在NGOSS中综合应用策略管理和过程管理的方法

分析了NGOSS中策略管理和过程管理的互补性,研究了NGOSS中策略管理的策略间协作需求,提出了一种在NGOSS中综合应用策略管理和过程管理的方法,即运用过程管理来改进策略管理中存在的不足的方法,并对其进行了实验验证。实验证明,这种方法实现了NGOSS中策略之间的协作,改进了策略管理中存在的不足,实现了基于策略的“闭环”方式的管理系统,提高了NGOSS系统的管理功能。     

机械设计中零件公差的运用

本文分析了机械设计中零件公差的选择,探讨了机械设计中零件公差标准的适用范围与公差选用中需要注意的问题,论述了机械设计中零件公差的运用。     

中低压农网改造升级中的经验积累

随着经济的发展,中低压农网应用范围越来越广,解决了绝大多数农村的用电问题,带动了农村经济的发展。由于中低压农网较复杂,因此施工中必须注意多种事项。本文主要介绍了中低压农网改造升级中存在的问题及原因,并提出了中低压农网改造升级中的典型经验,希望可以给同类工程提供借鉴。     

OpenGL下的复杂建模转换和交互式动画

利用VC环境下OpenGL绘制三维模型的方法,解决了多媒体教学软件中动画的可交互性。详细介绍了如何实现将复杂模型从3DSMAX中转换到OpenGL中的过程,该方法克服了3DSMAX编辑动画的不可交互性,同时简化了OpenGL中建模的复杂性。另外,针对3DSMAX制作动画不可交互性的缺陷,还介绍了如何在VC中添加教学中要用到的交互式动画控制的步骤。     

一种无频带错位的小波包算法

研究了数字信号处理中的小波分析方法。基于多尺度分析的思想,提出了信号的小波分解及重构新算法和小波包算法。由于算法中采用了频移技术,在小波分解中避免了频率的折叠现象,同时在小波包算法中也解决了频带的错位问题。算法在工程中更具实用价值     

官地水电站右岸高低线工程施工安全监测措施及效果

在现代化的工程施工中,安全监测工作在工程施工中越来越重要。在官地水电站右岸高低干线工程施工中,实施了安全监测,采取了有效的安全监测措施．指导了现场安全施工,并取得了良好的效果。．     

数字化技术在铁基合金铜元素可见光谱分析中的应用

使用数字化可见光谱自动分析系统研究了铁基合金中Cu元素的可见光谱,制作了数字化彩色图谱,模拟了Cu元素可见光谱图。研究了铁基合金中Cu元素的Cu510.55分析谱线组的特征,给出了分析用谱图。研究了铁基合金中Cu元素的数字化分析技术,结果可用于铁基合金中Cu元素的定性、定量分析和牌号鉴别。     

铸态中铬硅铸铁价电子结构与M7C3体积分数

为提高中铬铸铁共晶碳化物中M7C3比例,研究了中铬硅铸铁(290Cr8Si2).建立了铸态中铬硅铸铁基体的价电子结构,运用固体与分子经验电子理论(EET)分析了中铬硅铸铁中Si的作用.分析和实验结果表明,中铬硅铸铁基体含C、Cr、Si的γ-Fe晶胞中,C原子与Si原子的结合力强于C原子与Cr原子的结合力,较高的含Si量降低了铸铁基体的含Cr量,提高了共晶碳化物的含Cr量,进而提高了共晶碳化物中M7C3的比例.耐磨损中铬硅铸铁(290Cr8Si2)共晶碳化物(M7C3 M3C)中M7C3占94.2%(体积分数),明显高于中铬铸铁(290Cr8Si1)共晶碳化物中的M7C3的71.7%(体积分数).     

乙烯裂解气压缩机安装

本文重点论述了大型乙烯工程施工中乙烯裂解气压缩机的安装程序及安装工序中主要操作要点,并对乙烯裂解气压缩机安装中存在的常见问题进行了分析,对常见问题的处理措施方法进行了论述。     

中滦煤化工二期工程焦系统除尘设备的改造

除尘设备在煤化工生产中起到了重要的作用,其设备的除尘效果直接影响到了煤化工产业的生产效率。另外在生产过程中,有效除尘也是保证生产环境的有效方式。中滦煤化工有限公司具有煤气净化、含一期干熄焦、废水处理、煤场等全部工艺,而除尘环节在生产中起到了重要的作用。本文主要介绍了中滦煤化工二期工程中焦系统焦三、焦四皮带除尘系统的改造方法及效果。     

Processing of nanocrystalline diamond thin films for thermal management of wide-bandgap semiconductor power electronics

High current densities in wide-bandgap semiconductor electronics operating at high power levels results in significant self-heating of devices, which necessitates the development thermal management technologies to effectively dissipate the generated heat. This paper lays the foundation for the development of such technology by ascertaining process conditions for depositing nanocrystalline diamond (NCD) on AlGaN/GaN High Electron Mobility Transistors (HEMTs) with no visible damage to device metallization. NCD deposition is carried out on Si and GaN HEMTs with Au/Ni metallization. Raman spectroscopy, optical and scanning electron microscopy are used to evaluate the quality of the deposited NCD films. Si device metallization is used as a test bed for developing process conditions for NCD deposition on AlGaN/GaN HEMTs. Results indicate that no visible damage occurs to the device metallization for deposition conditions below 290 °C for Si devices and below 320 °C for the AlGaN/GaN HEMTs. Possible mechanisms for metallization damage above the deposition temperature are enumerated. Electrical testing of the AlGaN/GaN HEMTs indicates that it is indeed possible to deposit NCD on GaN-based devices with no significant degradation in device performance.     

Al2 O3 陶瓷表面金属化

为了提高陶瓷与金属覆盖层的结合强度,较系统地研究了Al2O3(96%)陶瓷表面金属化过程,研究内容包括:陶瓷的表面刻蚀、表面催化、化学沉积条件等,综合分析了金属化层与陶瓷基体之间结合强度的影响因素,研究发现在熔融的NaOH浴中,可获得最佳刻蚀表面形貌,Al2O3(96%)陶瓷基片上化学镀层的最佳结合强度为25.0～32.5 MPa.为开发性应用提供了建设性的意见.     

Dielectric—metal structural phase transition in alkali halide crystals under conditions of extremely high pressures

The dielectric—metal structural phase transition in alkali halide metals under conditions of extremely high pressures is studied using the method of electron density functional (MDF). The values of metallization pressure are calculated for both infinite crystals and nano-size samples. The dimensional dependence of metallization pressure is revealed, namely, the dependence of the value of phase transition pressure on the initial size of crystal.     

Diagnostics of degradation processes induced by pulsed electric signals at the aluminum-silicon interface

Thermal conditions in an aluminum metallization stripe deposited onto a single crystal silicon substrate have been studied during the passage of single rectangular electric pulse with a current density of j < 8 × 10¹⁰ A/m² and a duration of τ = 100–1000 μs. Based on the results of this analysis, a method of diagnostics of the state of metallization contact systems and determination of the conditions of their safe operation is proposed.     

Degradation processes induced by nonstationary electric signals in metallization systems on silicon

The temperature regimes of operation of an aluminum metallization layer on a silicon plate have been analyzed for the passage of an electric pulse with a current density buildup rate of Δj/Δt ≤ 1.5 × 10¹⁴ A/(m² s). The temperature dynamics in this system has been calculated and compared to the experimental results. Degradation processes in the metallization layer-silicon structure have been observed, which are related to the formation of a liquid phase at the metal-semiconductor interface and the contact melting of a metallization layer under the conditions of nonstationary heating.     

Generation of dislocation loops in silicon near local heat sources

The thermal conditions created in an aluminum metallization layer on a silicon wafer by a rectangular current pulse are analyzed at pulse heights of up to 6 × 10¹⁰ A/m² and pulse durations from 50 to 10³ μs. The thermoelastic stress developing in silicon substrates as a result of unsteady-state heating of the metallization layer is calculated. The theoretically predicted formation of linear defects near thermal shock sources in silicon is confirmed by experimental data.     

Aluminum alloy film deposition and characterization

A flash evaporation system which utilizes a mechanism for feeding alloy wire onto a heated bar was used for the deposition of aluminum-silicon, aluminum-copper and aluminum-copper-silicon. The effect of deposition conditions and processing procedure on film composition and microstructure was determined. Particular attention was given to the film surface topography and the possible influence of deposition conditions, alloy composition, substrate type, thickness, annealing time and temperature and addition of oxide overlayers. Resistivity, and possible shorting of junctions in silicon as a consequence of silicon dissolution in the metallization, were considered as a function of alloy composition. Metal continuity over steps in the substrate was tested as a function of deposition temperature. These studies yielded recommendations, regarding the general use of alloy metallization on silicon devices and its specific use in two-level metallization configurations, which include: deposition at temperatures down to 275°C and at evaporation rates of about 0.4 g/min; the use of initial layer thickness down to 0.7 μ; post-deposition processing for aluminum-copper or aluminum-copper-silicon not to exceed 525°C; the addition of 1% silicon to prevent junction penetration; and the addition of 4% copper to lend adequate electromigration resistance and inhibit hillock growth during high temperature processing.     

Analysis of the interactions in the Cu-Ti-diamond and Co-W-diamond systems in wetting diamond polycrystals and infiltration of UDD diamond nanopowder at high pressure and temperature

The regularities of the diamond-metal alloy interaction of the copper-titanium and cobalt-tungsten systems under diamond thermodynamic stability conditions have been considered. The possibility has been studied of the metallization of diamond polycrystals and composites when sintered in a high-pressure apparatus.     

Phase transformations in metallization systems under conditions of nonstationary thermal action

First-order phase transitions induced in aluminum metallization layers by the passage of single rectangular current pulses with amplitude up to 8 × 10¹⁰ A/m² and durations within 100–1000 μs are considered. The formation of local fused zones and their subsequent migration during current passage have been experimentally studied. The main mechanisms of interphase boundary propagation due to heat evolution at the solid/liquid interface under conditions of nonstationary heating of the metal film are established. The velocity of liquid-phase propagation (～25 m/s) along the metallization stripe has been determined in experiment and a method of calculating the length of a fused zone upon the current pulse passage is proposed.     

Effect of ferrite magnonic crystal metallization on Bragg resonances of magnetostatic surface waves

It is experimentally established that metallization of the surface of a ferrite magnonic crystal destroys the Bragg resonances of magnetostatic surface waves by violating the conditions of phase synchronism of the incident wave and that reflected from the periodic surface structure.