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Ohne Zusammenfassung 相似文献
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Ohne ZusammenfassungTeil einer bei der Naturwissenschaft-Philosophischen Fakultät der Technischen Hochschule Braunschweig eingereichten Dissertation. Referenten: Professor Dr. R. Iglisch und Prof. Dr. H-J. Kanold. Auch Herrn Dr. H. Eltermann bin ich für wertvolle Ratschläge zu Dank verpflichtet. 相似文献
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An analytical formula is obtained for the temperature dependence of the anisotropy parameter of the upper critical field of a two-band superconductor in the context of the generalized Ginzburg-Landau theory for layered superconductors. The theoretical results are compared with the experimental data for new superconductor LiFeAs. 相似文献
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Self-tuning fuzzy logic controllers (STFLC) for the active control of Marmara Kocaeli Earthquake excited crane structures
are studied in this paper. Vibration control using intelligent controllers, such as fuzzy logic has attracted the attention
of structural control engineers during the last few years, because fuzzy logic can handle, uncertainties and heuristic knowledge
and even non-linearities effectively and easily. The improved seismic control performance can be achieved by converting a
simply designed static gain into a real time variable dynamic gain through a self-tuning mechanism. A self-tuning fuzzy logic
controller is designed to reduce the vibrations of the crane structure. The simulated system has a five degrees-of-freedom
and modeled system was simulated against the ground motion of the Marmara Kocaeli Earthquake (M
w
=7.4) in Turkey on August 17, 1999. At the end of the study, the time history of the crane bridge and portal legs displacements,
accelerations, and frequency responses of the both uncontrolled and controlled cases are presented. Additionally, the performance
of the designed STFLC is also compared with a PD controller. Simulations of an earthquake excited bridge and portal legs are
performed to prove the validity of proposed control strategy. 相似文献
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Utility of the Pfitzinger Reaction in the Synthesis of Novel Quinoline Derivatives and Related Heterocycles
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Derviş Gök Rahmi Kasımoğulları Mustafa Cengiz Samet Mert 《Journal of heterocyclic chemistry》2014,51(1):224-232
2‐(2‐Amino‐3,5‐dinitrophenyl)‐2‐oxoacetic acid ( 2 ) was obtained from hydrolysis of 5,7‐dinitroisatin ( 1 ) in alkaline media. A novel quinoxaline derivative ( 3 ) was synthesized from the reaction of the same compound ( 1 ) with o‐phenylenediamine. Reacting 2 with ethyl 3‐oxo‐3‐phenylpropanoate yields 6,8‐dinitro‐2‐phenylquinoline‐3,4‐dicarboxylic acid ( 4 ). Then, 4 was converted into new quinoline‐diacylchloride, quinoline‐ester, quinoline‐dicarboxamide, pyridazine, and pyrroledione derivatives ( 5 , 6a , 6b , 6c , 6d , 7a , 7b , 7c , 7d , 8 , 9 , 10a , 10b , 10c , 10d , 11a , 11b , 12 ) with SOCl2, alcohols, amines, and hydrazines, respectively. The structures of synthesized compounds were clarified by 1H NMR, 13C NMR, IR, mass and elemental analysis methods. 相似文献
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In this paper, the dynamic behavior of a non-linear eight degrees of freedom vehicle model having active suspensions and a fuzzy logic (FL) controlled passenger seat is examined. The non-linearity occurs due to dry friction on the dampers. Three cases of control strategies are taken into account. In the first case, only the passenger seat is controlled. In the second case, only the vehicle body is controlled. In the third case, both the vehicle body and the passenger seat are fully controlled at the same time. The time responses of the non-linear vehicle model due to road disturbance and the frequency responses are obtained for each control strategy. At the end, the performances of these strategies are compared. 相似文献
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In this paper, the dynamic behaviour of a non-linear eight degrees of freedom vehicle model having active suspensions and passenger seat using Permanent Magnet Synchronous Motor (PMSM) controlled by a Neural Network (NN) controller is examined. A robust NN structure is established by using principle design data from the Matlab diagrams of system functions. In the NN structure, Fast Back-Propagation Algorithm (FBA) is employed. The user inputs a set of 16 variables while the output from the NN consists of f1–f16 non-linear functions. Further, the PMSM controller is also determined using the same NN structure. Various tests of the NN structure demonstrated that the model is able to give highly sensitive outputs for vibration condition, even using a more restricted input data set. The non-linearity occurs due to dry friction on the dampers. The vehicle body and the passenger seat using PMSM are fully controlled at the same time. The time responses of the non-linear vehicle model due to road disturbance and the frequency responses are obtained. Finally, uncontrolled and controlled cases are compared. It is seen that seat vibrations of a non-linear full vehicle model are controlled by a NN-based system with almost zero error between desired and achieved outputs. 相似文献