Ensemble learning HMM for motion recognition and retrieval by Isomap dimension reduction

INTRODUCTION Now more and more motion capture systems are used to acquire realistic human motion data. Due to the success of the Mocap systems, realistic and highly detailed motion clips are commercially available and widely used for producing animations of human-like characters in a variety of applications, such as simu- lations, video games and animation files. Therefore an efficient motion data recognition and retrieval technique is needed to support motion data processing, such as mot…     

The effect of concept cartoon-embedded worksheets on grade 9 students’ conceptual understanding of Newton’s Laws of Motion

Background: A substantial review study of concept cartoons reports that few studies have indicated their functions. For this reason, the present study illuminates the extent to which concept cartoon-embedded worksheets (through constructivist context) accomplish these functions in conceptual learning.

Purpose: The purpose of the study is to determine the effect of the concept cartoon-embedded worksheets on grade 9 students’ conceptual understanding of Newton’s Laws of Motion.

Sample: Within a quasi-experimental research design with control group, the sample consisted of 102 grade 9 students (aged 15–16 years) enrolled in an Anatolian High School. They were randomly assigned to control (52 students) and experimental groups (50 students).

Design and methods: While the control group followed the existing physics instruction, the experimental one was exposed to the concept cartoon-embedded worksheets. To collect data, two scales (Newton’s Laws of Motion Test –NLMT– and Interview about Instances –IAI) were employed.

Results: The results indicated that the experimental group performed better than did the control group.

Conclusions: It can be deduced that the concept cartoon-embedded worksheets are effective in improving grade 9 students’ conceptual understanding and in replacing their alternative conceptions with scientific ones.     

H．264/AVC中快速运动估计算法研究

运动估计是H.264中关键技术之一。全搜索(FS)虽然能得到最佳的匹配,但在计算上却很繁琐,难以达到实时的要求。对EPZS、UMHexagonS和简化UMHS快速运动估计算法进行了分析。通过与FS的实验比较,归纳出EPZS、UMHexagonS和简化UMHS算法各自的优势。     

全球社群 云端学习——第16届全球华人计算机教育应用大会(GCCCE2012)综述

第16届全球华人计算机教育应用大会(GCCCE2012)由台南大学数字学习科技学系主办,于2012年5月28日至6月1日在台湾屏东县恒春垦丁福华饭店举行。大会以"全球社群、云端学习"为主题,期盼能够协同全球华人的数字学习研究,携手迈向新纪元。本次大会有来自美国、德国、墨西哥、新加坡、马来西亚、日本以及中国大陆、台湾、香港、澳门地区等地的学者及教师300多人参加。与会者就计算机辅助合作学习、人工智能教育应用、数字化教室、行动与无所不在学习、悦趣化学习与社会、科技于高等教育与人力绩效之应用、科技增强语言学习、政策及学习评估、数字科技、创新与教育等研究议题,以论文发表、教师论坛、博士生论坛与工作坊等形式进行了学术交流,为教育技术进一步发展提供新的机遇及挑战。     

抑制低速部件爬行的研究

八十年代的航空、航天以及超大规模集成电路等尖端技术之能够成为现实,无不与超精密加工发生紧密的联系。现代超高精度加工技术的开发目标是毫微米加工,即实现紫外线波长到X光波长(10~(-9)m)的加工精度。但机床运动部件在低速移动时会出现爬行现象,如何抑制爬行?本文通过大量的试验对爬行机理进行研究并提出一种用法向激振来抑制爬行的办法。实验结果表明是可行的,引起同行专家的注目。     

A complexity-scalable software-based MPEG-2 video encoder

INTRODUCTION processors and digital signal processors (DSP), video encoding on these processors without hard- Digital video compression techniques have ware assistance may be an alternative with advan-played an important role in the field of telecom- tages of short development cycles, easy upgrademunication and multimedia systems where band- and low cost. Video coding consumes much com-width and storage resources are limited. The prime putation time, and so, is a problem for real-timeimp…     

Multi-user Motion JPEG2000 over wireless LAN: run-time performance-energy optimization with application-aware cross-layer scheduling

This paper introduces a video application-aware cross-layer framework for joint performance-energy optimization, considering the scenario of multiple users upstreaming real-time Motion JPEG2000 video streams to the access point of a WiFi wireless local area network and extends the PHY-MAC run-time cross-layer scheduling strategy that we introduced in (Mang-haram et al., 2005; Pollin el al., 2005) to also consider congested network situations where video packets have to be dropped. We show that an optimal solution at PHY-MAC level can be highly suboptimal at application level, and then show that making the cross-layer framework application-aware through a prioritized dropping policy capitalizing on the inherent scalability of Motion JPEG2000 video streams leads to drastic average video quality improvements and inter-user quality variation reductions of as much as 10 dB PSNR, without affecting the overall energy consumption requirements.     

The validity and intra-tester reliability of markerless motion capture to analyse kinematics of the BMX Supercross gate start

The aim of this study was to quantify the validity and intra-tester reliability of a novel method of kinematic measurement. The measurement target was the joint angles of an athlete performing a BMX Supercross (SX) gate start action through the first 1.2 s of movement in situ on a BMX SX ramp using a standard gate start procedure. The method employed GoPro® Hero 4 Silver (GoPro Inc., USA) cameras capturing data at 120 fps 720 p on a ‘normal’ lens setting. Kinovea 0.8.15 (Kinovea.org, France) was used for analysis. Tracking data was exported and angles computed in Matlab (Mathworks®, USA). The gold standard 3D method for joint angle measurement could not safely be employed in this environment, so a rigid angle was used. Validity was measured to be within 2°. Intra-tester reliability was measured by the same tester performing the analysis twice with an average of 55 days between analyses. Intra-tester reliability was high, with an absolute error <6° and <9 frames (0.075 s) across all angles and time points for key positions, respectively. The methodology is valid within 2° and reliable within 6° for the calculation of joint angles in the first ~1.25 s.     

A constrained linear quadratic optimization algorithm toward jerk-decoupling cartridge design

Linear direct feed drives are widely used in machine tools, but an abrupt counter force from the secondary part will induce the jerk to the metro frame contacted with the linear motor and cause the vibration of auxiliary devices on it. The jerk-decoupling cartridge (JDC) provides a buffer to reduce such an impact. Design target for such a system includes both the tracking error and the jerk induced to the metro frame. To achieve both targets systematically, this work presents an integrated approach to efficiently determine parameters in the JDC and the position controller of the feed drive. The problem is firstly formulated as a nonlinear constrained optimization problem, which is then converted to a series of projection gradient optimization problems and step searching problems, which are either convex or linear. Thus, fast convergence of parameters are achieved within first several iterations. Through a series of simulation, the effectiveness of proposed methodology is verified.