Activity recognition and intensity estimation in youth from accelerometer data aided by machine learning

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.     

Accelerated Manhattan hashing via bit-remapping with location information

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...     

资源受限网络中高效XML交换的性能评估

为了研究高效XML交换(EXI)在资源受限网络中的使用情况,文中基于传感器观测服务的真实数据,对四种交换模式下的数据大小进行了对比:XML、高效XML、Gzip压缩的XML以及开启压缩模式的高效XML。通过在ns-2中建模,对资源受限网络环境下各交换格式的平均成功率、平均延时、平均能量消耗等性能进行了分析。实验结果表明,无论是否开启压缩模式,高效XML比XML具有更小的体积、更高的成功率、更短的延时和更少的能量消耗。高效XML交换更加适合于资源受限网络。     

RFID触控屏幕点餐系统

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]。     

Real time 3D simulation for nose surgery and automatic individual prosthesis design

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.     

模糊系统逼近理论：现状与展望

近年来,各类模糊系统已被证明是万能函数逼 近器,它们能实现任意的非线性连续控制规律和动态模型．本文综述与分析了模糊系统逼近 理论研究的最新成果,并指出了进一步研究工作的方向．     

论室内色彩设计的人性化

人性化的色彩设计理念体现出对使用者的人文精神关怀。本文从色彩的基本特征出发,对室内设计色彩人性化问题加以探讨。以理论和实际相结合的论述手法,探索室内环境人性化色彩设计的方法。人性化是未来室内环境色彩设计的必然趋势。     

A Fast Search Algorithm for a Large Fuzzy Database

In this paper, we propose a fast search algorithm for a large fuzzy database that stores iris codes or data with a similar binary structure. The fuzzy nature of iris codes and their high dimensionality render many modern search algorithms, mainly relying on sorting and hashing, inadequate. The algorithm that is used in all current public deployments of iris recognition is based on a brute force exhaustive search through a database of iris codes, looking for a match that is close enough. Our new technique, Beacon Guided Search (BGS), tackles this problem by dispersing a multitude of ldquobeaconsrdquo in the search space. Despite random bit errors, iris codes from the same eye are more likely to collide with the same beacons than those from different eyes. By counting the number of collisions, BGS shrinks the search range dramatically with a negligible loss of precision. We evaluate this technique using 632,500 iris codes enrolled in the United Arab Emirates (UAE) border control system, showing a substantial improvement in search speed with a negligible loss of accuracy. In addition, we demonstrate that the empirical results match theoretical predictions.