design and implementation of multi-role requirement review system

需求质量对于软件产品质量有至关重要的影响,而需求评审是保证需求质量的有效手段之一.目前的需求评审存在效率低、问题发现率不高、评审结果难以被有效处理等问题.在对需求特性进行研究,以及对实际项目中人员角色及其关注点进行调研的基础上,开发了多角色的需求评审系统MRRS.MRRS系统为每类角色的评审人员提供有针对性的评审指标体系,依照预设算法对评审结果进行量化处理,以GUl形式展示结果,为项目决策提供支持.应用了MRRS系统后,评审效率提高一倍以上

一种烯烃与苯生产烷基苯用的沸石催化剂及其制备

一种用于由低浓度烯烃与苯生产烷基芳烃催化剂由β沸石、卤素和惰性组份构成，其中SiO2/Al2O3摩尔比为15～45的β沸石为25～90％，卤素为0.05～0.48％，其余为惰性组份。该催化剂的酸特点是每克催化剂总酸量为10×1020～20×1020个，其中中强酸中心和弱酸中心的比例为80∶20～60∶40。该催化剂用于乙烯和苯的液相烷基化生产乙苯过程，可以降低生产成本，提高产品质量，生产出纯度大于99.8％的乙苯，其中二甲苯含量小于100ppm。带填

比较经颅超声造影和数字减影血管造影对大脑中动脉狭窄的诊断价值研究 Diagnostic Value of Transcranial Contrast-enhanced Ultrasound and Digital Subtraction Angiography for Middle Cerebral Artery Stenosis

【摘要】 目的 比较经颅超声造影（transcranial contrast-enhanced ultrasound，t-CEUS）和DSA在大脑中动脉（middle cerebral artery，MCA）狭窄性疾病中的诊断价值。 方法 收集2017年12月-2019年4月疑似MCA狭窄或闭塞的患者197例，记录其225条狭窄或闭塞的大脑中动脉的t-CEUS和DSA检查结果。根据MCA狭窄程度分为轻度狭窄（30%～50%），中度狭窄（50%～69%），重度狭窄（70%～99%）和闭塞（100%），以DSA为金标准，分析t-CEUS对轻、中和重度MCA狭窄的诊断价值。 结果 197例疑似MCA狭窄闭塞患者中，男132例，女65例，年龄43～72岁，平均（58.4±4.6）岁。经DSA确诊的狭窄和闭塞的225条MCA中，轻度狭窄16条，中度狭窄70条，重度狭窄121条，闭塞18条。t-CEUS诊断狭窄和闭塞的共224条MCA，其中，轻度狭窄18条，中度狭窄76条，重度狭窄112条，闭塞18条。t-CEUS和DSA诊断MCA狭窄和闭塞高度吻合（Kappa=0.91）。t-CEUS诊断轻度MCA狭窄的敏感度、特异度和准确度分别为80%、80%和91%；诊断中度MCA狭窄的敏感度、特异度和准确度分别为83%、93%和97%；诊断重度MCA狭窄的敏感度、特异度和准确度分别为83%、96%和96%。 结论 t-CEUS能够清楚地显示轻、中、重度MCA狭窄和闭塞，适用于MCA狭窄和闭塞类疾病患者的确诊，尤其是适用于不适合DSA检查的疑似MCA狭窄和闭塞患者。 【Abstract】 Objective To investigate the diagnostic value of transcranial contrast-enhanced ultrasound (t-CEUS) and digital subtraction angiography (DSA) for middle cerebral artery (MCA) stenosis or occlusion. Methods A total of 197 patients with suspected MCA stenosis or occlusion from December 2017 to April 2019 were enrolled. A total of 225 stenostic or occluded MCAs were diagnosed by t-CEUS and DSA, according to the degree of MCA stenosis, the MCAs were divided into four groups: mild (30%-50%), moderate (50%-69%), severe (70%-99%) and occlusion (100%). Taking DSA diagnosis as the golden standard, the specificity, sensitivity, and accuracy of t-CEUS diagnosis were analyzed by comparing the results of ultrasound imaging. Results Of all the 197 patients, 132 male and 65 female, with the average age (58.4+4.6) years and the range 43 to 72 years. Of 225 MCAs diagnosed by DSA, 16 MCAs were mild, 70 were moderate, 121 were severe, and 18 were occluded. Of 224 MCAs diagnosed by t-CEUS, 18 were mild, 76 were moderate, 112 were severe, and 18 were occluded. The diagnosis of MCA stenosis/occlusion using t-CEUS and DSA had a high consistency (Kappa=0.91). The sensitivity, specificity and accuracy of t-CEUS for the diagnosis of mild MCAs were 80%, 80%, and 91%, respectively; the sensitivity, specificity and accuracy of t-CEUS for the diagnosis of moderate MCAs were 83%, 93%, and 97%, respectively; the sensitivity, specificity and accuracy of t-CEUS for the diagnosis of severe MCA were 83%, 96%, and 96%, respectively. Conclusions t-CEUS can clearly show mild, moderate and severe stenosis and occlusion in MCAs, and it is suitable for the diagnosis of patients with MCA stenosis and occlusion, especially for the patients with suspected MCA stenosis and who are not suitable for DSA

β-葡萄糖苷酶高产菌株及其应用研究

对Hypocreasp．W63的β-葡萄糖苷酶酶学性质研究表明，该酶液体发酵最高酶活高达482．1U／mL，最适反应pH值为4．8，最适反应温度为65℃；乙醇体积分数为10％时对酶活有最大促进效果，乙醇耐受能力高达30％；将该酶应用于同步糖化发酵研究中，发现发酵至120h乙醇质量浓度可高达41．25g/L，与对照相比，乙醇产量均提高近2倍。该菌株所产的B一葡萄糖苷酶较高的酶活力、耐热性能、乙醇耐受性和同步糖化发酵促进效果，预示着该菌在纤维素乙醇产业化应用中具有广阔的应用前景

400 Gbit/s 286 km超长站距无中继传输系统研究

为将400 Gbit/s高速率应用于超长站距无中继光传输系统,首先对400 Gbit/s双偏振-四进制正交幅度调制（DP-16QAM）及400 Gbit/s双偏振-八进制正交幅度调制（DP-64QAM）两种高阶调制码型及其对应的光信噪比（OSNR）要求进行了研究,然后通过实验研究了两种码型背靠背OSNR的要求及入纤光功率与误码率的关系,最后搭建了具有前后向拉曼放大器的400 Gbit/s超长距光传输链路,通过实验测试了两种码型对应的最远单跨传输距离。实验结果表明,400 Gbit/s DP-16QAM在G.652光纤上利用双向拉曼光放大器最远可以传输286 km,对于电力长跨距来说基本满足了大部分的应用场合

葡萄糖苷酶高产菌株及其应用研究

对Hypocreasp．W63的β-葡萄糖苷酶酶学性质研究表明，该酶液体发酵最高酶活高达482．1U／mL，最适反应pH值为4．8，最适反应温度为65℃；乙醇体积分数为10％时对酶活有最大促进效果，乙醇耐受能力高达30％；将该酶应用于同步糖化发酵研究中，发现发酵至120h乙醇质量浓度可高达41．25g/L，与对照相比，乙醇产量均提高近2倍。该菌株所产的B一葡萄糖苷酶较高的酶活力、耐热性能、乙醇耐受性和同步糖化发酵促进效果，预示着该菌在纤维素乙醇产业化应用中具有广阔的应用前景