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51.
为适应经济社会和技术环境的快速变化,依据竞优理论,从客体特质模式识别的角度对RD人员的绩效进行分析和评价。首先,基于对RD人员不同绩效价值的认同,从体现RD人员个体优势的角度对其特质进行识别;其次,通过聚类分析的方法对RD人员的个性特质进行共性提炼,得到RD人员特质的不同模式;然后,从兼顾RD人员数量和信息一致性的角度,计算各模式的权重值,从而获得各RD人员的绩效评价值;最后以15名RD人员为例,对所提方法的可行性和有效性进行验证。  相似文献   
52.
The goal of this study is to measure the effectiveness of a career development system implemented at a research and technology organization at satisfying the context requirements of a decree issued by the Basque Country government. Through in-depth surveying of 80 R&D professionals over the five years, the authors aimed to determine whether a career development system, when it is linked to context requirements and researchers’ contributions, could offer researchers feedback about their career aims and increase their job satisfaction. During the five years of the study, the researchers’ capacity to meet career requirements improved by 20%, and job satisfaction, although it declined at first, increased substantially in the last two years, reaching a historic high for the employee satisfaction survey.  相似文献   
53.
The manufacture of 3D mesostructures is receiving rapidly increasing attention, because of the fundamental significance and practical applications across wide-ranging areas. The recently developed approach of buckling-guided assembly allows deterministic formation of complex 3D mesostructures in a broad set of functional materials, with feature sizes spanning nanoscale to centimeter-scale. Previous studies mostly exploited mechanically controlled assembly platforms using elastomer substrates, which limits the capabilities to achieve on-demand local assembly, and to reshape assembled mesostructures into distinct 3D configurations. This work introduces a set of design concepts and assembly strategies to utilize dielectric elastomer actuators as powerful platforms for the electro-mechanically controlled 3D assembly. Capabilities of sequential, local loading with desired strain distributions allow access to precisely tailored 3D mesostructures that can be reshaped into distinct geometries, as demonstrated by experimental and theoretical studies of ∼30 examples. A reconfigurable inductive–capacitive radio-frequency circuit consisting of morphable 3D capacitors serves as an application example.  相似文献   
54.
文章通过对勃拉姆斯《D大调小提琴协奏曲》的详细剖析,从主题构建、呈示部创作、全曲整合多角度分析阐述展开式变奏在特定作品中的实际运用,并探析在这首作品中展开式变奏所呈现的独特创作技法,为研究勃拉姆斯创作手法中的创新性提供一定的参考。  相似文献   
55.
以我国316家信息技术业上市公司2014—2018年面板数据作为研究对象,通过运用多元线性回归和调节效应检验研究研发投入与经营绩效的关系及股权结构在二者关系间的调节作用。研究结果表明:第一,研发投入与企业经营绩效正相关,且研发人员投入对企业经营绩效的影响高于研发资金投入;第二,股权集中度、股权制衡度均与企业经营绩效正相关。因此,信息技术企业在提高研发创新能力时不仅需要足够的资金保障,更需要充足的智力支持,且适度提高股权集中度、股权制衡度可在一定程度上提高企业经营绩效。  相似文献   
56.
为解决航空发动机空心涡轮叶片陶瓷型芯的3D打印难题,研究基于图像投影的复杂结构陶瓷型芯光固化成型(mask-image projection stereolithography,MIP-SLA)方法。搭建MIP-SLA工艺系统平台,对陶瓷浆料的制备和打印工艺参数的配置进行研究。分析利用球磨机将光敏树脂和陶瓷颗粒进行混合制备陶瓷浆料时,光敏树脂类型、固相含量、陶瓷颗粒粒径、分散剂含量和球磨时间对陶瓷浆料性能的影响。对不同配置参数下的打印效果进行对比分析,对确定的最佳打印工艺参数进行打印效果验证。  相似文献   
57.
通过实例说明了简化D值法对框架结构进行的侧移估算,为结构的初步设计提供方便.  相似文献   
58.
Negative work, which is mainly generated by eccentric muscle contraction, has an important influence on the associated muscle damage. Generally, mechanical parameters are determined for one side of a lower extremity on the assumption of negligible between-limb differences. However, between-limb differences in the negative work of lower extremity joints during running remain unclear. This study examines between-limb differences in negative work and associated mechanical parameters during the contact phase of running. Twenty-five young adult males voluntarily participated in this study. Each participant was asked to run on a straight runway at a speed of 3.0?m?s?1. Negative work, amplitude, duration of negative power, moment, and angular velocity were computed for both sides of the lower extremities. Significant differences were found in negative work between limbs for the hip (18.9?±?11.7%), knee (13.6?±?10.4%), and ankle (11.8?±?8.5%) joints. For the hip joint, asymmetric negative work was attributable to the between-limb difference in the amplitude of negative power owing to a corresponding difference in the moment. The between-limb differences concerning the duration and amplitude of negative power could explain the asymmetric negative work in the knee joint. The asymmetric negative work of the ankle joint was attributable to the between-limb difference in the amplitude and duration of the negative power and the moment. These results indicate that asymmetric negative work was generated in each lower extremity joint; however, the major mechanical parameters corresponding to the negative work are not the same across the joints.  相似文献   
59.
在重轨干涉实际测量中,两次飞行航迹难以保持高度重合,飞行高度和姿态不稳定,干涉图像对存在明显不规则的相对形变,难以进行三维定位。通过分析重轨机载InSAR图像对的几何形变和形成原因,提出一种从精准的InSAR成像几何关系出发,通过修正成像参数,实现机载重轨InSAR高精度三维定位的方法。该方法通过引入地面控制点,实现干涉图像对精准的相对定位,生成高精度DEM;并利用高精度DEM,实现机载重轨InSAR高精度三维定位。对比检查点实测结果和定位结果,表明该方法可有效地解决机载重轨InSAR的三维定位困难的问题。  相似文献   
60.
Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cell–cell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering.  相似文献   
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