天铁热力风机升级改造方案设计

通过对天铁集团高炉现状、风机现状的分析,提出了对热力厂风机升级改造的规划,确定了实施方案.该方案实施后将彻底改变风机渐进式改造的现象,使新高炉的备用机组发挥更大的作用,可增加现有高炉的风压、风量,使现有高炉的产量、冶炼强度进一步提高.     

我国民事诉讼中的司法鉴定制度之立法缺陷及其完善

由于立法的简略,致使司法鉴定在民事诉讼的实际操作中存在许多问题.拟在对我国民事诉讼中司法鉴定制度存在的立法缺陷和司法鉴定在司法实践中存在的诸多问题进行分析的基础上,提出完善我国民事诉讼司法鉴定制度的相关设想.     

冶炼平车移动DP总线编码器的应用

介绍了在铁合金电炉控制系统的改造中应用移动DP从站的实践,对铁合金电炉控制领域的开发及维护具有一定的借鉴作用.     

干熄焦生产操作方法的分析及优化

结合干熄焦的实际生产操作,对干熄焦工艺中焦炭物流、气体循环及锅炉系统中一些容易忽视的问题进行探讨,对一些不规范的操作方法的危害性进行分析,并提出改进的措施.     

包覆焊接铜包铝线铜带成形研究

铜包铝线已广泛应用于同轴电缆,但目前对铜包铝的研究主要集中在铜包铝设备的使用和机理上,而忽略了铜带的成形对其质量的影响.本文在介绍了包覆焊接法生产铜包铝线的优点和它的工艺流程的同时,分析了在铜包铝线的包覆焊接前铜带的成形的影响因素.     

强化知识管理提高企业的应变与创新能力

处于相同行业结构和机会的企业存在着很大差别.知识管理作为作管理创新的一种成果,面对知识时代更加激烈的市场竞争和经营环境的更为不确定性,知识管理在结合企业的具体发展情况下,将为企业的发展注入新的活力.     

职业教育发展的政府失灵与市场调节

职业教育的发展,主要是在市场和政府的相互调节下运行的.但完全的政府调节不利于职业教育的健康发展,完全政府调节下的职业教育会出现政府失灵现象,因而,市场的无形调节是非常重要的.市场调节主要包括人才需求、利益导向、人事制度等方面的调节.     

浅谈我国有色金属行业的技术创新发展与对策研究

在分析我国有色金属行业现状的基础上,指出随着国际贸易的不断加深,我国有色金属发展中的技术落后、设备陈旧等问题日益突出,使整个行业的发展受到严重制约.提出技术创新是促进我国有色金属行业持续发展的关键,并对现有问题的根源及解决办法进行了初步探讨.     

滚动卫板在冷轧带钢生产中的使用

随着现代冷轧带钢轧机线速度的加快,传统的球墨铸铁卫板不能适应冷轧机的需要,设计的滚动卫板解决了传统卫板的缺陷.通过生产实践的检验,产品质量有所提高,成本大幅降低,效益明显增加,同时减轻操作工劳动强度,设备利用率大大提高.     

考虑辐射影响的隔热纤维体的热导率分形模

根据纤维体内部分形结构特点,建立了计及温度影响的隔热纤维体的热导率分形模型.通过对硅酸铝纤维SEM图像的处理,得到了不同密度下硅酸铝纤维的孔隙面积和孔隙通道曲线的分形维数,并据此计算了硅酸铝纤维的热导率.实验结果验证了本文分形热导率模型的正确性.     

2004年铁合金市场回顾与2005年展望

2004年国际和国内铁合金价格波动较大，全年价格总体水平较往年有较大增长。2004年我国铁合金行业产销两旺，全年产量和出口量均创历史新高，市场价格较往年也有明显改善。但是，铁合金行业发展过热已引起国家有关部门和业界的高度重视，并相继出台了一系列相关的产业政策和调控、指导性措施，对整个铁合金行业的发展产生了深远影响。文章从生产、消费及进出口等方面对2004年中国铁合金市场进行了分析并对2005年市场前景进行了预测。     

Evaporation Research: Review and Interpretation

Literature regarding evaporation from soil, wet plant surfaces, and sprinkler droplets was examined, normalized, and interpreted. Much of the evaporation literature is difficult to compare and interpret; this paper offers comparisons and discussions of various findings by others as well as by the writers. Techniques of measuring and estimating evaporation from irrigation and rainfall are discussed. The partitioning between increased evaporation and decreased transpiration from a variety of research is quantified. Factors that impact the various forms of evaporation are listed and quantified. This review and summary will provide practitioners and researchers with theoretical and practical guidance on measurement techniques and estimates of evaporation under a wide range of conditions.     

Integrated Two-Dimensional Surface and Three-Dimensional Subsurface Contaminant Transport Model Considering Soil Erosion and Sorption

To investigate the complex hydrological, morphodynamic, and environmental processes in watersheds, a physically-based integrated two-dimensional (2D) surface and three-dimensional (3D) subsurface model for flow, soil erosion and transport, and contaminant transport in the surface-subsurface system is presented in this paper. The model simulates the rainfall-induced surface flow by solving the depth-averaged 2D diffusion wave equation and the variably-saturated subsurface flow by solving the 3D mixed-form Richards equation. The surface and subsurface flow equations are coupled using the continuity conditions of pressure and exchange flux at the ground surface. The model uses the concept of nonequilibrium in the depth-averaged 2D simulation of nonuniform total-load sediment transport in upland fields, considering detachments by rainsplash and hydraulic erosion driven by surface flow. The integrated 2D surface and 3D subsurface contaminant transport model takes into account the contaminant changes due to sediment sorption and desorption, as well as exchanges between surface and subsurface domains due to infiltration, diffusion, and bed change. The model applies the same set of surface equations of flow, sediment, and contaminant transport for describing both upland areas and streams, so that no special treatments are required at their interface. The established model has been evaluated by comparisons with published experimental, numerical, and analytical data and then applied in an agricultural watershed. The model is suitable for wetland areas and agricultural watersheds in which streams are not very narrow and deep, and meanwhile a relatively fine mesh that can distinguish the streams is preferred.     

Dynamic Modeling of Hydraulic Shovel Excavators for Geomaterials

The hydraulic shovel excavator has found significant applications in surface mining, construction, and geotechnical operations due to its flexibility and mobility. The key to high availability and utilization of this shovel is adequate understanding of machine dynamics and machine-formation interactions among other technical, operating, safety, and economic factors. These shovels are capital intensive, complex in design and operation within severely constrained environments. Detailed dynamic modeling and analysis are required to understand their effective utilization for achieving efficient operating performance and economic useful lives. Previous attempts at solving these problems are limited because they do not provide knowledge on the resistive forces and moments for efficient excavation. In this paper, the Newton-Euler techniques are used to develop hydraulic shovel dynamic models with numerical examples. Detailed analysis of the results shows that: (1) the kinematics of the stick-bucket joint (joint 3) is the most critical and effective control of this joint and is important input into efficient excavation design and execution; and (2) the highest resistive moments occur between the duration of 1.5 and 2.0?s after the start of formation excavation and the highest magnitudes are 1,500?Nm (for stick), 900?Nm (for bucket), and 600?Nm (for boom). Based on these results, the path trajectories, dynamic velocity and acceleration profiles, and dimensioned parameters for optimum feed force, torques, and momentum of shovel boom-bucket assembly can be modeled and used for efficient excavation. The optimum digging forces and resistances for the hydraulic shovel excavator can also be modeled and used to predict optimum excavation performance.     

天铁科技成果管理工作实践

论述了科技成果管理的内容和意义,结合企业实际介绍了天铁科技管理的制度、体系及实施效果。通过科技创新体系和成果管理制度建设,“十一五”期间促进了科技成果的开发和转化,有多个项目分别列人天津市技术创新重点为项目、天津市二十项重点项目,推动了企业持续快速发展。     

Probabilistic Capacity Models for Corroding Posttensioning Strands Calibrated Using Laboratory Results

The presence of air voids, moisture, and chlorides inside tendons or ducts was cited as a reason for the early age strand corrosion and failure in the Mid-bay, Sunshine Skyway, and Niles Channel posttensioned (PT) bridges in Florida, United States. Although rare, these incidents call for frequent inspection and structural reliability assessment of PT bridges exposed to moisture and chlorides. This paper develops and presents probabilistic strand capacity models that are needed to assess the structural reliability of such PT bridges and recommends a time frequency of inspection. A total of 384 strand test specimens were exposed to various void, moisture, and chloride concentration conditions for 12 and 21 months; the remaining tension capacities were then determined. Using this experimental data and a Bayesian approach, six probabilistic capacity models were developed based on the void type. The mean absolute percentage errors of these models are less than 4%, indicating that reasonably accurate prediction of the strand capacity is possible, when void, aggressive moisture, and chloride conditions are present.     

钛渣酸解过程中物相变化特征探讨

明确物相变化是剖析钛渣酸解机理和改进酸解工艺的关键点之一。综合应用化学分析、X射线衍射(XRD)分析、矿物解离分析以及扫描电镜形貌分析对某74钛渣酸解过程中主要物相的含量、形貌变化以及Ti、Si两种元素的含量及赋存变化进行了研究。结果表明:钛渣主要由黑钛石和辉石组成,酸解过程中黑钛石含量逐渐减小,辉石含量逐渐增加;反应过程中,酸主要以扩散的形式渗透到黑钛石颗粒表面及内部孔缝,从而分解黑钛石;酸解前后,辉石形貌无明显变化,但随反应深入,其解离度逐步提高;钛渣中Ti元素主要赋存于黑钛石中,Si元素主要赋存于辉石中,部分赋存于黑钛石和黑钛石-辉石混合物中,反应过程中Ti元素主要由黑钛石向TiOSO₄迁移,部分迁移至黑钛石-辉石混合物中;Si元素迁移并主要富集于辉石以及黑钛石-辉石混合物中。     

天铁物料结算系统的开发设计

天铁为了解决物料结算由于手工操作出现的差错率高、控制成本困难等问题,开发设计了计算机物料结算系统。从系统的安全性、网络和硬件的实现等方面,介绍了该系统的主要功能和特点及运行情况。系统运行情况证明,该系统的开发实现了数据共享和集中存储,完善了采购和销售的各环节,程序运行稳定,提高了工作效率。     

Behind closed doors: In-home workers' experience of sexual harassment and workplace violence.

The authors developed and tested a structural model predicting personal and organizational consequences of workplace violence and sexual harassment for health care professionals who work inside their client's home. The model suggests that workplace violence and sexual harassment predict fear of their recurrence in the workplace, which in turn predicts negative mood (anxiety and anger) and perceptions of injustice. In turn, fear, negative mood, and perceived injustice predict lower affective commitment and enhanced withdrawal intentions, poor interpersonal job performance, greater neglect, and cognitive difficulties. The results supported the model and showed that the associations of workplace violence and sexual harassment with organizational and personal outcomes are indirect, mediated by fear and negative mood. Conceptual implications for understanding sexual harassment and workplace violence, and future research directions, are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Design Error Classification, Causation, and Prevention in Construction Engineering

Construction and engineering practitioners have found it increasingly difficult to learn from their mistakes, particularly with regard to the prevention, identification and/or containment of design errors. Yet, design errors have been the root cause of numerous catastrophic accidents that have resulted in the death and injury of workers and members of the public. This paper examines and classifies the nature of error and design error causation in construction and engineering projects. A review of the normative literature revealed that design errors are caused by an array of factors that can work interdependently. A generic framework is developed that classifies design error according to people, the organization, and project is presented. The paper suggests that people, over and above organizational and project management strategies, have the greatest propensity to reduce errors through the process of situated learning and knowing. This is because the working environment provided by an organization and the processes used to deliver construction and engineering projects influence the nature and ability of people to undertake tasks. Consequently, there is no single but rather a multitude of strategies that need to be adopted in congruence to reduce design errors so that safety and project performance are ameliorated.