Physiological responses of elite Laser sailors to 30 minutes of simulated upwind sailing

In this study, we tested the hypothesis that elite dinghy sailing is a whole-body, dynamic, repeated-effort sport, and that increased heart rate and oxygen consumption reflect its dynamic element. Six elite male Laser sailors (mean age 19.7 years, s = 1.82; height 1.81 m, s = 0.03; body mass 78.0 kg, s = 4.1) performed a cycle ergometer test to volitional exhaustion to determine peak oxygen uptake (VO(2peak)) and a simulated 30-min upwind leg sail on a specially constructed Laser sailing ergometer. The simulation protocol was based on video analysis of previous Laser World Championships. Expired gases were collected in Douglas bags, heart rate recorded at rest and after every 5 min, and pre- and post-simulation capillary blood samples taken for blood lactate analysis. Results were analysed with a one-way analysis of variance. Mean VO(2peak) was 4.32 l . min(-1) (s = 0.16). Mean simulation VO(2) was 2.51 l . min(-1) (s = 0.24) and peaked at 2.58 l . min(-1) (s = 0.25) during the 5th minute. Mean simulation heart rate was 156 beats . min(-1) (s = 8), peaking during the final minute at 160 beats . min(-1) (s = 10). These results suggest that, unlike pseudo-isometric static hiking, elite dinghy sailing demands a substantial proportion (58%VO(2peak), s = 5.6) of aerobic capacity.     

温州霓屿料场露天矿边坡稳定性分析

以温州市专供料场露天矿高边坡为工程依托,对边坡局部水平位移和竖向位移进行实时监测分析,并利用岩土分析软件FLAC 3D对实时监测区域进行数值模拟分析,从监测和数值模拟2个方面来判断边坡的稳定性.根据监测和模拟分析结果可知:边坡在监测初期位移值变化较大,之后变化值便趋于平缓,最终累计位移值在安全警戒值内,边坡整体处于稳定的状态,但不排除局部出现滑坡的可能性;边坡的坡脚处容易出现挤压破坏,坡面可能发生现拉应力导致的地表裂缝,应对边坡的坡脚和表面进行安全支护;高边坡的累计位移值与坡高成一定的正比关系,随着高度的增高,位移值也逐渐增大.