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91.
Statistical analysis of the decision threshold for parallel PN code acquisition in a Rician fading channel is presented. It is shown that in the performance analysis of the acquisition system with reference filtering, the statistical evaluation of the decision threshold seems more appropriate than the approximation of the decision threshold  相似文献   
92.
钢铁表面锌系磷化膜的研究   总被引:3,自引:0,他引:3  
本文采用SEM和TEM等测试手段,研究了四功能处理液不同条件下在钢铁表面上形成锌系磷化膜的形貌,晶体结构;采用EDS研究了磷化膜的化学成发,通过实验确定了Zn/P值在2.12~3.20时,磷化膜具有良好的耐蚀性。  相似文献   
93.
Rotavirus (RV) strains infecting newborns often have unique neutralization antigens (P serotypes) on their outer capsids that are distinct from those found on RV strains that cause diarrhea in older children. We examined the hypothesis that unusual RV strains preferentially infect newborns because the newborns lack maternal neutralizing antibodies to these strains. To test this hypothesis, sera and saliva samples collected from neonates infected with 116E-like (P[11]G9) strains in the maternity ward of the All India Institute of Medical Sciences (AIIMS) hospital in New Delhi were tested for neutralizing antibodies against common RV strains and those infecting newborns and these titers were compared with those of newborns who did not become infected (controls). The infected neonates had significantly lower levels of cord blood neutralizing antibodies to 116E than the controls, suggesting that immunity to neonatal RV infection is acquired transplacentally through maternal antibodies. Further, this study confirmed the immunogenicity of the AIIMS neonatal strain 116E, a vaccine candidate, in its ability to evoke a potent RV-specific immunoglobulin A and neutralizing antibody response in serum and saliva among the infected babies. Our findings have important implications for the development of an effective RV vaccine. In India, where G9 strains are common in the community, the use of 116E as a vaccine, together with the rhesus tetravalent vaccine, may provide a broader protection against all the circulating RV serotypes, including serotype G9, which is not represented in the current rhesus RV tetravalent vaccine (G1-G4).  相似文献   
94.
Pre-bainitic Transformation in Fe-Ni Alloy   总被引:1,自引:0,他引:1  
Thepre-bainiticphenomenonisoneoftheim-portantsubjectsofbainitictransformationwhichisstilcontroversial.Oneviewisthatthesolutea...  相似文献   
95.
随着招投标过程信息化的快速发展,越来越多的招标、评标、中标信息统一集中在相应交易中心平台网站上进行公示,使采用大数据手段分析建设工程信息成为了可能。采用Web Scraper插件爬取网页内容简便、高效、准确。大数据的介入能很大程度遏制非法围标、串标行为,保证公共资源交易过程的公平、公正,有效打击权力寻租。同时大数据分析以定量、可视化的成果展示了建设工程的市场行为趋势,为政府的宏观调控提供更精确的数据性指导性意见。  相似文献   
96.
Koo  Bonhun  Jeon  Hyunsik  Kang  U. 《Knowledge and Information Systems》2021,63(12):3139-3158
Knowledge and Information Systems - Given sequential news watch logs of users, how can we accurately recommend news articles? Compared to other items (e.g., movies and e-commerce products) for a...  相似文献   
97.
The Journal of Supercomputing - Direct numerical simulations (DNS) of turbulent flows have increasing importance because they not only provide fundamental understanding of turbulent flows but also...  相似文献   
98.
以TI公司的MSP430F5438单片机为控制核心,结合步进电机和精密电位器WDD35D-4,实现了基于自由摆的平板控制与激光追踪系统。当摆杆摆角为45°~60°时,平板可以承载8枚一元硬币,并在5个摆动周期内维持稳定;当摆杆摆角为30°~60°时,固定在摆杆平板上的激光笔可以在15s内找到并跟踪1.5m远处的靶心。  相似文献   
99.
Graphs appear in numerous applications including cyber security, the Internet, social networks, protein networks, recommendation systems, citation networks, and many more. Graphs with millions or even billions of nodes and edges are common-place. How to store such large graphs efficiently? What are the core operations/queries on those graph? How to answer the graph queries quickly? We propose Gbase, an efficient analysis platform for large graphs. The key novelties lie in (1) our storage and compression scheme for a parallel, distributed settings and (2) the carefully chosen graph operations and their efficient implementations. We designed and implemented an instance of Gbase using Mapreduce/Hadoop. Gbase provides a parallel indexing mechanism for graph operations that both saves storage space, as well as accelerates query responses. We run numerous experiments on real and synthetic graphs, spanning billions of nodes and edges, and we show that our proposed Gbase is indeed fast, scalable, and nimble, with significant savings in space and time.  相似文献   
100.
Due to the explosive increases of data from both the cyber and physical worlds, the demand for database support in embedded systems is increasing. Databases for embedded systems, or embedded databases, are expected to provide timely in situ data services under various resource constraints, such as limited energy. However, traditional buffer cache management schemes, in which the primary goal is to minimize the number of I/O operations, is problematic since they do not consider the constraints of modern embedded devices such as limited energy and distinctive underlying storage. In particular, due to asymmetric read/write characteristics of flash memory-based storage of modern embedded devices, minimum buffer cache misses neither coincide with minimum power consumption nor minimum I/O deadline misses. In this paper we propose a novel power- and time-aware buffer cache management scheme for embedded databases. A novel multi-dimensional feedback control architecture is proposed and the characteristics of underlying storage of modern embedded devices is exploited for the simultaneous support of the desired I/O power consumption and the I/O deadline miss ratio. We have shown through an extensive simulation that our approach satisfies both power and timing requirements in I/O operations under a variety of workloads while consuming significantly smaller buffer space than baseline approaches.  相似文献   
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