DCS与高压变频技术在电气设备中的节能分析

详细介绍了DCS系统与高压变频技术的概念与基本原理,通过介绍DCS系统与高压变频技术在电气设备控制与节能应用领域上各自的优势,提出了以DCS系统与高压变频技术相结合在电力设备中的应用方式,以改善电力系统的控制性能,达到集中管理、节约电能的目的。     

化工生产中DCS控制系统的应用

基于DCS控制系统的功能与结构及其特性,介绍了DCS系统在化工生产控制中的应用。针对工艺特点和控制要求,阐述了DCS控制方案的实施过程。运行结果表明,该系统具有良好的稳定性和实时性,对化工生产发展发挥了很大作用。     

DCS系统接地应用讨论

DCS系统由于其优秀的处理功能得到了各大企业的广泛应用。但是在DCS系统进行实际运行工作中,依旧因为各种因素的影响,会存在一定的问题,导致DCS系统的控制潜力不能稳定运行。本文介绍了DCS系统接地的基本要求和分类,论述了DCS系统接地原则和方法和注意事项。     

循环流化床锅炉DCS控制方案

介绍了循环流化床锅炉控制系统在DCS控制系统中的组态应用。对循环流化床主要的自动控制系统进行了分析,给出了DCS控制系统的配置方案,并对其实现的主要功能进行了介绍。     

核电厂DCS系统调试装置研制

核电厂DCS系统调试装置可与核电厂真实DCS机柜连接,形成控制闭环,使核电厂DCS系统的工程调试更便捷、有效。介绍了调试装置的原理、组成、软硬件结构,并以百万千瓦级核电厂DCS系统工程调试为例,描述了核电厂DCS系统调试装置的开发、工程调试和应用效果。     

和利时DCS系统在高炉煤气及转炉余热综合利用发电工程中的应用

以和利时(HOLLiAS-MACS)FM系列大型DCS系统在高炉煤气燃烧发电的设计应用为出发点,描述了高炉煤气燃烧发电DCS控制系统配置选型以及核心控制对象的控制实现方法。结合国内某钢厂20 MW全燃高炉煤气发电项目的应用实例,对该类型发电工程项目的 DCS系统选型、控制对象的控制思路、实现方法做了功能性介绍。     

用DCS控制6000m~3/h制氧机运行的探讨

介绍了 60 0 0 m3/h制氧机系统空压机控制装置进入 DCS并通过 DCS实现与空分控制装置的联网技术、自控制设备的选定及其安装注意事项。     

一种DCS组态系统及其应用

介绍了SUPCON JX-300DCS系统的特点及系统的组态，给出了系统在尿素生产过程中的应用，包括水溶液全循环尿素工艺，DCS控制方案设计。     

流浆箱液位分程控制技术的研究与应用

论文介绍了纸机中流浆箱液位控制的重要性及分程控制原理,采用DCS系统实现分程控制的优势,以及DCS系统的常用模块。并结合本单位实际应用情况,重点介绍了分程控制的编程思路、编程逻辑、程序处理流程。最后对实现分程控制时常见的问题给出了处理建议。     

集散控制系统及其在尿素生产过程中的应用

介绍了SUPCON JX－300DCS 系统的特点及系统的组态，给出了系统在尿素生产过程中的应用，包括水溶液全循环尿素工艺，DCS控制方案设计。     

Semiautomated methods for cancellous bone histomorphometry using a general-purpose video image analysis system

Semiautomated methods are used to measure elongated, curved and complex branching profiles and isolated perimeter segments in monochrome video images with a general-purpose analysis system. These methods are used to make the major primary measurements of bone histomorphometry. Accuracy and reproducibility of the image acquisition, processing and measurement system is documented by measuring a semicircular standard of known dimensions. Semiautomated applications of the Ar/Le method for measuring areas and perimeters, and calculating lengths and widths of osteoid seams, lengths of mineralization labels and mineral apposition rate, wall width, indirect measurements of eroded, osteoclastic and osteoblastic perimeters without tracing, and measurement of mineralized or total cancellous bone area and perimeter gave values comparable to measurements of the same parameters by tracing or grid counting techniques with equal or better reproducibility and much greater efficiency. Intraindividual variation in measuring multiple bone biopsies was comparable to that reported with current standard methods. Major sources of variability for semiautomated methods were image magnification and selection of profile edges by thresholding, and sources of variability for manual methods are image magnification, numbers of orthogonal intercepts, tracing speed and accuracy of the algorithm used to measure traced pixels. Semiautomated methods are accurate, reproducible and rapid methods suitable for bone histomorphometry.     

BODY PRESSURE DISTRIBUTION OF AUTOMOBILE DRIVING HUMAN MACHINE CONTACT INTERFACE

Aiming at the fatigue and comfort issues of human-machine contact interface in automo- bile driving and based on physiological and anatomical principle,the physiological and biochemical process of muscles and nerves in the formation and development of fatigue is analyzed systematically. The fatigue-causing physiological characteristic indexes are mapped to biomechanical indexes like muscle stress-strain,the compression deformation of blood vessels and nerves etc.from the perspec- tive of formation mechanism.The geometrical model of skeleton and parenchyma is established by applying CT-scanned body data and MRI images.The general rule of comfort body pressm'e distribu- tion is acquired through the analysis of anatomical structure of buttocks and femoral region.The comprehensive test platform for sitting comfort of 3D adjustable contact interface is constructed.The test of body pressure distribution of human-machine contact interface and its comparison with subjec- tire evaluation indicates that the biomechanical indexes of automobile driving human-machine con- tact interface and body pressure distribution rule studied can effectively evaluate the fatigue and comfort issues of human-machine contact interface and provide theoretical basis for the optimal de- sign of human-machine contact interface.     

DESIGN AND ANALYSIS OF NOVEL ACTIVE ACTUATOR TO CONTROL LOW FREQUENCY VIBRATIONS OF SHAFT SYSTEM

Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.     

Histochemical and ultrahistochemical localization of heavy metals in calf organs

Cadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium.     

MODELING METHOD FOR PRODUCT STRUCTURE MAPPING BASED ON REVERSE SOLVING OF LOCUS AND MOTION

Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.     

Mass spectrometry analysis of the influenza virus

The role of mass spectrometry to probe characteristics of the influenza virus, and vaccine and antiviral drugs that target the virus, are reviewed. Genetic and proteomic approaches have been applied which incorporate high resolution mass spectrometry and mass mapping to genotype the virus and establish its evolution in terms of the primary structure of the surface protein antigens. A mass spectrometric immunoassay has been developed and applied to assess the structure and antigenicity of the virus in terms of the hemagglutinin antigen. The quantitation of the hemagglutinin antigen in vaccine preparations has also been conducted that is of importance to their efficacy. Finally, the characterization and quantitation of antiviral drugs against the virus, and their metabolites, have been monitored in blood, serum, and urine. The combined approaches demonstrate the strengths of modern mass spectrometric methods for the characterization of this killer virus. [This article was published online 10 September 2008. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 7 November 2008.]     

气化炉三维扫描测量与数据处理

以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.     

基于AMESim和MATLAB联合仿真的双变量电动静液作动器性能分析

介绍了双变量电动静液作动器(EHA, Electro hydrostatic Actuator)系统的结构组成与工作原理,分别基于AMESim和MATLAB软件,建立了其机械、液压部分的模型和电机、控制部分的模型,并采用接口技术将二者结合,建立了其完整的非线性数学模型。采用分配解耦控制策略以及AMESim和MATLAB联合仿真技术对其进行阶跃和正弦响应性能仿真分析。仿真结果表明：所设计的双变量EHA系统原理正确,满足性能要求。分配解耦控制策略可以很好地解决双变量EHA系统的相乘非线性问题,保证了系统的刚度和鲁棒性。     

45钢电子束扫描相变硬化组织和硬度的研究

电子束表面处理可以提高钢铁材料的表面硬度和力学性能。研究电子束扫描对45钢硬化层组织和性能的影响,探讨电子束功率、扫描速度等工艺参数对硬化层组织和性能的影响。采用扫描电镜分析45钢电子束表面强化层的显微组织,用显微硬度计进行硬度测试。结果表明,45钢经电子束扫描处理后,硬化层的组织为针状和板条状马氏体,组织比常规调质处理更加均匀、细小,试样表面的平均硬度达58 HRC,比淬火加低温回火处理的硬度高3～5 HRC,是调质处理的两倍,从处理表面往下沿深度方向硬度逐渐减小。电子束工艺参数对硬化层组织和性能有较大影响,硬化层宽度和深度随着电子束功率的增加而增加,随着扫描速度的增加而减小;硬化层的最高硬度随着电子束功率密度的增加而增加,随着扫描速度的增加而减小。     

Imaging applications of synchrotron X-ray phase-contrast microtomography in biological morphology and biomaterials science. I. General aspects of the technique and its advantages in the analysis of millimetre-sized arthropod structure

Synchrotron‐generated X‐rays provide scientists with a multitude of investigative techniques well suited for the analysis of the composition and structure of all types of materials and specimens. Here, we describe the properties of synchrotron‐generated X‐rays and the advantages that they provide for qualitative morphological research of millimetre‐sized biological organisms and biomaterials. Case studies of the anatomy of insect heads, of whole microarthropods and of the three‐dimensional reconstruction of the cuticular tendons of jumping beetles, all performed at the beamline ID19 of the European Synchrotron Radiation Facility (ESRF), are presented to illustrate the techniques of phase‐contrast tomography available for anatomical and structural investigations. Various sample preparation techniques are described and compared and experimental settings that we have found to be particularly successful are given. On comparing the strengths and weaknesses of the technique with traditional histological thin sectioning, we conclude that synchrotron radiation microtomography has a great potential in biological microanatomy.