Revisit the K-segment of the Southeast Indian Ridge for new evidence of hydrothermal plumes

During the first leg of a Chinese research cruise to the Southeast Indian Ridge (SEIR) in 2007, we revisited the K-segment of the SEIR and observed a water column turbidity anomaly at a CTD cast station. This station was located ~400 m from a dredge site on a plume anomaly detected in 1996 by US scientists. The characteristics of the turbidity anomaly detected in our survey are different from those observed 11 years previously, implying that either the detected anomalies have distinct and different plume sources or the robustness of the plume has changed in the intervening time. In addition, turbidity anomalies were observed at two localities on the K-segment in a deep tow-yo profile. If these two anomalies are not connected, the plume incidence calculated would be about 0.28, larger than the predicted value of 0.25 for a 65 mm/a spreading rate. This increase in plume incidence on the K-segment seems to be related to the influence of the St. Paul-Amsterdam hotspot, located about 300 km to the northwest.     

增塑剂行业的现状和发展

介绍了我国增塑剂行业的现状及发展趋势,指出了行业当前面临的主要问题和发展瓶颈,提出了相应的应对措施。     

一种基于POMDP用户意图建模的智能轮椅导航控制方法

通过部分可观测马尔可夫决策过程(POMDP)模型对用户意图进行建模,提出了一种基于POMDP用户意图建模的智能轮椅导航控制方法.该方法考虑了动作的不确定性和状态的部分可观测性,对用户意图、智能轮椅导航控制的动作空间进行建模,通过状态预测进而选择行为的最优规划,实现用户期望总值的最大化.首先介绍了POMDP的原理及模型,然后提出了基于POMDP用户意图的智能轮椅控制状态空间、动作空间、观察值集合、奖赏值和概率分布,进而提出了一种基于概率密度函数的用户意图求解方法.最后,对基于POMDP用户意图建模的智能轮椅导航控制进行了试验,并对试验结果进行了分析,从而验证了所提方法的实时性和有效性.     

非本征光纤F—P传感器制作工艺

分析非本征光纤F-P传感器制作工艺上存在的问题,对传感器工艺制作进行了研究,设计了半自动光纤F-P腔调节工作台,利用光纤五维调节架对光纤进行插入和对准,提高了光纤F-P传感器制作的速度和质量。     

粘土耐火度公式的理论根源探究

对粘土耐火度公式的理论根源和存在的问题进行了探讨，认为Ｋ２Ｏ－Ａｌ２Ｏ３－ＳｉＯ２三元相是推导此粘土耐火度公式的理论依据。虽然用它来计算粘土耐火度既简单又方便，但是由于粘土中各种氧化物杂质对其耐火度影响程度的不同，导致其计算结果与真实值之间存在一定的误差，往往呈偏高趋势。     

双梁桥式起重机的主梁截面尺寸优化

本文以起重机设计规范为依据，对《起重机设计手册》中推荐的主梁截面进行了验算，给出了各计算指标值，并推荐了新的主梁截面尺寸，供设计时参考选用     

Contents and distribution of rare earth elements in wheat seeds

Contents of 15 rare earth elements (REEs) in the seeds of 60 breeds of wheat have been analyzed by the inductively-coupled plasma mass spectrometry (ICP-MS). The distribution pattern of contents of REEs in wheat seeds has been observed and compared with that in soils. Comparison with literature data has also been made. The results show that the background of REEs in wheat seeds is 10-11-10-8 g.g-1, 3-4 levels lower than in soils. The distribution pattern is light REEs higher in contents and slight Eu-anomaly, similar to that in soils. The data obtained in this study can accurately represent the background content of REEs in wheat seeds.     

逐步完善学分制全面推进素质教育

素质教育是我国高等教育改革的主题,学分制是实施素质教育的有效途径,也是深化教育教学改革的重要组成部分.逐步实施学分制是全面推进素质教育的可靠保障.素质教育的根本任务就是培养学生的主体意识、创新精神和实践能力.在具体实施素质教育的过程中,必须进一步完善学分制管理模式,推动教育教学改革.     

QoS over Internet

The integrated services and differentiated services architectures that can be used to support Quality of Service (QoS) guarantees over Internet are analysed. Specifically, how they can interwork in the pursuit of end-to-end QoS is discussed.