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11.
在分析影响河北省高新技术产业发展主要因素的因果关系基础上,依据高新技术产业评价指标体系建立的原则,构建了高新技术产业的数学模型和评价指标体系,从产业投入、产业产出、产业技术创新能力、产业政策环境、科技人力资源的投入力度5个方面分析评价河北省高新技术产业的发展水平,旨在为加速发展河北省高新技术产业提供理论支撑。  相似文献   
12.
The purpose of this study was to analyse associations between lean soft tissue (LST), a surrogate of skeletal muscle mass and key fracture-related geometric characteristics of the proximal femur. Moreover, we examined the role that muscle played on the proximal femur geometry in response to physical activity (PA). Participants were 83 young adults. Leg LST (exposure) was assessed by dual energy X-ray absorptiometry (DXA). Proximal femur geometry was derived from a left hip DXA scan. Geometric variables (outcomes) included the femoral neck axis length (FNAL), the femoral neck width (FNW), the neck–shaft angle and FNW|FNAL (an index of robustness). PA was evaluated by accelerometry. Linear regression was used to analyse relationships. Additional exposure variables included body height and mass. In males, leg LST explained 17.4% of variation in FNAL (P < 0.001) and 15% in FNW (P = 0.015). In females, it explained 8.8% of the variance in FNAL (P = 0.020). Associations remained significant in males, but not in females, when vigorous PA was added to the models. These results suggest that public health approaches to promote PA may be particularly important in females since vigorous PA seems to convey advantages in femur geometry and consequently in bone strength.  相似文献   
13.
动态系统理论是应用语言学界的最新发展动态,它关注语言习得过程中各个内在系统的相互作用和系统内部各因素的相互联系。本文从该理论的基本概念出发,以二语词汇习得为研究点,结合动态系统理论的特点,讨论了该理论在二语词汇习得中的应用,并提出相关策略,以寻求词汇习得的新途径。  相似文献   
14.
As elite youth sport becomes more organized and professionalized, the role of the family is increasingly acknowledged as being significant in the development of young talent. High-profile examples across a range of professional sports, both positive and negative, have drawn attention toward this important stakeholder. Accordingly, this review first examines the key issues in relation to family involvement in talent development in relation to what is perceived as good and bad practice on behalf of the family. Next the key theoretical underpinning is considered, Family Systems Theory, and how it may be integrated within elite youth sport. Finally, the article concludes with a summary of where the current literature leaves us and where we can progress from here. Two possible inputs are suggested that could benefit the effectiveness of family involvement: a focus on the family holistically and a second on the role different family members can play.  相似文献   
15.
本文着重就四旋翼飞行器控制系统的硬件组成、结构和软件算法进行研究。介绍了四旋翼飞行器的组成结构和飞行原理,包括四旋翼飞行器的优势和特点以及今后的应用领域;讨论了控制系统的硬件组成结构及其特点,如主控制器MCU芯片的选择、所需传感器种类的确定、数据传输模块的设计和硬件通信协议的分析;研究了姿态解算的方法,包括捷联惯导系统、姿态解算的四元数方法、互补滤波;研究了四旋翼飞行器的控制方法,采用了经典的PID控制方法,设计偏航、俯仰、滚转的三路并行PID控制器。  相似文献   
16.
首先提出当前电子图书馆由于系统异构造成的兼容问题,然后就Z39.50、OAI-PM H和OpenURL等协议及标准对整合异构系统及所含资源的作用和效果进行详细分析,并就使用OAI-PM H协议进行系统整合的步骤和方法加以说明,最后对电子图书馆的联合检索应用前景进行总结和展望。  相似文献   
17.
设计模式使得人们可以更加简捷方便地复用成功的软件设计和体系结构,从而帮助设计者更快更好地完成系统设计。结合常州爱索物流管理系统的设计与开发,在物流管理系统中的订单处理模块应用了模板方法设计模式,解决了物流管理系统开发中代码重复、维护效率低的问题,加快了软件开发速度,降低了开发成本,提高了软件的可维护性,从而提升了经济效益。  相似文献   
18.
翟文 《中国科技纵横》2014,(2):175-176,178
介绍了梅花井煤矿1102206综采自动化工作面总体设计方案,对其各子系统进行了阐述。分析自动化工作面的采煤工艺,重点介绍了综采自动化工作面自动控制系统的总体设计,分析了自动控制系统的控制原理。建立了地面监控系统,实现对整个综采工作面集中监控。地面监控系统  相似文献   
19.
In this article, we present an experiential perspective on how a big data analytics course was designed and delivered to students at a major Midwestern university. In reference to the MSIS 2006 Model Curriculum, we designed this course as a level 2 course, with prerequisites in databases, computer programming, statistics, and data mining. Students in the class were mostly seniors or at the graduate level, and had a strong technical and quantitative background. We include details of concepts covered in the course, as well as summaries of four major sample course assignments used. Some of the concepts covered include large‐scale data collection and management using the Hadoop ecosystem, stream mining, visual analytics, and social network analytics. Besides Hadoop, the course also introduced various IBM and Teradata big data tools. We show how the course modules align with the intended learning goals and course objectives. A post‐course survey indicated that the structure and organization of the course helped students clearly and concisely assimilate the course content.  相似文献   
20.
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