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991.
《Journal of Location Based Services》2013,7(4):272-290
Global positioning systems (GPS) logs recorded in personal devices contain rich information such as travel patterns, locations of frequent visits and place–event associations. There have been rather successful attempts in detecting the mode of transport from GPS logs such as walking, driving or taking a bus, which has found varied applications. However, the best-known schemes either require tedious manual labelling or pre-training process (or both). We present MoDetect (MD), a unsupervised scheme which eliminates the need of manual labelling and pre-training while attaining equal or greater accuracy compared with the best-known supervised methods. MD can also cater for differences in individual's behaviours, and hence may be more widely applicable than the existing schemes. To achieve this, MD relies on Kolmogorov–Smirnov test which offers a theoretical assurance when computing similarity between segments of records. Our analysis shows that the higher speed modes can be better differentiated through a weighted bootstrapping procedure. We also augment the decisions with reference to the transfer probabilities between different modes at locations identified from the GPS records. 相似文献
992.
刘光兰 《青岛大学学报(工程技术版)》2000,15(4):90-91
通过数学分析得出振动质点的速度与强迫之间的相位差。正是有这一相位差,才使强迫力对振动系统所做的功正好抵消阻尼对振动系统所做的负功,以保证稳定振动的等幅性。 相似文献
993.
结合油气进入钻井液方式对各种气显示形成原因及其在气测录井图上所表现的特征进行探讨。分析了钻井气、停钻气、再循环气、起下钻气、方钻杆气、污染气、CaC2气七敢显示的成因及其特征,特别注意钻进气同其它气显示叠加在一起的显示。气显示类型具有多要性,其形成原因是多方面的。掌握气显示形成原因和其在录井轷 的特征是对储层做出正确评价的先决条件。 相似文献
994.
Image Registration Using Wavelet-Based Motion Model 总被引:2,自引:0,他引:2
Yu-Te Wu Takeo Kanade Ching-Chung Li Jeffrey Cohn 《International Journal of Computer Vision》2000,38(2):129-152
An image registration algorithm is developed to estimate dense motion vectors between two images using the coarse-to-fine wavelet-based motion model. This motion model is described by a linear combination of hierarchical basis functions proposed by Cai and Wang (SIAM Numer. Anal., 33(3):937–970, 1996). The coarser-scale basis function has larger support while the finer-scale basis function has smaller support. With these variable supports in full resolution, the basis functions serve as large-to-small windows so that the global and local information can be incorporated concurrently for image matching, especially for recovering motion vectors containing large displacements. To evaluate the accuracy of the wavelet-based method, two sets of test images were experimented using both the wavelet-based method and a leading pyramid spline-based method by Szeliski et al. (International Journal of Computer Vision, 22(3):199–218, 1996). One set of test images, taken from Barron et al. (International Journal of Computer Vision, 12:43–77, 1994), contains small displacements. The other set exhibits low texture or spatial aliasing after image blurring and contains large displacements. The experimental results showed that our wavelet-based method produced better motion estimates with error distributions having a smaller mean and smaller standard deviation. 相似文献
995.
When we consider the numerical solution of the 2-dimensional linear hyperbolic problem by implicit difference equations we need to solve a set of linear systems Ax = b with many rightband sides b, where A is large, sparse and nonsymmetric. The SUR (Successive Underrelaxation) and GCG (Generalised Conjugate Gradient) methods are used for solving the linear systems. We compare the two methods on sequential and parallel computations. Numerical results indicate that the SUR method is nearly twice as fast as the GCG method and the SUR method has an almost linear speedup. 相似文献
996.
西澳SINO铁矿选矿厂的设计理念和方式与国内同类项目存在较大差异,本文从总图运输专业的角度对设计标准、专业设置、图纸要求及设计中应注意的问题进行阐述。 相似文献
997.
Reference values of the chronoamperometric response at cylindrical and capped cylindrical electrodes
This work provides accurate solutions of the cylinder flux function I(0,1;T), first solved by Jaeger and Clarke, which can serve as reference values for electrochemical amperometric diffusion limited currents at a cylinder, as well as heat fluxes under equivalent conditions (fixed temperature at the cylinder surface). For the capped cylinder of varying lengths, reference values of time-dependent electrochemical currents are provided. Steady state currents at capped cylinders are presented and a function is provided that fits the simulated values to within 1%. All of these are more accurate than in previous works. 相似文献
998.
利用泛克里格方法消除MT噪音 总被引:2,自引:1,他引:1
对大地电磁测深(MT)资料,计算其变差函数;对这些变差函数进行回归分析,求得理论模拟变差函数;然后用泛克里格法估计大地电磁场信号,达到消除电磁场信号噪音的目的。通过实际资料的应用,效果比较理想。 相似文献
999.
在长沙第二长途电信枢纽工程3m厚混凝土基础底板的施工过程中,通过运用设置底板滑动层、表面抗裂钢筋、混凝土内部温度钢筋、混凝土材料及配合比的选用、降低混凝土入模温度、保温、保湿、养护等一系列技术措施,保证了该工程3m厚混凝土底板一次连续浇筑平仓到顶的施工质量。 相似文献
1000.
Yongqiang Sun Kai H. Lim Chunping Jiang Jerry Zeyu Peng Xiaojian Chen 《Computers in human behavior》2010
Informativeness and entertainment are regarded as two types of advertising value that can influence consumers’ attitudes toward Web advertising. Despite of many studies on these two factors, there are two research gaps in extant literature. First, the effects of informativeness and entertainment on attitude are considered separately, yet their interaction effect is neglected. Second, the role of individual characteristics (e.g., gender) in the advertising evaluation process is far from clear. To address these two issues, a laboratory experiment was conducted to investigate the interaction effect between informativeness and entertainment, and also the moderating role of gender. The results indicate that informativeness can help form a more positive attitude for males than for females, and entertainment can lead to a more positive attitude for females than for males. It is also found that there is a three-way interaction among informativeness, entertainment, and gender. More specifically, the interaction effect between informativeness and entertainment is significant for females, but insignificant for males. Results, research contributions, and limitations are discussed, and implications for future studies are suggested. 相似文献