中子测水仪—微机配料称量控制系统在铁合金电炉上的应用

前言铁合金电炉是耗能很大的设备,铁合金生产是一个很复杂的高温物理化学过程,原料的称量控制,又是铁合金电炉生产中的关键问题,它直接影响着炉子的正常运行和技术经济指标。目前国内基本上是采用电子秤和单元仪表组合的称量系统,由于没有称量的补偿功     

分侧控制蓄热式加热炉控制系统设计

四段两单元分侧控制蓄热式加热炉采用CS1000集散控制系统，系统网络包括现场控制层和中央监控层，CPU、电源及通讯单元采用双重化冗余技术，主从CPU之间可无扰切换。针对被控对象大滞后、非线性等特性，采用了模糊PID、自适应等一些高级的控制算法和策略，完成加热全过程的数据采集、过程控制、逻辑控制、快速连锁等功能，系统运行稳定可靠，完全满足工艺要求。     

同步电机中压变频软启系统在电动鼓风机中的应用

包钢7#、8#、9#电动鼓风机采用西门子同步电动机变频软启系统,该系统核心由SIMOVERT S6SB20系列的中压变频器、SIMOTRAS_HD励磁控制器及保护装置等组成。SIMADYN D作为该套中压变频器控制中心负责控制各励磁单元、灭磁单元及变频控制单元的协调工作。控制系统采用PROFIBUS_DP的通讯方式,运行稳定、可靠。     

PLC在有色金属矿井通风机控制系统中的应用

采用PLC可编程逻辑控制集成元件进行有色金属矿井通风机控制系统的优化设计,提高矿井通风机控制的可靠性。系统的模块化设计主要包括控制信号采集模块、主控单元模块、信号A/D转换模块、串联谐振匹配符模块和控制中断及复位模块等。采用PLC作为主控芯片实现系统的硬件电路设计和控制算法程序加载。仿真结果表明,该系统可靠稳定,功能完善。     

脉冲燃烧控制在大型高温热处理炉上的应用

针对合金板带产品在热处理加热过程中对燃烧气氛稳定性、炉温均匀性和控温精度、加热质量等指标要求较高的特性,深入研究脉冲燃烧控制技术,介绍了脉冲燃烧控制的技术特点及系统组成,探讨了特钢大型高温热处理炉上使用的脉冲燃烧控制模型的原理及特性。该炉采用的脉冲燃烧控制技术具有系统安全可靠、运行稳定、控制灵活、精度高的特点,保证了钢板热处理的高质量和稳定性。     

可吸附性还原物质对锌电积的影响及对策研究

湿法炼锌电积单元是一个复杂的控制过程系统,本文研究了COD在系统中的行为.通过采用活性物质进行物理吸附和在线监测,稳定控制该物质的水溶液平衡量.实践表明,该方法能带来可观的经济效益.     

棒材连轧粗轧微张力控制

本文以PLC为核心控制单元,对棒材粗轧机组进行微张力控制。PLC对各电机的控制采用PI控制规律,有效地利用了PLC的系统资源。通过实际验证,该系统运行稳定,各项指标均满足生产要求。     

铝冷轧机恒张力控制系统改造

在铝冷轧机恒张力控制系统的改造中 ,采用了超声波测距仪测量卷径的方法代替原模拟计算方法 ,保留原张力控制单元 ,从而有效控制了张力的稳定性 ,并节约了改造费用。改造系统自投入运行以来 ,系统工作稳定 ,可靠性高。     

棒材连轧粗轧微张力控制

本文以PLC为核心控制单元,对棒材粗轧机组进行微张力控制.PLC对各电机的控制采用PI控制规律,有效地利用了PLC的系统资源.通过实际验证,该系统运行稳定,各项指标均满足生产要求.     

铬铁生产自动控制系统的优化

采用优化烧结配料和造球控制流程;优化矿热炉本体功率控制系统;优化预热窑的控制中炉料分配下料系统和加强混合室温度串级控制的稳定、平衡控制等相关技术对生产过程进行研究,完善并优化铬铁生产自动化系统,使生产达到最佳,解决了生产过程中的难题。     

High-resolution digital retroillumination imaging of the posterior -004 capsule after cataract surgery

PURPOSE: To develop a system for high-resolution imaging of the posterior lens capsule after intraocular lens surgery for objective assessment of posterior capsule opacification (PCO). SETTING: Department of Cataract and Refractive Surgery, St. Thomas' Hospital, London, United Kingdom. METHODS: A system was developed that uses coaxial illumination and imaging based on Zeiss components with a digital camera directly linked to a computer for online image verification and image analysis. RESULTS: The system produced high-resolution digital images with even background illumination of sufficient quality to demonstrate progressive lens epithelial cell changes that are amenable to computer image analysis. CONCLUSION: This system produced excellent images for objective documentation and quantitative measurement of PCO.     

Aberrations of spherocylindrical spectacle lenses

A procedure has been developed for tracing a bundle of rays through and ophthalmic lens and a schematic eye with its primary line of sight pointed through various parts of the lens. A bundle of eight rays can provide data for assessing the quality of the image formed by such a system. To test the procedure and to generate data which can help in selecting a method for evaluating image quality, we selected a single lens as an example. The lens selected has a spherical back surface (-5.00 diopters) and a toric front surface (+15.00 diopters in the vertical and /10.00 diopters in the horizontal). It has a center thickness of 5 mm and glass of index 1.523. Spot diagrams were generated with the eye pointed in various directions through the ophthalmic lens. The data generated showed that peripheral bundles which fall between the principal meridians emerge as astigmatic bundles. This leads to the proposal that blur circle theory can be used for evaluating the quality of the optical image and that it suffices in the case of a spherocylindrical ophthalmic lens to base the tolerances for refractive power on measurements made in the principal meridians.     

视频图像比色方法在钢厂加热炉钢坯温度测量系统中的应用

在冶金行业的加热炉生产工艺中,为监控加热炉内部燃烧状况,提高燃烧质量,采用数字图像采集与图像处理方法,实现大范围目标温度全面实时测量的高温测温电视系统,为加热炉的自动控制提供了可靠依据.     

Choosing the right clinical camera. Part II

From a practical standpoint, both ring and dual flash are easier to control for the operator. It is not necessary to remember to put the flash on the side of the mirror or to rotate the flash to avoid unwanted shadows. The point source flash requires a learning curve and the dual point source flash, away from the lens, has limited applications. The lighting quality brings out the third dimension in photography and is therefore among the most important factors when taking image quality into consideration. The dual source flash on the lens system provides a more pleasing and natural illumination than the other systems. The Nikon SB21-B fulfills these requirements while offering the possibility to be used as a single source flash unit. Furthermore, the flash unit's close proximity to the lens allows the light to reach virtually any area in the mouth. Lastly, the TTL option takes care of the concern regarding the consistency of the light intensity and significantly speeds up the recycling time.     

Diffractive bifocal lens designs

Modifying the number, width, depth, and shape of the echelettes in a diffractive bifocal lens will influence the image intensity and quality within the zero, first, and higher order images. By appropriately varying these parameters optimal bifocal lens designs may be achieved.     

Measurement of ocular position using Purkinje images. Part 1. A new measurement system

I developed a new system of measuring ocular position using the first and fourth Purkinje images. This method used two images which were reflected from the front surface of the cornea and the back surface of the lens. I got a cross line from the first Purkinje image by putting a cross lens filter in front of the infrared camera. When I superimposed the vertical line upon the fourth image, I could get the optic axis of the eye. In order to measure the ocular position, I measured the angle of the optic axis. The accuracy of this system was +/- 0.1 degrees and the maximum error was smaller than +/- 0.5 degrees. Measurements with this system were easily obtained from squint patients and correlated well with results from the prism cover test (R2: 0.941). This measurement system was more useful than the prism cover test because I was able to measure horizontal deviations more precisely.     

一种高温高压下粘结物料分离松动装置的设计

介绍一种适用于高温高压环境下防止粘结矿料的松动装置。通过设置交错布置松动齿,有效地将粘结成块状的物料进行分离松动;通过在密封系统内采用冷却水、填料密封、高压气体密封共同作用,保证了本装置在高温高压下使用的可靠性。     

Isolation and characterization of a myotoxic phospholipase A2 from the venom of the arboreal snake Bothriechis (Bothrops) schlegelii from Costa Rica

PURPOSE: To evaluate the cytotoxicity of immunotoxin 4197X-ricin A (4197X-RA) and its ability to inhibit protein synthesis and human lens epithelial cell (LEC) proliferation on the inner surface of the lens capsule. SETTING: Houston Biotechnology, Inc., The Woodlands, Texas. METHODS: A cell culture system was established using human LECs as a model for the proliferation of remnant LECs that occurs during posterior capsule opacification (PCO) after extracapsular cataract extraction. The LEC culture system was also used in vitro for testing compounds that might inhibit this process in vivo. Human LECs were cultured on the surface of the original lens capsule fixed to collagen. Variability was reduced by dissecting each lens capsule into equivalent halves and exposing the segments to immunotoxin 4197X-RA. RESULTS: Protein synthesis and LEC proliferation were almost completely inhibited at relatively low 4197X-RA concentrations after short exposure. The inhibitory effects persisted up to 3 weeks after withdrawal of the immunotoxin and after several media exchanges. CONCLUSION: Immunotoxin 4197X-RA may help prevent PCO after primary cataract surgery.     

Design of an emergency teleradiology system based on progressive transmission

In clinical surgery, there are frequent needs for communication between the house staff and the attending physician in an emergency situation. To overcome the limitation of voice communication through the telephone line, we have designed an 'emergency teleradiology system' which can be used for emergency surgical and medical decision making. This system can transmit the high quality images of CT, MRI, and other X-ray data using a PC attached to a modem through the conventional telephone line. It is based on the progressive transmission system which enables the successive update of a received image. The iterative residual coding/decoding algorithm efficiently compresses the image to maximally utilize the low bandwidth PSTN channels. This system also satisfies design requirements such as low-cost, ease of operation, fast transmission, and interactive image communication including voice. Test results using several CT, MR, and X-ray images evaluate the compression performance, image quality, transmission time and computational time of the coding and decoding processes, thus demonstrate the usefulness of this system in an emergency situation.     

基于机器视觉的风口回旋区温度检测算法

 应用机器视觉理论，引用微元积分思想建立了辐射图像信息与高炉风口回旋区二维温度场梯度分布的关系模型，并针对CCD非接触测量回旋区温度过程中因温度过高易出现CCD输出过饱和电流问题，提出了大于CCD噪声总量和防止饱和电流输出的快门时间控制模型。通过小型煤气燃烧实验和高炉风口现场实验表明：该温度检测算法正确，快门控制模型能有效地防止图像出现“白炽”现象，提高了温度测量峰值。