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1.
企业试图完成数字化转型,这是在竞争中谋求发展的必经之路。文章率先进行数字化转型特征、策略的概念分析,而后总结以此为背景的能力模型、企业管理能力与技术能力,最终以某公司案例完成体系构建与应用的阐述。 相似文献
2.
《Ceramics International》2022,48(6):8325-8330
In this work, we propose a facile approach to fabricate Ti4+-doped Li3V2(PO4)3/C (abbreviated as C-LVTP) nanofibers using an electrospinning route followed by a high temperature treatment. In this designed nanocomposite, the ultrafine LVTP dots are homogeneously dispersed into one-dimensional carbon nanofibers and the Ti4+ doping does not destroy the crystal structure of monoclinic Li3V2(PO4)3. Compared to the undoped Li3V2(PO4)3/C (abbreviated as C-LVP), the as-fabricated C-LVTP fibers present higher reversible capacity, superior high-rate capability as well as better cyclic property. Especially, the C-LVT7%P cathode delivers not only high capacities of 187.2 and 160.3 mAh g?1 at 0.5 and 10 C respectively, but also stable cyclic property with the reversible capacity of 135.8 mAh g?1 at 20 C following 500-cycle spans. The good battery characteristics of C-LVT7%P can be mainly ascribed to Ti4+ doping, which can increase the electrical conductivity and Li+ diffusion coefficient. 相似文献
3.
《Ceramics International》2022,48(14):20237-20244
Composite anode materials with a unique architecture of carbon nanotubes (CNTs)-chained spinel lithium titanate (Li4Ti5O12, LTO) nanoparticles are prepared for lithium ion capacitors (LICs). The CNTs networks derived from commercial conductive slurry not only bring out a steric hindrance effect to restrict the growth of Li4Ti5O12 particles but greatly enhance the electronic conductivity of the CNTs/LTO composites, both have contributed to the excellent rate capability and cycle stability. The capacity retention at 30 C (1 C = 175 mA g?1) is as high as 89.7% of that at 0.2 C with a CNTs content of 11 wt%. Meanwhile, there is not any capacity degradation after 500 cycles at 5 C. The LIC assembled with activated carbon (AC) cathode and such a CNTs/LTO composite anode displays excellent energy storage properties, including a high energy density of 35 Wh kg?1 at 7434 W kg?1, and a high capacity retention of 87.8% after 2200 cycles at 1 A g?1. These electrochemical performances outperform the reported data achieved on other LTO anode-based LICs. Considering the facile and scalable preparation process proposed herein, the CNTs/LTO composites can be very potential anode materials for hybrid capacitors towards high power-energy outputs. 相似文献
4.
Stewart Clegg Catherine P. Killen Christopher Biesenthal Shankar Sankaran 《International Journal of Project Management》2018,36(5):762-772
Project portfolio management (PPM) bridges strategy and project management. Traditional research in PPM has primarily investigated the rational, top-down and structural aspects of strategizing. By doing so, it has failed to focus on the underlying practices that are triggered by the strategy and how these practices frame strategy implementation. Practice-based research provides a methodological lens to explore the reality of strategic enactment through the project portfolio. Practice-based perspectives are under-represented in PPM research; therefore the aim of this paper is to provide an agenda for further practice-based research in PPM. Central to this agenda is a concern with various aspects of practice, including its discursivity, representation, dynamic capabilities, leadership and materiality. 相似文献
5.
6.
Rice production encountered several challenges, especially among rural farmers in Northern Ghana. The current debate encompasses the belief of cultural norms and religious values as the right theory for the sustainability of agriculture. The belief in abstracts is prioritised to the adoption of improved rice. This paper examined the value attached to traditional rice varieties as a result of societal beliefs, and theoretically underpinned by the Dual-system hypothesis. The finding from three ethnic and religious groups through a survey indicates heterogeneity in the results but also demonstrates the factual importance of culture and religion. This paper, therefore, proposes a new way of categorising farming; as a business and a belief and that policy stream aim at small scale, rural farmers with belief peculiarities needs to adopt cultural and religious strategies to promote adoption. 相似文献
7.
根据组织项目管理成熟度模型(OPM3),确定影响项目组合管理能力的OPM3要素,分析OPM3要素与项目组合管理能力的因果关系,构建系统动力学模型,仿真模拟OPM3要素对项目组合管理能力的影响。仿真结果表明:OPM3要素与项目组合管理能力正相关;OPM3要素对项目组合管理能力的影响在短期内并不显著;在OPM3要素中,对项目组合管理能力影响较为显著的是战略执行与规划、组织领导能力和信息分析。 相似文献
8.
Micro ultrasonic machining (micro-USM) is an unconventional micromachining technology that has capability to fabricate high aspect ratio micro-holes, intricate shapes and features on various hard and brittle materials. The material removal in USM is based on brittle fracture of work materials. The mechanical properties and fracture behaviour are different for varied hard and brittle materials, which would make a big difference in the processing capability of micro-USM. To study the processing capability of USM and exploit its potential, the material removal of work materials, wear of abrasive particles and wear of machining tools in USM of three typical hard and brittle materials including float glass, alumina, and silicon carbide were investigated in this work. Both smoothed particle hydrodynamics (SPH) simulations and verification experiments were conducted. The material removal rate is found to decrease in the order of glass, alumina, and silicon carbide, which can be well explained by the simulation results that cracking of glass is faster and larger compared to the other materials. Correspondingly, the tool wear rate also dropped significantly thanks to the faster material removal, and a formation of concavity on the tool tip center due to intensive wear was prevented. The SPH model is proved useful for studying USM of different hard and brittle materials, and capable of predicting the machining performance. 相似文献
9.
为研究多时间尺度电力交易下配电网的最大供电能力,首先从中长期+现货交易模式入手,将多时间尺度下的交易转变为单时间尺度交易;其次,建立考虑多时间尺度电力交易市场下的配电网最大供电能力双层模型,并运用原始对偶内点法和改进的重复潮流算法求解;最后通过算例,对中长期+现货交易模式下的配电网最大供电能力进行计算分析。结果表明,考虑多尺度电力交易下的配电网最大供电能力得到了提升,且随着现货交易的深入,提升得越明显。研究成果可为电力市场环境下提升配电网最大供电能力提供参考。 相似文献
10.
Jiewu Leng 《国际生产研究杂志》2018,56(15):5131-5146
Evaluation on collaborative manufacturing network (CMN) structure characteristics has important implications for network operations such as production decision-making, product recovery, creating consensus. Several recent studies suggest that augmenting network structure with nodes’ attributes can provide a more fine-grained understanding of the network. However, there have been few studies to provide a systematic understanding of these effects in a CMN at scale. This gap is bridged using an industrial printing machinery CMN data-set collected on a web-based producing and outsourcing service platform. Novel phenomena with respect to both interaction and attribute metrics across and within the CMNs are observed. Moreover, although many studies employ either interaction or attribute data to study the relative roles of manufacturers in a CMN, relatively little is known about the relationship between these two types of data. This study explores this relationship by comparing two defined metrics (i.e. relational capability and node capability), which evaluate the manufacturers’ interactions and attributes, respectively. We examine to what extent the two metrics of manufacturers correlate with each other, and how possible dissimilarities and similarities can be explained based on the collected industrial CMN data-set. The insights thereby provide a better basis for efficient operations decision-making in CMN. 相似文献