中国铝用氟化盐的危机与前景

从中外铝业的状况出发论述了世界铝用氟化盐的产能、产量、供需状况、面临的问题、发展趋势及前景,指出铝用氟化盐的产能未来还将进一步向中国集中,依托资源和市场两大因素,通过加强管理和技术创新,不久的将来中国将由现在的铝用氟化盐生产大国变为真正的世界强国。     

The recycle of wrought aluminum alloys in Europe

Increasing demand for aluminum-based products and globalization of the aluminum industry have contributed significantly to the higher consumption of aluminum scrap for re-production of wrought aluminum alloys. The recycling of wrought auminum alloys not only fills market demand, but does so economically. It is a well-known fact that recycling wrought aluminum alloys from collected scrap consumes 15 times less energy than producing primary aluminum, and the cost of internal scrap is marginal. This paper examines opportunities for recycling scrap to solve the ongoing problem of raw material shortages for European producers of wrought aluminum alloys.     

钢铁业产能过剩亟待启动市场杠杆

为应对国际金融危机的冲击和影响,国家制定和实施了扩大内需、促进经济增长的一揽子计划,出台了钢铁产业调整和振兴规划。目前,政策效应初步显现,钢铁产业发展总体向好,但也出现了产能过剩、重复建设等问题。为了抑制钢铁业产能过剩的问题,政府通过宏观调控为产业发展创造有效竞争环境,通过市场竞争杠杆实现最终产销平衡。     

An approach to higher damping capacity based on a control theory strategy

In order to compare the active damping (computer-controlled damping) via a control theory with the passive (material) damping, the vibration suppressing effect has been investigated by constructing a feedback control system. It consists of a cantilever beam (3×35×300 mm³), a sensor, an actuator and a feedback controller, which has been designed on the basis of the optimal regulator control theory. In a freely decaying vibration state, the active damping effect increases the vibration damping capacity (Q⁻¹) from 0.011 to 0.157 (almost 14.3 times). On the other hand, in a resonant state, the active damping reduces the resonant amplitude to about 1/12. The active damping corresponds to about 6.8 times the maximum damping observed in the ferromagnetic metal SIA.     

我国不锈钢管的市场供需情况及其特点

介绍了我国不锈钢管的消耗量、生产量及进口量情况。详细分析了化工、石化、电力等行业用不锈钢管的品种、规格、数量 ;分析了我国不锈钢管的生产能力与市场需求情况 ,指出无缝管开发“新品” ,焊管开发“精品”是今后市场需求之趋向。     

翻新能力有限的混合系统多产品批量模型

为确定各产品的制造与翻新策略,对翻新能力有限的混合系统进行研究.在此系统中,制造和翻新多种产品.每种产品在顾客使用后都会以恒定速率返回,但因翻新能力有限,部分返回旧产品因不能用于翻新而被处置.顾客对每种产品的需求恒定且由服务性产品库存来满足,服务性产品库存由制造品和翻新品组成,不允许缺货.在(M,1)策略下构建了库存决策模型,应用拉格朗日乘数法和贪婪算法分别确定了各种产品的翻新顺序和翻新比率.对既定的翻新比率,提出了制造准备次数为正整数时各种产品制造与翻新策略的求解程序,得到了各产品的制造和翻新批量、制造和翻新准备次数等求解公式.算例表明,在(M,1)策略下,一旦各产品的翻新顺序和翻新比率确定,可以找到各产品最优的制造与翻新策略.     

Optimal control of reassembly with variable quality returns in a product remanufacturing system

We consider the assembly system of modular products in the remanufacturing environment subject to used module returns with uncertainties in terms of timing, quantity and quality. n customer demand classes of remanufactured products are classified by l = 1,…,n levels of product quality. Returned modules arrive according to a compound Poisson process and each demand class follows an independent Poisson process. Returned modules can be stocked for reassembly upon demand requests, but incur a holding cost. We formulate the problem as a Markov decision process and show that the reassembly and inventory control policy is a state-dependent threshold type policy.     

虚拟共享--边界模糊化趋势下的企业创新模式

虚拟企业与共享服务是两种适应科技进步和经济发展的新型企业组织形式.从组织模式上看,虚拟企业和共享服务分别为企业外部市场半内部化和内部组织半市场化的两种形态.文章提出"虚拟共享"的思想,并指出随着企业边界的模糊化趋势的加强,虚拟企业和共享服务两种形态将走向这种全新的组织创新模式.     

Corrosion and life cycle management of port structures

Corrosion damages due to splash zone corrosion, concentrated corrosion and salt-induced corrosion have been observed worldwide. Coating is applied to splash zone. Cathodic protection is required for prevention of concentrated corrosion, and both coating and cathodic protection are necessary to prevent salt-induced corrosion. To avoid unexpected large-scale rehabilitation measures as a consequence of negligence of periodic maintenance, systematical planning and budgeting of maintenance activities are necessary. Life cycle management (LCM), and its whole life costing (WLC), will contribute to a realistic approach of maintenance policy.     

Φ60mm毛管的开发

介绍了在Φ 50mm机组上通过适当改进生产Φ 60mm毛管,可充分发挥机组能力,达到节能增效、适应市场需求的目的。     

On optimal position control of mechanisms in rolling processes

The paper deals with a feedback system created with the use of the method of regular synthesis of optimal control system which should bring a non-linear and discontinuous planar object to a moving target in a minimum time. In real, practical circumstances, on this system there impinge perturbations such as unexpected and undefined motion resistances variations, parameter changes and errors in measurements of states, which cause that the created time-optimal closed-loop system may generate limit-cycles and may be stopped in other state than the required final one (target). There is shown that while using adequately so called F-solution of discontinuous differential equation, the synthesised closed-loop system may become insensitive towards above mentioned perturbations. Some suggestions are made as to practical application in position devices in reversing rolling mills     

2007年钼市场回顾与展望

回顾了2007年钼市场走势。从2007年中国国内钼产量以及价格、进出口、政策等方面,对国内以及出口钼市场进行了总结和分析。进入2007年以后,国家加强了对资源产品的管理和调控力度,钼品出口配额政策的出台以及出口关税的增加,抬高了钼品出口的门槛。国家政策在对出口市场造成影响的同时,也给国内市场带来了机遇和挑战。预计2008年的钼品供需关系依旧紧张,钼品价格仍将高位运行。     

建厂三十年的浦项钢铁公司及其经营特征

概述韩国浦项钢铁公司概况,包括现有设备、海外投资项目和对占领中国市场的策略,以及公司近几年生产、销售和赢利情况;探讨该公司发展取得成功的经营特征;并介绍该公司1998年的经营方针和管理目标为继续维持高生产率和大量销售传统,采取紧缩政策,建立“经济增值”先进管理技术和“全球共同文化”。     

机加车间加工资源能力成本分析研究

加工资源能力成本分析对机加车间管理至关重要。论文首先阐述了基于加工资源费率的成本分配过程，建立了加工资源能力模型，定性分析了生产中的不确定性因素，接着，基于加工资源费率的成本分配过程，详细分析了单加工资源和多加工资源的成本损失，并且提出基于约束理论的多加工资源组成的生产系统的物流平衡性的评判指标；在能力分析的基础上，讨论了能力模型中的各种非生产能力的成本归属问题和能力分析作用的两面性。最后，结合某模具车间的实际情况，成功开发了成本管理系统。利用提出的能力分析方法对车间某核算期间进行了详细分析。实践证明，提出的加工资源能力分析方法有效、合理，对生产资源配置能起到很好的指导作用。     

钢结构用方矩形钢管的市场分析和应用前景

概述了大规格方矩形钢管和圆形钢管作钢结构梁(柱)时的力学特性,方矩形钢管的市场分析及其技术装备水平。分析指出,当前我国方矩形钢管生产线的产能扩张已大于市场容量的增长速度,需要转变发展观念;其发展方向应当从数量扩张型向质量创新型转变。     

Method for the application of deep reinforcement learning for optimised control of industrial energy supply systems by the example of a central cooling system

This paper presents a method for data- and model-driven control optimisation for industrial energy supply systems (IESS) by means of deep reinforcement learning (DRL). The method consists of five steps, including system boundary definition and data accumulation, system modelling and validation, implementation of DRL algorithms, performance comparison and adaptation or application of the control strategy. The method is successfully applied to a simulation of an industrial cooling system using the PPO (proximal policy optimisation) algorithm. Significant reductions in electricity cost by 3% to 17% as well as reductions in CO₂ emissions by 2% to 11% are achieved. The DRL-based control strategy is interpreted and three main reasons for the performance increase are identified. The DRL controller reduces energy cost by utilizing the storage capacity of the cooling system and moving electricity demand to times of lower prices. Additionally, the DRL-based control strategy for cooling towers as well as compression chillers reduces electricity cost and wear-related cost alike.     

油井管供需形势分析与对策

能源及石油工业的发展使其对油井管的需求不断增加。介绍了国内外油井管的需求情况;论述了国外油井管发展概况和我国油井管产能及现状。在此基础上对油井管供需形势进行了综合分析,认为国内油井管市场总体上供大于求,国际市场容量有限,并且我国在油井管出口贸易方面存在一些深层次问题。提出了调整产品结构、加强行业自律和协调、提高产业集中度等对策。     

精益生产在精冲车间的应用

为提高国内精冲行业的生产管理水平,对精益生产在精冲车间的应用进行了研究。对精冲车间进行调研之后发现,工厂目前存在参数难以持续优化、排产订单应变差、生产过程数据获取实时性差等问题。据此,提出了一种在精冲车间应用精益生产的管理模式,基于该模式,使用Microsoft Visual Studio 2013 C#和Microsoft SQL Server 2014开发了一套精冲车间精益生产管理系统。与传统生产管理方式相比,该系统根据精冲生产及行业需求特点,通过数据库分析,能够持续对工艺的生产参数、创新工艺技术进行优化,提高生产能力。采用智能排产技术后,车间能够从容地应对由于市场波动引起的订单变化,降低了中间库存,有效地提升了生产管理效率,有利于国内精冲行业的可持续性发展。     

发展我国的无缝钢管连轧设备

连轧管机组近几十年因其具有产量高、轧管质量好等优点而得到快速发展。介绍了我国连轧管设备的现状和“九五”期间有关连轧管机的研究成果。指出了按照钢管规格组距建设适应市场的专门化机组以期形成有经济规模的生产力,是我国连轧管机组的发展方向。     

基于智能前馈自学习的数控机床永磁电机控制优化策略

数控机床的主轴驱动系统决定了机床的动态特性、加工精度等关键技术指标,其核心部件永磁同步电机的控制精度及稳定性必须进行优化。在传统PI反馈控制的基础上提出一种基于在线智能前馈补偿自学习的优化控制方法。该在线智能前馈补偿控制使用简单迭代学习规则,以补偿重复负载转矩和模型参数的不确定性,无需对系统模型进行辨识。推导证明了此优化策略可满足系统响应的稳定性和收敛性要求。实验结果也证明了该优化策略的有效性和可行性,可为数控机床的主轴驱动系统优化设计提供参考。