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1.
There has been a growing interest in combining both neural network and fuzzy system, and as a result, neuro-fuzzy computing techniques have been evolved. ANFIS (adaptive network-based fuzzy inference system) model combined the neural network adaptive capabilities and the fuzzy logic qualitative approach. In this paper, a novel structure of unsupervised ANFIS is presented to solve differential equations. The presented solution of differential equation consists of two parts; the first part satisfies the initial/boundary condition and has no adjustable parameter whereas the second part is an ANFIS which has no effect on initial/boundary conditions and its adjustable parameters are the weights of ANFIS. The algorithm is applied to solve differential equations and the results demonstrate its accuracy and convince us to use ANFIS in solving various differential equations. 相似文献
2.
Ali Madady Hamid-Reza Reza-Alikhani Sara Zamiri 《International Journal of Control, Automation and Systems》2018,16(5):2187-2202
One of the most important problems in the field of the iterative learning control (ILC) is to design algorithms, in order to achieve a desired convergence rate. In this paper a new type of the ILC algorithm is introduced, which is called N-parametric type ILC with optimal gains. The convergence of the proposed algorithm is analyzed and an optimal design method is presented to determine its gains. The effect of the number of the parameters on the convergence rate of the presented ILC is investigated. It is shown that N parametric type of this ILC has a better performance than the N-1 one. Illustrative simulation examples are given to verify the theoretical analysis. 相似文献
3.
Hamid-Reza Kohan-Ghadr Brooke Armistead Mikaela Berg Sascha Drewlo 《International journal of molecular sciences》2021,22(20)
Irisin is a newly discovered exercise-mediated polypeptide hormone. Irisin levels increase during pregnancy however, women with preeclampsia (PE) have significantly lower levels of Irisin compared to women of healthy pregnancies. Even though many studies suggest a role of Irisin in pregnancy, its function in the human placenta is unclear. In the current study, we aimed to understand key roles of Irisin through its ability to protect against apoptosis is the preeclamptic placenta and in ex vivo and in vitro models of hypoxia/re-oxygenation (H/R) injury. Our studies show that Irisin prevents cell death by reducing pro-apoptotic signaling cascades, reducing cleavage of PARP to induce DNA repair pathways and reducing activity of Caspase 3. Irisin caused an increase in the levels of anti-apoptotic BCL2 to pro-apoptotic BAX and reduced ROS levels in an in vitro model of placental ischemia. Furthermore, we show that Irisin treatment acts through the Akt signaling pathway to prevent apoptosis and enhance cell survival. Our findings provide a novel understanding for the anti-apoptotic and pro-survival properties of Irisin in the human placenta under pathological conditions. This work yields new insights into placental development and disease and points towards intervention strategies for placental insufficiencies, such as PE, by protecting and maintaining placental function through inhibiting hypoxic ischemia-induced apoptosis. 相似文献
4.
A selective method for the determination of thorium (IV) using an optical sensor is described. The sensing membrane is prepared by immobilization of thorin–methyltrioctylammonium ion pair on triacetylcellulose polymer. The sensor produced a linear response for thorium (IV) concentration in the range of 6.46 × 10?6 to 9.91 × 10?5 mol L?1 with detection limit of 1.85 × 10?6 mol L?1. The regeneration of optode was accomplished completely at a short time (less than 20 s) with 0.1 mol L?1 of oxalate ion solution. The relative standard deviation for ten replicate measurements of 2.15 × 10?5 and 8.62 × 10?5 mol L?1 of thorium was 2.71 and 1.65%, respectively. The optode membrane exhibits good selectivity for thorium (IV) over several other ionic species and are comparable to those obtained in case of spectrophotometric determination of thorium using thorin in solution. A good agreement with the ICP-MS and spiked method was achieved when the proposed optode was applied to the determination of thorium (IV) in dust and water samples. 相似文献
5.
Mojtaba Movahedi Amir-Hossein Kokabi Hamid-Reza Madaah-Hosseini Mahdi Kiani 《Metals and Materials International》2011,17(4):665-670
In the present study, the roll bonding behaviour of Al-3003/Al-4043 and Al-3003/Zn sheets were compared. The bi-layer sheets
were produced by a roll bonding process at different reductions in thickness and rolling temperatures. The joint strengths
of the sheets were evaluated by peel and bend testing before and after supplemental annealing treatment. The peeled surfaces
were examined using a scanning electron microscope. The results indicated that the Al-3003/Al-4043 sheets were bonded with
higher joint strength and lower threshold reductions in thickness with respect to the Al-3003/Zn sheets. In contrast to the
Al-3003/Zn sheets, significant improvement was observed in the joint strength of the Al-3003/Al-4043 sheets after annealing
treatment. Moreover, electron microscopy examinations showed that the fracture types of the Al-3003/Al-4043 and Al-3003/Zn
sheets were predominantly ductile and brittle, respectively. 相似文献
6.
Wastewater treatment with bacteria immobilized onto a ceramic carrier in an aerated system 总被引:1,自引:0,他引:1
Kariminiaae-Hamedaani HR Kanda K Kato F 《Journal of Bioscience and Bioengineering》2003,95(2):128-132
Biological treatment of the wastewater discharged from a food processing factory was continuously carried out in a packed bed bioreactor under aerobic conditions. The bacterium isolated from the wastewater was immobilized onto a new type of ceramic carrier by a vacuum method and high numbers of bacteria were colonized onto the carrier (2.9 x 10(9) cfu/g of dry ceramic carrier). The effect of the hydraulic retention time (HRT) and aeration rate on the removal of the chemical oxygen demand (COD) was investigated. The system was able on average to remove more than 82% of the influent COD during 160 d of operation and more than 87% of the influent COD on average was removed when the HRT was 30.17 h and the aeration rate was 2.0 vvm. Aeration rates in the range of 0.4 to 2.0 vvm do not affect the COD removal efficiency. 相似文献
7.
Afshin Mehrsai Hamid-Reza Karimi Bernd Scholz-Reiter 《The International Journal of Advanced Manufacturing Technology》2013,64(5-8):1131-1150
Nowadays, material planning and control strategies are becoming continuously complex tasks spanning from individual plants to logistic networks. In fact, this is the consequence of increasing intricacy in product variants and their respective convolution in networks’ structures. Customers ask for specific products with individual characteristics that force companies for more clever performances by more flexibility. For doing so, the existing planning and control systems, which work based on central monitoring and controlling, show some limitations for organizing every operation on time or in the right time. Therefore, in the recent decade, a great attention is put on decentralized control and, to some extent, autonomy. This paper tries to investigate the possibility of combining this new research paradigm with existing strategies in production logistics, in order to improve material handling and control task according to material flow criteria. To show this, an exemplary plant after decoupling point out of a logistic network is considered for simulation and analysis. This combines Conwip system with learning autonomous pallets’ concept in a discrete event simulation model. Several decentralized control scenarios are experimented and compared together. Here, the learn methodology is brought to pallets based on fuzzy rules and advantage of closed loop systems. 相似文献
8.
Due to the consumption of chicken and chicken products in Turkey at high ratio, trace metal content of chicken and chicken products from Turkey were determined by atomic absorption spectrometry after microwave digestion. The accuracy of the method was confirmed by analysis of standard reference material (NIST SRM 1577b Bovine liver). Trace element content in various parts of chicken samples and chicken products were to be in the range of 0.10-114 microg/g for copper, 0.25-6.09 microg/kg for cadmium, 0.01-0.40 microg/g for lead, 0.10-0.91 microg/g for selenium, 0.05-3.91 microg/g for manganese, 0.06-0.10 microg/g for arsenic, 0.01-0.72 microg/g for chromium, 0.01-2.08 microg/g for nickel, 0.01-0.02 microg/g for cobalt, 0.10-1.90 microg/g for aluminium, 1.21-24.3 microg/g for zinc, 2.91-155 microg/g for iron. The levels of lead in some analyzed chicken products were higher than the recommended legal limits for human consumption. 相似文献
9.
A new method using a mini-column packed with sulfur as a new solid phase extractor has been developed for simultaneous preconcentration of lead and cadmium in water samples prior to flame atomic absorption spectrometric determinations. The effects of various parameters such as pH, flow rate of sample and eluent, type and concentration of eluent, sample volume, amount of adsorbent and interfering ions have been studied. The calibration graph was linear in the range of 10-300 and 1-20 ng mL(-1) for lead and cadmium, respectively. The limit of detection based on three times the standard deviation of the blank (3S(b)) was 3.2 and 0.2 ng mL(-1) (n=10) for lead and cadmium, respectively. A preconcentration factor of 250 was achieved in this method. The proposed procedure was applied to the determination of metal ions in tap, river and wastewater samples. 相似文献
10.
Performance of IEEE 802.15.4 Clusters with Power Management and Key Exchange 总被引:1,自引:0,他引:1
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The IEEE 802.15.4 specification is a recent low data rate wireless personal area network standard.While basic security services are provided for,there is a lack of more advanced techniques which are indispensable in modern personal area network applications.In addition,performance implications of those services are not known.In this paper,we describe a secure data exchange protocol based on the ZigBee specification and built on top of IEEE 802.15.4 link layer.This protocol includes a key exchange mechanism.We assume that all nodes are applying power management technique based on the constant event sensing reliability required by the coordinator.Power management generates random sleep times by every node which in average fairly distributes the sensing load among the nodes.Key exchange is initiated by a cluster coordinator after some given number of sensing packets have been received by the coordinator.We develop and integrate simulation model of the key exchange and power management technique into the cluster's reliable sensing function.We evaluate the impact of security function and its periodicity on cluster performance. 相似文献