鲜食玉米加工工艺及自动化设备设计

目的：解决鲜食玉米切割时准确率较低，随机误差较大，容易损伤籽粒问题。方法：设计了一种新型工艺的甜糯玉米加工生产线，该生产线利用机器视觉技术对玉米姿态进行判断，通过换向设备完成玉米姿态调整，设计适应性定位机构分别对玉米头尾进行切割，再依据切割后果穗苞叶附着力差异特点进行留层加工，经相机品质筛选后装箱，并利用样机进行加工试验。结果：该生产线加工效率达1 500穗/h；留层合格率为90.2％；籽粒破损率为1.81％。结论：该鲜食玉米加工生产线实现了玉米的上料、排序、切割、剥皮等工序自动化，实现苞叶合理留层，对比传统设备更加保护玉米籽粒。     

An Analytical Queueing Network Model for Flexible Manufacturing Systems with a Discrete Handling Device and Transfer Blockings

In this paper, we study job shop-like flexible manufacturing systems (FMSs) with a discrete material handling system (MHS). In such FMSs, the MHS is a critical device, the unavailability of which may induce transfer blockings of the machines. The FMS devices therefore are hierarchically structured into primary and secondary devices to manage such blocking and avoid deadlocks in these FMSs.For evaluating the quantitative steady-state performance of such FMSs, we propose an analytical queueing network model that relies on an approximate method proposed for analyzing computer systems with simultaneous possessions of resources. Such a model is obtained using the concept of passive resources and by aggregating the FMS workload data so that models are much more tractable.The analytical results are validated against discrete event simulation and shown to be very encouraging. We also show how to increase their robustness, especially under light workload conditions, by modifying an assumption of the method concerning service time distributions.     

Petri网理论在柔性制造系统（FMS）性能分析中的应用

本文用 Petri 网的一个子类——时间事件图对流水车间型和作业车间型的柔性制造系统(FMS)建模并进行理论分析,给出了可行排序的判定条件及系统中托盘数量配置与系统生产率的关系,对系统的主要性能指标,如生产周期、工件驻留时间、在制品库存等给出了定量描述.这些结果为系统的设计和运行提供了理论依据.     

Study of microstructure, phases and microhardness of metallic coatings deposited by flame thermal spray

The recharging technique by thermal spraying offers the opportunity of renovating the worn surface parts of a machine element to give it again a new technical life despite its previous degradation in service. This process has consequently interesting economic impacts. In order to improve the adherence between 100Cr6 steel deposits and the substrate material (left worn crankshafts), company SNC ATRA of Béjaïa uses at present a composite formed by (100Cr6 steel/molybdenum bond coat of 0.2 mm thick/crankshaft substrate). As a matter of fact, it is shown in the present work that the molybdenum bond coat is not appropriate since, for the 0.2 mm thickness, lateral cracks are observed in the middle of the bond coat. On the other hand, our experiment is that a deposit of 100Cr6 steel projected directly on the substrate seems more promising since no gaps or cracks were detected at the “deposit/substrate” interface of this two-material composite. Lastly, phase analysis using X-ray diffraction confirmed that during spraying process, a stable -phase (bcc) of 100Cr6 wire was transformed to a new phase of γ-phase (fcc). The coatings exhibited the higher microhardness which would contribute to increase wear resistance.     

Bicharacteristic quality control in manufacturing

In this paper, the importance of bicharacteristic quality control has been discussed, when it is desired to exercise process control on manufacturing products that present two measurable characteristics which can suffer variations and on the other hand are considered significant for the functioning or the acceptance of the product. The verification that the process is in control or not is made by examining periodically the items of the samples drawn and plotting the points representing the mean of the characteristic in analysis on the corresponding charts. Using the computational program developed, a practical application is carried out for a mechanical manufacturing component that presents two critical characteristics. Also, a programmable mathematical model has been developed, aiming to computationally determine the sample size, and the interval between successive samples, which minimize the expected total cost. Idealized numerical application illustrates the use of the cost model that optimizes these parameters.     

关于加工生产线的一种新的模型及其扰动分析

本文首先建立在实际生产中应用较广的串联生产线和装配生产线的新的代数摸型(在新 韵代数系下).基于这类模型,在扰动幅度大小没有任何限制的情况下,对平均服务时间的扰 动,建立扰动传播的数学方程,给出系统输出率对平均服务时间的灵敏度公式.仿真结果验证 了理论分析结果,其精度令人满意.     

拜耳法氧化铝制造成本的分析与降低途径

通过对拜耳法氧化铝制造成本的构成分析，提出了降低制造成本的途径，以期对增强企业竞争力、提高经济效益有所帮助。     

Learning-based algorithms in scheduling

The aim of the paper is to present a conception of intelligent learning-based algorithms for scheduling. A general knowledge based model of a vast class of discrete deterministic processes is given. The model is a basis for the method of the synthesis of intelligent, learning-based algorithms, that is described in the paper. The designing simulation experiments that use learning is also described. To illustrate the presented ideas, the scheduling algorithm for a special NP-hard problem is given. The significant feature of the problem is that the retooling time depends not only on a pair of jobs to be processed directly one after the other, but also on the subset of jobs already performed. The proof of the NP-hardness of the problem is also given in the paper.     

专用测量仪微机检测系统的设计

专用测量仪是为自动测量汽车差速器壳的多个参数而设计的，其控制系统由硬件和软件两个部分组成。硬件以微机为核心，配以各种外设和接口电路；软件设计成ＷＩＮＤＯＷＳ应用程序，用面向对象的Ｃ＋＋语言编制，具有良好的人机交互图形界面。采取硬、软件双重抗干扰措施，大大地提高了测量仪的测量精度。     

镁合金产品生产过程绿色制造技术的研究

绿色制造是现代制造业可持续发展的必由之路,镁合金作为最轻的结构材料其应用将越来越广。本文将绿色制 造理论同镁合金产品的生产相结合,并根据绿色制造要求提出了改进方案。