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IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing
null
《医学前沿（英文）》 2013年 第7卷 第1期 页码 126-131 doi: 10.1007/s11684-012-0236-0
Recent evidence demonstrates the independent negative effects of sedentary behavior on health, but there are few objective measures of sedentary behavior. Most instruments measure physical activity and are not validated as measures of sedentary behavior. The purpose of this study was to evaluate the validity of the IDEEA system’s measures of sedentary and low-intensity physical activities: lying, reclining, sitting and standing. Thirty subjects, 14 men and 16 women, aged 23 to 77 years, body mass index (BMI) between 18 to 34 kg/m2, participated in the study. IDEEA measures were compared to direct observation for 27 activities: 10 lying in bed, 3 lying on a sofa, 1 reclining in a lawn chair, 10 sitting and 3 standing. Two measures are reported, the percentage of activities accurately identified and the percentage of monitored time that was accurately labeled by the IDEEA system for all subjects. A total of 91.6% of all observed activities were accurately identified and 92.4% of the total monitored time was accurately labeled. The IDEEA system did not accurately differentiate between lying and reclining so the two activities were combined for calculating accuracy. Using this approach the IDEEA system accurately identified 96% of sitting activities for a total of 97% of the monitored sitting time, 99% and 99% for standing, 87% and 88% for lying in bed, 87% and 88% for lying on the sofa, and 83% and 83% for reclining on a lawn chair. We conclude that the IDEEA system accurately recognizes sitting and standing positions, but it is less accurate in identifying lying and reclining positions. We recommend combining the lying and reclining activities to improve accuracy. The IDEEA system enables researchers to monitor lying, reclining, sitting and standing with a reasonable level of accuracy and has the potential to advance the science of sedentary behaviors and low-intensity physical activities.
李伯衡
《中国工程科学》 2007年 第9卷 第3期 页码 1-5
编制土地利用总体规划是为全面建设小康社会提供用地保障，是国务院强化宏观调控的重要举措。 为了提高土地利用总体规划的科学性和实用性，从理论上论述了推进土地利用总体规划的三大动力——粮食安 全生产，经济稳定发展，生态保护、社会和谐；建议将土地利用总体规划按国民经济发展需要安排三种周期： 战略规划——中长期土地规划；战役规划——五年土地规划和国家五年计划相协调；战术规划——区域土地详 细规划。区域土地规划具有目的统一性、决策整体性、总量不变性、需求动态性等特征；为了建立土地利用长 效机制，制止乱占耕地，建议全国人大设立枟土地利用规划法枠、枟基本农田保护法枠，用地球观测技术建立基本 农田台帐，动态定位格网监管，向农民发耕地承包使用证。
刘晅亚,陆守香,黄玥,陈国庆
《中国工程科学》 2006年 第8卷 第5期 页码 88-93
在不同障碍物挡板阻隔条件下，就细水雾对油池火的灭火效果进行了实验研究，分析了不同空间位置的障碍物挡板对细水雾灭火效果的影响，采用FDS40对细水雾与不同类型障碍物挡板油池火的相互作用过程的模拟结果表明：障碍物结构与类型影响着细水雾直接作用于油池火上方的水雾通量，油池火上方的水雾卷吸量越大，细水雾对障碍火的灭火效果越明显。
吴孝灵,周晶,王冀宁,彭以忱
《中国工程科学》 2014年 第16卷 第10期 页码 77-83
考虑到public private partnership（PPP）项目实际收益的不确定性，首先基于政府需求，通过引入项目运营收益的相对补偿指数，设计一种依赖特许收益的单期补偿契约；然后基于政府无法将私人投资变量纳入该契约，分别从集中决策与分散决策角度建立公私之间博弈模型来研究该契约的最优形式及其激励性与有效性，并给出政府有效补偿对策。研究表明：所得最优补偿契约既能激励私人选择政府集中决策时的最优初始投资，又能激励私人与政府共担风险、共享收益，但有效补偿还应满足项目社会效益约束，即对政府意味着有效补偿应适应项目实际不同情景。
王海桥,田峰,黄俊歆,陈涛
《中国工程科学》 2007年 第9卷 第11期 页码 43-47
根据独头巷道作业空间的特点，给出了独头巷道局部空气年龄、平均空气年龄的定义及其计算模型，用示踪气体测定平均空气年龄的方法和原理，并用CFD (computational fluid dynamics)对独头巷道附壁受限射流通风流场及平均空气年龄进行了数值计算，得出了独头巷道空间通风流场和平均空气年龄分布，建立了计算换气效率和排污效率的数学模型。研究表明影响通风有效性的主要因素是空气年龄和污染物浓度，而影响空气年龄主要是通风气流组织和通风量。为评价独头巷道通风有效性提供了一种新的理论依据。
Self-organizing method for collaboration in multi-robot system on basis of balance principle
DONG Yangbin, JIANG Jinping, HE Yan
《机械工程前沿（英文）》 2008年 第3卷 第3期 页码 283-287 doi: 10.1007/s11465-008-0044-z
关键词： algorithm self-organizing principle validity Simulation allocation
Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing
SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce
《机械工程前沿（英文）》 2006年 第1卷 第1期 页码 90-95 doi: 10.1007/s11465-005-0006-7
To exactly describe the contact state and contact area of tooth surface of toroidal involute (TI) worm gearing, the authors introduced boundary condition into contact line analysis.With helix angle chosen as parameter, the criterion for the existence of meshing boundary line on the surface of TI worm gearing is derived. Results show that there can be four situations for meshing boundary line on the tooth surface of gear, namely, inexistence of meshing boundary line, a unique line, two lines, and two coincident lines. If the helix angle is equal to or slightly smaller than the bigger angle, which makes two meshing boundary lines superpose, a preferable meshing performance is obtained. Computer simulation proves the validity of the above conclusion.
关键词： preferable inexistence Results validity boundary condition
房玉东,刘江虹,廖光煊,林霖
《中国工程科学》 2006年 第8卷 第2期 页码 75-79
传统水喷淋灭火系统很难扑救有障碍物遮挡的火焰。针对障碍物油池火进行了全尺寸细水雾灭火有效性的实验研究，深入了解障碍物存在时细水雾对油池火的抑制熄灭作用，同时研究了障碍物与火焰的相对位置、细水雾的工作压力、雾通量、喷头距火焰垂直距离及水平距离等关键因素对灭火有效性的影响，分析了障碍物存在时细水雾的灭火特性，揭示了实验中某些工况下不能扑灭火焰的原因，为细水雾的实际工程应用提供了科学的参考依据。
标题 作者 时间 类型 操作
IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing
null
期刊论文
Self-organizing method for collaboration in multi-robot system on basis of balance principle
DONG Yangbin, JIANG Jinping, HE Yan
期刊论文
Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing
SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce
期刊论文
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