碳酸化分解工艺的改进与实践

本文针对烧结法生产氧化铝过程中,铝酸钠溶液的碳酸化分解工艺,由间断分解到连续分解的改进进行了论述,指出连续分解是碳酸化分解的发展方向。     

ZJ510L-B汽车用高强度热轧板的试制

珠钢150t电弧炉-LF(VD)-CSP(紧凑式带材生产)流程试生产的5～8mm ZJ510L-B(0．16C--1．22Mn)汽车用高强度热轧板的铁素体晶粒尺寸为6．0～9．2μm，带状组织为1．5～2．5级，强度极限σb562～610MPa，延伸率δ5 32．0％～38．6％。文中还分析和提出了带状组织的形成原因和改进措施。     

Industrialization of High Performance Sintered NdFeB Magnets

Sintered Nd-Fe-B magnet was manufactured by advanced equipment via a SC (Strip casting) technology.It has integrative performance.     

对国企人才资源管理的几点思考

人力资源管理中的人才资源管理是现代企业面临的一个重大挑战。国企中的人才资源管理需要不断进行观念创新，正确认识人才的流动，人才的识别选拔、人才的能上能下、人才的文化物质需求、人才的培育评价、人才的使用储备。     

X-ray-based measurement of composition during electron beam melting of AISI 316 stainless steel: Part II. Evaporative processes and simulation

An energy dispersive X-ray (EDX) detector mounted on a laboratory scale electron beam furnace (30 kW) was employed to assess the potential use of X-rays as a means of on-line composition monitoring during electron beam (E B) melting of alloys. The design and construction of the collimation and protection systems used for the EDX are described in Part I. In Part II, a mathematical simulation of the heat, mass, and momentum transfer was performed for comparison to the EDX and vapor deposition results. The predicted flow patterns and evaporation rates are used to explain the differences between the two experimental methods. For the EDX spectra measured, the X-rays generated were from the center of the hearth where fluid flow rising from the bulk of the pool is sufficient to maintain the bulk composition despite the high evaporative flux from the surface. The flow moves radially outward from the center of the pool, with the volatile species being depleted. The vapor deposition technique measures the entire region, giving an average surface composition, and it therefore differs from the EDX results, which gave a near bulk composition. This combined study using in-situ EDX measurements and numerical simulations both provided an insight into the phenomena controlling the evaporation in an EB-heated system and demonstrated the viability of using EDX to measure the bulk composition during EB melting processes.     

On the relationship between parity space and approaches to fault detection

Parity space approach and H₂ approach are two important fault detection approaches. This paper studies the relationship between these two approaches, which reveals frequency domain characteristics of the optimal solution of the parity space approach on the one side and provides a numerical solution of the H₂-optimal design of residual generators on the other side.     

电信服务营销渠道转型的必要性

分析了电信企业服务营销渠道的特点、旧有的服务营销渠道模式和存在的问题以及今后电信业和市场等方面发展的新需求，对电信服务营销渠道转型的必要性进行了探讨和研究,同时提供了一个可供参考的服务营销渠道价值评估体系架构,从量化服务营销渠道对电信企业贡献价值的角度论述了服务营销渠道转型的必要性。     

揭密电信市场的价格套餐

随着中国电信市场的改革，激烈竞争的局面已经形成。价格战是最直接、最快速应对竞争的方法。根据博弈论分析，一方降价，另一方也必然会降价。但如何降价，如何制订各种价格套餐，同时又使价格战带来的损伤最小，这两者之间是一个均衡的过程。运营商要在其中作出艰难的选择：自己的收入盈亏点在哪里?价格应该比竞争对手低多少，如果给客户优惠，怎样优惠?等等。     

Effect of exponentially graded base doping on the performance ofGaAs/AlGaAs heterojunction bipolar transistors

The authors have fabricated n-p-n GaAs/AlGaAs heterojunction bipolar transistors (HBTs) with base doping graded exponentially from 5×10¹⁹ cm^-3 at the emitter edge to 5×10¹⁸ cm^-3 at the collector edge. The built-in field due to the exponentially graded doping profile significantly reduces base transit time, despite bandgap narrowing associated with high base doping. Compared to devices with the same base thickness and uniform base doping of 1×10¹⁹ cm^-3 , the cutoff frequency is increased from 22 to 31 GHz and maximum frequency of oscillation is increased from 40 to 58 GHz. Exponentially graded base doping also results ill consistently higher common-emitter current gain than uniform base doping, even though the Gummel number is twice as high and the base resistance is reduced by 40%     

Orientation-based unique representation for planar curves and shapes

This paper presents an orientation-based representation for planar curves and shapes. The new representation can uniquely represent all types, of planar shapes, be it convex, nonconvex, polygonal, smoothly curved, or piecewise smooth shapes. It is based on a new parameterization, theabsolute integral orientation. This representation is invariant under translation and rotation. The absolute integral orientation is a parameter invariant under scaling. As a result, matching of similar shapes (i.e., determination of the relative orientation and the scaling factor) using the absolute integral orientation as the parameter is easier than using the arclength as the parameter. In addition, the new representation has the feature of adaptive sampling, making it more compact and efficient than arc-length-based representations.