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191.
提出了一种基于虚拟实时服务的协议构架,可有效发掘用户提出通信请求之前的“负时间轴”上的空闲时频资源或可再生能源,将用户可能感兴趣的内容以多播的方式预先推送到终端的存储器中,从而以非实时的通信提供虚拟实时服务,在确保服务质量的前提下大幅度提升频谱和能量效率.对终端缓存内容的选择算法进行了标准化,从而允许基站在本地预测用户已缓存的内容,并判断当前是否应发起推送和推送哪条内容;提出了虚拟实时服务涉及的若干关键算法,也给出了虚拟实时服务的演进途径及主要开放问题,旨在为相关新兴产业的技术发展提供参考.  相似文献   
192.
随着电信行业4G通信网络技术的普及,移动端互联网应用正蓬勃发展,随之带来的数据流量呈爆炸式增长,传统的处理方法难以支撑海量信令数据的实时查询需求,为此,提出了一种基于Hadoop的大数据实时查询平台,以支撑超大规模的信令详单的处理.通过数据采集、数据建模、rowkey设计、数据入库、二级索引、数据压缩与存储等实现方法,提供了实时数据查询服务.最后,在现网实验环境进行了验证,能够取得非常好的收益.  相似文献   
193.
结合移动公司内部相关制度,对质量检测过程中产生的损耗进行了流程设计,提出了改造ERP系统,在ERP系统中增加损耗检测出库项目,同时进一步提出对损耗物资进行修复的理念,并明确了损耗产品的修复处理流程,最大限度地减少检测损耗对公司带来的损失,同时完善了相关规章制度,为质量检测工作提供了制度依据。  相似文献   
194.
195.
从教学内容、教学方法、实验实践环节、考核方式等角度,深入分析了《聚合物成型加工》课程的教学现状,并在此基础上指出,目前单纯的理论教学与人才培养目标相悖,缺乏系统性的实验实践教学体系和多样化的课程考核方式。《聚合物成型加工》实践教学体系改革本着培养应用型人才的原则,从实际生产问题和研发前沿问题入手,由原来单纯的课堂教学模式改为课堂教学与实践环节相结合;考核也改为"书面作业+调研报告+项目答辩+实践操作+考试"的综合考核形式;并设计了系统性的创新实践环节,使学生在掌握课程所学基础知识的同时,可以独立的根据制品性能和使用要求,进行合理的聚合物成型物料配制,选择合适的成型加工方法,利用实验室及产学研实践基地的加工条件自己动手将聚合物原材料做成制品。  相似文献   
196.
Resveratrol is a polyphenol that has numerous interesting biological properties, but, per os, it is quickly metabolized. Some of its metabolites are more concentrated than resveratrol, may have greater biological activities, and may act as a kind of store for resveratrol. Thus, to understand the biological impact of resveratrol on a physiological system, it is crucial to simultaneously analyze resveratrol and its metabolites in plasma. This study presents an analytical method based on UHPLC-Q-TOF mass spectrometry for the quantification of resveratrol and of its most common hydrophilic metabolites. The use of 13C- and D-labeled standards specific to each molecule led to a linear calibration curve on a larger concentration range than described previously. The use of high resolution mass spectrometry in the full scan mode enabled simultaneous identification and quantification of some hydrophilic metabolites not previously described in mice. In addition, UHPLC separation, allowing run times lower than 10 min, can be used in studies that requiring analysis of many samples.  相似文献   
197.
A new discrimination method, called hit quality index (HQI)-voting, that uses the HQI for discriminant analysis has been developed. HQI indicates the degree of spectral matching between two spectra as known. In this method, a library sample yielding the highest HQI value for an unknown sample was initially searched and a group containing this sample was chosen as the group for the unknown sample. When overall spectral features of two groups are quite close to each other, many library samples with similar HQI values could be available for an unknown sample. In this situation, the simultaneous consideration of multiple votes (several library samples with close HQI values) for final decision would be more robust. In order to evaluate the discrimination performance of HQI-voting, three different near-infrared (NIR) spectroscopic datasets composed of two sample groups were used: (1) domestic and imported sesame samples, (2) domestic and imported Angelica gigas samples, and (3) diesel and light gas oil (LGO) samples. For the purpose of comparison, principal component analysis–linear discriminant analysis (PCA–LDA), partial least squares–discriminant analysis (PLS–DA) as well as k-nearest neighbor (k-NN) were also performed using the same datasets and the resulting accuracies were compared. The discrimination performances improved with the use of HQI-voting in comparison with those resulted from PCA–LDA and PLS–DA. The overall results support that HQI-voting is a comparable discrimination method to that of existing factor-based multivariate methods.  相似文献   
198.
In this article, we obtained equations that permit us to calculate the hydrophilic-lipophilic balance (HLB) value of polyoxyethylene esters from quality control data of the raw materials (fatty acids and polyethylene glycol) and the finished product (surfactant). These data include the acid value of the fatty acid, the hydroxyl value of the polyethylene glycol, and the hydroxyl value of the surfactant. These calculations permit us, moreover, to know the mean molecular masses of fatty acids, of polyethylene glycol, of monoester and diester, and the proportion of polyoxyethylene monoester and polyoxyethylene diester.  相似文献   
199.
Theory regarding emulsification, its coalescence and impact of emulsifier over its stability has been updated. For the verification of the proposed theory, water-in-oil emulsion was prepared by mixing water and soybean oil in the presence and absence of emulsifier, monoglyceride. The effect of different parameters like emulsification time, contents of water, and concentration of emulsifier has been investigated on the emulsification and coalescence process of the emulsion. It was noted that the emulsion quality was highest if the mixture was homogenized for about 15 minutes and the water contents were 40% v/v. The addition of monoglyceride up to 0.5% w/v gave the most stable emulsion having higher quality than other composition. The results obtained were compared with the proposed theory and found to have good compositions.   相似文献   
200.
Abstract

Two exercises (MEDCAL I and II) were conducted in our Department during November 1984 and October 1986, with participants from the Mediterranean region, for testing the IOC Manual for the determination of petroleum hydrocarbons in sediments (IOC, Manuals and Guides, No. 11).

The gas chromatographic analysis of the saturated hydrocarbon fraction provided, at the best, a precision of 60% (relative standard deviation RSD) for n-alkanes (mean conc. 0.89 μg/g) and 56 % for the unresolved complex mixture (UCM) (mean conc. 16μg/g). The CPI and the pristane/phytane ratio provided better results (13% RSD). The aromatic fractions, analysed by UV-fluorescence, yielded in total a mean concentration of 10μg/g of chrysene equivalents with a 49% RSD.

The extraction-partition step was confirmed to be the main source of error in the analysis because when the results were corrected for recoveries, the RSD were reduced to 17, 30 and 6% for n-alkanes, UCM and total aromatics, respectively. Our reference intra-laboratory precision was, respectively, 18, 14 and 14%.  相似文献   
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