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61.
Physical activity monitoring for youth is an area of increasing scientific and public health interest due to the high prevalence of obesity and downward trend in physical activity. However, accurate assessment of such activity remains a challenging problem because of the complex nature in which certain activities are performed. In this study, we formulated the issue as a machine learning problem—using a diverse set of 19 physical activities commonly performed by youth—via two approaches: activity recognition and intensity estimation. With the aid of training data, we implemented a distance metric learning method called DML-KNN that utilizes time-frequency features and is capable of effectively classifying both continuous and intermittent movement in youth subjects. Four different time-frequency feature extraction methods were then systematically evaluated. Our results show that the DML-KNN method performed competitively, especially when using features extracted by the Tamura method for intensity estimation, and by the Square Coefficient method for activity recognition. 相似文献
62.
Chen Wenshuo Ding Guiguang Lin Zijia Pei Jisheng 《Multimedia Tools and Applications》2017,76(2):2441-2466
Multimedia Tools and Applications - Hashing is a binary-code encoding method which tries to preserve the neighborhood structures in the original feature space, in order to realize efficient... 相似文献
63.
餐饮行业的传统书面方式及定点式系统点餐服务方式已经不能满足人们生活水平日益提高的需求。结合RFID卡及卡片阅读机,利用Visual Basic作为前台开发工具,以Socket建立TCP联机并以此来传输数据,利用Access建立后台数据库开发并完成了RFID触控屏幕点餐系统[1]。 相似文献
64.
Wang JX Liao SH Zhu XH Wang Y Ling CX Ding X Fang YM Zhang XH 《Computer methods and programs in biomedicine》2011,104(3):472-479
This paper presents an intuitive nose surgery planning and simulation system, using 3D laser scan image and lateral X-ray image, to provide high quality prediction of the postoperative appearance, and design the patient specific prosthesis model automatically. After initial registration, the internal surface of soft tissue at the nose region was generated by the statistical data for soft tissue thickness adapted by the individual thickness information from the X-ray image. Then, the sketch contour of the 3D scan data on the lateral X-ray image was modified manually or adjusted automatically according to some aesthetic statistical data, to drive the simulation in real time by the state-of-the-art Laplacian surface deformation method. When satisfied with the 3D postoperative appearance, the deformation was mapped to the internal surface of soft tissue, and the change before and after simulation was utilized to generate the patient specific prosthesis model automatically. The surgeons who used the system confirmed that this planning system is attractive and has potential for daily clinical practice. 相似文献
65.
An interactive three-dimensional finite element generation method is presented for modelling a multi-connected teeth and mandible structure. The tetrahedron is chosen as the basic element type due to its rigorous adaptability to structures with geometric complexities. The mesh generation is implemented by allocating two quadrangles in adjacent CT image slices to form a set of tetrahedrons. By examining all the possible allocations and their degradations, an algorithm is developed for interactive mesh generation, resulting in a series of tetrahedrons consistent with all the others without overlapping and spacing. The developed system was applied to a tooth-mandibular structure, generating a complicated 3D FEM model consisting of 4762 nodes and 18,534 tetrahedral elements with nine different materials. This 3D model was successfully used to evaluate different tooth restoration strategies, which proved the viability and effectiveness of the proposed method. 相似文献
66.
面向企业的运输销售管理信息系统设计 总被引:3,自引:0,他引:3
以石油企业运输销售经营管理为背景,对运输销售管理信息系统进行了研究.以软件工程为指导,运用先进的设计方法与结构分析,并结合数据库的特点给出了运输销售管理信息系统具体的设计方案. 相似文献
67.
请求式拨号网络还存在着冗余很大的网络传输和拨号连接,为减少电信成本,文章尝试对Windows NT请求式拨号网络进行优化。 相似文献
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70.
在含有0.3mol.L~(-1)HAC-NH_4AC(pH=5.8)和2.0×10~5mol.L~(-1)PV 溶液中,可得到铟(Ⅱ)-PV 配合物极谱波。峰电位在-0.69V(VS.SCE)处,其导数峰高与铟(Ⅲ)在0.020~0.400mg.L~(-1)范围内的浓度有良好的线性关系,最低检出限为0.005mg.L~(-1)。研究了该波的机理,证明是一种配合吸附波,并应用于轴承镀层中铟含量的测定。 相似文献