the tenth day after the first day of reported fever. Of the 182 patients, 160(87.9%) had been treated with antibiotics, 137(75.2%) with Ribavirin, and 115(63.2%) with methylpredisolone. There was no statistically significant correlation between the duration of Ribavirin treatement and hepatic dysfunction. CONCLUSION: Abnormal liver functions were common in patients with SARS and could be associated with virus replication in the liver.

Predictive functional control of integrating process based on impulse response

The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significandy reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process.

Identification of a Ubiquitin-Binding Structure in the S-Locus F-Box Protein Controlling S-RNase-Based Self-Incompatibility

In flowering plants, self-incompatibility （SI） serves as an important intraspecific reproductive barrier to promote outbreeding. In species from the Solanaceae, Plantaginaceae and Rosaceae, S-RNase and SLF （S-locus F-box） proteins have been shown to control the female and male specificity of SI, respectively. However, little is known about structure features of the SLF protein apart from its conserved F-box domain. Here we show that the SLF C-terminal region possesses a novel ubiquitin-binding domain （UBD） structure conserved among the SLF protein family. By using an ex vivo system of Nicotiana benthamiana, we found that the UBD mediates the SLF protein turnover by the ubiquitin-proteasome pathway. Furthermore, we detected that the SLF protein was directly involved in S-RNase degradation. Taken together, our results provide a novel insight into the SLF structure and highlight a potential role of SLF protein stability and degradation in S-RNase-based self-incompatibility.