Tian Y.,Nanjing Institute of Technology
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2017
Here, the vibration characteristics induced by full annular rub between carbon brushes and rotor in a generator were analyzed. According to carbon brushes' working principle, a rub force model was set up. The rub cross-section temperature field and the rotor's thermal bending model were built based on the theory of thermoelasticity. The rotor thermal bending model was coupled with the rotor FE dynamic model, and the system vibration responses were computed with the coupled model. Vibration characteristics were analyzed with a generator rotor model. Results showed that the rub between carbon brushes and the rotor can cause the system's spiral or divergent unstable vibration. The effects of unbalance force, carbon brushes-rotor non-concentricity and brushers' friction coeficient on the sytem vibration were studied. It was shown that unstable vibration can be eliminated through using more refined dynamic balance, increasing carbon brushes-rotor non-concentricity, or reducing brushers' friction coeficient. © 2017, Editorial Office of Journal of Vibration and Shock. All right reserved.
Nanjing Institute of Technology | Date: 2016-12-06
It relates to a high-power laser attenuator wherein laser is incident into an attenuator housing through a lens barrel; a wave plate, a first lens and a second lens are arranged in sequence on an incident light path along a laser incident direction; the wave plate can rotate around the incident light path, and normal lines of incident planes of the two lenses and the incident light axis are set to form a Brewster angle; a laser absorber assembly is arranged in a reflected light path of the first lens.
Chen L.,Nanjing Institute of Technology
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2011
The working principle of CT(Current Transducer) is introduced. Its mathematical model is built and its operating characteristics are analyzed with PSCAD /EMTDC, showing that the transient saturation is the main cause of CT error. According to the working principle of metering chip ADE7758, a simulation model of electronic energy meter is built and its simulative study is carried out based on the data measured in a traction substation, showing that the CT error induces larger energy measurement error, consistent with the theoretical analysis.
Liu C.-R.,Nanjing Institute of Technology |
Ding L.-H.,Nanjing Institute of Technology
Organic and Biomolecular Chemistry | Year: 2015
An unprecedented method to synthesise 3-sulfenylindoles is demonstrated via byproduct promoted sulfenylation of indoles with sulfinic acids in the absence of an external catalyst. The reaction selectively afforded structurally diverse indole thioethers in good to excellent yields in 1,2-dichloroethane at 80 °C. This journal is © The Royal Society of Chemistry 2015.
Sun M.,Nanjing Institute of Technology
Proceedings - 2010 2nd International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2010 | Year: 2010
Because request to quality of cold rolling sheet strip is higher and higher, the hydraulic AGC (Automatic Gauge Control) system has been a requisite means for improving quality of cold strip's finished products. But PID control strategy, being comprehensively used in the locale, is difficult to satisfy request of improving control precision of hydraulic AGC. Generalized predictive control (GPC) is one of predictive control theories. It needs few parameters, and adopts strategies of multi-step prediction, receding-horizon optimization and feedback correction, which has good tracking characteristic and reduces on-line calculations of control algorithm. So it's a kind of indispensable and practical strategy for exploring the application method of generalized predictive control. First, the direct algorithm of generalized predictive control was applied in the electro-hydraulic servo system of cold rolling mill, which adopted the stochastic gradient estimate algorithm to estimate parameters of controller on-line. It avoided on-line solving the Diophantine equation and reduced on-line calculation time. Based on the discrete controlled autoregressive integrated moving average (CARIMA) model, the control algorithm was combined with merits of adaptive control, which made control system possess of excellent robust and intelligent capability. At the same time, using for reference the thought of cascade control, generalized predictive control is combined in cascade structure. In the thickness loop of hydraulic AGC, it adopts PID control. And in the inner loop of screw-down servo system, it adopts generalized predictive control. It synthesizes merits of PID control, which possesses of easy algorithm, adjusting parameters conveniently and characteristic of generalized predictive control including of good tracking characteristic and strong robustness. The experimental result shows that adopted control strategies make system dynamic quality improved largely. Response time and control precision of screw-down servo system were improved. And the thickness precision of cold rolling strip was improved too. © 2010 IEEE.
Ling Y.,Nanjing Institute of Technology
Advances in Information Sciences and Service Sciences | Year: 2012
A new positioning algorithm of wireless sensor route is proposed with the combination ant colony algorithm and mobile agent technology. At first the algorithm adopts nodes movement estimated algorithm and judges the possible subnets to which the mobile node transfers in advance; then reserve resources in subnet in advance, and judge the possible subnet to which the mobile nodes add according to the movement direction; finally the optimized route is acquired by adopting improved ant colony algorithm seeking system. In this way not only the limited bandwidth and power of wireless sensor network could be saved, but the issue that it is difficult to provide QoS security due to subnet switch could be solved. The simulation test indicates the proposed method could improve the resource utility for sensor network, decrease redundant data transfer efficiently, decrease communication consumption and propone the life cycle of network.
Zhu Q.,Ningbo University |
Song B.,Nanjing Institute of Technology
Nonlinear Analysis: Real World Applications | Year: 2011
This paper is concerned with the problem of exponential stability for a class of impulsive nonlinear stochastic differential equations with mixed time delays. By applying the LyapunovKrasovskii functional, Dynkin formula and Razumikhin technique with a stochastic version as well as the linear matrix inequalities (LMIs) technique, some novel sufficient conditions are derived to ensure the exponential stability of the trivial solution in the mean square. The obtained results generalize and improve some recent results. In particular, our results are expressed in terms of LMIs, and thus they are more easily verified and applied in practice. Finally, a numerical example and its simulation are given to illustrate the theoretical results. © 2011 Elsevier Ltd. All rights reserved.
Hong B.,Nanjing Institute of Technology |
Lu D.,Jiangsu University
Mathematical and Computer Modelling | Year: 2012
In this paper, an improved general mapping deformation method based on the generalized Jacobi elliptic functions expansion method with computerized symbolic computation is used to construct more new exact solutions of a generalized KdV equation with variable coefficients. As a result, seven families of new generalized Jacobi elliptic function-like solutions, soliton-like solutions and trigonometric function solutions of the equation are obtained by using this method, which shows that the general method is more powerful and will be used in further works to establish more entirely new solutions for other kinds of nonlinear partial differential equations arising in mathematical physics. © 2011 Elsevier Ltd.
Nanjing University and Nanjing Institute of Technology | Date: 2015-07-13
Implementations herein relate to systems and methods for removal of tebuconazole from water using a duplex reactor. Water samples containing tebuconazole enter a double sandwich of the duplex reactor, and then enter a reactor inner shell of the duplex reactor through a water distributor. In the duplex reactor, the tebuconazole is removed by adsorption resins loaded with microorganisms. After the removal, a concentration of the tebuconazole in adsorption effluent is below the standard limit of the national pesticide wastewater discharge. The microorganisms loaded on the resins use organic carbon (e.g., tebuconazole) in water as a carbon source and degrade tebuconazole that is absorbed by the resins. The systems and methods not only solve problems associated with conventional techniques (e.g., poor water quality fluctuations and lacking of time long degradation), but also address issues associated with resin adsorption methods (e.g., secondary pollution derived from resins regeneration).
Nanjing University and Nanjing Institute of Technology | Date: 2013-03-27
An efficient combined advanced treatment method of electroplating wastewater is disclosed, which belongs to the technical field of electroplating wastewater treatment. The method includes: after pretreatments including cyanide breaking, dechromisation and coagulating sedimentation, introducing the electroplating wastewater to a contact oxidation tank for biochemical treatment, and settling the effluent from the contact oxidation tank down in an inclined pipe of a secondary sedimentation tank to realize the separation of the sludge from water; charging the effluent to a coagulating sedimentation tank, and undergoing coagulating sedimentation with the aid of a flocculant and a coagulant aid added; feeding the effluent, as an influent, to a resin adsorption tank for adsorption with a magnetic resin; and after passing through a filter, flowing the effluent after adsorption to a fixed bed resin adsorption unit, so as to realize the discharge up to standard and recycle of the effluent.