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1 IntroductionThestickingpointofassociationrulealgorithmsdependsoneffectivelyfindingallcorrelationpatternsthatsatisfyvaluerequirementinthemagnanimityofdata.Butthealgorithmsalsobringanegativeef fect:thenumberofassociationrulesisverylarge.Alsoinformation… 相似文献
3.
The Research of ST-OFDM in Physical Layer of IEEE 802.16a 总被引:1,自引:0,他引:1
JU Mei-yan ZHU Qi FENG Guang-zeng Department of Communication Engineering Nanjing University of Posts Telecommunications Nanjing P.R.China 《中国邮电高校学报(英文版)》2004,11(4)
This paper briefly introduces one of the three physical layer implementations of IEEE 802.16a~[1],WirelessMAN-OFDM PHY.Based on the implementation,the combination of Orthogonal Frequency Division Multiplexing(OFDM)and Space-Time Coding(STC)which is briefly called ST-OFDM in IEEE 802.16a,is investigated under thechannel provided in Ref.[2].Especially,this paper is focused on the influence of the optimal decision threshold on the sys-tern Bit-Error-Rate(BER)performance based on unequal probabilities of sources.The simulations show that when Signal-Noise-Ratio(SNR)is low the optimal decision threshold is obviously superior to the usual one;when SNR is high to someextent,such as 10 dB for 4QAM and 16 dB for 16QAM,we can use the usual decision threshold instead of the optimal 相似文献
4.
Ian Turk Matthew Sin Xin''an Zhou Jun Tao Chaoli Wang Qi Liao 《International Journal of Software and Informatics》2016,10(3)
We present a visual analytics system to understand the operation data of a
company, GAStech, from IEEE VAST Challenge 2016. The data include proximity data
recording the locations and movements of employees, and heating, ventilation, and air
conditioning (HVAC) data recording the environmental conditions in the building.
Analyzing the data to detect the suspicious behaviors of some disgruntled employees is of
special interest. Our system provides coordinated multiple views to visualize the proximity
data and the HVAC data over time. Visual hints and comparisons are designed for users to
identify abnormal patterns and compare them. Furthermore, the system automatically
detects and correlates the anomalies in the data. We provide use cases to demonstrate the
effectiveness of our system. 相似文献
5.
提出一个传送未知团簇态的方案.在这个方案中,传送者利用一个非最大的三粒子纠缠态和一个非最大的四粒子纠缠态作为量子通道,当接收者执行适当的幺正操作时,可以以一定的概率完成未知团簇态的量子隐形传送. 相似文献
6.
Hong Zhang) Xiao-gang Li) Cui-wei Du) Hui-bin Qi) ) School of Materials Science Engineering University of Science Technology Beijing Beijing China ) Institute of Welding Surface Technology Baoshan Iron & Steel Co. Ltd. Shanghai China 《北京科技大学学报(英文版)》2009,16(4):414-421
The corrosion behavior and mechanism of hot-dip galvanized steel and interstitial-free (IF) substrate with alkaline mud adhesion were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and linear polarization. The results show that non-uniform corrosion occurs on the galvanized steel and IF substrate during 250 h with the mud adhesion. The corrosion products on the galvanized steel are very loose and porous, which are mainly ZnO, Zn5(OH... 相似文献
7.
介绍建筑涂料水性化。从五十年代至今发展的必然性和存在的优势是显而易见。但其产品品种单一,质量不尽人意,其中存在一哄而上,技术实力不一等问题,而在我们涂料工业中却未能引起重视。建筑涂料水性化既为发展方向,必由我们涂料工业担当此任,为未来发展应发挥主力军作用。 相似文献
8.
An accurate chlorine bulk decay model is needed to ensure that potable water meets the microbial and the chemical safeties at the treatment plant and throughout the distribution. Among the mathematical models available,the general second-order chlorine bulk decay model( GBDM) is the most fundamentally sound.Application of the GBDM,however,has been hindered by its numerous fictive parameters and lack of an analytical solution. This theoretical work removes the two obstacles. The GBDM is solved through transformation and integration. The analytical solution provides deep insights into the GBDM and facilitates the parameterization and sensitivity analysis. The background natural organic matter( NOM) is characterized with the probabilistic distribution of functional groups. It reveals that the mean of the function group distribution is correlated with the initial chlorine decay rate coefficient( κ_0). A simple formula is developed to determine κ_0 directly from the initial chlorine decay. The theoretical treatment reduces the fictive parameters to a minimum. For the common lognormal distribution,the GBDM needs only three parameters,well defined as initial chlorine demand X_0,median rate coefficient km,and heterogeneity index σ. For more complicated scenarios,composite distributions are constructed through superposition of individual distributions. A highlighted example is to predict chlorine decay in blends of different waters. With the theoretical and mathematical advancement here,the GBDM can be applied effectively to any reactive background matter in any reaction systems. 相似文献
9.
To study the configuration and conductivity effects on micro?scale methane?air flames by electric field and iron wind, different electric field forces and iron winds are generated by needle, circle and... 相似文献
10.
Li Fang He Yedong Qi Huibin Huang Zhenzhong Zhu Rizhang Beijing Corrosion Protection Centre Open Laboratory of Corrosion Erosion Surface Technology University of Science Technology Beijing Beijing 《中国有色金属学会会刊》1997,(2)
FeMoAlCOATINGANDITSHIGHTEMPERATURESULFIDATIONPROPERTIES①LiFang,HeYedong,QiHuibin,HuangZhenzhong,ZhuRizhangBeijingCorosionand... 相似文献