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11.
It is a wide-held assumption that professional development and change within purchasing and supply management (PSM) organisations can be explained and guided by a maturity model. In this paper the guidance which the maturity model concept offers to understand a PSM organisation's performance is assessed. The methodology is based on the outcomes of a literature review of PSM maturity models, development of an organisational change framework and the learning from three qualitative case studies. An alternative understanding of the development of the PSM organisation is offered through an organisational change framework, composing 1) movement transitions, 2) scalability of change, 3) acceptability of change, and 4) the substantive element of change. The research found that extant PSM maturity models are too rigid for PSM managers to apply, and although maturity models are commonly accepted in PSM literature, in practice, they may produce the opposite effect of what is promised. The PSM maturity models suggest that their application will lead to increased status and influence of PSM within the organisation; expectations that may not be met. PSM organisations’ change processes are subjected to a range of situational and contextual power relations which must be considered in order to advance the specific PSM organisation roles and responsibilities.  相似文献   
12.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
13.
This paper uses data at the trading day frequency and the method of local projections to quantify the dynamic responses of U.S. airline stock prices to a COVID-19 shock. We show that airline stock prices decline immediately by 0.1 percentage point in response to a 1% COVID-19 shock. In addition, the effect of the shock persists beyond the day on which it occurs, with most airline stock prices falling by as much as 0.6 percentage points after fifteen days. This negative response of airline stock prices to a COVID-19 shock is not explained by a COVID-19-induced increase in airlines’ variable costs, but rather by a COVID-19-induced decrease in air travel, which, in turn decreases revenues, profitability, and stock prices of U.S. airlines.  相似文献   
14.
This paper examines the phenomenon of the “Solow paradox” in China using the Annual Survey of Industrial Production database and the China Customs Records dataset from 1998 to 2007. We find that China likely fell into the Solow paradox in the period 1998–2002, but the total factor productivity of information and communication technology (ICT) enterprises has achieved rapid growth since 2003. Accession to the World Trade Organization is the key reason for China to overcome the Solow paradox, that is, input tariff reduction significantly promoted the productivity of ICT firms. A series of validity and robustness checks confirmed the results. Mechanism analysis shows that input liberalization promotes the productivity of ICT firms through optimizing factor structure, importing more and high-quality inputs, and increasing research and development investment. The conclusions provide strong empirical evidence for developing countries to overcome the Solow paradox through trade liberalization.  相似文献   
15.
我国自然垄断产业的民营化改革   总被引:1,自引:0,他引:1  
在自然垄断产业,国有企业垄断经营低效是一个世界性的问题。自然垄断产业在一定范围内具有可竞争性,即使是在不可竞争性的领域,也可以通过建立潜在的竞争性替代机制,形成模拟竞争环境。自然垄断产业的可竞争性为民营化提供了可能。自然垄断产业民营化就是通过产权制度变革,提高垄断企业的效率。  相似文献   
16.
B.   《Technovation》2003,23(12):929-937
This research investigates the degree of emphasis placed by the Australian manufacturing industry on Research and Development (R&D) strategy as well as on other organisational strategies such as marketing, HRs (HR), technology, and operations at the functional level. The research extends further to investigate whether the emphasis on R&D strategy differs with contextual factors such as firm size, firm’s generic strategy, type of market, firm’s life cycle stage, etc. A mail survey was carried out to collect information from manufacturing firms across Australia. This was followed by an on-site interview of some of the senior managers of manufacturing firms from three Australian states: South Australia, Victoria and New South Wales.The study found that although the emphasis on R&D strategy has received a high priority in the past few years, it has not been as effective as the operations strategy and the technology strategy. The operations strategy has been accorded the highest importance in the past few years and this will continue in the future. The study also indicated that firms, which adopt a differentiation generic strategy, put more emphasis on R&D than the firms, which adopt cost leadership and focus generic strategies. The results did not indicate any evidence of a relationship between firm size and the R&D strategy although large firms are found to put more emphasis on operations and marketing strategies. Relatively higher emphasis was placed on the R&D strategy by businesses: at the growth stage; involved in the manufacture of consumer goods as opposed to industrial goods; involved in exports with a higher sales growth in export markets; and having a higher growth rate relative to their industry.  相似文献   
17.
董事会中心主义的确立,董事义务与责任体系的完备,使得对董事利益的保护成为公司经营管理效率提高的必要前提。如何建立符合中国实际的董事利益保护机制是摆在法学研究者面前一个紧迫而重要的课题。  相似文献   
18.
工业设计人才培养体系的构建和优化   总被引:2,自引:0,他引:2  
该文从现代企业的生产方式及工业设计师应具备的基本素质出发,阐述了21世纪工业设计专业人才的培养体系和培养模式及其特点,构建了培养工业设计应用型人才的课程体系。  相似文献   
19.
实施北部湾战略的着力点应放在提高产业竞争力方面。文章就此提出了八大关于选择、布局、培育、发展具有强大竞争力产业的方式方法和途径。  相似文献   
20.
严姝娜  焦洁 《物流技术》2005,(9):199-202
以某跨国零售连锁企业登陆武汉为背景,通过实地考查并搜集资料,采用模型计算和定性分析的方法,从理论研究角度对该公司进行了在武汉地区的模拟选址,最后与实际结果进行了对比。  相似文献   
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