Application of 2-D Position Sensitive Detector in Spatial Straightness Measurement of Guide Rails

A laser collimating system based on 2-D position sensitive detector (PSD) is presented in this paper. The working principle of PSD is depicted in detail. A calibration device was developed to check the nonlinearity errors of PSD and a multilayer feedforward neural network based on error back-propagation algorithm was used to compensate errors. With the aid of computer-based data acquisition system, an automatic dynamic measuring process was realized. A series of experiments, including comparison tests with laser interferometer, were done to evaluate the performance of the measuring system. The experimental results show that the spatial straightness errors of guide rails can be measured with high accuracy. The maximum differences between the device and laser interferometer are 0. 027 mm in Y direction, and 0. 053 mm in X direction in the measuring distance of 6 m.     

英国企业开展员工培训的现状分析

员工培训是职业培训的有机组成部分,通过分析英国企业开展员工培训的现状,揭示企业规模与培训开展情况及培训内容的关系,各类外部培训机构的优缺点,以及英国政府和国家职业教育体系在企业员工培训中的地位和作用。     

开放式虚拟经济实验室设计及其技术手段研究

虚拟经济实验室在经济预测、决策支持以及理论教学等方面所体现出的强大功跑,使其成为当今国内外研究的热点。该文在对具体案例进行了分析与研究的基础之上,提出了该校“开放式虚拟经济实验室”项目的总体设计;并通过对实验范例的分析与实践,给出了三种在线实验方式的实现方法及技术手段。     

中国影视文化中帝王题材剧盛行现状之我见

文章对古装帝王剧盛行的现状进行了思考,认为帝王剧一味地赞美帝王权术,不去挖掘封建君主制度没落的根源,不利于法制社会的建设.作者认为影视文学创作应正视当今社会矛盾问题,在实现其娱乐性的同时,要充分体现它的教育性和具有励志作用.     

实施高职学生创业教育的实践与探索

本文认为，加强创业教育是实现高职教育培养目标的重要措施。充分发挥课堂教学、第二课堂、社会实践这“三大板块”教学渠道的作用，构建高职学生创业教育模式，是实施高职学生创业教育的有效途径。     

Gene transfer into primary cultures of fetal neural stem cells by a recombinant adenovirus carrying the gene for green fluorescent protein

Objective: To evaluate the transduction efficiency of a recombinant adenovirus carrying the gene for green fluorescent protein (Ad-GFP) into the primary cultures of fetal neural stem cells (NSCs) by the expression of GFP. Methods: The Ad-GFP was constructed by homologous recombination in bacteria with the AdEasy system; NSCs were isolated from rat fetal hippocampus and cultured as neurosphere suspensions. After infection with the recombinant Ad-GFP, NSCs were examined with a fluorescent microscopy and a flow cytometry for their expression of GFP. Results: After the viral infection, flow cytometry analysis revealed that the percentage of GFP-positive cells was as high as 97.05%. The infected NSCs sustained the GFP expression for above 4 weeks. After differentiated into astrocytes or neurons, they continued to express GFP efficiently. Conclusion: We have successfully constructed a viral vector Ad-GFP that can efficiently infect the primary NSCs. The reporter gene was showed fully and sustained expression in the infected cells as well as their differentiated progenies.     

学以致用 以用促学

读写脱节一直是中学语文教学存在的不良现象 ,也是语文教学低效的重要原因。如何使学能致用 ,以用促学 ?本文提出了读写结合的教学模式 ,并从三个环节对这一模式进行探讨。     

人的主体地位的首次确立--普罗泰戈拉的名言"人是万物的尺度"阐释

文章对普罗泰戈拉的名言"人是万物的尺度"作出阐释,认为,其中"人"是指作为主体的人,"万物"是指作为客体的存在物;"人"作为"万物"的尺度不仅指本体尺度,同时还是认识尺度、价值尺度和审美尺度;它标志着人的主体地位的首次确立.     

滁州市中小学教师心理健康状况调查

中小学教师心理健康状况事关学生心理健康发展和教育事业的发展。通过对滁州市中小学教师心理健康状况的调查,有利于采取措施,促进中小学教师心理健康发展。     

高校药物合成实验室常见危险因素分析

就药物合成实验室潜在的危险因素进行了探讨与研究,结合实际案例介绍了实验室常用危险试剂、常见实验操作存在的安全隐患,并提出安全操作的合理建议.