基于UML的软件体系结构开发方法

模型间的平稳过渡是软件系统开发的关键。然而,通常基于UML的软件系统的四种模型中,从用例分析模型到其它设计模型之间存在一条很难逾越的鸿沟。本文通过引入软件体系结构模型,提出了基于UML的软件体系结构开发方法,改进了模型间的平稳过渡问题。为了表明这个方法的可用性和有效性,我们陈述了库存管理系统应用的案例研究。     

电站除氧器的检验,修复及安全评估

通过全面检验,发现除氧顺给水箱封头焊缝和加强三角撑水平支撑点处有危险性裂纹等超标缺陷,针对裂纹进行挖补修复,并经无损检验合格后,再对除氧器进行强度校核、现状分析和经济性能分析,作出除氧器恢复额定参数运行的结论。修复后运行至今,未发现泄漏等异常情况,获得了可观的经济效益。     

裂解气压缩机的透平轴位移故障分析及改进

分析了裂解气压缩机透平GBT-201轴位移故障停车情况,说明了管网系统压力波动大时及轴位移变化大时联锁未能动作的原因。并提出了改进措施。     

栉孔扇贝急性病毒性坏死症病毒感染的ELISA检测

应用纯化病毒免疫新西兰兔制备的抗血清，进行ELISA分析，检测栉孔扇贝体内急性病毒性坏死症病毒的感染情况。结果表明：一龄贝在整个养殖期间感染该病毒呈现低一高一低的涨落过程，其中7月下旬到8月中旬检出阳性率为75％～95％，为当年感染的高峰时期。对二龄贝感染该病毒的分析结果显示，二龄贝对病毒的感染可能具有一定的抗性。     

Internet电话技术及其应用前景

文章介绍了 Internet 上话音传送技术的几种实现方式及电话网关的组成,预测了 Internet 电话市场的前景及其将对传统电话业务的影响。     

One-cycle control of three-phase active power filter with vector operation

Active power filters (APFs) provides an effective measure to eliminate the power line harmonic/reactive currents generated by nonlinear loads or by distributed energy sources that are connected to the grid. Active power filters are typically connected in parallel to the harmonic/reactive current sources and cancel the harmonic/reactive components in the line current so that the current flow into and from the grid is sinusoidal and in phase with the grid voltage. Since the APFs process only the harmonic/reactive power, their power-handling capability can be much higher than that of the cascade power-factor-correction methods. In this paper, the one-cycle control method is extended to control three-phase APFs. The proposed control approach employs one integrator with reset along with several logic and linear components to control a voltage-source converter to achieve three-phase unity power factor for the current to and from the power grid. No multipliers or sensors for the load current and the APF inductor current are required. Furthermore, there is no need to calculate the reference for controlling APF inductor current so that complicated digital computation is eliminated. The operation switching frequency is constant that is desirable for industrial applications. The proposed control approach features great simplicity, excellent harmonic/reactive current cancellation, and solid stability. It is a cost-effective solution for power quality control for electronic equipment, buildings, industrial facilities, ships, airplanes, distributed power generation stations, etc. All findings are supported by experimental results.     

汽油机颗粒捕集器低温环境失效诊断研究

探讨并验证了轻型汽车在低温环境下对汽油机颗粒捕集器（gasoline particulate filter,GPF）完成诊断要求的可行性,在-30℃到-10℃范围内的多种环境下进行试验,采集了发动机在低温下起动后GPF两端温度和压力信号数据,结果表明即使在-30℃的环境下,温度和压力传感器仍然能够正常工作,且GPF两端温度和压力数据的变化趋势与常温状态下相似,能够较好区分出GPF是否存在移除或破损的异常情况。     

Three-phase bipolar mode active power filters

In this paper, a unified constant-frequency integration control method for a three-phase bipolar mode active power filter is proposed. The proposed control method eliminates the use of any multipliers, the need of sensing three-phase load current, and the nontrivial task of calculating the harmonies and reactive current components, as required by previously reported control methods. By applying one-cycle control and sensing the mains line current, unity power factor and low input current distortion can be realized by one integrator with reset along with a few linear components such as flip-flops, comparators, and clock. The proposed controller is simple, robust, and reliable. All findings are supported by simulation and experiments     

泥沙吸附石油的实验研究

本文通过实验研究了河流泥沙（包括黄土）对石油乳化油吸附的基本规律，讨论了吸附等温关系及吸附量与含沙量、泥沙粒径、溶液盐度、温度等影响因素之间的关系，分析了吸附动力反应过程。为进一步研究吸附的随流变化规律奠定了基础     

配置蓄热装置对火电机组一次调频性能影响

高比例可再生能源接入给电力系统稳定性带来巨大挑战,同时知识经济时代对供电电能质量提出更高要求,电力系统调频问题逐渐凸显。火电机组是电力系统调峰调频的主力电源,其配置蓄热装置对系统调峰能力的影响已有较多的理论研究和实践验证。以300 MW机组为例,研究不同的蓄热装置配置方案对机组一次调频能力的影响。研究结果表明不同配置方案在不同时段对火电机组一次调频能力的影响不同。该研究对火电灵活性改造影响分析、电力系统一次调频缺口评估具有借鉴意义。