惯导仿真训练系统的研究

采用面向对象的软件建模思想、模块化的软件设计思想和多种相关技术,设计实现了"惯性导航仿真训练系统"。该系统是一个能训练领航员熟练操作惯导及领航技能的软硬件结合的仿真训练系统。文章对系统的设计原则、构成及实现方法进行了阐述,给出了测试航线图,并实现了与其他模拟器的组网对接。     

层状SiC/BN陶瓷的制备及抗冲击性能

为发展高性能结构功能一体化的新型陶瓷装甲防护材料,采用流延法结合热压烧结法制备了不同结构设计的层状SiC/BN陶瓷,研究了材料的烧结特性、显微结构、力学性能及抗冲击性能.结果表明:层状结构设计可以实现陶瓷材料的强韧化效果,其失效模式为非脆性断裂,保持结构完整性的能力明显提升;弯曲强度410 MPa,断裂韧性7.6 MP...     

基于Matcom的航天电子设备遥测参数预测

对大型航天电子设备的遥测参数进行预测分析可以在早期及时发现设备性能异常.论文中利用Matcom的矩阵计算功能,使用VC＋＋开发了最小二乘支持向量机（LS-SVM）等多种预测算法,实现了对大型航天电子设备遥测参数的预测,有助于对设备性能预示分析和对异常及时有效处理.     

Risk assessment in service provider communities

Online service delivery undertaken between clients and service providers often incurs risks for both the client and the provider, especially when such an exchange takes place in the context of an electronic service market. For the client, the risk involves determining whether the requested service will be delivered on time and based on the previously agreed Service Level Agreement (SLA). Often risk to the client can be mitigated through the use of a penalty clause in an SLA. For the provider, the risk revolves around ensuring that the client will pay the advertised price and more importantly whether the provider will be able to deliver the advertised service to not incur the penalty identified in the SLA. This becomes more significant when the service providers outsource the actual enactment/execution to a data centre — a trend that has become dominant in recent years, with the emergence of infrastructure providers such as Amazon. In this work we investigate the notion of “risk” from a variety of different perspectives and demonstrate how risk to a service owner (who uses an external, third party data centre for service hosting) can be managed more effectively. A simulation based approach is used to validate our findings.     

海上吊机超高强结构钢Corus RQT 701的焊接

针对用于建造海上吊机超高强低碳低合金调质钢Corus RQT 701焊接难度较大、容易产生焊接缺陷和韧性下降的倾向,本文选用超低氢型药芯焊丝Out shield 690-H进行混合气体保护焊试验。通过合理控制预热温度、道间温度、焊接电流、电弧电压、焊接速度等工艺参数,有效控制焊接热输入,最终获得母材与焊材熔合良好、无焊接缺陷、具有优良力学性能,特别是低温冲击韧性的焊接接头,为制定合理焊接工艺提供了有力依据。     

Pyrolysis of Sedum plumbizincicola,a zinc and cadmium hyperaccumulator: pyrolysis kinetics,heavy metal behaviour and bio-oil production

Appropriate disposal of hyperaccumulator biomass is a problem inhibiting the widespread use of phytoremediation technology. In the present study, kinetic analysis of the pyrolysis process of Sedum plumbizincicola, the behaviour of heavy metals and bio-oil composition were studied. The kinetic analysis of the pyrolysis process shows that activation energy (E) changed from 150 to 186 kJ mol⁻¹ and the frequency factor (A) changed from 1.34 × 10¹¹ to 8.99 × 10¹⁵ s⁻¹. At temperatures of 450–750 °C more than 66.3 % of zinc (Zn) remained in the char. More than 87.6 % of the cadmium (Cd) was found in the bio-oil. Pyrolysis at 650 °C led to the highest yield of alkanes with low-oxygen compounds found in the bio-oil. Pyrolysis at 650 °C can likely offer a valuable processing method for S. plumbizincicola and recovery of Zn from the char and recovery of Cd from the bio-oil will be attempted in future research.

     

Phosphate removal from water using an iron oxide impregnated strong base anion exchange resin

Removing phosphate from water is important as it causes eutrophication, which in turn has a harmful effect on aquatic life, resulting in a reduction in biodiversity. On the other hand, recovery of phosphate from phosphorus containing wastewater is essential for developing an alternative source of phosphorus to overcome the global challenge of phosphorus scarcity. Phosphate removal from aqueous solutions was studied using an iron oxide impregnated strong base anion exchange resin, Purolite FerrIX A33E in batch and fixed-bed column experiments. Phosphate adsorption in the batch study satisfactorily fitted to the Langmuir isotherm with a maximum adsorption capacity of 48 mg P/g. In the column study, increase in inlet phosphate concentration (5–30 mg P/L), and filtration velocity (2.5–10 m/h) resulted in faster breakthrough times and increase in breakthrough adsorption capacities. Increase in bed height (3–19 cm) also increased adsorption capacity but the breakthrough time was slower. The breakthrough data were reasonably well described using the empirical models of Bohart–Adams, Thomas, and Yoon–Nelson, except for high bed heights. Phosphate adsorbed was effectively desorbed using 1 M NaOH and the adsorbent was regenerated after each of three adsorption/desorption cycles by maintaining the adsorption capacity at >90% of the original value. Greater than 99.5% of the desorbed P was recovered by precipitation using CaCl₂.     

The effects of polyethylene glycol (PEG) as an electrolyte additive on the corrosion behavior and electrochemical performances of pure aluminum in an alkaline zincate solution

The effects of zinc oxide and/or polyethylene glycol (PEG) as electrolyte additives on the corrosion and electrochemical performances of pure aluminum in 4.0 M KOH solutions were investigated by means of hydrogen collection, polarization curve, galvanostatic discharge, scanning electron microscopy (SEM), and energy dispersive analysis of X‐ray (EDAX). The addition of ZnO markedly inhibited the corrosion of aluminum in 4.0 M KOH solutions, resulting from the deposition of zinc with high hydrogen evolution overpotential in aluminum surfaces. The introduction of PEG in the alkaline zincate solution obviously improved the deposition of zinc by increase in the overpotential of zinc deposition, thus the corrosion rate of aluminum in the alkaline zincate solutions with PEG was further decreased. The enhancement effect of PEG on the inhibition of zinc oxide first increased and then decreased with increasing the content of PEG in the electrolyte. The electrolyte system with 0.2 M ZnO and 2.0 mM PEG presented the highest inhibition efficiency (98.8%) for the corrosion of aluminum. The results of galvanostatic discharge indicated that the aluminum anode shows excellent discharge performances in the 4.0 M KOH solution with 0.2 M ZnO and 2.0 mM PEG.