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21.
当前小体积远端射频单元(Remote Radio Unit,RRU)主要是皮站级别的Pico-RRU,其重量和体积仍然难以满足掌上型的要求。为此,采用高集成度的AD9361芯片来实现长期演进(Long Term Evolution,LTE)宽带收发信机功能,配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点,成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm,质量约500 g,量产成本千元以内。测试表明,该RRU下行误差向量幅度(Error Vector Magnitude,EVM)小于3%,优于3GPP要求的8%;10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。 相似文献
22.
目的探讨纤维蛋白胶(FG)粘合法联合神经生长因子(NGF)治疗周围神经损伤的临床疗效。方法选取我院2006年8月至2013年10月就诊的124例腓总神经损伤患者,随机均分为两组,对照组患者单纯使用缝合法,试验组患者在缝合法的基础上配合使用FG粘合法联合NGF治疗,随访6个月以上,分析两组患者的运动功能和患肢感觉疗效。结果试验组患者总有效率明显优于对照组,差异有统计学异议(P<0.05)。结论周围神经损伤的修复与再生过程中使用FG粘合法联合NGF治疗,可有效改善患者症状,安全性高,不良反应较少。 相似文献
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Disclosure standards mandate the quantitative disclosure of hedging‐instrument‐related risks but not the disclosure of hedged‐item‐related risks. We examine how a match (mismatch) in formats, caused by making quantitative (qualitative) hedged item disclosures alongside quantitative hedging instrument disclosures, affects investors' integration of information from these two related disclosures. Our first experiment varies the hedged item disclosure format (quantitative or qualitative) and the portion of risk hedged (small or large). We find that when disclosure formats are mismatched, the less comparable nature of the two disclosures caused investors to neglect the offsetting relationship when assessing net risks. As a result, risk and investment judgments were influenced by the more prominent quantitative hedging instrument disclosures. Our second experiment finds that the use of a qualitative debiaser that clarifies the relationship between the two disclosures led to the integration of information and mitigated this effect. 相似文献
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Drawing on the work–family enrichment theory, the present study investigates the cross-domain effects of ethical leadership on employees’ family and life satisfaction. Moreover, it focuses on the mediating role of work–family enrichment (WFE) and the moderated mediation process of family-supportive supervisor behaviors (FSSB) underlying the relationship between ethical leadership and employees’ family and life satisfaction. Using a sample of 371 employees and their immediate supervisors in China, we found that WFE mediated the relationship between ethical leadership and employee-rated and supervisor-rated family and life satisfaction. Moreover, FSSB positively moderated the relationship between ethical leadership and WFE, such that the relationship was strengthened when FSSB were higher. Furthermore, the mediations of WFE between ethical leadership and employee-rated and supervisor-rated family and life satisfaction were also positively moderated by FSSB, such that the indirect effects were stronger when FSSB were higher. The theoretical and managerial implications of our findings are further discussed. 相似文献
26.
张燕 《内蒙古财经学院学报(综合版)》2006,4(1)
面对浩如烟海的网络信息资源丰富又无序、新颖又形象、急需开发利用。本文探讨了开发利用网上信息资源的必要性,介绍了如何开发利用网上信息资源,为用户充当网络信息导航员,发掘网上信息,丰富现有信息源等几种方法。 相似文献
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This paper analyzes the issue costs and initial pricing of bonds in the international market. In particular, we investigate the determinants of three components of issue costs: underwriter fee, underwriter spread (the difference between the offering price and the guaranteed price to the issuer), and underpricing (the difference between the market price and the offering price). Total underwriter compensation increases with the bonds' credit risk and maturity, but it is insignificantly related to issue size. Interestingly, underwriters appear to price some issue characteristics directly (by adjusting the fee) and other characteristics indirectly (by setting the guaranteed price). The two compensation components (fee and spread) are negatively related to each other. We provide evidence that this trade-off is consistent with income tax considerations, as well as with two-tier pricing by underwriters. We find no evidence of underpricing. 相似文献
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