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Performance assessment of PID and IMC tuning methods for a mixing process with time delay 总被引:1,自引:0,他引:1
A flow process with time delay has been considered for modeling and control. A dilute solution of sodium chloride is used as tracer and an online conductivity measurement unit as sensor and recorder. The objective of the current study is to design control algorithms and present corresponding robust control analysis for the process. The control methodologies considered are (i) conventional PID control and (ii) internal model control (IMC). The control structures are comparatively analyzed using standard robustness measures for stability and performance. Of the two control algorithms, conventional PID and IMC, IMC exhibits faster settling time, no overshoot, better set-point tracking and disturbance rejection, and good robust performance than the PID control scheme. 相似文献
84.
Mobile Networks and Applications - In big data, the information retrieval (IR) embraces the discovery of documents from a compilation of dataset which are related to the user query. Usually, the... 相似文献
85.
Sashka Dimitrievska Juan Wang Tylee Lin Amanda Weyers Hualong Bai Lingfeng Qin Guangxin Li Chao Cai Alan Kypson Nina Kristofik Ashley Gard Sumati Sundaram Kota Yamamoto Wei Wu Liping Zhao Mehmet H. Kural Yifan Yuan Joseph Madri Themis R. Kyriakides Robert J. Linhardt Laura E. Niklason 《Advanced functional materials》2020,30(23)
Novel biological vascular conduits, such as decellularized tissue engineered vascular grafts (TEVGs) are hindered by high thrombogenicity. To mimic the antithrombogenic surface of native vessels with a continuous glycosaminoglycan layer that is present on endothelial cells (ECs), a hyaluronic acid (HA) modified surface is established, to effectively shield blood platelets from collagen‐triggered activation. Using the amine groups present on 4 mm diameter decellularized TEVGs, a continuous HA hydrogel coating is built via a bifunctional thiol‐reactive cross‐linker, thereby avoiding nonspecific collagen matrix cross‐linking. The HA hydrogel layer recreates a luminal wall, “hiding” exposed collagen from the bloodstream. In vitro blood tests show that adhered platelets, fibrinogen absorption, and fibrin formation on HA‐coated decellularized TEVGs are significantly lower than on uncoated decellularized TEVGs. The HA surface also inhibits macrophage adhesion in vitro. HA‐coated decellularized syngeneic rat aortae (≈1.5 mm diameter), and TEVGs in rat and canine models, respectively, are protected from aggressive thrombus formation, and preserve normal blood flow. Re‐endothelialization is also observed. HA‐coated TEVGs may be an off‐the‐shelf small‐diameter vascular graft with dual benefits: antithrombogenic protection and promotion of endothelium. 相似文献
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S. Kalyana Sundaram S. Jayabal N.S. Balaji G. Bharathiraja 《Advanced Composite Materials》2018,27(1):107-117
This investigation is focused on identifying a new variety of natural fiber (Dharbai fiber) for reinforcement in polymer matrix composites. An investigation on extraction procedure of Dharbai fibers has been undertaken. The chemical properties of Dharbai fibers were determined experimentally as per TAPPI standards. The FT-IR Spectroscopy was used to study the chemical structure of Dharbai fibers and the tensile properties of these fibers were studied using single filament test. The fibers extracted were reinforced in polyester matrix by varying the fabrication parameters namely fiber weight content (%) and fiber length (mm). The effect of fiber weight content and fiber length on the mechanical properties of Dharbai fiber-polyester composites were evaluated as per ASTM standards. Scanning electron microscope was used to characterize the interfacial bonding between Dharbai fibers and polyester matrix. This study confirmed that, the Dharbai fibers could be used as an effective reinforcement material for making low load bearing polymer composites. 相似文献
88.
Kaya Demir Vijay Sukumaran Yoichiro Sato Abderrahim El Amrani Koushik Ramachandran Raghuram Pucha P. Markondeya Raj Venkatesh Sundaram Rao Tummala 《Journal of Materials Science: Materials in Electronics》2018,29(15):12669-12680
Glass is an ideal substrate material to enable 2.5D and 3D packaging of ICs at low cost and high performance. However, it is a brittle material and is prone to failures during fabrication and operation. Large coefficient of thermal expansion (CTE) mismatch between copper and glass leads to thermomechanical stresses that can lead to glass cracking and delamination from glass interfaces. This paper focuses on modeling and reliability characterization of copper-plated through-package-vias (TPV) in glass packages. Thermomechanical simulations were carried out to obtain design guidelines for reliable TPVs in glass. Test-vehicles with different glass thicknesses and copper TPV fabrication conditions were fabricated for thermal cycling tests, resistance monitoring and failure analysis. The reliability characterization results showed good thermomechanical reliability of TPVs in ultra-thin glass panels. 相似文献
89.
R. Ganapathi Sundaram M. Thamaraiselvi G. Vengatesh M. Sundaravadivelu 《Journal of Failure Analysis and Prevention》2018,18(5):1168-1180
The inhibition performance and surface protection of green corrosion inhibitor 8-quinoline sulphonyl chloride (8QSC) on copper (Cu) was evaluated by chemical (weight loss) method in 0.5, 1.0 and 2.0 M HNO3 solutions and by electrochemical methods such as potentiodynamic polarization (PDP), AC-impedance spectroscopy (AC-IS) and linear polarization resistance in 1.0 M HNO3 solution at room temperature. Both chemical and electrochemical techniques showed that 8QSC is an efficient green corrosion inhibitor for copper and the efficiency reached 90.4% by weight loss method and 88.4% by AC-IS method at optimum concentration of (300 ppm) 8QSC. The adsorption behavior of 8QSC on copper metal in acid medium obeyed the Langmuir isotherm. The thermodynamic parameters of the adsorption processes were calculated and discussed. AC-IS technique exhibits one capacitive loop, indicating that the corrosion reaction was controlled by charge transfer process. The PDP curves revealed that 8QSC acts as a mixed-type inhibitor. Protective layer of 8QSC on copper surface was examined by SEM, AFM and FT-IR techniques. The experimental results corroborated with results obtained from theoretical DFT studies. 相似文献
90.
Manibalan Gunasekaran Murugadoss Govindhasamy Marimuthu Rajendiran Rajabathar Jothi Ramalingam Kumar Manavalan Rajesh 《Journal of Materials Science: Materials in Electronics》2022,33(9):6592-6602
Journal of Materials Science: Materials in Electronics - In this present research, heterostructure NiO–SnO2 nanocomposite modified electrode was developed to determine l-cysteine molecule.... 相似文献