Construction and operation of a microrobot based on magnetotactic bacteria in a microfluidic chip

Magnetotactic bacteria (MTB) are capable of swimming along magnetic field lines. This unique feature renders them suitable in the development of magnetic-guided, auto-propelled microrobots to serve in target molecule separation and detection, drug delivery, or target cell screening in a microfluidic chip. The biotechnology to couple these bacteria with functional loads to form microrobots is the critical point in its application. Although an immunoreaction approach to attach functional loads to intact MTB was suggested, details on its realization were hardly mentioned. In the current paper, MTB-microrobots were constructed by attaching 2 μm diameter microbeads to marine magnetotactic ovoid MO-1 cells through immunoreactions. These microrobots were controlled using a special control and tracking system. Experimental results prove that the attachment efficiency can be improved to ∼30% via an immunoreaction. The motility of the bacteria attached with different number of loads was also assessed. The results show that MTB can transport one load at a velocity of ∼21 μm/s and still move and survive for over 30 min. The control and tracking system is fully capable of directing and monitoring the movement of the MTB-microrobots. The rotating magnetic fields can stop the microrobots by trapping them as they swim within a circular field with a controllable size. The system has potential use in chemical analyses and medical diagnoses using biochips as well as in nano/microscale transport.     

服务供应链中内部企业知识的关联性研究

对服务供应链的运作特点进行研究,在明确服务供应链的内部企业知识构成的基础上,运用结构方程模型揭示服务供应链内部企业知识的相互作用关系。     

都市圈创新能力发展不均衡程度的测度方法研究

借鉴创新能力和区域经济发展不均衡的相关研究,在构建都市圈创新能力指标体系的基础上重构了基尼系数模型.以专利数据与创新能力综合数据两种方式,基于上海都市圈2001-2010年的面板数据,对比分析上海都市圈创新能力的不均衡发展情况,为上海都市圈创新能力的协调发展和制定相关政策提供依据.     

技术管理能力对新产品开发绩效的影响路径识别——基于动态能力视角

从技术管理能力的动态结构入手,分析了技术管理能力、知识吸收能力和新产品开发绩效的作用关系,并利用102家企业的调查数据对其进行检验。研究结果表明:技术管理能力能够直接对新产品开发绩效产生显著的正向影响,也能够通过知识吸收能力对新产品开发绩效产生间接的显著正向影响;技术管理能力的间接作用与直接作用同等重要;在不同作用路径上,技术管理能力要素的作用会产生差异。在此基础上识别了技术管理能力影响新产品开发绩效的主导路径,并构建了作用路径模型。     

新生代农民工市民化的障碍及路径探析

促进新生代农民工市民化是解决农民工问题的主要出路,是统筹城乡发展、全面建设小康社会、加速我国城镇化进程的关键环节,是建设社会主义和谐社会的内在要求,直接影响到我国社会转型与变迁.当前,推进新生代农民工群体市民化进程进展的并不顺利,面临诸多障碍.深入分析、论证、优化新生代农民工群体市民化的路径选择则成为一项关系建设全局的紧迫工作.     

Adaptive sliding mode tracking control for a flexible air-breathing hypersonic vehicle

This paper is concerned with the adaptive sliding mode control (ASMC) design problem for a flexible air-breathing hypersonic vehicle (FAHV). This problem is challenging because of the inherent couplings between the propulsion system, the airframe dynamics and the presence of strong flexibility effects. Due to the enormous complexity of the vehicle dynamics, only the longitudinal model is adopted for control design in the present paper. A linearized model is established around a trim point for a nonlinear, dynamically coupled simulation model of the FAHV, then a reference model is designed and a tracking error model is proposed with the aim of the ASMC problem. There exist the parameter uncertainties and external disturbance in the model, which are not necessary to satisfy the so-called matched condition. A robust sliding surface is designed, and then an adaptive sliding mode controller is designed based on the tracking error model. The proposed controller can drive the error dynamics onto the predefined sliding surface in a finite time, and guarantees the property of asymptotical stability without the information of upper bound of uncertainties as well as perturbations. Finally, simulations are given to show the effectiveness of the proposed control methods.     

高校科研经费投入与城市经济增长关系的实证分析——以京津沪为例

通过对京津沪三地中高校创新投入对城市经济的影响进行分析,结果表明,政府对高校科研经费的投入对北京的经济的影响较大,而企业对高校科研经费的投入对天津和上海城市经济的影响较大.为提高高校科研活动对城市经济的拉动作用,必须引导高校与企业之间的合作.     

信息与计算科学专业的信号处理课程改革

信号与系统和数字信号处理是很多工科专业的核心课程．直接将其教学方案应用于信息与计算科学专业将会带来很多不便。本文基于华北水利水电学院的专业课程改革,通过对专业培养方案中的授课内容探讨以及市场上的教材分析,结合专业自身特点,建立了一套适用于本专业的信号处理课程理论培养体系。该体系在减少学时的基础上．能够顺利完成所有知识点的教学,符合专业培养要求。     

篆刻艺术在美术教学中的探索与创新实践

篆刻艺术源远流长,在历史的长河中去伪存精,形成了阴文粗壮,阳文劲挺的线条特色及疏密有致,刚柔相济的章法特色,是一门与书法密切结合的传统艺术。由于其使用材料的特殊性与技法的专业性及篆刻教学难度较大等原因,一些学生的学习积极性也受到影响。笔者通过反复的教学实践,探索出了以结合现代设计手法及形式的橡皮章印刻代替传统的篆刻教学,使篆刻这一传统的艺术焕发出年轻的生命力,取得了较好的效果。     

依托素质型人才理念的高校思想政治教育改革

当前,在我国现代高等教育体系中,正确的教学理念往往是教学活动成功的基础。具体到高校思想政治教育而言,能否建立和依托素质型人才理念是日常教学活动能否取得改革成功的关键。本文拟从素质型人才培养理念出发,进一步思考和探讨高校思想政治教育的优化和改革,以期为我国当前高等院校思想政治教育的良好发展探索出一条可行的有效路径。