基于需求模型的航天软件测试用例生成方法

为了提高航天软件测试的效率和覆盖率,增加航天软件测试的有效性,提出了一种基于需求模型的软件测试用例设计方法。针对航天软件测试的特点,该方法采用从用例层深入至步骤层的测试优化策略。首先,基于元建模方法定义了一种测试需求模型;通过建立模型,将测试需求加以拆分,获取了测试需求之间的先后依赖关系以及测试需求与测试步骤之间的对应关系。然后,基于测试需求模型,构建了测试需求的路径图,进而通过对图的遍历获得了测试用例。最后,将该方法用于工程实践进行了实验验证。验证结果表明,该方法有效保证了测试活动的充分性和有效性,降低了测试用例约简的风险。与不约简的测试方法相比,该方法减少测试工作量达18%,减少测试用例数量为40%以上,软件测试的执行时间也减少了40%以上,在满足需求覆盖率的同时,有效提高了测试效率。     

Microstructure and mechanical properties of Al-Fe-V-Si/SiCp composites

The characteristics of microstructures and mechanical properties of the multi-layer spray deposited SiCp/A1-6.SFe-0.6V-1.3Si, SiCp/A1-8.SFe-1.3V-1.7Si and SiCp/Al-10Fe-1.3V-2Si composite sheets obtained by rolling after extruding were investigated. The evolution of the grain and phases of these composites during processing were examined, and the influence of the microstructures on the mechanical properties was analyzed. The experimental results show that the ultimate tensile strengths σb of the three kinds of composite sheets are 420, 535, 470 MPa respectively at room temperature, and 232, 285, 300 MPa at 315℃ and 148, 180, 200 MPa at 400 ℃. The excellent mechanical properties can be attributed to the high solid solubility, fine grain size, Al12（Fe,V）3Si precipitation particles and the SiC particles. And the composition of the matrix alloy has an obvious effect on the mechanical properties of the as-rolled sheets.     

A comparative multicenter study of two transdermal estradiol replacement therapies in the treatment of postmenopausal symptoms

OBJECTIVE: Comparison of the effects of treatment of two transdermal therapeutic systems for estrogen replacement therapy with regard to efficacy, tolerability, and acceptance. DESIGN: Open randomized. SETTING: Multicenter. PATIENTS AND INTERVENTIONS: A study population of 104 postmenopausal women was randomized on a 1:1 basis to treatment with one of two estradiol patches, System (Cilag) and Estraderm (Ciba-Geigy). OUTCOME MEASURES: Systolic and diastolic BP, hot flushes, night sweating, fatigue, insomnia, depression, nervousness, headache, vaginal discomfort (efficacy variables); bleeding, dermatological symptoms, comfort and adhesiveness of patch, and other possible causes of discontinuation (tolerability); general evaluation by patient (acceptance). RESULTS: Considering all efficacy variables, 53% of Systen and 46% of Estraderm patients found the therapy satisfactory. Tolerability was somewhat higher in the Systen group. Adhesiveness of the patch was significantly better for Systen. Overall, 79% of Systen patients and 62% of Estraderm patients evaluated treatment as "good" or "very good." The majority of patients in both groups found the patch very comfortable or only slightly obtrusive.     

山药-蛹虫草双向发酵的抗氧化活性增效性

本实验研究山药-蛹虫草（Cordyceps militaris）双向发酵的抗氧化活性增效性。以超氧阴离子自由基清除率、2,2-二苯基-1-苦基肼自由基清除率和羟自由基清除率为指标，比较分析山药-蛹虫草菌质和山药基质的抗氧化活性。通过抗氧化活性成分含量测定以及高效液相色谱指纹图谱、扫描电子显微镜和傅里叶变换红外光谱分析，研究菌质抗氧化活性的增效原因。结果表明：发酵结束后菌质的自由基清除率显著高于山药的自由基清除率（P＜0.05），菌质中总酚、总黄酮和总皂苷含量显著高于山药（P＜0.05）；菌质不仅含有一些山药中不存在的成分，而且山药中原有6 种成分的含量也发生明显变化；蛹虫草菌丝对山药结构有分解作用；山药中的多糖、纤维素等糖类物质作为碳源被蛹虫草所代谢，转化成多酚类、皂苷类物质。本研究发现，山药-蛹虫草发酵体系在抗氧化活性方面具有增效性，菌质成分的种类、含量变化以及菌质微观结构变化是产生抗氧化活性增效性的主要原因。     

世茂深坑酒店钢结构设计

系统介绍了世茂深坑酒店的钢结构设计,着重阐述了该结构的关键节点设计,对酒店钢结构框架进行了施工过程分析.结果表明:结构上端有很强的约束,刚度较大,宜选取延性较好的钢框架-支撑结构；楼板刚度对结构构件受力有显著影响,构件设计时须取不同楼板刚度计算模型下的包络结果；采用带肋钢铺板组合楼板可有效解决混凝土板受拉问题.     

超声法提取藏药唐古特乌头中多糖的研究

采用L9(34)正交实验对藏药唐古特乌头中多糖的超声提取工艺进行了优化。以葡萄糖为标准品,用硫酸-苯酚法测定藏药唐古特乌头水提物中可溶性多糖的含量。得到了用超声法提取唐古特乌头中多糖的最佳工艺条件为:药材粒度8目、料液比(质量比)1∶16、提取时间2 h,此条件下提取液中多糖含量可达4.03%。研究结果表明该工艺稳定可行。     

北方寒冷地区桥面防水层施工工艺研究

结合内蒙古通辽-下洼高速公路教来河大桥桥面铺装实体工程,简要介绍了桥面防水层的施工概况,总结了涂膜类防水材料的施工工艺,为北方寒冷地区公路桥面防水层施工提供一定的参考依据。