Enhanced-PID Control Based Antagonistic Control For Pneumatic Artificial Muscle Actuators

Pneumatic artificial muscle (PAM) is a rubber tube clothed with a sleeve made of twisted fiber-code, and is fixed at both ends by fixture. It has a property like a spring, which enables it to change its own compliance by the inner air pressure. The advantages of pneumatic system such as high power-to-weight ratio, compactness, ease of maintenance, inherent safety and cleanliness led to the development of McKibben muscle and PAM actuators. However, the drawbacks of PAM, for example, the air compressibility and the lack of damping ability of PAM bring dynamic delay to the pressure response and cause oscillatory motion to occur. It is not easy to realize the PAM motion with high accuracy and high speed due to all the non-linear characteristics of pneumatic mechanism. In this thesis, an antagonistic-based PAM system is designed and presented. Two identical PAM actuators are connected in parallel and vertical direction which imitate the human biceps-triceps system and emphasize the analogy between the artificial muscle and human skeletal muscle behavior. Some past control algorithms on the positioning control of PAM mechanisms are discussed. In this thesis, a practical control method, namely enhanced-PID controller is proposed to control the trajectory motion of the PAM actuators. The development and modeling of the experiment setup are explained, followed by the driving characteristics of the PAM system. Two simple and straight forward steps are demonstrated as the design procedures of the enhanced-PID controller. The control structure of the proposed controller consists of a PID element, Compensator A and Compensator B. The effectiveness of the proposed control algorithm is validated in sinusoidal continuous motion. The tracking performance of the enhanced-PID controller is compared with a classic PID controller, showing that the control performance of the enhanced-PID controller is satisfactory and better in dealing with highly non-linear PAM system

Improved testing characterization on radio frequency connector in calibration system

For extending the dynamic range of measuring equipment, radio frequency connectors are found in a wide variety of electronic types of equipment. An important part of characterizing RF microwave circuits and devices required precision in S-parameters measurement. Variety type of dimension and frequency range can be found with RF connector. The main issue is the RF connector neglects the insertion loss causing an unknown error contributed to an RF system in calibration. The unknown insertion loss could create a phenomenon that triggered a false failure in the RF system. The objective of this study is to develop and calculate the Error normalize ratio for characterizing RF connectors, identify the unique RF connector characterization process and techniques associate with measurement uncertainty calculation by using the vector network analyzer, and integrate the power sensor calibration system with RF connector mismatch into the component of the calculation. This is to determine the methodology into several effective techniques of RF connector insertion loss, port match, measurement uncertainty, decision rule to a newly developed product specification in an RF manufacturing process into a power sensor calibration system as the final product to the end customer. In addition, the method applied in this study refers to the international requirements example ANSI/NCSL Z540.3 released in the year 2006, ISO/IEC 17025:2017 released in the year 2017, and ISO GUM (JCGM 100:2008) released in the year 2008 to meet the quality results. The expected outcome of this study would provide a summary of RF connector mismatch is extremely important to an RF measurement system that required extensive research by applying appropriate equipment in precision measurement

THE ETHNICITY ENIGMA: UNRAVELLING THE DIETARY, METABOLIC AND PHYSIOLOGICAL DIFFERENCES

Ph.DDOCTOR OF PHILOSOPH

Combination of anti-C1qA08 and anti-mCRP a.a.35-47 antibodies is associated with renal prognosis of patients with lupus nephritis

ObjectiveThe aim of this study is to explore the prevalence and clinicopathological associations between anti-C1qA08 antibodies and anti-monomeric CRP (mCRP) a.a.35-47 antibodies and to explore the interaction between C1q and mCRP.MethodsNinety patients with biopsy-proven lupus nephritis were included from a Chinese cohort. Plasma samples collected on the day of renal biopsy were tested for anti-C1qA08 antibodies and anti-mCRP a.a.35-47 antibodies. The associations between these two autoantibodies and clinicopathologic features and long-term prognosis were analyzed. The interaction between C1q and mCRP was further investigated by ELISA, and the key linear epitopes of the combination of cholesterol binding sequence (CBS; a.a.35-47) and C1qA08 were tested by competitive inhibition assays. The surface plasmon resonance (SPR) was used to further verify the results.ResultsThe prevalence of anti-C1qA08 antibodies and anti-mCRP a.a.35-47 antibodies were 50/90 (61.1%) and 45/90 (50.0%), respectively. Levels of anti-C1qA08 antibodies and anti-mCRP a.a.35-47 antibodies were negatively correlated with serum C3 concentrations ((0.5(0.22-1.19) g/L vs. 0.39(0.15-1.38) g/L, P=0.002) and (0.48(0.44-0.88) g/L vs. 0.41(0.15-1.38) g/L, P=0.028), respectively. Levels of anti-C1qA08 antibodies were correlated with the score of fibrous crescents and tubular atrophy (r=-0.256, P=0.014 and r=-0.25, P=0.016, respectively). The patients with double positive antibodies showed worse renal prognosis than that of the double negative group (HR 0.899 (95% CI: 0.739-1.059), P=0.0336). The binding of mCRP to C1q was confirmed by ELISA. The key linear epitopes of the combination were a.a.35-47 and C1qA08, which were confirmed by competitive inhibition experiments and SPR.ConclusionThe combination of anti-C1qA08 and anti-mCRP a.a.35-47 autoantibodies could predict a poor renal outcome. The key linear epitopes of the combination of C1q and mCRP were C1qA08 and a.a.35-47. A08 was an important epitope for the classical pathway complement activation and a.a.35-47 could inhibit this process

Downstream Impact Investigation of Released Sediment from Reservoir Desilting Operation

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive