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31.
Data reconciliation is a well-known technique to improve accuracy and reliability of plant measurements. It relies on process models that could range from simple mass and energy conservation equations to complete causal dynamic models. Generally, precise estimates imply detailed plant models that could be difficult to build and update in practice. The trade-off between modeling efforts and estimation performances has thus lead to various approaches to deal with plant dynamics. The objective of the paper is to review and compare most common observers used for dynamic data reconciliation in the mineral and metallurgical processing industries. Comparisons are carried out using a separation unit and a flotation circuit as simulated benchmark plants. Observer performances are evaluated in terms of variance reduction. Strengths and weaknesses of the different methods are highlighted. Aspects such as estimation of model parameters, detection of gross errors, and handling of bilinear equations and plant non-linearities are discussed. 相似文献
32.
Masoud Haveshki Mahboobeh Mohamadhasani 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(12):2165-2173
The notion of extended filter of a filter associated to a subset of Rl-monoids is defined and related properties are investigated. Rachunek and Salounova proved that positive implicative filters and Boolean filters in Rl-monoids coincide with a condition in Rachunek and Salounova (Acta Univ Palacki Olomuc Fac rer nat Math 48(1):93–107, 2009). In this paper, we prove that positive implicative filters and Boolean filters coincide without any condition and get some results on various types of filters. 相似文献
33.
Amir Hossein NikoofardHossein Hajimirsadeghi Ashkan Rahimi-KianCaro Lucas 《Applied Soft Computing》2012,12(1):100-112
This paper presents a proposal for multiobjective Invasive Weed Optimization (IWO) based on nondominated sorting of the solutions. IWO is an ecologically inspired stochastic optimization algorithm which has shown successful results for global optimization. In the present work, performance of the proposed nondominated sorting IWO (NSIWO) algorithm is evaluated through a number of well-known benchmarks for multiobjective optimization. The simulation results of the test problems show that this algorithm is comparable with other multiobjective evolutionary algorithms and is also capable of finding better spread of solutions in some cases. Next, the proposed algorithm is employed to study the Pareto improvement model in two complex electricity markets. First, the Pareto improvement solution set is obtained for a three-player oligopolistic electricity market with a nonlinear demand function. Then, the IEEE 30-bus power system with transmission constraints is considered, and the Pareto improvement solutions are found for the model with deterministic cost functions. In addition, NSIWO algorithm is used to analyze this system with stochastic cost data in a risk management problem which maximizes the expected total profit but minimizes the profit risk in the market. 相似文献
34.
In in-vivo microsystems, one of the components is a biocompatible micropump in order to produce the necessary force to deliver
the fluid from the inlet to the outlet. In this contribution, a flexible micropump is fabricated which is aimed to be suitable
in drug delivery applications. It provides high degree of biocompatibility, since the only employed materials are implantation
grade polydimethylsiloxane elastomer and gold for the electrical interconnects. The working principle of the micropump is
based on transverse DC electroosmosis which is a new variant of conventionally applied high voltage DC electroosmosis. This
new technique is based on topography irregularities introduced in the channel resulting in a non-uniform charge distribution.
The advantage is to drive the micropump using a relatively low DC voltage of 10 V while getting an effective flow speed of
60 μm/s. In order to characterize the flow speed, dyed 3 μm beads are dispersed in the working fluid and their speed is measured
by the line scanning technique using a confocal microscope. It is also observed that the flow has a helical profile which
is an attractive feature for an efficient micro-mixer in active microfluidics and μ-TAS applications. 相似文献
35.
Mehdi Dehghan Masoud Hajarian 《International Journal of Control, Automation and Systems》2012,10(5):905-912
In this paper, an iterative algorithm is established for finding the generalized bisymmetric solution group to the coupled matrix equations (including the generalized (coupled) Lyapunov and Sylvester matrix equations as special cases). It is proved that proposed algorithm consistently converges to the generalized bisymmetric solution group for any initial generalized bisymmetric matrix group. Finally a numerical example indicates that proposed algorithm works quite effectively in practice. 相似文献
36.
37.
Azizli Mohammad Javad Barghamadi Mohammad Rezaeeparto Katayoon Mokhtary Masoud Parham Somayeh Darabi Mehdi Joker 《Iranian Polymer Journal》2021,30(10):1001-1018
Iranian Polymer Journal - Effects of graphene oxide (GO) on various properties of rubber hybrid nanocomposites based on PVMQ/XNBR-g-GMA/XNBR (phenyl-vinyl-methyl-polysiloxane/carboxylated nitrile... 相似文献
38.
Ghorbani-Choghamarani Arash Aghavandi Hamid Mohammadi Masoud 《Journal of Porous Materials》2021,28(4):1167-1186
Journal of Porous Materials - In this work, tris(hydroxymethyl)aminomethane-Zirconium complex supported on modified SBA-15 (SBA-15@n-Pr-THMAM-ZrO) prepared as a novel mesoporous catalyst. The... 相似文献
39.
Amir Mohammadzadeh Pter P. Lakatos Mihly Balogh Ferenc Zdor Dvid rpd Kardi Zoltn S. Zdori Kornl Kirly Anna Rita Galambos Szilvia Barsi Pl Riba Sndor Benyhe Lszl Kles Tams Tbi va Szk Laszlo G. Harsing Jr. Mahmoud Al-Khrasani 《International journal of molecular sciences》2021,22(5)
The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP. 相似文献
40.
Barimani Samaneh Amini Amir Chaharmahali Iman 《Journal of Computational Electronics》2021,20(3):1332-1342
Wave absorbers are considered to be fundamental building blocks for the manipulation of light. Almost all optical systems exploit absorbers to realize some functions. A highly tunable wide-band THz absorber is presented herein. Utilizing a dual-bias scheme with a single graphene layer leads to greater freedom to control the absorption response, while a conventional periodic array of graphene ribbons and a layer of graphene sheet are also exploited. Also, a circuit model representation for all the constituent parts of the proposed absorber is developed with an evolved design methodology. According to the simulation results, wide-band absorption from 3.5 to 6 THz is achieved.
相似文献