Abstract: In this paper we mainly use the SCR system to do some ESC experiments for reducing NOx emissions. The main purpose of the experiments is to improve the ability of SCR system to reduce NOx emissions. The main research works are focused on the following aspects: First we could get the NOx emissions content for original machine and the theoretical demand content for urea by the emission experiment of original machine. Then on the condition of SCR catalyst is not installed, we could get the NOx emissions content by injecting a certain amount of urea. Based on the above experiments we could get the experimental results for NOx emissions by installing SCR catalyst and using the DCU to control urea injecting.
Abstract: Charge coupled device has many merits, which makes it to measure bullet parameters possible. This article starts with possibility of testing based on charge coupled device, then introduces the completed processing methods and algorithms, finally based on Matlab’s GUI, methods and algorithms integrated, through input parameters, the calculated result is seen immediately before you. This way has characteristic of simplicity and convenience. In order to make this testing system much easier and use convenient, Matlab’s GUI is used to obtain the aim. It can conclude that this testing system is very utility in test field.
Abstract: Roundness error is widely measured in machinery industry, but existing roundness error measuring instruments have much weakness such as single function and low intelligent level, etc. Aimed at the shortage of traditional roundness error measuring instruments, the roundness error measuring system based on virtual instrument is developed. This system which takes NI LabVIEW8.5 as development platform, evaluates roundness error with the least square method, adopts modular design, combines with 610H IPC, PCI-1716 data acquisition card, stepping motors, LVDT sensor and other hardware can realize fast, precise measurement of roundness error of shaft parts. It is verified to be feasible by measuring standard parts. Compared with the similar product, this system has many advantages such as simple operation, intuitive display, high intelligent level and so on.
Abstract: At present, the development of smart grid has already formed a consensus in the world. As an energy depletion big country, the development of smart grid has very important significance in China. Transformer substation plays a very important role in the smart grid, so do semantic description of substation equipment and improve their interoperability can effectively raise the intelligence application of the transformer substation. The ontology technology based on semantic sharing has unique advantages in describing the concept and relationship. Therefore, to build up ontology for substation equipment and to describe it using the ontology description language-OWL can achieve power equipment information sharing, interaction and processing, which provides a new method to build smart grid.
Abstract: Due to the natural disasters, the transmission line fault has randomness. In order to describe the uncertainty of the transmission line fault, the conditional value-at-risk (CVaR) theory is introduced to quantify the uncertainty risk caused by transmission line failure. A stochastic optimal dispatch model of the power system considering the security risk constraint is proposed in this paper, using the sample average approximation (SAA) method and the analytic method to solve the model. The influence on the result of stochastic optimization dispatching is analysed by different conditional value at risk and confidence levels. The simulations demonstrate that the stochastic optimal dispatch model considering the security risk constraint is reasonable and provides a theoretical basis for the stochastic optimization dispatching of the power system considering line failure.
Abstract: In order to investigate whether magnetic field can improve the seawater desalination efficiency, the influence of magnetic field on the aqueous solutions of NaCl is studied by molecular dynamics (MD) simulations. The results show that, under the influence of magnetic field, the hydration number of Cl- ions increases and the mobility of hydrated Cl- ions is weakened, while the mean size of water clusters decreases and the mobility of water molecules is enhanced. These may lead to higher salt rejection and water flux by the usage of magnetic field in our novel desalination method based on rotating electromagnetic effect.
Abstract: Evaluation of leather handle property is always a focus question all over the world. HEM method is widely used to evaluate leather handle property nowadays. In this easy, PNN neural network was used as a new method to evaluate leather handle property. At first, basic theory about PNN neural network was briefly introduced. Second, PNN neural network mathematical model for leather handle property evaluation was set up after the mechanical characteristics parameters were selected. Process of PNN neural network designing and Matlab program were given. Third, the ability of PNN neural network to classify leather rank was proofed through program training and sample testing. The result is precise and it indicates that PNN neural network mathematical model has important practical and theory value.
Abstract: V2G technology achieves a two-way interaction of the grid and electric vehicles (EVs), it makes plug-in hybrid electric vehicle (PHEV) be able to access grid and participate in grid scheduling. By V2G technology, PHEVs can provide FM and spinning reserve ancillary services such as economic dispatch. With the extensive use of plug-in hybrid electric vehicles (PHEVs), its important impact on charge and discharge process will be the grid safe and economic operation. Firstly, the article proves the V2G discharge capacity of a normal distribution from the theory, and based on which to establish a stochastic economic dispatch model. The results which obtain by using the IEEE 14 node system simulation show that this conclusion of the constructed model is feasible and effective, and the conclusions that the V2G node optimal active output power and minimum scheduling cost expectations are proportional to the the V2G discharge capacity expectations are also obtained.
Abstract: Accident investigation is critical to the success of an effective safety program. The causes of the accidents have to be determined. A proper accident investigation report will also lead to a proper determination of whether an accident was preventable or not. The purpose of this study is to adopt the advantages from aircraft accident investigation report format. The prudent report format of accident is to enhance system and system safety. This study emphasizes the importance and necessity of element through studying an accidental investigation report. The results indicate that the conclusions to be raised and the forms of safety recommendations are best in all situations.
Abstract: This paper deals with the reentry trajectory optimization problem for lunar return with consideration of entry vehicle’s fore-body shape. Three performance objectives are applied in this work: cross range, peak heat flux and total heat load. Aerothermodynamic models are based on modified Newtonian impact theory and semi-empirical correlations for convective and radiative stagnation-point heat transfer. A population based evolutionary algorithm has been executed to optimize the multidisciplinary problem. At last the numerical example showed the Pareto frontiers for spherical segment and sphere cone respectively, one of optimal trajectory designs selected from the Pareto frontiers are showed in this paper. The mission requirements are satisfied through the aerothermodynamic balance.