新“三资”推进兵团农业产业化

推进农业产业化经营,是在市场经济条件下,更加适应兵团生产力发展要求的经营方式和产业组织形式。而新“三资”则是实现农业产业化、增加农牧团场职工收入的重要途径之一。     

潜在故障状态可测的一种故障检查模型

从系统的功能故障状态和潜在故障状态两方面讨论了故障检查模型,基于延迟时间模型推导了系统的期望可用度模型并对其适用性进行了讨论与验证。     

Experimental and numerical investigations of interface properties of Ti6Al4V/CP-Ti/Copper composite plate prepared by explosive welding

Explosive welding technique is widely used in many industries. This technique is useful to weld different kinds of metal alloys that are not easily welded by any other welding methods. Interlayer plays an important role to improve the welding quality and control energy loss during the collision process. In this paper, the Ti6Al4V plate was welded with a copper plate in the presence of a commercially pure titanium interlayer. Microstructure details of welded composite plate were observed through optical and scanning electron microscope. Interlayer-base plate interface morphology showed a wavy structure with solid melted regions inside the vortices. Moreover, the energy dispersive spectroscopy analysis in the interlayer-base interface reveals that there are some identified regions of different kinds of chemical equilibrium phases of Cu–Ti, i.e. CuTi, Cu₂Ti, CuTi₂, Cu₄Ti, etc. To study the mechanical properties of composite plates, mechanical tests were conducted, including the tensile test, bending test, shear test and Vickers hardness test. Numerical simulation of explosive welding process was performed with coupled Smooth Particle Hydrodynamic method, Euler and Arbitrary Lagrangian-Eulerian method. The multi-physics process of explosive welding, including detonation, jetting and interface morphology, was observed with simulation. Moreover, simulated plastic strain, temperature and pressure profiles were analysed to understand the welding conditions. Simulated results show that the interlayer base plate interface was created due to the high plastic deformation and localized melting of the parent plates. At the collision point, both alloys behave like fluids, resulting in the formation of a wavy morphology with vortices, which is in good agreement with the experimental results.     

使用低分辨率雷达和神经网络进行舰船目标识别

本文研究使用低分辩率下靶区雷达包络线、预处理和神经网络工具进行舰船目标分类的方法。文中使用改进的傅里叶离散梅林变换来提取对雷达姿态角变化不太敏感的某些特征。使用Kohonen的学习矢量量化(LVQ)自组织映射对这些特征矢量进行分类。文中也研究了使用反向传播算法进行训练的前馈网络在目标分类中的应用,并将这一分类系统用于模拟和真实两种数据。对于目标姿态角误差不超过30度的真实数据,分类的正确率高达90％。     

Aerial multi-spectral AI-based detection system for unexploded ordnance

Unexploded ordnance(UXO) poses a threat to soldiers operating in mission areas, but current UXO detection systems do not necessarily provide the required safety and efficiency to protect soldiers from this hazard. Recent technological advancements in artificial intelligence(AI) and small unmanned aerial systems(sUAS) present an opportunity to explore a novel concept for UXO detection. The new UXO detection system proposed in this study takes advantage of employing an AI-trained multi-spectral(MS...     

Microwave absorption properties of carbonyl iron-based paint coatings for military applications

The paper explores the possibilities of using carbonyl iron in the form of a powder for the manufacture of radar-absorbing paints-reducing the radar signature of the objects that they cover. The attenuation values in the range of 4-18 GHz for various coating thicknesses, ranging from 0.5 to 2.00 mm with 0.5 mm increment, and for different absorber content-75% and 80%, as well as the use of two different binders in the form of epoxy resins with hardeners, were investigated. For the frequency of 1...     

The Pervasive Role of Rank in the Health of U.S. Veterans

The following article tests the hypothesis that veterans have better health if they were officers when they were in the U.S. military than if they served in the enlisted ranks. It examines this hypothesis by presenting results from logistic regressions that are based on four surveys: the National Survey of Veterans, the Survey of Retired Military, the Panel Study of Income Dynamics, and the Wisconsin Longitudinal Study. In all four of these surveys, the evidence is consistent with the hypothesis that military rank is associated with health, particularly among veterans who served longer. It also suggests that the health gradient by rank is independent of similar gradients by education and income as well as health differences by race. These findings indicate that health may be influenced not just by differences in civilian society but also by those in the military.