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关于培养大学生就业与创业能力的思考 总被引:1,自引:0,他引:1
王培华 《西安航空技术高等专科学校学报》2003,21(4):54-56
在高校毕业生就业问题日趋严峻的形势下 ,本文阐述了教育与培养学生就业与创业之间的关系和重要意义 ,分析了我国高等教育的发展与毕业生就业之间的矛盾 ,提出了培养学生就业与创业能力的具体措施 ,使学生在校期间就能迎接未来的生存挑战 ,积极参与社会变革 ,理性选择就业模式 ,主动开创事业成就 ,进而创造自己美好人生 相似文献
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T D Yang J S Pei S L Yang Z Q Liu R L Sun 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,30(4):751-755
Space motion sickness (MS) is one of the most important problems in the field of space medicine. In order to prevent space MS, a new medicine, PMPA, has been prepared by means of synthesizing in our laboratory. The purposes of this study were to set up animal models of PMPA against MS, and to observe its effects on anti-MS, and to prove its function of antagonism to choline. Eight cats, forty rabbits and two hundred and ten rats were selected as animal subjects. The parallel swing stimulus, a method causing the reversal syndromes and tests of anti-choline function were used in our experiments. The results are as follows: (1) The score of MS symptoms in cats with PMPA or scopolamine (SCOP) is significantly lower than that in cats with placebo (p<0.01), while the incidences of efficiency and prevention of PMPA (87.5%, 75%) are higher than those of SCOP (75.0%, 50%) in cats. (2) PMPA of 1.6 mg/kg or 0.8 mg/kg could antagonize the reversal syndromes and repress reversal rotation significantly in rabbits like SCOP in comparison with placebo (p<0.01). (3) PMPA could inhibit tremor evoked by oxotremorine or by nicotine-procaine in rats like SCOP, and play an important role in the antagonism to central M-choline and N-choline receptors. The animal experiments demonstrate that PMPA is an effective medicine against MS with antagonism function to choline. 相似文献
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Autonomous orbit determination via integration of epoch-differenced gravity gradients and starlight refraction is proposed in this paper for low-Earth-orbiting satellites operating in GPS-denied environments.Starlight refraction compensates for the significant along-track position error that occurs from only using gravity gradients and benefits from integration in terms of improved accuracy in radial and cross-track position estimates.The between-epoch differencing of gravity gradients is employed to eliminate slowly varying measurement biases and noise near the orbit revolution frequency.The refraction angle measurements are directly used and its Jacobian matrix derived from an implicit observation equation.An information fusion filter based on a sequential extended Kalman filter is developed for the orbit determination.Truth-model simulations are used to test the performance of the algorithm,and the effects of differencing intervals and orbital heights are analyzed.A semi-simulation study using actual gravity gradient data from the Gravity field and steady-state Ocean Circulation Explorer (GOCE) combined with simulated starlight refraction measurements is further conducted,and a three-dimensional position accuracy of better than 100 m is achieved. 相似文献
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对固体火箭发动机探伤图像中出现的包络线伪迹进行了相应的研究,介绍了滤波反投影算法,分析了探伤图像中包络线伪迹产生原因,提出了相应的解决方法。对相应方法首先进行了计算机仿真验证,然后进行了固体发动机探伤图像包络线伪迹校正实验研究,取得了理想的效果。 相似文献
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针对叶片加工过程中质量精度不高的问题,提出了基于动态Bayesian网络的叶片加工质量监控与溯源方法.利用动态Bayesian网络建立起叶片加工工序间的相互联系,实现对整个加工过程的控制.基于Bayesian网络对影响加工工序的因素集建立因果联系,采用多元统计过程控制中的T2控制图完成对各工序影响因素集的监控.进行误差溯源时,根据Bayesian网络建立的因果关系对失控样本的T2统计量依据原因变量进行误差分解,并构建各分解变量的控制限,将其作为误差源判定的条件.通过对某叶片加工过程的仿真,验证了所提方法的有效性. 相似文献