基于FPGA的CCD光积分时间大范围实时自调节系统

为了提高系统的自适应性、探测能力及测量精度,常常需要系统能根据待测光照强度自动实时大范围地调节电荷耦合器件(CCD)光积分时间.在分析了TCD1304AP型线阵CCD的特性、工作过程与驱动时序的基础上,设计了基于现场可编程逻辑门阵列(FPGA)控制的CCD光积分时间大范围实时自适应调节系统.研究分析了光积分时间计算算法,选用EP1C20F400C8作为硬件载体,使用Verilog语言对算法及CCD驱动时序进行了硬件描述;采用QuartusII软件对设计进行编译、综合,并用Modelsim进行了前后仿真;用自然光与LED光源对整个设计进行了实际测试.测试结果表明系统光积分时间调节范围在10μs～10 s以上,最小调节时间精度为0.25 μs,完全可以满足光积分时间的大范围实时自动无极调节.     

滚子摆动从动件盘状凸轮轮廓曲线的确定

滚子摆动从动件盘状凸轮机构在双活塞泵送机构中得以应用.本文通过对双活塞泵送机构工作原理及运动机理的分析,确定了其补偿凸轮机构--滚子摆动从动件盘状凸轮机构凸轮轮廓曲线,并加以应用,取得较好的效果.     

一种自驱动开合型双模式离合器

介绍一种基于海表面波浪运动的机械装置,详细说明其机械结构特点和工作原理,阐述如何利用其开合可变的特性带动测量平台不停的在海面以下做垂直方向的上下运动,从而实现了无人值守的情况下,进行全天候长期连续定点的测量海洋环境垂直剖面参数.此机械装置除具有结构简单性和制造成本低廉的特点外,更显著的优点为自身的升降运动和开合状态的变化全是靠海上无时不在的波浪能,无需电动部件的驱动,从而很好的解决海上自动监测系统的能源供应问题.     

Gauss curvature-driven image inpainting for image reconstruction

In this paper, we propose a third-order Gauss curvature-driven geometric diffusion Partial Differential Equation for inpainting and reconstructing images. In Gauss curvature-driven diffusion processes, the rate of diffusion is directly proportional to the Gauss curvature value of the level curve. Since the Gauss curvature is the product of principal curvatures, its value become zero when even one of the principal curvatures is zero. Therefore, when Gauss curvature is used as a driving function for diffusion, the evolution preserves some of the meaningful structures with nonzero mean curvature values (viz. curvy edges, corners, etc.). However, the noise features always have nonzero Gauss curvature value and hence the diffusion process effectively removes them. The inpainting property of geometric PDE based on the Gauss curvature is being used in this work for reconstructing lost or degraded information. A filter is proposed to reconstruct the original images from the observed blurred and noisy images along with inpainting the desired image domain.     

气动分置式斯特林制冷机的等温模型分析

涉及的气动分置式斯特林制冷机实验性能为40 W输入80 K/1 W,是上海技术物理研究所三期创新研究项目,本文采用等温模型对该制冷机的制冷性能进行理论计算,计算结果与实验值基本一致。另外,还对制冷机一些参数对理论制冷量、冷损、有效制冷量等的影响进行分析,为合理选取这些参数提供理论依据。     

Evolutionary design of user interfaces for workflow information systems

In this paper we argue that user interface design should evolve from iterative to evolutionary in order to support the user interface development life cycle in a more flexible way. Evolutionary design consists of taking any input that informs to the lifecycle at any level of abstraction and its propagation through inferior and superior levels (vertical engineering) as well as the same level (horizontal engineering). This lifecycle is particularly appropriate when requirements are incomplete, partially unknown or to be discovered progressively. We exemplify this lifecycle by a methodology for developing user interfaces of workflow information systems. The methodology involves several models (i.e., task, process, workflow, domain, context of use) and steps. The methodology applies model-driven engineering to derive concrete user interfaces from a workflow model imported into a workflow management system in order to run the workflow. Instead of completing each model step by step, any model element is either derived from early requirements or collected in the appropriate model before being propagated in the subsequent steps. When more requirements are elicited, any new element is added at the appropriate level, consolidated with the already existing elements, and propagated to the subsequent levels. A workflow editor has been developed to support the methodology.     

Mathematical Modeling of ESR Process for Hollow Ingot with Current Supplying Mould

With increasing demand for large cylindrical forgings,a new technology—electroslag remelting(ESR)for direct manufacture of hollow ingots rather than solid ingots has been developed.The main features of the process include a T-shaped current supplying mould(CSM),double power supply,an ingot withdrawing system,a metal level automatic control system based on a level sensor using the electromagnetic eddy current method,and the exchange of a consumable multi-electrode.ANSYS software was used to calculate the fluid flow and heat transfer in the slag bath and metal pool of this ESR hollow ingot process with its T-shaped CSM.The mathematical model was verified by measuring the geometry of the liquid metal pool as observed in the macrostructure of650mm(external diameter)/450mm(internal diameter)hollow ingots by sulphur print method:the observed shape and depth of the slag bath were consistent with the simulated results.Simulation of the ESR process can improve understanding of the process and allow better operating parameters to be selected.     

Preserving architectural pattern composition information through explicit merging operators

Composable software systems have been proved to support the adaptation to new requirements thanks to their flexibility. A typical method of composable software development is to select and combine a number of patterns that address the expected quality requirements. Therefore, pattern composition has become a crucial aspect during software design. One of the shortcomings of existing work about pattern composition is the vaporization of composition information which leads to the problem of traceability and reconstructability of patterns. In this paper we propose to give first-class status to pattern merging operators to facilitate the preservation of composition information. The approach is tool-supported and an empirical study has also been conducted to highlight its effectiveness. By applying the approach on the composition of a set of formalized architectural patterns, including their variants, we have shown that composed patterns have become traceable and reconstructable.     

分步制动技术的应用与分析

从制动技术多种复杂功能应用要求入手,分析了分步制动器(二级)的结构和工作原理。结合起重机大(小)车行走机构以及重型振动筛停车制动的应用实例,进一步讨论了分步制动器的具体应用。最后,提出了分步制动技术的发展前景和展望。