Strengthening the risk management of equipment maintenance costs is of great significance for military units to cope with the funding management and formulate relative responsive measures.Firstly,aiming at the deficiency of the current research theory and method of risk supervision over e-quipment maintenance fee,the hierarchical holographic modeling method was applied to identify risk factors in the procedure,starting from the perspective of unit supervision.Secondly,game theory was used to find the optimal index combination weight between subjective and objective weighting me-thods.Thirdly,the cloud model evaluation method was introduced,and the uncertainty of qualitative concepts was described and quantified by using three digital characteristics of expectation,entropy and super-entropy,and the results were displayed intuitively in the form of cloud images.Finally,the model was applied in an example and compared with the fuzzy comprehensive evaluation method.The case analysis shows that it is practical and feasible to evaluate the supervision of unit equipment main-tenance fees by using the proposed model,and the evaluation result is more accurate and intuitive than that of the fuzzy comprehensive evaluation method.
By analyzing the recorded operation data of a nuclear power plant (NPP), its results can serve the fault detection or operation experience feedback. Data missing exists in the recorded operation data. It may lower the data quality and affect the accuracy of the analysis results. In order to improve the data quality, two parts of researches are carried on. Firstly, to locate the missing data accurately the detecting algorithm for missing data of the NPP operation parameters based on wavelet analysis. Different judging basis is proposed for discrete and continuous missing respectively. Then, the filling method based on the hot deck algorithm are studied. As the dynamic properties of the parameters are closely related to the operating state of NPP, the similarity of the operation parameter vectors are formed to express the similarity of the operating states, so as to fulfill the requirements of the hot deck algorithm. To improve the accuracy of the measuring results, taken the differences between the characteristics of the analog parameters and the switch parameters into consideration, the similarity measurements using Mahalanobis distance for the analog parameter vectors and the matching measure for the switch parameter vectors are studied respectively. Finally, the operation data is taken to build the experiment data set for the algorithm verification. The results shows that the designed algorithm performs much better than the mean interpolation method and LSTM.
电磁弹射技术是一种高效可靠的加速驱动方式,将电磁弹射技术运用于车载无人机弹射上,具有机动灵活、通用性强等优点.首先,对车载无人机弹射的直线感应电机和端部效应进行了介绍;然后,根据无人机弹射加速指标要求,设计了一种用于车载无人机弹射用的双边直线感应电机;最后,使用有限元的方法进行了仿真,并对不同电流大小和频率下的加速过程进行了对比.仿真结果表明:该电机达到了无人机加速弹射指标要求.
针对传统有限元法建立的舰载机阻拦网动力学模型仿真效率较低问题,建立了一种舰载机阻拦网简化动力学模型.首先,基于集中质量法建立了柔性阻拦网的多体动力学模型,并对舰载机的几何外形进行合理简化,建立了舰载机和阻拦网间的接触碰撞模型;然后,联合阻拦网模型、舰载机模型以及阻拦装置模型,组成了完整的舰载机阻拦装置系统简化仿真模型;最后,将简化模型和商业有限元模型的仿真结果进行了对比分析.仿真结果揭示了阻拦网动态过程规律,验证了简化模型的有效性、准确性和高效性.
电磁轨道发射装置绝缘体在发射试验后易出现绝缘性能劣化而影响发射装置寿命.为研究不同劣化因素对绝缘性能的影响规律,将影响绝缘性能的因素解耦成6个独立状态,并对这6种典型的绝缘劣化形貌的形成和危害进行了讨论,设计了绝缘性能实验.不同试样的表面电阻率测量结果表明:积铝和液膜对绝缘劣化的影响最大,杂质和接缝处积铝其次,烧蚀碳化和膛内高温的影响最小;不同试样的直流沿面闪络电压高于交流沿面闪络电压,但二者变化趋势相似,均可以反映材料的绝缘性能;试样的耐受电压能力与其表面电阻率关系密切,积铝和液膜导通了试样表面,杂质和接缝处积铝试样的耐受电压能力较差,约为烧蚀碳化试样的1/2、加热试样的1/4.
